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THE SIG

AMERICAN GEOLOGIST

A MONTHLY JOURNAL OF GEOLOGY
. AND

ALLIED SCIENCES

Editor: N. H. WINCHELL, Minneapolis, Minn.

ASSOCIATE EDITORS:

FLORENCE BAscom, Bryn Mawr, Pa.

CHARLES E. BEECHER, New Haven, Conn.

SAMUEL CALVIN, Iowa City, Iowa.
JOHN M. CLARKE, Albany, N. Y. PERSIFOR FRAZER, Philadelphia, Pa.
EDWARD W. CLAYPOLE, Pasadena, Cal. Utysses S. GRANT, Evanston, Il.
HERMAN L. FAIRCHILD, Rochester,N.Y. GEORGE P. MERRILL, Washington, D.C.

WARREN UPHAM, St. Paul, Minn.

ISABEL C. WHITE, Morgantown, W. Va.

VOLUME XXVII

JANUARY TO JUNE, 1901

MINNEAPOLIS, MINN.
H. W. Witson
1901

THE UNIVERSITY PRESS OF MINNESOTA .

Digitized by the Internet Archive
in 2010 with funding from |
University of Illinois Urbana-Champaign

http://www.archive.org/details/panamericangeolo271901desm

he ede

GONPENTS:

JANUARY NUMBER.
Brevity oF Turr-Cone Eruption. S. E. Bishop. [Plate I]......

PossistE New Coa PLANTS, Bac etnmCour, wtbart Lil; [Plates
IEW IDC SHR Sed C7 (I OA ee Ae a

‘On THE PETROGRAPHY oF Mount Orrorp. John A. Dresser.......

On Some Newry Discoverep AREAS OF NEPHELINE SYENYTE IN
ATMA GANT AIA SV TILED Gr. VIGIL Eats slat ets ace ny spavecnla eo dpelese.eve bee's

PENEPLAINS OF THE OZARK HIGHLAND. Oscar H. Hershey........

CoRRESPONDENCE.
Troost’s Survey of Philadelphia, S. Harbert Hamilton, 41;
New York Academy of Sciences, Section of Geology and Min-
eralogy, Theo. G. Wiute, 42; A Single Occurrence of Glacia-
tion in Siberia, C. WV. Purington, 45.

REVIEW OF RECENT GEOLOGICAL LITERATURE.
Ueber Aulacamerella ein neues Brachiopodengeschecht, Fried-
rich Baron Hoyningen-Huene, 47; Supplement zu der Beschrei-
bung der Silurischen Craniaden der Ostseelander, Same Au-
thor, 47; A text-book of important minerals and rocks, S. E.
Tillman, 48; Progress of Mineralogy in 1899, S. Harbert Ham-
ilton and James R. Withrow, 48; New Species of Cambrian
Fossils from Cape Breton, G. F. Matthew, 49; The Action of
Ammonium Chloride upon Natrolite, Scolecite, Prehnite and
Pectolite, F. WV. Clark and George Steiger, 49; Chemical Com-
position of Turquois, S. L. Penfield, 50; A new meteorite from
Oakley, Logan County, Kansas, Hf. L.. Preston, 50; Cambro-
Silurian Limonite Ores of Pennsylvania, 7. C. Hopkins, 50;
Chemical Composition of Sulphohalite, S. L. Penfield, 50;
Siliceous Calcites from the Bad Lands of South Dakota, S. L.
Penfield and JV. E. Ford, 51; Granites of Southern Rhode Isl-
and and Connecticut, J. /. Kemp, 51; Contact Metamorphism
of a basic Igneous Rock, UL’. S. Grant, 51; Suggestions Regard-
ing the Classification of the Igneous Rocks, IV’. H. Hobbs, 52;
The Nomenclature of Feldspathic Granolites, H. W. Turner,
53; Some Contact of Phenomena of the Palisade Diabase, J.
D. Irving, 53; Ueber grosse flache Ueberschiebungen in Dill-
gebiet, E. Kayser, 54; Ueber den nassauischen Culm, E. Kay-

SS site ae Ramen a>

6
™4

bo
Un

IV Contents.

ser, 54; Beitrage zur Kenntniss des Siberischen Cambrium, J.
E. von Toll, 54; La Face de la Terre (Das Antlitz der Erde),
E. Suess, 56; A record of the Geology of Texas for the Decade
ending December 31, 1896, F. Ji’. Simonds, 56; Bulletin of the
Hadley Laboratory of the University of New Mexico, C. L.
Herrick and others, 58; The Geology of Eastern Berkshire
county, Mass., B. K. Emerson, 59.

MontTHity AvutHors’ CATALOGUE OF AMERICAN GEOLOGICAL LITERA-
TWO fk ER

PERSONAL AND SCIENTIFIC NEWS..«'..< ...+-55> isle e va » sere eee
FEBRUARY NUMBER.

TuHE GEOLOGY OF THE TALLULAH GorcE. S. P. Jones. [Plates
i eee ae eval sa ona eAc taken

PALEONTOLOGICAL SPECULATIONS. (I): ZL. P. Gratacap-.. 73.222.
Tue PLAN oF THE EarTH AND ITs Causes. (I). J. W. Gregory..

REVIEW OF RECENT GEOLOGICAL LITERATURE.

Jovellania triangularis im Mitteldevon der Eifel, E. Kayser,
119; A brief review of the titaniferous magnetics, J. F. Kemp,
119; The Origin of Kaolin, Heinrich Ries, 120; Igneous com-
plex of Magnet Cove, Arkansas, Henry S. Washington, 121; A
granite-gneiss area in Connecticut, L. G. Westgate, 126; The
origin of nitrates in cavern earths, William H. Hess, 122; Ig-
neous rock-series and mixed rocks, Alfred Harker, 123; The
Sundal Drainage System in Central Norway, R. L. Barret,
123; Bulletin No. 4 of the South Dakota School of Mines, De-
partment of Geology, C. C. O’Harra, 124.

MontHiy AvutHors’ CATALOGUE OF AMERICAN GEOLOGICAL LITERA-
TURE) 24s Oecd ee ee ekeb es os se eee

PERSONAL AND SCIENTIFIC -NEWS..-. coeieee ee ene eee
Geological Society of America, Cordilleran section, 131.
MARCH NUMBER.
Some NoTES ON THE TRAP DixKes oF Georcia. S. W. McCallie.
[Plates) XTI-XTV]. ......00.. ee eee
THE PLAN OF THE EartH AND Its Causes. (II). J. W. Gregory.

ORTHOTHETES MINUTUS, N. SP. FROM THE SALEM LIMESTONE OF
HarropspurG, Inv. E. R. Cummings. [Plate XV].........

Notes ON PETROLEUM IN Catirornia. EF. W. Claypole..........
Some SALIENT FEATURES IN THE GEOLOGY OF ARIZONA, WITH EvI-
DENCES OF SHALLOW SEAS IN Patreozoic Time. W. P. Blake..

Tue Laxe Systems or SouTHERN Pataconta. J. B. Hatcher.
[Plate OXVIA] nec ois oe deen kele ond os oe

590
63

124

129

133
134

147
150

160

Contents.

Eprirorr1AL COMMENT.
PereC TD HemGin RCOLVIVIUIS 2 och. oan. > bd sR so pene cairn aivns +

REVIEW OF RECENT GEOLOGICAL LITERATURE.

Contributions to the Tertiary Fauna of Florida, WV. H. Dall,
179; Geology of the Boston Basin, vol. i. part III, The Blue
Hills Complex, W. O. Crosby, 179; Notes on the Tellurides
from Colorado, Charles Palache, 181; The Analyses of Italian
Volcanic Rocks, H. S. Washington, 182; Occurrence of Na-
tive Lead with Copper and other minerals at Franklin Fur-
nace, N. J., W. M. Foote, 182; Occurrence of Sperrylite in
North Carolina, W. E. Hidden, 182; Thomsonite, Mesolite
and Chabazite, from Golden, Colorado, Horace B. Patton,
183; Beitrage zur Burtheiling der Brachiopoden, F. Huene,
183; Kleine Paleontologische Mittheilungen, F. Huene, 184;
Action of Ammonium Chloride upon Analcite and Leucite,
F. W. Clark and G. Steiger, 184; Chemical Study of the Glau-
cophane schists, H. S. Washington, 184; Mode of Occurrence
of Topaz near Ouro Preto, Brazil, O. A. Derby, 185; Carno-
tite and Associated Vanadiferous Minerals in Western Colo-
rado, W. F. Hillebrand and F. Leslie Ransome, 183; A Con-
tribution to the Natural History of Marl, C. A. Davis, 185;
Composition of Kulaite, H. S. Washington, 187; A Topo-
graphic Study of the Islands of Southern California, W. S.
Tangier Smith, 187; A Remarkable Marl Lake, C. A. Davis,
188.

CoRRESPONDENCE.
Notes on the Kansas-Oklahoma-Texas Gypsum Hills, Charles
RMT Pathe FA ee Lvl won MOE Tate o> =o! «0: shan ais Urm's © womiwte fe es

MontHity AvutTHor’s CATALOGUE OF AMERICAN GEOLOGICAL LITER-
ANUS." Gee AAG 2 tcl a, A

PERSONAL AND ScrentTIFIC NEws.
Lake Superior Iron Trade for the year 1900, 195; Tribute to
Victoria, 197; Billings: Memorial Portrait, 197, etc.

APRIL NUMBER.

Tue Granitic Rocks oF GEORGIA AND THEIR RELATIONSHIPS.
muons ©... Matson. [Plates AVI XTV]. i... ce ewe el

METAMORPHIC ForRMATIONS OF NORTHWESTERN CALIFORNIA. Oscar
ee AISIE CAT Scr L0,. ¢ wie n. <'xitaf OMEN? TSS roy Sloe a: chabt/e, oa e010) 6 %nte'n

ON THE HELDERBERGIAN Fossits NEAR MontTrEAL. CANADA. Charles
“STD A GAELS cee SAE ce 6 Oe Beene per anrane

REVIEW OF RECENT GEOLOGICAL LITERATURE.
The Calcareous Concretions of Kettle Point, Lambton County,
Ontario, Reginald A. Daly, 253; The Granitic Rocks of the
Pike’s Peak Quadrangle, Edward B. Mathews, 254; Geology of

188

190

VI Contents

the Little Belt mountains, Montana, with notes on the Min-
eral Deposits of the Neihert, Barker, Yogo and other districts,
Walter H. Weed. Accompanied by a Report of the Petrogra-
phy of the Igneous Rocks of the District, L. V. Pirsson, 254;
Notes on the Limestones and General Geology of the Fiji Isl-
ands, with special reference to the Taw Group. Based upon
Surveys made for Alexander Agassiz, E. C. Andrews, 256;
Contributions to the Geology of Maine, H. S.. Williams and H.
E. Gregory, 256; Geology in its Relations to Topography, T. C.
Brauner, 257; Researches on the Visual Organs of the Trilo-
bites, G. C. Lindstrom, 258.

CORRESPONDENCE.
On the Age of Certain Granites in the Klamath Mountains,
Oscar FY Fler sWey soc. sicety acum ctteeoathe et ee ee oie
A National Museum for Canada, A, Me Ayes ee ce ere

258
259

MontHiy AutHor’s CATALOGUE OF AMERICAN GEOLOGICAL LITERA-....

BOG 2) Oe i ns aries hs OnaePmus tyr iN AiG wo 6 eho

PERSONAL AND SCIENTIFIC NEWs.
A new Journal devoted to science teaching in secondary schools,
263; Notice of the death of Dr. Geo. M. Dawson, 264; The
Cerrillos Anthracite Mines, 264.

MAY NUMBER.

BrieF BioGRAPHICAL SKETCH OF ELKANAH Buitiincs. Henry M.
Ao. Portrait] o.oo os oe Se ee eee

OricINAL Micaceous Cross: BANDING OF STRATA BY CURRENT Ac-
TION. J.B; Woodworth... (illustrated) Peescisset te enn

A HistortcAL OUTLINE OF THE GEOLOGICAL AND AGRICULTURAL SUR-
VEY OF THE STATE OF Mississipri1 E. W. Hilgard.............

EpitortaL COMMENT.
Pleistocene Geology of Northern and Central Asia............

REVIEW OF RECENT GEOLOGICAL LITERATURE.

Was Mount Royal an active volcano? J. S. Buchan, 313;
Summary report of the Geological Survey of Canada for 1900,
313; Analysis of Emery from Virginia, VW. W. Muller, Jr.,
314; On the constitution of barytocelestite, C. W. Volney, 315;
Examination of sandstone from Augusta County, Virginia, lV.
W. Miller, Jr., 315; Analysis of smithsonite from Arkansas,
W. W. Miller, Jr., 315; Some principles of rock analysis, W. F.
Hillebrand, 315; Analysis of rocks, Laboratory of the United
States Geological Survey, F. WV. Clark, 316; An experimental
investigation into the flow of marble, Ff. D. Adams and J. T.
Nicholson, 316; The Physiography of Acadia, R. A. Daly,
316; The structural relations of the Amygdaloidal melaphyrs
in Brookline, Newton and Brighton Mass., H. T. Burr, 319.

260

284

311

Contents. VIL

MontHiy AuTHor’s CATALOGUE OF AMERICAN GEOLOGICAL LITERA-

ene aerate ee, AG, ott Sa va ae Lek Skewes eee e 320
CorRRESPONDENCE.

Are the Amygdaloidal melaphyrs of the Boston basin intrusive

Geeomemporancous: “M7. Or Crosvy... 2c... ee cece eceeecee 323
PoP CTEM TIRIC NEWS... ci 50 ib. ccc eee ee ce ee ec eee seen en 327

National Museum for Canada; Methods of field instruction in
Geology at Harvard; Neutaconkanut boulder; Bement collec-

tion of the American Museum of Natural History; The Spen-
diaroff Prize.

JUNE NUMBER.

THE ONTARIO COAST BETWEEN FAIRHAVEN AND Sopus Bay. J. O.

Mime Ite pee eam MOC VEL | lor aa ee ee ee 331
Tue E1cHTH SESSION OF THE INTERNATIONAL CONGRESS OF GEOLO-
Cisneee at GMeTGOT. CKSITONe FTGSOM. 200.12 gkieie Del. ste de st tee 335

Two New GENERA AND SOME New SPECIES OF FOSSILS FROM THE
Upper Pareozorc Rocks or Missourr. R. R. Rowley. [Plate

SCA WEIUIU). | ood’ coat acute epee ce aa SRI SE GI edie? en gE a ea se 343
Ore FORMATION ON THE HyYporHESsIS oF CONCENTRATION THROUGH
Sip ame DECOMPOSITION. (Co UR. Keyes: wi... cece anmeige tenes 355

CONCERNING THE OCCURRENCE OF GOLD AND SOME OTHER MINERAL
ROM UGO STN OW AeY SS OHUUEL. COLUIW Seo ge cle ota neue e heln « «eye idee 363

EprrortAL COMMENT.

lsat Cat alomtesr, eta ten Peet fale cee eee ee ed ea oe eae 372
Contributions to the Literature of volcanoes=................ 374
Gilbert's summary history of Niagara Falls.........:..:....- 375
Mite eMart EnidsoneIRivel. saan cece «eetisea nies Fale ebve etal 377

REVIEW OF RECENT GEOLOGICAL LITERATURE.
Phylogeny of the Rhinoceroses of Europe, H. F. Osborn, 370;
Some new and little known fossil vertebrates, J. B. Hatcher,
379.

Montruiy Avuruor’s CATALOGUE OF AMERICAN GEOLOGICAL LITERA-

CORRESPONDENCE.
Are the St. John Plant Beds Carboniferous? G. F. Matthew,
383; The structure of Diamond Head, Oahu, WW. H. Dall, 386.

PERSONAL AND ScreNntIFIC NEws.
American Association for the Advancement of Science, 387;
First description of the geysers of the Yellowstone National
Park, 388; Excursion of Section E, A. A. A. S., 388; Lehigh
University, 3890; Geological trip from Harvard University, 300;
Increased coal mining in Pennsylvania, 390.

oe LIBRARY
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THE

eee RICAN GEOLOGIST.

Vor. XXVII. JANUARY, Igor. No. 1.

BREVITY OF TUFF-CONE ERUPTIONS
By S$. E. BisHop, Honolulu.

PLATE I.

Tuft-cones, of which a number have been formed on the
eastern coasts of the island of Oahu, are produced by the class
of eruptions distinguished as “ explosive.” The semi-liquid
tuff has been projected in a jet or fountain to a considerable
distance and having been driven laterally by the expansion of
the steam and other gases contained, has fallen at some dis-
tance from the vent, building up a cone with a more or less
regular rim enclosing a concave bowl. All the explosive
eruptions actually observed seem to have occupied a very
brief time. The greatest one, that of Krakatoa, was probably
less than one hour in actual emission, although the fall of its
lighter ejecta continued for several hours.

It therefore seems remarkable that an opposite opinion
should have been expressed respecting the eruption which
produced Diamond Head. This typical tuff-cone, lying in
the suburbs of Honolulu, bounds our ocean view to the east-
ward. It was recently examined by Doctor W. H. Dall of the
Smithsonian Institution with especial regard to the age of
the fossil shells found in its debris. In the “Bulletin of the
Geological Society of America,’ Volume 11, pp. 57-60, Dr.
Dall expressed conclusions respecting the age of the crater,
which I feel obliged to controvert. He says:

“The conclusion to which I came was that the whole mass
of Diamond Head had been slowly deposited in comparative-
ly shallow water and gradually elevated without being sub-
jected to notable flexure The ejection of material at first

2 The American Geologist. January, 1901.

must have been intermittent with long quiescent periods to
enable the shore to have become repopulated with mollusks
and corals.”’ A good picture of Diamond Head appears op-
posite page 40 preceding.

It is necessary here to remark upon two serious errors of
observation committed by Dr. Dall. It is true that Diamond
Head was deposited in shallow water, its center being about
one mile outside of the previously existing shore line. I un-
dertake, however, to question the idea that it has since been
“oradually elevated.” Such elevation if it occurred must
have been some 200 feet to have exposed what he calls a ma-
rine formation on its seaward base. Dr. Dall should have ob-
served the total absence of marine erosion around the sides of
the cone, upon the soft material of which the action of the
waves would have been extremely destructive There is also
no trace of such erosion around the evidently older tuff-cone of
Punchbowl, four miles away, nor any elevated beach marks
along the neighboring mountains.

Dr. Dall’s second error of observation was in attributing a
marine origin to the mass of material lying against the sea-
ward base of the crater. That mass is composed of mingled
small angular fragments of tuff fallen from the hights above,
with large quantities of calcareous beach sand. Pervading the
mass are numberless laminated calcareous concretions, which
Dr. Dall has mistaken for coral reef. These fragile laminated
crusts are identical with those forming the interior structure of
our numerous calcareous sand dunes. The layers constantly
vary in angles of dip, corresponding to the formerly varying
surfaces of the dunes. Had the tuff enclosed ever been ex-
posed to the action of the waves, so far from retaining its
angular forms, it would immediately have been ground into
soft mud.

The whole mass is of Aeolian formation. It is simply a
great sand-dune. The contents have been assorted by the
wind, the eastern end being composed mainly of larger frag-
ments of tuff, and the western end, one-third mile away, main-
ly of sand much triturated, and stained by the brown tuff.
The mollusks of Tertiary age enclosed in the mass, as found
by Dr. Dall, may be fully accounted for as having fallen from
the hights with the tuff. They were torn off from the ancient

Brevity of Tuff-Cone Eruptions.—Bishop. 3

submerged reefs and beaches traversed by the shaft of the
eruption. I have found large shells embedded in the laminat-
ed tuff at Koko Head, as well as corals. Farther evidence is
found in the fact that fragile land mollusks are enclosed be-
tween the crusts in great numbers side by side with the marine
shells. Both fell together from the cliffs above. .

My main contention, however, is to prove the absolute im-
_ possibility that a crater like Diamond Head should be a
product of “intermittent ejection” with “quiescent periods,”
even brief ones, or that it could have been “slowly deposited.”
I propose to prove that a cone of such peculiar form and
structure could have been created only by an extremely rapid
projection aloft of its material, completed in a few hours at
most, and ceasing suddenly and finally.

My first proof of this conclusion is derived from the ex-
treme regularity of the elevated circular rim of this cone, such
as could be the result only of a single, rapid, uniform, uninter-
mitted outthrow of the tuff.. Two-thirds of the elevated peri-
meter is part of an almost perfect circle of about 5,000 feet
in diameter, and of a comparatively uniform hight, about 450
feet above sea-level. The tuff is piled up in this regular ridge,
originally rounded on its top, in very uniform quaquaversal
layers or lamniae, whose steepest dip on the outside is about
35°, and much less on the inside of the broad bowl. The
great subaerial erosion discloses the interior structure of the
rim, although it has not obliterated the really delicate sym-
metry of the original form. (See Plate 8, Vol. 11, p. 46.)
The southwest third of the perimeter of the crater is mas-

sive, attaining a present hight of 762 feet. It is severely
wasted by the impact of storms, and was once probably 1,000
feet high. The original rounded summit must have been
considerably to seaward of the present sharp peak. The orig-
inal form may be best understood by comparison with those
of Koko Head and of Lehua island, which are of somewhat
similar form and dimensions, but remain substantially unal-
tered in their rounded summits. The immense enlargement
of the southwest portions of these craters, as well as of many
others is doubtless correctly attributed by W. L. Green to the
action of the strong trade winds deflecting to leeward the lofty
jet of tuff, and piling it up disproportionately on that side.

4 The American Geologist. January, Aaa

With due allowance for the single disturbing influence of
the wind upon the summit of the mighty fountain, it is evident
that the very perfect symmetry of the main portion of the
rim could have been produced only by an extremely regular
fall of the spreading fountain of ejecta at a uniform and un-
varying distance from the vent. Any interruption or inter-
mission would have so disturbed that precise uniformity of
projection as to have piled the falling tuff in irregular posi-
tions. The beautiful symmetry of the crater is a powerful
witness of its sudden and rapid formation. It forbids any
other conception.

My second evidence of the brevity of the eruption which
created the crater-cone is derived from an arithmetical compu-
tation of the time required to deposit the actual mass of the
cone by a fountain of adequate hight to deliver its ejecta upon
the existing rim of the bowl. Data are easily secured for a
sufficiently approximate estimate of the time to show that it
could have occupied a very few hours at most. Let us first
compute the solid contents of the tuff deposited. The average
diameter of the bow! is about 5,000 feet. Two-thirds of the
perimeter is 450 feet high, to which 50 feet may be added on
account of the average depth of sea at the distance from the
shore, where the eruption occurred. The other third of the
perimeter was occupied by a conical mass probably 1,000 feet
high, but standing in perhaps 250 feet depth of sea. Estimat-
ing this cone as 1,250 feet high, with 5,000 feet diameter of
base, its solid content would be about 8,000,000,000 cubic feet.
The contents of the other two-thirds of the perimeter would
be about 5,000,000,000 feet, making with the cone a mass of
13,000,000,000 cubic feet of tuff in the entire crater.

A similar result is obtained by assuming a base equivalent
to 5,000 feet square, and an average hight of 500 feet, which
gives a solid content of twelve and a half billions of cubic feet.
It is evident that such an estimate is sufficiently large.

Now, to have ejected the whole mass in five hours would
have required an emission from the vent of two and a half bil-
lions of cubic feet of tuff in an hour, or of 694,444, feet in
one second. Supposing the vent to havea sectional area of
2,000 feet, which I believe to be much too small, the velocity of
emission would be only 347 feet in a second, which is equiva-

Brevity of Tutt-Cone Eruptions.—Bishop. 5

lent to a theoretical hight of only 1,900 feet of projection aloft.
It is evident that this is totally inadequate.. Assume then only
two hours’ duration of the eruption. This gives us 875 feet of
velocity of emission, equivalent to a hight of projection of
11,925 feet. Such an altitude of the fountain might be ade-
_ quate to the actual distribution of the ejecta to an average dis-
tance of 2,500 feet from the vent. But it must be noted that
the hight attained with the assumed velocity could hardly be
more than two-thirds of the theoretical one, on account of the
resistance from the falling tuff encountered by the ascending
jet. It is also evident that the fountain must have been a
very lofty one for the tuff to have been driven half a mile to the
leeward by even a heavy gale, as so much of it was done in
building up the massive cone.

The real area of the vent can be less accurately estimated.
_ The partially exposed vent of the neighboring crater of Punch
Bowl is apparently fully a hundred feet in diameter. The
only completely open vent of the kind which I have seen is that
of. Kalaupapa at the leper settlement on Molokai. This is a
rocky well with vertical sides reaching down to salt water,
which is 800 feet deep. The diameter of this well or shaft
was, as I remember it, from 100 to 150 feet. Guided by these
data I should consider 5,000 square feet as a very conservative
estimate for the sectional area of the shaft from which issued
the tuff of Diamond Head, instead of the 2,000 feet assumed
above Such increased area would reduce the two hours’ dura-
tion assumed, to 48 minutes. It would be much less if we
allow a greater velocity of ejection, so as to get a hight of the
fountain adaquate to allow of its extensive deflection by wind.
I incline to the belief that the eruption did not last more than
half an hour. It is absolutely impossible that it could have
continued many hours.

These explosive eruptions are of gigantic force and brief
duration.

Honolulu, November 14th, 1900.

6 The American Geologist. January, 100%

POSSIBLE NEW COAL-PLANTS ETC., IN COAL.
PART III.
By W. S. GRESLEY, Erie, Pa.

Plates I1-VIII.
Reference to and Remarks on the Figures in Plate I.

Fig. 1. Portion of a cluster or patch of seed-like bodies, partly in
plan and partly in section, embedded in a fragment ot or-
dinary commercial anthracite (Carboniferous) from Penn-
sylvania. The name or number of the vein or seam, as well
as location, is not known.

Horizontal section of one of the objects—pods or seeds
(? megaspores) in fig. 1. In reality the spotted aspect of
the contents of these black-bordered bodies should be
spoken of as clear, black, compact anthracite as a matrix
to hundreds if not thousands of minute gray specks.

Fig. 3. Magnified appearance of the ? microspores—seed contents—

of these little ? pods.

er
JQ
to

Remarks on the foregoing. Whatever these fructifica-
tions represent they appear to be oblong in form rather than
circular. Along the lower right and along the bottom of the
specimen the pods are seen in oblique section, on account of
the breaking of the coal. Since the blank area “a” shows a
different horizon in the coal from that in which the fossil re-
poses, it is quite reasonable to suppose that the seeds lie be-
neath it, and not less closely packed than seen higher up in
the fig. near “b.” Is there not in the pose of these bodies a
suggestions of symmetry in form or arrangement, as opposed
to a disposition resulting from scattering or accidental ac-
cumulation. While the various pods are not seen to possess
connection by stalks, there is nevertheless among them indica-
tion of such in the shape of coaly filamentose appendages or
inter-twinings suggesting that the fossil represents seeds
synearpous in form rather than individually scattered or ac-
cidentally buried here in a mass together. In this fossil I
see nothing to suggest a cone-derivation for these spores.
May they not have belonged to a water plant?

Other, but smaller and less preserved specimens of very
similar seeds have been met with in the same coal; the exact

*For earlier papers of this series see AMERICAN GEOLOGIST, Feb. 1899,
Get. 1899, and July, 1900.

THE AMERICAN GEOLOGIST, VOL. XXVII, - PLATE ITI.

Fig. 5

STRUCTURES IN COAL.

PLATE Tit:

STRUCTURES IN COAL,

Possible New Coal-Plants Etc., in Coal.—Gresley. 7

character of the enclosing material, being rather dull and
gray, or “bony,” than black or more glossy coal.

Notice how easily the lower part of the specimen fig. 1
might be mistaken for the form. illustrated in fig. 3, plate II,

facing p. 50, vol. xxvi, July, 1900.

Fig. 4. Vertical view showing a patch of ? detached or scattered
ti-radiate spores,? occurring in coal same as fig. I.

Fig. 5. Longitudinal section, ? somewhat oblique, apparently ex-
hibiting a small cone or inflorescence belonging to some
unknown plant embedded in a dark gray lamina of Penn-
sylvania anthracite.

Reference to plate III and remarks on the specimens.

Figs. 1 to 7. Horizontal, or for the most part horizontal, sections of
various pods, seeds, infloresences etc., of several kinds at-
tached to or in such close contact with parts of stalks, twigs
or other extremities of plants that they are probably im situ.
Observed upon the planes of lamination of various speci-
mens of Pennsylvania anthracite.

Fig. 8. Oblique section of a comparatively small ? macrospore, ap-
parently attached at the junction of ribbon-shaped processes.
Pennsylvania anthracite.

Fig. 9. Magnified aspect of some of the ? microspores of the form
fig. 8.

Fig. 10. Exterior of macrospore ? (in this case composed of py-
rite) embedded in anthracite; associated with several other
scattered ones composed of coal. The shape of this fossil
seems peculiar.

Note. If we admit that for the most part those fossils
are fragmentary all that I care to say concerning them is that
we seem to be presented with some five or six different spe-
cies of seeds and ovules, as the case may be, none of which
seem to belong to cones, but rather to meandering, swelling,
branching and sinuous plants. However this may be, these
drawings may serve to direct the attention of other workers
to similar forms, so that eventually their significance may ap-
pear. Since some layers or horizons of the anthracite are
quite crowded with this kind of forms, the plants to which
they belonged were decidedly coal-forming in their nature,.
or as to their substance. ;

Reference to Plate IV, and remarks on the specimens.

Fig. 1. Part of a small patch of what may be seeds composed of a
milk-white substance surrounded by brittle coal. Horizon.

The American Geologist. Jannary, .80%

Bedding plane of coal-seam (bituminous). Loc. What
Cheer, Iowa.

Fig. 2. Tri-radiate macrospores ? with leafy expansions apparently
torn and fragmental. Color, pale brown. Same horizon and
same locality as specimen fig. 1. (See “Triletes,’ Kidston, in
Trans. Roy. Soc. of Edin.; vol. 35; p. 63.)

Fig. 3. A pear-shaped seed—exterior view; seems to be made of
coal. Same horizon and locality as specimens fig. 1 and 2.
(Similar or very similar forms had been noticed by me in
the “‘Pittsburg” coal bed, Pa., and in the “Barnsley Thick”
coal in Yorkshire, England.)

Fig. 4. <A flattened fruit or seed? Cardiocarpon consisting of coaly
material.

Horizon and locality same as the above.

Fig. 5. A three-cornered seed or pod, fossilized it would seem when
about to open along tri-radiate lines. Composed of lime etc.,
and found in a concretion of that material with pyrites, in the
coal bed of What Cheer, Keokuk county, Iowa.

Fig. 6. Nearly horizontal section of what appears to be a pod filled
with seeds. Composed of black carbonaceous material and
pyrite. Horizon. Coal bed. Loc. What Cheer, Iowa. (Dis-
covered by grinding and polishing the material.)

Fig. 7. Horizontal view of a little patch of moss-like filaments
(blackish in color, and embedded in pyrite), enclosing brown
? seeds. Locality, the coal bed at What Cheer, Iowa.

Fig. 8. Horizontal section or view of part of some plant, in or upon
the parts of which are seen little, bright, yellowish, red-coated
seeds, having pearly white nuclei more or less visible. This
and the form illustrated in fig. 7, may be the same plant.
Found in a lime and pyrite concretion in the coal at What
Cheer, Iowa.

Fig. 9 Horizontal section (developed by grinding and polishing a
fragment of a pyrites nodule taken out of the coal at What
Cheer, Iowa) of a seed-bearing inflorescence. a. shows a
seed case or ovule (or epicarp?), to all appearances in place
in this fructification. The specimen seems to be bractiform
in character. The material of the epicarp? is of a brown
color. Other points of interest in this specimen may be
noted by examining the drawing.

Fig. 10. Enlarged view, in perspective, of what seems to be: a
horned or four-cornered seed vessel, perhaps similar to the
one seen at a in fig. 9. This specimen was not found in situ
but lying near others, as though scattered, but in the same
mineralized concretion as for fig. 9. a is the testa or pericarp,
brown in color, and broken away around the seed; b, mem-
brane, copper colored, with surface showing excrescences,
broken and partially removed to show the nucleus or seed;
c. elegantly crinkled or crimped surface of the seed itself,

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PLATE ITV;

THE AMERICAN GEOLOGIST, VOL. XXVII.

SEEDS ETC., IN COAL

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THE AMERICAN GEOLOGIST, VOL. XXYVII, PLATE V.

INFLORESCENCE IN COAL.

Possible New Coal-Plants Etc., in Coal.—Gresley. ‘9

which is, I think, globular in form, peeping through the
broken envelope b. The substance of c is beautifully pearly
white, or of a pale resinous hue, and presumably is petrified
albumen or endosperm.

Fig. 11. Seed, very similar to that in fig. 10, and in the same or a
similar pyritous nodule in the What Cheer coal bed. Devel-
oped by grinding and polishing. Shows flocculent, cloudy
white, central or nucleal material c: golden colored mem-
brane 0D; horned and 4-cornered testa or pericarp a.

Fig. 12. External aspect of another seed very like the one in fig. 10,
but probably a less perfect specimen as to the outer envel-
ope, one of the 4 corners seems to be broken off. Here again
is seen the pearly-looking nucleus where the coverings have
been removed

These seeds are, in the What Cheer coal material, associ-
ated with Lepidodendron, (?) Sphenophyllum, Myclopteris,
and the other forms herein illustrated, e. g. Cardiocarpus,
Pecopterts, etc.

The horizon of the What Cheer coal bed is, by the state geo-
logical survey, considered to be near the base of the coal meas-
ures, or in the “Des Moines” stage of the Carboniferous. (See
Iowa Geological Survey, Vol. TV. Third Annual Report, 1894,
pp. 225-311.)

The pyritous concretions in the What Cheer coal furnish us
with samples of what may be called the raw material of coal
saved from coalification by these concentrations of iron, sul-
phur, lime, etc.

Reference to Plate V. and Remarks on the Specimens.

Fig. 1. Longitudinal section, developed by grinding and polishing
a fragment of a pyritous concretion, of a small bractiform
inflorescence. Locality. What Cheer, Iowa.

Fig. 2. Longitudinal section of another very similar form, possess-
ing stamens in loco natali. From same material, same coal-
bed, and same locality as specimen fig. 1. Does not this
specimen suggest a male flower showing pollen sacs? At-
tached to the stalk of this fossil were two other very similar
flowers (if flowers they can be called), one on each side and
about one-eighth of an inch below it. The stalks, however,
were very poorly preserved, no structure was observed in
them.

Fig. 3. Transverse sectional aspect of one of these cones, very
close to its base.

I'ig. 4. Transverse section—polished, of one of these cones from

~ the coal in Iowa.

The American Geologist. January, 1901.

Fig. 5. Illustrations of stamens, or the ? calyptra of the same, in
another specimen of the same inflorescence.

Fig. 6. Longitudinal section through the central part of a cone
showing several barren ? seed-vessels b at the top of the
stalk a.

Fig. 7. Longitudinal section of a fragment of a twig or branch
showing indications of the peduncular attachment belong-
ing to one of these inflorescences. The form of one twig
seems to have been deeply grooved longitudinally, and was
perhaps of hexagonal section.

Reference to Plate VI. and Remarks on the Fossils.

Fig. 1. View of a group of small conical forms, some attached to
the stalk and branch, as exposed by fracturing a mineralized
nodule (pyrite, lime, etc.) taken from the coal at What
Cheer, Iowa. In this specimen the stalk consists of a soft-
ish, brownish black material and exhibits no organic struc-
ture. In close touch with these cones were several nuts of
Cardiocarpus (Plate VII).

Fig. 2. Longitudinal section of a cone?, and a cluster of what
looks like three seeds within bractiform envelopes; both ob-
jects are attached to the badly-preserved twig. From the
same pyritous concretions in Iowa coal.

Fig. 3. Longitudinal and rather oblique section of the terminal of
a branch or twig, bearing what appears to be a damaged in-
florescence at a. Brought to light by grinding and polishing
the pyritous material out of the coal in Iowa.

Fig. 4. Transverse section through the lower part of the twig fig.
3, showing leaves surrounding the twig or branch, of which
there seem to have been about ten to each node.

Fig. 5. Longitudinal section of what appears to be a terminal of
some twig belonging to still another plant.

Fig. 6. Longitudinal section of part of a seed bearing ? twig of
possibly still another species.

All of the above specimens were discovered in the pyritous

nodular concretions out of the coal-bed at, What Cheer, Iowa.

Reference to Plate VII. and Remarks on the Specimens.

Fig. 1. Longitudinal sectional view or diagram, compiled from
several different specimens, of a Cardiocarpus—-(cardiocar-
pon fruit). The right half of this fruit, seed, or nut, from
the line a b is wholly sectional, and shows indications of
bracts or leaves c enclosing or partly surrounding the ex-
otesta d. Between the latter and the perispermic membrane?
is a zone of calc-spar f. g is the nucleus—the endosperm,
consisting of milky white calcareous material, and exhibiting
a beautiful radiate flocculent structure by a paler tint per-

nae"

PLATE VI.

THe AMERICAN GEOLOGIST, VOL. XXVII.

CONES ETC. IN COAL.

520° LIBRARY

vp, OF TRE

THe AMERICAN GEOLOGIST, VOL.

XXVIT.

PuaATE VII.

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CARDIOCARPUS

Possible New Coal-Plants Etc., in Coal—Gresley. 11

vading the more cloudy one. Near the exterior of the nu-
cleus are beautiful plays of microscopic aborescent pyrite,
which wave about :.n.! creep inwards or towards the center
of the seed. There are near the ape« of g, certain yeliow-
ish brown inclusions or for-nations ji, that may suggest an
embryo. At the base of the seed tray ':e noticed several in-
teresting structural tea! ces pertuliung to the peduncle.

The ‘eft hand haif of the “gure shows a portion of the ex-
otesta removed so as to uring into view the aspect of the
membrane fig. 5, and beneath this membrane at g the sur-
face of the kernel or seed itself appears, which surface is
marked or bears the impress of the pattern or formation sug-
gested by the drawing fig. 5—the membrane e. Observe the
rugged exterior of the outer envelope d. In some specimens
this is seen to be broken and displaced, suggesting something
harder than a fleshy composition.

From mineralized nodules in the coal bed at What Cheer, Iowa.

Fig. 2. Pattern or quasi tessellated appearance of the exotesta d
fig. 1. The color of it is golden brown to greenish gold—has
a bronzy aspect.

Fig. 3. Suggests the charavter of the substance or structure of the
exotesta d. In color is grayish, but often mottled or var-
iegated—black, white, gray, brown, yellowish and reddish.
Near the sides tke cells become smaller.

Fig. 4. Hairy aspect of the inner surface of the exotesta d: greatly
magnified.

Fig. 5. An attempt to depict the pattern or moulded form of the
membrane or thin envelope in contact with the endosperm g.
In substance this membrane is very brittle, thin, and of a
golden trown color. Where the kernel g is widest the pat-
tern is best developed; as the micropyle is approached the
pattern is elongated, contracted and narrowed down as in-
dicated in fig. 1. In reality this pattern consists of little
ovoid knobs within little ovoid depressions.

Fig. 6. Transverse section of the membrane e, so far as showing
its corrugations.

Fig. 7. Oblique view of part of the base of this Cardiocarpus,
showing the hilum 7, and what is perhaps a radicle or cau-
licle « protruding into the nucleus g fig. 1. This radicle?, or
whatever it is, is colored golden brown outside, and its in-
terior substance is white. Does this feature indicate two
cotyledons ?

Fig. 7. a. Loagitudinal section of another aspect of the base or
near to the base of this or another species. I do not under-
stand it. 4 '

Fig. 7. b. View of the base of the nucleus g, fig. 1: ? the hilum.

Fig. 8. Longitudinal section, end view, of one of these specimens
of Cardiocarpus.

I2 The American Geologist. Janek, 2oen

Fig. 9. Longitudinal section of part of possibly a different species
of Cardiocarpus. This specimen, being badly squeezed or
preserved, is difficult to understand. It seems to have pos-
sessed a fibrous exotesta, the character of whose tissue, be-
ing pulled apart, is shown in fig. 10. The pattern on the
inner envelope, and some structures near the peduncle are in-
dicated. This fruit was about twice the size of the Car-
diocarpus fig. 1. Same horizon, locality and material as for
specimens figs. 1 to 8.

I am not aware of any Cardiocarpus showing more internal
organization than do these from the coal of What Cheer in
Iowa, and so possibly they may aid in settling the still open
question—were cardiocarpa seeds?

Though the nodules were quite rich in numbers of the
fruits figs. 1 to 8, I failed to detect any of them attached to
stalk or twig. They lay in the matrix in all positions and scat-
tered; evidently dropped upon or into the vegetable material
enclosing them; in some cases they were in actual contact with
the inflorescenses, Plate V, and with forms shown in Plates
Vi and VIII.

To facilitate reference to authorities on Cardiocarpus, the
following are given:

Q. J. G S., vol. xxviii, plate 27, fig. 4. (an Australian specimen).

Manual of Palaeontology, by A. Nicholson, vol. 2, p. 450.

Cat. Palae. Plants in the British Museum, by R. Kidston, 1886, p. 207.

Report of the Second Geological Survey of Pennsylvania, vol. P,
(Atlas, Coal Flora) pp. 561-574, plate Ixxxv, figs. 32-50, and plate
Ixxxvil, fig. 8.

Palaeontological Botany, by J. H. Balfour, 1872, pp. 65, 66.

Fossil Botany, by Solms-Laubach, 18901, p. 118.

Text-book of Geology, by A. Geikie, 1882, p. 731.

Geological History of Plants, by Sir J. W. Dawson (1888), pp.
80, 82, 153.

Acadian Geology (second edition), by Sir J. W. Dawson (1868),
PP. 459, 460.

Geological Survey of Ohio (Palentology, vol. 1), by J. S. New-
berry, 1873. Plates xli, xliii.

Geological Mag., 1872, vol. ix, pp. 55, 57.

Phil. Trans. Roy. Soc. Fossil Plants of the coal measures, part
vill, by W. C. Williamson, 18 May, 1876, plates xiv, xv, and xvi.

Reference to Plate VIII. and Remarks on the Specimens.

Fig. 1. Fragment of a small Pecopteris, shown more or less in dia-
gram, indicating the form, the shape and disposition of the
pinne, with the exterior venation on the right, and some

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THE AMERICAN GEOLOGIST, VOL. XXVII. PuaTe VILI.

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Fig.19 * tO

PECOPTERIS ETC. IN COAL.

Possible New Coal-Plants Etc., in Coal.—Gresley. 13

anatomical structures on the left. From pyrites nodule in
the coal at What Cheer, Iowa.

Fig. 2. Transverse section of a pinna through a b fig. 1, showing
curling under of the rim or sides of the pinne, and the
position, shape and size of the mid-rib c.

Fig. 3. Longitudinal section through a pinna, near the curving-
under line (c fig. 2), showing cross section of the branching
venation, the curved-under point of the pinna, and the stalk
of the frond at d.

Fig. 4. Another long section of a pinna between its mid-rib and the
curving-under line, showing frond’s mid-rib d, and the
curyed-under edge of the pinna e.

Fig. 5. Rather oblique cross section of a pinna, showing curiously
curved form.

Fig. 6. The aspect of the exterior or upper surface of a pinna.

Fig. 7. Details of the venation near the tip of a pinna.

Fig. 8. Longitudinal section of part of a mid-rib, with branching
or rebranching venation and associated cellular structure.

Fig. 9. View of the underside of a pinna (restored).

Note. In these pyrites concretions in the coal bed at What
Cheer in Iowa, this species of Pecopteris is rather common. It
was by grinding and polishing that the structural details were
brought to light, and I am greatly indebted to Dr. David White
of the United States Geological survey for suggesting that this
fossil be figured, because probably of scientific value paleo-
botanically. Instances of fossilized anatomical structures in
the leaves of ferns are certainly very rare, in fact this is about
the only case I can find or know of.

Fig. 10. Transverse section of part of one of the What Cheer nod-

_ules, showing a portion of a row of pyrite-colored XXX and
dots, separated by or embedded ina blackish substance.

Fig. 11. The aspect of the specimen fig. 10 after grinding and

polishing obliquely. The material was evidently vegetable.
and the structures seem to suggest the palm or the cane.

Fig. 12. Fragment of mineralized cellular vegetable material

(chiefly pyrite), showing pitted and punctate vessels of two
or three kinds. From the coal bed at What Cheer, Iowa.

Fig. 13. Coniferous? wood-cells and medullary ray? material,

composed of pyrite etc., in the coal of What Cheer, Iowa.

Note. The surfaces of these What Cheer pyritous nodules,
while preserving a generally regular outline or contour, are in
reality anything but smooth—they are decidedly rough; the
pyrites mixed with the coal laminz of the seam, and the coal
on the other hand penetrates the pyrites.

14 The American Geologist. Jaaueryese

And in regard to the well-preserved condition of the vege-
table contents of these concretions. it would be very interesting
to know, could the point be determined, whether this vegetable
matter passed through the coaly state between that of the wood,
leaves, seeds, etc., and the pyritous condition—to stone; or
whether the wood, seeds, etc., passed direct into stone pari
passu with the process which converted the vegetable matter
that is now the coal into coal. And this thought leads to an-
other, viz.: Are the same fossils in the coal as we find in the
concretions? The ragged surfaces of the concretions and the
aspect of the fossils where they terminate on these surfaces
(sometimes they grade into coal) suggest an answer in the af-
firmative. But be this as it may, the phenomenon which these
nodules reveal, of so much uncrushed or apparently loose-lying
vegetable tissues and structures as they do, shows with what
intricate subtle and complex processes and ways the conver-
sion of the vegetable matter of the Carboniferous period into
coal, and petrifactions in the coal, was in all probability at-
tended.

Physically and stratigraphically it is interesting to find, as
I have done, the following familiar forms either in or upon
this particular bed of coal; which indicate accumulation of the
vegetal material under marine rather than fresh water condi-
tions: Discina, Natica?, Pentamerus, Lingula, Terebratula,
Pleurotomaria? and Orthoceras.

ON THE PETROGRAPHY OF MOUNT ORFORD.

By JoHN A. DrEssER, Richmond, Quebec.

The Green mountains of Vermont enter the province of
Quebec in several ranges which run in parallel courses and
have a general northeasterly direction, varying in elevation
from inconspicuous hills, or ridges, to mountains ‘upwards of
3,000 feet in hight. One of these ranges, which is a continu-
ation of that to which Jay peak belongs in Vermont, forms
the Sutton mountains; another, appearing first at some dis-
tance on the east side of lake Memphramagog, becomes the
Stoke range, and is a more noticeable feature of the landscape
farther towards the northeast, where it has a greater elevation ;

Petrography of Mount Orford.—Dresser. g

a third forms the line of hills along the international boundary
line between the states of New Hampshire and Maine on the
one hand and the “eastern townships” of the province of
Quebec on the other.*

A little to the east of the Sutton ridge and parallel to it
there is for some distance north of the Vermont boundary
line a series of irregular hills, which have a quite different
origin from the ranges on either side of them. While the lat-
ter have been produced chiefly by the crumpling and folding
of sedimentary strata the former are of volcanic origin, being
the remains of immense outputs of lava, now greatly altered
in character and reduced in amount, which were ejected from
a series of volcanoes or fissure eruptions, probably caused by
the weakening of the sedimentary strata in the process of the
folding which produced the Sutton mountains.

The largest of these igneous masses is that which com-
prises mount Oxford, the area of which is not less than
twenty square miles. If its average hight above the surround-
ing country be estimated at 1,000 feet,$ the mountain at pres-
ent represents four cubic miles of lava which have been ex-
truded in this one mass, and it must also be remembered that a
considerable portion of the mountain has doubtless been re-
moved by denudation, for besides the action of subaerial agen-
cies, it has also suffered from glaciation, even upon the sum-
mit.7

The densely wooded nature of the mountain as well as
its precipitous sides in the only practicable direction of ap-
proach make the mountain difficult of access and render a de-
tailed field examination at present impossible. Yet well known
paths of ascent on the southern side give almost continuous
exposures from the Canadian Pacific railway at the base to the
summit, while, as has been pointed out by Dr. Ells,£ a unique

*Dr. R. W. ELus, Rep. Geological Survey of Cauada, Vol. II, 1886, Part J.
and map, and Vol. VII, 1894, Part J. and map.

§The Canadian Pacific Railway at Miletta Station is 905 feet above mean
sealevel. P. Alex. Peterson, Chief Engineer, C. P. Ry.

Dr. ELts. (op. cit.) found the height of the summit ta be 2800 feet above
sea level by aneroid measurements which were subsequently corroborated by
Mr. Chalmers. (An. Rep. Geol. Survey of Canada, oe x, Fare J.

Messrs. EVANS AND LEROY (Can. Rec. Sci. pp. 225-7, July 1900) find the
total elevation somewhat less, viz: 2650 feet.

+Can, Rec. Sci., July 1900, pp. 223-5.

iAm. Rep. Geol. Survey of Canada, 1894, Part J., pp. 59-62.

16 The American Geologist. Jansasy, 2Oyek

section is exposed by the cutting of the railway which skirts
the base of the mountain between Miletta and Eastman, in a
direction normal to the axis of folding as well as to the strike
of the adjacent sedimientary rocks. On the whole, however,
any observations that can yet be made on the larger petro-
graphical relations of the mountain must still be regarded as
of a preliminary nature.

The rocks of Orford mountain comprise two main divi-
sions. The first, which is found on approaching the moun-
tain from the eastern side, i. e., along the railway from Milet-
ta station, and which is intrusive through Cambro-Silurian
strata, constitutes much the greater part of the mountain
and is an igneous rock of rather uniform character, probably
the product of a single eruption

Its extent along the railway track is as nearly as possible
a mile and a half and it forms the only rock traversed in the
ascent of the mountain by the usual paths from “Orford
crossing.” The second division comprises several rocks of
different varieties both igneous and sedimentary folded to-
gether in a comparatively narrow band running along the
western base of the mountain. It is about one-third of a mile
in width on the railway, and so far as known does not appear
in the more elevated portions of the mountain at all. The
actual contact between these two divisions of the mountain
has not yet been found.

The rock of the first, or greater, mass has a uniformly
green coler, showing gray grains on a freshly broken surface.
Quartz veins are very abund:nt i it and joint planes and
seams are often studded with small quartz crytals. Yellow-
ish-green patches, some times as much as a foot in diameter,
are numerous. They are harder than the normal rock and
stand out in relief on the weathered surface, owing to the
more resistant material of which they are composed ; of which
the mineral epidote appears to be a prominent constituent.
The texture of the rock becomes much finer towards the outer
edge. and also towards the top of the mountain, where the
cooling of the igneous mass would have taken place more
rapidly and under less pressure.

In thin sections examined by the aid of a microscope,
the rock is found to have had its original characters much

en ee

aS Ee a

Petrography of Mount Orford—Dresser. yg

‘obscured by the excessive alteration of its component miner-
als, the primary constituents that remain being comparatively
rare. In specimens from the summit the following minerals
were distinguished: plagioclase feldspar, generally quite tur-
bid from decomposition, though retaining its crystal outlines
and occasionally plainly showing the distinctive multipte
twinning ; aggregates of chlorite, epidote and a light green or
colorless hornblende (?) which are taken to represent pri-
mary pyroxene; an abundance of leucoxene, indicative of the
existence of primary iron ore and indicating its titaniferous
character ; quartz, which is also apparently of secondary ori-
gin.

The arrangement of the feldspars in reference to aggre-
gates of pyroxenic decomposition products, and to one an-
other, is that characteristic of the structure of diabase, to which
the composition indicated above also allies the rock. It is
therefore an altered diabase closely resembling that known
to occur at Owl’s Head,* sixteen miles to the southward.

But it has been said that the rock is coarser in the central
portions, while other variations also appear in it on more de-
tailed examination. In these coarser parts such as are seen
for the first one-third or half of the way up the mountain on
the south side, the original structure was more granular than
that of a diabase. The mineral olivine also appears, either
enclosed in or associated with larger masses of fibrous horn-
blende, while the other mineral constituents are essentially
the same as in the preceding specimens. While a rock of this
composition and structure would be a dioryte, yet as the
nornblende, from its fibrous character, irregular outlines and
the probable presence of a little pyroxene in one slide, is
likely in a large measure uralitic, it would have been origin-
ally a gabbro. It is accordingly best classed as a gabbro-
dioryte , in the sense in which the term was used by Prof. G.
H. Williams} in connection with an apparently similar phase
of the Baltimore gabbros to indicate not only the composition

and structure of the rock, but also its origin.

*““Notes on the Microscopie Structure of Some Rocks of the Quebec Group,”
by Dr. F. D. ADAMS, Rep. Geol. Survey of Canada, 1880-1-2-3, p. 13 A

+Bulletin, U. S. Geol. Survey, No. 28, p. 17, et aliter. The term is similarly
used by F. D. CHESTER, ‘“‘Gabbro and Associated Rocks of Delaware," Bulletin
U. S. Geol. Sur. No. 58, pp. 15-19.

18 The American Geologist. Jantar a

This rock cannot be sharply separated from the diabase
just described, but passes into it gradually, many intermedi-
ate types being found. The two rocks are thus apparently
differentiation products of a single magma and any line of sep-
aration between them could only be arbitrarily drawn.

The rocks of the smaller division on the western side of
the mountain consist, as has been said, of a succession of sedi-
mentary and altered igneous rocks. The following horizontal
section obtained by approximate measurements along the rail-
way between Miletta and Eastman, will help to show the rela-
tive position and extent of the two main divisions as well as
of the subdivisions of the smaller part. The direction of the
section is almost due west from Miletta.

Sedimentary strata at contact with diabase near Miletta..

“I. Diabase and gabbro-dioryte, main part of mountain, 7837 feet.

Graywacke, - - 165 feet.
Ul. Serpentine, ophicaleyte ete... - =. PB Tas
} Sandstone, - - Szase
|Serpentine, ophicaleyte ctec., - - 1567 “ (289) feer;

Sedimentarv slates.

The greywacke is a greenish gray rock containing dis-
cernible grains, some of which show vitreous lustre, while
others do not. In the thin section the latter are found to be
feldspar and the former quartz, while the greenish color is
due to a micaceous-chloritic cement in which the grains are
embedded. It is a clastic rock and a fairly representative
specimen of a graywacke, belonging to the chloritic slates of
Logan,* which is closely associated with the serpentines in
many parts of the eastern townships, now recognized as Cam-
brian} in age. It agrees in all essential respects with speci-
mens from Potton and Shipton, which have been fully de-
scribed by Dr. F. D. Adams.t

The sandstone which occurs in this belt is of a light buff
color and consists of grains of feldspar and quartz of uniform
size and often angular or subangular in form, which are
cemented together by secondary silica, which, though not in
large amount, occasionally shows very y good examples of the

*Geology of Canada, 18638, p. 245.

+Map to accompany Part J, Vol. VII, An. Rep. Geol. Survey of Canada,
ELLS.

fOp. cit. pp. 19-22

Petrography of Mount Orford.—Dresser. 19

enlargement of grains in crystallographic forms. The orig-
inal grans being comparatively fresh in appearance and with-
out any coating or iron the clastic nature of the rock is not
easy to discern in all parts, especially as it is very compact,
and hence the secondary silica is in relatively small amounts.
Small fragments of a colorless mica are to be seen also, which

are unlike any of the micas found in the accompanying ig-

neous rocks. On the whole it is a rock that differs from the
greywacke in conditions of deposition rather than in the
character of the original fragmental material, and is probably
only a phase of it.§

The serpentine is at this place darker in color than is usual
in the eastern townships, presumably from the greater
amounts of chromic iron which it contains. In the thin sec-
tions that have been examined, the alteration of the primary

-minerals has been so nearly complete that the entire field ex-

cept for grains of iron ore, consists either of dull polarizing
serpentine or of the allied secondary form, probably bastite,
which has a fibrous structure with the extinction parallel to
the fibres, and polarizes in rather brilliant colors. It agrees
in all essential respects with the serpentine of Melbourne,
which has been described by Dr. F. D. Adams,* and of
which mass it is practically a continuous part.

Associated with the serpentnes are ophicalcytes and talc
schists into which they appear to pass by rather sharp transi-
tions. .

The ophicalcytes are mottled, light and dark green rock
and are often quite schistose. In the thin section as well as
in the hand specimen, the only essential constitutens are seen
to be serpentine and calcite. The former in some places is
in parallel bands separated by calcite, in others it forms an
irregular network having the interstices filled with calcite.
or it occupies irregular areas in a groundwork of calcite.
The calcite is well crystallized and is free from specks of
graphite or other dark colored inclusions. But it is often
penetrated by small strings or needles or a feebly polarizing
mineral also thought to be serpentine. The boundaries be- -

aed §Logan, loc. cit.
*Op. cit. p. 19A..

20 The American Geologist. January, 1901,

tween the two minerals are very irregular. A few grains of
chromic (?) iron form the only other constituent of the
rock.

The talc schists of slate are soft, greenish gray in color,
and have the distinctive tlose or greasy feel. They are
often finely laminated with a distinct cleaverage. In ordinary
light the thin section appears colorless except for the pres-
ence of small grans of iron or leucoxene, which are some-
what evenly distributed throughout the field. Between
crossed nicols the colorless mineral polarizes faintly in tints
of gray. No crystal outlines are surely distinguishable in it.

An earlier origin is assumed for the western than for the
much larger eastern division of Orford mountain from a
consideration of the following facts, most of which have been
already stated.

The serpentine and other metamorphic rocks are in a more
advanced stage of alteration than the diabase, and are intri-
cately associated with sedimentary rocks of Cambrian age
and may be even older than these. The diabase and gabbro-
dioryte mass, which, as has been said, forms the higher and
greater portion of the mountain, contains little, if any, ser-
pentine and clearly cuts strata recently determined on fossil
evidence* to be of Cambro-Silurian age. Also, the serpen-
tines, which with their associates occur very frequently along
the southeastern side of the Sutton mountain anticlinal simi-
larly associated with clastic rocks, without the presence of
diabase at all, are here in a few instances cut by dykes, while
no dykes have been found in the diabase. These dykes are
too far altered to make it possible to determin their precise
original characters. In the case of three near Orford pond
the minerals augite, or secondary hornblende, are prominent
constituents along with larger amounts of epidote, commonly
in the form of zoisite, and in one case with a little quartz.
They are not very different from the extremely fine, “apha-
nitic,’ form of the diabase as seen near its contact with the
slates about Miletta and hence very probably belong to that
mass.

*Dr. R. W. ELLs, An. Rep. Gecl. Survey of Canada, Part J., p. 38; Dr. H.
M. Ami, ‘‘Preliminary Lists of Organic Remains,’’ Appendix to the above, Part
J., p.133. Dr. Ells also points out that Serpentine rarely if ever occurs in
masses intrusive through strata of Cambro-Silurian age, op. cit. p. 80.

New Areas of Nepheline Syenyte.—Miller. - 21

Accordingly, from the evidence thus far available the ge-
ological history of mount Orford would be briefly told thus:

1. The parent rock of the serpentine was either intruded
in extensive sheets amongst the old stratified rocks, or was
extruded as a surface flow and these subsequently deposited
upon them.

2. These rocks then became very intricately folded to-
gether, and were much worn down by long denudation.

3. An eruption of diabasic material took place along the
eastern edge of the serpentine, which gave rise to the present
mass of the mountain as well as to whatever part of it has
been since removed by denudation. It is probably to this
period, too, that the extrusion of the mountains along lake
Memphramagog, Owl’s Head, Elephantis, Hog’s Back, be-
long, in which “serpentine very rarely, if ever, occurs.*

ON SOME NEWLY DISCOVERED AREAS OF NEPH-
ELINE SYENYTE IN CENTAL CANADA.

By WILLET G. MILLER, Kingston, Ontario, Canada.

In a recent paper Dr. F. D. Adams refers to the probable
occurrence of a large area of nepheline-bearing rocks on the
northeast coast of lake Superior, western Ontario.} During
the summers of 1897 and 1808 the writer was engaged in trac-
ing out some belts of these rocks in eastern Ontario and
showed that they cover a large area in this part of the prov-
ince.£ Prior to 1897 nepheline syenyte was known to occur
in only one outcrop in the province.§ Late in 1896, how-
ever, corundum was found in this part of the province and as
the deposit of this mineral appeared to be of economic value,
the writer was engaged to make an examination of it and to
search for other deposits in the district.

On examining the rocks in which the corundum occurred,
it was found that they were generally either nepheline syenyte
or of some other variety of syenyte. Outcrops of these rocks
were traced along one belt about seventy-five miles in length
and along two other belts of less length. In some parts of.

*Dr. R. W. ELLS, op. cit. p. 80 J.

;Journal of Geology, May-June, 1900.
tReports, Bureau of Mines, Toronto, 1897-8.
§Am. Jr. Science, July, 1894.

22 The American Geologist. January, 70m

these belts the rock in which the corundum occurred was found
to be not the alkali-bearing varieties, the various syenytes, but
the alkaline-earth rocks, anorthosytes.{

From the character of these belts, at their extremities, it
was believed that they could be traced still farther in an east
and west direction.

Late in the autumn of 1899 the writer, while spending a
few hours in the vicinity of the city of Hull, Quebec, discov-
ered a well-rounded boulder containing grains of nepheline,
which confirmed his belief that the belt of these rocks con-
tinued eastward from the province of Ontario across the Ot-
tawa river into the adjoining province, and early in the present
year he discovered nepheline syenyte in place about twenty
miles east of the Ottawa river.

The rock found here was composed essentially of a white >
feldspar and nepheline in grains, some of which had a diam-
eter of two inches, together with a little black mica. The rock
is similar in character to much of that found in the corundum
belt of eastern Ontario. Time did not permit of an attempt
being made to trace out a belt of these rocks to the east of the
Ottawa river, but from what was seen of the outcrops and
from his knowledge of the field relations of these rocks in
Ontario, the writer believes a belt of considerable length exists
in this part of Quebec.

A thin section was made of a fragment of the Hull bounlder.
Under the microscope the rock is seen to be composed of
orthoclase, microperthite acidic plagioclase and nepheline, to-
gether with considerable dark grown mica. The section also
showed several grains of calcite with somewhat rounded out-
lines. This occurrence of calcite in the section is an interesting
feature of the rock, as it was also found to be present in the.
first specimens of the rock examined in Ontario by Dr. F. D.
Adams, and has since been found in specimens of the rock from
a number of other localities in the province. The fact has been
referred to that this carbonate has the appearance of being an
original constituent.*

There are several somewhat puzzling features in connec-
tion with this whole series of nepheline-bearing rocks. Among

{Am. Geol., November- 1899, with map.
*Am. Jr. Science, July, 1894, p. 14.

——
'

New Areas of Nepheline Syenyte.—Miller. 23

these are the great variation in size of grain and mineralogical
composition in parts of the same masses, the presence of grains
of calcite and scapolite, both of which have the appearance of
being original constituents, and the occurrence in some of the
masses of crystals of apatite some inches in length. It will be
seen that in these features these rocks resemble to some extent
certain of the Canadian apatite deposits. In these deposits
water, in a highly heated state, has been considered to be the
chief agent concerned in the deposition. It would seem then
that water may have played a more inportant part in the depo-
sition of the nepheline-bearing series than in the case of other
so-called igneous rocks.

A short time ago the writer made a hurried trip into an-
other part of Quebec about 140 miles to the northwest of the
locality to which reference has just been made, and was some-
what surprised to find an outcrop of nepheline syenyte and re-
lated rocks there. This outcrop is situated on the Kippewa
river about twenty miles to the northeast of the southern end
of lake Temiscaming, which forms the head waters of the Ot-
tawa_ river. The breadth of this outcrop, so far as exposed
above the surface of the water and drift material, is about 400
yards. The rock in the outcrop shows a well-developed schis-
tose structure and a considerable variety of mineralogical com-
position, in a direction at right angles to the strike, as do many
of the outcrops in Ontario. Much of the material has the com-
position of mica or hornblende syenyte, while some of it is more
basic, holding a high percentage of hornblende. A not in-
considerable portion of the rock has the composition of nephe-
line syenyte. The nepheline is in grains of different size up
to pieces three inches in diameter. Some of the hornblende as-
sociated with the nepheline and feldspar is in the form of
masses whose diameter is four inches.

It was observed, in tracing out the nepheline rocks in On-
tario, that they were nearly always associated with crystalline
limestone. No attempt was made, however, to explain this
association.

The first outcrop found in Quebec during the past season
is also associated with crystalline limestone.

In the district lying immediately to the west and south-
west of the Kippewa outcrop which has been geologically sur-

24 The American Geologist. January, 1901.

veyed by Dr. A. E. Barlow and which embraces a territory of
over 4000 square miles, three quarters of which is Laurentian,
crystalline limestone was found in only a few small areas.*
Since this rock was of so rare occurrence in the district which
has been mapped, it was not expected that it would be found
in abundance just outside this area. On discovering the out-
crop of nepheline rock, however, the writer stated to those
accompanying him that it was very likely they would find
crystalline limestone not far off. On proceeding up the river
a short distance, the limestone was found in place.

From the discovery of outcrops of nepheline syenyte over
such an extensive territory in Ontario and Quebec, it would
appear that no Laurentian area of any great size in central
Canada, which contains much crystalline limestone or in other
words which belongs to the Grenville series, is without the
presence of nepheline syenyte and related rocks. ‘This is of
economic importance, in addition to any scientific interest it
may have, as very promising deposits of corundum have been
found at different points, in certain facies of these rocks, some |
of which are now being worked on a comparatively large
scale.

The reason why these rocks have not been discovered in
many places in this part of Canada in earlier years are no
doubt the non-familiarity of many observers with the appear-
ance of nepheline in the field, owing to its comparative rare-
ness in most countries, and its resemblance under some condi-
tions to other light colored minerals. Two instances can be
cited in which rocks containing nepheline were examined meg-
ascopically years ago and in which the mineral wsa mistaken
for quartz. One of these is the case of the syenyte of Montreal
mountain, in which it is said the nepheline was mistaken for
quartz for years. The other is the case of centain outcrops
along the York (Shawashkong) river in Hastings county,
which were examined in 1853 by the late Alex. Murray, and
described by him in his reports as “hornblende rock” and
mica slates.”+ These outcrops while they are more or less
schistose in character, still contain the nepheline in distinct
grains, some of which are of considerable size.

*Report Geol. Surv. Can. I, p. 89, 1897.
+Geol. Surv. Can. 1843-6, Map No.17.

Peneplains of the Ozark Highland.—Hershey. 25

Boulders of nepheline rocks were found many years ago
in the region north of lake Superior.* Dr. A. C. Lawson dis-
covered rocks containing the mineral in the Rainy River dis-
trict, towards the western boundary of the province, some 800
miles west of the eastern outcrops.t It would thus seem that no
really large area of the Archzean in this part of Canada is with-

- out the presence of the nepheline-bearing series. These out-

crops whether they be considered of Laurentian or Huronian
age, may be all looked on as having come originally from the
same magma. Many of the districts, however, in which these
high alkali-holding rocks occur cannot be said to be character-
ized by the presence of these alone. Large areas of rocks
holding a high percentage of alkaline earth metals are of just
as common occurrence. This is especially true of those areas
in the extreme eastern and western parts of Ontario and the
western part of Quebec. At localities on either side of the
boundary between these two provinces, anorthosytes, includ-
ing among others the well known Morin area, occur in large
masses, and from the fact that corundum occurs in some of
these as well as in the nepheline-holding rocks, there seems to
be little doubt that these rocks whose bases, in addition to
alumina, are essentially the alkalis, sodium and potassium, and
those whose basic constituent in place.of the alkalis is chiefly
calcium, are the products of one magma.

PENEPLAINS OF THE OZARK HIGHLAND.

By Oscar H. HERSHEY, Bragdon, Calif.

The Ozark highland comprises all of the mountain coun-
try of Arkansas, the eastern portion of Indian Territory, and
most of the hill-country of Missouri south of the Missouri
river. On the north and west it is bounded by the long east-
ward slope of the “‘great plains” and the Upper Mississippi
region; on the east by the Illinois depression and the Missis-
sippi embayment country, and on the south the sloping plains
of Cretaceous and Tertiary strata stretch from its borders to
the gulf of Mexico. It is separated into two somewhat dis-
tinct uplifts, by the long, narrow Arkansas basin, which is a

*Geol. Can. 1863, p. 480, and Reports for 1846-7.
Bull. Univ. Cal., 1896.

26 _ The American Geologist. January, 1901.

structural and physiographic as well as a topographic depres-
sion.

South of the Arkansas valley, the country is characterized
by the long, narrow east-west ranges of the Ouachita moun-
tains, surmounting a dome-shaped “uplift” or elevated area of
the deformed ‘Tertiary peneplain. These ridges are truly
mountains, and bear a marked resemblance, both in strati-
graphy and structure, to portions of the Appalachian moun-
tain system. They correspond to the Blue mountains and
similar ridges in Pennslyvania, east of the main Alleghany
range.

The synclinal trough of the Arkansas valley has no rep-
resentative in the Appalachian region, but topographically the
valley of east Tennessee is its counterpart. The former sep-
arates the true mountain portion of the Ozark highland from
the northern or plateau division. This latter is what is com-
monly known as the “Ozark uplift,” and many would restrict

the name Ozark to it. The plateau is a great dome-shaped,

elevated tract of the deformed Tertiary peneplain which at-
tains a maximum altitude of about 1,750 feet A. T. in north-
western Arkansas near Fayetteville, and slopes thence gently
to the north and east, and more steeply toward the west and
south. It is surmounted, along a line 20 to 30 miles north of
the Arkansas river, by an east-west range of mountains com-
monly referred to collectively as the Boston mountain. ~ This
corresponds to the Cumberland and main Alleghany ridges of
the Appalachians, and the broad plateau north of it is the
counterpart of the Alleghany plateau.

This close resemblance of the physicial features of the
Ozark highland and the Appalachian mountain region has
frequently been commented on. It is also known that the his-
tory of the physiographic development of the two areas has
been essentially alike in character, as all orographic and epei-
rogenic disturbances of the one have affected the other also.
However, the geomorphology of the Ozark province is not so
well known as that of the Appalachians, and a generalization
of its physiographic features may be of interest, if not also
instructive, to students of American geology.

The Cretaceous peneplain—This, as Mr. L. S. Griswold
has identified it, emerges from beneath the Cretaceous strata

|
:

Peneplains of the Ozark Highland.—Hershey. - 27

in extreme southwestern Arkansas and southeastern Indian
Territory, and rises at quite a perceptible rate toward the
north. The plain-like character is soon lost, and the pene-
plain is represented by long, narrow ridges whose remarkably
even crests constitute the remnants of the ancient plain of
denudation. Still farther north, in Polk and neighboring
counties of Arkansas, and the adjacent portion of Indian Ter-
ritory, the ridges with even crest-line have disappeared, but
the peneplain seems represented in a general way, by the long
east-west mountains rising 1,200 to 1,500 feet above the gen-
eral level of the country, and separated by basins five to
twenty miles wide. Of these ridges, some of the most prom-
inent are the Push, Rich, Poteau, Cavanal, Sugar Loaf and
the Magazine mountains. There are many low passes
through them, and they show a tendency to isolation more
than the Appalachian ridges. Indeéd, several stand alone, in
monadnock-like masses, on the Tertiary peneplain. Only in
a few instances are their summits clearly truncated by a plane
of erosion base-level. Several of the highest have flats of
sufficient extent to afford room for farms on the mountain-
tops, notably the Rich and the Magazine mountains. How-
ever, there is such a general similarity in hight between con-
tiguous portions of the mountain system (and neighboring
peaks) as to leave little doubt that the Cretaceous peneplain is
approximtely represented by the summits of the Ouachita
mountains at an average elevation between 2,000 and 2,500
feet, reaching a maximum of about 2,750 feet on Rich moun-
tain on the line between Arkansas and Indian Territory, and
sloping thence very gently to the west and north, and more
steeply to the east and south.

Between Cavanal, Sugar Loaf and the Magazine moun-
tains on the south of the Arkansas valley, and the Boston
mountains on the north of that broad basin, the Cretaceous
peneplain has been completely destroyed over a width of prob-
ably fifty miles, and extending east and west completely across
the Ozark highland. But it is undoubtedly again represented
in the Boston mountain at an everage elevation of 2,000 feet,
reaching a maximum of 2,257 feet near Winslow on the S. L.
& S. F.R. R. Unlike the narrow ridges south of the Arkan-
sas river, the Boston mountain is a dissected plateau, ten to

28 The American Geologist. Janney ee

fifteen miles wide, trending east to west, bowed slightly along
a central line, but otherwise remarkably even in surface. The
erosion of valleys 500 to 1,000 feet in depth has pretty thor-
oughly cut up this plateau into flat-topped ridges, although
there are undissected tracts of 300 or 400 acres as level as any
plain. The origin of these flats is difficult of explanation
except on the theory that they are remnants of an ancient
baselevel of erosion, a peneplain. Nearly all the ridges reach
this peneplain level.

The Boston mountain is monadnocked upon the Tertiary
peneplain to the extent of about 500 feet vertical. Hence, the
dissected peneplain to its summit is an oldr one. From the
general correspondence in hight between the Ouachita moun-
tains and the Boston mountain, it appears evident that the
same peneplain may be represented in both. Hence, I feel
safe in identifying the Cretaceous peneplain north of the Ar-
kansas river, at a maximum altitude of about 2,250 feet near
Winslow and 500 feet above the main Tertiary peneplain.

Northward from the Boston mountain, the Cretaceous
peneplain is represented by isolated outliers of the main
plateau—flat-topped peaks, sometimes elongated into ridges—
in other words, by a series of monadnocks standing on the
Tertiary peneplain. These are mainly of Coal Measure shales
and sandstones and some might consider them as due to struct-
ural rather than physiographic conditions. However, I am
confident that many of them (especially those whose summits
are truncated) are remnants of the Cretaceous peneplain, so
well represented on the Boston mountain. This gradually
descends toward the north and approaches the main Tertiary
peneplain; near Hindsville, in Madison county, Ark., there is
an interval of only a few hundred feet between them, and near
Eureka Springs, several monadnocks forming small groups
widely separated from each other and far distant from the
main system near Boston mountain, seem to indicate that here
the Cretaceous peneplain has descended to within 100 feet of
the lower baselevel.

Over the Ozark plateau region of southern Missouri, it
is doubtful if any hill can be positively identified as a remnant
of the Cretaceous peneplain. There are a few low monad-
nocks in Stone and Barry counties, which seem to belong to

Peneplains of the Ozark Highland.—Hershey. 29

the same system as those of north Arkansas. One in particu-
lar near Scholten, in the latter county, is a narrow, flat-topped
ridge rising about fifty feet above the surrounding plain.
Coal Measure sandstone and Burlington limestone are so com-
bined in its structure as to make its truncated summit difficult
of explanation under any other than baseleveling conditions.
-I am inclined to believe this is a remnant of the Cretaceous
peneplain, here only fifty feet above the Tertiary. Northward
from here, along the so-called “crest” of the Ozarks they may
be completely merged into one.

The main Tertiary peneplain.—Between the narrow Oua-
chita mountain ridges of south-central and southwestern Ar-
kansas, there are broad basins which, like the inter-montane
valleys of Pennsylvania, represent the Tertiary peneplain. In
the vicinity of Mena, in Polk Co., Ark., the surface is gently
undulating, the streams not having cut much below the orig-
inally very flat peneplain. It is here elevated about 1,300
feet above sea-level, but slopes gently in all directions, partic-
ularly toward the east and south. Southward from Mena,
there are tracts of many square miles, where the surface is a
remarkably level plain. But if we go northward from Mena,
toward the Arkansas river at Fort Smith, after passing Rich
mountain through Eaglegap, we find the floors of the inter-
montane basins quite thorougly dissected by narrow valleys
separating still narrower ridges. These ridges are long and
straight, remarkable for their even crests, and for their equal
hights. In other words, the summit-plane of these ridges
forms as perfect a dissected peneplain as can anywhere be
found on the American continent. This imaginary plain is
absolutely indifferent to the stratigraphy and structure. That
it represents a base-level of erosion common to the entire
Ouachita region is demonstrated by the fact that its slope in
each basin is uniform in direction and degree with that of con-
tiguous basins; that is, were the Ouachita mountains removed,
and the valleys filled to the level of the long, even-crested
ridges of the basins, the whole country would be perfectly
even plain, rising toward a central point near Mena to form:
a dome-shaped elevation of the land—the Ouachita uplift.
This is the main Tertiary peneplain of southern Arkansas and
Indian Territory. Qn it stand the Ouachita peaks and ridges

30 The American Geologist. Janearya sees

like monadnocks and catoctins, and beneath its plane are
trenched narrow basins and canyon valleys of systems to be de-
scribed later.

This Tertiary peneplain emerges from among the moun-
tains to form the very even plain of the Arkansas valley where
for a width of fifty miles or more it is not interrupted by any
monadnocks. Standing on a slight elevation and looking
across the Arkansas valley, the surface appears to be a re-
markably even plain, sloping very gently from the prominent
mountains on the south toward the Arkansas river, quite per-
ceptibly eastward or down the valley in Indian Territory west
of Fort Smith, and very decidedly from the Boston mountain
to the river. In short, the deformation of the nlaia can be
very clearly seen from any point of vantage. Along the axis
of the trough flows the Arkansas river and in its vicinity at
Fort Smith and Van Buren the Tertiary peneplain has no
greater altitude than 600 feet above the sea.

I have said the Arkansas valley appears like a very even
plain, but in reality it is not. The original plain has been
pretty thoroughly dissected, and remains only in narrow
ridges. South of the river, there are the long, straight, even-
crested east-west ridges asin the inter-montane basins.
Many of these ridges are 200 to 300 feet in hight and are
locally known as mountains. In places they are separated by
considerable basins, and the streams cut through them in nar-
row gorges like the water-gaps of Pennsylvania. Indeed, the
topography is that of the eastern Pennsylvania and northern
New Jersey mountain country on a smaller scale.

North of the Arkansas river, the ridges which form the
dissected Tertiary peneplain are less regular in crest-line and
trend prevailingly in a north-south direction. Now an ex-
tremely curious feature of Ozark highland structure comes to
light. Generally the slopes of the peneplains in the Ozark re-
gion are at a very low angle. But here on the southern slope
of the Boston mountain the Tertiary peneplain descends
steeply from an altitude of about 1,700 feet A. T. near Wins-
low to 600 feet A. T. near Van Buren, a distance in an air-
line of little more than twenty miles. This gives the pene-
plain’s remnant-ridges on the north of the Arkansas river a
very decided slope lengthwise or along their axes. In fact,

Peaepiawns of the Ozark Highland.—Hershey. 31

they soon rise up to form the foot-hills of the Boston moun-
tain, and just where the dissected peneplain leaves off and the
mountain spurs begin to be monadnocked on it, is not every-
where easy of determination.

Within the Boston mountain the Tertiary base-level is
hardly recognizable. The valleys on the southern slope are
cut through the interval between the Cretaceous and Tertiary
base-levels and. far below the latter. Those north of the di-
vide are not so deep and hardly reach the level of the Tertiary
peneplain. But in emerging from the mountain on the north,
the newer peneplain is soon encountered, in one of its most
typical and unmodified forms, at an average altitude of about
1,700 feet A. T. Standing on a spur of the Boston moun-
tain, one may look northward for many miles over a country
distinctly lower and apparently a regular plain upon which
rise the outliers of the Coal Measure strata. The plain is
pretty thoroughly dissected by narrow basins and still nar-
rower canyon valleys. In places there are long, narrow, even
crested ridges as in south Aykansas, but usually the drainage
systems are of a perfect dendritic type, and the ridges branch
and re-branch like the limbs of a tree. Near the White river,
the whole country is cut up into a complex of very narrow
ridges and gorge-like, V-shaped valleys, some of which are so
deep that the intervening remnants of the strata are called
mountains; notably the Eureka mountains in Arkansas, and
the Carney mountains in Missouri. The same topography
prevails along the Osage river and, indeed, belts of such ex-
tremely rough country follow all the main streams in the
Ozark plateau region.

That the general upland an ies from the northern base
of the Boston mountain to the Missouri river represents one
and the same dissected peneplain needs no elaborate demon-
stration. Where the plateau is trenched by deep valleys and
even such broad basins as that along the White river in Mis-
souri, the “mountains” on either hand correspond in hight.
The most broken portion of the Ozark plateau, when looked at
from a distance, appears like a plain of remarkable evenness.
Along the main divides, such as that followed by the S. L. &
S. F. R. R. from Lebanon to the Boston mountain, erosion has
not been active, and the streams have not cut deep valleys into

32 The American Geologist. ee

the surface. Here the plain-like character of the country in
the Tertiary era has not been destroyed. The land is gener-
ally rolling, and the “crest” gently ascends and descends, but
it is evident that it is the same plain which is being followed
from end to end.

This Tertiary peneplain descends very slowly from its
maximum of about 1,700 feet in northwestern Arkansas, to —
about 1,500 feet on the Pea ridge, where it is crossed by the
Missouri line, and thence to 1,300 feet near Springfield and
Lebanon. A local uplift of no great extent seems to elevate
it to about 1.700 feet at Cedar gap in Missouri. The White
River valley in Missouri occupies a kind of depression in the
surface of the peneplain. The same Tertiary base-level is
represented by the main ridges of the undulating plain about
Joplin in extreme southwest Missouri, at about 1,000 feet A.
T. It is the same peneplain which forms the general upland
surface of eastern Kansas. Thence southward through In-
dian Territory it may be traced around the Boston mountain
to the Tertiary peneplain in the Arkansas valley, thus escaping
the complication of the curious monocline on the southern
slope of the Boston range.

North of the so-called “crest” of the Ozarks in southern
Missonri, the peneplain continues to descend gradually, and
has no greater elevation than about goo feet at Boonville and
Jefferson City on the Missouri river. The highest hills in
the vicinity of both towns represent it. It is much dissected
all along the Missouri river, but there are enough remnants
left to demonstrate that it is present on both sides of the com-
paratively narrow valley.

The Lafayette base-level—tIn that portion of the Ozark
highland which is south of the Arkansas river, a large part of
the surface has been reduced by erosion below the main Ter-
tiary peneplain to a later and relatively lower base-level. This
Pliocene or late Tertiary cycle of erosion resulted in the for-
mation of broad, shallow basin valleys whose floors were once
quite flat, being composed of the broad alluvial plains of the
streams of that period. They are now dissected by the canyon
valleys of later age, and may easily escape detection except
upon close observation. In approaching the Arkansas river,
these basin valleys become quite pronounced, spreading out

Peneplains of the Ozark Highland.—Hershey. 33

into undulating plains three to five or more miles in width,
and separated by the ridges which constitute the remnants of
the main Tertiary peneplain. One of these small peneplains,
extending westward from Fort Smith, is of particular interest.
for its surface is sheeted with the gravelly alluvium of the La-
fayette formation. This fixes the age of the completion of the
basin valleys as Lafayette,and the plane of their floor
‘throughout the Ozark region may be designated the Lafayette
base-level. In the vicinity of Fort Smith it is about 100 feet
lower than the main Tertiary peneplain, and over all of south-
central Arkansas and east-central Indian Territory it main-
tains a level 75 to 100 feet below the earlier base-level.

Between the Arkansas river and the Boston mountain,
there are, among the hills, certain depressed areas which seem
to represent the Lafayette base-level at a level about seventy-
five feet below the main Tertiary peneplain as the latter is
fixed by the general upland surface. In this region the phys-
iographic features are obscured because of the abnormal South-
ward slope of the country which has especially favored post-
Lafayette erosion. But in northern Arkansas, on the Ozark
plateau, we find the basin valleys well defined. All the prin-
cipal streams flow in valleys which are duplex in character,
being composed of a broad upper trough, beneath the floor of
which is trenched a narrow canyon valley. Along that portion
of the White river which passes through Missouri there is a
basin three to five miles in width, trenched through the Lower
Carboniferous cherty limestones and well down into the
dolomytes of the Ozark series. Its floor is everywhere dis-
sected by the canyon valleys of Ozarkian age. but the main
hill-tops seem to represent a base-level of erosion at a level
between 200 and 300 feet beneath the main Tertiary peneplain.
Passing up the tributary valleys, this base-level is represented
by persistent rock-terraces along the valley sides, some of
which spread out into benches of sufficient width to be occu-
pied by farms. They are especially noticeable on the War
Eagle fork of White river in Arkansas, and the James river
and its tributaries in Missouri. In this region, the rock-ter-
race always occurs at about the same level relative to the main ~
Tertiary peneplain, namely, nearly 300 feet below it.

In the extremely broken and even truly mountainous

34 The American Geologist. January, 1001,

country of the King’s river hydrographic basin in Arkansas,
one may stand on one of the ridges of the Eureka mountains
and look far to the eastward across a vast complex of hills.
Three base-levels are distinetly noticeable, The summits of
many of the ridges form the dissected floors of basin valleys
often several miles in width, and which occupy three-fourths
of the entire surface. ‘This is the Lafayette base-level. Sev-
eral hundred feet higher, the main upland ridges represent the
‘Tertiary peneplain, Looking across their summits the very
hilly country in the far distance apparently merges into a
plain, ‘Che sky-line is even with the exception that a few
monadnocks rise above the peneplain. Some of them are
cone-shaped, but several are elongated into ridges whose crests
are even and summits flat, suggesting the Cretaceous base-
level. In all the Ozark region, this is one of the most instruc-
tive to the student of physiography.

The existence of the basin valleys, rock-terraces, and de-
pressed areas among the hills of the entire Ozark highland
country is a fact which may be verified by anyone who doubts
it. It is also a fact that they have their level irrespective of
the rocky structure, and that the frequent concurrence of the
floor of the basins with the top of centain formations is merely

fortuitous. These basin-floors and rock-terraces often bevel —

the edges of the strata, and they may be observed to pass from
one formation to another without deformation. Hence, there
is every reason to consider them to represent a base-level of
erosion distinct from and considérably later than the main
‘Tertiary peneplain. In many places from the Arkansas to the
Missouri river, this base-level is the site of remnants of an
ancient river alluvium containing a peculiar brown gravel
which is known to be of Lafayette age. The presence of this
tiver-gravel is corroborative of the Lafayette age of the base-
level as drawn from purely geomomphologic evidence,

The vicinity of the White river appears to be the region
in which there is the greatest interval between the main Ter-
tiary and the Lafayette base-levels, here reaching a probable
maximum of 300 feet northward from the “crest of the
Ozarks ;” in the Osage basin and along the Missouri river, the
difference in level is only about seventy-five feet. In this re-
gion the duplex character of the valleys is not so prominent,

|
:
{
|

a .
s

Peneplains of the Ozark Highland.—Hershey. 35

5 but is still noticeable. Near Bunceton, in Cooper county, La-

_ fayette remnants occur about two-thirds of the distance from
the valley bottoms to the hilltops. At this level there are
frequently distinguishable “shoulders” or benches on the hill-
slopes, and sometimes there occur in the valleys ridges whose
truncated summits lie no higher than the Lafayette base-level.

_ When one’s attention is once called to it, it is not difficult to
recognize the “trough within a trough” character of these val-
leys

In approaching the Osage river, the country becomes ex-
tremely broken. The remnants of the Tertiary peneplain be-
come isolated into widely separated elongated ridges and small
flat-topped peaks, none of which approach very closely to the
river. The steep. rocky ridges which bound the narrow and
very crooked canyon valley represent, in a very imperfect man-
ner, the Lafayette base-level, here also about seventy-five feet
below the main Tertiary or “Tennesseean” base-level. That |
the tops of these “river-hills” actually represent a plane of

_ Stream €rosion is indicated by a curious depressed area or val-

ley among the hills about four and one-half miles north of
Lime creek. Here the canyon valley of the Osage makes a
great bend to the southward and encloses a peninsula-shaped
tract of upland. A considerable portion of one of the higher
-Fidges (a remnant of the Tertiary peneplain) is cut off by
a distinct valley or depression in the hills, having a width of
about one mile, a depth of seventy-five feet, and steep slopes
like an ordinary river valley, but whose bottom is dissected
by transverse ravines just as all the remainder of the upland
is. This abandoned valley connects the basin valley above
the great bend with that portion below it, and during the
Lafayette period undoubtedly was occupied by the Osage
river. This valley, the hill-tops along the Osage, and the
remnants of Lafayette stream-gravels in Cooper county, unite
in fixing the Lafayette base-level of erosion in central Mis-
souri at a level only seventy-five feet below the main Tertiary
peneplain, and all that portion of the valleys of greater depth
than this is essentially Ozarkian in age.
In southwestern Missouri, in Jasper and neighboring
counties, the declivity of the streams is not great, and the val-
levs are broad and without the canyon form except very local-

36 The American Geologist. Janndty.: SOMA:

ly The Lafayette base-level would be difficult to detect here.
were it not that a few remnants of the Lafayette stream-gray-
els have been found, notably near Duneweg, about six miles
due east of Joplin. They indicate that to Pliocene erosion may
be charged the upper one-third of the valleys, thus placing the
Lafayette base-level at fifty to seventy-five feet beneath the
main Tertiary peneplain so well represented by the general
upland surface. There are rock-terraces along Shoal creek,
south of Joplin, but they seem of later age than the Lafayette.
A. somewhat similar rock-terrace along the Spring river in
Cherokee county, Kansas, is doubtfully referred to the same
category as the terraces of James river and Flat creek in
Stone and Barry counties, Missouri, known to be of Layfay-
ette age.

In short, that after the completion of the main Tertiary
(presumably Tennesseean) peneplain, there ensued another
(and vastly shorter) cycle of Tertiary erosion, resulting in the
formation of a type of valleys which have been designated
“basin valleys,” because they are broad and shallow and have
gently sloping sides, of supposably Lafayette age in their com-
pletion, may be gathered from evidence scattered all over the
Ozark highland region. This implies, beyond doubt, an ele-
vation of the province in general of an epeirogenic character,
but also to a slight extent orographic, as is indicated by the
250 to 300-foot depth of erosion in the White River basin, in
place of the normal seventy-five to one hundred feet of nearly
the whole remaining portion of the Ozark region. It is this
differential character of the uplift which strengthens the evi-
dence.

Before closing this subject, I desire to remark that the
same or a like system of basin valleys trenched beneath the
main Tertiary peneplain is a recognized feature of the geo-
morphology of northwestern Illinois and contiguous areas,
and are known to me to exist in the inter-montane valleys of
Pennsylvania and New Jersey. May they not be recognized
in the southern Appalachian province, whose physiographic
history is otherwise so nearly like that of the Ozark province?

The Ozarkian valleys—The narrow, crooked valleys
trenched beneath the Lafayette base-level include the erosion
of the Glacial and post-Glacial subdivisions of the Quaternary

2 nei oS a

Peneplains of the Ozark Highland.—Hershey. ‘37

era, but the major portion of their excavation seems to have
been accomplished during that long, early epoch of the Pleisto-
cene period marked by an abnormal elevation of perhaps the —
whole of the North American continent, and which has come
to be known as the Ozarkian epoch or sub-period; hence, for
convenience in discussion, I shall refer to the lower troughs of
_ the Ozark highland as the Ozarkian valleys. The canyon-like
form is a characteristic of them which seems to be persistent
throughout the Mississippi basin, particularly on the lime-
stone areas. It reaches its most typical development in south-
central Missouri, along such streams as the Osage and Gas-
conade rivers and their tributaries. The canyon valleys of
this region have been so often described that I will merely
mention the facts that they are steep-sided troughs winding
about in the bottoms of the basin valleys, have frequently a
mural precipice on one side and a steep slope, strewn with
river-gravel, on the other, and are rarely more than several
times as wide as the streams flowing into’'them. The canyon
valley of the lower Osage averages one-half mile in width and
about 150 feet in depth. Nowhere else in the Ozark highland
are the Ozarkian valleys of much greater depth than the Plio-
cene basin valleys. Throughout the northern slope of the
Ozark plateau they vary between 100 and 200 feet in depth,
while the upper troughs are but half as deep. Yet the latter
are several times as wide, and from their character indicate
a much longer period of erosion.

On the so-called “southern slope of the Ozarks” in Mis-
souri (including the White River basin), the Ozarkian valleys
are essentially of the same character as that of the Osage, hav-
ing the meandering courses and the mural percipices. The
canyon valley of White river in Missouri is scarcely 1,000 feet
in width and 150 to 200 feet in depth. Winding about in a
Pliocene basin valley from three to five miles in width and
nearly 300 feet in depth, the contrast between them is ex-
tremely marked and significant. Nearly the whole of the
James River valley and tributaries, such as Flat Creek valley,
from the main Tertiary peneplain down, has the canyon form
and winding course, but only the lower sixty to one hundred
feet is Ozarkian in age, the 200 to 300 feet above the rock-
terraces being of Pliocene age. In short, in this central por-

38 The American Geologist. Janusex, 200%

tion of the Ozark plateau, while the Ozarkian valleys still oc-
cur in as characteristic a form and as great a development as
in the Osage country, they are quite subordinate to the valleys
above the Lafayette base-level. I wish to have this fact dis-
tinctly understood so that there may be no confusion as to the
origin of the term, “Ozarkian.” It was derived through the
fact that the erosion products of the long epoch between the
Lafayette and the earliest Glacial epoch are so well repre-
sented in the river valleys of the Ozark plateau, but even here
not all the valleys belong to it. In the Ozark highland south
of the Missouri line, the Ozarkian valleys are comparatively
insignificant, and the name would be inappropriate, were it not
for their fine development in south Missouri on the northern
half of the Ozark plateau.

On the War Eagle fork and the main fork of White river
in Arkansas, the Ozarkian valleys are small troughs, twenty
to thirty or even fifty feet in depth and several times the width
of the contained streams, trenched beneath the flat rock-floor
of much larger valleys. In he Boston mountain region, no
valleys can be pointed out as distinctively Ozarkian, although
the bottoms of the deeper valleys on the southern slope must
reach much below the Lafayette base-level. These valleys be-
gan to form at the close of the Cretaceous period, and have
continued uninterrupted to the present day. They had not
been cut down to a base-level before a new uplift occurred and
the base-level of erosion was again lowered. But no sooner
do we go out of the mountain region on the south, where the
Lafayette base-level becomes apparent well up in the hills,

when we find that here the Ozarkian valleys are quite large:

and deep, being comparable with those in Missouri. As the
whole country sinks rapidly to the Arkansas river, these val-
leys become shallower, spread out to a considerable width, and
finally pass into the southern Arkansas type of Ozarkian val-
leys, of which the lower trough of the Arkansas river is a
good example.

Near Van Buren and Fort Smith, Ark., the highest hills
near the river (about 200 feet above it) are remnants of the
main Tertiary peneplain. Midway between it and the river-
level, are the depressed areas, sometimes in terrace form and
sometimes passing inland as gently rolling plains of solid rock

Peneplains of the Ozark Highland.—Hershey. 39

sheeted with the Lafayette gravels, silt and clay (even “orange
sand”). Below this level, the Arkansas has excavated a val-
ley probably three to five miles in width and 100 feet in depth.
This corresponds to the Ozarkian valleys of south Missouri.
On the eroded plain country south of the Arkansas river,
and in the broad inter-montane basins to as far south as the

- Rich mountain, the streams have cut comparatively narrow

valleys beneath the Lafayette base-level. These may average
fifty to one hundred feet in depth and are usually of sufficient
width to afford room for long, narrow farms on their flat bot-
toms. Their sides are steep, but mural precipices are rare.
They are canyon valleys in distinction from the basin valleys
above, but have the canyon form less typically than in south
Missouri. In Polk county, which is on the divide between the
Arkansas and Red river drainage systems and erosion is not
active, the canydn valleys are hardly represented at all, the
streams flowing in shallow depressions or “hollows” on the
peneplain. Indeed, throughout the Ozark highland south of
the Arkansas river post-Lafayette erosion has been insignifi-
cant in results attained, and one almost refuses to believe that
the shallow post-Tertiary valleys of that region are the equiv-
alents of the deep valleys of the Ozark plateau and the upper
Mississippi regions.

The Medern valleys of central Arkansas.—Under _ this
heading are to be discussed certain small canyons occurring
along streams tributary to the Arkansas river in central Arkan-
sas, and which belong to a system, it is beleved, not hereto-
fore identified and defined in any other portion of the Missis-
sippi hydrographic basin. That of the Little Cedar creek,
northeast of Van Buren, was the most typical one observed,
and a description of it may serve for all. The rock formation
is a thin-bedded, calcareous shale of the Coal Measure series,
dipping at a low angle but quite perceptibly toward the south.
In this the creek has excavated quite a large Ozarkian valley,
with steep sides and a flat rock-floor one-eighth to one-quarter
mile in width. This rock-floor is very even and is sheeted
with a few feet of silty alluvium. It bevels the edges of the-
outcropping shales, which dip down stream.

Now, the Little Cedar no longer flows over this old val-
ley floor, but in a tiny canyon, mostly twenty to thirty feet in

40 The American Geologist. January eee

depth, but in places increasing to fifty feet, which it has ex-
cavated in the bottom of the Ozarkian valley. This canyon is
scarcely anywhere wider than the stream, which is itself con-
tracted to a swift mountain brook, and its walls are mostly
perpendicular precipices, along which the rocky strata are
finely exposed, showing that structure has had nothing to do
with the existence of this canyon in the bottom of the vastly
larger Ozarkian valley above. It has the appearance of ex-
treme recency of inception. It is crossed by rock-ledges over
which the stream cascades, and is obstructed by large blocks
which have fallen from the walls. ‘There is a freshness, a
youthfulness about it which I have only observed heretofore
in post-Glacial rock valleys in the Wisconsin drift area.

This recent canyon of probably Modern age (it is form-
ing today) gives out before the Arkansas river is reached. It
is a feature exclusively of the middle course of the Little Ce-
dar (and similar creeks flowing down from the Boston moun-
tain). The smooth valley floor above it could not have been
formed while the stream had its present rapid rate of descent.
This indicates a tilting of the valley toward the Arkansas
river. This, with the presence of the canyon, postulates a very
recent differential uplift of the Boston mountain region. It
will be remembered that earlier in this discussion we found a
remarkable monocline in the main Tertiary base-level be-
tween the Boston mountain and the Arkansas river. The La-
fayette base-level partakes in this unusual deformation almost
to the same extent as the Tennesseean. It was probably dur-
ing the early part of the Quaternary era that this abnormal
slope was mainly produced, but the testimony of the tiny rock-
canyons of Modern age indicates that a movement of a similar
nature has occurred in very recent times and may be in prog-
ress today. Certain peculiarities in the streams of southern
Missouri, and the fact that there has been a wholesale change
in the places of emergence of the springs in times very, very
recent, once led me to believe in a pronounced uplift of the
whole Ozark plateau in the Modern epoch (if it is not in
progress today), and now these modern canyons of west-cen-
tral Arkansas come to light to corroborate the idea, at least as
applied to the Boston mountain region.

The preceding generalizations on the history of the ‘phys-

Peneplains of the Ozark Highland.—Hershey. 4I

iographic development of the Ozark highland, may be briefly
summarized as follows:

1. The entire region was reduced by subaérial erosion to
base-level, forming the Cretaceous peneplain.

2. A great dome-shaped uplift was instituted over the
site of the southern two-thirds of the present Ozark highland.
The amount of elevation was 1,200 to 1,500 feet in west-cen
tral Arkansas, 500 feet in the Boston mountain region, 100
feet along the Missouri-Arkansas line near Eureka Springs,
and nothing from the “crest of the Ozarks” north. The long
Tertiary cycle of erosion again base-leveled this region, form-
ing the main Tertiary or “Tennesseean” peneplain, except that
residuals were left in the Ouachita and Boston mountains.

3. An uplift, general throughout the Ozarks, of seventy-
five to one hundred feet, increasing to 300 feet in the White
River country, enabled a Pliocene cycle of erosion to excavate
the broad basin valleys and reduce much of the country to a
new base-level. The close of this cycle of erosion was con-
temporaneous with the end of deposition of the Lafayette for-
mation in the Mississippi embayment region.

4. Another general uplift, insignificant in amount south
of the Arkansas river, but increasing to a maximum of at least
several hundred feet in southern Missouri, enabled the streams
to excavate the canyon valleys of Ozarkian age.

5. An undoubted local uplift of the Boston mountains
and contiguous areas in the Modern epoch. As most of the
Ozark highland is far above a base-level, it may be presumed
that the late Quaternary elevation has been quite general, but
has occurred so recently, geologically speaking, that only in a
few limited areas are its effects as yet noticeable.

Nov. 15, 1899.

CORRESPONDENCE.

Troost’s SURVEY OF PHILADELPHIA. Apropos of Dr. Merrill’s in-
teresting communication in the December number of this journal I.
beg to call attention to the fact that, safely: housed in the library of
the Academy of Science of Philadelphia along with other bibliograph-
ical treasures, is a copy of Dr. Gerard Troost’s Survey of the environs

42 The American Geologist. Janoprs 27a

of Philadelphia. It is apparently a direct counterpart of the work
noted by Dr. Merrill. It is somewhat remarkable that Lea or Conrad
should have been unaware of the volume in question and that the
Marcous should have been unable to record its occurrence. Recently 2
Philadelphia bookseller offered a copy for sale. In regard to the Ger-
man title mentioned by the Marcous, it may refer to a compilation on
the geology and mineralogy of North America issued in Hamburg
about 1827, to which Dr. Troost among others contributed. As far
as I know this publication contained no map.
S. Harbert Hamilton.

New York ACADEMY OF SCIENCES, SECTION OF GEOLOGY AND MIN-
ERALOGY, OCTOBER 15, 1900. The following notes on the results of the
summer's work by members were presented: 1

Mr. GILBERT VAN INGEN described the work of the party belonging
to the Geological Survey of New Jersey, which, during the past two
summers, has been engaged in tracing the outcrops of the palaeozoic
formations of northwestern New Jersey, and collecting fossils. Of
this party, Mr. Kiimmel, the assistant state geologist, traces the bound-
aries and works out the tectonics, while Dr. Weller, of the University
of Chicago, collects fossils at localities indicated by Mr. Kiimmel.
During July, Mr. van Ingen spent a week with this party in the field
at Newton. Newton is situated on the shales of the Trenton group,
there extensively quarried for slates. To the east is a low ridge of
limestone which presents the same appearance as the Barnagat lime-
stone along the Hudson river. The upper part of this limestone has
yielded trilobites, probably Dikelocephalus, indicating that this por-
tion is of upper Cambrian age. At other localities a trilobite de-
scribed by Weller as Liostracus jerseyensis, shows that the rock there
is also Cambrian—probably of the middle or upper division. In the
vicinity of Franklin Furnace good specimens of Olenellus cf. thomp-
soni were found at localities described by Foerste. Further to the
east of Newton, on the other side of the Cambrian ridge, is a wide
belt of Ordovician rocks,—Trenton limestone overlaid by a _ thick
series of shales. The limestone contains the typical Trenton fauna,—
Rafinesquin, Plectambonites, Pterygometopus etc.—and is very much
like that found at Rosetown, Ulster Co., and at Rochdale, Duchess
Co., N. Y. The shale has few fossiliferous beds, but occasionally one
of the more sandy layers contains Dalmanella testudinaria, Plectam-
bonites and Rafinesquina, the same combination found in the Ejudson
shales at Poughkeepsie, and at Rondout. At one locality was found
a fauna with Ampyx and Harpes. In eastern New York these genera
of trilobites are found only in the Chazy limestone, and the discovery
is of great interest in that it indicates the presence of this formation
at a distance of almost 250 miles south of what has hitherto been
recognized as its southern limit. Further to the northwest, along the
Delaware river, were found the Silurian and lower Devonian forma-
tions. The finest section is seen in the face of the cliff of the old
Nearpass quarry, about five miles south of Tri-states where all the

‘Correspondence. - 43

formations from the upper Ordovician to the Esopus shale of the
lower Devonian appear, with numerous fossils. At Otisville the
Shawangunk grit is finely exposed in a large quarry. All the evi-
dence at hand points to the conclusion that this formation, of a thick-
ness of at least a thousand feet, was formed as a flood plain deposit.
Its characteristics, except color, are the same as the New Jersey and
Connecticut valley Jurassic sandstones. Ripplemarks, sun-cracks, cross-
bedding, channel-fillings etc., are abundant. In the railroad cut west
of Otisville the grit lies upon the Hudson shales, with coincident dip.
On the contact there occurs a few inches of clay, next to the shale
is quite free from pebbles, while next the grit it is filled with quartz
pebbles. This was interpreted to be residual clay caused by the de-
composition of the shale, through sub-aérial agencies, before it be-
came covered by the grit. The old notions regarding rock formation
required the presence of a body of water in which the sediments
might be deposited. Several of the geological subdivisions showed
characters which would not have been present had these formations
been laid down under water, for this mode of origin results in a
sorting of the rock-forming materials, and no sorting is detected in
these grits. Flood plain deposits are very irregular, both as to strati-
fication and sorting of materials, and these features are well exhibited
in the grits. Other formations that are probably flood-plain deposits
are parts of the Potsdam sandstone in eastern New York, the Medina
sandstone, the sandstones of the Catskill group, and many of the
sandstones of the coal mesures of Pennsylvania and the Mississippi
valley—in fact the geater part of the “barren measures.”

Dr. THEopore G. WuireE described his detailed study of the faunas
of successive strata of the Lowern Ordovician in the Glens Falls, N. Y.,
section, and their relations to similar studies along the lake Cham-
plain valley to the north, and the Mohawk and Black River valleys
to the west. The section forms a low anticline along the shore of
the Hudson. At the base is seen the Calciferous sandrock, con-
taining Opsileta and fucoids. Conformable upon this is a layer a~
few inches thick, of barren black shale, which is very much crushed,
and then the same beds of the ostracod, Leperditia, and their asso-
ciated corals and peculiar forms of Strophomena, as have been found
in the lowest Black River zones on Button island in lake Champlain.
The zones of Parastrophia and Triplesia occuring near this portion
of the series in localities to the north and west, were not found here.
The succeeding coral beds of Columnaria were well developed. Above
these are the cross bedded gray beds, which in some recent report
have been considered to represent the Birdseye limestone, which
seems to be lacking in this locality, unless met with at this unex-
pectedly high position. The upper portion of the section, which is of
lower Trenton age, shows no unusual forms. The tendency of the
lowest and the uppermost portions of the Ordovician sections in the
region to wear away and appear wanting, owing to their. prevailing
softness, Was commented on.

44 The American Geologist. January, 1901.

Dr. Henry S. WASHINGTON read a paper on “The Rocks of Lake
Winnepesaukee, N. H.,” as a preliminary report on work done by
Prof. Pirsson and himself on mount Belknap and Red hill, near
lake Winnepesaukee, N. H. The rocks of mount Belknap are shown
to be prominently a quite uniform alkali syenyte, which is cut by
many dikes of camptonyte and allied rocks, and of bostonytes, aplytes,
and syenyte porphyries. These dikes also cut the surrounding por-
phyritic gneiss. At one place, near the border, is a mass of basic
hornblende-gabbro, with large poikilitic phenocrysts of brown horn-
blende. A syenyte breccia also occurs. At Red hill similar syenyte,
formerly described by W. S. Bayley, occurs on the summit, while to-
ward the periphery, nepheline appears as a constituent, and a true
foyayte is developed. The massif is also cut by dikes, both camp-
tonitic and syenitic. The region is to form the subject of a petro-
graphic study by the two geologists in the near future.

Proressor DanteL S. Martin described a visit which he paid to
the noted mineral locality at Haddam, Maine, during the summer.
He described the manner in which the choicest specimens occur
there, in veins of albitic pegmatyte, with tourmaline, muscovite and
quartz along the contact with the wall of gneiss. The mica plates
along the contact are often two feet in diameter.

Dr. A. A. JULIEN in his paper “The Geology of Central Cape Cod,”
reviewed the opinions of Mitchell, Davis, Shaler and others on the
geology of cape Ann, with especial reference to the district from Chat-
ham to Yarmouth. In the stratified deposits of sands and gravels
which underlie the plains south of the morainal ‘“‘back-bone” of the
cape, the more frequent intercalation of clays was pointed out, and
their occasional disturbance and flexure. Striated pebbles, although
much water-worn, are quite largely interspersed. The discovery of
true glacial silt at some depth, in one locality, indicates that the ice-
sheet there rested, instead of floating. The kettle-shaped hollows and
pond-basins were shown by the speaker to be largely connected with
the damming of surface streams, and some observations on the pre-
glacial drainage valleys and topography were discussed. The identi-
fication of certain transported fragments of quartz-porphyry with
outcrops of the same near Marblehead indicates a pre-glacial movement
from N. W. to S. S. E. To the fifteen changes of level which have
been recorded, a final small elevation probably should be added, judg-
ing from the low terrace along this part of the coast. Examples of
the facetted pebbles were exhibited and provoked considerable dis-
cussion among those present, as to the origin of these pebbles.

Pror. RicHArD E. Dopce recounted his pleasure in visiting the
region of the Colorado canyon, during the past summer, in company
with a party, and finding the physiography so graphically illustrated
in the drawings in Powell’s reports, to be a most faithful and non-
diagrammatic portrayal of the features themselves. He then de-
scribed the striking examples of gigantic geo-physical results seen
in the Great Kaibab anticline, the Grand Canyon itself and the Kaibab

Correspondence. 45

plateau and its faults. He also described the appearance of the great
basin of “Lake Bonneville.”
Remarks on foreign localities visited during the summer, were
made by Prof. J. J. Stevenson and Dr. E. O. Hovey.
THEODORE G. WHITE,
Secretary.
A SINGLE OCCURRENCE OF GLACIATION IN SIBERIA. During three sea-

_ sons’ professional work in Siberia I have been constantly on the out-

look for signs of glaciation. It seems almost an anomaly that in a
country covered for fully half the year with snow and ice, there
should be found no glacial remains. Yet such is the case, in the great
majority of instances. In European Russia, north of latitude 63 de-
grees, glacial drift, moraines and drumlins, have been found by the
Russian geologists, as indicated on their maps, although specific ref-
erences to their discoveries are rare. So far as is known the glacial
indications do not extend over into the great northern plain of Si-
beria. The numerous lakes scattered throughout, not only the Ural,
but the whole of west and central Siberia have been sometimes
referred to as of glacial origin. A little close observation of these
bodies of water is, however, sufficient to convince anyone that their
origin is due to a different cause.

In the Steppe region, lying to the south of the Trans-Siberian
railway, and extending from the Ural eastward for many thousand
miles, until it merges with the Great Gobi desert, there are numer-
ous topographic features, which would, by a hasty observer, be laid
to glacial origin. Small mound-like hills, frequently beautiful in
their dome-like symmetry, lie scattered over the treeless undulating
plain. I have been led a mile or more off my route, by a desire to
examine closely such occurrences. In every case they have proved to
be merely curious forms assumed by the rock itself in process of
erosion. In this same region of the Steppe, the presence of numerous
lakes helps to bear out the deception, but when it is found that these
are merely the remnants of former and greater lakes, many of them
being salt at the present day, and that they have not been dammed,
but merely occupy depressions in the gently rolling prairie, the
glacial supposition must of course be abandoned. The Caspian is the
most tremendous example of this kind, then come the Aral sea and
the Balkash lake. In the case of lake Sheero, 200 miles to the west
of Minnisinsk, I noted, surrounding it successively, at various hights
up to 75 feet, rings or old shore-benches, each marking a stage of the
lake’s history. So gradual are the slopes in the Steppe that the last
and highest of these rings was at least three miles away from the
present water’s edge.

In a valley of the Altai mountains, on the head waters of the Tom
river, there was a most remarkable case of pseudo-glacial topography.
While riding up the center of the valley, I saw, making off from the
steep side of the mountain, what appeared to be a glacial esker. It
was perhaps 500 ft. long, 40 ft. in hight, with a width of 60 ft. and

46 The American Geologist. January, 1901.

possessed the rounded, ridge-like summit characteristic of this spe-
cies of glacial topography. Its side had been broken away, and from
the distance, about 600 ft. at which I saw it, the appearance was that
of sand. Such a phenomenon in a region in which I had looked in
vain for glacial signs was a novel and startling one, and I hurried to-
ward it to make sure. In truth the material of which it was composed
was sand, and I could bury my pick to the handle end in it, but alas
it was a fine even grained dioritic gretsen, nothing else. It was in it-
self a remarkable form of dike weathering and interesting on that ac-
count, but as regards glaciation it was only another of the negative
signs of which I had accumulated an extensive category.

The Bazaika Creek valley, about 15 miles to the southeast of
Krasnoyarsk, and across the Yenesei river from that city, furnished
the only evidence of a fair sized glaciated area of a former age which
I have seen.

Here is an area of 100 square miles or so, enclosed by high rock
walls of granite, and sedimentaries, in which, although of purely lo-
cal origin, and confined to local effects, glacial conditions have ob-
tained. Drumlins of most perfect form may be found in the bottom
of the valley, near the Bazaika creek and they extend up to a hight of
600 or 700 feet on the side of the mountain. The glacial cirque topog-
raphy, so common in the high Rockies, has here its development on
a very large scale on one side of the valley, in such a manner that a
large amphitheatre is formed, along which the creek makes its way for
a distance of ten miles. At the upper end of this stream, some sixty
miles from its junction with the Yenesei, it is evident that a glacier
must have existed whose detritus now encumbers the valley. Near
the village at the base of the valley, inside a long spur of limestone
which separates the creek from the Yenesci, lies on one side a beauti-
fully bedded saud-plain, now nearly cut through in section by the
stream itself. Such occurrences as this are too rare in Siberia not to
attract attention, and although I was unable to find confirmatory evi-
dence in the form of scratched pebbles, and am therefore open to the
charge of assertion on non-conclusive evidence, yet so unusual an oc-
currence in Siberia, a non-glacial country, deserves a mention.

In the high Altai the cirques at the head of the valleys, such as
occur in Colorado, due to present freezing, melting and refreezing con-
ditions, are common and may of course be called minute results of local
glaciation. Present glaciers exist also in the Altai on the head streams
of the Irtish river, near the Mongolian border. They occur, however,
in mountain valleys, as in Switzerland, at hights of 10,000 feet, and
are purely local in their effects.

In east Siberia, the gold-placer industry has led to a considerable
study being made of the gravels which there encumber the valleys to
depths varying from 10 to 150 feet. Their subangular character has
led some observers to refer their presence to transportation by glaci-
ers. From my own observations on the gravels they do not appear to
me to have come from foreign sources. Their material can always

Review of Recent Geological Literature. - 47

be traced directly to the immediately enclosing hills. In no case have
I ever found a scratched surface. The gravels are merely immense
quantities of rubbish which have slid into the valleys when the moun-
tains were of greater hight, have become covered in a comparatively
short time with a carpet of turf and peat, due to the constant periodic
growth and rotting of the almost tropical Siberian vegetation, and have
thus lain there undisturbed, the gentle grades of the present streams
not being sufficient to clear the valleys of these masses of detritus.
Under any other than Siberian conditions, perhaps such thick beds of
sub-angular and even angular irregularly disposed gravels might not
be possible. A discussion of these conditions is, however, one that
may be prolonged to a considerable length, and properly forms the sub-
ject for separate consideration.

Berlin, October, 1¢oo. CHESTER WELLS PURINGTON.

REVIEW OF RECENT GEOLOGICAL
LITERATURE.

Ueber Aulacamerella eim neucs “Brachiopodengeschecht: VON FRIED-
RICH Baron HoyNninGEN-HUENE (Verhandlungen der Kaiserlischen
Russischen Mineralogischen Gesellschaft zu Petersburg. Zweite
(Serie. Band xxxviii, No. 1.)

On the ventral valves of two species of brachiopods from the higher
Lower Silurian (Ordovicean) of the Baltic provinces Baron Huene has
founded the above genus with the following diagnosis: Ventral valve
more or less convex, smooth or concentrically longitudinal, keel-like
median fold. Beak almost entirely atrophied. Pedicle opening unknown.
Inside there is a large triangular platform, without median support, con-
nected at the sides with the shell. Hinge-border slightly raised; hinge
teeth rudimentary or lacking. Dorsal valve unknown, apparently flat
or concave. Two species are known. The most remarkable peculiarity
of this genus is the large even platform, with a concave space under-
neath. In this connection comparisons are made with Merista (?)
cymbula Day, and for the medium plate or septum with Orthisina (Clit-
ambonites) diversa Shaler. Comparisons are also made with Camarella
and Syntrophia.

Five figures in the text and a plate of figures of the two species of
the new genus are given. G. F. M.
Supplement su der beschreibung der Silurischen Craniaden der Ost-

seelander. By the same author and published with the former

article.

This is a continuation of Baron Huene’s work on the Craniade
which appeared about a year ago and was reviewed in this journal. In
this are described a number of new species, Pholadops, one species,
Philhedra, five species, (and notes on two others already described),

48 The American Geologist. January, 2002.

Eleutherocrania (new mut.), Pseudocrania, notes on six species al-
ready described. Pseudometoptoma, notes on two species already des-
cribed.

A table of the vertical and horizontal distribution of the forms of
this family is given and following this some interesting remarks on the
systematic place of Pholadops. A few paragraphs also are devoted to
the changes which occurred in Philhedra from its first appearance un-
til it gave place to Craniella and Eleutherocrania in the Horizon F. 2.

There are six text figures and three plates in illustration of the
species treated of in this article, which add materially to its value.

G. F. M.

A text-book of important minerals and rocks, with tables for the de-
termination of minerals. By S. E. TrrtMANn. Octavo, pp. 176, $2.00.
John Wiley and Sons, New York, 1900.

After a brief account of the crystal systems, and of the common phy-
sical and chemical properties of minerals, the author gives brief gen-
eral descriptions of eighty-seven minerals or groups of minerals, especi-
ally adapted to amateurs and economic mineralogists. Each mineral
description is followed by a statement of the uses and localities where
the mineral is most abundantly found. The tables for the determina-
ion of minerals are compact and handy, the primary divisions being
based on color. They provide for the discrimination of 135 species.
Part II. is devoted to a condensed description of common rocks. The
work is adapted to an elementary course in mineralogy in schools and
academies. It is not at all encumbered by technicalities nor by symbols.

N. H. W.

The Progress of Mineralogy in 1899, an analytical catelogue of the
contributions to that science during the year. By S. Harsert HAm-
ILTON and JAMES R. WirHrRow (Bulletin No. 2 of the American
Institute of Mining Engineers, 1900.)

This publication renders a distinct and noteworthy service to min-
eralogy and to mineralogists. It is the only one of its kind that we
know of in the English language. It is not restricted to the United
States, nor to English literature, but embraces all countries and lan-
guages. It is, however, confined to literature that was received in Phil-
adelphia prior to the beginning of 1900. It is divided into seven essen-
tial parts, each part arranged alphabetically by authors’ names, viz.:
New minerals, new meteorites, new elements; chemical mineralogy;
new analyses, determinations, methods etc.; physical mineralogy; new
forms, determinations, crystallographic studies etc.; general mineral-
ogy; new occurrences, economic mineralogy etc.; lithology; new rocks,
petrographical descriptions etc.; bibliographical, historical etc.; new
books, new apparatus etc.

In order to get this literature catalogued the authors have consulted

175 different serial publications from all parts of the world, a fact

which shows that a journal devoted exclusively to mineralogy should be

well supported and a great advantage. Besides its own articles such a

journal should annually contain such a document as this. N. H. Ww.

Review of Recent Geological Literature. .49

New Species of Cambrian Fossils from Cape Breton. By G. F. Mart-

THEW. (Bulletin, Nat. Hist. Society of New Brunswick, vol. iv,

Dp. 219.)

Under this head Dr. Matthew has described a number of Upper
Cambrian species of trilobites and brachiopods that are of consider-
able interest.

A good deal is made of the internal character of the shells of the
_ brachiopods, which are carefully described. The species belong to the
genera Lingulella, Lingula ? Acrotreta and Schizambon. The example
of the last genus is a small species more orbicular than the type, and of
interest as carrying the genus back to Cambrian time. (The typical
form described by Walcott is of Ordovician age.) The Acrotreta is
remarkable for the heavily truncated mould of the ventral valve, and
for the unusually strong medium septum of the dorsal valves.

Among the trilobites the largest species is a Parabolina distinct
from others in the strongly arched front margin of the head shield.
A very remarkable form is a species of Sphaerophthalmus, carrying a
very large flat genal spine, differing from S. alatus in this and other
respects. An Agnostus of generous size is a Canadian mutation of 4
trisectus Salter; it is peculiar in having a tubercle at the end of the
rachis of the pygidium, and in other respects. These trilobites are of
the Peltura fauna; the brachiopods chiefly of this fauna and that of
Dictyonema (D flabelliformis).

A plate with figures of the species and mutations described accom-
panies the article. N. H. W.

The Action of Ammonium Chloride upon Natrolite, Scolecite, Prehnite
and Pectolite; by F. W. CLarK and GEORGE STEIGER. (Am. J.
Sci., 160-345-351.)

The present paper is one of a series having for an object the study
of the chemical constitution of certain silicates. The minerals were sub-
jected to the action of ammonium chloride in sealed tubes at a tempera-
ture of 350°, and the resulting products analyzed. The action of a
boiling, 25% solution of sodium carbonate was also tried on them.
Both natrolite and scolecite are unattacked by the sodium carbonate
solution and yield with the ammonium chloride the same compound
(NH4)e2 Ale Sis O10, which is a simple replacement of the bases and
acid hydrogen of the minerals by the (NH4) radical. From these facts
and anentirely new and complete analysis it is concluded that the two
minerals are salts of the same silicic acid Hg Sig O10, and that their
formule should be written Nae Ale Sig O10 .2 H2O for natrolite, Ca Al?
Sig O10 . 3 H20 for scolecite instead of the previously accepted orthosil-
icate formule Ale (Si O4)3 Nag Ha, and Alz (Si O4) Ca Ha . H20 respect-
ively. Prehnite suffers no change when treated as above and is there-
fore of different structure. Pectolite, a meta-silicate Na H Caz Sig Og,
although attacked strongly by the chloride, did not yield results leading
to any new or more definite conclusions as regards its structure.

CG; How.

50 The American Geologist. Stereo

Chemical Composition of Turquoise; by S. L. PENFIELD, (Am. J, Sci.

160-346:350.\

The article records a re-investigation regarding the chemical com-
position of turquoise. A new analysis was made on material exception-
ally suitable for that purpose. From the results thus obtained the
author shows conclusively that the mineral is to be regarded as a deriv-
ative of the ortho-phosphoric acid in which the hydrogen atoms are
largely replaced by the univalent, isomorphus radicals Al(OH);
Fe(OH)’, and Cu(OH):. The formula may be written [AI(OH)s,
Fe(OH)2, Cu(OH), H]3s POs. The radical Al(OH)? always predomin-
ates. Acareful consideration of former analyses shows them to bein
close agreement with the results just mentioned and wholly disproves
Clark’s interpretation that turquoise is a mixture of the molecule
AleH POs (OH)4 with finely divided iron and copper phosphates as
impurities. C.,H. W.

A new Meteorite from Oakley, Logan County, Kansas, by H. L. PREs-

Ton. (Am. J. Sci., 160-410-412.)

The meteorite, which is the eleventh one reported from Kansas,
weighed 61 Ibs. 10 0z. and was 712 x 10x 12 inches in its greatest di-
ameter. It consists of ‘“‘olivine and enstatite chondrules imbedded in a
very irregular groundmass of the same material, with numerous par-

ticles of iron and iron sulphides.’’ An analysis gives its composition as
follows;—metallic part, Fe 12.76%; Ni + Co 1.68%; silicates, 85.56%;
total, 100%. Cc. H. W.

Cambro-Silurian Limonite Ores of Pennsylvania; by T. C. Hopkins
(Bull. Geol. Soc. Am., vol. 11, 475-502.)

Extensive deposits of iron ores occur as irregular pocket-like de-
posits in the residual clays of the Cambro-Ordovician limestones and
slates of eastern and central Pennsylvania. The ores consist of the
hydrous oxides of iron, chiefly limonite, associated with manganese
ores, wavellite, quartz, chert and fluorite. The ores appear to have
been derived from the original iron content of the limestones and slates,
by a leaching and concentrating process in which carbonic and
organic acids together with oxygen took part,- In position the ores
favor the contact of the limestones and underlying slate. Cc. H.W.

Chemical Composition of Sulphohalite: by S. L. PENFIELD. (Am. J. Sci.,

160-425-428.)

Considerable doubt as to the existence of the mineral sulphohalite
recently described and assigned the formula 3 Naz SO, 2NaCl, having
arisen by reason of the failure of several investigators to make an arti-
ficial salt of like composition, the re-investigation of the species described
in this article was undertaken with the result that another constituent,
fluorine, was discovered and the composition represented by the formula
2 Nae SO4 2 Na CINaF assigned to the mineral. It is interesting to note
that sulphohalite was associated with another triple salt, the mineral
hanksite 9 Naz SO4 2 Naz COs K Cl. Cc. H. W.

Review of Recent Geological Literature. 51

Siliceous Calcites from the Bad Lands of South Dakota; by S. L. PEN-

FIELD and W. E, Forp. (Am. J. Sci, 160-352-3541, with Pl.)

The crystals are rough in appearance, but show with some distinct-
ness characteristic calcite forms. In chemical composition the crystals
resemble the siliceous calcites from Fontainebleau, containing 40% of
calcite and 60 ofsand. The sand grains at times attain the size of small
pebbles. It appears that these crystals represent a phase of sandstone
formation where the calcareous cement was able to crystalise and pre-
- serve its external crystalline form. Cc. H. W.

Granites of Southern Rhode Island aud Connecticut, with Observations
on Atlantic Coast Granites in General. By J. F. Kemp. (Bull.Geol.
Soc. Am., 10, 361-382.)

All the granites described are biotite granites, muscovite, though
present, being very subordinate and hornblende failing entirely.
The following types are recognized: Westerly gray, Westerly red,
Stony Creek red, Stony Creek gray, and Lyme pink. The Petro-
graphic descriptions of these types and of the contact phenomena
and basic inclusious as well as of the associated apatite and pegmatyte,
are followed by a discussion of the chemical composition based upon
six analyses, four of which are new. The silica is quite uniform,
varying from 68.40 to 73.05, but with only one below 70 per cent.
The Rhode Island granites run somewhat higher in lime than the
Connecticut granites. The magnesia is very low in nearly every
case. The soda, in relation to the potash, is relatively high in some
types and low in others; while one, the red granite of Stony Creek,
proves to be one of the purest potash granites on record. The paper
closes with a general review of the granites of the Atlantic sea board,
which are believed to belong to several different geological periods and
among which the biotite granites largely predominate. W. 0. C.

Contact Metamorphism of a Basic Igneous Rock. By Utysses
SHERMAN GRANT. (Bull. Geol. Soc. Am., 11, 503-510.)

The rock referred to is the Keweenawan gabbro occupying a
roughly crescentic area of about 1,000 square miles in the northeast
corner of Minnesota, between lake Superior and the Canadian bound-
ary. The contact phenomena are described only for the northwestern
border of the gabbro which the author regards as probably intrusive,,
where it lies upon the Archean, Keewatin and, especially the quartzyte,
iron-bearing series, carbonaceous slate and graywacke slate of the Ani-
mikie. The metaporphism is very noticeable, and consists of a partial
or complete recrystallization of the adjacent rocks. Complete recrys-
tallizntiion is the rule near the contact, and in places this extends 500
feet from the contact; while a partial recrystallization is at times no-
ticeable for two or three times this distance from the present margin
of the gabbro. The rather normal metamorphic characters of the slaty
members of the Animikie are first briefly noticed, and then the special-
ly interesting contact phenomena of the iron-bearing series are more
fully decribed. The original rock is regarded as having more or less

52 The American Geologist. Jponars

iron carbonate. This rock has been widely altered by a regional meta-
morphism to a quartz-magnetite-amphibole slate commonly known
as actinolite schist, which has in turn been profoundly changed by the
gabbro, the resuling rock being a coarse-grained aggregate of quartz,
magnetite, olivine or fayalite, hypersthene, augite, hornblende etc.
The derivation of all these minerals, including those like olivine,
augite, and hypersthene, which are characteristic of basic igneous
rocks and rarely found in metamorphosed sediments, from the actin-
olite schist is shown to be possible; and the proofs that this con-
tact zone really belongs to the Animikie and not to the gabbro are
summarized. The contact phenomena of the Keewatin are said to
vary greatly with biotite as a prominent feature. In the Archzan, the
acid rocks or granites have escaped sensible metamorphism, while the
basic rocks or greenstones, including gabbros, diabases and diorytes,
have been profoundly altered, and usually in a way to make them dif-
ficult to distinguish from the gabbro itself. W. 0. C.

Suggestions Regarding the Classification of the Igneous Rocks. By
Wirt1Am H. Hosrs. (Jour. Geol., 8, 1-31.)

After noting the importance of adapting the classification to the
néeds of the field geologist as well as the petrologist, the bearing of
recent petrographical studies on rock classification, the definition of a
rock as an object rather than as an integral part of the earth’s crust,
the importance of texture as a basis of classification, the need of com-
bining chemical and mineralogical classifications as a basis for rock
classification and of substituting quantitative for qualitative analyses,
that rock relationships should be indicated by the combination of
names into a binomial, or, of necessary, a polynomial nomenclature,
the author introduces graphical methods as essential to a comprehen-
sive study of rock analyses. The system of diagrams proposed by
Brégger for this purpose is preferred. In these are set off on radius
vectors the amounts of the eight principal chemical constituents reck-
oned in molecular ratios, ferrous and ferric iron being entered upon
the same radius vector, and silica, because so much in excess of the
others, being evenly divided between the two horizontal radius vectors.
A broken line joining the intercepts on the eight radius vectors forms
a polygon, which may be long and narrow, or short and thick, convex
above or below, or re-entrant in any portion, left or right-handed etc..
according to the chemical constitution of the rock. When viewed in
this diagram the rock comes to have a handwriting by which it may be

instantly recognized; and when drawn to scale the diagram not only

shows the chemical character of the rock but all the results of analysis
may be read from it numerically. The main purpose of this paper is
to adapt the Brégger diagram to represent, not merely an individual
analysis, but a rock species or type covering a considerable range of
differing analyses. In other words, composite diagrams are proposed,
each representing the average of a group of analyses. Examples are
given for the principal types of plutonic and volcanic rocks. The pos-

Ee Se

Review of Recent Geological Literature. ' 53

sibilities of the method are farther illustrated by grouping the dia-
grams in natural series, which show progressive changes in form; and
also by introducing a composite of each series. The numerous an-
alyses upon which the diagrams are based are quoted in tabular form.
W.0: G

The Nomenclature of Feldspathic Granolites. By H. W. Turner.

(Jour. Geol., 8, 105-111.)

Accepting the principle that the classification of granular rocks, if
not of lavas,should be based on mineral composition, the author notes
- that this is equivalent to a classification based on molecular composi-
tion in so far as the minerals are composed each of one kind of mole-
cules. But plagioclase is an exception, since it is compcsed of two
kinds of molecules in ever varying proportions. The author proposes
that the molecular classification be applied throughout; and hence in
calculating the composition of the feldspathic rocks the plagioclase
should be resolved into the constituent albite and anorthite molecules,
and the name plagioclase should not be used. This is shown to be
particularly necessary with the monzonytes and diorytes, which con-
tain both orthoclase and plagioclase, since the plagioclase may vary
from a basic labradorite to an acid oligoclase, thus giving rocks which
could not properly be designated by the same name. It is suggested,
therefore, that if we subdivide the feldspathic rocks on the basis of the
ratio of the alkali-feldspar molecules (Or + Ab)g to the lime feldspar
molecules (An) the true mineral and chemical relations of the rocks
will be brought out and a better classification result. A graphic illus-
tration is given in tables showing percentages of the alkalies and lime
and the ratios of Or ++-Ab to An for the principal feldspathic types. The
author further suggests the use of mineralogical terms in naming
granolytes of simple composition, as orthosyte for a rock composed
chiefly of orthoclase, albityte for one composed chiefly of albite etc.,
the names of other essential constituents to be used in substantive
forms, as quartz-orthosyte or granite, and of accessory constituents in
adjective form, as quartziferous syenyte etc. W. 0. C.

Some Contact Phenomena of the Palisade Diabase. By JoHN DueER
Irvine. (School of Mines Quarterly, 20, 213-223.)

This paper, which, after noting the gradation in texture, density
and mineral composition between the central and peripheral portions
of this great trap sheet, is based chiefly upon the exposures of the upper
and lower contacts afforded by the new tunnel of the New York Sus-
quehanna and Western railroad, confirms in the main the work of An-
drz and Osann, who in 1802 studied the lower contact only, as ex-
posed by the West Shore railroad. The earlier work recognized four
metamorphosis phases of the Triassic shale and sandstone, as follows:
(1) normal hornfels, (2) the same rich in tourmaline, (3) altered ark-
ose containing green hornblende, (4) lime-silicate hornfels. To these
Irving adds five others, three from the lower contact: (1) normal
hornfels rich in spinel, (2) lime-silicate hornfels containing brown

54 The American Geologist. Janne

hornblende. (3) normal hornfels containing “augen” and green horn-
blende; and two from the upper contact: (4, 5) hornfels and arkose
hornfels containing richly scattered crystals of andalusite. Each type
is described in detail; and the evidence is shown to strongly support
the intrusive origin of the diabase, the andalusite and the fact that the
hornstone a hundred feet above the upper contact is baked as hard as
any below the sheet, being especially conclusive in this regard. Another
contact type is believed to be a leucite hornfels, although the analysis
shows it to be too high in alumina and soda and much too low in potash
for a pure leucite; the discrepancy being attributed to interstitial mat-
ter. Leucite has not been previously described as a contact mineral.
W. 0. C.
Ueber grosse tlache Ueberschiebungen in Dillgebiet, voN HERRN E. Kay-
ser in Marburg in Hessen. (Jahrbuch de Konig] preuss, geologi-

schen Landesanstalt for 1900, Bohn, p. 7.)

This article describes the complicated structure of the Devonian and
Culm in the neighborhood of Dill in southern Germany. A complicated
series of upthrow and downthrow of faults is shown by the accompany-
ing map, as cutting all the older formations, but not so much affecting
the Culm though this formation is also cut by them. Several sections
are given to show the details of the action of the force that produced
these movements; and it is also shown that after the faults were pro-
duced a continuation of the movement caused the folding of the bed
affected by the fault—(page 8).

Ueber den nassauischen Culm, von E. Kayser. (Neues Jahrbuch fiir

Mineralogie etc., 1900, Bd. I, p. 132).

In this paper Prof. Kayser refers to the discovery. by Tornqvist in
the Posidononia slate of Hebron of a species of Meek’s North Amer-
ican genus Euchondria (E. europaea Torng.) of which he himself had
found a very perfect example. G. F. M.

Beitrage zur Kenntniss des Siberischen Cambriuwm, I. von EpuarD von
Toit. (Memoires de l’Acad. Imp. des Sciences de St. Petersburg,
viii Ser., vol. viii, No. Io.

This quarto of 57 pages with a number of cuts in the text and eight
plates of figures of the fossils described, is one of the most important
contributions to Cambrian literature that have appeared in the last few
years; not only on account of the thorough treatment of the subject,
but also because of the distant and little known geological field whose
Cambrian fossils are described herein.

Both on the Yenesei, and the Lena the great rivers of Siberia, Cam-
brian deposits are now known to exist, and they supply most interesting
links of association with the contemporary strata on the opposite side of
the world.

Very noticeable is the fulness with which the archeocyathine reef
builders were multiplied in the valley of the Jenesei, and their numerous
species have to a large extent been identified by Baron Toll with Born-
emann’s species in Sardinia.

Review of Recent Geological Literature. - 55

We are startled by the reference of these archaic and puzzling forms
to the calcareous Alge. They have been bandied by various authors
from one class of the animal kingdom to another. Billings, who first
described them, thought they were silicious sponges, and Prof. H. A.
Nicholson and Mr. Walcott supported this opinion. Bornemann who had
an excellent opportunity to study the Sardinian forms, concluded that
they were a special group of Coelenterata. Dr. Hinde who re-studied
the Canadian species concluded that one was a lithistid sponge, and the
rest were to be referred to a distinct family of the Zoantharia-schlero-
dermata. Meek thought Archzocyathus (Ethmopryllum) a true
coral. Sir Wm. Dawson, however, thought two of the Canadian spe-
cies to be Foraminifera.

Baron Toll discusses these conflicting opinions, and having de-
scribed a new genus Rhabdocyathus, comes to the conclusion that
through it he has reached the true solution of the zoological standing
of the Archeocyathine, namely that they are a primitive development
of the calciferous Alge, and are related to the recent Acetabularia and
the Tertiary Acicularia.

Among the material from Siberia Toll claims that he has found
evidence of the embryonic stages of the archzocyathines, and figures
a minute stalked cup with a detachable lid which he conceives to have
been the starting point of an Archzocyathus. In his new genus, Rhab-
docyathus, in which he sees a more primitive archeocyathine than in
the others, the lower part of the tube has separate outer and inner
walls, but in the upper part these walls come together forming a solid
wall; in this genus there are no septz, but the walls are perforate as in ©
the others. Baron Toll regards the connecting tubules that pass from the
inner to the outer wall in the archzocythines as passages for the spores,
which thus escape from the inner cavity. While warmly advocating his
view of the algoid relationship of the Archeocyathine he speaks of it
as a hypothesis, thus inviting criticism of its soundness.

The earlier part of Baron Toll’s work is devoted to a description
of the literature of the Siberian Cambrian, in which he refers to the
earlier work of Dr. F. Schmidt on a more limited collection of Cam-
brian fossils, from some of the localities from which the later collec-
tions came, that have been examined by Toll. Dr. Schmidt had placed
some of these fossils as Devonian, but Toll correctly refers them to
the Cambrian. One of these is a Dorypyge, three others are referred
to the genera Anomocare. Loistracus and Solenopleura (?), (Plate IT).
A pygidium on the same plate referred to Bathyurus howelli, Walc.,
las a wider flattened margin than is common in tliat species.

On plate I are figured a number of new species of trilobites ete.,
from the new localities whose fossils have been studied by Baron Toll.
Two minute species which are referred to Ptychoparia might also
with propriety be compared with the Strenuella type of Agraulos, and
especially with Strenuella attleborensis S and F (Trans. Roy. Soc. Can.,
2 Ser., vol. v, sec. iv., p. 77). An Agnostus of the Loevigati group has
unusual asosciations if occurring in strata with the interesting Micro-

56 The American Geologist. jenna

discus figured on this plate. This greatly resembles the species of this
genus which occur with Olenellus; the Agnostus, however, is flatter
than the typical species of the Paradoxides beds and may be an earlier
form.

In this paper are described, of Ptyhoparia 1 new species, Microdis-
cus 2 new species, Agnostus I new species, Kutorgina (cingulata Bill.)
and Obolella (cf. chromatica Bill.) The species are compared with
those of Europe and America.

Any claim that Agnostrus occurs in strata below Paradoxides re-
quires to be well supported. The type of the one that Ford thought
he found at Troy, N. Y., is lost and the figure he gives scarcely sup-
ports the reference to this genus. Baron Toll thinks that A. atavus oi
Tullberg may be claimed for the Olenellus zone; but while Tullberg
refers the group of strata in which it was found at Andrarum to the
Olenellus zone, Olenellus (i. e. Holmia) is found only in the lower
part of this set of beds, and Tullberg reports a Paradoxides in these
beds below the layer which carries Agnostus atavus.

Descriptions and figures of F. Schmidt’s species are given and a
very fuil account of occurrences of the several forms of the Archzo-
cyathine.

Table C (p.55) is an endeavor to show diagrammatically the chrono-
logical relation of the several parts of the Siberian Cambrian, and the
author’s view of the bearings of the several groupings of species, and
the nature of the sediments, on the probable depth of the Cambrian
sea at the time these creatures of the Cambrian age were entombed.

In conclusion we may congratulate the author on having rescued
from the unknown a new chapter of geological history, and on having
placed us at a new point of view, from which we may regard the ac-
tivities of the Cambrian reef-builders. G. F. M.

La Face de la Terre. (Das Antlits der Erde), par Ep, Susss, traduit
avec l’autorisation de l’auteur et annoté sous la direction de Em-
manuel de Margerie. Tome II, Paris, 1go0.

This well-known classic on the physical features of the surface of
the earth is considerably enlarged by original notes and references to
later literature. This tome begins with the “third part,” the seas. After
a full description of the Atlantic and Pacific ocean, and a comparison
of one with the other, the author enters upon the discussion of paleo-
zoic seas, thus coming within the domain of geology proper. Here is
abstracted and epitomized the result of all the study of the paleozoic
both in America and Europe. The Mesozoic seas are treated in the
same manner, then the Tertiary seas. In chapter VIII the author dis-
cusses the shore lines of Norway, their possible elevation, the glaciers
and fjiords. A history of the temple of Serapis at Pouzzoles, as af-
fected by earth movements, and by volcanic ejection, as well as the
results of exhumation and its present state are included in chapter IX.
The Baltic and the North seas during the historical period, and the
Mediterranean during the same period, are subjects of long inquiry

Review of Recent Geological Literature. airs

and important description. The work closes with a chapter devoted

to the shore lines of the northern seas.

This work thus covers the whole field of modern geology, and
brings within small compass the grand conclusions of the science
on the main features of the history of the stratified rocks. The col-
laborators with M. Margerie, in this translation and in the new ma-
Six and M. Zimmerman. The new French edition of this German
treatise renders a great service to geologists in bringing it within
terial, are Aug. Bernard, Ch. Depéret, W. Kilian, G. Poirault, Ach.
reach of a wider circle of students. The only criticism that may be
made is one that is a common fault of French works, viz: it has no
index, and only the most general subdivisions and running heads. It
is therefore much like a hidden mine which everyone must explore
independently, without guides. English, and especially American,
scientific books are far ahead of those of continental Europe in this
particular. N. H. w.

A Record of the Geology of Texas for the Decade ending December
31, 1806. By F. W. Stmonps. (Transactions of the Texas Acad-
emy of Science, vol. 3, pp. 1-280. Austin, August, 1900.)

This record begins where professor Hill’s Bulletin No. 15 of the
United States Geological Survey leaves off, and covers the decade
which, as remarked in the author’s prefatory note, has been more
fruitful of results than any other and has placed the geology of Texas
upon a solid foundation, notwithstanding the many details that re-
main to be worked out and errors that must be corrected.

It comprises 466 titles, numbered for convenient cross and index-
reference, arranged alphabetically by authors, those of each author be-
ing arranged according to time of publication.

The entry of copious quotations, judiciously selected to show pro-
gressive or important features of most of the papers cited, and the
preparation of brief abstracts of certain papers or parts of papers,
have more than doubled the value of the record as a bibliographic
production. In presenting these Dr. Simonds has been wisely im-
partial, avoiding entanglement in controversial geology and letting the
principal results and contentions of authors speak for themselves.

Lists of fossils, minerals and rocks newly described or illustrated,
or of which new knowledge is added in the papers cited, faunal lists
of formations, condensed geologic sections, chemical analyses and
economic statistics have been freely included.

Thus, in a form compact and convenient for reference, the Record
embodies the best part of the known geology of Texas, and consti-
tutes an admirable handbook of the latter and one that will be indis-
pensable to all future students of the geology of the state or of
North America at large.

Typographical errors do not recur with sufficient frequency to be
burdensome.

An excellent index is provided, embracing topics, localities and
authors. KR. WiC:

58 The American Geologist. January, 1901.

Bulletin of the Hadley laboratory of the University of New Mexico.

Vol. II, part 1, 1900. Published with the cooperation of Mrs. W.

C. Hadley.

This publication embraces several articles, the leading one being
devoted to the geology of the “Albuquerque sheet,’ of the United
States Geological Survey, with the limits of which lies the terri-
torial university. Its authors are C. L. Herrick and D. W. Johnson
It is accompanied by a map and thirty-two plates, mostly of fossils,
of which fourteen are new or undetermined. The article gives a con-
venient synopsis of the geological structure of the area included in
the Albuquerque sheet, with incidental references to the surrounding
country. The Tertiary forms a large central triangular mesa, extend-
ing from the Rio Grande to the Puerco, with a gentle general dip to
the southeast. Volcanic rocks forming cones and flows pierce and lie
upon the Tertiary, the most notable being the volcanoes a short dis-
tance west from Albuquerque. These are believed to be a part of a
series that runs north and south, indicating a line of weakness and
perhaps of fracture and faulting. It is interesting to note that some
specimens of maize embraced in what was supposed to be a part of
this lava were traced to a recent artificial origin, the “lava” being simply
fused adobe, a part of an abandoned brick kiln. Thus the idea that
man was contemporary with the lava was abandoned.

The Sandia mesa rises from the Rio Grande toward the east. The
inclination is much increased near the Sandia range of hills a spur
from which enters the area of the sheet. These hills are due to a great
fault which has brought to the surface the Permian and Carboniferous
the uplift being on the east side of the fault. This dynamic movement
was accompanied by metamorphism and apparently by fusion of the
rocks concerned, giving vent to granite.

In the Cretaceous of the western part of the area are lignite beds
which have been considered Laramie but they lie below the Fox
Hills of the Cretaceous. Some pre-Tertiary igneous rocks that pierced
the Cretaceous and modified its beds, are found near the Puerco val-
ley, west of Albuquerque, in the form of isolated trachyte cones, the
surface lavas of which had apparently been eroded and lost prior to
the Tertiary covering which has since been also removed by the
erosion incident to the Puerco valley. The authors gave the petro-
graphic characters of these rocks and of the Tertiary basalt.

Short paragraphs are devoted to the building materials, and es-
pecially the clays, and to irrigation.

Pres. Herrick also discusses in a short article the possibilities of
salt, gypsum, cement, clay and graphite, in New Mexico.

The volume also contains ‘Report on a geological reconnoissance
in western Socorro and Valencia counties, New Mexico,’ and “Identi-
fication of an Ohio Coal Measures horizon in New Mexico.” which
have appeared in the American Geologist; also “The Geology of the
White Sands of New Mexico,” from the Journal of Geology, and
closes with “The Cyanide process in New Mexico” by V. V. Clark.

‘= ene? Leia
aren iy,
1's |

Author's Catalogue. 59

The publication indicates great activity and energy on the part of
Dr. Herrick, who has produced this and the preceding bulletin in ad-
dition to his duties as president of the Territorial University. Such
a publication must be one of much convenience and value to the people
of the territory. N. H. W.

The Geology of Eastern Berkshire County, Massachusetis, B. K.
Emerson. (Bull. 159, U. S. G. S.)

This bulletin is supplementary to the Housatonic folio, and treats
of the area adjoining the Green mountain and Hoosac mountain re-
gions, which have been the subjects of recent monographs.* The bul-
letin consists principally of lithological and petrographical descriptions.

The region described represents the central portion of a deeply
eroded mountain region. It presents a complicated series of much
folded and faulted pre-Cambrian and early Paleozoic rocks. Mr. Emer-
son distinguishes and describes six gneisses, three limestones, three
schists and one quartzyte. He concludes with a lexicon of Berkshire
county minerals.

The bulletin is somewhat fragmentary. It does not give a complete
history of the region nor discuss any of the larger problems involved.
Doubtless the Housatonic folio will treat of this side of the subject
and as an appendix to the folio the bulletin will be of value. 1. H. 0.

MONTHLY AUTHOR’S CATALOGUE

OF AMERICAN GEOLOGICAL LITERATURE
ARRANGED ALPHABETICALLY.

Bather, F. A. .

Pores in the Ventral sac of Fistulate Crinoids. (Am. Geol., vol.
26, pp. 307-312, Nov., 1900.)

Bennett, L. F.

Notes on the eastern escarpment of the Knobstone formation in
Indiana. (Proc. Ind. Acad. Sci., 1808, pp. 283-288, Indianapolis, 1890.)
Bennett, L. F. ,

Headwaters of Salt creek, in Porter county. (Proc. Ind. Acad.
Sci., 1899, pp. 164-166, Indianapolis, 1900.)

Clarke, J. M.

Report of the state paleontologist (New York), 1809. (53rd Rep.
N. Y. State Mus., pp. 659-816. Albany, 1900.)

Clarke, J. M.

A remarkable occurrence of Orthoceras in the Oneota beds of the
Chenango valley, N. Y. (Bull, No. 30, vol. 8, N. Y. tate Mus., pp. 167-

170, plates 1-4, Oct., 1900. )

*Geology of the Green Mts. in Massachusetts, by Pumpelly, Wolff, Dale.
Mon.) U.S. G: - Si: <OKIT.

60 The American Geologist. January ia

Clarke, J. M.

Paropsonema cryptophya; a peculiar echinoderm froin the Intu-. ~

mescens zone (Portage beds) of western New York. (Bull. No. 39,
vol. 8, N. Y. State Mus., pp. 172-186, plates 5-9, Oct., 1g00.)
Clarke, J. M.

Dictyonine hexactinelid sponges from the upper Devonic of New
York. (Bul. No. 39, vol. 8, N. Y. State Mus., pp. 187-195, pp. 10 and
11, Oct., 1900.)

Clarke, J. M.

The water biscuit of Squaw island, Canandaigua lake, N. Y. (Bull.
No. 39, vol. 8, N. Y. State Mus., pp. 195-108. pls. 12-15, Oct., 1900.)
Clarke, J. M.

Note on the Siluro-Devonic boundary. (Reprint from Science, N.
S. vol. 12, pp. 406-408, Sept. 14, 1900.)

Clarke, J. M.

The Oriskany fauna of Becraft mountain, Columbia county, N. Y.
(Mem. N. Y. State Mus., No. 3, vol. 3, Oct., 1900, pp. 1-128, pls. 1-9.)
Culbertson, Glenn.

The weathering and erosion of north and south slopes. (Proc. Ind.
Acad. Sci., 1899, pp. 167-170, Indianapolis, 1900.)

Cumings, E. R.

On the Waldron fauna at Tarr Hole, Ind. (Proc. Ind. Acad. Sci.,
1899, pp. 174-176, Indianapolis, 1900.)

Cumings, E. R.

The stream gradients of the lower Mohawk valley. (Proc. Ind.
Acad. Sci., 1899, Indianapolis, 1900.)

Dall. W. H.

Contributions to the Tertiary Fauna of Florida, with special refer-
ence to the silex beds of Tampa and the Pliocene beds of the Caloo-
sahatchie river, including in many cases a complete revision of the
generic groups treated of and their American Tertiary species. (Trans.
Wag. Free Inst., vol. 3, part 5, plates 36-47, Dec., 1900.)

Dennis, D. W.

2 =: old shoreline. (Proc. Ind. Acad. Sci., 1898, p. 288, Indianapolis,
1890.
Dennis, D. W.

Two cases of variation of species with horizon. (Proc. Ind. Acad.
Sci., 1898, p. 288. Indianapolis, 1899.)
Douglas, E.

New species of Merycochoerus in Montana. (Am. Jour. Sci., vol.
10, pp. 428-438, Dec., 1900.)

Dowling, D. B.

General index to the reports of progress, 1863-1884. Geol. Sur.
Can., pp. 475. Ottawa, 1900.

Dryer, C. R.

Old Vernon; a geographical blunder. (Proc. Ind. Acad. Sci., p.
273, 1898. Indianapolis, 1899.)

Dryer, C. R.-

The meanders of the Muscatatuck at Vernon, Indiana. (Proc. Ind.
Acad. Sci., 1898, pp. 270-273. Indianapolis, 1899.)

Author's Catalogue. OI

Dryer, C. R.

Ne rock. (Proc. Ind. Acad. Sci., 1898, pp. 268-269. Indianapolis,
1899.

Elrod, M. M.

The Geologic relations of some St. Louis group Caves and Sink-
holes. (Proc. Ind. Acad. Sci., 1808, pp. 258-267. Indianapolis, 1899.)

Emerson, B. K.
Some curious facts illustrative of geological phenomena. (Am.

Geol., vol. 26, pp. 312-315, plates 21 and 22, Nov., 1900.)

Hatcher, J. B.

The vertebral formula of Diplocodus (Marsh). (Science, N. S.,
vol. 12, p. 828, Nov. 23, 1900.)
Herrick, C. L. (and D. W. Johnson.)

The geology of the Albuquerque sheet. (Bull. Sci. Lab. Den. Univ.,
vol. II, pp. 175-239, pls. 27-58, map, June, 1900.)
Flilder, F. F.

Gold in the Philippines. (Nat. Geog. Mag., vol. 11, pp. 465-470.)

Johnson, D. W. (GC. L. Herrick and)

The geology of the Albuquerque sheet (Bull. Sci. Lab. Den. Uniy.,
vol. II, pp. 175-238, pls. 27-58, map, June, 1900.)

Keyes, C. R.

Certain Faunal aspects of the original Kinderhook. (Am. Geol.,
vol. 26, pp. 315-322, Nov., 1900.)

Knight, W. C.

The Wyoming fossil fields expedition of July, 1899. (Nat. Geog.
Mag., vol. 11, pp. 449-465, 7 plates, Dec., 1900.)

Koenig, G. A.°

Mohawkite, Stibiodomeykite, Domeykite, Algodonite, and some ar-
ay copper-arsenites. (Am. Jour. Sci., vol. 10, pp. 439-448, Dec.,
1900.

Kunz, Geo. F.

The. production of Precious stones in the United States in 1890.
(21st Am. Rep., U. S. G. S., 1899-1900, Part VI, pp. 1-48.)

Loomis, Fred B.

Siluric fungi from western New York. (Bull. No. 39, vol. 8, N. Y.
State Mus., pp. 223-226, plate 16, Oct., 1900.)

Hord, Ea C. E.

Notes on the Geology and Petrography of Monhegan island, Maine.
(Am. Geol., vol. 26, pp. 329-348, plate 22, Dec., 1900.)

Matthew, G. F.

New species of Cambrian fossils from Cape Breton. (Bull. Nat.
Hist. Soc., New Brunswick, vol. iv, p. 219, St. John, 1900.)
Middleton. W. G. (and Joseph Moore.)

Skull of fossil bison. Proc. Ind. Acad. Sci., 1899, pp. 178-181, 1900.

Montgomery, H. F,

The Kenkakee valley. (Proc. Ind. Acad. Sci., 1808, pp. 277-282.
Indianapolis, 1899.)

‘

62 The American Geologist. Janugry, 2001.

Moore, Joseph (W. G. Middleton and)

Skull of fossil bison. Proc. Ind. Acad. Sci., 1890, pp. 178-181. In-
dianapolis, 1890.)
Moore, Joseph.

A cranium of Castoroides found at Greenfield, Indiana. (Proc. Ind.
Acad. Sci., 1899, pp. 171-173. Indianapolis, 1900.)
McBeth, Wm. A.

The Physical Geography of the region of the Great Bend of the
Wabash. (Proc. Ind. Acad. Sci., 1890, pp. 157-161. Indianapolis, 1900.)

McBeth, Wm. A.

An interesting boulder. (Proc. Ind. Acad. Sci., 1899, p. 162. In-
dianapolis, 1900.)

McEvoy, James.

Report on the Geology and natural resources of the country trav-
ersed by the Yellow Head Pass route from Emonton to Téte Jaune
Cache, comprising portions of Alberta and British Columbia. Geol. Sur.
Canada, Part D, An. Rep., vol. 11, pp. 44. map, Ottawa, 1900.

Newsom, J. F. (and J. A. Price.)

Notes on the Distribution of the Knobstone Group in Indiana.
(Proc. Ind. Acad. Sci., 1898, pp. 289-291. Indianapolis, 1809.)

Osborn, H. F.

Correlation between Tertiary mammal horizons of Europe and
America, parts I and 2. (Annals N. Y Acad. Sci., vol, 13, pp. 1-72,
July 18, 1900.)

Perkins, Geo. H.

Report of the state geologist on the mineral resources of Vermont,
1899-1900, pp. 83, plates. Burlington, 1900.

Rand, Theo. D.

Notes on the Geology of southeastern Pennsylvania. (Proc. Acad.
Nat. Sci., Philada., Feb., 1900, pp. 159-338.)

Sardeson, F. W. 5

Meteorology of the Ordovician. (Am. Geol. vol. 26, pp. 388-391,
Dec., 1900.)

Scovell, J. T.

Terraces on the lower Wabash. ( Proc. Ind. Acad. Sci., 1898, pp.
274-277. Indianapolis, 1899.)

Simpson, Geo. B.

Preliminary descriptions of new genera of paleozoic rugose corals.
(Bull. No. 39, vol. 8, N. Y. State Mus., pp. 199-222, figs. 1-45, Oct.,
1900. )

Sollas, W. J.

Evolutional geology. II. (Science, N. S., vol. 12, pp. 787-796, Nov.
22, 1900. ) ;
Turner, H. W.

The Pleistocene Geology of the South Central Sierra Nevada with
special reference to the origin of the Yosemite valley. (Proc. Cal.
Acad. Sci., 3rd Ser., vol. 1, No. 9, pp. 261-320, pls. 31-39. Dec. 1, 1900.)

Personal and Scientific News. 63

‘

Vaughan, T. W.

A Tertiary coral reef near Bainbridge, Georgia. (Science, N. S.,
vol. 12, p. 873, Dec. 7, 1900.)

Weeks, Fred B.

Bibliography and Index of North American Geology, Paleontology,
Petrology and Mineralogy, for the year 1899. Bull. No. 172, U. S.G. S.
1900.

Whiteaves, J. F.

On some additional or imperfectly understood fossils from the
Cretaceous rocks of the Queen Charlotte islands, with a revised list of
species from those rocks. (Geol. Sur. Can., Mesozoic Fossils, vol. 1,
Part IV, pp. 263-307, pls. 33-39, Nov., 1900.)

Winchell, Alex. N.

Mineralogical and Petrographic study of the Gabroid rocks of

Minnesota. and more particularly of the Plagioclasytes, III. IV. (Am.

Geol., vol. 26, pp. 261-307, Nov., 1900; ditto, Am. Geol., vol. 26, pp.
348-388, Dec., 1900.)

PERSONAL AND SCIENTIFIC NEWS.

THE FAMOUS CLARENCE S. BEMENT COLLECTION OF MIN-
ERALS which has attracted mineralogists from all over the
world to Philadelphia for so many years, when they wished to
see some of the finest specimens known, has been purchased by
the friends of the American Museum of Natural History and
has been presented to that institution. The donors’ names
are withheld from the public at present, though this is the
largest and most valuable single gift ever made to the museum.
The minerals in the collection are said on good authority to
have cost Mr. Bement not less than $150,000, while the meteor-
ites contained in it are said to have cost an additional $50,000.
This great acquisition places the mineral collection of the
North American Museum on a footing comparable with that
of the greatest collections in Europe, and the meteorite collec-
tion is probably surpassed only by those at the British Museum
and the Royal Museum at Vienna. ‘The collection arrived at
the museum during the last week of the old year, has been
unpacked and its installation is proceeding’ as rapidly as possi-
ble. The old museum collection has been relegated to drawers
for the present, but eventually the two are to be consolidated.

Pror. Henry FAirCHILD Osporn has resigned his position
as assistant to the president of the American Museum of Nat-
ural History, in order to have time to attend to his new duties
as vertebrate paleontologist to the United States Geological
Survey. He retains, however, the curatorship of the depart-
ment of vertebrate paleontology in the museum, and will con-
tinue as heretofore the building up of the collection the assem-

64 The American Geologist. Janteese teas

bling of which has been under his direction for the past ten
or eleven years.

Pror. H. C. Bumpus, or Brown University, has been
called to the position in the American Museum left vacant by
Prof. Osborn, and he assumed office as “assistant to the
president” on the Ist of January. Recent invertebrates have
been taken away from the department of geology and reptiles
and fishes from the department of vertebrate zoology and
erected into a new department, of which Prof. Bumpus has
been made curator.

The old department of geology has been further subdivided
by constituting a new department of mineralogy, of which
Mr. L. P. Gratacap has been made curator. Mr. Gratacap
also retains charge of the recent shells, of which he has had
the care for several years. Prof. R. P. Whitfield remains cur-
ator of the reorganized department of geology and inverte-
brate paleontology, which these changes restore to the scope
which it had when he came to the museum more than twenty-
three years ago. Dr. E. O. Hovey, who has been assistant
curator in the department for seven years, has been advanced
to be associate curator.

GEOLOGICAL Society oF WasHINGTON.—The following
was the program for the meeting on January oth: N. H. Dar-
ton, ‘“Comparison of the Geology of the Black Hills with that
of the Front Ranges of the Rocky Mountains ;” A. H. Brooks
and A. J. Collier, “Glacial Phenomena in the Seward Penin-
sula, Alaska ;” A. C. Spencer, ‘““The Physiography of the Cop-
per River Basin, Alaska.”

A skerou oF Dr. Lucius Ler Hussarn, former state geol- _
ogist of Michigan, is given in the Michigan Miner, vol. 3, No.
1, Dec. 1, 1900. The sketch is accompanied by a photograph
and was written by Dr. Alfred C. Lane, the present state geol-
ogist.

A new “Geological Review” has been established in Ger-
many, edited by Dr. K. Keilhack, at Berlin, published by
Borntraeger Brothers, at Leipzig. The first number is dated
Jan. 1, 1901, has thirty-two pages and embraces reviews of
geological contributions from all parts of the world, printed in
German, French and English. The American co-editors are
F. D. Adams, H. M. Ami, W. H. Beal, E. Bose, W. M. Davis,
F. P. Gulliver, Eugene Hussak, F. H. Knowlton, H. B. Kiim-
mel, C. Palache, H. Ries, R. D. Salisbury, T. W. Stanton, and
J. E. Wolff. There are sixty-three other co-editors. G. E.
Stechert, New York, agent. Subscription, 30 marks.

Tue DEPARTMENT OF GEOLOGY AND GEOGRAPHY AT Har-
vARD UNIVERSITY will move at the en dof this college year into
the new wing of the University Museum, now being con-
structed for its use. This will relieve it from the cramped
quarters which it has occupied for so long.

Personal and Scientific News. 65

On Nov. 16 and 17 a party of Harvard students and in-
structors returned the visit of their Yale fellow workers. Fri-
day afternoon was spent in visiting the museums in New
Haven, the evening in social and scientific conference, and Sat-
urday was given to trips to regions of geological interest near.

The first year men in research, in the Division of Geology
at Harvard University are engaged in a very detailed survey
of the Middlesex Falls, under the guidance of Dr. T. A. Jag-
‘ger, Jr. This is on a larger scale than heretofore ever attempted.
The contour map of the Metropolitan Park Commission is
used as a basis. The area of survey is to be gradually extended.

Proressor J. W. Grecory, of MELBOURNE, AUSTRALIA,
passed through the country in November, on his way to Lon-
don to arange for a boat for the British Antarctic epedition,
which is to start next summer. He made short stops at Chi-
cago and at Cambridge, to meet the geologists there and look
over their equipment.

GEOLOGICAL SociIETY OF WASHINGTON. The annual meet-
ing for the election of officers was held on December 19th. At
this meeting Mr. Whitman Cross gave the presidential ad-
dress on “The Development of Systematic Petrography in the
Nineteenth Century.” At the meeting of December 12th the
following program was presented:

4 2 W. Hayes :—Geological relations of the Tennessee brown phos-
ate.
‘ Lester F. Ward :—The autochthonous or allochthonous origin of the
coal and coal plants of central France.
“ E. Howell :—Exhibition of a geologic relief map of the United
ates.

THE PETROGRAPHICAL REFERENCE COLLECTION of the U.
S. Geological Survey at present numbers over 1,000 specimens,
with complete card indices, and is now available for the use of
petrographers. It is hoped soon to issue a descriptive circular
for the information of all to whom such a collection may be of
value. One of the features of this collection is the valuable
series of the igneous rocks of the Christiania region which
Prof. W. C. Brégger brought to this country when he came
last spring to deliver the George Huntington Williams memo-
rial lectures at Johns Hopkins University.

MoTHER Lope District, CALIFORNIA. The United States
Geological Survey has recently published Folio No. 63 of the
Geological Atlas of the United States designated the ‘‘Mother
Lode Survey District Folio, California.”

The folio comprises two sheets of topographic maps, on
the scale of one mile to the inch (1-63, 360), embracing an
area six and one-quarter miles wide and about seventy miles
long, two sheets showing the relation of the mining claims to
topography and geology, two sheets illustrating the areal and
economic geology, and two sheets of structure sections.

66 The American Geologist. Janne aaa

In the eleven pages of descriptive text, signed by F. L.
Ransome, geologist, there is presented a concise and simple
statement of the general geological features of the district.
The history of the events which led up to the present geolog-
ical, economic, and topographic relations is also briefly told.

The gold-quartz veins, which give to this region its chief
importance, are discussed with reference to origin, structure,
and relations to the inclosing rocks. This general account of
the auriferous lodes is followed by brief notes on the prom-
inent mines. The resources of the district, other than gold,
are treated at lengths proportionate to their relative impor-
tance. The more important results derived from the investi-
gation of the district, especially those which may be of value
in its future economic development, are finally gathered to-
gether in a terse summary.

THRE WASHINGTON ACADEMY OF SCIENCES is preparng a
new directory of the membership of the Academy and of its
nine affiliated societies. This will conform in general character
to the directories of the scientific societies of Washington, D. C.
heretofore published.

Mr. T. C. WEsTON has written and published a volume giv-
ing reminiscences of his thirty-five years connection with the
Geological Survey of Canada, which began in 1859 and ended
in 1894. These pages recall men who have been noted in Can-
adian geology—Logan, Hunt, Billings, Richardson, Barlow,
Murray and others.

THE CoLLEecTION OF Duparc’s GREAT RELIEF MopEts of
structures of the Alps includes one that shows the Glarner
double fold according to A. Heim. Others illustrate vividly
symmetrical and unsymmetrical anticlinal folds ; inverted arch-
es and anticlinal folds and other interesting mountain struc-
tures. ~This collection of eight models in plaster of Paris was
displayed at the Swiss naffonal exhibition at Geneva, in 1896.
It is one of the most important series available for museums
or lecture-rooms. The cost is $100.

GRANITE MoNovLiTHs are being quarried at Vinal Haven,
Maine, for the cathedral being built at Morning side Park, New
York. Thirty-two of these columns are required to be 54 feet
long and 6 feet in diameter, each weighing 160 tons, or two-
thirds as much as Cleopatra’s needle in Central Park. For
dressing and polishing these granite columns they are mounted
in a giant lathe and revolved so as to bring their exterior sur-
face first against cutting tools and afterward on polishing ma-
terials. This lathe is 86 feet long and weighs 135 tons, and the
rough stone which it reduces to dimension, weighs at first as
much as 310 tons. This lathe was designed and patented by
engineers of Boston, and was constructed in Philadelphia.—
(Sct. Am.)

est
ee

x mn
Pa)

fe a

LIBRARY

OF THE
UNIVERSITY of ILLINOIS,

THE AMERICAN GEOLOGIST. VOL. XXVII. PRATE lk.

Fig. 1. VIEW IN THE GORGE, SHOWING THE JOINT
STRUCTURE OF THE SCHIST.

Poet AN GEOLOGIST:

Vor. XXVII. FEBRUARY, 1go1. Nez, 2:

THE GEOLOGY OF THE TALLULAH GORGE.
By S. P. Jonges, Vanderbilt University, Nashville, Tenn.
PLATES IX-XI.

Introductory and general description.

In papers of a physiographic nature the Tallulah gorge in
northeastern Georgia has been incidentally mentioned by dif-
ferent writers a number of times.

Nothing on it per se, however, has ever appeared, with
the exception of an article of a rather general character by
Dr. W. L. Jones, formerly professor of geology at the Uni-
versity of Georgia, published in the Atlanta Journal about
1892.

An opportunity was afforded the writer during the past
summer to examine the region in detail, and the following
paper is offered as a small contribution to the geology of
Georgia.

The Tallulah river rises in western North Carolina just
above the Georgia line, flows in a southeasterly direction
through Rabun county in the extreme northeast corner of
Georgia and, uniting with the Chattooga at the South Caro-
lina line, forms the Tugaloo, a tributary of the Savannah.

Its entire course is within the Blue Ridge mountains, the
easternmost of the southern Appalachians, its flow being down
the southeastern slope and approximately at right angles to
the axis of the range.

By reference to the accompanying topographic map (Plate
X.) it will be seen that all the streams in the region under
consideration have dissected deep valleys, while the more~

68 The American Geologist. February, 1901.

prominent peaks and ridges exhibit a close correspondence in
altitude along a northeast southwest direction, with a fairly
uniform increase in hight from the southeastern foothills to
the crest of the range. It will also be noticed that the head
waters of Panther creek, which empties in the Tugaloo a few
miles below the mouth of the Tallulah, and those of Glade
creek, a tributary of the Chattahoochee, are within less than
a mile of each other with a low divide between them.

The investigations of geologists most familiar with the
southern Appalachians have shown that the greater portion,
if not all, of the province has been twice base-leveled—once
during Cretaceous and once during Tertiary times.*

In the region around Tallulah falls, however, considerable
areas seem not to have been reduced to base level and, owing
to close proximity in altitude and other complicating condi-
tions, the differentiation of the two peneplains in northeastern
Georgia is not easy.

For the last four miles above its confluence with the Chat-
tooga the Tallulah river cuts through the southeastern side
of a series of broken ridges called the Tallulah mountains and
it is here that the gorge and falls of the same name are lo-
cated.

In the region of the gorge the river has a normal flow, as
determined by Mr. B. M. Hall, hydrographer for the U. S.
Geological Survey, of about 180 cubic feet per second.

The town of Tallulah Falls is on the western side of the
river three miles above its mouth and an iron bridge, con-
venient in locating positions, spans the gorge on the road
to Clayton, Georgia.

The gorge begins about a mile and a half above this bridge
and runs all the way to the mouth of the river. From here
it may be considered as being continued by the Tugaloo for
about two miles.

Above the gorge the Tallulah presents the usual character-
istics of a rapid flowing mountain stream with steep slopes
on either side and sufficient valley land at places to afford
small farm settlements. Below the gorge the Tugaloo pre-
sents a similar aspect characterized, however, by broader al-

*C, W. Hayes, and M. R. CAMPBELL, Geomorphology of the Southern Ap-
palachians. National Geographic Magazine. 1894, vol. vi, p. 63-126

THE AMERICAN GEOLOGIST, VOL. X XVII, PLATE =<;

S09 my - <7 ot) 500 BEET
“tee Agi Sg ase CONTOURS

TOPOGRAPHICAL MAP OF THE REGION OF THE:
TALLULAH RIVER.

a
AV (a
yt im &

The Geology of the Tallulah Gorge.—Jones. 69

luvial borders and a more rounded contour of adjacent hills
as it approaches the Piedmont plain.

The falls occur in a section of the gorge three-fourths
of a mile long beginning half a mile below the bridge. Named
in succession, they are: L’Eau d’Or, Tempesta, Hurricane,
Oceana and Bridal Veil. None has a vertical fall of over

- ninety feet, though the total descent of the river from the

first to the last fall is about 360 feet.

At the Indian Arrow rapids, just above the falls, the river
is a hundred feet below the principal street of the town, some-
what arbitrarily assumed as the level of the upper edge of the
gorge at this point. From here the gorge deepens and widens
rapidly, reaching its greatest depth in the neighborhood of the
horseshoe bend in the portion below the falls termed the
“Grand Chasm. Here the gorge is 530 feet deep as measured
from the roadbed of the Northeastern Georgia R. R., which
runs for a short distance along the brink of the chasm. Rei-
erence to the accompanying map and profile (Plate XI.) of a
portion of the river will bring out these points more clearly.

From the Grand chasm to the junction of the two rivers
the gorge is somewhat shallower and with less definitely de-
fined walls than in the region just described, some strips of
cultivated land bordering each side of the river near its lower
end. It is in the region of the falls and Grand chasm that
the typical gorge character is best developed and it was doubt-
less the wild, rugged scenery of this portion that suggested
the Indian name “Tallulah” or “the terrible.”

Geological Features.

Tallulah falls is situated within the region designated on
any geological map of Georgia as the “Crystalline Area.”

This formation embraces all the northeastern portion of
the state and is made up principally of granites, gneisses and
crystalline schists.

The exact position of these rocks in the geological time
scale has never been determined. They are generally classed
as pre-Cambrian.

In the small geological map accompanying this article
(fig. I.) three areas are shown—a quartz schist formation,
a narrow belt of limestone and a biotite schist on either side

70 The American Geologist. Hepruary, Aas

of the limestone. The first merits special description, the
gorge being confined to it.

1777]
2 Ss
3 (0

1Mile

Fic. 1. 1 Quartz schist; 2 Biotite schist; 3 Limestone; A Tallulah river; B
Chattooga river; C Tugaloo river; D Panther’s creek.

This quartz schist, as far as mapped, exhibits an unusually
well developed joint structure one of whose planes corre-
sponds closely with the schistosity dip which is about 25° in
a direction south 20° west.

If this schist was derived from pre-existing sedimentary
rocks, as seems probable, the strike of the true bedding planes,
which have since been obliterated in the perhaps several times
repeated metamorphism of the region, must have corre-
sponded with that of the limestone belt which, as can be seen
from the map, makes a large angle with the schistosity strike.

The course of the Tallulah, and indeed of all the streams
in the region under consideration, seems to show no evidence
of close adjustment between the flow of the rivers and the dip
and strike of the rocks.

Figures I and 2, plate [X. show very well the joint struc-
ture mentioned above and the relation of the river to the
rock.

aie Geology of the Tallulah Gorge.—Jones. ere

Megascopically the schist is a gray, medium grained, com-
pact rock and exceedingly hard under the hammer. The
schistose structure is not conspicuous in unaltered specimens,
but shows plainly wherever weathering has taken place. Ir-
regularly distributed masses of pyrite are quite abundant and
on all exposed surfaces the iron oxide stain resulting from

_their decomposition is characteristic.

Under the microscope the rock is seen to be composed
principally of quartz; this material probably amounting to
go° of the whole. Feldspars are next in abundance, muscovite
probably next, pyrite, some biotite, occasional grains of mag-
netite, small crystals of apatite and a few isolated masses of
some irregularly shaped, highly refractive substance show-
ing low double refraction and giving no very satisfactory in-
dications as to its nature.

The quartzes are in the form of irregularly shaped grains

closely interlocked, many showing wavy extinction and all

more or less shattered, with the cracks filled with subse-
quently deposited silica. Nothing in the nature of a zonal
structure or anything indicating original sedimentary mate-
rial is to be found, but owing to the evident crushing and
metamorphism that has taken place this can only be regarded
as negative evidence with reference to such a possible origin.

Of the feldspars, microline and plagioclase are the most
abundant with some perthitic intergrowths of orthoclase and
plagioclase. Much of the feldspar is broken and cracked like
the quartz, but not to so great an extent.

Some of the muscovite has undergone alteration and is ac-
companied by granular epidote.

The biotite is frequently accompanied by sheaf-like masses
of minute needle-like crystals showing very high interference
colors—doubtless rutile. A chemical determination of the
amount of silica present would enable the rock to be classified
with greater certainty.

At several points along the gorge thin seams or lenticular
masses of intercalated, highly graphitic margarite schist
carrying crystals of tourmaline are noticeable.

The limestone and biotite schist may have possibly had
some influence in determining former drainage, but present
no special features for present consideration.

72 The American Geologist. February, 1901.

Origin of the Falls and Gorge.

Detailed examination of the gorge and river with related
topographic features brings out clearly two important facts
—lIst, that the gorge has been produced entirely by the erosive
action of the river, assisted by atmospheric agencies, and, 2nd,
that both the falls and gorge are, geologically speaking, of
very recent age.

Evidences of marked stream erosion are everywhere vis-
ible along the margin of the river in the upper part of the
gorge. At the Indian Arrow rapids, above the falls, the river
has, by deflection and concentration of its flow, on the left
bank exposed on the west side a considerable portion of bed
rock, now a yard or more above normal water level. An in-
structive display of pot-holes is to be seen here in the hard,
polished rock, some of them four or five feet in diameter and
deeper than broad. A little farther down stream on the right
bank a large pot-hole can be found about two yards above
water-level, partially filled with decayed rock and vegetable
mould and having in it the stump of a tree five or six inches
in diameter. The absence of similar evidences of stream ac-
tion along higher levels is to be noted and is due to the widen-
ing of the gorge that has taken place through atmospheric
agencies. The well developed joint structure of the schist
has greatly facilitated the rapid action of these agencies in a
climate where alternate freezing and thawing is frequent dur-
ing the winter season, and the tumbling in of large blocks has
produced a recession of the walls of the gorge probably pari
passu with the down cutting of the stream. Also the rock,
though of a hard flint-like texture, weathers rapidly in the
moist air of the gorge, the decomposition of the pyrite and
feldspars allowing the quartz grains to fall apart. The
greater width of the lower portion of the gorge bears testi-
mony to its greater age and the longer continued action of
these forces. The comparative youth of the gorge is indi-
cated by the steep grade of the river and the presence and
character of the falls as well as by the steepness of the walls.

The immediate location of the falls is not a permanent one,
but they are constantly working up stream at a rate that may
be rapid enough to admit of measurement, though inquiries

TH PLATE Xl.

Hurrz Cane

2 /740 JZ 3S | 672
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= XN!
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I

MAP AND PROFSUE “OF TALLULAH RIVER
FROM HEAD OF GORGE TO GRAND C>mM

| \ ors Hotel Robinson REDUCED FROM MAP AND PROFILE
AY . By

ifr

B.M.HALL, HYDRIOGRAPHER, U.S. GEO. SURVEY

THE AMERICAN GEOLOGIST, VOL. X XVII.

PROFILE OF RIVER )

measurements in deet prom
A Xo “H* and )rom river te
"LINE LEVEL’, vertieal
seale exayrerated

Hurricane

upe PLATE XI,
LIVE LEVEL with A
TESS ee = ——_ eS —
3 &. 175¢ if Le sr VL | 1740 v 1333 |, 670
H : 1
' i
SI 1
=
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MAP AND PROF/LE OF TALLULAH RIVER
FROM HEAD OF GORGE TO GRAND CSM

REDUCED FROM MAP AND PROFILE
BY,
B.M.HALL, HYDRIOGRAPHER, U.S. GEO. SURVEY

oa
Pgs Robinson

The Geology of the Tallulah Gorge.

Jones. 73

among the old inhabitants of the neighborhood failed to throw
any light on this point. There is nothing, however, to indi-
cate that they have migrated from a definite, initial position
as in the case of a fall like Niagara working back by under-
mining. Indeed, the presence of a number of sloping falls
(they are all more or less sloping) instead of a single vertical
one would preclude the idea of any such origin. They are
~ rather to be looked upon as rapids or shoals of an accentuated
type where the grade of the river is steepest in its course to
the lower level of the Tugaloo.

Mr. C. W. Hayes thinks that the Chattooga river and the
tributary Tallulah have been captured and diverted from the
Chattahoochee to the Savannah drainage system by the Tug-
aloo and that the falls on the Tallulah show that the Tugaloo
has not yet had time to subdue the recently acquired terri-
tory.* Mr. M. R. Campbell has also advanced views of a
similar nature.t

As both these writers consider a case of stream piracy to
have taken place here, the origin of the gorge will first be con-
sidered on such a supposition.

From the top of any prominent peak east of Tallulah
river in the region of the gorge a long even-crested ridge, the
Chattooga ridge, can be seen on the southeastern side of
the Chattooga. A natural continuation of this is seen west
of the Tallulah in the region of Panther creek, while a deep
gap, through which a broad vista of the low country is ob-
tained, marks the position of the Tugaloo. If a capture took
place it was probably at a point a short distance above the
mouth of Panther creek; the Chattooga originally continuing
its course to the Chattahoochee along the valley of Panther
creek and its west fork, the present reversed drainage of this
creek being necessarily brought about by the lower grade of
the Tugaloo. The divide between the western fork of this
creek and several creeks tributary to the Chattahoochee is at
its lowest point between 300 and 400 feet above the present
level of the Tugaloo at the juncture of the three streams, and
Chattooga.

*C.W Haves. The Southern Appalachians, Monograph, National Geogra-
phie Society, 1896, vol. i, p. 327.

7M. R. CAMPBELL. Drainage modifications and their interpretations.
Tournal of Geology, 1896, 4, 657-678.

74 The American Geologist. Mebron ray) aaa

While there is no way to measure the erosion that has
taken place at this point since the supposed capture, nor the
relative rapidity of the lowering of the land here, as compared
with the lowering of the bed of the Tugaloo, yet as it is now
the divide between the two creeks and is undergoing consid-
erable erosion, it is not unreasonable ‘to suppose that at the
time of capture it was as much as 500 feet above the present
level of the Tugaloo at the jucture of the three streams, and
that the grade of the Chattooga at that point, and therefore
necessarily at the mouth of the Tallulah, was before the cap-
ture that much above its present level at the mouth of the
Tallulah.

From an examination of the profile of the Tallulah, as
shown on the map (Plate XI), it will be seen that a lipe of
level from the river bed at the head of the gorge to the Grand
Chasm is 525 feet above the river at the latter point, or ap-
proximately coincides with the brink of the cliff at its highest
point. In other words, if the Chattooga was once 500 feet
above its present level where it is joined by the Tallulah the
latter river could have reached it by an easy grade without
having had to cut a gorge. On the capture, however, of the
Chattooga at a point a short distance below the mouth of
the Tallulah by the Tugaloo, the grade of the first named
river would have been lowered sufficiently to necessitate the
cutting of the gorge through which the Tallulah now flows.
Careful search in the region across which the Chattooga
would have had to flow failed to reveal anything like river
gravel, but subsequent erosion may have entirely obliterated
. the old stream bed.

The theory of capture has lately received corroborative
evidence from a comparative biological study showing simi-
larity in a portion of the unione fauna of the Chattahoochee
and Savannah rivers.* There is also some evidence of forms
in the Savannah system that point to a round-about derivation
from forms of the Tennessee river through former connection
between it and the Coosa river in Alabama and between the
Coosa and the Chattahoochee by way of the Etowah in Geor-
gia, and from the Chattahoochee to the Savannah system by

*CHas. T. Simpson. On the evidence of the Unionidae regarding the former
courses of the Tennessee and other Southern rivers. Scfence, vol. xii, No. 291,
p. 133.

Paleontological Speculations.—Gratacap. eras

former connection at the locality under consideration.”

If the Chattooga originally belonged to the Savannah sys-
tem, and no change of position has taken place, then the next
theory that would seem to suggest itself as explanatory of
the evident recentness of the gorge cutting would be that the
differential movements that are known to have taken place at
the end of the Columbia and LaFayette in some way caused
particular activity in stream erosion at this locality.

Under either theory, however, the absence of a gorge of
similar character in the adjacent Chattooga would appear to
need explanation.

PALEONTOLOGIGAL SPECULATIONS.

L. P. GRATACAP, Am. Mus. Nat. Hist., N. Y.

In the search for those variations whose accumulated force
ushers in new forms in the life series, and by whose influence
on the organism as a whole a kinetic impulse is established in
a new direction, no more useful field of observation can be
chosen than the detailed results of a survey like that of New
York. In these volumes’ devoted to palaeontology we have
displayed with laborious care the whole series of species, with
their variations and blendings, contrasts and modifications,
which the active work of the field, the combined painstaking
labors of many students, and the criticism of a final revision
have gathered, prepared and published.

A very large amount of the material which formed the basis
of these studies ,and a fair number of the type and figured
specimens presefited in the earlier volumes of the New York
survey, and in the Reports of the Regents of the University
are today permanently located on the shelves of the exhibition
cases of the American Museum of Natural History. The ex-
haustive cataloguet of these alone, now partially prepared by
Prof. R. P. Whitfield and Dr. E. O. Hovey, show their ex-
tent, while associated with them are numerous specimens, and

. many large slab groups of species, the whole collection form-

ing, certainly not a complete, but a very instructive view of

*C. W. Hayes, and M. R. CAMPBELL, locality cited, p. 131.
+Bulletin, American Museum Natural History, vol. xi.

76 The American Geologist. February, 200m

palaeozoic life. From these, and the published results of the
survey the following conclusions have been drawn. It is true
that the eye cast over a page of expressive drawings meets
more saliently relieved the physical characteristics, size, orna-
mentation, shape and sculpture of fossil shells and organisms
than it does in a line of selected fossils where the number, the
surficial dullness and imperfection perhaps fail to produce “at
sight” the impression made by luminous and exactingly ex-
ecuted drawings. Still there can be no question that the “orig-
inal specimen” can never be evaded, and for scientific pur-
poses it is of incomparable value. In a field of general obser-
vation, devoid of the extreme precision of “species making,”
or taxonomic study, both figure and specimen can be usefully
studied, and in this paper, conceived as a contribution to evo-
lutional studies, they have been made to supplement each other,
the lack of opportunity and material forcing me to rely on
drawings perhaps more confidently than I should.

Dr. Sacco in his examination of the Tertiary mollusca of
Piedmont* has been impressed with those gradations of form.

sculpture, color, size, etc., which insensibly merge one species
into another, and he deduces some general conclusions, which

are of interest in the examination of any group or succession
of groups of fossils at any horizon. He finds a species, in a
typical condition, has grouped about it more or less aberrant
forms, referable, however, to it; he thinks, by reason of prior-
ity a variety of species is given the name which should be as-
signed to the essential form, which through the custom of
terminology receives another name. He finds some species
mutable and evanescent, others less changeable and dirigible
only between certain fixed limits of form; he finds the ex-
tremely variable the most vitalized, and they are those which
continue for a long series of geological periods, as-“their great
oscillatory polymorphism around a typical form permits them
to adapt themselves to the diverse conditions which succeed
each other in the same region, in different geological periods,”
while more conservative forms disappear or become so fully
modified, as to form new and serviceable species. He notes
the fact that upon ornamented species the progress of change

*Le Variazioni der Molluschi, Dorr. Frprrico Sacco; Bulletino della
Socicta Malacologica Italiana, 1893.

wg ANSE

Paleontological Speculations.—Gratacap. i A

is most evident, that litoral species are more valuable, less
stable than pelagic and abyssal forms, that the varieties of one
period develop into the typical species of another, that this de-
velopment attains a surprising rapidity in some instances, that
faunas “disappear, and again later, under presumably similar
conditions, reappear. Dr. Sacco finds that variations of color
are less important than those of form. He dwells, as many
other observers, on the internal tendency and external circum-
stances as constituting the two influences determining change.
Amongst the latter are first, biological circumstances, as nutri-
tion, enemies, parasites; second, chemical, as nature of ocean
floor, nearness of river mouths, material dissolved in the water ;
third, physical, as light, conformation of the sea bottom, depth,
temperature ; fourth, mechanical, water movements.

His canons of judgment in estimating change, are the ad-
dition or diminution of features, and the gradual increase of
one feature. He insists on the adequacy of the shells of mol-
luscs to resolve the problems of this development. His es-
pecial region of research, the tertiary basin of Piedmont, has
furnished him with a most illustrative exemplification of these
facts of variation, undisturbed by conditions of immigration,
branchings, migration, etc. But he finds himself in carrying
on the great work of Bellardi, involved in perplexities of ter-
minology as to the limits and application of the terms sub-
genera, variety, sub-species, sub-variety, forms, “mutations,”
etc.

Studies of this nature amongst invertebrates have en-
gaged American paleontologists, and they have especially at-
tracted the attention of Prof. Alpheus Hyatt, Dr. R. T. Jack-
mage rot dt. S.' Williams, Dr (€E.-Beecher, ‘Prof: “J. -M.
Clarke and Dr. W. H. Dall. At present the examination in its
entireness throughout the palzozoics has not reached conclu-
sive dimensions, and every additional contribution, if honestly
conceived, cannot be regarded as unwelcome, unnecessary or
inopportune.

Prof. H. S. Williams in Bulletins 3 and 80 of the U. S.
Geological Survey has discussed the changing facies of faunas,
Devonian and Carboniferous, and has indicated how variations
have followed slightly changed conditions, and to what ex-
tent, in the area considered, groups of associated forms com-

78 The American Geologist. Bebruary, 2002

pose characteristic biologic groups that seem to appear and
disappear with an exactitude that expresses their identical re-
lations to similar environments. Indeed he says:* “the pre-
cision with which correlations may be made upon paleontologic
evidence is determined by the knowledge possessed of the re-
lations of the elements of organic form to geologic age, so that
a fragment of a fossil in the hands of one who knows how to
interpret the evidence may furnish a more correct diagnosis of
the age of the formation than a bushel of fossils in the hands
of one ignorant of the laws of organic life determining the
form of the structure produced.” He further in this notable
essay alludes to the “laws of heredity and evolution,” and to
the “law of relationship of organisms to each other and to
geologic time.’ And he concludes “comparisons of allied
species in the same genus exhibits to him the rate and direc-
tion of modification taking place in the genetic history of the
genus, and in the plastic or variable characters he finds a sen-
sitive indication of the stage of development attained by the
race when the particular individual lived.”

A contribution to the genetic relationship of the inverte-
brate fossils of successive beds of the Tertiary was made in
1885 by Dr. Otto Meyert who endeavored, upon the relevant
evidence of evolutional changes, progressive in character, to
overturn the recognized succession of the southern Tertiary
Eocene. The succession of Claiborne (Middle Eocene), Jack-
son (Upper Eocene), Vicksburg (Oligocene), which had been
defined and established by Hilgard, was inferentially reversed,
and the Vicksburg became the oldest, and the Claiborne the
youngest stratum. In this particular instance the paleontolo-
gist was worsted in an encounter with the less yielding and less
supposititious data of the stratigrapher.t But Dr. Meyer’s
contribution lost none of its interest, because of a mistaken in-
terpretation, as an index of the application of biological in-
ferences to the questions of stratigraphy; at least Dr. Meyer’s
genealogical table was in the nature of a remonstrance against
wholesale species making, and was a stalwart introduction of

*Correlation Papers, Devonian and Corboniferous, by HmNRY SHALPR
WILLIAMS ; Bulletin 80 U. S. Geol. Surv., p. 263.
+Amer. Journal Sci. and Art., vols. xxix. and xxx.; pp. 457, 60, 421.

tSee E. W. HiteGarp, The Old Tertiary of the Southwest, Amer. Jour.
Bci., vol. xxx., p. 266.

Paleontological Speculations.—Gratacap. 79

the theory of derivation into geological problems.

Dr. Meyer’s conclusions were based upon relationships of
fauna, as that the lowest Claiborne is more nearly related in
faunal features to the Jackson, than is the highest Claiborne,
etc.; and upon a study of variations, where it was tacitly as-
sumed that the typical form of a species varied from its first
characters progressively in time, giving rise to new species,
as the original or ab-original forms disappeared.*

Dr. Jackson in his now well known essay on the “Phylog-
eny of the Pelecypoda”+ has engaged in the difficult labor of
disentangling a line of descent for the Aviculide from a hypo-
thetical nuculoid shell and a problematic genus Rhombopteria
which he placed in the Lower Silurian and from which
through divergent branches of descent incorporating the
Devonian genera Actinopteria, Ptychopteria, Pterinopecten,
Aviculopecten, Crenipecten, Lyriopecten, Pernopecten (?), he
reaches Pecten, Spondylus, Plicatula, Placuanomia, Placuna,
Perna, Ostrea, Vulsella Meleagurina, Malleus. This compre-
hensive examination of a special section was directed to the
elucidation of a question of descent, and indicated no general-
izations less exclusive than the origin and development of this
group of shells.

Also in Jackson’s and Jaggar’s Studies of Melonites mul-
tiporus, and in the former’s elaborate investigation of the
Palaeechinoideat the biologic processes of development and
the morphological scheme of tesselation in the test the field of
observation was necessarily restricted. In general treatises
such as Gaudry’s{ Les Enchainements du Monde Animal, the
speculative conclusions of evolutional relationship are only
dwelt upon in the general outlines of animal genealogy.

In any general reference to studies of this nature, Dr.
Beecher’s essays on the Development of the Brachiopoda,
Prof. Hyatt’s work on the Phylogeny of the Cephalopoda, and
Dr. Hall’s “Hinge of Pelecypods and its Development” must
be remembered. These are special treatises dealing, with

*A similar mistaken inference with regard to the zoological sequence
in the Cambrian faunas, caused. for a long time, as Dr. Walcott has exnlained,
the superposition of the Olenellus beds over those carrying Paradoxides.

+Mem. Boston Soc. Nat. Hist., vol. iv., p. 277.
jBull. Geol Soc. America, vol. vii., 1895-6, pp. 135 and 171.

{Les Enchainements du Monde Animal dans les Temps Geologiques ; Fos-
siles Primares.

8o The American Geologist. ‘Pebrosry oe

technical precision, with circumscribed questions. They in-
volve great special knowledge and are based upon a careful
comparison of observations along a particular line of zoolog-
ical inquest. But the search for some general tendency, some
broad teleological movement of forms, prevailing as a tec-
tonic impulse over or through a diversity of animal groups
has not been so extendedly followed. Such a search deals
only with primary relations, as size, form, ornamentation, com-
plexity, fecundity.

It deals with more general and simpler questions and it
seems reasonable to expect can be answered by an inspection
simply of the work of the specialists. For, as Dr. Beecher has
said (Origin and Significance of Spines) “the history of a
group of animals is the same. The first species are small and
unornamented. They increase in size, complexity, and diver-
sity, until the culmination, when most of the spinose forms be-
gin to appear. During, the decline, extravagant types are apt
to develop, and if the end is not then reached, the group is
continued in the small and unspecialized species, which did not
partake of the general tendency to spinous growth.” An ad-
equate comparison then of the phylogenetic work done in dif-
ferent sections of animal life might reveal general tendencies
or laws. It is not difficult to see that it does. In this paper
the suggestions are derived from an inspection of the Hall
Collection.

SIZE AND SKELETON MASS.

It is evident that in any animal series the primary mem-
bers are small. It is inconceivable that a group of animals
where the members attain any considerable size can on its first
appearance in geological time assume complete physical devel-
opment. An inspection of the Lower Cambrian faunas shows
this diminutiveness. With the exception of trilobites the
forms are small. The genera /phidea, Acrotreta, Linnarssoma,
Lingulella, Kutorgina, Obolella, Orthisina, Fordilla, the patel-
loids, (Scenella, Stenotheca), and the pteropods(?) all ex-
press molar immaturity. Organization preceded _ skeletal
deposition.

This fact has considerable interest and appears to contain
suggestions of phylogenetic importance. If we find in a fossil

Paleontological Speculations.—Gratacap. 81

fauna well developed skeletons or thickened hard parts (shells,
carapace, hinges, etc.), we may conclude that the group rep-
resented has attained functional equilibrium, and has existed
longer than similar organisms of less physical mass or internal
osseous or shelly deposits. The simple and obvious condition
prevalent in individuals has an adumbrant genetic application.
While it is unquestioned that favorable conditions, stimuli
both of health and food, accelerate the deposition of hard
parts, yet it is certainly clear that age brings, of necessity ac-
cumulation of material, both because secretion has _ acted
through a longer period of growth, and that in senility the
turgor of the secreting membranes so increases as to give rise
to heavier depositions of mineral substances (calcification).
And it seems a just inference that at the inception of a
group of organisms their physiological relations precede the
skeletal sequelz of these relations, that if hard parts are se-
creted in the early stages of an organism’s history the func-
tion of their secretion increases by use, by heredity, through
time, and the habit of forming them is reinforced and extended
as the organism is geologically older. It is conceivable that
the mollusca began in shell-less or almost shell-less organ-
isms,“ that the acquisition of shell, the elaboration of hinge
teeth and even the interlaminal deposition of “loops,” “arms,”
or internal appendages as mineral or hard parts was slowly,
with a slowness sensibly reflected in their paleontological
phases, consummated. Or, in other words, the appearance of
well developed hard parts internal or external, skeletal or teg-
umentary, marked an evolutional climax. This is really an or-
dinary assumption. The biology of the mollusca, and crusta-
ceans, and echinoderms shows the secondary and subsequent
development of the hard parts. They are themselves sympto-
matic of the finished phases of embryological changes. An in-
complete power of secretion must have marked the earlier
phases of histological growth. In the evolutionary process the
heavier armored, thicker shelled, harder carapaced organisms
must have followed the more slender fragile and tenuous cov-
ered animals.
te ae ie Siiurlachen, Crantaden der Geleian te iat, aoe eee
Gotlands, bel FrimpricH BARON HOYNINGEN Heunr. Verhandlungen der Rus-
sisch-Kaiserlichen Mineralogischen Gesselschaft zu St. Petersburg, 1899). Dr.

Beecher has already furnished the evidence to show that the progenitor of
the brachiopod phylum was Kutorgina.

82 The American Geologist. Febuary ae

Of course this is a general proposition. Selection might
rapidly augment the growth of hard parts in some sections of
animal life, and comparative immunity from attack or injury,
retard or but laboriously develop them in others. There
seems no advantage in either size or mass except so far as
one or the other, or both, enable an animal to resist destruction
or in predatory examples, chase its prey.

The impression, very quickly and keenly felt in examining
Cambrian fossils, is that they are small and thin. The trilobites
remain conspicuously contrasted with their associated fauna,
and suggestions are also evident that the worms may have been
large. The morphological impulse which produced large trilo-
bites and worms and left everything else small is not without
interesting suggestions, especially as the largest and strongest
examples are Middle or Lower Cambrian.

But primarily, is it true that Cambrian life exhibits diminu-
tive and fragile forms? It certainly seems to. There are no
large brachiopods, no corals of appreciable size, no large lamel-
libranchs, no crinoids, few and insignificant univalves. The
character of the fauna in these respects is provisional and in-
troductory. The examples of Brachiopoda belong mainly to
the inarticulate group wherein functional organization is high,
but the later secretatory activities, those which made shells,
loops, teeth, etc., which became excited and specialized under
new conditions or accidents, were yet dormant. Dr. Walcott,
in his ‘‘Fauna of the Lower Cambrian or Olenellus Zone,” has
furnished a review and exposition of what is known of the
fauna of this early age. It presents a scattered and broken out-
line, as from the circumstances was inevitable, of the inverte-
brate forms of life. It can be, as far as research has gone,
neither full nor complete. The forms of life are small and
feeble. The trilobites alone, and the worms, present evidences
of abundance and development and strength.

In the Hall cabinet Lingulepis pinniformis, Obolella polita,
Lingulella mosia, L. aurora, L. stoneana, in the western Pots-
dam are numerous and indicate zones or areas of successful
multiplication. In the Troy limestone beds Lingulepis mini-
ma, L antiqua, and Obolella prima seem also plentiful. The
trilobites present in the western sandstones the familiar feature
of great numbers. The annelidan indications are necessarily

Paleontological Speculations.—Gratacap. 83

suggestive, but in Scolithus linearis, Arentcolites woodt, the
Myrianites and Nereograptus of Waterville, Kennebec R.,
Maine, we have plentiful evidence of their wide distribution.
The significance of the trilobites and the striking annelid
indications cannot be overlooked. Before passing to these the
thought of Size and Mass, in connection with development, sug-
gests, with reference to trilobites, an idea of discrimination in

- regard to age. If the development of exoskeletons, hard parts,

hinges and bony or chitinous coverings, is a mark of advanced
biogenetic age, then as between two groups of trilobites whose

‘relative antiquity is under discussion that group which presents

the greater surface of such members is the younger. Should
such a consideration have led a priori to the assumption of the
greater age of Olenellus as compared with Parado-xides, because
of the marked pygidial enlargements in the latter over the for-
mer? For in Olenellus the lateral lobes of the pygidium are
absent, the axis alone remaining, while slight pygidial wings
are incipient in Paradoxides. The growth of pygidia is notice-
able in the trilobites of the higher Cambrian series, as in Pty-
choparia (Conocephalites), Dicellocephalus &c.

In Agnostus and Microdiscns the dual development of
head and tail is certainly conspicuous, but their category of
growth and relationship is entirely different from the mul-
tipleural forms represented in Paradoxides and Olenellus.
Olenoides shows also a uniform growth of head and tail. The
impression given by a study of these early trilobites is that they
were separated in habits of life into two groups, a rapidly mov-
ing natatory group like Olenellus, Protypus and Paradoxides
with well developed head shields from mechanical reaction
against pressure, and a sedentary group in which glabella and
pygidium were more evenly related. And that between these
extremes Conocoryphe, Ptychoparia, Ellipsocephalus, Agrau-
los, etc., presented a less determined phase of activity or rest.
These considerations, of course, have no reference to their mor-
phological affinities. There is certainly a definable relation be-
tween activity and cellular deposition of hard parts. Embry-
ology proves that. The early stages of many sessile organisms,
which develop in their maturity hard parts and more or less
significant exoskeletons, are marked by great motility and ex-
cursive power. Such are the free-swimming larve of the Mol-

84 The American Geologist. POM

lusca, the Pluteus of the echinoderms, the Nauplius and Zoea
of crustaceans.

At any rate in looking over this phase of fossil forms in
the Hall collection the skeletal development of the trilobites is
an impressive fact.

If we take the enumeration of species given by Walcott in
Bulletin U. S. Geological Survey No. 30, we find the relative
percentages of the zoological elements of the Cambrian faunas
in North America to be as follows:

Algae i. sis. cea ove. d5 ss) EO) SDP aChiOpoda."... . .. .5s go een
Sponpiaé -.. 22009. e. 32... . 3.30 “Lamellibranchs:.«..<.’. 2+25 ae
Bl ydrozoa. Foy sake ee i os ko EEF MASERU OPOG A os hei ctiy cos eee 7.357,
Cringidea \ricis eA. a ayes Pteropada ts, 26 «0220 es
Ammelida: Jos 0. bis obo. Ey rtStaceatise 4 23) ot.
Srilobites oo a eee Heo

The number of species in the trilobites more than equals, in
its percentage of all (?) tabulated species, that of all the re-
maining forms of life. And when we consider their numerical
proportion in individuals, and examine the blocks of friable
sandstone from St. Croix or Trempeleau, Wis., we find they
rival in individual enumeration the brachiopods. In short the
trilobites in the Cambrian clay clearly suggest biological prefer-
ment.

In the ninth lecture in Dr. Brooks’ series on the Founda-
tions of Zoology wherein the question discussed is natural se-
lection and the antiquity of life, the author places, after the ini-
tial stages of zoological development, the scene of the faunal
growth on the floor of the ocean. He says, “I shall give reasons
for seeing, in the Lower Cambrian, another period of rapid
change, when a new factor—the discovery of the bottom of the
ocean—began to act in the modification of species, and I shall
try to show that, while animal life was abundant long before,
the evolution of animals likely to be preserved as fossils took
place with comparative rapidity, and that the zoological feat-
ures of the Lower Cambrian are of such a character as to in-
dicate that it is a decided and unmistakable approximation to
the primitive fauna of the bottom, beyond which life was rep-
resented only by minute and simple surface animals not likely
to be preserved as fossils.’”’ Dr. Brooks’ assertion that ‘“‘on the
old Cambrian shore the same opportunity to study the embry-

Paleontological Speculations.—Gratacap. 85

ology and anatomy of pteropods, and the gasteropods and
lamellibranchs, of Crustacea and Medusz, echinoderms, and
brachiopods, that he now has at a marine laboratory” seems, if
literally interpreted, misleading. Neither is the assumption of
a sea bottom, in any abyssal sense, for the Cambrian fauna, at
all warranted. The fossils are found for the most part in shore
and off-shore deposits. In looking over the Cambrian speci-
mens in the Hall collection Dr. Brooks’ speculation, taken in
connection with suggestions made by Simroth, (Entstehung der
Landthiere), give however a peculiarly fascinating provoca-
tion for a supplementary assumption. In a passage of Sim-
roth’s of much interest the following observation occurs: “A
priori the contact of both (land and sea) must form the prob-
able area of the original creation, where both essential factors
engaged each other. Therefore the oceanic Bathybius, already
._ discredited by observation, would be found, as source of life,
theoretically impossible or at least improbable. And it re-
mains to ask where,in that plane of contact between the atmos-
phere and the hydrosphere, the most strenuous exchange unin-
terruptedly occurred, whether on the open sea, or in the coast
line. The answer to me appears unqualifiedly to indicate the
latter. If we assign, as has been done, to the great waves of the
ocean a breathing function, then the surface of the lung pass-
ages through whose agency the respiration is effected, must be
sought in the tireless movements along the shore, which would
be assisted by the foam-masses of the free waves, even if only
intermittently aided by stronger breezes. In the high seas, air
and water come in contact with one another, but at the beach,
water and land, and here the saturation with gas and mineral
solutions is equal. But as it is from these opposite elements all
interaction issues and depends, then at this position the centers
are to be sought from which the organic impulse took its rise,
radiating in two directions, seaward and landward.”

Such a provisional locus for the inception of life might have
resulted, at that moment when the cooling elements had ac-
quired a proper chemical intricacy, for its creation, in a series
of protistic bodies such as Pfluger has assumed, unreasonably
it seems, existed in one great single concretion. He says, “ac-
cordingly I would say that the first proteid to arise was living
matter, endowed in all its radicals with the property of vigor-

86 - The American Geologist. webraary,; Sia
ously attracting similar constituents, adding them chemically
to its molecule, and thus growing ad infinitum. According to
this idea living proteid does not need to have a constant mole-
cular weight; it is a huge molecule undergoing constant never-
ending formation and constant decompositien and probably be-
haves toward the usual chemical molecules as the same behave
towards small meteors.”

These protistic bodies,* formed at the margins of the in-
sular masses in the primeval ocean, and beginning the develop-
ment of derivative forms shoreward and seaward as Simroth
suggests, originated two faunal expressions, an annelidean
type along shore, a molluscan type in deeper water, and this
deeper water fauna shows, at least in its totality, an increase in
size and skeletal mass. Do not these Cambrian remains lend
support to these curious propositions?

In Europe practically the Cambrian rocks are shore de-
posits. Their general character has been summarized by
Geikie as follows, “the rocks of the Cambrian system present
considerable uniformity of lithological character over the globe.
They consist of gray and reddish grits or greywackes, quartz-
ites and conglomerates, with shales, slates, phyllites or schists,
and sometimes thick masses of limestone. Their false bedding,
ripple marks, and suncracks indicate deposit in shallow water
and occasional exposure of littoral surfaces to dessication.”
In America, as is well known, the limestone beds are well
marked. At Troy, New York, Rutland, Vt., and in Nevada,
Cambrian limestone strata have been described by Ford, Wolff,
Foerste, and Walcott. Limestone beds of this age also occur
in the St. Lawrence valley, in Newfoundland, in Arizona and
Utah.

But these limestone beds though they may be regarded as
distinctively belonging to offshore or deep sea sedimentation do
not properly express the Cambrian geological facies. They are
essentially exceptional, sporadic and ultra-limital. They pre-
sent an invasion of a sea, and one in which we believe was being
formed that more adequate and complete molluscan faunal ex-

*In a biological sense it is not unreasonable to bring in relation with.
these the pre-Cambrian radiolarians and sponges found by L. Cayeux (Bull.
Soc. Geol. de France, 1894; Am. Soc. Geol. du Nord, Vol. xxiii, 1895). The
sponges found by M. Cayeux were enclosed in phtanytes, and gave evidence
of strong marine currents in shallow water.

Paleontological Speculations.—Gratacap. 87

pression of the Ordovician time. To be sure the fossil remains
from these limestones are mainly Cambrian, but apart from the
fact that these limestones have not been thoroughly explored
their relations to the shore fauna, (properly to be considered
Cambrian) as an invasion of the deep sea would have led to the
deposit of Cambrian genera and species within them, while

_ their own more characteristic residents, beyond the continental

limit, might not have at once followed them inland. The pter-
opodous species of these limestones are pelagic and might have

‘naturally moved shoreward with the deepening of the Cam-

brian shore-line. Where indeed their fossil contents are typ-
ically Cambrian the limestone seems generally arenaceous or
of a shore origin, and in these cases it is not clearly shown
that the fossils are as numerous in individuals or species as
those of the slates and sandstones, nor whether they represent
fossilized individuals im situ, or current-transported specimens.
In many cases the fossils of the limestone suggest the presence
of an articulated brachiopodous fauna, or one of greater size
and skeletal mass, as contrasted with the inarticulates of the
Cambrian shallow waters. So in Ford’s Troy section Orthis,
and Leperditia (Plectambonites) appear, and in the limestones
of the Nevada sections the predominance of A gnostus* and Pty-
choparia indicates an Ordovician affinity, while other genera of
triolbites (Protypus, Dicellocephalus, Olenoides) being
glabellate(?) and therefore of relatively more skeletal mass,
are later forms than the Olenellus or Paradoxides and point to
an outlying bathymetric fauna.

If this proposition receives further corroboration we are pre-
sented with a biological picture of this sort.

Along the Pre-Cambrian coast-waters a process of devel-
opment or creation, ensued from such protistic bodies as may
have secured proper elaboration, which resulted in a synthetic
type of annelids. From these in divergent directions came the
trilobites and the brachiopods, the latter deviating into the
heavier shelled genera and families in deeper water, and rep-
resented in shallower depths by the ecardines, the former mul-
tiplying in swimming forms along the coast with the more

*Agnostus extends into the second fauna and also has a very wide geo-
gravhi al distrbution in the primordial rocks. In fact Barande states the

single connexion between the primordial and the following faune is through
Agnostus.

88 The American Geologist. February, 1901-

carapaced, sessile, and seminatatory forms in deeper water.
This assumption is hardly violent to those who have
watched the tendency of recent biological speculation. Ernst
Haeckel in his History of Creation pointed out the archetypal
character of the metameral vermes; “‘the phylum of Worms,
on the other hand we have to conceive as a low bush or shrub,
out of whose root a mass of independent branches shoot up in
different directions. From this densely branched shrub, most
of the branches of which are dead, there rise four high stems

with many branches. These are the four lofty trees just men-'

tioned as representing the higher phyla—the echinodermes, Ar-
ticulata, Mollusca, and Vertebrata. These four stems are di-
rectly connected with one another at the root only, to-wit, by
the common primary group of the Worm tube.” In the com-
munication of Prof. J. Beard of the Anatomisches Institut,
Freiburg, to Nature (Vol. XXXXIX, p. 259) on “Some An-
nelidan Affinities in Ontogeny of the Vertebrate Nervous
System’ he remarks that “if we are ever to trace the ancestry
of Vertebrates at all, the nervous system will probably form a
significant factor in the solution.”” But it 1s the arthropods
which resemble the ringed worms in possessing “a very char-
acteristic form of the central nervous system, the so-called ven-
tral marrow, which commences in a gullet-ring encircling the
mouth.” (Haeckel). If the nervous system then is an index of
affinity, it serves in the case of the crustaceans to point also to
their annelidan origin. Gegenbaur (Comparative Anatomy )
shows that. He says “the nervous system of the Arthropoda
resembles that of the Annelides with which it completely agrees
in its fundamental characters.” Simroth says emphatically “so
entirely can we see the agreement of the ancient animals in a
sum of features that, without further effort to unite them, we
demand a common root for their common derivation. What
was this? No one can conceive of anything else than an Anne-
lid, and certainly, because of the development of the necessary
paropodia for the growth of the articulate members, of a marine
Polychaeta.”

The pre-Cambrian age was the age of Worms. The rocks
of the Cambrian offer evidence of this. The annelidan traces
in the Potsdam slates and sandstones, shales and flags exceed
those of any similar beds throughout the palaeozoics.

Paleontological Speculations.—Gratacap. - 8y

Scolithus is prevalent in Potsdam layers, the chloritic slates
of the Kenebec river, Maine, are thickly covered with the trails
of worms (Chaetopods?), Arenicolites, as determined by Whit-
field, fills broad spaces of the Barriboo beds in Wisconsin. Nath-
orst has indicated the numerous traces of annelidan tracks in
Scandinavian Cambrian. Climactichnites and Protichnites
may all be the reptant impression of large broad ringed worms.

It seems impossible to reject the patent suggestions of bi-
ology which are thus partially reinforced by the indeterminate
but significant instances of fossil traces.

In considering further the hypothetical picture of primor-
dial zoic tendencies the condition seems obvious that in shallow
water forms—the trilobites and ecardines—we have chitinous
integuments, in the deep water calcareous, mainly presented.
This seems connected with initial histological peculiarities
which no refinement of chemical biology can yet completely
touch. The contrasting and separative features between a
shore and a deep-water existence are of course primarily the
longer exposure to light, and greater likelihood of mechanical
violence, on the later removal from these vicissitudes and sub-
jection to pressure with a richer supply of dissolved mineral
materials.

Simroth in his interesting section “Einfluss der Atmosphare
auf das Integument,” has offered some instructive parallelisms,
symptomatic, in the case of the shore animals, of the stages in
their assumption of hard coverings. The hardening of the
epidermis by exposure to air and light led he thinks to the
gradual replacement of the hairy surfaces of the worms by
soft chitinous coats, which grew stronger and thicker as the
metamorphosis went on and the changes to such a triplicate
exoskeleton, as the arthropods possess, were completed.

The Brachiopoda have been clearly considered referable
to the annelids. Prof. Sedgwick believes “we must assign to
the group the position of an independent phylum of the animal
kingdom with affinities, by the form of their central nervous
system and by their setae, by the presence of a well-developed
perivisceral coelom and a canalicular haemocoel, and by the
traces of an imperfect segmentation, to the Annelida.” We
find therefore the phosphatic thin shelled atrematous Brach-
iopoda and the chitinous covered trilobites well represented

90 The American Geologist. February, 100%,

along the Cambrian beach line, and we are led to accept for
them an annelidan origin. It is, as we pass upward geologically
in the inspection of these classified fossils of the Hall collec-
tion that we meet, in the deeper seas of the Calciferous group,
a development of size and skeletal mass in the heavy shelled
brachiopods, gasteropods and cephalopods.

If the acquirement of hard parts by the shore fauna was
due to the siccative influences of their position, their response
to light stimuli, and their gradual assumption of protective coats
against the violence of waves, the more robust and calcareous
groups which succeed them may be related to water pressure
and the bountiful supplies of dissolved mineral elements in the
deeper seas. I do not know where to turn for evidence on this
point. Barotaxis has been by Verworn distinctly indicated as a
physiological agent. “Every degree of pressure can act as a
stimulus, from crushing or cutting, which destroys the con-
tinuity of the substance, down to the slightest touch and the
most delicate change in the pressure of the air or the water
that surrounds the organism.”

Now it is an accountable supposition that this pressure of
water originally exercised a stimulating influence upon organ-
isms prepared to secrete shelly coverings, and that while on the
one hand the crustacean forms and inarticulate brachiopods in
their evolution from annelidan ancestors along the shores, de-
veloped their thin chitinous and phosphatic tissues, the mol-
luscan and coelenterate life in the deeper waters was forcing
its energies into the manifold elaboration of calcareous coats
and skeletons.

Dr. Dall in his address at the anniversary of the Biological
Society of Washington on Deep Sea Mollush:s indicated the
conditions prevalent at the sea bottom. The great hydrostatic
pressure, the presence of carbonic acid, sub-marine currents
both acting as mechanical sweepers and food-carriers, darkness,
the absence of vegetation, and a recourse for nourishment to
foraminifera and the rain of pelagic organisms from the sur-
face are therein mentioned. But perhaps as bearing on this
question of the sudden evolution of the next fauna above the
Cambrian, and which it is intended here to regard as of deep
sea origin, are his reflections on the absence of conflict in the
abyssal or archibenthal (semi-abyssal) regions. He said “the

Paleontological Speculations.—Gratacap. gI

animals belonging to the Mollusca which are found in the
archibenthal and abyssal regions, especially the latter, do not
live in a perpetual state of conflict with one another. A certain
amount of contention and destruction doubtless goes on, but on
the whole the struggle for existence is against the peculiar-
ities of the environment and not between the individual mol-

lusks of the area concerned. It is an industrial community,
feeding, propagating and dying in the persons of its members

and not a scene of carnage where the strong preys upon his
molluscan brother who may chance to be weaker. Hence the
course of evolution and modification, though still complex, is
certainly much less so than in th shallower parts of the ocean.”
Now in the early seas there were probably no depths comparable
with the abyssal spaces of modern oceans. The fauna which
arose and may have been partially contemporaneous with the
Cambrian and which as a stratigraphic fact we find overlying
the latter, was evolved in an offshore, and not necessarily pro-
found basin. If freedom from competition and from destructive
foes is true today in deep sea animals it was, especially as
fishes were absent, more markedly true of these primal groups,
and this may have produced that uniformity, a general evenness
and similarity of shell-life, without strong or salient variations,
which certainly is apparent in the Cambro-Silurian beds of
fossils. ?

At any rate it is certain that passing into the next section of
the Hall fossils we encounter the evidences of a new fauna, one
especially emphasized by the discoveries in Vermont of Profs.
Brainerd and Seely. It is a limestone fauna, a deep sea
fauna, and its development upon a scale of such magnitude
with such diversity of fauna, with such a systematic zoological
overthrust upon all Cambrian precedents, leads clearly to the
conclusion that its growth extended far back in time and
brought it, at its inception, into contemporaneity with the shore
fauna of the Cambrian formations. Size and_ skeletal mass
are now very obvious in molluscan life.

Conditions of life were probably identical with those of to-
day so far as the propagation and maintenance of genera and
species were concerned, and, as today extreme deep sea (abys-
sal) areas are inimical to animal abundance, the faunas, suc-
ceeding the Cambrian, if formed in deep water, may have

g2 The American Geologist. Rebrasey ae

moved shoreward upon a deepening of their former habitat
when crustal shortening or the slow folding of synclinal
troughs, from sedimentation, occurred.

While it seems naturally a fair speculation that the influ-
ence of pressure would have upon developing molluscan or-
ganisms the effect of hastening their secretive functions, and
that such influence might have been the original cause of
establishing the shell forming habits of molluscan animals,
we may further consider the thermal conditions of deep water
in those early days. It must have presented sensibly high ther-
mal phases, and, to quote Verworn, “everywhere in living
nature the law is met with, that within certain limits increasing
temperature acts to augment vital processes.”

This increase in temperature in the first days of oceanic life
arose from the convexion of heat radiated from the cooling
continental masses. The raising of lithic masses by contrac-
tion must have imparted heat to the seas while indeed their
bottom waters rested upon the cooled surfaces of an original
cosmic fireball. It was such thermal conditions that directly
contributed to an increase in the mineral constituents of the sea
water, and might have in this way also hastened the develop-
ment of shelly parts in sea animals. |

The Calciferous sandstone as revealed by Hall was a silice-
ous shore deposit, and only the records made in the Champlain
(Seely and Brainerd) basin display its unequivocal bathic fea-
tures. The fossil remains present a cephalopodous and gas-
teropodous fauna. Brachiopods of sensible dimensions and rep-
resenting the articulate phylum appear, and we find that with
the exception of corals and crinoids the palaeozoic biologic im-
pulse has reached molar expression. The initial stages have
been far passed. The divergences in genera and classes are
thoroughly established. The partial introductory phase of the
Cambrian day with its eccentric development of trilobitic
forms and its thin shelled brachiopods has been succeeded by
a multivarious and expounding series of organisms heavily
armored in calcareous coverings.

From this point onward throughout the palaeozoic series
the application of the significance of Size and Skeletal Mass
is generally evident. Let us consider the separate fossil
groups. The inarticulate brachiopods present noticeably lar-

Paleontological Speculations.—Gratacap. 93

ger forms, and in the Upper Silurian develop into the large
and internally elaborated Trimerellidae. .

The size and skeletal mass of the inarticulate brachiopods
reached its maximum in the Upper Silurian. The articulate
brachiopods show increasing size, and increasing internal
shelly deposits (loops, hinges, cardinal areas, etc.,) from the
Cambro-Silurian upward. The Rhynchonellide, Orthide,
Strophomenidae gradually yielded their numerical supremacy,
while advancing themselves greatly in size. They become di-
minished elements in the fauna of the upper rocks, as they be-
come more numerously accompanied by the spiriferoids which
attain large dimensions in the Devonian and Carboniferous
and exemplify the extension of interior calcareous appendages
and hinge growth. In the Carboniferous (lower) the families
of Orthidae and Stropheodontidae also attain large size. The
lamellibranchs increased in size continuously to the Devonian,
and through the latter age became conspicuously developed.
The gasteropods attained large proportions in the Devonian.
The cephalopods were, in the straight forms, strongly devel-
oped quite early in the, series and through the coiled genera
continued their growth and accretion to the Jurassic, while in
modern seas they have attained huge proportions, but without
shelly coverings.

The crinoids were slender, small calyxed, long armed, in
the Lower Silurian, and through manifold divergences, with
sporadic and sudden offshoots reached the thick, heavily
plated, short armed, stout pedicelled groups of the Devonian
and Carboniferous.

When the separate genera or families are examined this
progression of size and skeletal mass to certain maximum
points, followed by an apparent decrescence immediately or
subsequently introduced, is very striking. Its theoretical inter-
est lies in the impossibility of referring this universal tendency
in molar character to natural selection, or any series of influ-
ences purely external to the organism.

The considerations which warrant this conclusion are not
so much drawn from particular instances as from the general
tendency throughout these animal fossil forms. That size,
stronger, larger shells, internal shelly partitions, surfaces of
attachment, hinge definition and interior branchial elaborations

O4 The American Geologist. February; 100%

might prove of material value in Mollusca, and through the
aggregate effect of stability, power of resistance, and mechani-
cal aptitude help any genius, enjoying these features, in the
struggle of survival, and so lead to new and more advanced
developments of the same elements, is quite possible, but it is
clear that the fact of this development of size, skeletal mass,
etc., throughout the organic impulse in the past, is more pro-
foundly conditioned.

In the first place the perpetuity of slight, small forms is
quite as great as that of larger forms. The Lingula has out-
lasted a wide range of heavier and more imposing brachiopods,
and the unprotected cephalopods survive the marvellous
“straight horns” and ammonites of ancient seas. The frail
crinoids of our present ocean bottoms continue a line of de-
scent quite contrasted with the well plated, high calyxed, teg-
menated, and massive species of palaeozoic time. Gaster-
opods and lamellibranchs have continuously enlarged up to
present times, but the mere aspect of size, thickened shells and
involved hinges seems in their case also utterly incomprehen-
sible on the supposition of a survival. All the more so as along
with the increase there continues a stream of small forms. It
shows a distant biogenetic tendency. Even if natural selection
finds in increase of size and molar complexity a field of ad-
vantageous activity the continuous expression of these things
reveals an implanted, not a succedaneous, motion in life, and,
partially at least, illustrates Prof. Oskorn’s dictum (Cart-
wright Lectures, 1892,) “that evolution advances largely by
the accumulation of definite variations, or those in which each
successive generation exhibits the same tendencies to depart
from the typical ancestral forms in certain parts of the body,
and that these tendencies stand oui in relief among the diffused
kaleidoscopic or fortuitous anomalies.”

It remains for the conclusion of this first part of the pres-
ent paper to demonstrate the fact of the growth in size and
skeletal mass of the invertebrate forms of palaeozoic fossils.
It is true that there is no consecutive line of symmetrical
growth traceable upward with uninterrupted precision to a
climax, with a subsequent regular decrescence. It is also true
that along with growth in size and solidity and skeletal thick-
enings and irregularities small primitive forms survive and

Paleontological Speculations.—Gratacap. 95

new ones equally small appear. It is true that there are alter-
ations and waves of advance and retreat, that a group of
strongly developed organisms may be followed by less de-
veloped examples of the same groups. But looked at broadly
and carrying the eye forward rapidly the impression is unmis-
takable that there is a tendency to molar expansion, sixeletal
growth, and that from some maximum point there may be
recession and that both seem essentially independent of en-
vironment, and are inexplicable on the assumption of the “Sur-
vival of the Fittest.”

To begin with the linguloid and obelloid shells can be
traced upward to Trimerella through a series of increasing
size and changing internal hard parts or shell buttresses, while’
nowhere do large sized individuals signalize the first appear-
ance of a family. Dr. Clarke in the first particular instance
offers convincing evidence. He points out (Pal. Vol. VIII.,
Geol. Sury., N. Y.) that a line of succession from a linguloid
shell through two divergent lines can be traced to the large
heavy Trimerellas with internal platform, prominent cardinal
areas, solid and lengthened umbo. One line is through Lin-
gulella, Lingula, Lingulops, Lingulasma, the second through
Obolella, Obolus, Elkania Dinobolus. Whether this is a true
genealogical series or not it is a very clear proof of assumption
of size and skeletal mass through successive formations, of a
group of ecardines, though Lingulops is a small shell, and
serves the purpose only of advancing internal structure. Lin-
gulasma, on the other hand, is a quadrate strong and well de-
veloped shell, and, as Dr. Clarke shows, is “to be regarded, in
unison with other features, as evidence of progress in the
assumption of the characters of the large thick-shelled Trim-
erellids.” In the other hypothetical succession Obolella is a
small sub-circular shell with an area; Obolus is a large shell,
Elkama is a doubtful link and a small shell, Dinobolus is a
large platform-bearing shell and in the American Niagara (D.
Conradi) presents approximative features to Trimerella.

Again Lingulepts is a primordial linguloid shell, and is lim-
ited in its distribution to Cambrian beds, but increase of size
is symptomatic even within these limits. The L. minima and
L. antiqua of the N. Y. Potsdam are small, the former an in-
conspicuous shell, whereas L. pinniformis, the western form

96 The American Geologist. February, 1901.

(Minnesota), is a much larger, stronger and thicker shell, and
the beds at St. Croix, where it is so numerous, are considered
later or Upper Cambrian, indeed, might be so considered upon
this evidence alone.

Obolella is a primordial genus, but the evidence of in-
creased size, with geological age is not at all clear. The N. Y.
species, O. crassa, is much larger than O. polita of Wisconsin,
but if Lingula prima Conrad, is Hall’s O. polita, as Prof.
Whitfield claims, the argument still holds as the western form
in this exact instance is much larger than its eastern and ear-
lier representative.

Turning to Discina and Crania we find this general propo-
sition still obviously sustained. If under Discina, so far as the
elements of this inquiry go, we group the discinoid shells
Discinisca, Orbiculoidea, Schizotreta, Lindstroemella, Roemers
ella, we find the increase of size well shown. The small Or-
biculoideas of the L. Silurian becomes the large O randalli and
grandis of the Devonian.

Lingulas increase in their dimensions from their first ap-
pearance, and it is the acuminate type which prevailed in the
earliest faunas (Clarke) which is succeeded by the broader,
more developed forms, while, as indicated by Clarke, Barroi-
sella, with its deltidial hardenings, coming in in the Devonian,
continues the Lingula type until there is “an evident tendency
to span the interval between the so-called inarticulates and ar-
ticulates.”’

Trematis, as confined apparently to American Silurian
faunas, shows a sensible increase in size and general develop-
ment, if terminalis of the Trenton is compared with mille-
punctata of the Hudson River group.

In the articulate brachiopods this same organic impulse is
distinctly presented. In the feature of increasing articulation
Dr. Clarke has said, ‘‘with rare exception these modifications
in each group appear to be progressive, extending along cer-
tain lines of development, and finally acquiring an extravagant
manifestation which may terminate abruptly or result in the
degeneration and obsolescence of some of the parts.’

The spiriferoids reach a climax of development in the De-
vonian and Carboniferous. The increased size and the ampli-
fied cardinal and hinge features reaching such complexity as

Paleontological Speculations.—Gratacap. 97

is shown in Syringothyris, contrast with the incipient stages of
growth and structure in the spirifers of the Silurian.

The strophomenoids from the leptenoid (Rafinesquina)
shells of the Silurian show a constant enlargement with vary-
ing offshoots or auxiliary branches, to the huge Productus
and Stropheodontas of the Devonian and Carboniferous.

The first pentameroid shells are small and the later species

of the Upper Silurian attain magnificent proportions with in-
creased internal calcifications.

As the heterogeneous commixture of forms originally
placed under Orthis have undergone at Dr. Clarke’s hands a
thorough revision and reassortment, their continuity from for-
mation to formation is considerably broken, and many of the
new genera are restricted to single formations. But in Platy-
strophia (Orthis biforata, O. lynx) there is from the Chazy to
the Clinton and Niagara, and especially prominent in the Cin-
cinnati beds (Hudson River) the same obvious increase in size.
Dalmanella testudinaria of the Trenton strengthens into per-
elegans of the Low. Helderberg, Rhipidomella circulus of the
Clinton into R. burlingtonensis of the Carboniferous, Schizo-
phoria multistriata of the Lower Helderberg. The atrypoid
Zygospira becomes later enlarged into the true Atrypas, which
themselves in the same species (A. reticularis) persistently in-
crease in size (see Clarke’s observations, Pal. N. Y., Vol.
VIIL., pt. II., pp. 167-172). It is unnecessary to pursue a self-
evident contention further.

Wachsmuth and Springer have expressed (North Ameri-
can Crinoidea) in crinoids their unwillingness to construct a
genealogical tree, “because such representations are generally
unsatisfactory.” But in this very general proposition the evi-
dence of an inspection of the species from the Silurian to the
Carboniferous shows conclusively that size and skeletal mass
increased, and that whether or not “palaeozoic crinoids repre-
sent, in a broad sense, the larval stages of recent crinoids,” the
movement in massiveness from the Silurian to the Carbonifer-
ous is, amongst them, evident. The large heavily plated
Eucalyptocrinus of the Niagara was a sporadic (Calypto-
crinidae) and short lived development, but it would be an in-
supportable hypothesis that Eucalyptocrinus was an ‘unan-
nounced development.

98 The American Geologist. Bebruaryy 1005.

The cephalopods of the Cambro-Silurian were small. Or-
thoceras (Kionoceras) laqueatum, O. sordium, O. cornu-orys,
O. bilineatum, O. explorator of the Chazy or Calciferous, and
the species determined by Dwight, those of Billings’ Palaeo-
zoic fossils and Hall’s examples were nearly all narrow, short
species. In the Trenton the large Orthocerata appear. Sim-
ilarly the Lower Silurian Cyrtoceras, Gomphoceras, Phrag-
moceras precede the Niagara forms sensibly heavier and more
developed.

The trilobites which were large in the Cambrian, and thin
skinned (?), become in later ages more calcified, heavier cara-
paced, with enlarged pygidia.

Variant, as at some points this conclusion may seem, the
conclusion of growth in size and increased functions of mineral
secretion is almost invariably forced upon us from an inspec-
tion of the fossil lines of growth. It utterly dispenses with
any claim of novelty. But it seems as if it might be more
generally recognized as a guide in the correlation of the hori-
zons, geographically separated and characterized by the same
fossil species. If we find a faunal expression in forms strongly
developed, with larger fossils, and associated with increased
skeletal deposition of parts, it is a reasonable conclusion that,
apart from any or all considerations of improved food supply,
climatic auspices, or freedom from enemies, the horizon is sub-
sequent to those in other sections, possibly holding the same
species, in which these fossils are less developed, generally
smaller and unassociated with morphological complexity.

Questions of correlation are deservedly regarded as involvy-
ing a momentous risk, in so far as dogmatic assertion goes,
and the hope entertained to find in biological relations a defi-
nite guide has been realized only within indeterminate limits.
Huxley’s well accepted idea of “homotaxis” shows the un-
reasonableness of any exact inference as to simultaneity of
faunas where there are the same fossil species, and writers on
correlation have recognized the precarious virtue of an appeal
solely to identity or similarity of specific forms.

Russell (Correlation Papers; The Newark System) has
said, “‘the usefulness of the life history of the earth as a means
of correlating geological terranes is still further complicated
by a principle inherent in life itself; that is, development has

ae 4

Paleontological Speculations —Gratacap. 99

been in progress, but has not taken place uniformly over the
whole earth, but with local modifications depending upon local
environment.” White (Correlation Papers; Cretaceous) re-
iterates this in stating that “general biological evolution, while
it has been progressive, has not progressed at a uniform rate
throughout geological time, and in all parts of the world.”

A less conservative and, it would seem, more reasonable
reliance upon fossil indications is expressed by Walcott, Will-
jams, Dall and Harris. Wolcott says: “The method of cor-
relation by the comparison of fossils, or, as it has been called,
‘matching,’ is the one that affords the best results. It includes
the comparison of species, genera, families, and the general
facies of a fauna. It is the basis of paleontologic correlation
and geologic classification of the sedimentary rocks, with the
exception of the stratigraphic and lithologic correlation of lo-
cal formations ;” “all paleontologic reasoning is based upon
known data. By the discovery of a new grouping of fossils,
or a different range of known species, the identification of
horizons may be materially modified.” Dall and Harris write:
“Paleontology holds the key to the problems of local and com-
parative stratigraphy,” admitting also that there should be no
neglect of “broad and general stratigraphic changes.” Will-
iams writes: “The law of paleontologic succession did not be-
come a factor of correlation till the idea of the evolution of
species furnished a rational basis of confidence in the natural-
ness of the observed order of sequence of forms. The idea
of evolution suggests the true biologic system of correlation,
in which the data of the classification are fossils, and the dis-
tinctions made are into periods in the history of organisms,
the strata taking their relative position in the series according
to the period in this history which their contained fossil re-
mains may indicate.”

The validity of fossils as determinants of geological posi-
tion cannot be questioned, nor is it rational in our existing
knowledge to deny the correlation strictly of horizons having
the same or very similar fossils. Any possible chronological
disparity is disqualified as an objection inasmuch as such dis-
parity can be neglected, a few thousand years even, in a mat-
ter of geological contemporaneity being unimportant.

Whether such an apparently easy rule of judgment as the

100 . The American Geologist. February, 1901.

one here suggested can be advantageously or safely adopted is
a matter for discussion. Are the molar, or, it might be termed,
the molecular features of a fauna indication of comparative
age? In any case it would be merely an auxiliary consider-
ation. It might be easily misapplied and warrants in itself
no ultimate decision. But is it not helpful?

Is it reasonable upon this suggestion to place the Spergen
Hill beds, which, as Whitfield has said, “contain an interming-
ling of species known to occur in the Keokuk, St. Louis, and
Chester limestones,” below any of these from the immature
condition of size and development of these fossils? By no
means. The whole expression of the Spergen Hill fossils, as
found inthe limestone beds is one of repression. These depaup-
erate forms have resulted apparently from a peculiar fecun-
dity, or tidal concentration,which has, under some unfavor-
able conditions, produced a great number of interfering indi-
viduals. At Poynter’s Hill and at Ellettsville, at no great dis-
tance from Spegen Hill, these same beds, with fewer fossils,
show larger individuals.

But, on the other hand, it would seem reasonable to con-
clude that the western Hudson River, which as Hall long ago
observed, contains a fauna of brachiopods, with corals, crin-
oids, Crustacea and trilobites, and in the same species far more
developed than the fossils of its eastern equivalents, was later
than the New York beds of the same age.

(To be Continued.)

THE PLAN OF THE EARTH AND ITS CAUSES*

By J. W. GREGORY, D.Sc., Melbourne, Aus.
THe VARIATION OF TOPOGRAPHIC ForM.

Despite the extreme variability in the shapes of the con-
tinents and their apparently capricious distribution, geogra-
phers of all ages have believed that the arrangement of land
and water on the globe is based on a regular plan. The plan
can, of course, only be recognized in broad outline, for the
shape of the land-masses depends on the strticture of the
Earth-forms, which vary indefinitely. Intricate mountain valley

"From ‘The Geographical Journal’ for March.

The Plan of the Earth and its Causes.—Gregory. TOI

systems open out to wide-flung rolling prairie, stoneless alluvial
flats are broken by the crags of rock ridges, volcanic cones
stand isolated like pyramids while mountain chains run thou-
sands of miles unbroken. Such contrasts are natural, as the
land-forms are the result of the struggle of complex forces
with varying powers of attack against complex rock-masses
formed of materials having varying powers of resistance.
Coast-lines, for example, project where hard rocks repel the
surf, where rivers deposit alluvium more quickly than the tide
can remove it, or where the winds build up sand-dunes, whose
very weakness disarms the waves. Coast-lines are indented
where soft beds crumble under frost and rain, and where dom-
inant winds, the inset of an ocean current, or an undulation on
the sea floor directs a jet-like stream of water against the
shore. Topographical form depends on so many incalculable,
inconsistent factors that the stages of its growth are often now
untraceable. The missing links of geographical evolution are
indeed as numerous as those of organic evolution, and
the chapter of accidents is invoked by geographers to explain
difficulties analogous to those for which naturalists appealed
to the doctrine of special creation. But unexplained differ-
ences in the geographical units no more disprove an orderly
progress in the growth of the continents than the existence of
isolated, unexplained groups of animals is fatal to Darwinism.
Such topographical differences are of secondary importance
in contrast to the numerous coincidences and repetitions of
the same essential form among the geographical units. Geog-
raphers accordingly have believed that there is a hidden con-
tinental symmetry which, when discovered, will explain the
law that has determined the distribution of land and water on
the globe.

This idea dates from the dawn of geographical science.
The early classical geographers noticed how the seas radiated
from the Levantine area, and opened to a broad boundless
ocean. They accordingly described the land of the globe as an
island, floating on a vast surrounding sea, whence channels
converged towards the hub of the classical universe. This
radial plan reappears in the medizval wheel-maps, in which
Jerusalem was accepted as the center of the world, whence the
main geographical lines radiated like the spokes of a wheel.

102 The American Geologist. Webraary, 7a

These systems fell forever on the discovery of America,
which could not be brought into conformity with the radial
plan by even the ingenious devices of medizval cartographers.
Later on came an even worse blow. Geologists showed that,
instead of the land areas being fixed and immutable, they are
really more fickle and less enduring than the sea. The distri-
bution of land is therefore constantly changing, owing to local
variations in its level. The discovery of this truth seemed to
destroy the very basis of any possible Earth-plan. Indeed,
Lyellism, with its essential doctrine of the alternate elevation
and subsidence of the land under the agency of local causes,
seemed inconsistent with the existence of any general cause
governing the geographical evolution of the globe as a whole.

But a truer appreciation of this later knowledge did not
confirm these first deductions. America is now used as the
typical or, to borrow a biological phrase, the schematic contin-
ent. And when, remembering the probability of local varia-
tions in land-level, allowance is made for them, new resem-
blances are revealed, and exceptions that once were serious
difficulties are removed. For instance, the oceans all end in
triangles pointing to the north. This is the case with the Paci-
fic, the two sections of the Indian ocean, and the basins of the
Mediterranean. The. Atlantic alone is broadly open at its
northern end. But Scotland and Iceland are connected by a
submerged ridge, which is said to be capped by a line of old
moraine. If. this ridge were raised to sea-level, the Atlantic
would conform to the general rule by tapering northward to a
point between Iceland and Greenland.

Similarly with the land-masses. There seems at first sight
no resemblance in shape between the Old World and the New.
But the Old World is divided into halves by a band of lowland,
which extends southward from the Arctic ocean to the Cas-
pian, and northward from the Arabian sea up the Persian gulf.
There-is evidence to show that the sea recently covered these
northern lowlands and occupied the Persian depression ; while
somewhat earlier, in the Miocene times, the intervening ridge
was also submerged. Restore these conditions, and the conti-
nents would occur as three meridional belts, each broken
across by transverse Mediterranean seas, viz. North and
South America separated by the Caribbean depression ; Europe

The Plan of the Earth and its Causes.—Gregory. 103

and Africa (the Eurafrica of Prof. Lapworth) separated by
the Mediterranean; Asia and Australasia divided by the
Malaysian folds.

Hence the oscillating character of the land, which appeared
fatal to the old faith in an Earth-plan, helps to justify it, now
that oceanography and geology have shown us how much to

allow for the obscuring action of these changes of level.

| But it is: inadvisable, in attempting to explain the existing
plan of the Earth, to introduce any alterations in the distribu-
tion of land and water. For, although a geologist may have
no doubt about such assumed changes, he cannot expect geog-
raphers to have an equal faith in them, or even to take much
interest in a world thus modified. The geographer is con-
cerned with the existing arrangement of the world, and not
with the more or less problematical plans of former ages. The
introduction of earlier and more primitive geographical sys-
tems, though it would simplify the question, is unnecessary,
since the existence of a present Earth-plan is clearly revealed by
three striking facts.

GEOGRAPHICAL SYMMETRY.

Two of these facts are stated in every geographical text-
book. They are evident on the most casual examination of a
map. The first is the concentration of land in the northern,
and of sea in the southern hemisphere. The second is the
triangular shape of the geographical units. The continents
are triangular, with the bases to the north. The oceans are tri-
angular with the bases to the south. Accordingly the land forms
an almost complete ring round the north pole, and from this
land-ring three continents project southwards. The oceans
form a continuous ring round the south pole, and from it
three oceans project northward into the angles between the
continents. The belts of sea and land are fixed on the Earth’s
axis like a pair of cog-wheels with interlocking teeth. These
two belts may be referred to as the northern land-belt and
southern oceanic-belt.

The third striking feature in the Earth’s physiognomy is
less conspicuous, but is even more significant. It is known as
the antipodal arrangement of oceans and continents. It is
most easily recognized by examination of a globe; but it can

104 The American Geologist. ebmuary, Wa

easily be illustrated by a plain map. The antipodes of a point
in the center of the continent of North America occurs in the In-
dian ocean; and if we mark on a map the antipodes of all the
points in North America, we should find that the whole of that
continent is exactly antipodal to the Indian ocean. Similarly,
the elliptical mass of Europe and Africa is antipodal to the
central area of the Pacific ocean; the comparatively small con-
tinent Australia is antipodal to the comparatively small
basin of the North Atlantic; the South Atlantic corresponds—

FIG. I.—MAP OF THE WORLD, SHOWING THE
DISTRIBUTION OF ANTIPODAL AREAS.

though less exactly—to the eastern half of Asia; and the Arctic
ocean is precisely antipodal to the Antarctic land.

These, then, are the three fundamental facts in the existing
plan of the globe. Our main problem is, Why are the geo-
graphical elements thus shaped and thus distributed ?

THE EARTH’S CONCENTRIC SHELLS.

It simplifies the statement of the problem to remember that
the Earth consists of three parts: there is the vast unknown in-
terior, or “‘centrosphere,” concerning which physicists have not
come to any unanimous decision, some saying that it is through-
out solid and rigid, others that it is partly fluid, and others again
that it is partly gaseous. This interior mass is enclosed by a
shell formed of two layers, the solid crust, or “lithosphere,” and
the oceanic layer, or “hydrosphere.” It is possible that at
first the two layers of the shell were regular and uniform,

The Plan of the Earth and its Causes—Gregory. 105

in which case the whole world was covered by a universal
ocean; but before the dawn of geological history, this ar-
rangement had been disturbed by the formation of irregular-

ities in the surface of the lithosphere. Dry land appeared at
the areas of elevation, and the waters gathered together into
the intervening depressions.

The problem, then, of the distribution of land and water
‘on the globe is the problem of the distribution of irregularities
in the surface of the lithosphere. We are accordingly at once
brought face to face with the question, When were the existing
irregularities made? If, as many authorities say, these de-
pressions date from the earliest days of the Earth’s history,
and have lasted unchanged in position throughout geological
time, then we are thrown back upon some cause which acted
when the Earth was in its infancy. In that case the question
is astronomical and physical, instead of geological and geo-
graphical.

PRE-GEOLOGICAL GEOGRAPHY.

There have been several attempts to solve the question as-
tronomically, of which the most important is that of Prof. G.
H. Darwin. According to his luminous theory, the tidal action
of the sun on the viscous earth formed two protuberances at
opposite points of the equator ; one of the protuberances broke
away and solidified as the moon, which revolved around the
earth much nearer than at present. As a new equatorial
protuberance formed the moon pulled it backward, thus caus-
ing a series of wrinkles in the earths’ crust, which persist as
the main structural lines of the continents. These wrinkles
ran at first north and south from the equator. But owing to
the moon’s strong pull on the equatorial girdle, this part of
the earth would tend to revolve more slowly than the polar
regions. Hence the primitive wrinkles were deformed; in-
stead of being meridional in direction, they would trend north-
easterly in the northern hemisphere, and southeasterly in the
southern hemisphere. Prof. Darwin points out that some of
the most striking geographical lines on the earth run in ac-
cordance with this plan. He instances the eastern coast of
North America, the western coast of Europe, part of the coast
of China, and the southern part of South America. But, with

106 The American Geologist. February, 100%.

characteristically Darwinian frankness, he does not overpress
the facts, admits that the resemblances are not so convincing
as they might be, and that somé cases, e. g. the western coast
of North America, are absolutely inconsistent with the scheme.

Another theory that attributes the formation of the main
geographical lines to pre-geological incidents is given in a pa-
per by Prinz, “Sur les similitudes que presentent les cartes ter-
restes et Planetaires,” which elaborates and gives an astro-
nomical basis to ideas previously suggested by Lowthian
Green and Daubree. His theory is that the northern part of
the earth had a lower angular velocity than the equatorial and
southern regions. Therefore the land masses in the southern
hemisphere were gradually pushed forward towards the east.
The line between the northern retarded hemisphere and the
southern swifter hemisphere is the great line of weakness and
fracture that runs from the Caribbean along the Mediterrane-
an, down the Persian gulf and across Malayasia. Prinz has
drawn a map (Fig. 2) showing how the main geographical
lines agree with his assumed lines of torsion.

This map is interesting, for these primitve torsion wrinkles
must have been formed in the same period as Prof. Darwin’s
primitive tidal wrinkles. It is significant that the lines do not
correspond. The chief geographical lines which Darwin
claims as his primitive wrinkles are inexplicable on Prinz’s
theory, and the great lines which Prinz claims to support his
wrinkling are opposed to those of Darwin. The geographical
primitive lines of the two theories are often contradictory.

A third theory assigning the geographical distribution to
very ancient causes has been proposed by Prof. Lapworth. In
an address to the geographical section of the British Associa-
tion in 1892, and in a brilliant lecture on “The Face of the
Kwarth,” delivered to the Royal Geographical Society in 1894,
Lapworth attributed the arrangement of oceans and continents
to an intercrossing series of primitive earth-folds. The oceans,
according to this theory, occupy ancient basins of depression;
and the continental masses are domes of elevation.

“The surface of the earth-crust at the present day,” says
Lapworth, “is most simply regarded as the surface of a con-
tinuous sheet which has been warped up by two sets of undu-
lations crossing each other at right angles. . . . The one set

The Plan of the Earth and its Causes——Gregory. 107

ranges parallel with the equator, and the other ranges from
pole to pole.” Prof. Lapworth contends that the intersecting
of two simultaneous orthogonal sets of undulations explains

= -
‘

‘

FIG. 2.—THE OBLIQUE COURSE OF THE MAIN GEOGRAPHICAL
LINES. (AFTER PRINZ. )

the forms and dispositions of the continents, the triangular
shapes of their extremities, the diagonal trend of their shores,
and the course of the linear archipelagoes. In some interesting
diagrams he suggests why the intersecting nodal lines which
mark the divisions between the areas of elevation and of de-
pression should coincide with the steep slopes that separate the
ocean floors and the continental platforms; and why the exist-
ing shore lines should so often run diagonally between the me-
ridians and parallels.

This theory, and that of Sir John Lubbock, which also at-
tributes the continental forms to a double intercrossing series
of folds, have the advantage.over the astronomical theories of
more detailed agreement with geographical facts; but Prof.
Lapworth has not, so far as | am aware, explained what
caused his intersecting folds. His theory is accordingly less
complete than the others, as it is rather a statement of facts
than an explanation of causes.

108 The American Geologist. February, 1901.

These suggestive theories are open to one objection which
seems fatal to their application to the existing geographical
plan. We should expect from them that the main geographic-
al structure lines in the northern and southern hemispheres
should be either symmetrically arranged or continuous on both
sides of the equator. But that the land systems of the two
hemispheres are asymmetrical is the most glaring fact in ge-
ography. It may be urged that the primitive folding, wrink-
ling and torsion formed a symmetrical or continuous land sys-
tem, and that the asymmetrical arrangement is due to later
movements. In that case the theories are geographically in-
adequate, because they give no explanation of how the ex-
isting geographical asymmetry was developed.

But there is another and still more serious objection which
applies to all three theories. They not only explain too little
but they explain too much. The primitive lines of these systems.
often coincide with features of modern development and are in-
consistent with the old established geographical arrangements.
For instance, Prof. Darwin quotes the trend of the western
coast of Europe from Spain to Norway as in accordance with
his scheme. Prinz makes the primitive line here run exactly
at right angles to Darwin’s line; and geological evidence fa-
vors Prinz. The coast-line from Spain to Norway is almost
certainly of modern date, while the lines wrinkling, both
Hercynian and Alpine, run transversely to the direction which
they ought to have followed if due to tidal strain. Moreover,
Prof. Darwin quotes the western coast of North America as in-
consistent with his theory; but that coast is parallel to a line
of primitive wrinkling, for there is an archean protaxis to the
coast ranges and Rocky mountains.

Prinz’s torsion wrinkles are no better. The most striking
case of apparent agreement between his theory and geogra-
phy is the trend of the Andes and Rocky mountains. Prof.
Lapworth also lays stress on “‘the great Rocky Mountain-Andes
fold . . . the longest and most continuous crust-fold of the
present day.”* The agreement was important so long as the
Rocky mountains and the Andes were regarded as a single

*The term ‘‘Rocky mountains” is hereapparently used for the Sierra Nevada
and Coast Range series of British Columbia. The true Rocky mountains are
at a great distance (ranging up to 10U0 miles) from the Pacific coast, the trend
of which they do not determine.

The Plan of the Earth and its Causes.—Gregory. 109

mountain system, connected into a continuous line by a moun-
tain axis running north and south across Central America.
But that axial mountain chain in Central America is a myth.
Central America is traversed by a series of ridges which
run east and west, and not north and south.* The watershed,
it is true, runs along the Pacific border, but that is due to a
movement later than the mountain ridges which are thus trun-
cated. The continuation of the Andes is in the mountains of
Venezuela, not in North America or the Sierra Nevada. The
Andes and the mountain system of the western states of

FIG. 3—THE MOUNTAIN SYSTEM OF CENTRAL AMERICA. @, VOL-
CANIC CHAIN OF HEREDIA; Db, SIERRA CANDELLA; ¢, CORDIL-
LERA DE DOTA; d, SIERRA CHIRIQUI; @, SIERRA VERAGUA; f,
CORDILLERA DE SAN BLAS; g, VOLCANIC CHAIN OF ALAJUELA.

America are essentially distinct; they differ in every import-
ant respect, geological structure, geographical characters, and
dates of formation. Any theory which assigns the Andes and

*E.g. the Sierra Candela, Cordillera de Dota, Sierra Chiriqui, Sierra
Veragua, Cordillera de San Blas, ete.

IIO The American Geologist. ° February, 1901.

the great mountain series on the western coast of North Amer-
ica to a common origin is thereby prejudiced, instead of being
supported.

These three theories assign the earth-plan to a venerable an-
tiquity ; but there is a fourth theory, which carries it back to an
antiquity even more venerable. Lord Kelvin attributes the
oceanic and continental areas to a chemical segregation in the
gaseous nebula which was the parent of the earth. Accord-
ing to this theory, “Europe, Asia, Africa, America, Australia,
Greenland and the antarctic continent,and the Pacific, Atlantic,.
Indian and Arctic ocean depths,as we know them at present,”
were all marked out in the primzval gaseous nebula. These
gaseous continents condensed to liquid continents marked off
from the sub-oceanic areas by chemical differences; and these
liquid continents were fixed as the solid continents, hightened
by shoaling as the molten globe and its last lava ocean solid-
ified.

That theory appears probable with one verbal amendment
—the substitution of the term ‘“‘archean-blocks” for continents.
That these archean blocks—the earth’s great corner stones—
were embryonically outlined by chemical segregations in the
molten or gaseous stages of the earth seems probable. But
these archean corner stones, though the foundations of the con-
tinents, are not the continents. Lord Kelvin’s theory suggests
no explanation why chemical segregations should have as-
sumed the shapes of the continents, so that his explanation
rests on an unexplained cause; and even if his theory be
amended by application to the archean blocks instead of to the
continents, the theory is geographically insufficient, as it does
not show the relation between the archean blocks and the exist-
ing continents.

THE PERMANENCE OF CONTINENTS.

That Lord Kelvin’s nebulous segregations, Prof. Darwin’s
primitive wrinkling, Sir John Lubbock and Prof. Lapworth’s
double folds are all true causes seems probable. What is
doubtful is whether any extensive trace of their influence can
be discerned in the present distribution of land and water. A
map of the world in early Cambrian times might show the in-
fluence of these pre-geological incidents ; but their geographic-

_ The Plan of the Earth and its Causes—Gregory. Itt

al effects seem to have been obliterated by the changes of geo-
logical times.

References to such changes reminds us that we cannot as-
sume their occurrence without considering the unending con-
troversy as to the supposed permanence of oceans and conti-
nents.

There are, it must be conceded, many weighty arguments
in favor of the permanence hypothesis. Many of the last
great mountain foldings follow the lines of much older move-
ments; and if the mountain axes, the “backbones of the conti-
nents,” have occupied the same positions, why not also the con-
tinents moulded upon them? Again, some of the great moun-
tain chains, such as the Andes, run parallel to the nearest
shore-line, as if the movements that formed them had been
deflected by the ocean basin.

The character of the ocean floors, moreover, suggests that
they have never been continental, as they are at present cov-
ered by deposits not known in the interior of the continents;
and as they are supported by material much heavier than that
which forms the foundations of the continents.

These arguments, however, are not conclusive. Great
earth movements of one date often cut obliquely and trans-
versely across those of earlier periods. Thus the old north-
westerly and south-easterly movements of France and Spain
have been cut across by the east and western movements of
the Pyrenean-Alpine system. Mountain axes have not al-
ways been deflected by or limited by existing ocean basins.
Thus the north Atlantic basin cuts directly across the old
Hercynian mountain chains, which may at one time have ex-
tended across the whole Atlantic channel. This is rendered
probable by three lines of evidence. Thus in north-western
France, and in the south of the British Isles, there is a series of
ranges trending north of west, which is cut off abruptly by the
Atlantic slope. On the opposite shore of the Atlantic in New-
foundalnd, there is a similar series of truncated ranges formed
at the same age as those of western Europe, and having the
same trend. Bertrand maintains (1887) that the resemblance
between the opposite mountain series is so striking that they
should be regarded as parts of one mountain system, of which
the central part has been sunk below the Atlantic. The well-

112 The American Geologist. Webrusxy, 20h

known telegraph plateau on which the cables rest may mark the
site of this sunken land. Palzontological evidence also sup-
ports the formation of the Atlantic by subsidence; for a shal-
low water, sub-tropical, marine fauna ranged from the Med-
iterranean to the Caribbean, and can only have crossed along a
belt of shallow water in tropical or sub-tropical latitudes. Di-
rect evidence of the existence of shallow water, continental de-
posits of the age required is given by the Azores, which, al-
though now separated from Europe by a deep depression, con-
‘tain shallow water deposits with fossils of the Mediterranean
fauna.

Thus there is strong evidence to show that the Atlantic, in
its present form, is of no great geological antiquity, and Suess’
theory of its origin continually gains stronger support. Sim-
ilar, though less complete, evidence shows that the other ocean
basins have been broken up along certain lines, and emphatic-

ally denies their entire permanence throughout geological
times.

ELIE DE BEAUMONT’S “PENTAGONAL RESEAU.”

Hence, if the ocean basins were not formed pre-geological-
ly, but have grown from the changes that have occurred during
the long ages of geological time, then we must seek for a cause
that has acted continuously, and is acting today. A more per-
manent cause is supplied by the contraction of the earth’s crust,
as the globe gradually cools. Since the cold, hard crust is less
plastic than the hotter interior, it is necessarily crumpled as it is
forced into a smaller space.

This idea is well known, as it has been invoked by ge-
ologists to explain the formation of folded mountain chains.
That the mountain systems of the world were formed by this
agency is improbable; but it is perhaps still too much to say
that it is impossible. For Prof. G. H. Darwin has suggested
that the contractility of the rocky crust has been exaggerated,
and it has been shown that Reade’s level of no strain may lie
much deeper than was at first thought.

That secular contraction is the direct cause of the great
fold-mountain systems is however less widely believed by geol-
ogists than it once was; but it may have an important influence
in determining their direction. The trend of the great chains

The Plan of the Earth and its Causes.—G regory. 113

of fold-mountains is to us a significant question, because there
is much truth in the phrase, proverbial since its use in 1682 by
Burnet in his “Theory of the Earth,” which describes the
mountain chains as the “backbones of the continents.” The
first geological attempt to explain the plan of the earth was
based on this belief. The author of this system was the French
geologist Elie de Beaumont, whose theory of geomorphogeny
was stated at length in his “Notice sur les systemes de mon-
tagnes” (3 vols.: Paris, 1852). This famous theory was
based on a correlation of the mountain chains by means of their
orientation. Elie de Beaumont accepts the view that the earth
consists of a thin rigid crust surrounding a fluid, solidifying in-
terior. The crust being thin, it necessarily collapses as the in-
ternal mass contracts. He assumes that these collapses occur
at intervals of time, and that at these collapses the crust is
broken along lines of weakness, which are crumpled up into
mountain chains. He assumes that for practical purposes the
earth’s crust may be taken as homogeneous; hence that the
fractures of the crust would be regularly distributed, and those
of successive periods would cross one another along the lines
of a regular symmetrical network.

Among the regular simple geometrical forms, that known
as the pentagonal dodecahedron, which is enclosed by twelve
equal regular pentagons, possesses an exceptionable degree of
bilateral symmetry, 7. ¢. it can be cut into exactly similar halves
in an unusually large number of directions. Sections along
any of the edges of any of the pentagons and through the
center of the pentagonal dodecahedron divide it into equal
and similar halves. So also do sections from the center of
the pentagons to any of the angles, and likewise sections across
the pentagons from alternate angles. Each face of a penta-
gonal dodecahedron may therefore be divided by fifteen planes
of symmetry.

A sphere may be described upon the pentagonal dodecahe-
dron, so that all the corners (or, to use the correct term, solid
angles) occur in the surface of the sphere. By joining the cor-
ners by lines, the sphere is marked off into twelve spherical
pentagons, which possess the same amount of symmetry as the
plane pentagons. The lines where these planes of symmetry
cut the surface of the sphere form a network of spherical tri-

114 The American Geologist. Febrosty, Aa0r.

angles. Such a network Elie de Beaumont called his pentago-
nal network, and he used it in the following way. He studied
the mountain ranges of the world, and by elaborate calcula-
tions showed their relative directions at a few localities which
he chose as centres of comparison. He found that many
mountain ranges have the same orientation, and that others
cross the first set at definite regular angles. The directions
of the different sets of mountain ranges coincide with the lines
of his pentagonal network. Elie de Beaumont claimed that
the mountains whose directions are parallel,* were formed at
the same date. Successive mountain-forming movements
raised chains parallel to different edges of the network; and
thus the intersecting mountain lines of the world, and, conse-
quently, the forms of the continents, were determined.

Elie de Beaumont had no difficulty in pointing out striking
coincidences between important geographical lines and his pen-
tagonal network. Thus the Mediterranean volcanic axis, pass-
ing through the Grecian archipelago, Etna, and Teneriffe, is
parallel to the Alpine chain, and at right angles to the circle
through Etna, Vesuvius, Iceland, and the Sandwich Isles. He
was able to show a close geometrical relationship between those
lines and the line of the Andes, with the pentagon that covers
Europe. That the earth is traversed by great intersecting lines
is undeniable. E.g. Daubrée showed that the valley system of
northern France follows a line of rectangular fractures, which
he called diaclases. The directions of the Greenland fiords is
determined by a similar series of intersecting diaclastic frac-
tures. Bertrand has shown that the movements in the Paris
basin, the North sea, and English channel, have followed a
double set of orthogonal intersecting lines.

But that the fracture lines or lines of weakness in the earth’s
crust should intersect more or less rectangularly is natural on
any theory of their formation. And such coincidences as those
pointed out by Elie de Beaumont in support of his system are
inevitable in so crumpled a globe as ours; but they are not suf-
ficiently numerous to be convincing, especially in face of the
fundamental differences between the facts of geography and
Elie de Beaumont’s elaborate artificial system. His theory could

*For explanation and justification of this use of the word ‘‘parallel,’’ see
Hopkins, ‘‘Presid. Address, Geol. Soc.,’’ Quart. Jour. Geol. Soc., vol. ix. p. xxix.

The Plan of the Earth and its Causes.—Gregory. 115

only be applied to a symmetrical world ;* in a dodecahedron the
opposite faces are always similar and parallel; in Elie de Beau-
mont’s network the antipodal areas are always similar. But, as
we have seen, the fundamental fact in the plan of the world is
that opposite areas are dissimilar. In crystallographic language
the lithosphere is hemihedral, not holohedral; and no scheme
based on a holohedral form will serve. It is the recognition of
this principle that led to the next great advance.

THE TETRAHEDRAL THEORY.

Elie de Beaumont’s scheme is now mainly of historic inter-
est, though Lefort’s recent map of the Nivernais shows that it is
still used as a working hypothesis by some French geologists.
But Elie de Beaumont’s theory marked an epoch in this sub-
ject, for it led to the system of Mr. Lowthian Green, which far
better meets the requirements of the case.

This system was founded in 1875, by Mr. Lowthian Green,
in a work which was neglected or ridiculed at the time of its
appearance. Like his predecessor, Green assumes that the
earth is a spheroid based on a regular geometrical figure. He
adopted as his base the apparently hopelessly unsuitable figure
of the tetrahedron, which is contained within four equal similar
triangles. This form, with its four faces, six sharp edges and
four solid corners, does not conform to the ordinary conception
of the figure of the globe. Any comparison between them looks
ridiculous. But if we place a three-sided pyramid on each
face of the tetrahedron, its proportions are nearer those of 2
globe; and if these pyramids had elastic sides so that they could
be blown out and the faces thus made curved, then the tetrahe-
dron would become spheroidal and even spherical. Converse-
ly, if a hollow sphere be gradually exhausted of air, the ex-
ternal pressure may force in the shell at four mutually equi-
distant points, and, by the flattening of these four faces, make
it tend towards a tetrahedral form. Now the tetrahedral the-
ory does not regard the world as a regular tetrahedron with
four plane faces ; it considers that the lithosphere has been sub-
jected to a slight tetrahedral deformation, to an extent indeed
only faintly (if at all) indicated by geodetic measurements, but

*This objection applies also to yarious later modifications of Elie de Beau-
mont’s principle, such as those of Owen; or to the more than local acceptance
of the diaclases of Daubree, or orthogonal cross-folds of Bertrand.

116 The American Geologist. PeDRUEEy eee

yet easily recognizable owing to its influence on the distribution
of land and water. As the centres of the flattened faces are
nearer the earth’s center of mass than the edges, the water will
collect upon them. The ratio of the area of land to that of

FIG. 4.—RELATIONS OF A TETRAHEDRAL LITHOSPHERE TO ITS
HYDROSPHERE. FIG. 4a REPRESENTS THE ARRANGEMENT IN
A SIMPLE TETRAHEDRON. FIG. 4b ILLUSTRATES THE CASE OF
A MODIFIED TETRAHEDRON (SUCH AS SHOWN FIG. 5b) BY A
SECTION PASSING ON THE LEFT THROUGH A TETRAHEDRAL
COIGN, AND ON THE RIGHT THROUGH THE OPPOSITE TETRA-
HEDRAL FACE. THE SHADED AREAS REPRESENT WATER.

water on the globe is as 2 to 5. If ona model of a tetrahedron
we color the five-sevenths of the surface that is nearest the
centre, the colored areas would show where the water would
collect if the earth were a stationary tetrahedron. On the ‘up-
per face there is a large central colored area in the position of
the. Arctic ocean. It is surrounded by a land belt,
from which three projections run southward down the
three .lateral edges. These three land areas taper
southward to a point, below which is a complete belt
of. sea. South.of that, again, is our fourth projecting
corner, which is above the water-level, and is the Antarctic con
tinent. So that on the model the general plan of the arrange-
ment of land and water is identical with its actual distribution
on the globe. For the land occurs as three triangular equidistant
continents, united above into a ring and tapering southwards ;
there is a great excess of water in the southern and of land in
the northern hemisphere; and land and water are antipodal,
% since in a tetrahedron a corner is always opposite a flat face.

The Plan of the Earth and its Causes——Gregory. 117

But of course in the earth the faces are not flat, but are
convex. If the flat faces be replaced by projecting pyramids
with curved faces, so that the form is globular, the arrangement
of land and water remains the same, but the shore-lines are
more complex. Green has shown what the shapes of the land

a
3 5b

5c
FIG. 5.—5a, DIAGRAM OF A SIMPLE TETRAHEDRON.—5b, DIAGRAM
OF A TETRAHEDRON WITH A SIX-FACED PYRAMID WITH CON-
VEX FACES ON EACH OF THE FOUR FACES.— 5C, THE TRACE OF
THE TETRAHEDRAL EDGES ON A SPHERE; THE THICK LINES
SHOW THE POSITION OF THE TETRAHEDRAL EDGES.

and water areas would be in such a tetrahedron. The re-
semblance between his diagrammatic continent and Africa and
S. America, and between his ocean and either the Pacific, In-
dian ocean, and S. Atlantic, is very striking.

THE TETRAHEDRAL COURSE OF GEOGRAPHICAL LINES.

The agreement between the facts of geography and the
tetrahedral theory goes further. The four faces of a tetrahe-
dron meet along six edges, which should be lines of elevation
ona globe. The trace of the edges of a tetrahedron on a sur-
rounding sphere forms a circle in the northern hemisphere, and
three y~‘ic:' or meridional edges meeting at the south pole.

118 The American Geologist. Mebrusry,: 7a

In the earth the major watersheds have exactly this arrange-
ment. The great watershed of Eurasia dividing the northern
and southern drainages, runs, not along the main mountain
axis, but far to the north of it, between the parallels of 50° and
60°. The northern and southern slopes of North America are
separated by a divide along the same latitude. The southern
watersheds, instead of following the lines of highest moun-
tains, or the middle line of the continents, run close to the
coast-lines ; the three watersheds mark the three vertical tetra-
hedral edges, and they occur at almost the theoretical distances,
120° apart.

Similarly with the mountain chains. As Sir John Lubbock
has pointed out, “in the northern hemisphere we have chains of ©
mountains running east and west, the Pyrenees, Alps, Carpath-
ians, Himalayas, etc——while in the southern hemisphere the
great chains run north and south—the Andes, the African
ridge, and the grand boss which forms Australia and Tas-
mania.” That is to say, the northen mountains are parallel to
the upper edges, and the southern mountains are parallel to
the meridional edges of the tetrahedron.

THE CAUSE OF THE TETRAHEDRAL PLAN.

The statement that the elevations of the lithosphere are tet-
rahedral in arrangement is not a hypothesis, but a simple state-
ment of geographical fact. Is the fact a mere coincidence?
On the contrary, there are good reasons why the earth should
acquire such a tetrahedroid symmetry. When the earth solidi-
fied, it would (neglecting the influence of rotation) have con-
tracted into a spherical shape. It would have tended to acquire
this form because the sphere is the body which encloses the
greatest volume for a given surface. But as the earth contracts
it tends to acquire a shape in which there is a greater surface
in proportion to its bulk. Now, among the regular geometrical
figures with approximately equal axes, the tetrahedron is that
which contains the smallest volume for a given surface. Hence
every hard-shelled body which is diminishing in size, owing to
internal contraction, is constantly tending to become tetrahedral
in form. Fairburn’s experiments (quoted by Green) illustrate
this tetrahedral collapse for short tubes; and that it is consid-
ered probable by some geodists is shown by the following quo-

Review of Recent Geological Literature. 119

tation from E.D. Preston: ‘Nothing is more in accordance with
the action of physical laws than that the earth is contracting in
approximately a tetrahedral form. Given a collapsing homo-
geneous spherical envelope, it will assume that regular shape
which most readily disposes of the excess of its surface di-
mensions; or, in other words, the shape that most easily relieves
the tangential strains; for, while the sphere is of all geometric-
al bodies the one with a minimum surface for a given capacity,
‘the tetrahedron gives a maximum surface for the same condi-
tion. Experiments on iron tubes, on gas-bubbles rising in
water, and on rubber balloons, all tend to bear out the assump-
tion that a homogeneous sphere tends to contract into a tetra-

hedron.”’
(To be continued.)

REVIEW OF RECENT GEOLOGICAL
LITERATURE.

Jovellania triangularis im Miiteldevon der Eifel, von E. Kayser (Cen-
tralblatt fiir Mineralogie etc., 1900, p. 117.)
The occurrence of this well known Devonian species of Archaic in
loose fragments along with a characteristic middle Devonian fauna at
Lissengen in the Eifel is described. G. F. M.

A brief review of the titaniferous magnetites. By J. F. Kemp. (School

of Mines Quarterly, 20. 323-356; 21, 56-65.)

The known deposits of magnetic iron ore may be conveniently clas-
sified into two groups on the basis of chemical composition; the titan-
iferous and the non-titniferous. This grouping not only corresponds to
the chemical composition, but also to the geological relations and to the
present utilization and non-utilization.

Among the magnetic ores the non-titaniferous are today the only
ones mined and smelted and even their productiveness has decreased
notably in recent years, because of the great influx of cheap and easily
reduced hematites from lake Superior. The Cornwall banks in Penn-
sylvania are almost the only large American magnetite mines now in
active operation. The geological relations of the non-titaniferous ores
are variable, and, in one place and another, they have resulted from very
different originals and by strongly contrasted processes, but if titanif-
erous iron sands are omitted, the massive titaniferous ore-bodies may
be said to be closely allied in character and origin wherever they have
been studied. With one or two exceptions the titaniferous magnetites
are associated, so far as known, with rocks of the gabbro family and

120 The American Geologist. Hebrugey, Aas

furnish a distinct type of ore body, that is singularly uniform the world
over. They constitute, in most cases, large irregular masses in the
midst of intrusions of igneous rock and seem to have been produced
by the segregation of fairly pure titaniferous iron oxide, either before
or during the process of cooling and consolidation. In less common
instances the entire mass of the dike or stock is so enriched with the
iron-bearing mineral as practically to be considered an ore. Although
the ores are not at present the objects of active mining, yet the quantity
is so large and the iron afforded has such peculiar advantages of its
own, doubtless owing to certain chemical elements generally present
in the ore, that it seems improbable that they will long go without
utilization. The wall-rocks, referred to as belonging to the gabbro
family, form an extended series including anorthosyte, true gabbro,
noryte, diabase and peridotyte. To them must be added the Brazil-
ian nepheline-plagioclase rock and the nepheline-syenyte at Alno,
Sweden. In their mineralogical composition the ores involve both
ilmenite and titaniferous magnetite. The latter may be strongly mag-
neitec while high in TiO. The strong magnetism of some titaniferous
magnetite shows the improbability of removing the titanium by mag-
netic concentration. In most cases, while the iron is increased in the
concentrates by the elimination of the ferro-magnesian silicates, the
titnium is also increased. In their chemical composition the ores are
characteristic and marked. As a rule, but not invariably, phosphorus
and sulphur are notably low or entirely absent. Vanadium, chromium,
nickel and cobalt are almost always present, and they may together
amount to several per cent. Magnesia and alumina are often far in
excess of what would be required for silicates and then they are doubt-
less combined with more or less iron in spinels. Lime is of course in-
volved in the presence of the pyroxenes and related minerals and
manganese is often, but not invariably, at hand. ‘This paper consists
after the brief introduction, of summary descriptions, in geographic
sequence, of the chief deposits of titniferous magnetite now known.
The descriptions are accompanied by analyses to the number of more
than one hundred seventy which illustrate for each region the range
in composition. This work is thus a complete resumé; and the citations
place the reader in command of the literature. W. 0. C.

The Origin of Kaolin. By HetnrtcuH Ries. (Trans. Am. Ceramic

Soc., 2, Feb. 1900.)

Defines kaolin as any residual clay sufficiently free from iron to burn
to a white or nearly white color, and derives kaolin from feldspathic
minerals, in part through the agency of carbon dioxide and the ordi-
nary weathering processes (shallow deposits) and in part, as suggested
by Von Buch and Daubrée, through the agency of ascending acid vap-
ors, including chiefly hydrofluoric acid (deep deposits). Collin’s ex-
periment and analyses are cited in support of the latter explanation;
but all the economic deposits of the United States are referred to the
former. Kaolins containing undecomposed mica can not be referred to
the fluoric type. The practicability of correlating rational analyses of

oe,

Review of Recent Geological Literature. 121

kaolin with the original minerals and the method of deriviation is also
considered. W. 0. C.
Igneous Complex of Magnet Cove, Arkansas. By Henry S. WasH-

IncTON. (Bull. Geol. Soc. Am., 11, 389-416.)

This paper is an able and timely review, in the light of the mod-
ern ideas of magmatic differentiation, of the limited and isolated area
of plutonic rocks so carefully mapped and described to J. F. Wil-
liams ten years ago. The scope of the paper is clearly and tersely in-
dicated in the author’s summary, from which the reviewer quotes.
The structure of the complex is briefly described, and from the evi-

' dence of its broadly elliptical outline, relations to surrounding shales,

the presence of an overlying zone of metamorphosed rocks, the ar-
rangement and serial petrographical and chemical characters of the
main types, together with other minor points, it is shown that the
igneous complex is probably a laccolith, and certainly a unit or in-
tegral mass of intruded magma. The component abyssal types are not
due to successive injections as was suggested by Williams, but are
the products of a differentation in situ of the originally homogeneous
mass of intruded magma (“‘laccolithic differentation”. of K Gvz:r).
The main rock. types are briefly described, some new analyses being
given; and they are shown to form a regularly graded series, ranging
from. foyayte, through leucite-porphry, shonkinitic syenyte, normal
ijolyte and biotite ijolyte to jacupirangyte. This serial and common
genetic character is shown both mineralogically and chemically. It is
probable that the dikes of tinguayte and nepheline porphyry are
aschistic (undifferentiated injections of the stil! fluid differential zones
into the surrounding rocks), while those of the monchiquitic rocks are
diaschistic (products of a still farther differentiation of these zones).
The arrangement of the abyssal rocks is abnormal and differs rad-
ically from most other cases of differentiated masses, in that there is
progressive increase in acidity toward the periphery, the analagous
case at Umptek in Kola being especially mentioned. An explanation
of this is based on a process of fractional crystallization or freez-
ing of the magma, which is regarded as a solution, the solvent crystal-
lizing first, is given; and the hypothesis is applied to other cases. It is
suggested that all laccoliths and similar masses of magma may be re-
ferred to at least four different types, dependent on the chemical com-
position of the magma as a whole, the differences between which would
be satisfactorily accounted for by the hypothesis. In the opinion of the
reviewer, the explanation of this contrast between the normal centrip-
etal acidity and the abnormal centrifugal acidity of plutonic masses
might be strengthened and simplified by recognition of the important
role as a solvent of water, which, so far as known, is universally pres-
ent in magmas, and is the one important constituent which never
freezes. W. 0. C.

A Granite-Gneiss Area in Central Connecticut. By Lewis G. WeEst-
GATE. (Jour. Geol,, 7, 638-654.) ;
This is purely a petrographic paper, describing an elliptical area

122 The American Geologist. Rebrnseyy levee

of gneissoid granite on the Connecticut river east of Middletown. The
phenomena and inclusions of the inclosing schists prove the granite
to be intrusive, in spite of the marked and persistent foliation. It as-
sumes frequently the character of an “augen”-gneiss. Basic segregations
or schlieren of dark color and fine grain are a common
feature, strengthening the proof of an igneous origin, as do
the asociated dikes of pegmatyte and the contact zone of granulyte.
The component minerals, from which the chemical composition may be
approximately deduced, are chiefly quartz, various feldspars and biotite,
the feldspars including most abundantly orthoclase, with an acid plagio-
clase and subordinate microcline. The accessories include titanite and
a very little apatite and magnetite. In the granulyte garnet is the chief
or only accessory. W. 0. C.

The Origin of Nitrates in Cavern Earths. By Witt1am H. Hess.

(Jour. Geol., 8, 129-134.)

The nitrates are not derived from the excrement of bats, as pop-
ularly supposed, but have their origin in the oxidation or nitrifi-
cation of organic matter in the surface soil through the agency of
bacteria, and the subsequent leaching of the nitrates so formed down-
ward into caverns, where they slowly accumulate with other salts as
the water escapes by evaporation. This explanation is in harmony with
the fact that bats penetrate but short distances from the entrance to a
cavern, while the distribution of the nitrates is entirely without refer-
ence to the entrance, the cavern earh of the Mammoth cave having
been worked for nitrates for a distance of over five miles from the
only opening to the surface. Three analyses show that nitrates form
but a small part of the soluble salts of the cavern earth, which include
also sulphates and chlorides, and may aggregate as much as I3 per
cent. The general conclusion as to the origin and source of the
nitrates is sustained by a comparison of analyses of the soluble por-
tions of (1) subsoil from the surface above the Mammoth cave, (2)
cavern earth from the subjacent part of the cave, (3) bat guano, and
(4) cavern earth immediately below the bat guano. A comparison of
bulk analyses of bat guano and cavern earth follows; and it is sug-
gested that the calcium phosphate of the latter cannot be referred to
the former, since the insolubility of this salt makes ita necessary resid-
uary product of the solution of limestone. Analyses show that the
water dripping from the roofs of caves is not markedly different from
ordinary sub-drainage waters. The nitrates and other soluble salts
accumulate only in the earths of relatively dry caverns, or where the
inflow of water does not exceed in amount the water removed by
evaporation; and numerous analyses show that all dry caves contain
nitrous earths. Nitrates found under overhanging cliffs are of a sim-
ilar origin—evaporation of water which has percolated through the
soil; and essentially the same explanation will fit the case where
nitrates accumulate on the surface of a manure heap, through the
joint action of capillary attraction and evaporation. W. 0. C.

| The Plan of the Earth and its Causes.—Gregory. 123

Igneous Rock-Series and Mixed Rocks. By AtFrrep Harker. (Jour.

Geol., 8, 389-399.) »

A rock-series is defined as an assemblage of rock-types, with a cer-
tain community of characters, associated in the same district, belonging
to the same suite of eruptions and holding a similar position in the
scheme of igneous rocks belonging to that suite. According to the dif-
ferentiation hypothesis, they are derivatives of the same order from one
common source, resulting from differentiation along similar lines and
tc the same degree. The fundamental characteristics of such a series,

-having regard to chemical composition, are of two kinds: (1) those
belonging to the individual rock-types and shared by all the types in-
cluded in the series; and (2) those belonging to the assemblage of
types as a whole, depending upon variations in the composition of the
members as compared with one another. These characteristics admit
of very clear graphic presentation. For this purpose the method of
two equal rectangular co-ordinates first used by Iddings is recom-
mended, silica being referred to one axis and bases to the other; and
the resulting curves are briefly discussed. The origin of ingeous
rocks by admixture rather than by differentiation is next considered,
and three principal cases are distinguished: (1) mixture of two fluid
magmas; (2) permeation of a solid rock by a fluid magma; and (3)
inclusion of rock fragments in a fluid magma. The second and third
‘cases are practically limited to igneous rocks of cognate origin; and
the distinction of the included and permeated rocks or xenoliths as
accidental and cognate is regarded as important; the latter only yield-
ing by their absorption new rocks of any considerable extent or im-
portance. Several cases are considered, including the admixture of
two rocks of the same rock-series, and the solution by a magma of
extraneous quartz, and of limestone. The admixture of the extreme
types of a series will not, in general, give exactly any of the inter-
mediate types. The rock-analyses of Clarke and Hillebrand are cited
in illustration of this principle; and it is pointed out that mixtures, even
of two normal igneous rocks and still more of an igneous and a sedi-
mentary rock, must often be abnormal in chemical composition. The
relations of the chemical composition of the magma and of foreign
admixtures to the mineralogical compostion are also considered.

The Sundal Drainage System in Central Norway. By R. L. Barrett.

(Bulletin American Geographical Society, No. 3, 1900.)

The young Sundal drainage system, on the northern coast of cen-
tral Norway, possesses deep gorges and canyons which drain north-
west into the Atlantic. It is closely related to, but divided from, the
comparatively shallower and more or less disconnected valley system
of the Opdal, which drains northeast but also reaches the Atlantic.

The divide between these two systems has been shifted from east
to west, as has been the case in a less degree in the two drainage sys-
tems just south of the Sundal, the Eikedal and the Ronesdal.

The paper presents facts to prove that the divide in question once
stood near the head of the Sundal fjord, more than sixty-five kilo-

124 The American Geologist. Peprnar ys. Se

meters west of its present position, and also shows that the processes
which shifted the divide and reversed the drainage are largely responsi-
ble for the peculiar features of the Sundal system, namely, its deep
canyons and high shallow tributary valleys.

The author reconstructs the mature valley system (Opdal), de-
scribes the young canyon system, shows the relation existing between
the two and offers explanations for these relations. He discusses as
factors in the reversal of drainage: guided headward erosion by the
Sundal system and capturing of the Opdal branches, unguided head-
ward erosion and capturing, erosion by the outlets of ice-dammed lakes
which overflowed from the Opdal to the early Sundal system and
glacial erosion.

' The text is accompanied and elucidated by five diagrams which
put the whole story in clear and concise form. The paper is an ad-
mirable result of thorough investigation in the field and laboratory.

F. B.
Bulletin No. 4, of the South Dakota School of Mines, Department of

Geology. Pror. C. C. O’Harra. ,April, 19c0. Rapid City, S. Dak.

This pamphlet, containing 88 octavo pages, with several plates re-
producing old maps, furnishes an exact and very useful epitome of the
literature of the geology of the Black Hills. Many of the old papers,
now very rare, beginning with those of Dr. Prout in 1846, are an-
notated. The first portion of the bulletin sketches rapidly the pro-
gress of geological investigation in the Black Hills region, giving some
account of the parties and the routes they followed. The earliest men-
tion of the hills is in Lewis and Clarke’s report of their expedition in
1804-05-06, where they are credited with glaciers, although this must
have heen incorrect—or at least it cannot now he affirmed of the re-
gion known as the Black Hills. The author mentions fully the work
of Dr. Evans in the “bad lands,” reported by Dr. Owen in his re-
port on Iowa, Wisconsin and Minnesota, of Dr. F. V. Hayden and Mr.
F. B. Meek, Dr. Leidy, Lieut. G. K. Warren and others to 1900.

N. H. W.

MONTHLY AUTHOR'S CATALOGUE
OF AMERICAN GEOLOGICAL LITERATURE
ARRANGED ALPHABETICALLY,

Adams, F. D.
Memoir of Sir J. William Dawson. (Bull G. S. A., vol 11, pp.

550-580, 1900.)
Alden, Wm. (R. D. Salisbury and)

_ The Geography of Chicago and its environs. (Bull Geog. Soc.
Chicago, No. 1, pp. 64, plates and maps, 1899.)

Author's Catalogue. 125

Beecher, C. E.

Memoir of Othniel Charles Marsh. (Bull. G. S. A., vol. 11, pp.
§21-537, Oct., 1900.)

Beede, J. W.

Carboniferous invertebrates, (Uniy. Geol. Sur. of Kansas, vol. 6,
pp. 1-187. 22 plates. Topeka, 1900.)

Bishop, S. E.

Brevity of Tuff-Cone eruption. (Am. Geol., vol. 27, pp. 1-5, Jan.,
‘ICOt.)

Blue, Archibald

Are there diamonds in Ontario? (Rep. Bureau of Mines, 1900, pp.
119-124.)

Blue, Archibald

Report of the Bureau of Mines, 1900, pp. 230, maps and plates.
Toronto, 1900.

Brigham, A. P. ;

Glacial erosion in the Aar valley. (Bull. G. S. A., vol. 11, pp. 588-
592, 1900. Abstract and discussion.)

Calvin, S.

A notable side: from driftless area to Iowan drift. (Proc. Iowa
Acad. Sci., vol. vii., pp. 72-77, DesMoines, 1900.)

Case, E. C.

Vertebrates from the Permian bone bed of Vermilion county, IIli-
nois. (Jour. Geol., vol. 8, pp. 698-720. Nov.-Dec., 1900.)

Coleman, A. P.

Copper and [ron regions of Ontario. (Rep. Bureau of Mines, pp.
143-I9I, 1900.)

Cook, Alja R.

Memoir of Oliver Marcy. (Bull. G. S. A., vol. 11, pp. 537-542,
Oct., 1900. )

Cragin, F. W.

Goat-Antelope from the cave fauna of Pike’s peak region (Bull.
G. S. A., vol. 11, pp. 610-612, 1900.)

Crosby, W. O.

Notes on the geology of the sites of the proposed dams in the val-
leys of the Housatonic and Ten-mile rivers. (Tech. Quart., vol. 13, pp.
120-127, 1900.)

Crosby, W. O.

Geological history of the Nashua valley during the Tertiary and
Quaternary periods. (Tech. Quart., vol. 12, pp. 288-324, 1880.)
Crosby, W. O.

Outline of the geology of Long Island in its relations to the public
water supply. (Tech. Quart., vol. 13, pp. 100-119, 1900.)

Cross, Whitman

Land slides of the Rico mountains, Colodardo. (Bull. G. S. A,, vol.
II, p. 583, 1900. Abstract.)

Davis, W. M.

Continental deposits of the Rocky Mountain region. (Bull. G. S.
A., vol. 11, pp. 596-603, 1900, with discussion. )

126 The American Geologist. February, 1901.

Derby, O. A.

Mode of occurrence of topaz near Ouro Preto, Brazil. (Am. Jour.
Sci., vol. xi, pp. 25-34, Jan., 1901.)

Douglass, E.

New species of Merycochoerus in Montana, Part II. (Am. Jour.
Sci., vol. xi, pp. 73-83, Jan., 1901.)

Fairchild, H. L. ,

Proceedings of the twelfth summer meeting (G. S. A.) held at
New York City, June 26, 1900. (Bull. G. S. A., vol. 12, pp. 1-12, Nov.,
1COO. )

Fairchild, H. L.

Proceedings of the twelfth annual meeting, held at Washington, D.
C., December 27, 28, 29, and 30, 1899, including proceedings of the
first annual meeting of the Cordilleran section held at San Francisco,
December 29 and 30, 1899. (Bull. GS. A., vol. 11, pp. 511-651. pls. 51-
58, Oct., 1900.)

Faringtom, O. C.

Nature of the metallic veins of the Farmington meteorite. (Am.
Jour. Sci., vol. xi, pp. 60-62, Jan., 1901.)

Farrington, O. C.

A century of the study of Meteorites. (Pop. Sci. Month., vol. 58,
Pp. 429-434. Feb., 1001.) ‘
Gilbert, G. K. |

Memoir of Edward Orton. (Bull. G. S. A., vol. 11, pp. 542-550,
1900. )

Gordon, C. H.

Geological report on Sanilac county, Michigan. (Geol. Sur. Mich.,
vol. 7, pp. 34, 5 plates, Lansing, 1900.)
Gresley, W.S.

Possible new coal plants etc., in coal. (Am. Geol., vol. 27, pp. 6-14,
Jan., 1900.)

Hamilton, S. H.

a survey of Philadelphia. (Am. Geol., vol. 27, p. 41, Jan.
1901.

Hatcher, J. B.

The lake systems of Southern Patagonia. (Bull. Geog. Soc. Phil.,
vol. 2, pp. 139-145, Dec., 1900.)

Hitchcock, C. H.

Evidences of intergaiclal deposits in the Connecticut valley. (Ab-
stracts.) (Bull. G. S. A., vol. 12, pp. 9-10, Nov., 1900.)

Hershey, O. H.

Peneplains of the Ozark highland. (Am. Geol., vol. 27, pp. 25-41,
Jan., 1901.)

Hobbs, W. H.

A theory of origin of systems of nearly vertical faults. (Bull. G.
S. A., vol. 12, pp. 10-11. [Abstract.] Nov., 1900.)

Holmes, J. A.

Geologv and Geography at the American Association. (Science, N.
Ser., vol. 12, pp. 989-996, Dec. 28, 1900.)

Author's Catalogue. 127

Hovey, E. O.
Erosion forms in Harney peak district, South Dakota. (Bull. G.
S. A., vol. 11, pp. 581-583, 1900. Abstract.)

enn, JF.
The recalculation of the chemical analyses of rocks. (School of
Mines Quarterly, vol. 22, pp. 75-88. Nov., 1900.)

Keyes, C. R.
Formational synonymy of the Coal Measures of the western inte-
rior basin. (Proc. Iowa Acad. Sci., vol. vii, pp. 82-105, 2 plates, Des
Moines, 1900.)

Keyes, C. R.

Genesis of normal compound and normal horizontal faulting.
(Proc. Iowa Acad. Sci., vol. 7, p. 112, Des Moines, 1900.)

Keyes, C. R.

Terraces of the Nile valley. (Proc. Iowa Acad. Sci., vol. 7, pp.
111-112, Des Moines, 1900). Abstract.

Knight, W. C.

A preliminary report on the Artesian basins of Wyoming. Bull.
Wyoming Exper. Sta., No. 45, Laramie, 1900. Plates and map.
Lindgren, Waldemar

Metasomatic Processes in Fissure-veins. (Trans. Am. Inst. Min.
Eng., pp. 115, Feb., 1900.)

Merriam, John C.

Ground sloths in the California Quaternary. (Bull. G. S. A,
vol. II, pp. 612-614, 1900.)

Miiler, W. G.

On some newly discovered areas of nepheline syenyte in central
Canada. (Am. Gecl., vol. 27, pp. 21-25, Jan., 1901.)

Miller, W. G.

Minerals of Ontario, with notes. (Rep. Bureau of Mines, pp. 192-
212, 1900. )

O’Harra, C. C.

A history of the early explorations and of the progress of geolog-
ical investigation in the Black Hills region. (Bul. No. 4, S. Dak. School
of Mines, pp. 1-44. Rapid City, April, 1900.)

@Harra, C. C.

A bibliography of contributions to the geology and geography of the
Black Hills region. (Bull. No. 4, S. Dak. School of Mines, pp. 45-88.
April, 1900.)

Osborn, H. F.

Oxyaena and Patriofelis restudied as terrestrial Creodonts. (Bull.
Am. Mus. Nat. Hist., vol. 13, pp. 269-279, Dec. 21, 1900.)

Osborn, F. H.

Origin of the Mammalia 111. Occipital condyles of Reptilian
tripartite type. (Am. Nat., J4. pp. 934-047, Dec., 1900.)

Penfield, S. L.
Stereogranhic Projection and its possibilities, from a graphical
standpoint. (Am. Jour. Sci., xi, pp. 1-24, Jan., 1901.)

128 The American Geologist. February, 10901.

Purington, C. W.

A single occurrence of glaciation in Siberia. (Am. Geol., vol. 27,
pp. 45-47, Jan., 1901.)
Ruedemann, Rudolf

Hudson River beds near Albany, and their taxonomic equivalents.
(Bull. G. S. A., vol. 12. p. 11. (Abstract) Nov., 1900.)

Salisbury, R. D. (and Wm. C. Alden)

The geography of Chicago and its environs. (Bull. Geog. Soc.,
Chicago, No. 1, pp. 64, plates and maps, 1899.)
Scott, W. B.

The Mammalian fauna of the Santa Cruz beds of Patagonia
(Science, vol. 12, pp. 937-940, Dec. 21, 1900.)

Sheldon, J. W. Arms

Concretions from the Champlain clays of the Connecticut valley,
4to pp. 45, 14 plates. Boston, 1900.

Smith. J. P.
Principles of paleontologic correlation. (Jour. Geol., vol. 8, pp.
673-697, Nov.-Dec., 1900.)

Turner, H. W.

Geology of the Silver Park range, Nevada. (Bull. G. S. A., vol.
12, pp. 2-4, Nov., 1900.)
Upham, Warren

Pleistocene ice and river erosion in the St. Croix valley of Minne-
sota and Wisconsin. (Bull. G. S. A., vol. 12, pp. 13-44, Novy. 1900.)

Upham, Warren

Giant’s Kettles eroded by Moulin torrents. (Bull. G. S. A., vol.
12, pp. 25-44, Dec., 1900.)

Van Horn, Frank R.

Andesitic rocks near Silverton, Colorado. (Bull. G. A. S., vol. 12,
pp. 4-9, Nov., 1900.)

Van Hise, C. R.

Some principles controlling the deposition of ores. (Jour. Geol.,
vol. 8, pp. 730-770, Nov.-Dec., 1900.)

Washington, H. S.

_ Chemical study of the Glaucophane schists. (Am. Jour. Sci., vol.
xi, pp. 35-59, Jan., 1901.)
White, T. G.

New York Academy of Sciences. (Section of geology and mineral-
ogy. (Am. Geol., vol. 27, pp. 42-45, Jan., 1901.)

Whiteaves, J. F.

Description of a new species of Unio from the Cretaceous rocks of
the Nanaimo coal field. (Ottawa Naturalist, vol. 14, pp. 177-179, Jan.,
IQOI.)

Wilder, Frank A.

Observations in the vicinity of Wall lake. (Proc. Iowa Acad. Sci.,
vol. vii, pp. 77-82. Des Moines, 1900.) '

Personal and Scientific News. 129

PERSONAL AND SCIENTIFIC NEWS.

Dr. Otto NoRDENSKJOLD, of Upsala, is preparing a south
_polar Swedish expedition which will be ready to start prob-
ably, in the fall of 1901.

Dr. R. A. Daty of Harvard University is planning the or-
ganization of a summer excursion to Iceland, western Green-
land and Labrador, conditioned on the formation of a sufficient-
ly large party leaving Boston on or about June 26, returning
about September 20.

Proressor E. H. WILiiAms, Jr., of the department of min-
ing and geology, has equipped a geological laboratory for the
microscopic study of rocks at Lehigh University.

Prors. A. J. Moses anp L, M. LuQueEr contribute to the
Journal of Applied Microscopy abstracts of mineralogical lit-
erature, American and foreign.. These are particularly val-
uable in the mathematical and physical, especially the optical,
characters.

Pror. H. B. Parton, of the Colorado School of Mines,
Golden, Colo., offers a list of rare Colorado minerals and of
rocks, for exchange with institutions which may have others
for such disposition.

GEOLOGICAL SOCIETY OF WASHINGTON. At the meeting of
January 23rd the following was the program: “The geologic
age of Shell bluff, Ga., one of Lyell’s original localities,” T.
Wayland Vaughan; “Trias in northeastern Oregon,’ Wal-
demar Lindgren; “Comparison of the Ouachita and Arbuckle
mountain sections, Indian Territory,” J. A. Taff; “Age of
the coals at Tipton, Blair county, Pa.,”’ David White.

Tue Lake Superior Minine Institute will hold its
seventh meeting in the copper district of Michigan on March
5 to 8. The headquarters will be at Houghton.

GEOLOGICAL SociETy OF AMERICA.—The regular winter
meeting was held at Albany, N. Y., presided over by Dr. G. M.
Dawson, who gave an ex-augural address on “The Geological
record of the Rocky Mountain region.” The session con-
tinued through Dec. 27, 28 and 29, and was attended by about
thirty geologists. A large number of papers were read. A
reception was given the Society by the state geologist, Dr. F.
J. H. Morrill, at his residence, evening of Dec. 28, and the
usual subscription dinner occurred Dec. 27. The Society as-
sembled, and held its meetings, in the Albany Boys’ Acad-
emy, in the room in which Henry demonstrated publicly the
possibility of the electric telegraph. The president-elect is

130 The American Geologist. February, 100%

C. D. Walcott. The next winter meeting is planned to occur
in Chicago.

GEOLOGICAL SOCIETY OF AMERICA, CORDILLERAN SECTION—
The.western, or as it is called the Cordilleran section of the
Geological Society of America, was established by a few of
the geologists of the western coast whose distance precludes
them from joining their fellow members of the eastern part
of, the continent, save on rare occasions. The second annual
meeting of this section was held on Friday and Saturday, the
28th. and 29th of December, at the State University of Cali-
fornia, at Berkeley. Prof. W. P. Blake, of the University of
Arizona, presided on the former day and Prof. W. C. Knight,
of Laramie, Wyoming, on the latter.

The first meeting was held in the council room of the
California Academy of Science at San Francisco, and the
other at the state university, Berkeley, where all arrangements
for the convenience of visitors had been made by the secretary
and other resident members. Prof. Andrew Lawson, of
Berkeley, secretary of the section, was also the secretary. of
the meeting.

The following summary will show the course and scope

of the proceedings:
Prof. Blake read the first paper, and in it he gave the evidence for

the existence of any ancient, probably Cambrian, sandstones and quartz-
ytes, on the granite of Arizona. He also mentioned the existence of
limestone with Atrypa reticularis and of quartzytes with Devonian
fossils. In the Santa Catarina mountains are uncrumpled strata, prob-
ably the equivalents of the Huronian and Laurentian of Canada, and
also much crumpled beds of mica-slate standing nearly vertical.

Reference was also made to beds of pegmatyte and in the discussion
that followed to very thick strata of Cambrian dolomytes with strata
of quartzytes penetrated by intrusive granites of Cambrian date. The
paper was followed by considerable discussion, in which most of those
present took part.

Prof. E. W. Claypole, of Pasadena, next spoke of the structure
of the Sierra Madre and the valley of Pasadena. This range is ap-
parently a continuation of the ranges of the Santa Lucia and the
San Rafael mountains, and consists of two materials. The front or
southern face is composed of a very highly hornblendic granite which
by the oxydation of iron is subject to rather rapid and deep weather-
ing. Corrosion is consequently severe and the existence of crags and
cliffs is rendered difficult. Behind this and forming the higher portion
is a white felspathic gneiss containing very little hornblende and
weathering less rapidly. Of this consist the crags and scarps so con-
spicuous from the valley. The valley is almost entirely made up of
detrital material derived from the destruction of the Sierra—often
many hundreds of feet deep and consisting of strata of gravel and
clay. These form the great water-storage of the region and during

Personal and, Scientific News. £31

the past dry season they have been exploited. in:.theyseanch:.for..water
and have proved vastly more productive than had been preyiously
believed. The possibility of largely inéreasing, the. produ¢tiveness of
the valley of Pasadena and the plain of Los Angeles has, consequently
been rendered almost a certainty. The paper. concluded .with a, few
notes on the method now in course of adoption. for. further Jncreasing
and storing the rainfall.

On Friday afternoon Prof. E. W. Hikes cd, Be the series de-

partment of the University of California, spoke onthe soils.of the state

and the mode of their formation, the power of, kaolinization,, the effect
of wind and the origin of adobe. He pointed out the difference , be-
tween the soils of the dry and the humid regions, maintained that few
of them needed “liming” or, as it is called, “marling,’” as there is, usu-
ally present from 1 to 2 per cent of lime in some form or other, a
large part of which is the carbonate. He showed that most of these
aluminous soils retain the potash resulting from the decomposition
of the orthoclase and that in many cases this, in the soil of the. sur-
face alone, amounts to 1200 to 1800 pounds per acre.

Much of the sandy soil of the state needs only water to become
abundantly fertile, if tolerably free from alkali (chiefly carbonate of
soda) and the dryness of the superficial soil forces the roots to pene-
trate it to a much greater depth than roots do in moister regions. In
consequence of this fact crops which there would be killed by a long
drought are here able to survive and even flourish for months without
any rain.

F, M. Anderson, of Berkeley, described the river system of north-
ern California and the Klamath mountains. The latter, he-said, contain
two sets of flexures at nearly right angles to each others. but not co-
eval. The streams have the level intermontane areas, in many cases,
by narrow canyons, indicating an immature topography. Deposits of
Chico, or Upper Cretaceous, age occur on the north. ,and south. sides
of the Siskiyou river, shaly below and conglomeratic above. .

The lavas of the Cascade mountains are of different ages; the
oldest eruptive are certainly of a date before the deposition of the
Chico, or Upper Cretaceous, beds and between them and the later beds
lie the Ione deposits. Near the head of the Siskiyou river there are
indications of four distinct periods of volcanic activity... In some of
the tuffs are petrified fragments of wood and under some. of the
andesitic beds are specimens of unmineralized wood, : black and
scorched. This and the drainage of the region which is antecedent in-
dicate the very recent date of the eruption.

H. W. Fairbanks, of Berkeley, spoke on a group. of a et peaks
called “The Three Sisters” in central Oregon... They. rise. to. a’ hight
of 10,000 feet, and among them lies a glacier nearly three miles. long
and half a mile wide. The paper was illustrated by a number of slides,
showing the mountain and the topography of the region: The recency
of volcanic activity is proved by the superposition of the lava on glaci-
ated surfaces of the rock and by the presence of a small volcanic cone in

132 The American Geologist. Pebrapry, 220%

the path of the glacier which has not been able to destroy or seriously
erode it.

Prof. A. C. Lawson presented a series of arguments drawn from
the superficial structure of the region tending to show that the-elevation
of the Sierra Nevada was in date later than that of the Coast ranges. He
argued that the river-valleys of the two regions presented marked dif-
ferences—that the drainage in the Sierra Nevada is consequent and
the system therefore immature, while in the Coast range the drainage
is subsequent and the geomorphy mature. Illustrations were drawn
from the branches of the Klamath, Eel and Sacramento rivers in sup-
port of the views advocated in the paper.

Prof. Lawson also spoke briefly on a specimen of feldspar-bearing
corundum, from Plumas county, California, which occurs as a dyke
cutting serpentine on the eastern flank of Spanish peak. He spoke of
the rocks as supersaturated with alumina, and said, the feldspar was
an oligoclase containing by an analysis 16 per cent of corundum.

Prof. J. C. Merriam, of Berkeley, spoke of the John Day beds ex-
posed on the river of the same name. The canyon is cut through an
immense series of strata about 10,000 feet in thickness and ranging
from the Jurassic to the Quaternary and composed of nine or ten dis-
tinct beds. These include large quantities of volcanic tuffs and ashes,
with andesitic and rhyolitic lavas lying on the John Day beds and
tilted with them to an angle of 30° over which are seen 1,500 feet of
Columbian lavas. The abundance of land shells of such genera as
Helix, the scattering of the bones of the skeletons and the absence of
fish remains were mentioned as tending to cast some doubt on the
lacustrine nature of the deposit. Ten skeletons have been found whole
and very few, plant remains occur. The Cretaceous beds are of the age
of the lower Chico.

Mr. H. M. Turner, of Washington, D. C., spoke on the Geology of
the Great Basin in California and Nevada. The address was illustrated
with lantern slides. The ridges of the western edge of the Great
Basin in Nevada and eastern California, are usually very complex in
structure and composition. They comprise sediments of Paleozoic
and Juratrias age much disturbed at some points by intrusions of
granolytes. In Tertiary time there were extensive lakes, and con-
temporaneous with these lakes, and also later, lavas and _ tuffs
in large amount, chiefly rhyolytes, andesytes and basalts. The for-
mation of the ranges or at least their latest uplifts date from the
Tertiary or post-Tertiary. They were elevated along normal faults,
the valleys being subsided areas, often of the nature of rock basins,
whose rims are made up of rocks older than the desert detritus.

There are some gneisses pretty certainly of pre-Cambrian age.
These gneisses underlie lower Cambrian slates and limestone There
is an extensive chert series rich in graptolites supposed to be of lower
Silurian age. There are also lower Trias beds in the Inyo range and in
the Pilot mountains’ Jurassic limestone and slate. The Tertiary lava
beds contain abundant plant, molluscan and fish remains.

THE AMERICAN GEOLOGIST, VOL. X XVII.

Sepa

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SHOWING THE DISTRIBUTION
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TRAP DIKES

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TAP OF THE CRYSTALLINE AREA OF NORTH Groroia, SHOWING THE

0 J 10 18 20

DISTRIBUTION OF TRAP ROCK,

XII,

OF THE CRYSTALLINE AREA

THE AMERICAN GEOLOGIST Puace XIL.

MAP

“THE CRYSTALLINE AREA
OF GEORGIA

SHOWING THE DISTRIBUTION
OF

TRAP DIKES

BY
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a ae a TRAP DIKES

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UNIVERSITY of ILLINOIS,

PLATE XIII.

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VOL.

EOLOGIST,

*
x

THE AMERICAN (

EXpPosuRE OF A TRAP DIKE ON THE CENTRAL RAILWAY, Four MILES EAST OF NEWMAN, COWETA COUNTY, Ga.

THE AMERICAN GEOLOGIST, VoL. X XVII. PLATE XIV,

THIN SECTION OF OLIVINE DIABASE, FIVE MILES NORTH OF MACON, Ga., AS IT

APPEARS UNDER CROSSED NICOLS X 75.

\ ents Pe Re
Vater

THE
Peer AN GEOLOGIST.
Voi. XXVII. MARCH, 1gol. No. 3.

SOME NOTES ON THE TRAP DIKES OF GEORGIA.
By S. W. MCCALLIE, Atlanta, Ga,
Plates XII-XIV.

The trap dikes of Georgia are confined to what is known as
the Crystalline area, an old land surface, occupying the central
and northern part of the state. This area is made up largely
of schists and gneisses with numerous intrusive bosses of
granite. The schists and gneisses occur chiefly in alternate
bands or zones having a northeast-southwest trend. The
dikes are pretty evenly distributed throughout the area and
are found mostly in groups which consist of one large, or
mother dike, paralleled on one or both sides by smaller dikes.

The larger dikes often attain a maximum width of 200
feet and sometimes extend for many miles with but few in-
terruptions. A good example of one of the larger dikes is
to be seen in a cut on the Central railroad, a few miles east of
Newnan in Coweta county. This dike continues for about
sixty-five miles in a southern direction through Coweta, Meri-
wether and Talbot counties, finally disappearing beneath the
Columbia sands some four miles south of Talbotton. Within
this distance there occur a few breaks or interruptions a mile
or more in length due either to an actual discontinuity of the
dike or its burial beneath the residual products derived from
the enclosing schists.

The smaller dikes vary from an inch to a yard or more in
width and never continue for more than a few hundred rods.
In some localities these smaller dikes are quite numerous. On
the Georgia railroad near Covington as many as seven of these
dikes are to be seen within a short distance of each other. The

134 The American Geologist. MNEs ee

dikes as a general rule all have a vertical dip, and a northwest-
southeast trend, thereby invariably cutting the gneisses and
schists at a considerable angle. In some instances the large
dikes, owing to their slow weathering, have given rise to low,
flat ridges whose sides are usually strewn with innumerable
rounded bowlders, locally called “nigger-heads.”

All of the trap dikes throughout the Crystalline area ap-
pear to be of the same age and are formed of similar rock ma-
terial. They are evidently of a comparatively recent geolog-
ical age as is shown by their undisturbed condition. They
rarely ever reveal any evidence of shearing or any other in-
dication of a general earth movement. Along the southern
margin of the Crystalline area between Macon and Muilledge-
ville at a point on the Georgia railroad, near James’ Station,
a dike comes in contact with clay beds which have been classed
by Dr. Geo. E. Ladd as Tertiary beds.* The exposure here,
however, is limited and gives no satisfactory evidence as to the
relation of the dike to the Tertiary clays. A further study oi
the dikes along the above contact will probably demonstrate
that they are of Jura-Trias age, and belong to the same system
as the trap dikes of the Carolinas and Virginia.

The rocks of the dikes are quite compact, fine-grained and
of a dark-gray, or almost black color. They are typical dia-
bases made up of plagioclase and augite with olivine and mag-
netite as the chief accessory minerals. The plagioclase occurs
in the form of long, slender, lath-shaped crystals, which are
frequently enveloped in large irregular plates of augite, thus
exhibiting a beautiful ophitic structure.

THE PLAN OF THE EARTH AND ITS CAUSES
By J. W. GREGORY, D.Sc., Melbourne, Aus.
* (Continued from p. 119.)
THE EARTH A GEOID.

But it may be said this tetrahedral theory is impossible, be-
cause we know from our elementary text-books that the earth
is not terahedral, but is an oblate-spheroid—that is to say, a
sphere slightly flattened at the poles.

The oblate spheroid is no doubt the form that rotation
would have caused the earth to assume as it solidified, if the

* The American Geologist, vol. xxxiii, pp. 248.

The Plan of the Earth and its Causes—Gregory. 135

earth were quite homogeneous. But the earth is not homo-
genous; it varies in strength and density, and an unequal load
on the earth in any area leads to a divergence there from the
circular shape. It is, I believe, now universally admitted that
the earth is flattened laterally at the equator as well as at the
poles. The question was long disputed between the astrono-
mers, who, from theoretical considerations, declared what the
shape of the world ought to be, and the geographers, whose
measurements showed what the shape actually was. There is
now a general agreement that the geographers were right; that
the equatorial section of the earth is elliptical, similar to a sec-
tion through the earth passing across the poles. The earth is
therefore not a true spheroid, and it was accordingly regarded
as an ellipsoid with three unequal axes. But there is good rea-
son to believe that the earth is not even an ellipsoid; for the
northern and southern hemispheres are unlike, and the earth
is therefore shaped like a peg-top. This is shown in two ways.
It is a well known property of the ellipse that degrees meas-
ured along the flatter side are longer than degrees measured
near the sharper end. It was by proving that a, degree of lat-
itude in Lapland is longer than a degree of latitude in Ecuador
that the French astronomers in the seventeenth century defi-
nitely proved the earth’s flattening at the poles. In continua-
tion of these observations, La Caille, in 1751, measuréd the
length of a degree at the Cape of Good Hope. His measure-
ments showed that the southern hemisphere was also flattened,
but to a different extent than the northern hemisphere. This
anomalous result of La Caille’s was confirmed and extended by
Maclear.

The inequality of the two hemispheres has also been shown
by the variations of gravity in the two hemispheres, which, as it
is more easily tested, has been more widely applied. The prin-
ciple is simple. A pendulum swings more rapidly the nearer
it is brought to the centre of the earth. A pendulum swings
more slowly on a mountain-top than at sea-level. It was be-
cause Richer, in 1672, found that a clock which kept correct
time at Paris lost two minutes a day in French Guiana that the
polar flattening was first suspected. So many observations
have been made that maps have been compiled showing the va-
riation of the force of gravity throughout the globe. Fig. 6 is a

130 The American Geologist. March, 1901.

100 120 40

gaeescae
ear ke
roe

Los {
Si ee anes
| Saree

i
Si

am
=
a

X-a

FIG. 6.—STEINHAUSER’S MAP, SHOWING VARIATION IN ATTRAC-
TION OF GRAVITY, AS INDICATED BY LENGTH OF THE SECOND-
BEATING PENDULUM. O = LENGTH IN EQUATORIAL BELT;
I-5—NOS. OF MILLIMETRES BY WHICH A PENDULUM HAS TO
BE LENGTHENED IN’ ORDER TO BEAT SECONDS AT DIFFERENT
LATITUDES.

copy of Steinhauser’s map, in which the variation of gravity is
illustrated by showing how many millimetres have to be added
to the length of the pendulum which beats seconds at the equa-
tor, to make it vibrate at the same rate elsewhere. In both
northern and southern hemispheres the second-beating pendu-
lum has to be steadily lengthened as we approach the poles, but
the deviation is at a different rate for the two hemispheres.
The surface of the southern hemisphere does not approach the
earth’s centre of mass at the same rate as the northern hemis-
phere. If the earth’s centre of mass is at its geometrical
centre, then the earth’s form is elongated southward like a peg-
top. It is often held that the earth’s centre of mass is to the
south of its center of form, because of the accumulation of
water in the southern hemisphere. It is held that the water is
piled up there, owing to the greater density of the southern

a gh

The Plan of the Earth and its Causes.—Gregory. 137

hemisphere. If that be the case, then the peg-top elongation
is all the greater.

Morevoer, there is evidence to show that the earth’s figure is
still more irregular than that of a peg-top.* Sir John Her-
schel, although taking the astronomical side in the controversy,
aptly stated the facts in the statement that ‘‘ the earth is earth-
shaped.” Listing’s name of geoid, which expresses this view,
has now supplanted the old oblate spheroid from everything
except the text-books. That there are local deformations in
the earth’s shape is demonstrated by the differences between
the astronomical and trigonometrical determination of posi-
tions. Places have two different longitudes, the astronomical
longitude obtained by astronomical observations, and geodetic
longitudes determined by terrestrial measurements ; the differ-
ences are often considerable. It was calculated, e¢.g., that the
trigonometrical and astronomical determinations of the sta-
tions used in the delimination of the Canadian and United States
frontier should have agreed within 4o feet, or 0.4 of a second
of arc; but the average error was more than five times as great,
and ran up to eighteen times as much as it should have been.

Astronomical determinations, moreover, are often not only
inconsistent with geographical measurements, but they are
often inconsistent with themselves. For example, one of the
most refined estimations of longitude that have yet been at-
tempted, is the series undertaken by the “KK. K. topographische-
militar Institut’ of Vienna. To ensure. accuracy during these
observations, the most elaborate precautions were taken. Cor-
rections were even made for the effect of the doses of quinine
which the astronomrrs took when working in malarial cli-
mates. In one of the series of observations, the difference in
longitude between Vienna and Milan was determined first di-
rectly, and then by determining the difference between Vienna
and Brescia and that between Brescia and Milan. But in spite
of all the care, the results did not tally. The sum of the two
differences was not the same as the single difference. The
whole, in fact, in this case was less than the sum of its parts.

To astronomers it may seem an unnecessary waste of time
to devote so much to proving these deformations from the
“spheroid of reference.” But as the idea is less familiar to

* As Prof. Darwin suggests, potato-shaped would be a more correct simile.

138 The American Geologist. Moreh,

geographers and geologists, the insistence on this deformation
may not be useless. It may be worth while adding a quotation
from Prof. C. A. Young,* to show that the spheroid of refer-
ence is only a convenient assumption. ‘On the whole,” says
Prof. Young, “astronomers are disposed to take the ground
that since no regular geometrical solid whatsoever can absolute-
ly represent the form of the earth, we may as well assume a
regular spheroid for the standard surface, and consider all var-
iations from it as local phenomena, like hills and valleys.”

As deviations from the assumed spheroid of reference exist,
it remains to inquire whether there is any evidence that they
agree in position and arrangement with the theory of the tetra-
hedral deformation of the lithosphere.

The evidence already quoted of the dissimilarity between
the northern and southern hemispheres and the elongation of
the latter, is geodetic proof of the northern flattening and the
antarctic projection, 7. e., of one face and one tetrahedral cor-
ner.

The three flattened lateral faces and three projecting verti-
cal edges are sufficiently demonstrated by the three great
oceans and the land-lines that have divided them. Practically,
all the theories agree upon that point. Jt is well known that
gravity is greater than was expected at most oceanic islands.
Lallemand and de Lapparent have suggested that this is due to
those islands being below the level of the ordinarily accepted
figure of the earth, and therefore nearer the earth’s centre of
gravity.t Fisher has suggested that the Pacific ocean is the
hollow left by the loss of the material which forms the moon.
Faye has explained the ocean basins and the greater density
of the crust below them as due to more rapid refrigeration
below the cold oceanic abysses. According, therefore, to Faye,
the rocks below the oceans contracted more than those below
the continents, became denser, and accordingly sank.

Thus from all points of view the three oceans represent
areas of depression, and the three land-lines of South America,
Africa, and Australia mark intervening projections. The
oceans mark the low areas in the lithosphere as obviously as

*iCGrA: Youne, General Astronomy,’ p.101. 1889.

} This explanation is inadequate, as it does not explain the deviation of
the pendulum on coast-lines towards the ocean. The excess vertical attraction
of the islands has been explained as due to the attraction of the mass of the
island and its base.

The Plan of the Earth and its Causes—Gregory. 139

the bubble of a spirit-level marks its higher end; and they give,
therefore, evidence of the triangular lateral flattening of the
southern half of the globe.

But as, on the mathematical figure of the earth, such lateral
flattening is more improbable than variations along the axis
of rotation, let us consider whether there is any geodetic proof
of these flattened faces and projecting edges.

There has been a long controversy as to whether Bessel’s or
Clark’s ellipsoid better represents the figure of the earth.
Clark’s figure was the later in date, and is generally considered
as the more exact. Helmert therefore expresses some surprise
that the gravitational observations in central Europe along the
52d parallel of north latitude agree with Bessel’s curve better
than they do with Clark’s; this is the case all across the area
on which Bessel’s work was done. But as soon as we get into
the Volga basin, the gravity line diverges from Bessel’s curve
and approaches that of Clark. The change comes due north
of the Eurafrican meridional edge. The anomalies are at
once removed if we assume that both ellipsoids are locally cor-
rect; that Bessel’s curve is true for Europe, and Clark’s cor-
rect for Asia; and that the two merge into one another north
of the line of the Eurafrican tetrahedral edge.

On the tetrahedral theory, there ought to be a projection
north of this tetrahedral edge. And gravity determinations
show a great deficiency in gravity in western Russia in an ap-
propriate area along the Volga basin. It is true that the fig-
ures have been queried. There is a natural tendency to query
all facts that do not agree with theory, and the notes of interro-
gation in this case may illustrate that tendency. But on the
view that there is an upward deformation of the earth in this
area, the anomalous deficiency in gravity observations is at
once explained.

It may be replied that the existence of a normal gravity at-
traction at Moscow negatives the assumption of a superficial
deformation ; but the relative excess of attraction there is pos-
sibly due to the outcrop of Paleozoic rocks, of greater density
than the loose sediments of the Russian lowlands.

Passing from Russia to the area in North America, where
the next tetrahedral corner ‘should occur, there is another area
of deficient gravity, which may also be due to that area being a

140 The American Geologist. Maree

tetrahedral elevation. The deficiency is explained by the as-
sumption of vast subterranean blocks of very light material.
But that explanation is prohibited in the Russian case, since,
as Helmert has shown, the deviations of a plumb-line from the
vertical are inconsistent with the existence of such blocks. In
reference to the North American case, Helmert has remarked
that the light subterranean blocks must have descended for sev-
eral kilometres; and Mildenhall has shown that no reasonable
assumption will suffice to explain the facts.

It would be too much to claim that geodetical evidence at
present available proves the tetrahedral theory, for accurate
data are not yet available for a sufficient proportion of the
earth to show whether the major deviations are based on a
regular plan; but papers, such as that of Mr. E. D. Preston,
show that geodesists are more inclined to regard the theory
with favor. It is at least clear that geodesy does not disprove
the hypothesis, and that some puzzling geodetic anomalies re-
ceive a simple solution if the theory be true.

GEOLOGY AND THE TETRAHEDRAL COIGNS AND EDGES.

Let us now turn to geology, to see if its evidence as to the
past history of the world refutes or supports the theory.

The geological evidence ought to be of especial value, as
we should expect to determine the position of the tetrahedral
coigns on the face of the earth.*

If the tetrahedral theory be true, the four tetrahedral coigns
should be areas of unusual stability and strength. Comparison
of the three meridional land-belts shows that each of them be-
gins in the north with a vast block of Archean rocks. The Eu-
rafrican zone, in longitude 20° E, begins with a block occupy-
ing Scandinavia, Finland, and Lapland, which Suess _ has
termed the “Scandinavian schild.” It is an area of great ge-
ological antiquity, which has long remained above sea-level;
bands of marine deposits of different ages sweep round it, but
the block may never have been below sea-level. It has un-
questionably remained as a solid impassive block, which has
dominated the whole geological history of northern Europe.
South of the Scandinavian coign are the transverse east and
western chains of the Alps and the Atlas, with the Mediterran-

* They were assigned to their geometrical positions by Green, and in the
nteresting recent tetrahedral volcanic map of M. Michel-Levy.

The Plan of the Earth and its Causes—Gregory. 141

ean trough between; and far to the south we have the old
plateau of South Africa.

Let us now go 120° westward to the American zone. It
begins with another block of old Archean rocks, forming what
Suess has called the “Canadian schild.”” It occupies Canada,
Labrador, and most of Hudson bay and Baffin’s Land, and un-
‘derlies Greenland. Bands of marine deposits surround it, but
it has perhaps never been itself below sealevel; its geological
age, at any rate, is enormous. South of the North American
coign we have again a pair of east-west mountain chains, form-
ing the highlands of Cuba and Venezuela, separated by the
Caribbean trough. This zone also ends southwards in an old
plateau resting on Archean rocks.

The third meridional zone repeats the same characters. It
begins with a block of Archean rocks, of which we may speak
as the “Manchurian coign.”’ South of this coign are the east
and west ridges of Malaysia and the depressions parallel to
them; and south of that, again, we have the Archean plateau
of Australia.

The three main land axes of the world have remarkable
resemblances in structure, and they present three equidistant
blocks of great stability at the three tetrahedral corners. We
may, therefore, speak of the “‘schild” as the three northern
coigns or corner-stones of the earth.

The existence of these massive coigns* at the three tetra-
hedral corners has produced one point of divergence in the
earth-plan from the geometrical figure of the tetrahedron. The
existence of three such broad massive blocks naturally
strengthens the line between them; and, as we have seen, the
main divide in the northern hemisphere runs from coign to
coign. The tetrahedral edges would naturally be lines of weak-
ness and of movement; but in the northern hemisphere, the
horizontal lines of yielding are deflected southward by the
stability of the band supported by the earth’s three northern
coigns. Hence the great band of disturbances is subtropical,
and runs from the Caribbean to the Mediterranean, across the
Persian gulf and the Malaysian archipelago.

* This suggestion of the word ‘‘coign’’ for ‘‘corner’’ I owe to Mr. L. Fletch-
er, to whom I am indebted for much helpful advice. The term is suitable, as it
is used for a printer’s wedge as well as for the corner-stone of a house.

142 The American Geologist. March, 1001.

In the case of the vertical edges, however, the agreement
in position, as well as direction, is exact. Precisely below the
three corner blocks, there are three lines of instability coincid-
ing with the vertical tetrahedral edges. Below the Canadian
coign there is the line of the Andes (long. 75°), which, accord-
ing to some geologists is still undergoing elevation. Almost 120°
east of the Andes, and below the Scandinavian coign, is the
Erythrean rift-valley (mean long. 40°), in which some of the
earth-movements are unquestionably of very recent date.
Again, nearly 120° eastward, and due south of the Manchurian
coign, is the recent line of movement represented by the east-
ern coast of Australia.

The main mountain systems of the world correspond, then,
in direction or position, or in both, with the edges of the tetra-
hedron. The mountain lines run east and west in the northern
hemisphere, and run meridionally in the southern hemisphere
—that is, always parallel to the tetrahedral edges.

But it will be said there are three great exceptions, for the
Ural mountains, the Appalachians, and the Rocky mountains

are meridional instead of transverse, and that they therefore .

contradict the scheme. The contradiction is only apparent.
The existing mountain ranges date from two main periods of
mountain-building—the Upper Cainozoic and the Upper Palz-
ozoic. The Upper Tertiary system includes the Alps, Andes,
Himalaya, Pyrenees, Caucasus, and Atlas, etc. The Urals,
Rocky mountains, and Appalachians belong to the Upper
Paleozoic system. Before we can say whether these chains
confirm or refute the tetrahedral theory, we must determine
the distribution of land and water at the time when they were
made.

Now, we know that in upperPalzozoic times one land fauna
and flora ranged round the southern hemisphere from Austra-
lia to India, and thence to the Cape and South America. In-
stead of there having then been a continuous ocean-belt sep-
arating triangular points of land, there was then a southern
land-belt, which was supported by three great equidistant cor-
ner-stones, the Archean blocks of South Africa, of Australia,
and of Patagonia and the Patagonian platform.

What the south pole was doing then is hidden by our de-
plorable ignorance of that area; but there is evidence that to

-. «>. eee

The Plan of the Earth and its Causes.—Gregory. 143

the south of this southern land-belt there was a cold, ice-laden
sea. |

Now let us consider the state of affairs in the arctic regions
at the same period. At the present time the Mollusca of the
Behring sea and North Atlantic belong to two essentially dis-
tinct faunas. But in upper Palzozoic-Triassic times, one fauna
occupied both regions, and that fauna moreover extended un-
interruptedly round the northern hemisphere, and apparently,
along certain lines, extended some distance to the south. There
was, in fact, a northern ocean-belt, which apparently sur-
rounded a cold arctic land. The distribution of the land and
water was then on the same plan as at present, but with land
and water exactly reversed. There were two opposite inter-
locking belts of land and sea, the former based on three Arche-
an corner-stones, the latter projecting toward the equator be-
tween three Archean plateaux.

Thus the plan was the same as at present, but the condi-
tions were reversed. This gives us the clue to the mountain
chains of the same period. That also was a double system.
There was a sub-tropical mountain girdle, the ruins of which
we can trace right across the old world from eastern China
to western Europe, where it is cut off by the Atlantic slope.
And projecting meridionally from that equatorial girdle, op-
posite the three coigns, we have three mountain ranges run-
ning along the meridional edges. These are the Ural moun-
tains (60° E.) north of the eastern continuation of the South
African coign, the Appalachians (80° W.) north of the west-
ern part of the old Patagonian coign, and the old broken axis
of Kamtschatka (160° E.) north of the coign of Australasia.

DEFORMATION AND RECOVERY.

Such a change in the position of the flattened faces is by
no means improbable in the case of a revolving globe. In the
case of a stationary body, a tetrahedral deformation once be-
gun would be strengthened by every fresh contraction. But
owing to the world’s rotation, the tetrahedral collapse is stead-
ily resisted, and confined within narrow limits. The deform-
ation formed by one period of slow, quiet contraction may he
lost on the restoration of equilibrium at an epoch of great
crustal disturbance. When deformation begins again in con-

144 The American Geologist. March, Si

sequence of renewed contraction, the flattening may occur
elsewhere.

This hypothesis of the alternation of periods of deformation
with periods of spheroidal recovery is geologically useful, as
it suggests an explanation of a certain periodicity in geolog-
ical phenomena. For instance, the later half of Palzeozoic time
may have been a time of slow tetrahedral collapse, culminat-
ing in an instability which led to the great mountain move-
ments which closed the Paleozoic ; then followed a quiet period
of slow restoration of the spheroidal form, causing the series
of marine “transgressions” which are the dominant feature of
the geological history of the Mesozoic era.

VERTICAL RANGE OF DEFORMATION.

Reluctance to admit the possibility of such changes is re-
duced when we recollect how insignificant ‘are the differences
in level, when compared with the size of the earth. The use
of exaggerated diagrams leads to unconscious magnification of
the extent of the polar flattening, and of the difference between
the continental summits and the oceanic depths. The study of
large-scale maps has been authoritatively recommended. The
examination of true scale curves and outlines may help us to
realize the actual conditions. The accompanying figure* shows
a section of the earth’s crust from Stromboli to Vesuvius. The
thick black band represents the section cross the Mediter-
ranean ; the line ab marks the depth of the Atlantic; the upper
curve shows where the surface would be if there were no polar
flattening. The lowest line marks the depth of one-hundredth
of the earth’s radius. The thickness of this zone in compar-
ison with the size of the earth is shown on Fig. 7, b, which is a
sector of a circle, with the zone of a shown, reduced to its true
relative size. The polar flattening is barely recognizable, and
the difference between sea-bottom and mountain summit is
marked only by variations in the thickness of a line.

The diagram illustrates the insignificance of the deforma-
tions required; and that crustal disturbance occurs much
deeper than the layer with which the tetrahedral theory is con-
cerned is shown by the fact that the estimated centre of origin
of the Lisbon earthquake lies far below.

* Based on Lingg’s ‘Erdpofil.’

The Plan of the Earth and its Causes.—Gregory. 145

Sphere without Polar flattening

Stromboli Vesuvius Mt. Blanc
Oa 7

Aleaiterranean flocr ———____
Depth of Atlantic

‘Lisbon earthquake

1
Depth of 7o0 th. earth's radius

FIG. 7.—DIAGRAM OF RELATIVE EXTENT OF
INEQUALITIES ON THE EARTH’S SUR-
FACE. @, A TRUE SCALE CURVE OF PART
OF EARTH'S SURFACE; 0, SECTOR OF
CIRCLE, SHOWING RELATIVE SIZE OF
ZONE INCLUDED WITHIN @ TO THAT OF

THE EARTH.

This diagram also serves to show that the amount of con-
traction in the earth necessary to allow tetrahedral deforma-
tion is very small. This is important because, as Lord Kelvin
has shown, the amount of contraction allowable during the
later stages of the earth’s history is very limited. But geol-
ogists have the authority of Prof. Darwin for accepting a cer-
tain amount of contraction. “A cooling celestial orb must
contract by a perceptible fraction of its radius after it has con-
solidated,” he tells us, and his considerations “only negative the
hypothesis of any large contraction of the earth since the
moon has existed.”* And, unlike the contraction theory of
the origin of mountain chains, the theory of the tetrahedral
deformation of the lithosphere requires only a small amount
of radial contraction.

Finally, it may be urged that even such deformation as
the tetrahedral theory requires is impossible, since physicists
have taught us that the earth is rigid. To this objection it is
only necessary to reply that Lord Kelvin’s rigidity. argu-

* Phil. Trans., vol. 170, pp: 522, 523.

146 The American Geologist. March, 10901.

ments apply to the earth as a whole, and not to its crust; they
deny the fluidity of the interior of the Earth, and do not pro-
deny the fluidity of the interior of the earth, and do not pro-
hibit any local deformations of the exterior crust. The once
prevalent astronomical belief in the absolute invariability of
the earth’s shape and in the absolute fixity of is axis of rota-
tion (expressed, e.g., by Sir J. Herschel in 1862) no longer
hinders progress. In fact, astronomers tell us that, instead
of the absolute fixity of the pole, it now shifts its position to
an appreciable extent under the influence of the movements of
the atmosphere, the unequal melting of the polar ice, and by
heavy falls of snow on the Siberian highlands. These move-
ments of the pole are important, because they are taken to
prove a certain elasticity in the earth. The movements dem-
onstrated by actual observations are so far minute; but they
at least allow geologists to say that, as such slight causes as
those mentioned produce appreciable effects, more powerful
causes acting for longer periods would work greater changes.

SUMMaRrY.

The object of the paper is to show that the old belief in a
definite plan of the earth is justified, since the distribution of
land and water on the globe has been determined by the tetra-
hedral arrangement of the elevations and depressions in the
surface of the lithosphere.

This tetrahedral plan is shown by the existence of (1) a
northern land-belt, surrounding a northern ocean, and giving
off three meridional land lines, which taper southward; (2) the
southern ocean belt surrounding a south polar continent, and
the three meridional oceans; (3) by the antipodal position of
land and water; (4) by the course of the main watersheds and
mountain chains.

It is held that this arrangement was not established in the
earth’s infancy, and therefore has to be attributed to some
agency which has acted throughout geological history.

There are reasons for believing that a contracting sphere
with a hard crust would undergo tetrahedral deformation, and
the evidence of geodesy shows that the earth has been de-
formed from its spheroidal form. Its present figure may be
defined as a geoid, which has been derived from a spheroid
by irregular tetrahedroid deformation.

PLATE XV.

THE AMERICAN GEOLOGIST, VOL. X XVII.

.
2
k
o
Re
hl

SALEM LIMESTONE.

THE

FROM

SP.

MINUTUS, N.

ORTHOTHETES

Orthothetes Minutus, N. Sp.—Cummungs. 147

If such tetrahedral collapse be granted in the case of the
earth, then the existing arrangement of oceans and conti-
nents receives a natural explanation.

The changes in the distribution of land and seas in the past
may be explained as due to the conflict of two opposing forces,
collapse caused by the earth’s contraction producing deforma-
‘tions, which are reduced by the effects of the earth’s rotation.
Geological history affords evidence of the alternation of per-
iods of tetrahedral collapse and spheroidal recovery.

The plan of the earth may, in short, be attributed to the
continual foundering of the earth’s external shell, owing to
the unceasing shrinkage of its internal mass.

ORTHOTHETES MINUTUS, N. SP. FROM THE SA-
LEM* LIMESTONE OF HARRODSBURG, IND.
By E. R. CumMinGs, Bloomington, Ind.

Plate 2a.

The specimens described in the present paper are from the
abandoned quarry known as the Cleveland Stone Company’s
quarry located one mile north of Harrodsburg, Monroe county,
Indiana. This quarry is in the Salem limestone, and the speci-
mens come from the top layers of the quarry and also from
near the summit of the formation. They are associated with
abundant representatives of the entire Spergen hill fauna, and
are so far as I can ascertain specifically identical with the
forms from Spergen hill referred by Hall} to Streptorhynchus
(Orthis)winbraculum Schlotheim.

DESCRIPTION OF PLATE Xv.

Fig. 1. Ventral valve of a specimen 4.75 mm. broad.

Fig. 1a. Dorsal valve of a specimen 5.5 mm. broad by 4 mm. long.

Fig. 2. Profile view of a specimen 5 mm. long.

Figs. 3, 4, 5. Ventral, profile and cardinal views of a specimen 0.9
mm. broad and 0.6 mm. long.

Figs.6, 7, 8. Three views of a specimen 2 mm. broad which has an
abnormally convex ventral valve and an abnormally short area.
Only one such specimen was found and it is possible that it may
prove to belong to a distinct species.

* The name Salem is suggested by the writer ina paper now in press in place
of the name Bedford as applied to the oolitic limestone of Indiana, the latter
name having been for many years preoccupied as the name of the Bedford shale
of northeastern Ohio.

7+ Trans. Alb. Inst., vol. iv, p.12; Indiana Geol. and Nat. Hist., 12th An-
nual Rept., p. 325.

148 The American Geologist. Mant Agy

Figs. 9, 10, 11. Three views of a specimen 2 mm. broad.

Figs. 12, 13, 14. Specimen 2.5 mm. broad.

Figs.15 and 16. Ventral and dorsal interiors of two mature spec-
imens.

DESCRIPTION OF SHELL.

SHELL semi-ovate to subquadrate in old individuals ; hinge-
line usually less than the greatest width of the shell, especially
in young individuals; cardinal extremities forming an obtuse,
or sometimes a right angle with the lateral margins. Surface
firmly plicated; plications increasing toward the margins by
interstitial implantation. Crests of the plications crenulated by
numerous equally spaced fine concentric lines.

VENTRAL valve concave, with a pronounced tendency to ir-
regular growth about the beak. In mature individuals the
beak becomes strongly retrorse and greatly elevated, equalling
in hight one-half the length of the shell. Area well defined,
flat, showing in well preserved specimens a low ridge on each
side of the prominent deltidium and parallel with its margins.
The younger specimens sometimes show a perforation of the
apex of the deltidium.

Dorsav valve regularly convex, greatest elevation about
one-third of the way from the beak to the front margin, though
there is considerable variation in this respect in individuals ot
different age. Usually some flattening at the cardinal extrem-
ities. Area very narrow or scarcely at all conspicuous.

INTERIOR of ventral valve showing rather prominent teeth
which diverge widely. Cardinal process in the dorsal valve
elevated, projecting somewhat beyond the hinge-line; notch
shallow, the grooves on the posterior faces of the apophyses
very faint.

Ratio of breadth to length of an average adult individual
about as eleven to eight.

OBSERVATION. This form cannot be referred to the O.
(Terebratulites) wmnbraculum of Schlotheim*, from which it
differs in the less length of the hinge-line, fewer plications,
greater proportionate elevation of the ventral beak which in
the present species becomes strongly retrorse, and the sub-

* SCHLOTHEIM, PETREFK, I. 256, II]. 67; SCHMER, BRACHIOP. DER EIFEL,
216, t. 38, fig. 2; t. 44, fig. 4; BRONN LETH.©A, GEOG. I, 361.

oe
a +

Orthothetes Minutus, N. Sp.—Cummings. 149

quadrate rather than semi-circular outline of the shell. The fig-
ures of Schlotheim’s species also show a strongly quadrilobate
cardinal process, while in the present species the notch is very
shallow and the grooves are very faint. The species to some
extent resemble O. lens from which it differs in the form of the
cardinal process and the greater proportionate length of the
latter species.

DEVELOPMENT. In the search for specimens of this rather
rare species (about fifty specimens were found among several
thousand of the commoner Spergen hill forms) a number of
very young stages were obtained. While even the adult in-
dividuals share in the general stunting so characteristic of the
entire Spergen hill fauna no complete specimen in the writer’s
collection having a length of more than 5 mm., nevertheless
these larger individuals present the usual features of maturity.

The smallest individual observed has a length of 0.6 mm.
and a breadth of 0.9 mm. In this specimen the ventral valve is
roughly conical in shape, though slightly more convex toward
the beak which projects conspicuously beyond the hinge-line
and is very prominent. The surface shows eighteen plications
at the margin as against forty in the largest individual ob-
served, while the posterior third of the shell is without orna-
mentation except a few obscure concentric markings. The
area is high and the large deltidium less sharply marked off
from it than in the older individuals. The breadth at the hinge
is conspicuously less than farther forward.

The dorsal valve has its greatest convexity at the center and
is also smooth for a considerable distance from the beak. It
shows no sign of an area.

Individuals of the length of 2 mm. have the area perpendic-
ular to the plane of separation of the valves, and the ventral
valve showing a slight convexity toward the front. The num-
ber of plications has increased from eighteen to twenty-two or
twenty-three, and the region of greatest convexity in the dorsal
valve has approached somewhat the beak. The youngest in-
dividual shows a marked conformity to the generalized type
of brachiopod, as was found by Beecher and Clarke to be the
case in the species of the Waldron fauna.*

* Memoirs of the New York State Museum, vol. i., No. 1,

150 The American Geologist. Marty

NOTES ON PETROLEUM IN CALIFORNIA.

PROF. E. W. CLAYPOLE, D.Sc., Pasadena, Cal.

The existence of petroleum in California has been known
from very early times. The old Mission Fathers in the Span-
ish days made use of it, or rather of its solid residue after
evaporation (usually natural), under the name of “brea,” or
asphaltum, for various purposes, chiefly for roofing. Many
attempts have also been made during the past half century
to refine it but from various causes they have all failed more
or less completely until recently.

Prof. B. Silliman’s report in 1865 was the earliest scientific
statement concerning the Californian oils, and during the fol-
lowing fifteen years the attempt to establish a profitable in-
dustry were several times renewed. One of the causes of their
failure was the nature of the materials which differed from
that of the eastern oils, and presented problems not solved by
eastern experience.

The memory of men not beyond middle life will easily sup-
ply illustrations of the wild craze that swept over Pennsyl-
yania about 1865, when the desire to become suddenly rich
was met by the opportunity as the two have seldom met be-
fore. The mad excitement that almost carried the sober Key-
stone state “off its legs,” to speak figuratively, has perhaps
not been equalled since the day of the “south sea bubble” in
the lifetime of Robert Walpole. The narratives of both read
in the present day more like fiction than the literal facts of his-
tory. In reality the facts surpass fiction.

But the craze passed in California as it passed in Pennsyl-
vania and petroleum-getting has settled down into a steady
industry. Less steady, it is true, than in Pennsylvania, because
the ground is less investigated and consequently the element
of chance is a larger factor in the problem than in the East.
The conditions are less understood. Pennsylvanian exper-
ience is not necessarily or always useful in California. The
high price of fuel on the Pacific coast renders profit attain-
able in places and among circumstances which would, in the
Atlantic state, entail only loss. Consequently operators have
been compelled to a large extent to exploit the new field under

Notes on Petroleum in California.—Claypole. 151

new conditions and are now beginning to eliminate the element
of chance which so heavily hampered most of the early efforts.

GEOGRAPHY OF PETROLEUM IN CALIFORNIA.

Up to the present time the following so-called ‘‘oil-fields”
have been proved and to a certain extent developed. Most of
them are in the southern part of the state. That others will be
discovered in the future we can scarcely doubt, and that be-
fore many years have gone by the present yield of petroleum
will be largely increased, is equally certain.

The Newhall field was among the earliest to yield a profit-
able return to the investigators. As far back as 1875 a pro-
ductive bore-hole was put down a few miles to the northwest
of Newhall with the primitive appliance of a spring-pole and
auger, from which a flow of oil was obtained at the trifling
depth of thirty-five feet. This very moderate success so near
the surface stimulated further effort and next year a standard
outfit was obtained and another hole begun. This resulted in
a greater success and as Col. Drake’s first bore at Oil City set
Venango county on fire, so this well in El Pico cafion kindled
a blaze in California that has not yet died out. The well has
been flowing uninterruptedly ever since and has yielded nearly
two million barrels without at present showing any signs of
failure.

Naturally such success stimulated further experiment and
a large number of wells have been drilled in Pico and Elsmere
cafions with varying individual success, but the result on the
whole has led to the laying of a pipe line from the wells to the
wharf at Ventura forty-four miles distant. Many miles of
branch lines also run through the district.

The latest field developed in Los Angeles county is at
Whittier, a few miles southeast of the city. Since 1896 work
has been going on there continuously and successfully and it
is now one of the most productive spots in southern California.
Figures cannot be easily obtained and are not always exact,
but from more than twenty wells is obtained an average yield
of above 500 barrels, at least, daily. This is conveyed in a steel
pipe to Los Metos station a distance of three miles.

The Puente hills extend from Los Angeles southeastward
for about twenty-five miles. While scarcely equalling the rec-

152 The American Geologist. March, 1901.

ords just given, yet the fifty or more wells drilled in this field
have yielded a steady supply for more than a dozen years and
are still pumped. Their total yield is estimated at not less than
one and a half million barrels and one of the wells is reported
to have given during its first year 50,000 barrels. The oil from
this field, or rather the residuum after refining, goes by a pipe-
line to the beet-sugar factory at Chino, sixteen miles away,
which has used about 100,000 barrels a year.

Not until 1892 was any successful attempt made to develop
the various oil indications in the city of Los Angeles. In that
year a small well was drilled to the depth of a little more than
200 feet, and a yield of oil obtained which though slight, was
a stimulus to greater undertakings during the following years
until now in 1901 there are within the city limits 600 or 700
wells yielding nearly 1,200,000 barrels yearly. The total yield
from the field since it was opened is reported between 7,000,000
and 8,000,000 million barrels but the annual production has
fallen off since 1897. Wells have been bored too close together
and the sand which is neither deep nor thick, shows signs of
speedy exhaustion. The derricks stand thicker on the ground
at Los Angeles than at almost any place in Pennsylvania.

Passing to the central part of the state we find the oil-field
of Fresno county with Coalinga and Oil City as its two central
points. Numerous attempts had been made to find petroleum
before 1895 but only since that year has the region come into
the list of California oil-fields. Its yield now cannot be less
than 35,000 to 40,000 barrels monthly.

Not a few of the Coalinga wells are petroleum-geysers
which spout oil for a few minutes and then rest until the gas
again accumulates and develops pressure enough to force the
oil to a hight of some feet above the ground. This oil is
piped to the Southern Pacific railway.

South of Fresno in Kern county and near its chief town,
Bakersfield, lies another of the California oil-fields. It is sit-
uated near the southern end of the great valley of California
—the San Joaquin—and not far north of the point where the
Sierra Nevada and the Coast range come together and throw
the rampart of the Tehachapi around its southern end. In
this nook in 1897 near Bakersfield, a shallow trial well was
dug which yielded a considerable quantity of oil at the small

Notes on Petroleum in California.—Claypole. 153

depth of sixty feet. So striking a result immediately at-
tracted attention and wells rapidly multiplied in number and
increased in depth. The sand thickens to the north and west
and is so reliable that few or no dry holes have been sunk in
this field. The sand has been tested for about ten miles in
one direction and on an average for a mile and a half in the
-other.

An unusual circumstance connected with the Kern county
field is that the strata are almost undisturbed and few indi-
cations of oil are seen on the surface. The greatest depth of
the oil-sand is about 1,000 feet but the average is much less.
The quantity contained in the ground must be enormous, the
sand being more than 300 feet thick and containing, by con-
servative estimate, ten to fifteen per cent of oil.

Ventura county was the first paying oil-field of California
but until within the last twenty years the results were small.
Then began a more thorough exploration and some wells ex-
ceeding 2,500 feet in depth were sunk in Adam cafion.
There are at present more than three hundred wells in Ven-
tura county, most of them productive, but on the whole their
paying life is not long for in a year or two their yield by
pumping falls below paying level. Some have started with
300 barrels daily and are already practically dry after yield-
ing probably 100,000 to 150,000 barrels during their life-
time.

Summerland in Santa Barbara county is remarkable
among oil-fields everywhere because the work is carried on
partly under the sea. Not only are wells drilled close to the
water but many are sunk from wharves run out into the
ocean for the purpose. Of these very few disappoint reason-
able expectations. Some of these marine bores have reaclied
a depth of 800 feet penetrating two oil-sands and oil has some-
times leaked into holes dug on the beach to the depth of only
six or eight feet. No one of them gives a great yield of oil,
a few barrels a day being the average, but almost all are in
a paying condition.

The view from the beach at Summerland is unique resem-
bling no other in the world. Slender wharves of seemingly
frail construction run out from the beach and are crossed by
others like themselves so that the bay is a maze of timber work

154 The American Geologist. Marcha tent
on which stand at short intervals the derricks of the oil-men.
So close are they that it seems almost impossible for all to ob-
tain oil, yet failures are rare.

Orange county to the south of Los Angeles can scarcely be
said to have begun operations until 1896, but during the in-
terval its experiments have been attended with very promis-
ing results and already a number of companies are busy in
developing its resources. A pipe-line to the sea at San Pedro
contributes in no slight degree to the success of the operation
in this field.

Without going into too much detail for which this is not
the place, the above named districts summarize the results
of the exploration for petroleum in southern and central Cal-
ifornia. That other fields will be found is almost certain. San
Diego is making great efforts on the southern line of the state
but the results thus far are small.

The prospects in California are good and that the State
has in her oil-fields a supply of mineral fuel, to her inval-
uable, is already obvious. The high prices of coal and wood
have been a barrier, almost insuperable, in the way of her ad-
vance in manufactures, but with the removal of this she will
be in a position to take a new start in the industrial race.

Already the railways are adopting the new fuel. With the
aid of some of the many devices for burning it, which scarcely
come within our province here, it is found more economical,
clean and efficient at $1.25 or $1.50 a barrel than coal at $6.00
to $7.00 per ton. By experiment engineers have found that
two or three barrels of crude oil will do the work of a ton of
good coal without making smoke or ashes.

Other important advantages accruing from the use of oil
will at once present themselves before the mind of an en-
gineer in California, where conditions are very different from
those of the eastern states.

The present consumption of crude oil for purposes of heat-
ing and steam raising is immense, but to state it in figures is
impossible. It can, however, scarcely be put at less than a
quarter of a million barrels yearly and this would be a moder-
ate estimate.

As a general rule the California petroleum differs from that
of Pennsylvania and Ohio etc., by having as its base or more

saad

Notes on Petroleum in California.—Clay pole. 155

solid portion, not paraffine but asphaltum. In the mode of
_ “getting” it little difference exists between the two regions.
Nor do the processes of refining differ to any important de-
gree. But there are great and noteworthy differences be-
tween the products of the various fields. For example a part
of the Newhall field yields an oil almost as clear as the refined
-coal-oil of Pennsylvania and fit for use in a lamp without re-
fining. It is worth at least $4.00 a barrel at the wells. There
is no difficulty in realizing the effect which the sinking of
such a well yielding 100 barrels of the oil daily would have
upon the local market. These are the famous oil-wells of the
Placerita cafion. A heavy oil carrying a large amount of
asphaltum is found in some parts of Kern county and perhaps
not half a mile distant a lighter one more like some of the
eastern oils. Most of the Californian oils however are dark
and heavy and consequently yield a lower percentage of kero-
sene. The gravity varies from twelve or fifteen or even less
in the Kern river and Santa Barbara districts to thirty and
thirty-five at Puente and to fifty in some wells near Newhall.

OIL PRODUCTION OF CALIFORNIA.

MORO ne eee nteege a ators enka: 12,000 barrels.
ROOUEIN ERT e IS Cee ae sho ot: AGIs52iie we
Titololsh he eds al See ne TASER, cotter a mre Eo 325/000=— 1.
JO Rese ty eke meek rate SET ake A Se, 367;300°
MOEN Ee oP Oiler enh Se oA. g Oma
ROOM eet aes Sah ete tia sia Res ake oe oA 1,252,777 2
MGM its oe 7 ie whe vit aa an viata a Om tte to UA OO AAEL B
Oe Hal ee ce ea Fee ch os eee Ri ee 2,257,207 3
1899 2,665,709 %

Geology. Not the least surprising fact to the geologist
accustomed to the conditions in the East is the recency of
the oil-bearing strata and the shallowness ‘of the wells. Most
of California is a young state geologically and no one of her
petroleum yielding rocks is of earlier than Cretaceous date,
whereas in Pennsylvania and other eastern states few are later
then the Chemung of the Devonian and many of them, as in
Ohio, as early as the Trenton of the Ordovician system. In-
deed in the western and central parts of the state, strata of
earlier date than Cretaceous are comparatively rare, almost
the whole surface being composed of late Mesozoic or Ceno-

150 The American Geologist. March, 1901.

zoic formations. The following table will illustrate this de-
tail:

Stockton, Quaternary.

Puente, Los Angeles, and Kern Co. Pliocene.

Ventura, Los Angeles, Kern Co.,

Newhall. Miocene.
Ventura, Fresno, Kern Co. Eocene.
Colusa Co. and Sacramento Valley. Cretaceous.

The general horizons only of the oil-bearing strata are here
represented. Minute details are not yet attainable, nor would
it conduce to the clearness of the outline to crowd it with de-
tail.

The oil-bearing strata are usually sandstones interlam-
inated with shale as in the East, and both often show traces of
petroleum, but the accumulations are in the sandstones. Signs
of disturbance also are visible in many places sometimes ac-
companied with some degree of metamorphism.

In considering this subject we should bear in mind the
fact that the geomorphy of California indicates intense oro-
genic action at a very recent time. Strata of late Tertiary
date are contorted and compressed that they stand vertical over
large areas. The final elevation of the Sierra Nevada and
Coast range is not apparently earlier than the Pliocene; per-
haps even later. The proportion of living species among the
fossil forms abundantly proves the recency of the strata. The
energetic and extended volcanic action visible in so. many
places is evidenced by lavas so new that they have apparently
only just cooled and are scarcely yet touched by erosion.

The Aniiclinal Theory. The accuracy of the anticlinal
theory of the accumulation of oil and gas, as developed by
Prof. I. C. White, in Pennsylvania, has received abundant
confirmation from California. In many of the fields the line
of development on the surface clearly coincides with the anti-
clinal line underground, and even where the strata are very
slightly disturbed exact data will probably reveal undulations
of low angle or irregularities, such as those that govern the
accumulations in many places in the east.

Where the anticlinal ridges can be traced they are in most
cases relied upon as safe guides for extending the investiga-
tion.

Notes on Petroleum in California.—Claypole. 157

As might be inferred from a map the strike of the Cali-
fornian anticlines is usually northwest and southeast or nearly
so. Many of their ridges though of so recent formation have
been eroded and consequently their oil, or at least its more
volatile portion, has escaped leaving either no residue or only
the “brea’ or asphalt to indicate its former presence.

These facts supply a rational base for the belief that when
the strata are deeply covered, numerous yet unknown oil-fields
will be found that at present lie below the depth explored and
can only be detected by systematic geological study and juh-
cious exploration with the drill. The greater degree of erosion
in the northern counties is also the probable explanation of the
present limitation of the oil-fields to the south of the state.
At the same time we must recollect that holes more than
1,000 or 1,500 feet in depth are almost unknown.

Nature and use of the oil. Probability scarcely indicates
that Californian petroleum can compete with the Pennsylvanian
product as a source of illuminating oil. It more resembles the
Russian and the Ohio and Indiana petroleum in this respect.
But as already mentioned its great value to the State will be
its fuel value. Where the lighter grades are produced the
illuminating ingredients will doubtless be distilled off and the
residue will then be of equal or greater value as fuel. This is
already done. The heavy oils will however find their value
and use in taking the place of coal and supplying heat in many
cases where the cost of coal would be an insuperable barrier.
The lower price of oil, its transportation by pipes, its supply
to the furnace by gravity, the absence or slightness of the
smoke and ash, the avoidance of stoking, all these are advan-
tages which cannot be over estimated in a comparison of the
two fuels. To say that the exploitation of petroleum has
given California an open door where before it seemed hope-
lessly closed, is not an exaggeration of the fact or too roseate
a picture of the prospect.

The Future. It is too soon of course to prophesy the
future by predicting the duration of the supply. But in spite
of all anticipation of a speedy failure, the eastern yield has
not yet run out. It has continued beyond most calculations or
prognostications made forty years ago and there is even now
reasonable ground for expecting early exhaustion. Nor is

158 The American Geologist. Mater

there any reason for hoping less in California. That the sup-
ply is finite is of course undeniable, but though finite it is so
vast that the present generation and perhaps one or two more
that will come after it may be enriched by this wonderful fund
of latent power stored in the distant Tertiary era from the
remains of Tertiary life.

The California conditions, moreover, render many wells
which in the East would’ be useless, because unprofitable,
sources of profit to their owners. Wells yielding one barrel
of oil daily would scarcely be valued in Pennsylvania but here
they are, to say the least, quite above the line of “no profit.”
The initial cost is small often not above $200 or $300, and the
pumping can be done at a price not exceeding fifty cents
daily, while the price is seldom below and often above one dol-
lar at the well. If the bore is deeper and the cost therefore
higher the oil obtained will probably be lighter and consequent-
ly of greater value in the market.

The duration of the individual wells also is not very
different from that expected in Pennsylvania. Some have been

pumped for twenty years and still are yielding a paying

amount of oil. There is, therefore, no more ground for dis-
trusting the duration of the Californian wells than there was
thirty years ago for distrusting those of Pennsylvania.
Besides the kerosene produced from the crude petroleum
a large quantity of lubricating oil is obtained occasionally in
a pure form, otherwise by distillation. Then there is the
asphaltum base of the oil, either left after the lighter portions
have been distilled off or found in beds in the earth—the pro-
duce of natural distillation. At first an annoyance as a by-
product and a waste, tending to cause smoke on burning the
kerosene, it is now one of the valuable products of the re-
finery. Masses of it are even thrown up on the beach in some
places—the product of petroleum escaping from the sea-bot-
tom. Elsewhere, as at Obispe, near Terminal island, huge
masses of this mineral are quarried in the cliff, as rock, re-
fined and sent abroad and to the eastern states chiefly for pay-
ing purposes. It occurs in disjointed and contorted strata
or seams, often many feet thick and in quantity can be com-
pared only with the great pitch deposits on the south Amer-
ican continent or the lake of Trinidad. It is sent largely to

Notes on Petroleum in California.—Claypole. 159

the eastern states where it is sold at a good profit. Being a
solid it canot be passed through pipes but a very ingenious
device has been recently adopted to transmit it. The as-
phaltum is dissolved in naptha and in this condition of solu-
_ tion passed through the pipe-line from the mines of Santa

Barbara county to the coast where the naptha is evaporated
and sent back for another load of asphaltum.

Little has been said here about the gas that accompanies
the petroleum, though its quantity and value are large, be-
cause it has not yet come extensively into use as an illuminant.
Unfortunately the wells where the gas pressure is greatest
are usually far removed from cities and sufficient confidence
is not yet felt in its persistence to warrant the laying of pipes
to carry this most valuable and convenient fuel from the place
of production to the place of consumption. Should its flow
continue and increase there is no doubt that the day of its
utilization will soon arrive. As yet, however, no Murrays-
ville or Grapeville or New Washington has been evolved in
California.

Since the above paper was written news has come from
Texas of a discovery of petroleum which may fairly be com-
pared with some of the greatest on record. At Beaumont,
near the mouth of the Nachet, a tributary of the Sabine river,
a bore-hole was drilled with the intention of experimenting
but apparently without any very strong confidence in the re-
sult.

Allowing for considerable exaggeration in the early re-
ports, we cannot doubt that a new and important factor has
come into the problem and one which may have great conse-
quences. It must equal most of the great gushers even if it fall
far short of the 25,000 barrels a day first reported. From a six-
inch hole the oil is said to jet to the hight of 200 feet.

For four days the flow continued and to check it was im-
possible. Before this was at last accomplished it was esti-
mated that 150,000 barrels had flowed out much of which had
been saved in hastily constructed earthen tanks. The well has
been since reported to yield 8,000 barrels daily. It‘is only
twenty miles from the coast.

Later still comes a similar report from the older oil-field
of Indiana which, though on a rather smaller scale indicates
that the days of “oil-strikes” have not yet altogether gone by

160 The American Geologist. Mere

SOME SALIENT FEATURES IN THE GEOLOGY OF
ARIZONA WITH EVIDENCES OF SHALLOW
SEAS IN PALEOZOIC TIME.

By WILLIAM P. BLAKE, Tucson, Arizona,

The geology of the northern portion of the territory of Ari-
zona including the grand cafion and the plateau region has been
studied and mapped by Powell, Dutton and others of the U. S.
Geological Survey. Blandy has published some papers relat-
ing to central Arizona; the writer has contributed some special
papers and desultory notes in reports to the governors of the
territory and elsewhere, but in regard to the country south of
the great plateau region very little systematized information
has yet appeared in print.* An explanation may be found in
the fact that the region is vast and difficult of access and until
recently has largely been under the domination of the savage
Apache.

Capt. Dutton in his monograph upon the Tertiary history of
the grand cafion district, frequently refers to an unknown “Ari-
zona Land.” In this he shows a mental reaching out for far
off shores from which a portion, at least, of the mighty mass of
sandy sediment in the basin of the Colorado could have been
derived.

Investigations in southern Arizona sustain the idea of the
former existence of such shores, not perhaps as continental
margins but as island ridges; crests of submerged mountain
ranges rising at intervals above the waves of shallow seas,
and with a trend or direction corresponding essentially to the
trend of the mountain ranges of the region.

A cross-section of the territory in a northeast direction from
the head of the gulf of California, the sea of Cortez, to the line
of New Mexico, a distance of nearly 350 miles shows a suc-
cession of mountain ranges separated by long trough-like val-
leys often broad plains or mesas. There are some fifteen such
main lines or axes of elevation with a general northwest and
southeast trend. Commencing first at the gulf we have in suc-

* Since this paper was written a memoir has been published by Dr. THEO.
B. COMSTOCK, in the Transactions of the Am. Inst. Mining Engineers, entitled
‘“*The Geology and Vein Phenomena of Arizona.’’

A partial bibliography of contributions to the Geology of Arizona may be
found in Bulletin No. 127 of the U. S. Geol. Sur. and also in the Report of the
Governor of Arizona for 1899,

:
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:
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{
:

Geology of Arizona.—Blake. 161

cession the Gila range; Mohawk and Castle Dome; Growler
Ajo; Maricopa, and Quijotoa, Baboquirari; Tucson, Santa
Catalina, and Rincons, (extending northward to the
Bradshaw group of elevations), the Santa Ritas (east of the
valley of the Santa Cruz), the Huachucas and Whetstones ;
the Dragoons and Mule mountains (Tombstone), extending
north into the Galiuro; the Pinaleno and Chiricahua, the Pilon-
cillos east of the San Simon plains; ending with the Natanes
and Prieto plateau and the Four Peak mountains.

These several mountain ranges may be considered as suc-
cessive axes of uplift, or structure, with well-defined occur-
ences of Paleozoic strata, generally resting upon a foundation
of granite and Archean gneiss. Regular anticlines and syn-
clines are rare. Monoclines are the rule, as for example in the
Huachucas and Santa Ritas.

The presence in all these ranges of massive strata of quartz-
yte, and frequently of coarse conglomerates referable in age to
the Paleozoic, or earlier, bears conclusive testimony to the ex-
istence of shore-lines and of shallow seas in that early period of
continent making. But there are also deep sea lime-stone of De-
vonian and Lower Carboniferous age and other limestones
probably Silurian.

Coal Measures. In the Chiricahua mountains we also find
evidences of Coal Measures and vegetation of that period in
the shales and uplifted beds of graphitic anthracite several
feet thick. So, also, in the San Carlos region, and northwards,
heavy strata of the Carboniferous occur with seams of coal, but
so far as yet determined of limited thickness and value. These
occurrences are, however, sufficient to show a far western ex-
tension of the vegetation of the Carboniferous and consequently
the existence of dry or swamp land at that time. The most
western point in the latitude of Arizona at which Coal Meas-
ures have before been found was in the Rocky mountains near
Santa Fe.* Thickly bedded limestones of dark color and of
Carboniferous age occur in the mountains west of Tucson.
The limestones in the Quijotoa mountains at the Vekol lead-

*In 1857 I collected fossil ferns near Santa Fe which the late Mr.
LESQUEREUx identified as specifically the same as several species found in the
Pennsylvania coal measures. PROF. DANA, in his fourth and last edition
Maunal of Geology, p. 658, says ‘‘A Carboniferous formation without coal is
the great fact for the western half of the eontinent,’’ a statement which in the
light of the above facts needs some modification.

162 The American Geologist. March, 1901.

silver mines contain an abundance of cyathophylloid corals
and are referred to the Carboniferous. The dark colored
limestones of the Mule mountains, at Tombstone,* and also
those at the American mine in the Swisshelms are similarly
referred, and are doubtless a part of the extensive series of
limestone and shaly beds of the northern portion of the Santa
Ritas; and a portion of the strata of the Whetstone range
and of the Dragoons, and of the Galiuro mountains are of the
Carboniferous age.

Cambrian. Most of the outcrops of massive quartzyte
uplifted and in contact with granite at several distant places
are referred with some hesitation to the Cambrian. Such
outcrops are found from western Sonora in nearly all the
chief uplifts as far east as the Chiricahuas. In northern
Sonora near the boundary line in nearly the southeastern con-
tinuation of the Gila and Mohawk uplifts, a well defined
ancient quartzyte stands in vertical beds alongside of an
intrusive granite. This quartzyte is marked by perforations
like those of the Potsdam and probably properly referable
to Scolithus. Conglomerates and quartzytes occur in the
Buboquirasi range and in the Tucson mountains where there
is a great thickness of strata in regular folds, probably rep-
resenting a large part of the Paleozoic. Massive conglom-
erates with thoroughly rounded pebbles firmly cemented to-
gether occur near the source of the Canada de Oro in the
northern part of the Santa Catalina mountains; also at the
American Flag rancho in the same mountain range. We
again find coarse conglomerate opposite the mouth of the
Arirapa near the site of old Fort:Grant where quartzytes
also occur resting on granite. Thickly bedded conglomerates
occur over wide areas south of Tucson in the region of
Ariraca and again in the northern portion of the Chiricahuas.
It is not at present possible to correlate all these occurrences
which no doubt represent different horizons, but they are all
believed to be Paleozoic, or older. They bear united testi-
mony to the former existence of shore-lines and rapid cur-
rents.

Beginning of Arizona Land. The Santa Catalina, Rin-

_*See my paper on the Geology and Veins of Tombstone, Trans. Am. Inst.
Min. Engrs., X, 334.

aritn

Geology of Arizona.—Blake. 163

con, and Rillito group may be regarded as the northwestern
extension of the great mass of mountains in central Arizona
generally known as the Bradshaws. All these mountain
ranges consist largely of granitic, gneissic, and schistose rocks
of pre-Cambrian age with a highly complex folded structure,
and exhibiting a high degree of meta-morphism. Taken to-
gether, these mountains may be regarded as the main axis of
ancient uplift, and of insular land areas in the pre-Cambrian
and Palzozoic periods, the beginning of the “Arizona Land.”
' Gneiss. The gneiss of the southern side of the Santa Cata-

lina near Tucson is regarded as Archean. It is remarkable
for its regularity of stratification and its great thickness, prob-
ably over 10,000 feet. It occurs in great tabular masses made
_up of thin layers which when seen laterally give the appearance
of evenly stratified shales and sandstones. The beds are, how-
ever, essentially granitic with the feldspar spread in nodules
which make protuberances on the cleavage surfaces of the rock,
and thus form a porphyritic or augen-gneiss rock.

Sheets or veins of granite are common in this gneiss. It
is remarkable that this rock has such an even tabular
structure without plication, wrinkling or folding and that it
rests at a low angle generally not exceeding twenty degrees
upon the massive nucleus of the Catalinas dipping southward
and passing under the modern detrital accumulations, or
“wash”, from the mountains. These beds rise nearly to the
summit of the Catalinas and then break off precipitously form-
ing a line of cliffs facing the central part of the range. Some
obscure traces of an anticlinal fold are visible on the western
side. ote

Huroman or Arizonan. In the same range, but on the
northeastern side, facing the valley of the San Pedro, another
formation of thinly bedded and highly crumpled mica schist in
sharply defined zig-zag folds is referred to the Huronian. This
is the formation to which I have given the name Arizonan. Stil!
further north occur the heavy conglomerates, red beds, quartz-
ytes and limestones in which last corals referable to the Devon-
ian occur. A section carefully measured in detail made here
may be generalized as earthy limestone in thin layers with sand-
stone and quartzyte at the base. The strata dip eastwardly at
a low angle. Their exact stratigraphic relation to the under-

‘

104 The American Geologist. March, 100%,

lying red shales and sandstones has not been satisfactorily de-
termined.

Devoman. Near Greaterville in Prince county on the east-
ern side of the Santa Rita mountains I have found a locality
of Devonian fossils in limestone, and have collected Spirifer
hungerfordi, Atrypa recticularis Bellerophon and the coral
Acervularia davidsom, besides others not yet determined.*
These occur in a massive bed of light colored limestone stand-
ing nearly on edge contiguous to a thick stratum of limestone
conglomerate made up of rounded pebbles of limestone, un-
questionably derived from some older beds.

In the Box cafion which cuts through this mountain from
east to west there is a remarkably interesting section. Resting
upon a coarse porphyritic granite at the western side we find in
nearly vertical attitude a pebbly conglomerate overlaid by
quartzyte and this in turn by a thick series of red shales prob-
ably over 1,000 feet thick. At the eastern end a last exposure
ot this section, the fossiliferous limestone, the equivalent of
that at Greaterville and like it, accompanied by the calcareous
conglomerate, crops out in such a way as to render its relation
to the red shales obscure. There is seemingly a break and want
of conformity as at the Catalina section farther north.

Faulting. There have been great faultings and displace-
ments over the entire area of Arizona, notably along the valley
of the San Pedro northwest and northeast.t In the Huachuca
mountains on the western side of this valley the dominant char-
acteristic section is a very heavy regularly stratified quartzyte
surmounted by limestone and resting upon porphyritic granite
and presenting bold escarpments towards the east. In the sec-
tion of these mountains thick beds of red shales are found like
those of the Santa Ritas, while higher in the range there are
massive strata of limestone conglomerate apparently not con-
formable with the red shales. This conglomerate appears to be
the equivalent of that found in close association with the De-
vonian limestone of Greaterville.

Silurian and Cambrian. We are without evidence by fossils
of the existence of Silurian terranes, but the identification of a

* In the identification of the species mentioned I have had the assistance of
Prof. C. E. Beecher of the Peabody Museum, Yale University.

+ Such faultings have been noted and described by Dr. COMSTOCK.

Geology of Arizona.—Blake. 165

Devonian horizon permits us to believe that we have represen-
tatives of the Silurian and Cambrian in the underlying strata.
The relation of the Devonian limestones to the sub-jacent beds
is under investigation. It is believed that representatives of
the Silurian and Cambrian systems will be found and that in
the basal quartzytes and conglomerates we have Cambrian beds.

_ Extensive outcrops of fine-grained mica and clay slates are
found in the Dragoon uplift north of Russellville, and beyond
northward.

A region in the eastern part of the territory covered by the
White mountain Indian reservation is as yet but little known.

Crystalline Rocks. The underlying foundation rock in
southern Arizona is a coarse-grained porphyritic granite which
much resembles the typical granite of Belihen in the Vosges.”
This granite is found in the Santa Ritas, in the Huachucas at
Guma, and at and beyond Oracle at the north end of the Santa
Catalina uplift. Here it extends northward to Mammoth and
beyond towards Riverside, the Superstition mountains and Salt
river east of Florence. It underlies the tufas and lavas at Gila
buttes at the head of the Florence canal. It presents generally
a broad apparently eroded surface and here and there includes
belts and portions of fragmentary rocks, quartzytes, and lime-
stones, as for example in the Gold Field region east of Mesa
and on the road from Tucson to Oracle. Large areas of gran-
ite exist in the Bradshaw mountains, notably at and around
Prescott. These are granite which weather into fine large
bowlders of decomposition at Peeple’s Valley, Yarapai county ;
at points north of Phcenix, at Tombstone and other localities
notably north of Dragoon Summit near the Wolfram veins.
Plutonic intrusions in the form of dykes abound both in the
crystalline and fragmentary formations. Distinct local met-
amorphism is common where dikes of porphyry cut through
limestone with the production of bordering masses of garnet
rock often penetrated by copper sulphide. :

A large extinct volcano, Pinacate, rises just below the south-
ern border near the head of the gulf of California, but it is not
comparable in magnitude and grandeur with San Francisco
mountain near Flagstaff and the neighboring cones dominating
the plateau south of the grand cafion. Lava streams of compar-

* Vide the series of typical rocks from Krantz of Boun.,

166 The American Geologist. March, 1901,

atively modern date geologically are more abundant in the
southwestern portion of Arizona than in the central and eastern
portions, but there are considerable areas of rhyolyte in the
Chiricahuas and of volcanic tuffs and lavas at Tucson, and in
the valley of the Hassayampa south of Prescott.

Mesozoic. Formations of the Mesozoic are not absent in
southern Arizona. The massive red sandstones north of
Phoenix, of Tempe and Mesa in the Salt river valley are re-
ferred to the Trias. So also the extensively developed red beds
of the southern side of the Bradshaws at Castle creek. East
of Tucson near Vails and Pentano, stratified sandstones and
shales are probably Mesozoic. A wide area of disturbed red sand
stones and shales between Oracle and the Gila at old Camp
Grant and apparently unconformable to the uplifted conglom-
erate, quartzyte and limestone are probably Mesozoic.

There are evidences of the presence of Mesozoic sandstones
in the Sulphur Spring valley. The Trias is largely represented
south of the international boundary line in Sonora. But the
identification in all these localities rests upon stratigraphical
and lithological characters rather than upon fossils. _ .

The recent discoveries of remains of Elephas and of the
Mastodon at several distant points, and of the horn cores of
a giant form of Bos all indicate former conditions of greater
precipitation and of more abundant vegetation than now exist.

Pleistocene Lakes. We also have evidences of extensive
interior lakes in the later Tertiary or in the Pleistocene period.
The valley of the San Pedro exhibits a great thickness of hori-
zontal lacustrine clays, generally of red color, extending from
the Mexican border northward to and beyond Penson on the
Southern Pacific R. R., where they are cut through by the river
to a depth of 600 feet or more. The northern barrier of this
lake was probably in the narrow valley between Benson and
Dudleyville. By the cutting away of this barrier the lake has
been drained. For this ancient lake I have proposed the name
Quiberi, the ancient Indian name of the San Pedro valley and
river.

The great Sulphur Spring valley between the Dragoon
mountains on the west and the Chiricahua mountains on the
east is also regarded as the dried up bed of an ancient lake of
great extent.

The Lake Systems of Southern Patagonia.—Hatcher. 167°

Detrital Deposits. The detrital deposits of the Pleistocene,
or Quaternary, are developed on an enormous scale in southern
Arizona. They everywhere skirt the mountains in the form of
extended slopes often twenty miles or more in length which
arrest the eye by their wonderful regularity of outline truly
represented in a photograph or picture by a straight line in-
clined two or three degrees to the horizon.

THE LAKE SYSTEMS OF SOUTHERN PATAGONIA.

By J. B. HATCHER, Carnegie Museum, Pittsburgh, Pa.
PLaTe XVI.

Until recently, the interior of Patagonia has remained prac-
tically an unknown country. A few of the earlier travelers had,
it is true, penetrated into the interior, but for the most part they
followed one of two routes. Some chose the Santa Cruz river,
which, discharging into the Atlantic at about the fiftieth paral-
lel of south latitude, forms an unbroken waterway, for vessels
of light draft, from the sea to lake Argentino at the base of the
Andes, 150 miles to the westward. Others, starting from the
same point, selected a more northerly route, and after leaving
the mouth of the Santa Cruz river, followed the old Indian trail
that, for centuries, has formed the highway of communication
between the southern Tehuelches and the Araucanians and
other Indian tribes inhabiting the country watered by the
Chubut, Negro, and Colorado rivers, far to the northward.

This trail, after leaving the Santa Cruz river near its mouth,
assumes a northwesterly direction, and taking advantage of the
valley of the Rio Chico which has cut a practical highway
through the broad lava beds that cover most of the central
plains of southern Patagonia, it ascends this stream to a point
some forty miles distant from the eastern base of the Andes.
At this place a tributary valley enters the main river valley
from the north. This valley connects with other similar lateral
valleys tributary to the drainage systems lying to the northward
and thus there is formed a continuous highway extending par-
allel with the base of the Andes from the Rio Chico to the Rio
Negro.

N (hes the Bulletin of the Geographical Society of Philadelphia, vol. ii,
NO. 6.

168 The American Geologist. March) {082

The northern of these two routes was the one traversed by
Lieut. Musters more than thirty years ago; while the southern
was chosen by Darwin, Moreno, and others. Few travelers
diverged far from either of these natural highways, so that
much of the interior of Patagonia remained a terra incognita
until quite recently. Within the last five years, however, our
knowledge of the interior of this country has been very greatly
increased. This has been accomplished chiefly by the explora-
tions of the Argentine and Chilian boundary commissions, sup-
plemented, perhaps, by the expeditions conducted by the pres-
ent writer in southern Patagonia in behalf of Princeton Uni-
versity. To these explorations must be accredited the discov-
ery of many new lakes, rivers, mountains, and other geographic
features, as will at once become apparent by a comparison of
the sketch map accompanying this paper with any of the older
maps of the same region. This is especially true of that region
lying between the Rio Santa Cruz and the forty-sixth parallei
of south latitude.

It is not the purpose of the present paper to chronicle any
of these discoveries, but rather to discuss the origin of some of
the geographic features, and more especially of the lakes which,
as will be seen by a glance at the accompanying map, consti-
tute an important part of the physiography of this region.

The lakes of southern Patagonia may be divided according
to their origin into three classes, viz.: residual, glacial, and
tectonic. Of by far the greater importance are the lakes of
tectonic origin. By referring to the map, an intricate series
of lakes will be seen to extend in a line approximating that of
the seventy-second meridian of west longitude throughout the
entire length of the region under discussion. The exceedingly
irregular outline of nearly all these bodies of water distin-
guishes them at once as true mountain lakes. Though the east-
ern extremities of many of them occupy lateral valleys thai
have been cut through the eastern range of the Andes and pro-
ject well out into the great plain that extends from the moun-
tains to the Atlantic, yet they one and all penetrate far to the
westward, extending quite through the eastern foot-hills and
sending out numerous arms and ramifications into that laby-
rinth of deep mountain gorges that separate the eastern lateral
range of the southern Andes from the central and main range
of the same mountain system.

ar
THE AMERICAN GEOLOGIST, VOL. XXVII. PLATE XVI,

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THE AMERICAN GEOLOGIST, VOL, XXVII.

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: 3 Ki, se i [prs cruz
\, ee ce MAP OF
ye | ' SOUTHERN PATAGONIA

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aD iV BA\\ SOUTHERN ARGENTINA
; i A BY DR. FRANCISCO P. MORENO,
with additions and corrections by
eae J. B. HATCHER
Scale of Miles
2 2 2 2

Hi. Loganaiet

The Lake Systems of Southern Patagonia,—Hatcher. 169

Many of these lakes, like Argentino, Viedma, San Martin,
Pueyrredon, and Buenos Aires, are of large size, fifty to 109
miles in length, or even longer. None of them have as yet been
fully explored and accurately charted. All of them are, except
on their eastern shores, surrounded by lofty, precipitous moun-
tains. The summits of the latter are covered with immense
fields of snow and ice, from which descend glaciers that occa-
sionally extend quite down the mountain slopes into the waters
of the lakes. Huge blocks of ice are frequently detached from
the front of such glaciers and float off into the lake as icebergs
of no inconsiderable proportions.

The basins occupied by these lakes are largely of tectonic
origin and they are chiefly due to the unequal folding of the
strata that took place during the elevation of the southern
Andes in late Tertiary times.*

With the exception of lakes Viedma and Argentino, this
great series of lakes all discharge their waters into the Pacific,
notwithstanding the fact that they lie entirely to the eastward
of the main range of the Andes, and that the eastern extrem-
ities of most of them project even into the great plain of east-
ern Patagonia.

Just to the eastward of this series of lakes of tectonic origin
and situated on the plains, entirely without the foot-hills of the
Andes, there is a second series of lakes evidently of glacial or-
igin. For the most part these lakes are of small size and of
minor importance, though some of them, like Lagoona Blanca,
lake Cardiel and lakes Colhue and Musters (the two latter
are not shown on the accompanying map, since they lie some-
what beyond the forty-sixth parallel) are of considerable di-
mensions. These lakes have for the most part originated from
the damming of preglacial drainage systems with glacial de-
tritus during the recession of the glaciers that occupied these
valleys at the close of the glacial period. Like the lakes just
mentioned they contain fresh water. Although for the most
part they have no surface outlet, the circulation permitted by
the confining glacial drift is usually sufficient to keep the

* For a further discussion of the origin of these lakes, see ‘‘Some Geographic
Features of Southern Patagonia, with a Discussion of their Origin,’ by J. B.
HATCHER: Nat. Geogr. Mag., vol. xi, pp. 41-55.

170 The American Geologist. March, 1901.

waters sweet, but a few of them do in very dry seasons become
somewhat brackish.

Scattered all over the Patagonian plains from the strait of
Magellan to Bahia Blanca are great numbers of salt lakes. Such
lakes are usually of quite limited area and of exceedingly shal-
low depth, though they occasionally attain to considerable di-
mensions. In reference to their origin I have called these salt
lakes residual lakes. I have elsewhere advanced the theory
that these lakes have resulted from confined bodies of water,
cut off from the sea, during the process of elevation, which be-
gan at the close of the Tertiary and which resulted in the final
recovery of this region from’the ocean. I have held that the
salt of these lakes has been derived directly from sea water and
has not resulted by evaporation from the surface of an orig-
inally fresh water lake with no outlet. No doubt some of the
salt and other saline matter found in these lakes has been de-
rived in this manner, but I believe that for the most part it has
resulted directly from the evaporation of confined bodies of
sea water. From the paleontologic and geologic evidences it
is apparent that for a considerable period in late Tertiary times
this region was elevated above the sea and subjected to erosion.
During this period of late Tertiary elevation all the more im-
portant of the present drainage systems were outlined. Near
the close of the Tertiary there was a subsidence just sufficient
to permit the ingress of the sea. This submerged condition
prevailed only for a relatively very short period, but sufficient
for the deposition over the previously eroded surface of a thin
layer of sedimentary rocks with characteristically marine fos-
sils. At the close of the Tertiary a period of very gradual ele-
vation set in, resulting in the final ‘rescue of what is now south-
ern Patagonia from the sea. As this land-mass gradually
emerged, the higher table lands separating the previously
eroded water courses would be the first to appear as islands
and peninsulas separated by narrow channels and bays formed
by the valleys of the drainage systems mentioned above. As
the elevation continued the bottoms of such valleys would be
successively brought above the water level and numerous small
bays would be formed in all the smaller tributaries. Across
the mouths of such bays bars would be thrown by the action of
the tides. The formation of such bars, together with the grad-

The Lake Systems of Southern Patagonia.—Hatcher. 171

ual elevation constantly taking place, would tend to decrease
the circulation between the waters of the bay and the ocean.
By the combined action of these two agencies, the circulation
would be more and more impeded until a stage would be
reached in which this circulation would become intermittent.
The two bodies of water would then be entirely separated,
except during periods of unusually high tides, when the waters
of the sea would rise sufficiently to overflow into the bay, or
lake as it might now be more properly termed. At first the ob-
struction would not be so great but that the bi-weekly high
tides occurring with each full and new moon would produce ~
a flow of water from the sea into the lake, thereby replenishing
every two weeks the water lost by surface evaporation with a
new supply of sea-water. After a time the obstruction would
become so great that only the exceptionally high semi-annual
tides would suffice for its submergence, and the replenishing
of the waters of the lake would then occur only once every six
months. After this a stage would be reached when ordinary
spring tides would no longer suffice, and only an exceptionally
high tide brought on by a continued strong easterly wind, act-
ing in conjunction with the sun and moon at the period of
spring tide, would pile up the waters of the sea sufficiently high
to overflow the isthmus separating it from the lake. Such con-
ditions would, of course, occur only at irregular intervals and
would constantly become less and less frequent, until finally all
communication would cease and the smaller body of water
would become entirely separated as an inland salt lake, grad-
ually diminishing in area after the last overflow, by evapora-
tion from its surface until a point would be reached when the
loss by evaporation would just balance the gain from tributary
streams and springs, which latter, in the lakes in the region
now being considered is exceedingly slight.

It was during these stages of intermittent communication
that the salt deposits were formed. These deposits are now
found often covering the bottoms and adjacent shores of the
lakes to a depth of several feet. During periods when com-
munication between the lakes and the sea was suspended, the
volume of water in the former would be greatly reduced by
evaporation, thus increasing its salinity until an oversaturated
solution would be attained, resulting in the precipitation of

172 The American Geologist. Mert

considerable quantities of salt. With the next ingress of the
sea a fresh supply of salt would be introduced in solution, to
be deposited in the same manner during the next period of
suspended inter-communication. Such conditions, continued
over a long period, have resulted in the deposition of the con-
siderable bodies of salt now found in and about these lakes.

In the manner just described series of salt lakes were
formed and may still be seen occupying slight depressions over
the bottoms of all the abandoned water courses of Patagonia ;
while every stage in the process of the formation of such lakes
may be observed in and about the heads of the different inlets
all along the coast. Exceptional advantages for studying the
origin of these salt lakes are offered at the head of the bay of
San Julian and in the valley extending from the bay into the
interior for a distance of 100 miles. In the bottom of this val-
ley are numerous salt lakes, while in the region about the head
of the bay there is a succession of lakes and inlets, showing
every stage in the process of lake formation as detailed in the
foregoing lines.

Dr. Otto N6rdenskjold has taken exception to this theory
of the origin of these salt lakes, holding that they are not res:-
dual lakes, and that the salt has not been derived directly from
the sea as I have maintained. He holds that the salinity ot
these lakes is due to the fact that they have no outlets and that
the salt has been derived, as in many other salt lakes in other
countries, from the surrounding rocks by the tributary waters.
To my mind there are two very conclusive arguments against
this theory and in favor of that of considering these as residual
lakes. First:—None of these lakes are fed by perennial
streams, their supply of water being almost entirely limited to
freshets due to occasional heavy showers, and to melting snow
in the immediate vicinity, so that it is entirely made up of sur-
face water and necessarily contains very little, if any, saline
material. Second:—Those lakes found nearest the coast and
whose connection with the sea has only just recently been
completely closed, are found to contain quite as important salt
deposits as others situated many miles inland where the connec-
tion with the sea has long been severed ; thus showing that the
amount of salt in the latter has not been appreciably increased
during the long period that has elapsed since their final sever-

The Lake Systems of Southern Patagonia.—Hatcher. 173

ance. These facts, together with the observations made illus-
trating the method of formation of these lakes about the heads
of many of the inlets of Patagonia, lead me unhesitatingly to
pronounce them residual in origin, and as having derived the
beds of salt found in and about them almost entirely from the
sea direct.

Of the three systems of lakes described above, the first, or
those of tectonic origin, are in point of size of vastly more im-
portance than either of the other two. When Patagonia is
finally opened up to civilization and its many natural resources

‘are fully recognized and taken advantage of, this superb series
of magnificent mountain lakes will come to be more generall:
realized and appreciated. They will then, no doubt, achieve an
importance and consideration commensurate with their excep-
tional size and beauty. Hitherto, owing to their inaccessibil-
ity, few indeed are those who have been enabled to see them;
but, buried deep in the recesses of one of the most lofty and
rugged mountain systems to be found anywhere on the sur-
face of our earth, by those favored few they will ever be re-
membered as masterpieces of creative ingenuity. Extending
from the barren lava beds and bleak, cheerless plains of the
east through the forest-clad slopes of the foot-hills on into the
remote and silent recesses of the central range of the Andes,
whose summits, rising ever higher, are finally lost in immense
fields of snow and ice, they present along their shores a greater
variety of physiographic and geologic features than may be
observed elsewhere in an equally limited area.

Of the three systems of lakes described above those of
glacial origin are, perhaps, economically of the least import-
ance of all. Yet, lying among the drumlins and terminai
moraines of the ancient glaciers, where are now to be found
the best pasture lands of the Patagonian plains region, they
will become of ever increasing importance as these lands are
more and more occupied for pastoral purposes.

The salt from the residual lakes will always supply the lo-
cal demand for that useful article and permit also of the annual
exportation of considerable quantities.

174 The American Geologist. Mate Sees

EDITORIAL COMMENT.
CROLL’S THEORY REDIVIVUS.

Glacialists will read with much interest the discussion of
the climate of Mars by Mr. Percival Lowell, published in the
Proceedings of the American Philosophical Society,* Phila-
delphia.

Twenty-five years ago, when Croll’s theory was tested by
an appeal to the testimony of Mars on the bearing of eccentri-
city on glaciation, it was because Mars presented appearances
suggesting polar ice-caps, and because he is in eccentricity and
tilt favorable to the application of Croll’s theory. It was im-
mediately discovered that Mars, on the assumption that other
conditions were similar to those of the earth, afforded no sup-
port to that hypothesis. One pole showed as large a cap as the
other. Eccentricity therefore did not seem to affect precipi-
tation about the pole.

But since then the examination of the physical conditions
of Mars has proceeded. It has been discovered that the as-
sumption of similarity with the earth was a mistake, and that
Mars presents the opposite of similarity with the earth, “and
with the flight of the similar the cogency of the argument de-
parts.” In the light of this change Mr. Lowell re-opens the
case and proceeds to discuss anew the bearing of the planet
Mars on the hypothesis of Croll.

Accepting the suggestion of Sir William Herschel, that the
white spots that appear on Mars about his poles, are due to ac-
cumulations of ice and snow, and noting that they increase al-
ternatingly and diminish again “in a certain chronometric ca-
dence,’”’ he confronts at once the theory that those spots are due
rather to congealed carbonic acid, for carbonic acid in extreme
cold not only assmues a solid form, but that form is as white
and delicate as snow. He calls attention to the reluctance of
carbonic acid to remain in a liquid form. It passes almost im-
mediately from a solid to a gas. There are, however, certain
features that appear about the margins of those white caps
that show rather plainly that they disintegrate as they shrink,
giving rise to belts and bays of different color. These mar-
ginal features behave precisely as if they were affected by the

* Op. cit., vol. 39, Oct.-Dec., 1900.

€ ~
Croll’s Theory Redivivus. 175

variations of the seasons, and are hence due to changes of
temperature, and are to be attributed to the same cause or
causes that produce the increase and diminution of the white
spots. Water is the only known substance that will remain in
the form of liquid sufficiently long and in sufficient quantities
_ to answer all the conditions. Certainly it will not be allowed
to assume an ocean nor rivers of liquid carbonic acid.

The state of things seems to be this: so soon as either cap begins
to shrink, there proceeds to surround it a blue belt. The belt increases
with the increased rate of diminution of the cap and decreases as that
diminution falls off. Meanwhile it keeps pace with the cap, shrinking
with it so as to always border its outer edge.

It is difficult to conceive how anything could more poacligtene pro-
claim itself the liquid product of the disintegration of the cap. This
badge of blue ribbon seems to mark the substance as H:20O.

To this conclusion, however, there are two drawbacks.
One consists in the less heat received by Mars from the sun,
which, as compared with the earth, distance for distance, would
be only a moiety, and would interfere with any assumption of
H,O in liquid state on Mars in such large quantity. The other
is a thinner air at the surface than we know, and therefore the
absence of a blanketing atmosphere to keep out the cold of
space. But these objections are not fatal to the assumption
that the liquid substance that follows the margin of the white
cap consists of water.

In the first place the greater amount of clouds and vapor
of water in the earth’s atmosphere causes the earth to reject
a far greater proportion of the sun’s heat. Much of the sun’s
heat intercepted by the earth does not reach its surface, quite
apart from what is necessarily reflected. But the Martian sky
is clear from clouds, perpetually. “All the heat a pure sky per-
mits to pass falls unhindered upon the soil. Thus receptivity
makes up what distance denies.”

Secondly, the earth’s blanket consists not in its atmosphere,
contrary to what has been thought, but in the watery vapor that
it contains. This has been shown by Tyndall. He stated that
on an average day in England the atmospheric vapor of water
exerts a hundred times as much reaction against the sun, and
hence against the cold of space, as the atmosphere itself. Mr.
Lowell concludes that if one seventieth part of the Martian at-
mosphere is watery vapor, and the atmosphere one-seventh of

A
176 The American Geologist. March, 2900

our own at sea level, it may render as effective a covering as
our own. While not affirming that this is the case, he notes
simply “how little we need go out of our way in possibilities
to furnish Mars with a sufficient covering.”

After sufficiently showing that these phenomena on Mars
are due to ice and snow about the poles, and to the produc-
tion of water as the caps recede, Mr. Lowell notes some pe-
culiarities by which they differ from the snow caps of the earth.
In many respects they are comparable and similar, but ours
have greater extension, reaching, in the northern hemisphere,
in their maximum, southward to about the latitude of 45°, pro-
ducing a snow-spot about 9go° in diameter. It would thus ap-
pear to an outside observer. “In this we live and move and
have our being for some four months, and it is at least a preg-
nant thought that to such an outsider the highest development
of life upon our planet should seem thus for nearly half the
year to have its existence within the polar cap.” From this
maximum our snow cap, as viewed from Mars, would appear
to dwindle till, about two months after the summer solstice,
it would measure only about 40° across. The southern cap,
from incomplete data, seems to be larger than the northern,
both at maximum and at minimum.

On Mars the northern snow cap has a maximum of 70’,
about 53 of its own days after winter solstice. It recedes then
to a minimum of 3° which occurs about the same time after the
summer solstice, and it retains the minimum size some time.
Comparing therefore the northern caps of the two planets, it is
apparent that that of the earth is greater than that of Mars at
each extreme. As to the maximum this happens in spite of the
fact that the Martian year and therefore the Martian winter is
nearly twice as long as our own.

Again the ratio between the maxima and minima on the
earth are as five to one, while on Mars they are as 130 to one.
“To the belief that Mars lacks warmth this comparison is cal-
culated to give a shock of surprise.”

A still more remarkable contrast exists. This is the differ-
ence in behavior of the two Martian caps. The southern cap
is bigger than the northern in winter and smaller in summer.
It surpasses it in accumulation and again in dissipation. This
can be affirmed, although the data of observation on the
northern maxima are not satisfactory.

Croll’s Theory Redivivus. 177

As to the cause of these differences between the south
polar cap and its counterpart on the north pole Mr. Lowell
shows that, under the law of the radius vector, to which both
gravitation and light, or heat, are amenable, eccentricity can
have no effect; nor axial tilt, since that brings the two hemis-
pheres in turn under the same though varying conditions—as
variant for one as for the other.

“Not the amount of heat but the manner of its reception,
then, is responsible for the differences we observe,” between
the maxima and minima of the Martian snow caps. The differ-
ence between the maxima is rationally attributed to the sur-
passing length of the Antarctic winter, which is 75 of our days
longer than the northern. The total heat received from the sun
by the two hemispheres is the same, but it is intensified in a
short season in the northern. The contrast between the minima
of these snow caps is not so easily explained. The southern
snow cap is more reduced in its short summer than the north-
ern in its longer summer. Mr. Lowell mentions two factors that
spring from the planet itself which may account for this (a)
The more intense diurnal heat of the southern summer pro-
vokes greater volumes of water during its prevalence, and this
adds to the readiness with which the snow cap as a whole could
shrink. (b) The cloudiness at night (for every day is perfectly
clear) is increased by greater daily dissolution of the cap, and
hence the proportion of watery vapor is increased in the south-
ern latitudes of Mars during the summer months. This in-
creased blanket conserves the heat of the day before so that the
following day, and every following day, is reinforced by the
greater proportion of conserved heat. The two conspire to
waste the Antarctic snows more rapidly than the northern. It
appears then that on Mars eccentricity has no tendency to form
a northern ice-cap, or about the pole of that hemisphere that
has its summer solstice near perihelion, but that the permanent
accumulation there is actually less than at the south pole.

In transferring this argument to the earth we are confront-
ed at once with a differing total amount of moisture and the
presence of oceans. This involves greater precipitation, and
the formation of a larger amount of winter ice. Mr. Lowel!
shows that under increasing precipitation the Antarctic minima
increase, relatively to the Arctic, faster than the Arctic, anid

178 The American Geologist. March, 1200";

hence that they finally reach and surpass the Arctic minima. In
other words with precipitation increased equally over the whole
planet the size of the perpetual ice-cap over the southern pole
would finally surpass that about the northern one. ‘Whereas,
then, with moderate precipitation the hemisphere with the ex-
tremes of summer and winter climate would have the less per-
petual ice of the two; with more precipitation the result would
be reversed. * * * Thus a glacial period might be pro-
duced with us under the very same conditions which would bar
it on Mars. It would come about in consequence of the ec-
centricity of the orbit, but not chiefly because of that eccentrici-
ty. Rather we may say, because of the amount of moisture
capable of being manufactured. For were the moisture to fall
below a definite amount, not only would no glacial period re-
sult, no matter what the eccentricity, but actually a sort of
anti-glacial epoch would be brought about by that very same
cause.”

“Our survey of the Martian polar caps, then, leads us to
some curious conclusions. It starts with apparent contradic-
tion of Croll’s theory to end in final confirmation of it. It
comes to curse and stops to bless. But it does more. It
shows that eccentricity of orbit by itself not only causes no un-
iversal glaciation, but actually produces, on occasion, the op-
posite result in more than offsetting by summer proximity what
winter distance brings about. Eccentricity needs water, and
a great store of it as handmaid before its glacial work can be
accomplished. Could our earth but get rid of its oceans, we,
too, might have temperate regions stretching to the poles.”

The vast blue-green areas of Mars are interpreted as grassv
plains or forests. They prevail in the southern hemisphere.
They wax and wane with the season, slightly changing their
color. The dark bands that cross them are perhaps channels
filled with slow running water derived from the annual dis-
solution of the southern snow caps, wasting away toward the
tropics.

The eccentricity of the southern snow cap, which is marked
from maximum to minimum, is supposed to be due to a de-
pressed area, rather than to elevated lands. In this depression
the permanent ice accumulates in greatest quantity, and sur-
vives through the intense summer. N. H. W.

Review of Recent Geolo gical Literature. 179 -

REVIEW OF RECENT GEOLOGICAL —
LITERATURE.

Contributions to the Tertiary Fauna of Florida. By Witt1AM HeEa-
LEY Datt, A. M.
Part V. of the Contributions to the Tertiary Fauna of Florida by

professor Dall is at hand in Part V. vol III., of the Transactions of |

the Wagner Free Institute of Science of Philadelphia. The publi-
cation bears date December, 1900. The present contribution deals
with the Teleodesmacea: Solen to Diplodonta, and is a continuation
of the work on the Tertiary fauna appearing in the previously issued
publications of the Institute. It was found impossible to complete
the discussion of the large family Veneride for publication in its
appropriate place in the present part of the volume, and so it is de-
ferred till the publication of the next part which it is believed will
contain all that remains to be written to finish the subject. Some

work on the Tertiary shells of Florida was published in volume I

of the Transactions of the Institute, but it remained for professor

Dall, in volume III. to take up the study of this most prolific and in-

teresting fauna with a thoroughness that could not previously have

been attempted. The fact that there are nearly 140 new species in
the present part will give some idea of the practical newness of
the field which professor Dall has so successfully cultivated, and of
how little was really known about it when the author began his
studies. Every such thorough-going contribution, dealing exhaus-
tively with a single fauna, marks a real advance; it brings a whole
new field within the known province of Paleontological science.

Si. &

Geology of the Boston Basin; vol. 1 part ut. The Blue Hills Com-

plex; by Witt1am O. Crossy. (Occ. papers, Bos. Soc. Nat. Hist. ;

pp. 289-964, pls. 15-39, No. 4, 1900.)

This paper completes the detailed study of the southern edge of
the basin, carried on so long and well by Prof Crosby, from the
Atlantic coast west to the valley of the Neponset. The author de-
fines the complex as “the area of granitic and associated Cambrian
strata which includes the Blue Hills proper, and extends thence east-
ward across Quincy and the northern parts of Braintree and Wey-
mouth.” It is a distinct geological unit.

The Cambrian strata occur largely on the north and south mar-
gins of the area, and consist of fine, poorly bedded slates, which
are thought to have been deposited in a quiet area of some depth,
one shore of which was perhaps to the northwest. The base of
these slates is nowhere exposed. Prof. Crosby believes, although
upon what data is not made clear, that the quartzytes northwest of
the basin and the limestones of Shoreham and Newbury are lower
Cambrian; and from that time continuous deposition occurred,
through the middle Cambrian and a now denuded upper Cambrian

180 The American Geologist. Merck; 2

series. Probably, also, sedimentation was prolonged through the
Ordovician, and the detritus has since been removed.

Not later than early Devonian time the strata had been sharply
folded, and were intruded by an igneous series almost entirely acid.
The theory advanced for its origin is melting of the base of the
slates, due to the blanketing effect of prolonged deposition; and
formng an acid magma above the abyssal basic one. No estimate of
the thickness of this stratified cloak is given; but to produce the
existing effect there would be required a depth of sediment far
greater than we have any warrant for inferring, and especially, such
view seems inconsistent with the almost surface character of the
igneous mass, not only near its summit but far down the sides, as
exhibited in the aporhyolytes. It is much more probable that the
intrusion burst through the base of the Cambrian series

In cooling, the batholith became differentiated both in texture and
composition, being finer and more basic toward the periphery. For
explaining the latter, the author uses Becker’s theory of fractional
crystallization. The results are two types of granites, biotitic and
hornblendic, forming the main mass; and at the margins three
phases, dioryte, fine granite, and aporhyolyte, the last grading into
the granite. The later stages of refrigeration were apparently ac-
companied by further dike intrusion of granite, and dikes and flows
of aporhyolyte.

The Carboniferous sediments, which make up a large part of the
present basin, are thought to be really one formation, deposited
delta-like, during slight oscillations; and while coal was being de-
posited elsewhere, the bottom here was too deep. This last con-
clusion is not borne out by the fossils discovered recently by Messrs.
Burr and Burke; nor by the large amount of coarse sediment present,
much of which can be proved to have traveled but a short distance.
Very likely the reason is to be sought rather in the almost open-coast
conditions, by which the sea action was too rigorous. The melaphyr,
which is so characteristic of the southern part of the basin, is con-
sidered as a series of contemporaneous flows, and never intrusive.
It may be pardoned, perhaps, if some students of the region still re-
gard the evidence as pointing to intrusion.

The Appalachian revolution gave the present structure to the
basin as a whole, which, however, then extended far beyond its pres-
ent limits. The larger faults, particularly on the margin, result each
from two disturbances—one during the deposition of the Carbonifer-
ous sediments, the later at the close, during the general orogenic ac-
tion. The result, according to Prof. Crosby’s interpretation, is a
graben of sediments between two crystalline walls.

As far as know, the region has been above sea level since Car-
boniferous times, except during a portion of the Pleistocene.
Erosion has removed the strata on either side of the graben, and
much of the complex and basin. The granite has proved less re-
sistent than the aporhyolyte, and the slate than either. The Blue

Review of Recent Geological Literature. 181

Hills mark the level of the Cretaceous peneplain, dominant farther
inland. Below this is a “coastal peneplain,’ which rises westward
and bevels off the earlier and higher level. Below this, again, is the
basin. The discussion of the surface geology presents nothing new,
in the chief author’s part. This is followed by a paper entltled ‘Lake
Bouvé, an extinct glacial lake in the southern part of the Boston
Basin,” by Dr. A. W. Grabau. An entirely separate chapter closes
the work, on the “Paleontology of the Cambrian terranes of the
Boston Basin,” also by Dr. Grabau. Both papers are full, containing
new material as well as a summary of existing knowledge; and they
should be reviewed separately.

Altogether, this third part of the Boston Basin papers is a not-
able contribution on a difficult field; and shows most pains-taking
labor. It is much to be regretted that the society has not completed its
publication by issuing the geological map of the area which, the
text states, accompanies the report. Also, the great care shown in
gathering the field details does not appear to have been extended
to all parts of the make-up of the paper. There is neither table of
contents nor index, nor list of illustrations; nor is there any ref-
erence in the title to the two important contributions of Dr. Grabau.
More summaries scattered through the work would prove a help, and
the igneous part suffers much from almost an absence of chemical
analysis. In places, too, theory is presented before evidence, and the
two are not always dissociated clearly. The illustrations are excel-
lent, the photographs being reproduced by gelatine process, and the
original drawings of fossils successfully treated in the same way.

J, Ew:
Notes on the Tellurides from Colorado. By CHARLES PALACHE. (Am.

J. Sci., 160, 419-427.)

The article gives the results of a careful and admirable crystal-
lographic study of the mineral sylvanite together with a chemical inves-
tigation of the same. The analyses show the composition to be repre-
sented by the formula Au Ag Tex, thus confirming the conclusions pre-
viously reached by Pearce from analyses made by him on massive
material from Cripple Creek. The goldschmidtite of Hobbs is shown
by Dr. Palache to be identical in crystallization with sylvanite. Owing
to this identity it is thought that the analyses made by Hobbs may
have been rendered inaccurate by the extremely small quantity with
which he worked, and in a note incorporated in the article, Prof.
Hobbs withdraws the name goldschmidtite as representing a distinct
species. The article is concluded by a note on the crystal habit of
hessite from Boulder, Colorado. Cc. H. W.
Mohawkite, Stibio-Domeykite, Domeykite, Algonodite and some arti-

ficial copper arsenides. By Grorce A. Koenic. (Am. J. Sci., 160,

439-448. )

The copper arsenides occurring in the Keweenaw copper formation
of Michigan are found only in veins intersecting the bedded deposits
of native copper, and have so far, been observed only near the foot of

182 The American Geologist. March, T00L

the formation toward the south-east. The new mineral mohawkite oc-
curs in a vein at the Mohawk mine associated with other copper arsen-
ides in a gangue of quartz and calcite. The mineral is massive, struct-
ure granular to compact, color a gray tinged with yellow taking readily
a brassy to purplish tarnish. It is brittle, hardness about 3.5 with a
specific gravity of 8.07. A chemical analysis gives its composition as
follows: Cu=61.67, Ni=7.03, Co=2.20, Fe= trace, As=28.85, which
gives the mineral the formula (Cu, Ni, Co)sAs. The author shows
also that nickel and cobalt are present in small quantities in the mineral
domeykite CusAs, and, that the specific gravity of the latter should be
7.94 instead of 6.7 to 7.5 as given by the mineralogies. By volatilizing
arsenic over red hot copper in a combustion tube sealed at one end two
arsenides were obtained, one having the composition CuzAs and _ re-
sembling chalcocite, the other consisting of groups of minute crystals
and identical with domeykite in composition. By the name stibio-
domeykite the author designates a mineral from the Mohawk mine
closely resembling domeykite but containing a small percentage of
antimony; and by the name .mohawk-whitneyite a very intimate mix-
ture of the two minerals mohawkite and whitneyite. The results of
several analyses of these last mixtures accompany the article. The cor-
rectness of the formula (Cu Ni Co)«sAs, which was assigned to mo-
hawkite by Dr. Ledoux and reported in the April number of the Min-
ing Journal for 1900, is strongly denied by Dr. Koenig. He concludes
his paper with a new analysis of algodonite, confirming the formula
CucAs. Its specific gravity was found to be 8.383 instead of 7.62 as-
previously given. CAHEaWe

The analyses of Italian volcanic rocks. By H. S. WasHincton. (Am.

J. Sci., 159, 44-45)

Analyses are given of the following types of rocks: ciminyte, from
Monte Cimino, Viterbo; mica trachyte (selagyte), from Monte Catini,
Tuscany; andesyte, from Radicofani, Tuscany; leucityte, from Capodi
Bove, Alban Hills. A discussion is made of the analyses, the miner-
alogical composition of the rocks and their classifications in accord-
ance therewith. Cc. H. W.
Occurrence of native lead with copper and other minerals at Franklin

Furnace, N. J. By W.M. Foote. (Am. J. Sci. 156, 189-188.)

Small irregular masses of lead I to 2 mm. in diameter, associated
intimately with native copper and a variety of minerals—among them
axinite, garnet, willemite and phlogopite—have been found on a few
specimens taken from the 800-foot level of the Parker shaft on North
mine hill. The rarity of native lead and its associations at Franklin
make the discovery interesting. Cc. H.W.
Occurrence of sperrylite in North Carolina. By W. E. Hrppen. (Am.

J. Sci., 156, 380-381.)

The mineral sperrylite a di-arsenide of platinum—is described from
Macon county, N. C., where it was discovered in the sands of Cowee
creek, associated with a little gold and the minerals monazite, zircon
and menaccanite. The sperrylite consisted of a few very minute, nug-

Review of Recent Geological Literature, 183

get-like particles and crystals, the latter showing the combination of
the cube and octahedron. Cc. H. W.
Thomsomte, mesolite and chabazite from Golden, Colorado. By Hor-

ACE B. Patron. Bull. Geol. Soc. Am., vol. 17, pp. 461-474. pls.

43-49.

The paper gives a detailed description, supplemented by excellent
plates, of the occurrence and habits of the above named zeolites, found
in a scoraiceous band of the basalt flow which caps what is known as
Table mountain near Golden. Cc. H. W.
Beitrage zur Burtheiling der Brachiopoden. Von Dr. F. Huene,

(Centralblatt fur Mineralogie &c., 1901.)

This pamphlet is a critical review of the studies of F. Blochmann
on the Brachiopoda, and a comparison of his results with those of
Beecher and Schuchert.

The part of these studies so far published refer to Discina, Dis-
cinisca Lingula and Crania and they bring to light some important
characters in the morphology of the Inarticulata not heretofore rec-
ognized. The reviewer lays considerable stress upon an important dis-
tinction between the Articulata and Inarticulata in the properties of the
pedicle. In the latter division the motions of the pedicle are auto-
matic and it has no attached muscles, in the former the pericle itself is
immobile, and its motions are governed by muscles attached within
the shell.

Another important point brought out by Blochmann is that the
opening of the valves in the Inarticulata is effected by the contraction of
the “Cutanei” or muscles of the body-wall which by squeezing the
viscera and cavity in which they are contained, force the valves apart;
he claims that the internal muscles have very little power for this
purpose.

Another important observation of Blochmann is that the pediclé is
a continuation backward of the ventral valve, and is in organic con-
nection with it; the supporting substance of the pedicle within its
cuticle being an extension of the body-wall of the brachiopod.

Blochmann finds that the circulation of the mantle in the sinuses
&c. is of a respiratory nature, and shows how the observations of
Morse of two inlet and one outlet current in Lingula are in accord-
ance with his observations. There is no venous circulation in these
passages, the blood being contained in tubes of microscopic size.

The notation for the muscles in Blochmann’s work differs from
that lately current in English literature. The only laterals recognized
are the “j” laterals; the other laterals with the transmedians are
“oblique.” As the pedicle is automobile, no muscles are required for it
within the shell, and the connected threads are “nervi.”

The observations in this review are made more instructive by a
number of figures in the text, cited from Blochmann’s work, and
showing the various points of structure discussed in this review.
Dr. von Huene directs deserved attention to the important work of
Beecher and Schuchert on the classification and morphology’ of the

184 The American Geologist. Marches

Brachiopoda, though he lays a strong emphasis on the distinction be-
tween the “Ecardines” and “Testicardines” (=—Inarticulata and Articu-
lata. ) GUM)
Kleine paleontologische Mittheilungen. von Dr. F. HuENE in Tiibingen,

mit 2 Taf. (Neu Jarb. fiir Mineralogie &c, 1901, Bd. I, s. 1-8.)

In this article Baron v. Huene describes a new species of Medusa
(Medusina geryonides) from the Murchisonia slate of Wiesenteig in
Wurtemburg of which the preserved impression exceeds an inch in
diameter and is quite distinct and characteristic.

He also gives figures and a descripion of a new Cycad (Zamites
infraooliticus) from the Blagdini zone near Langenbruck in Switzer-
land. The oroginal of this species is in the museum of Lausanne.

G. F. M.
Action of Ammonium Chloride upon Analcite and Leucite. By F. W.

CLARK AND STEIGER. (Am. J. Sci., 159, 117-124.)

The article records the results of an investigation on the action of
ammonium chloride upon the minerals analcite and leucite when the
latter are heated separately with this reagent in sealed tubes at 350°C;
also the meaning which the results obtained have in regard to the
chemical constitution of the two minerals. Both minerals suffer a
substitution of their alkali by ammonium, yielding the same compound
whose composition is that of an ammonium leucite, NH.AISi.O¢. This
fact is believed to indicate an original similarity in the two minerais
which is also borne out by crystallographic and other resemblances.
A further study of the chemical properties of the ammonium derivative
leads the authors to think that analcite and leucite are not true metasili-
cates but either salts of a polymeric metasilicic acid or a mixture of
ortho and tri-silicates. Cc. H. W.
Chemical Study of the Glaucophane Schists. By H. S. WaAsHINGTON.

(Am. J. Sci., 161, 31-59.)

A consideration of the chemical and mineralogical composition of
the above class of metamorphic rock as shown by a series of admirable
chemical analyses of specimens from some seven localities, leads to
conclusions concerning their classification and origin which are briefly
and concisely given by Dr. Washington in his summary as follows:
“The Glaucophane schists belong to two main groups, sharply sepa-
rated from each other. The larger one is basic, composed chiefly of
glaucophane and epidote, often with abundant garnet, zoisite, diallage,
and sometimes smaller amounts of mica, feldspar and quartz, and rutile
and titanite as frequent accessories. Chemically these closely resemble
the composition of the rocks of the gabbro family, and are apparently
divisible into two sub-groups, one high in CaO, the other low in it.
These are in most cases almost undoubtedly derived from such
igneous rocks or their tuffs, but also possibly in rarer cases from
sediments or slates of similar composition. These basic glaucophane
schists scarcely differ in composition from the amphibolites and
eclogites, and the difference in their formation is probably to be
ascribed to differences in the conditions of metamorphism. A smaller

Review of Recent Geological Literature. 185

but widely spread, group is acid in composition, and these are com-
posed largely of quartz and glaucophane, with mica and sometimes
albite. These are derived from cherts, quartzites or quartzose shales
and sandstones. The existence is indicated of a third, still smaller
group of intermediate mineralogical composition, and chemically like
the diorites. The glaucophane schists are apparently the result of
both regional and contact metamorphism, and in many regions they oc-
cur together. This last seems to be the rule in glaucophane schist
areas of any size, and where only the one kind is found the area is
apt to be small.” Cc. H. W.

The Mode of Occurrence of Topaz Near Ouro Preto, Brazil. By Or-

VILLE A. DersBy. (Am. Jour. Sci., 161. 25-34.) ;

The article gives the results of a study of the associated earths
and rocks where the topaz is found. The mineral itself is found in a
dark-colored earth, thought, from its mineralogical character and its
geological relations, to represent the remains of an igneous dike in
which the topaz was an original mineral. What the exact nature of
the igneous dike was cannot be told on account of its state of ex-
treme alteration. Cc. H. W.
Carnotite and Associated Vanadiferous Minerals in Western Colorado.

By W. F. HILLesranp and F. Lestre Ransome. (Am. J. Sci., 160.

120-144.)

The paper embodies the results of investigations concerning the oc-
currence and nature of the uranium and vanadium ores of western
Colorado. A somewhat detailed description of the various ore de-
posits is given by Dr. Ransome from a study of the region made by him
and Dr. A. C. Spencer. He concludes that the ores are recent im-
pregnations in the sandstones. The chemical researches made and re-
corded by Dr. Hillebrand furnish, not only valuable data concerning
the composition of the ores and their constituent minerals, but afford
the chemist excellent descriptions of the analytical methods involved
in the analysis of the uranium and vanadium ores. The summary made
by the authors is as follows: “The body called carnotite is probably a
mixture of minerals of which analysis fails to reveal the exact nature.
Instead of being the pure uranyl-potassium-vanadate, it is to a large
extent made up of calcium and barium compounds. Intimately mixed
with it and entirely obscured by it is an amorphous substance—a sili-
cate or mixture of silicates—containing vanadium in the trivalent state,
probably replacing aluminum. The deposits of carnotite, though dis-
tributed over a wide area of country, are, for the most part, if not
altogether, very superficial in character and of recent origin. The
green coloring and cementing material of certain sandstones near
Placerville, Colorado, is a crypto-crystalline alumino-vanadio-potassium
silicate resembling roscoelite, but with the percentage proportions of
Al,0; and V.O; reversed. It constitutes over 25 per cent. of the sand-
stone at times, and contains nearly 13 per cent. of V:Os, the latter
amounting in the maximum case observed to 3.5 per cent. of the sand-
stone. As yet these highly vanadiferous sandstones have been found

186 The American Geologist. March, 1901.

only at Placerville, where it is intended to work them for vanadium.
Carnotite is associated with them in only trifling amount. Other sand-
stones noticed owe their bright green color to chromium. In yet anoth-
er case where the color was dull green, this was not due to either
chromium or vanadium. 3 C, Ei We
A Contribution to the Natural History of Marl. By Cartes A.

Davis. - (Jour. Geol., 8, 485-497.) :

This valuable contribution to the chemistry of marl is based upon
observations made in certain small lakes in Michigan; but the prin-
ciples which it embodies undoubtedly admit of general application.
The marl is nearly pure carbonate of lime, the source of which is to
be sought in the solution by meteoric waters of limestone or other cal-
cerous strata, the drift of limestone districts and, more remotely, the
carbonation of lime-bearing silicates. The real problem is the depo- ~
sition of this dissolved carbonate of lime in the form of white chalky
marl, which consists only to a small extent of shells or fragments of
shells. After pointing out the inadequacy of animal life, evaporation
and escape of’ carbon dioxide on relief of pressure, as causes of the
precipitation of the carbonate of lime, the author discusses at length
the only alternative hypothesis, namely, that the calcium salts are pre-
cipitated through the agency of plant life. In the marly lakes aquatic
plants of all kinds become incrusted with calcium carbonate, which is
not a true secretion of the plants, for it is purely external, and the
same species in other districts are not incrusted. The deposit is formed
incidentally by chemical precipitation upon the surface of the plants,
probably only upon the green parts, and in performance of normal and
usual processes of the plant organism. All green plants inhale carbon
dioxide and exhale oxygen; and these are two possible causes of the
calcareous incrustation. If the calcium carbonate is in excess in the
water and is held in solution by carbon dioxide, then the absorption
of the latter by the plants causes precipitation of the carbonate upon
the parts (stems and leaves) abstracting the gas. But if the proportion
of calcium corbonate in solution is so small that it would not be de-
posited even if there were no carbon dioxide present, the precipitation
is explained by the action of the oxygen set free by the living plants
in converting calcium bicarbonate to monocarbonate:

CaH, (CO,),+O=H,0+CaCO,+CO,+0.

Plants vary greatly in their power of precipitating the calcium car-
bonate; and the algae, and especially the Characes or stoneworts, are
most efficient. Analyses are given showing that plants may precipi-
tate mineral matter equal to several or many times the weight of their
own dried tissues, that this mineral matter consists of CaO,, 93.76;
MgCO,, 2.93; SiO,, 2.40; and iron and aluminum oxides 0.89 per cent.
It is shown that the structure and distribution of the marl are entirely
in harmony with the view that a species of Chara is an important
agent in its formation; but it is recognized that a species of Zonotrichia
has always played an important part, explaining, especially, the more
solid and nodular forms of the marl. W. 0. C.

Review of Recent Geological Literature. 187

The Composition of Kulaite. By Henry S. WasuincTon. (Jour.
Geol., 8, 610-620.)

Kulayte is the name given by the author several years ago to a
subgroup of the basalts in which hornblende occurs as an essential con-
stituent and surpassing augite in quantity and importance. The orig-
inal analysis by Rohrig showed, for basalts, abnormally high soda, as
well as very high alumina and low magnesia. There seemed to be no
mineral present which would account for the high alkalis, and to de-
termine this and other points two new analyses were undertaken, one
of normal kulayte, and the other of a leucite kulayte. The first showed
in comparison with R6hrig’s analysis, about two per cent. more Be.0;
and as much less K,O; and the second differed rather widely except for
the MgO, CaO and Al,O,. It is surprising to find that all these dif-
ferences are regarded a probably due to the different analytical
methods used. The normal and leucite kulaytes are found to agree
closely except in the minor constituents TiO, and PO) ; and the author
next considers the place in the classification indicated by this composi-
tion. The alkalis and alumnia are shown to be high for a true basalt;
and for these reasons and also becuse of the higher SiO, and the lower
iron oxides, MgO and CaO, they cannot be referred to the subgroup of
hornblende basalts. They are, in fact, properly leucocratic, while the
hornblende basalts are melanocratic; and the closest analogues of the
Kala rocks are to be found among the nepheline-tephrytes and the
nepheline-basanytes, notwithstanding that many of these are markedly
lower in SiO,, Al,O,, and Na,O. A resemblance to the monchiquytes
is also noted, the main difference being the higher H,O content of the
latter. Except in the glassy varieties, the essential hornblende has been
partially or entirely altered to hypersthene, diopside and magnetite,
The component minerals are calculated from the analysis, and
nepheline, the presence of which was indicated by the gelatinization
and fuchsine tests, is fully confirmed. Certain anomalies of the miner-
al composition, such as a large proportion of orthoclase in the more
basic type, and of leucite in the type running highest in SiO, and low-
est in K,O, are explained by reference to difference in pressure and
rate of cooling; and the author favors basing the classification of this
and other rocks directly upon the chemical composition. W. 0. C.

A Topographic Study of the Islands of Southern California. By W.
S. TANGIER SMITH. (Bull. of the Department of Geology, Univer-
sity of California, vol. 11, pp 179-230, 1900.)

The islands described in this bulletin were studied principally from
maps, and the conclusions reached are intended to be rather pre-
liminary and suggestive than final in character. The topographic fea-
ture of the islands are outlined and a general discussion given of the
characteristics of the various kinds of shore terraces and of the con-
ditions leading to their formation.

There follows an interesting account of the oscillations of the Pa-
cific coast in Miocene and Pliocene time. The information in this ac-
count is not new. The principal point which the present paper aims to

188 The American Geologist. March, 1901.

establish is that the most recent general movements have been the same
for the islands as for the coastline of southern California. 1. H. 0.
A Remarkable Marl Lake. By CuHartes A. Davis. (Jour. Geol., 8,

498-503. )

This paper supplements the preceding, describing the truly im-
pressive deposit of marl in Littlefield lake, Isabella county, Michigan,
and showing that it is unquestionably due to the precipitating agency
of Chara and Zonotrichia, chiefly through the exhalation of oxygen.

W. 0. C.

CORRESPONDENCE.

NoTEs ON THE KANSAS-OKLAHOMA-TEXAS GypsuM HiILts.—From
the time of the earliest explorations of the great plains the gypsum
hills have been objects of particular interest. Long and Marcy,
among early explorers, and Hay, Cummins, Cragin, Prosser and
Grimsley, among later geologists, have written extensively concern-
ing these very interesting formations. Conspicuous on account of
topography, color and position, these hills have ever excited an in-
terest both popular and scientific.

Geologically the gypsum hills are a part of the “red-beds” and
are located near the center of that series. The red-beds consist of
more than 2,000 feet of prevailingly red clays, shales and sandstones.
The series extends from near the great bend of the Arkansas river
in southern Kansas across Oklahoma and far into Texas before it
finally disappears beneath the later Mesozoic and Cenozoic deposits.
The age of the rock has long been a mooted question. In Texas it
has been correlated with the Permian. In Kansas and Oklahoma it
was for a number of years classified as Triassic, but the later geolo-
gists have inclined to the opinoin that the red-beds of this region are
of the same age as those of Texas, 7. e., Permian. No fossils have
been found in the Kansas beds and until the past year very few in
Oklahoma. During the summer of 1900, however, the Oklahoma
Geological Survey collected fossils from several localities in the red-
beds. These fossils—vertebrates from the lower part of the series, and
invertebrates from the upper part—indicate that in Oklahoma at least
the red-beds belong to both the Permian and Triassic.

Throughout the entire thickness of the red-beds the rock is
strongly impregnated with mineral salts. In the lower part common
salt predominates. In Oklahoma there are no fewer than four large
salt planes, and numerous smaller ones. In general the salt planes
are confined to a definite horizon. Even among the saliferous hori-
zons gypsum is of frequent occurrence. Seams of selenite and satin
spar are often abundant.

Correspondence. 189

Some 200 feet above the salt beds the gypsum reaches its culmina-
tion. At this horizon there are thick ledges of massive white gypsum
which lie level and extend for long distances across the country.
Ordinarily there are two of these ledges, each from Io to 30 feet thick
separated by 10 to 20 feet of red clay shale. Professor Cragin has
given this massive gypsum the name “Cave Creek gypsum,” from a
creek in Comanche county, Kansas. The lower (and usually thick-
‘er) gypsum ledge he calls the Medicine Lodge gypsum, and the up-
per ledge the Shimer gypsum. The intervening clays are designated
as the Jenkins clays.* It frequently happens, however, that this clay
entirely disappears, in which case the single gypsum ledge is as much
as 50 feet thick. On the other hand in certain sections there are
three ledges of gypsum, a thinner ledge coming in below the Med-
icine Lodge.

The gypsum hills are hills of erosion. The soft clays below the
massive ledges are readily acted upon by water. The ledges them-
selves are relatively much harder and consequently resist erosion,
The slope of the country is to the east, while the ledges lie com-
paratively level. This causes the greater erosion to the east, and
as the underlying clays are removed the gypsum ledges remain as a
cap forming the escarpment of the hills, which rise like a wall from
the level plains to the east. The slopes below this escarpment are
often as much as 200 or 300 feet high, and consist of blood red clays,
sometimes grass-covered but more often barren of vegetation. These
slopes are often covered with selenite crystals, which on a clear day
reflect myriads of light-points and have given to one part of the hills
the characteristic name ‘glass mountains.”

- Throughout the region of the gypsum hills there are numerous
pronounced erosion forms. Deep and narrow canyons, flat-topped
mesas, pinnacles and turrets, mansard mounds and buttes, and nat-
ural bridges and caves may be found in most localities. These forms
ar2 due not only to the solubility of the gypsum ledges but also
to the fact that the underlying clays are so easily eroded. The
gypsum caves are of particular interest. They are of all sizes from
mere cracks in the rock to immense caverns a mile or more in
length with sometimes dozens of chambers leading off in all direc-
tions. In southern Kansas and northern Oklahoma many of these
caves are known locally as “bat caves” from the fact that they are
the home of multitudes of bats. These animals remain inside during
the day and in the evening pour out of the mouth of the cave in a
continuous stream, sometimes for an hour at a time.

The gypsum hills extend in a general northeast and southwest
direction for a distance of nearly 500 miles from southern Kansas
to west-central Texas. The northern limit so far as I have been able
to observe is in northwestern Barber county, Kansas, on the north
bank of the Medicine river, near Sun City. From this point the hills
trend southeast and approach within six miles of Medicine Lodge,

* Colorado College Studies, vol. vi, March, 1896, pp. 27-39.

190 The American Geologist. March, 1901.

where a bold outlier east of the main line of hills overlooks the valley
of the Medicine river. The line of hills crosses the Salt Fork at the
state line and approaches the Cimarron in the northeastern part of
Woodward county, Oklahoma. Throughout nearly its entire course
in this county, a distance of 40 miles the Cimarron flows in a nar-
row valley enclosed between the hills. In places the valley is little
more than a canyon with precipitous walls too feet or more in hight.
The gypsum hills trend southeast along the south side of the Cim-
arron as far as the Glass mountains in southern Woods county, and
then gradually retreat from this river and approach the North
Canadian near El Reno. From this point at which the hills find
their most eastern limit, they trend southwest across the Kiowa and
Commanche reservation to the Red river. In Texas extensive gyp-
sum deposits occur at Quanah, Hardman county, and in Stonewall,
Kent and Knox counties as far as Sweetwater on the Texas Pacific
railroad.

Throughout this area, from Kansas to Texas, the region of gyp-
sum deposits is from 10 to 50 miles wide and is in all places much cut
up with canyons and streams. Certain parts of the range have received
particular names, as for eaxmple: Glass mountains, Chautauqua moun-
tains, Stony hills, Cedar hills and Gray Eagle and Wild Cat buttes. For
the entire range in Oklahoma the name “Marcy” range has been pro-
posed, but it need scarcely be feared that any other name will ever
take the place of the good old cowboy phrase, “Gyp.” hills.

In regard to the economic importance of the gypsum it is but
necessary to add that mills for manufacturing the product are in
operation in all three states in which the hills are found. Of these
perhaps the most important are located at Springvale and Medicine
Lodge, Kansas, Okarche, Oklahoma, and Quanah, Texas. As the
supply of material is inexhaustible it is but a matter of time when
the gypsum from the Gypsum hills will become one of the important
sources of income from the region. CHARLES NEWTON GOULD.

University of Oklahoma, Feb. 1, rgot.

MONTHLY AUTHOR’S CATALOGUE

OF AMERICAN GEOLOGICAL LITERATURE
ARRANGED ALPHABETICALLY,

Abbe, Cleveland, Jr.

The Physiography of Allegany county. (Md. Geol. Sur., Alle-
gany county, pp. 27-54, pls. 1-6, 1900.)
Adams, F. D.

_The excursion to the Pyrenees in connection with the eighth inter-
national geological congress. (Jour. Geol., vol. 9, pp. 28-46, 3 pls.
Jan.-Feb., 1901.)

Author's Catalogue. IQ!

Ami, H. M.

Annual address of the President of the Ottawa Field Naturalists’
club. (Ottawa Naturalist, vol. 14, pp. 197-212, Feb., 1901.)
Anderson, F. M.

The Neocene Basins of the Klamath mountains. (Jour. Geol., vol.
9, Jan.-Feb., 1901, p. 75; Am. Geol., vol. 27, Feb., 1901, p. 131.)
Baker, Marcus

Survey of the northwestern boundary of the United States, 1857-
1861. Bull. 174, U. S. Geol. Sur., pp. 78, map, 1900.

Bassler, R. S. (John M. Nickles and)

A synopsis of American fossil Bryozoa. (Bull. 173; U. S. Geol.
Sur., pp. 663, 1900.)

Bauer, L.A. |

The magnetic declination in Allegany county. (Md. Geol. Sur.
Allegany county, pp. 253-262, pl. 23, 1900.)

Blake, W. P.

' The evidences of shallow seas in Paleozoic time in northern Arfri-
zona. (Jour. Geol., vol 9, p. 68; Am. Geol., vol. 27, p. 130.)
Bownocker, J. A.

The Corning oil and gas field. (Ohio Nat., vol. 1, pp. 49-59, map.
Feb., I901.)

Clark, Wm. B.°

Administrative report [Maryland Geological Survey], containing
an account of the operations of the survey during 1896 and 1897, and
additional legislation. Md. Geol. Sur., vol. 2, pp. 25-42, 1808.)

Clark, Wm. B. (with C.C.O’Harra, R. B. Rowe and H. Ries)

The mineral resources of Allegany county. (Md. Geol. Sur.,
Allegany county, pp. 165-192, pl. 16, 1900.)

Clarke, F. W.
Contributes to Chemistry and Mineralogy from the laboratory of
the United States Geological Survey. Bull. 167, U. S. Geol. Sur.,

pp. 166, 1900.
Clarke, F.W. .

Analyses of rocks from the laboratory of the United States Geo-
logical Survey, 1880-1889. Bull. 168, U. S. G. S., pp. 304.
Claypole, E. W.

The Sierra Madre near Pasadena. (Jour. Geol., vol. 9, Jan.-Feb.,
1901, p. 69; Am. Geol., vol. 27, Feb., 1901, p. 130, 1901.)

Dorsey, C. W.

The soils of Allegany county. (Md. Geol. Sur., Allegany county,
Pp. 195-216, 1900. )

Dresser, John A.

On the Petrography of Mount Orford. (Am. Geol., vol. 27, pp.
14-21, Jan., 1901.)

Dresser, JohnA

Preliminary note on the amygdaloidal trap rock in the eastern
townships of the province of Quebec. (Ott. Nat., vol. 14, pp. 180-182,
Jan., 1901.)

192 The American Geologist. Mazel...

Fairbanks, H. W.

Notes on the Geology of the Three Sisters, Oregon. (Jour. Geol.,
vol. 9, p. 73, Jan.-Feb., 1901 ; Am. Geol., vol. 27, p. 131, Feb. 1901.)
Farrington, O. C.

The structure of meteorites 1. (Jour. Geol., vol. 9, pp. 51-56, Jan.-
Feb., 1901. )
Fassig, O. L.

The climate of Allegany county. (Md. Geol. Sur., Allegany
county, pp. 217-231, 1900.)
Fitch, C. H.

Triangulation and spirit leveling in Indian Territory. Bull. 175,
U. S. Geol. Sur., pp. 141. 1900.
Gannett, Henry ;

Altitudes in Alaska. Bull. 169, pp. 13, 1900.
Gannett, Henry

Boundaries of the United States, states and territories, with an
outline of the history of all important changes of territory (second
edition). Bull. 171, U. S. Geol. Sur., pp. 137, pls. 53, 1900.
Gannett, Henry

The aims and methods of Cartography, with special reference to
the topographic maps now under construction in Maryland by the
United States Geological Survey, in co-operation with the Maryland
Geological Survey. (Md. Geol. Sur., vol. 2, pp. 295-335, 1808.)
Gannett, Henry

A Gazetteer of Utah. Bull. 166, U. S. G. S., pp. 43, map, 1900.

Goode, Richard U.

Survey of the boundary line between Idaho and Montana from the
international boundary to the crest of the Bitterroot mountains. Bull.
170, U. S. G. S., pp. 65, 14 pls., 1900.

Gratacap, L. P.

Paleontological speculations. (Am. Geol., vol. 27, p. 75, Feb.,
IQOI. )
Greene, G. K.

Contribution to Indiana Paleontology. Part vi, pp. 42-40, 4 pls.
New Albany, Feb. 21, Igor. )

Gregory, J. W.

The plan of the Earth and its causes. (Am. Geol., vol. 27, p. 100,
Jan., 1901)
Gregory, H. E. (H. S. Williams and)

Contributions to the Geology of Maine. Bull. 165, U. S. Geol.
Sur., pp. 212, 1900.

Haycock, E.

_ Records of post-Triassic changes in Kings county, N. S. (Trans.
N.S. Inst. Sci., vol. 10, pp. 287-302, map, pl. 1, 1900. )

Hershey, O. H.

On the age of certain granites in the Klamath mountains. (Jour.
Geol., vol. 9, Jan.-Feb., 1901, p. 76.)

Author's Catalogue. 193

Hillebrand, W. F.

Some principles and methods of rock analysis. Bid 270; U.S.
Geol. Sur., pp. 114, 1900.

Hilgard, E. W.

A Sketch of the Pedological Geology of California. (Jour.
Geol., vol. 9, p. 74, Jan.-Feb., 1901; Am. Geol., vol. 27, Feb., 1901, p.
ri)

Hitchcock, C. H.
; The story of Niagara. (Am. Antiquarian, pp. 24, Jan., 1901. )
Hoffman, G. C.

New mineral occurrences in Canada. (Am. Jour. Sci., vol. 11. 9.
149, Feb., 1901.)

Jones, S. P.

The geology of the Tallulah gorge. (Am. Geol., vol. 27, p. 67, 3
pls., Feb., 1901.)

Knight, W. C.

Bates’ Hole. (Jour. Geol., vol. 9, p. 70, Jan.-Feb., 1901.)
Knowlton, F. H. :

Flora of the Montana formation. Bull. 163, U. S. Geol. Sur., pp.
118, 19 pls., 1900.

Lawson, A. C.

A Feldspar-Corundum rock from Plumas county, California. (Jour.
Geol., vol. 9, p. 78, Jan.-Feb., 1901; Am. Geol., vol. 27, p. 132, Feb.,
190T.)

Lawson, A.C.

The Drainage Features of California. (Jour. Geol., vol. 9, Jan.-
Heb., 1901, p: 77; Am. Geol., vol: 27, Feb., 1901, pp. 132.)

Lord, E. C. E.

Report on the Igneous rocks from the vicinity of San Carlos and
Chirpa, Texas. Bull. 164, U. S. Geol. Sur., pp. 88-95, 1900.

Lowell, Percival

Mars on Glacial Epochs. (Pro. Am. Phil. Soc., vol. 39, pp. 641-665,
Oct.-Dec., 1900.)
Lyman, Benj. S.

Sica of Ground Water. (Jour. Frank. Inst., Oct., 1900
I5 pp.
Lyman, Benj. S.

The importance of topography in geological surveys. (Min. &
Met. Jour., Dec. I, 1900, vol. 23, p. 67.)
Matthew, Geo. F.

Acrothyra; a new genus of Etcheminian brachiopods. (Bull. Nat.
Hist. Soc. N. Bruns, No. 19, 1901, p. 303.)
Matthews, E. B.
_ An account of the character and distribution of Maryland build-
ing stones, together with a history of the quarrying industry. (Mary-
land Geol. Sur., vol. 2, pp. 125-241, pls. 7-32, 1898.) ;
Matthews, E. B.

Maps and mapmakers of Maryland. (Md. Geol. Sur., vol. 2, pp.
337-488, 1868. )

194 The American Geologist. Maxphy Aye

Merriam, J. C.

A geological section through the John Day basin. (Jour. Geol.,
vol. 9, Jan.-Feb., 1901, p. 71; Am. Geol., vol. 27, Feb 1got, p. 132.)
Merrill, Geo. P. eo

The chemical and economic properties of building stones. (Mary-
land Geological Survey, vol. 2, pp. 47-123, 1898.)

Newell, F. H. .

The Hydrography of Niteaane county. (Md. Geol. Sur., Alle-
gany county, pp. 233-251, pls. 18-22, 1900.)

Nickles, J. M. (and R. S. Bassler)

A synopsis of American fossil Bryozoa, including bibliography and
synonymy. Bull. 173, U. S. Geol. Sur., pp. 663, 1900.
O’Harra;G:.'c: jy

The Geology of Allegany county. (Geol. Sur., Md., Allegany
county, pp. 57-163, pls. 7-16, 1900.)
O’Harra, C.C.(Wm B Uark, R. B. Rowe and H. Ries)

The mineral resources of Allegany county. (Md. Geol. Sur.,
Allegany county, pp. 165-192, pl. 16, 1900.)

Penhollow, D.P.

A decade of North American Paleobotany. (Science, vol. 13, p. 161,
Feb. I, 1901.)

Purdue, A. H.

Valleys of solution in northern Arkansas. (Jour. Geol., vol. 9, pp.
47-50, Jan.-Feb., 1901.)

Ries, H. (Wm. B. Clark, C. C. O’Harra, and R. B. Rowe.)

The mineral resources of Allegany county. (Md. Geol. Sur.,
Allegany county, pp. 165-192, pl. 16, 1900.)

Sardeson, F. W.

Problem of the Monticuliporidae, 1. (Jour. Geol., vol. 9, pp. 1-27,
1 pl., Jan.-Feb., 1901.)

Seely, Henry M.

oe Geology of Vermont. (The Vermonter, vol. 5, pp. 53-67, Feb.,
1901.

Simonds, F. W.

The record of the Geology of Texas for the decade ending Dec.
31, 1896. (Trans. Texas Acad. Sci., 1899, vol. 3, pp. 19-296, 1900.)
Smith, James Perrin ae

The larval coil of Baculites. (Am. Nat., vol. 25, Jan., 1901, pp.
39-49.)

Stevenson, J. J.

The section at Schoharic, N. Y. (Annals, N. Y. Acad. Sci., vol. 13,
pp. 361-380, Jan. 12, Igo1.)
Stevenson, Arch. E.

Glacial action in Schoharie valleys (Am. N. Y. Acad: Sci vol
TS pi37ouJan. 12; loots)

Sudworth, Geo. B.

The Forests of Allegany county. (Md.. Geol. Sur., Allegany
county, pp. 263-290, pls. 24-30, 1900.)

Author's Catalogue. 195

Turner, H. W.

The Geology of the Great Basin in eastern California and south-
western Nevada. (Jour. Geol., vol. 9, Jan.-Feb., 1901, p. 73; Am. Geol.,
vol. 27, p. 132, Feb., 1901.)

Vaughan, T. W.

Reconnaissance in the Rio Grande coal fields of Texas. Bull.

164, U. S. Geol. Sur., pp. 100, pls. 11, 1900.
Vaughan, T. W.

The Eocene and lower Oligocene coral faunas of the United States,
with descriptions of a few doubtful Cretaceous species. Mon. 39, U.
S. Geol. Sur., pp. 205, pls. 24, 1900.

Weeks, F. B.

Bibliography and index of North American geology, paleontology,
petrology and mineralogy for the year 1899. Bull. 172, U. S. Geol. Sur.,
Pp. 141, 1900.

Williams, H.S. (and H. E. Gregory)

Contribution to the Geology of Maine. Bull. 165, U. S. Geol.
Sur., pp. 212, 1900.

Williston, S. W.

Dinosaurian genus Creosaurus. Marsh. (Am. Jour. Sci., vol. 11,
p. 111, Feb., 1901)

Wortman, J. L.

The probable successors of certain North American primates.
(Science, vol. 13, p. 209, Feb. 8, 1901.)

PERSONAL AND SCIENTIFIC NEWS.

LAKE SUPERIOR [RON TRADE DURING THE YEAR _ IQOO.
Considering the fact that the close of the century marks also
the end of the first half-century of activity in the iron min-
ing region of lake Superior, the development has been one of
the most astonishing of this wonderful age. It is a short half-
century, too, for no mining of importance could be done until
there was water connection between lake Superior and the east,
and this did not come until 1855. In that momentous year the
first ship canal at the foot of lake Superior was cut and the
Jackson mine began small shipments of ore. For years the in-
dustry was small, it was the day of 8-ton railway cars or, stiil
more primitive, of mule railroads, of 500-ton ships, hand drills,
black powder, open pit mining and the like. It was the day of
beginnings and of small things, in a word. For some years the
product of the lake Superior mines was handled over a mule
tram road to Marquette. Up to ten years later or nearly to
1870 a 700-ton ship was an enormous craft and the loading of
this great ship required two days and its unloading more than
that. Many men of today remember sales of ore at Pittsburg
at $18, or about the price of steel billets now. Instead of. the

196 The American Geologist. Mare oe

tram road there are eight great railways engaged in the ore
business hauling cars loaded with 50 tons each behind locomo-
tives of 240,000 pounds weight. Instead of the 700-ton ships,
those of the beginning of the new century carry 7,000 or 8,000
tons, and instead of consuming four or five days in loading and
unloading they are loaded in two hours and emptied in ten. In-
stead of ten to twelve trips a year they are making twenty to
twenty-five. In connection with this, instead of old time prices
ore is now bringing on lake Erie docks little more than the act-
ual mining cost of early years, and in the past three years has
actually sold when delivered at Cleveland at less than the min-
ing expenses of as late as 1887. Not longer ago than 1871 a
drift was driven at the Cleveland mine at a cost of $100 per
foot. Now it could not cost $15. Nitro-glycerine and power
drills have been the humanizing and civilizing agencies in great
measure, and civilizing these have surely been, for where would
be our supremacy today but for the reduction in costs they
have brought about ?—D. E. Woodbridge in Mines and Miner-
als for February.

Mr. FRANK LEVERETY has completed and submitted for
publication by the U. S. Geol. Sur., his second monograph:
“The Glacial Formations and drainage features of the Erie and
Ohio basins.”

THE FIELD CoLUMBIAN Museum has arranged a course of
nine free lectures to be given in the Museum lecture-hall in
March and April. These are to be illustrated by stereopticon
views: The geological lectures are by Dr. E. R. Buckley and
Prof. Wm. H. Hobbs.

SCIENCE CLUB OF NORTHWESTERN UNIversiTy. At the
meeting of February 1st Prof. U. S. Grant spoke on “Some
methods of geological field work,” and at the meeting of March
tst Prof. A. R. Crook spoke on “‘Minerals of the Chicago area.”

GEOLOGICAL SociETy OF WASHINGTON. The following
was the program of the meeting held February 27th: “Me-
morial of Thomas Benton Brooks,” Bailey Willis ; ““Morpho-
geny of southern Alaska,’ G. K. Gilbert ; “Mountain structure
in the trans-Pecos province,’ Robert T. Hill.

THE GEOLOGICAL SURVEY OF GEORGIA has just issued Bul-
letin No. 1o—A, entitled “A preliminary report on a part of the
iron ores of Georgia, Polk, Barton and Floyd counties.” The
report is made by Mr. S. W. McCallie, assistant geologist.

Mr. F. A. Lucas, geologist of Washington, D. C., who has
been drilling for oil in Texas for about two years, was re-
warded by the discovery, on Jan. 10, of a great oil basin. The
flow of oil at Beaumont is said to be greater than from any
single well ever sunk in the United States. It is estimated by
experts that every twenty-four hours it flowed 20,000 barrels
of oil, and that 150,000 barrels escaped from it before the flow

Personal and Scientific News. 197

could be regulated. It is not an illuminating oil, but is sim-
ilar to that now so abundant at Los Angeles, California.

OIL HAS BEEN DISCOVERED IN THE PHILIPPINES, and is ex-

tracted in Panay, Luzon, Mindanao and other islands. In most
cases it is in a stratum of rock about 350 feet below the surface
The working is done by the natives, but largely with machinery
from America.
_ W. H. WEED, WHO HAS RECENTLY SPENT SOME TIME in
Mexico, has returned to this country, and is now engaged in
the final investigations at Butte, Montana, preliminary to
the publication by the U. S. Geological Survey of an ex-
haustive report upon the economic geology of the Butte dis-
trict. Mr. Weed expects to complete his studies at Butte in
about a year, and will then probably commence the study of
the copper region of New Mexico.

C. W. Ciark, son of U. S. Senator W. A. Clark, of Mon-
tana, has endowed the Chair of Mining Engineering in the
Montana State School of Mines, located at Butte, Montana.
The chair thus established has not yet been filled.

THE ANACONDA CoprpER MINING CoMPANY has presented
to the Montana State School of Mines a rock cutting and a
rock grinding machine of the best make, and equipped with
all accessories. It has also presented to the Museum a speci-
men of chalcocite weighing 3,500 pounds—doubtless the larg-
est of its kind anywhere on exhibition. It was taken from the
Never Sweat mine, one of the Anaconda group at Butte.

THE AMERICAN ASSOCIATION FOR THE ADVANCEMENT
OF SCIENCE will hold its next annual meeting at Denver, Col-
orado, August 24 to 31.

THE AMERICAN INSTITUTE OF MINING ENGINEERS. The
eightieth meeting (being the thirty-first annual meeting) was
held in Richmond, Va., beginning, Tuesday evening, February
19.
Mr. J. Epwarp Spurr, at one time connected with the Min-
nesota Geological Survey, and more recently with that of
the National Government, has been appointed geologist to
the Sultan of Turkey, at a liberal salary and all traveling
expenses for himself and family, and will shortly depart for
his new field of labor, with leave of absence for one year from
the U. S. Geological Survey. It is understood that he is also
to have a share in any discoveries that he may make, and that
he is to be provided with suitable assistants and a body guard
of soldiery. :

May. A. W. VocpeEs, who has been at San Juan since the
Spanish war, has returned to New York, and has his address
at Fort Hamilton.

A BRONZE BAS-RELIEF Of the late Dr. J. S. Newberry has
been presented to Columbia University by his children.

198 The American Geologist. March, 1901.

TRIBUTE TO VicTorRIA. At a postponed meeting of the Ot-
tawa Field Naturalists’ Club held on the 29th day of January,
1901, one week after the death of Her Majesty Queen Vic-
toria, the following resolution was unanimously passed: “In
common with all the sorrowing subjects of His Imperial Ma-
jesty King Edward VII. the members of the Ottawa Field-
Naturalists’ Club desire to express their deep sense of sorrow
and loss at the demise of their beloved Sovereign Lady, Queen
Victoria, during whose glorious reign of sixty-four years,
scientific work and research, such as our Club aims to accom-
plish, have received unprecedented impetus.” At the last meet-
ing of the same Club, held on Tuesday, Feb. 12th, Dr. R. W.
Ells read his paper entitled, “Ancient Channels of the Ottawa
River.”

THE TECHNICAL Starr of the Canadian Geological Sur-
vey is being rapidly depleted. Amongst those who have re-
signed are: Dr. A. C. Lawson, Dr. F. D. Adams, and Messrs.
Eugene Coste; E. B. Kenrick, W. P. Ferrier, A. J. Cole, J. B.
Tyrrell and A. P. Low.

Dr. Orro KUNTZE IS UNDERTAKING to supply a series of
typical Monticuliporoidea in thin sections with specimens to
those who may desire to purchase them. Whether these fossils
are Bryozoa or are corals may be left for specialists to decide.
The materials offered by Dr. Kuntze will in either case be of
great value as an aid to the study of monticuliporoids.

Mr. A. P. Low, of the Geological Survey of Canada, it is
understood has accepted a lucrative position in connection with
one of the Nova Scotia trusts. Mr. Low has been regularly em-
ployed on the staff of the Geological Survey of Canada since
1882 and was last year appointed one of the Commissioners for
Canada at the Paris Exposition.

Mr. R. D. Lacog, a well-known geologist and collector
of Carboniferous fossil plants, of Pittston, Pa., died Feb. 5,
IQOI.

Bittincs MemoriAL Portrait. <A fine oil portrait by
Moss, R. C. A., of the late ELKANAH BILLINGS, was recently
presented to the director of the Geological Survey of Canada
and can now be seen adorning the wall of the stairway in the
front hall leading to the museum of the survey, on Sussex
street, Ottawa. The portrait was presented by a ‘committee of
the Ottawa Field-Naturalists’ Club, who acted on behalf of
the subscribers to the Billings’ memorial portrait fund, and
the following inscription accompanies the portrait :

ELKANAH BI Liines, Esq., F. G. S.
Paleontologist from 1856 to 1876.
Presented to the Geological Survey of Canada by a Committee
of the Ottawa Field-Naturalists’ Club, Dec. 11th, 1900, on
behalf of his friends and admirers.

THE

AMERICAN GEOLOGIST.

Vor. XXVIII. APRIL, tgot. No. 4.

THE GRANITIC ROCKS OF GEORGIA AND THEIR
RELATIONSHIPS.*

By THomas LEONARD WATSON, Geol. Surv. of Georgia, Atlanta, Ga.
PLATES XVII-XXIV.

TABLE OF CONTENTS.

PAGE
SOR RES e ENGR ARSIN LC ae ose Cis'Facic Che 5 5p 20558 «seco t= con esick steciceacavaccosee schepoatestvacsss sesdecc «sts 199
(A) THE EVEN-GRAINED NORMAL MASSIVE GRANITES ......cccceceecececeescsneseees 201
Petrography...... ena ssecack castes catebebe tnedatoencced de ssusaleneoeaedevenes sees «ache se cace 201
tae Orlesby-lexineton DIUe-fray, STANCE... ..2<...cecccvcscecsesaeccacacesceet 202
The Elberton-Echol’s Mill light-gray granite.................. cecesececeees 203

The Campbell-Coweta-Meriwether Counties’ medium blue-gray
ASA STIS By 9) aia een Aor ACL GG a SBOE CRU IEE COCR CC au SCRE OACE Aa aLOSRC Ce br arene 204
muck stone Mountain Woht-cray Sanite.......c...5.scecsececcrcoses sdcenscens 206
Pe EUR e OPEL VLG, GRANIT BS sis cesiedasicessadseeds-) ' sefeadsewecees oldvcsoctearecdetesss 208
Ae GMS OUP CIOL racists aye lone tome cise atte vusetask ataceeas toes sas aanines Ss secon: 208
ERA AI ia tewees 022 hassuevserarenace fae sebetacasniccesdescregincsspscaesdopecis sacewedcssac 208
oN RR IRER ENS ANIA AGN ISSICS. 00.5 clone ancedas) shec'coveasnincvedecaenoarereeascausecerendeccctestece 210
PBHceLALnonia belt Of CONTOTECH \BNEISS .c..c.1.. nce scgaces> aanriseedoceboosossce 211
PSU MREtALOL eI NOR CLE GRANITE s. coe csecsssossecinccccaicacsecesctacusenesecacaccocssoerss 213
REPO IG! FELAUCT ONS 7 i iceleaas dee akenveaassccda’s ca donnddadesrsudectbacsseaaaccysacavet vote ss 213
SER IC PER CUTS ey. penned an turcidoisapeascpacesevccsccesreweas esd; canseves 213
COME ACTS HEH OMMCINE ovcen esa svee tosedatacessaseeets ren sacuctesss Osi mewaeeanene 214
PASTE MMI CIUSIONSAYZ 00-5 rctdaj Os sivk sewed otic etianeea ok toate ickeces kus ceneacanen 215
RES ALTING (KES occas cewes deren enh ores cenctuaeary.cndpame tevcun cohen «neehaeost ns 215
MDa CHEMICAL COMPOSILION 25 ic ceaceccuresccreesse Rapends cee usb ude eauanecsiheses 216
Maple On CHEMICAL ANALYSES. icc. secesevesccmseraeed tracted caustewsacet ces coh 216
Molecular ratios, Of the OIE. co, wcdescehecysesseuveaceectutacBerssus 217
ce WEMINM eth) COMIOSUCIONM <2 7cc00cee¥arwaasneavcersenanctorechnacasscoucedes eaneocnaiet 219
MAA CLOCIIMG <1 «ied, catstacs cheb alse seceeiavans scadtaanees cheese p eset AeTatet anit akt Fee 220
PIS CON ACE? can sn de ocselsces syebseciyeccusssGvechstu Apter anees sce tins sumenstey dibeneens 220
RUE CUPUENI TUE, 12.52% eroded push cosncesiiwrs tated tiecded UeedeReppetaue eawee ucutae vebeneavenaun eee es 221
OS VANTEC n sarc aecs a ledvess oo eddie eats. cne ds) Tanaka cobsa duabee MbNTus oth oscil Chidace Sena. oracee 222
SEACH AMC AGULCS osc danisiedscordesosnso)ielate unc anephOctesk cacwashesn idee dietek eae ne 222
Aeeerelarions of the Georgia, STanitic TOCKS. .c..c. secs cnecccdsccacevonsdnvibinascaccaces 223

INTRODUCTION.
In the present paper it is proposed to give a summary of the
results obtained from several years’ careful field and laboratory
study of the granitic rocks, comprised within the limits of the

Piedmont Plateau region of Georgia.

_ * Published by permission of the State Geologist of Georgia. The writer
wishes to acknowledge his indebtedness to PrRoF .JAMES F. KEMP, of Columbia
University, for kindly reading and criticizing this paper in manuscript.

200 The American Geologist. April, 190.

The Piedmont plain in Georgia represents the southern
prolongation of the similar physiographic province in Virginia
and the Carolinas. It is a well dissected low-land plain of holo-
crystalline rocks, crossing the state in a south of west course,
and skirting the southeastern border of the Appalachians with
a gentle seaward slope, and passing on the southeast beneath
the Coastal plain sediments. The plateau has a general average
elevation of 350 to 450 feet above sea level, along the line of
contact with the Coastal plain formations, and an average ele-
vation of 1,000 feet along its northwestern border. A few un-
reduced areas—residuals—of moderate elevation, rise above
the general level of the plain, which, as a rule, represent parts
of harder rock-masses remote from the major streams.

The prevailing rocks forming the Plateau-crystalline-com-
plex are mica-schists, gneisses and massive granites. The
schists more particularly, are cut by numerous well-definet
dikes of basic eruptives, diabases and diorytes,* which vary
from several inches to as many hundred feet in width; and,
in one or two cases, have been traced for some miles in length.,

The mica-schists form a large part of the rock-complex.
They vary somewhat in color; are thinly foliated rocks, and
show considerable variation according to locality in the pro-
portion of mica and quartz and often feldspar. More or less
feldspar is invariably present. The increase in this constituent
may possibly mark in places the transition from schists into cer-
tain gneisses of granitic composition. This can in nowise ap-
ply, however, to the gneisses thus far studied in this area, since,
in many instances, sharp contacts are plainly marked between
the two rocks. The basic dike rocks vary from fine to coarse
granular in texture; they are occasionally porphyritic and fre-
quently banded in structure, and gray to black in color. The
usual normal rock-types are present, which, as a rule, present
no unusual features in mineral composition. The dikes are
limited for the most part, to the enclosing schists and are rare-
ly actually seen cutting the granitoid rocks. The granitic rocks
are traceable across the entire width of the state, and are ac-
cordingly of wide distribution throughout the Piedmont area;

* Other basic rocks usually laminated or thinly schistose in structure and
somewhat porphyritic in places, simulating dikes and grouped for the most
part at present, as amphibolytes have not been sufficiently studied to warrant
definite statements.

THE AMERICAN GEOLOGIST, VOL. XXVII. , PLATE XVII.

3 = =

PLratE XVII. Ficure 1. PHOTOMICROGRAPH OF HORNBLENDE SCHIST
(AMPHIBOLITE) CONTAINING MUCH EPIDOTE. FOUR MILES SOUTHEAST
OF LAWRENCEVILLE, GEORGIA. CROSSED NICOLS X74.

FIGURE 2. PHOTOMICROGRAPH OF HORNBLENDE GNEISS (AMPHIBOLITE).
MERIWETHER COUNTY, GEORGIA. X74.

Piedmont Plateau of Georgia—Watson. 201.

and are associated with similar rocks continuously into South
Carolina.

In the western section of the plain, near the Alabama line,
somewhat extensive belts of very dark-colored, thinly banded
hornblende gneisses or amphibolytes are met. [Plate XVII,
figures I and 2.]_ They are strongly contrasted with the gran-
itic gneisses with which they are intimately associated. In thin
sections, hornblende of a greenish-brown and blue color makes
up half the rock or more. Plagioclase is the prevailing feld-
spar, but orthoclase and quartz in variable amounts always ac-
company it. Epidote is a frequent characteristic accessory.

On general textural and structural grounds, the granitoid
rocks are grouped and separately treated under three general
headings: (a) The even-grained, normal, massive granites,
(b) porphyritic granites, and (c) granite-gneisses.* The
relationships of the three phasal aspects of the granite rocks
are established in the succeeding paragraphs.

(A) THE EVEN-GRAINED, NORMAL, MASSIVE GRANITES.

Granites of superior quality and variety, well-suited for
general building and monumental work, have long been known
in Georgia. Their extent, distribution, physical, mineral and
chemical characters, however, are almost entirely unknown,
since no systematic geological work has been undertaken. Un-
til quite recently, the famous Stone mountain light-gray bio-
tite-bearing muscovite granite was the only type of Georgia
granite known outside the state. Within the past few years,
however, several areas yielding a high grade monumental gran-
ite have come somewhat prominently into favor in some sec-
tions of the United States.

PETROGRAPHY.

With two exceptions, all the granites are biotite granites.
Muscovite is prevailingly present in variable amounts, and
very prominent as an accessory in some places; while horn-
blende fails entirely. They are described under the following
types: The Oglesby-Lexington blue-gray; the Elberton-Ech-
ol’s Mill light-gray; the Campbell-Coweta-Meriwether coun-
ties’ medium blue-gray ; the Stone mountain light-gray,

* The term granite-gneiss is used in this paper to denote gneisses derived

from massive granites by met2morphism, and therefore igneous in origin, as
contrasted with those gneisses of known sedimentary origin.

202 The American Geologist. April, 200L

Numerous smaller areas are widely distributed over the
Piedmont region, but, in the cases studied, they naturally fall
into one or the other of the types mentioned above, separate de-
scriptions of which are unnecessary and beyond the scope of
the present paper.

THE Ocresspy-LExINGTON BLuE-GrAy GRANITE. The
Oglesby-Lexington belt of dark-blue granite is continuous for
thirty miles in a northeast-southwest course, with an average
of four to six miles in width. Practically no variation in tex-
ture is noted within these limits, but appreciable color variation
is apparent in places, according to the quantitative variation in
the biotite constituent.

This variety consists of anhedra of an average size, 0.5-1.5
millimeters. [Plate XVIII, figure 1.] The texture is hypidio-
morphic granular. Simple Carlsbad twins among some of the
feldspars are readily recognizable in many of the hand speci-
mens. The principal minerals are quartz, orthoclase, micro-
cline, plagioclase near oligoclase, biotite, some muscovite, a
little included apatite and zircon, and occasional grains of mag-
netite and pyrite. Secondary chlorite, epidote, muscovite and
‘kaolin are present to some extent. In addition, as an intersti-
tial constituent, quartz is frequently present in drop-like in-
clusions in the larger feldspar individuals; and, at times, is in-
tergrown with a part of the feldspar in the form of ovals or

.rounded discs of micropegmatitic intergrowths. The period
of growth of the quartz and feldspar was in part simultaneous.
Urthoclase is the predominating feldspar present, and frequeént-
ly exhibits microperthitic intergrowths with a second feldspar,
probably albite. Microcline varies in quantity, but at times
may equal the orthoclase. The habit of simple Carlsbad twins
is common to the two potash feldspar varieties. The plagio-
clase is always inferior in amount to the potash feldspars, and,
as a rule, gives low extinction angles in basal sections. The
percentage of lime in the analyses given below with the micro-
scopic evidence indicates oligoclase as the triclinic feldspar
present. The biotite is regularly distributed through the rock
in irregular drawn-out single shreds and foils, deep brown in
color and strongly pleochroic. It is intimately associated with
foils of muscovite and is partially altered to chlorite. The re-
maining accessories present no note-worthy features.

THE AMERICAN GEOLOGIST, VOL. XXVII. PEATE 26 VII:

Pirate XVIII. Figure 1. PHOTOMICROGRAPH OF THE OGLESBY DARK-
BLUE GRANITE. ONE MILE SOUTH OF OGLESBY, ELBERT COUNTY,
GEORGIA. CROSSED NICOLS —x74.

y ene
PLATE XVIII. \FicurE 2. PHOTOMICROGRAPH OF THE EcHoL’s MILL
LIGHT-GRAY GRANITE. ELEVEN MILES NORTHEAST OF LEXINGTON,

OGLETHORPE COUNTY, GEORGIA. CROSSED NICOLS x74.

Ve i
4} ‘ }
Tutt “ea
Me oad
wet, Ae

“y

Piedmont Plateau of Georgia.—W atson. 203.

CHEMICAL ANALYSES OF THE OGLESBY-LEXINGTON DARK BLUE GRANITE.

I II Il IV Vv VI Vil Vill

SiO2 70.38 70.30 70.18 70.03 69.74 69.64 69.53 69.36
AlzOs* 1647 16:17 17.30 15.62 .16.72 17.21 1646 17.23
Fe2Ost 1.17 aa) 1.20 1.31 1.45 1.32 1.15 1.43
CaO Ae 2.61 2.03 2.45 1.93 2.14 2.10 2.14:
MgO 0.31 0.31 0.64 0.52 0.36 0.66 0.85 0.59
K20 5.62 5 : : :

Na20 4.98 4.72 436 4.82 4.84 4.53 5.00 5.17
IRgni 0,31 OCs, Osos O70 O47 0,35 0.91 0.33

eee

Total 100.96 100.81 100.83 100.94 100.84 100.80 100.91 100.82

I. Biotite granite from Swift & Etheridge quarry, 4 miles west of
Elberton, Georgia.
Il. Biotite granite from Diamond Blue Granite Co.’s quarry, near
Hutchins, Oglethorpe Co., Ga.
III. Biotite granite from Brown & Deadwyler quarry, Madison coun-
ty, Georgia.
IV. Biotite granite from Lexington Biue Granite Co.’s Quarry, Lex-
ington, Georgia.
V. Biotite granite from Coggin’s Granite Co.’s quarry, near Ogles-
by, Elbert county, Georgia.

VI. Biotite granite from Coggin’s Granite Co.’s quarry No. 2, near
Oglesby, Georgia.
VII. Biotite granite from outcrops near Hutchins, Oglethorpe county,
Georgia.
VIII. Biotite granite from the Child’s quarry, near Oglesby, Georgia.
THE Evperton-Ecuor’s Mitt Jacut-Gray GRANITE:

This type is represented by a belt of approximately the same
dimensions and general direction as,,the Oglesby-Lexington
blue-gray granite, which it limits immediately on the southeast.
The two areas are contiguous, and while well differentiated as
to color, and in a less degree texture, in their extreme portions
they undoubtedly form parts of the same general area, as the
gradation is well shown near Elberton and Carlton.

~The Elberton-Echol’s Mill light-gray type does not differ
essentially in mineralogy from the Oglesby-Lexington dark
blue granite, although they are strongly contrasted in the hand
specimens. ‘The difference is essentially one of color, with the
biotite distributed at greater intervals and in somewhat stouter
aggregated shreds in the light-gray granite. As a rule, the
light-gray type is slightly more coarsely crystalline than the
dark-blue variety. The same minerals are present in nearly
the same proportions and show the same characteristics in the
two types. Quartz, orthoclase, microcline, plagioclase, biotite,

*Contains traces of P2Os, TiOz and ZrOzg when present.
,Alliron estimated as Fe203.

204 The American Geologist. April, “2901,

a little muscovite, apatite and zircon are all present. [Plate
XVIII, figure 2.]

CHEMICAL ANALYSES OF THE ELBERTON-ECHOL’s MILL LIGHT-GRAY

GRANITE.
Ts if Oe Ill.
SiOe 69.45 69.25 68.81
AleOzg 15.93 16.04 17.67
Fe203* Wasp b Be 1.13
CaO ALOT 1.89 isk
MgO 0.55 0.31 050
Ke0 5.16 4.94 3.90
Naz2O 4.33 4.52 4.97
Igni 0.50 0.43 0.30
Total 99.14. 99.10 99.45

I. Biotite granite from Swift and Wilcox quarry, 1 mile south of
Elberton, Georgia.
II. Biotite granite from Tate and Oliver quarry in the limits of
Elberton, Georgia.
Ill. Biotite granite from Echol’s Mill, 12 miles northeast from Lexing-
ton, Georgia.

THE CAMPBELL-COWETA-MERIWETHER COUNTIES’ MEDIUM
BLuE-GrAy GRANITE: In addition to the normal massive gran-
ites, coarsely crystalline porphyritic granites and granitic
gneisses of essentially the same mineral and chemical composi-
tion, are found in intimate association over parts of Campbell,
Coweta and Meriwethé tounties.

The even-granular 'nfdssive type of granite is of two varie-
ties. One, the medium gray, is an average fine-textured crys-
talline rock consisting of anhedra of an average size, 0.5-1.5
millimetres. [Plate XIX, figures 1 and 2.] The other, a dark-
blue-gray, occurs in the southwest section of Meriwether coun-
ty. [Plate XX, figure 1.] It is more coarsely crystalline and
darker in color and contains a larger proportion of biotite, than
the medium gray type.

The medium gray type traverses Campbell, Coweta and
Meriwether counties, in a nearly north-south course, with
quarries opened near the respective county seats, Fairburn,
Newnan and Greenville. The variation in color and texture,
in general, is very slight. The northern part of the granite-
mass, in the vicinity of Fairburn, is somewhat lighter in color,
with the middle and southern parts near Newnan and Green-
ville, correspondingly darker. This type is closely similar in
mineral and chemical composition to the Oglesby-Lexington

* All iron estimated as Fe203;.

THE AMERICAN GEOLOGIST, VOL. X XVII. PLATE XIX.

PLate XIX. Ficure 1. PHOTOMICROGRAPH OF THE CAMPBELL-COWETA-
MERIWETHER COUNTIES’ MEDIUM BLUE-GRAY GRANITE. TWO MILES
NORTH OF FAIRBURN, CAMPBELL COUNTY, GEORGIA. CROSSED NICOLS
x74.

Pirate XIX. Ficure 2. PHOTOMICROGRAPH OF THE GREENVILLE MED-

IUM BLUE-GRAY GRANITE. GREENVILLE GRANITE COMPANY’S QUARRY,
GREENVILLE, MERIWETHER COUNTY, GEORGIA. (CROSSED NICOLS X74.

THE AMERICAN GEOLOGIST, VOL. X XVII. PLATE XX.

Se, *
PLATE XX. FIGURE I. PHOTOMICROGRAPH OF DARK-BLUE-GRAY GRAN-
ITE NEAR ODESSADALE, MERIWETHER COUNTY, GEORGIA. CROSSED

NICOLS X74.

PLATE XX. FicureE 2 PHOTOMICROGRAPH OF THE STONE MOUNTAIN
LIGHT-GRAY GRANITE. STONE MOUNTAIN, DEKALB couNty, GEORGIA.
CROSSED NICOLS x74.

= .

PD & “
:

Piedmont Plateau of Georgia.—Watson. 205

blue-gray, and the Elberton-Echol’s Mill light-gray types, and
is intermediate in color and texture between the two latter va-
rieties. The component minerals are quartz, orthoclase, mi-
crocline, plagioclase near oligoclase, biotite, a little muscovite,
apatite and zircon. Some secondary epidote and chlorite from
the alteration of feldspar and biotite are usually present. Sev-
eral small garnets have been noted in one or two places in the
northern part of the belt. The orthoclase is microperthitic in
structure and is the predominating feldspar. Microcline
nearly fails in places and is very abundant in others. Plagio-
clase is of the usual kind noted above. Rounded disks of micro-
pegmatitic intergrowths of quartz and feldspar are common.
Biotite is present in variable amounts intimately associated
with muscovite. Muscovite is always subordinate to biotite
in amount. ‘The biotite is deep brown in color with strong ab-
sorption and variously altered to chlorite. Epidote, in the
form of irregular grains and idiomorphic crystals, is somewhat
abundant in thin sections of the Cole quarry granite near
Newnan. The increased percentage of lime in the analysis
of this rock corroborates the microscopic evidence (see analy-
sis I.)

CHEMICAL ANALYSES OF THE CoweEeTa County MeEpium BLUE-GRAY

GRANITE.
L. II. IIL.
SiO» 69.08 69.07 68.79
Al203* 17.67 16.56 16.48
Fe2Oat sl 1.37 0.98
CaO 3.27 1.83 1.76
MgO 0.64 0.76 1.30
K20 3.29 5.02 5.85
Na2O 4.56 4.65 4.74
Igni 0.56 0.92 0.38
Total 100.48 100.18 100.28

I. Biotite granite from the Cole quarry, near Newnan, Georgia.
II. Biotite granite from the Overby quarry, 10 miles northeast from
Newnan, Georgia.
IlI. Biotite granite from the Hill quarry, 3% miles southeast from
Newnan, Georgia.

The dark gray variety is more coarsely crystalline than the

preceding and contains more biotite and perhaps more plagio-
clase as a rule, with slightly less quartz. The specific gravity

* Contains traces of P20s, ZrO2 and TiOz when present,
; Alliron estimated as Fe2Os3.

206 The American Geologist. April, "100s:

and chemical analysis given in table A, corroborate the above
inferences. The component minerals are essentially the same,
but in slightly, varying proportions, as for the preceding types.

THE Stone Mountain Licut Gray GRANITE: The Stone
mountain light gray variety is strongly contrasted with all
other types of granite in the state. In mineralogy it differs
only in the reversed proportion of biotite to muscovite, and is

a biotite-bearing muscovite granite. Biotite is a constant ac- -

companiment, but is greatly subordinated to muscovite in
quantity. This type is uniformly light gray in color over the
entire area, but shows some variation in texture, in places. It
is intermediate in texture between the other types of normal
granite on the one hand, and the coarsely crystalline granite

matrix of the prophyritic granites on the other. As a rule, the-

Stone mountairi type consists of anhedra ranging in size from
1.5-2.5 millimetres. [Plate XX, figure 2.] The potash feld-
spars predominate with orthoclase usually in’excess of micro-
cline. The orthoclase is commonly interwoven with a second
feldspar in microperthitic structures. Microcline is subject to
considerable variation in amount, at times, equaling that of
the orthoclase in places, and sinking to a minimum in others.
Plagioclase is only subordinate to the postash feldspars in
amount, and occurs as stout laths with the characteristic poly-

synthetic twinning, lamellz affording as a rule low extinction ~
angles on the base. Quartz, in addition as irregular interstitiat

grains, is common in drop-like inclusions in the feldspars.
Muscovite occurs either as individual flakes or aggregates with
strong double refraction and often a faint yellowish tinge.
The ray vibrating parallel to the cleavage shows appreciable
absorption in many flakes. Biotite, as single foils with the
usual pronounced color and absorption, is associated with the
muscovite. Accessory apatite and zircon, and secondary chlo-
rite, complete the list of microscopic minerals present. (See
analysis I, table A.)
Several minerals not met in thin sections of the Stone
mountain granite are frequent microscopic accompaniments in
the rock. The most abundant one of these is black tourma-
line. This mineral is present, in every block of stone quar-
ried, in the shape of aggregated small prismatic crystals usu-
ally without terminal faces, embedded in a perfectly white ir-

Piedmont Plateau of Georgia.—Watson. 207

regular oval-shaped area of quartz and feldspar, from which
the two micas, muscovite and biotite, have been excluded. As
a rule, the white areas containing the tourmaline bunches are
only a fraction of one inch to several inches in diameter, though
larger ones are by no means exceptional. Small crystals of
red garnet are not uncommon. The joint planes exposed in
several quarries on the north side of the ridge are coated with
a sulphur-yellow incrustation, which, upon chemical investiga-
tion, proved to be a mixture of uranophane and hyalite, with
the former in excess.

Approximately 12 miles southwest from Stone mountain
in the same county, is a second exposure of a biotite-bear-
ing muscovite granite, light gray in color and finely crystalline
in texture. The rock has been used to some extent as a mon-
umental stone. It consists of the same materials in the same
proportions as the Stone mountain granite. Micropegmatitic
intergrowths of quartz and feldspar are common. The pris-
matic inclusions of apatite in the quartz are frequently bent and
broken, and, in some cases, the parts have slipped past each
other.

Some effects of strain are frequent in all the above types
of granite, indicating that they have suffered from partial
dynamic metamorphism. The microscopic evidence strength-
ening this conclusion is undulatory extinction in the quartz;
fracture lines crossing the quartz and sometimes the larger
feldspar anhedra; and somewhat increased microcline in
- places, manifesting some evidence of a strained condition. In
Meriwether county, and several of the nearby counties, areas
of rather pronounced foliated granites of the same mineral and
chemical composition, resembling in other respects the massive
phases, are found. The gradation, if such exists, between the
massive and foliated granites could not be satisfactorily traced
in the field, in this area, but the laboratory evidence strongly
favors such. If this be true, the traceable gradations in the
field are rendered impossible on account of few exposures and
the very heavy covering of residual decay. In thin sections of
the foliated rocks, the evidence of pressure metamorphism is
increased in some peripheral shattering of the larger quartz
and feldspar individuals. Pressure metamorphism is further
made evident in the Stone mountain type in a slight pseudo-
foliation.

208 The American Geologist. Apert, 1a"

(B) THE PORPHYRITIC GRANITES.

The porphyritic facies of the Georgia granites are else-
were described and discussed at some length by the writer.”
The individual areas are described in detail and their relations
to the normal granite facies stated. For the purposes of the
present paper, it is only necessary to note their distribution
and briefly describe them as a whole, detailing their chief char-
acters so far as they bear on the present problem.

More than a half-dozen well-defined separate areas of
coarsely crystalline porphyritic granites are noted within the
limits of the Piedmont Plain of Georgia. In every case, they
are associated with an even-granular facies of the same rock,
having the same mineral and chemical composition. The por-
phyritic areas have been designated as follows: The Camp-
bell-Coweta-Fayette counties’ area; the Pike county area; the
Fulton county area; the Brinkley place-Holder’s Mill area; the
Sparta area; the Milledgeville area; the Greene county area;
the Columbia county area.

GENERAL DEscRIPTION: Certain general features are com-
mon to all the porphyritic areas, although the rocks are strong-
ly contrasted in many. With one exception, they are all mas-
sive in structure, without, as a rule, trace of the primary or
secondary foliated structure. The exception is in the Brink-
ley Place-Holder’s Mill area, where the rock has a pronounced
schistose structure, clearly due to pressure metamorphism.
The porphyritic granites are prevailingly coarse-grained and
light to dark gray in color, according to the amount of biotite
present.

PETROGRAPHY.

The groundmass or matrix is a typical coarse biotite granite
without the foliated structure. It consists of anhedra meas-
uring 3 to 8 millimetres in size. [Plate XXI, figures 1 and 2.]
The principal minerals are quartz, orthoclase, microcline, plagi-
oclase, biotite, a little muscovite, apatite and zircon. Some
chlorite and epidote derived from the alteration of the feldspar
and biotite occur. Quartz is abundant and the feldspars have
the same general characters as in the even-granular types of

* Journal of Geology, 1901, vol. ix, February-March number. A Prelimi-
nary Report on the Granites and Gneisses of Georgia, Geol. Sur. of Ga., in press.

THE AMERICAN GEOLOGIST, VOL. XXVIII, PLATE XXI,

PLATE XXI. Ficure I. PHOTOMICROGRAPH OF PORPHYRITIC GRANITE
TEN MILES SOUTH OF GREENESBORO, GREENE COUNTY, GEORGIA. CROSSED
NICOLS X74.

PLATE XXII. FicureE 2. PHOTOMICROGRAPH OF PORPHYRITIC GRANITE
NEAR CoweTA STATION, CowETA COUNTY, GEORGIA. CROSSED NICOLS
7A.

Piedmont Plateau of Georgia.—Watson. 209

granite described above. Microcline is possibly subject to
more variation than in the normal granites, and plagioclase
is, as a rule, slightly increased. The feldspars are usually
white opaque in color, with greenish-white and pink tints not
uncommon. The interstitial feldspar is transitional into the
phenocrysts in several areas. The quartz frequently crystal-
lized simultaneously with the feldspars, resulting in the forma-
tion of ovals of micropegmatitic structures, common in the thin
_ sections from all the areas. Biotite is variable in amount but
occurs in stout plates, deep brown in color and strongly pleo-
chroic. Apatite is very abundant in the form of stout pris-
matic inclusions in some slides and almost fails in others.

The phenocrysts are usually opaque and white in color
with pink tints common. They vary from 10-50 millimetres
long and 5-10 millimetres across; and vary from allotriomor-
phic to idiomorphic in crystal outline. The idiomorphic type
prevails, however; flat, tabular parallel to the clinopinacoid
(O10), with (oor) and (101) cleavages well developed. They
display the usual habit of simple Carlsbad twins. Only the
potash varieties, orthoclase and microcline, are porphyritically
developed, and, as a rule, are intergrown with a second feld-
spar in microperthitic fashion. They invariably contain in-
clusions of all the groundmass minerals, which with other evi-
dence, indicates simultaneous growth with the interstitial com-
ponents. The inclusions of biotite plates are always macro-
scopic in size and, in many cases, the included mica is equally
large as the same interstitial mineral. The IN PLACE as against
INTRATELLURIC origin for the phenocrysts has been elsewhere
pointed out.

Analyses of carefully selected fragments of the feldspar phenocrysts
from two of the areas yielded the following results:

if int
SiOz 64,64 64.40
AleOg 19.64 18.97
Fe203 0.37 0.37
CaO 0.67 0.59
MgO ti: 19)
K20 10.00 11.40
Naz2O 3.06 3.60
Ignition 0.22 0.19
Total 98.60 99.52
Sp. Gr. 2.60 2.55 (Thoulét solution.)

I. Feldspar phenocrysts from Columbia Co. porphyritic granite mass.
1 ae “ec fe Coweta ae te fe ae

210 The American Geologist. April, 190%

(See analyses IX, X, XI, XII, XIII, XIV, and XV of
Table A.)

Gradation from the porphyritic facies, peripherally, into a
medium coarse-textured non-porphyritic granite facies of the
same mineral and chemical composition is traceable in some of
the areas. The lack of field evidence favoring gradation in
the other areas is probably due to absence of exposures. As a
rule, the rocks in the Georgia area, as well as in the southern
states in general, are covered by a heavy mantle of residual
decay, and exposures of fresh rock are limited and by no means
continuous.

Extensive areas of gneiss of granitic composition abound
in the Piedmont Plain, and in abundance, becomes one of the
most, if not the most important rock in the plateau-complex.
The gneisses vary from medium to coarsely crystalline rocks
with a pronounced banded or schistose structure. The planes
of schistosity vary from moderately irregular to highly contort-
ed lines with the banding exceedingly irregular; from very
thick to very thin layers. They are closely related genetically
to the massive granites from which they differ only in the
banded structure, secondarily imparted through dynamo-
metamorphism. The two types—gneisses and massive gran-
ites—are essentially alike in mineral and chemical composition.
The minerals found in one are invariably present in the other.
Furthermore, the minerals most abundant in the one also pre-
dominate in the other. Like the massive granites, the acid
gneisses are all biotite gneisses. Muscovite is an invariable
associate but is subordinated in every case to the biotite in
quantity ; and hornblende is never present. The acid gneisses
studied are believed for these and other reasons stated later,
to be metamorphosed irruptive granites and are therefore des-
ignated granite-gneisses.

Separate descriptions of the individual areas can not be de-
tailed here, but instead, several of the larger and representative
ones will be briefly described as illustrating their composition.

* There may be and probably are gneisses of sedimentary origin in the
Plateau-crystalline-complex, but the areas of gneiss so far studied afford no
a of such origin. The discussion is entirely limited to those areas
studied.

THE AMERICAN GEOLOGIST, VoL. X XVII, PLATE SEE

PLateE XXII. Ficure1. PHoToMICROGRAPH OF THE LITHONIA CONTORT-
ED BIOTITE GRANITE-GNEISS NEAR LITHONIA, DEKALB COUNTY, GEORGIA.
CROSSED NICOLS x74.

Om,

a
2. PHOTOMICROGRAPH OF A FINE-GRAINED DARK-
BLUE BIOTITE GRANITE FROM A DIKE FORTY FEET WIDE, CUTTING THE
PORPHYRITIC ,GRANITE-GNEISS, NEAR CAMAK, WARREN COUNTY
GEORGIA. CROSSED NICOLS x74.

PLATE XXII. Ficure 2

Piedmont Plateau of Georgia.—lWatson. 2It

THE LITHONIA BELT OF CONTORTED GNEISS: The Lithonia
belt of gneiss is continuous over a large part of three contig-
uous counties, and lies immediately adjacent on its north and
west sides to the famous Stone mountain light-gray granite
area. The belt takes its name from the town of Lithonia, lo-
cated near the centre of the quarrying industry. The rock has
been quarried very extensively as blocks and curbing for street
paving, and has been shipped to the principal cities in the
south and middle west. ‘

It is an irregularly banded, highly contorted, biotite gran-
ite-gneiss, medium light-gray in color, and composed of anhe-
dra ranging in size from 0.5-2.5 millimetres. [Plate XXII.
figure 1.] The principal minerals are quartz, orthoclase, micro-
cline, plagioclase, biotite, a little muscovite, apatite, zircon and
magnetite. Some secondary chlorite, epidote, kaolin and mus-
covite occur. Idiomorphic crystals of red garnet are very com-
mon in some of the quarries. The garnets form in some cases
distinct lenses and layers alternating with bands of the prin-
cipal minerals, and are also scattered as single crystals through
the rock. Small areas of black tourmaline are distributed in a
similar manner through the granite-gneiss to that of the Stone
mountain granite, with the exception that the areas are by no
means so frequent in the former rock as in the Stone moun-
tain type.

Orthoclase is the predominating feldspar and in part is
microperthitic in structure. Microcline is subject to much
variation with a general average increase, somewhat larger for
the gneisses than for the granites. The increase in this con-
stituent in the foliated granitic rocks over the massive types
can probably be accounted for on the basis of pressure meta-
morphism, as numerous pieces of the mineral show some indi-
cations of a possible induced structure, such as might result
from excessive strain. A large percentage of this constituent
however, is undoubtedly primary in origin, while the remain-
der is somewhat doubtful. Plagioclase is also variable in
amount and is present in the form of stout laths with charac-
teristic polysynthetic twinning, affording small extinction
angles in basal sections. Biotite, as deep brown-colored and
strongly pleochroic foils, is drawn out along roughly parallel
lines. It is associated with smaller amounts of muscovite, and,

212 The American Geologist. April, 1901.
as a rule, carries microscopic inclusions. Quartz, with occas-
ional grains of feldspar, are common in drop-like inclusions
in the larger feldspar individuals. Micropegmatitic inter-
growths of quartz and feldspar do not fail entirely in thin sec-
tions of the granite-gneiss, but are less frequently met than in
the massive granites. .

A second area of similar highly contorted gneiss begins
in Troup county in middle southwest Georgia near the Ala-
bama line, and crosses Meriwether county in an east-west
course. Hand specimens of the rock from the two areas are
indistinguishable and are identical in mineral and chemical
composition.

The other areas of gneiss are strongly contrasted, and vary
in degree and regularity of the foliated structure, and in color
and texture. The relationships, while not entirely clear in the
field, possibly suggest that several of the areas may be the
transitional foliated phases of the massive granites, but so far
as the writer’s observations extend, the conditions strongly
point to no gradation of the typical gneisses into the equivalent
massive rocks. They are all, however, biotite granites with
the same minerals present in nearly similar proportions. This
fact is further corroborated in the table of analyses where the
rocks are seen to be nearly identical in composition. (See an-
alyses XVI, XVII, XVIII, XIX, XX, XXI, XXII, and XXIII
Table A.)

That the schistose or foliated structure is entirely secondary,
resulting from pressure metamorphism, and not primary, is
plainly manifested in the thin sections of these rocks. The
quartz and feldspar grains are invariably rimmed by crushed
zones of the two minerals; the quartz extinguishes irregularly ;
and numerous lines of fracture are common to both quartz
and feldspar. The Lithonia area of contorted gneiss, how-
ever, affords but slight if any evidence of periphera! shattering,
which likely indicates recrystallization of the minerals through
profound metamorphism.

eas

“Cava LVAM ATHAAC AWV LSTHOS DNISOTONaA ANV ALINVUD AHL H1Log
“VTDMOME) ‘VINVILY YVAN JSIHOS VOIN ONILIND AMI ALINVUD ALILOIA GANIVUD-ANIYA “ATX X FLVId

“AIXX ALW Td TIAXX “IOA ‘LSINOTOAUH NYOMWANY AHL

Piedmont Plateau of Georgia.—Watson. 213

CHEMICAL ANALYSES OF THE LITHONIA CONTORTED GRANITE-GNEISS,
DEKALB CounNTY.

I. i Ill.

SiOz 76.00 75.16 72.96
AlzOzg “13.11 13.74 14.70
Fe203* 0.92 0.91 1.28
CaO 1.06 0.91 1.28
MgO 0.27 0.17 0.07
K20 4.69 . 5.05 4.73
NasO 3,88 3.76 4.18
Ig=.. 0.31 0.32 0.23
Total 100.24 100.02 99.43

I. Biotite granite-gneiss from the Crossley quarry, near Lithonia,

Georgia.
II. Biotite granite-gneiss from the Arabia Mountain quarries 3 miles
from Lithonia, Georgia.
III, Biotite granite-gneiss from the Southern Granite Co.’s quarry,
near Lithonia, Georgia.

Intrusive nature of the granites.

The evidence of the igneous origin of the Georgia granites
is essentially the same as for similar irruptive acid masses
studied elsewhere. The evidence is from, (1) field rela-
tions ; (2) chemical composition ; and (3) mineral composition,

I. Field relations.

STRATIGRAPHIC FEATURES: The exposures of the gran-
ites in the field point to rounded or elliptical forms common to
intruded granite masses. The two granite facies—porphyritic
and non-porphyritic—may be considered as one, since in many
of the granite areas the porphyritic structure grades peripher-
ally, into a non-porphyritic granite facies of the same mineral
and chemical composition, and are from necessity of the same
origin. In the case of the foliated phases of the granites, the
schistosity is not co-incident with that of the surrounding
schist, but cuts across the foliation of the latter.

Near many of the larger granite-masses well-defined gran-
ite dikes, slightly different in texture from, but of the same
mineral and chemical composition as the mass, occur, which
would commonly be regarded as apophyses in case the rock is
regarded as eruptive. [Plate XXIV.] These dikes or
apophyses project outward from the main rock-mass and cut
abruptly into the adjacent rocks. A chemical analysis of spec-

* Alliron estimated as Fe20O3.

214 The American Geologist. April, 100%.

imens collected from a 40-foot dike cutting the porphyritic
granite-gneiss near Camak on the Brinklley place, yielded the
writer the following results:

SiOe2 Ae Dee Necubs ‘sShevduh GuseeVgletensielonedve'thdecen cave séeces 68.76
yA) ON 0 Raa a ana nce A ee na de Remaee eB Picea aia 16.80
Fea Obs: Sines ences tee reco tech ctae conents PARE, ese 0.99
CADS eta tere ee eae eee eae eee 2.72
Myo er se ieun cect etecectnconn sancccec aera s tee cent eee 1.00
Na2O Cavan cocccccenvlevesn cceteveccscecesuesscescveccccocssec’ 4.82
ea O i dics deis score cae dase Serer news beakers Ldcaseseetsace 3.70
Tipepn rrr eieastece<cacsack Sec ershcsce ste crcancneeeccssesnese 0.29

ROTA es cen ertanven tacoma oee eeeet ccc stees 99.08

A comparison of this analysis with analyses of the normal
even-granular granites reveals practically no difference. The
acidity, as will be observed, is essentially the same.

In addition to the quartz, feldspar varieties and biotite, thin
sections showed inclusions of apatite and zircon, and drop-like
inclusions of quartz and feldspar grains in the larger feldspar
individuals, along with rounded disks of micropegmatitic inter-
growths of quartz and feldspar. [Plate XXII, figure 2.]

CONTACT PHENOMENA: In all cases where contacts of the
granitic rocks and schists were visible, they were, in the opin-
ion of the writer, plainly eruptive. . Although many contacts
have been examined, they are not so numerous as might be ex-
pected, on account of the deep covering of residual decay.
The line of contact is usually sharp and somewhat irregular in
the localities where best exposed. No considerable contact
metamorphism of the surrounding rocks was visible, however,
in any exposure. Since the surrounding rocks are equally
completely crystalline, as a result of profound metamorphism,
any considerable alteration would hardly be expected. Many
granite intrusions into crystalline rocks showing little or no
contact metamorphism have been observed in different locali-
ties by various writers. None of the commonly associated
minerals of contact phenomena are present in the sections exam-
ined. In some areas, garnets, and tourmaline are very com-
mon, but their occurrence is as frequent away from the contact
as near it, and cannot be considered a result of contact met-
amorphic action between the rocks. In no case has any definite
gradation from the acid rocks into the schists been observed in
the field, but the two appear strongly differentiated.

ee “Go Mere ee my ay SD nat a ae hk ak a Z : ‘ .

- i
aS
:
.
mA)
;
. e
‘
; *
; { \ k
ed , re ae J
ia :
PLAS a a°<¢
Sod ey o a 3 : ie
ae. i ae
af, x ~< i iY Aa
4,7 ty fet a “s p
Su eee : ' m :
“¥ a, - *

‘GAUANASANd TIAM FAV “SOOM HSAIAT AHL AO
SANVId ALISOLSIHOS AHL HOIHM NI AVTIO IVAGISAN SNONIONWWA V OL GAYAHLVAM AAV SLSTHOS

OSNISOTONI JH] ‘VIONOdS) ‘VINVILV YVAN LSIHOS VOIW ONILIND SAMIC DILILVWOAG

TIIXX v1

TIIXX ALVIg TIAXX “IOA ‘LSID010N NYOIMUANY AU

Piedmont Plateau of Georgia —Watson. 215

Basic INCLUSIONS: Another form of evidence strongly
favoring the irruptive nature of the granitic rocks is that of
inclusions darker in color and considerably more basic in char-
acter than the parent rock, met in many of the masses. It has
not been possible to distinguish in every instance between in-
clusions of the inclosing rock and that of darker material—
schlieren—basic segregations of the granite magma. In the
majority of cases, the darker areas plainly represent basic seg-
regations, which form so common a feature of slowly solidify-
ing granite magmas. They are especially abundant in many
of the quarries; are darker in color than the parent granite and
consist chiefly of biotite with subordinate quartz, orthoclase,
plagioclase and apatite, with no evidence of foliation. They are
rounded and irregular in outline and, in case of the gneisses,
form lenticular patches and bands in extreme cases. Asa rule,
they are finer-grained in texture than the inclosing rock, but in
some cases they are coarser crystalline. Inclusions of this
character are regarded by many writers* as strong evidence of
the eruptive origin of the rocks in which they are found.

PecMATITiIc Dixes: Closely associated pegmatitic dikes
of varying width and granitic composition are numerous
throughout the Plateau-crystalline complex, and are unques-
tionably genetically connected, in many cases, with the granite-
masses. They vary from those of granitic composition to
pure quartz. Under this heading two kinds of material are
met. Some are true pegmatitic intrusions, while others are
true veins of segregation. Both are common to the porphyritic
and non-porphyritic granite facies and to the gneisses, and are
equally characteristic of each. They are characterized by the
usual coarse-grained structure and consist almost exclusively
of lustrous, cleavable pink and white-tinted feldspar with some
quartz, and a much smaller proportion of biotite, and occasional
muscovite. [Plate XXITI.] In many cases they are very exten-
sive and deep-seated, while in others they are very limited in
extent and are entirely surrounded by the granitic rock. They
are very irregular in outline, conforming to no uniform orien-
tation, but cut the rock in numerous directions and at various

* ROSENBUSCH, MASSIGE GESTEINE, p. 62,

WILLIAMS, G. H., 15th Annual Report, U. S. G. S., p. 662.
Kemp, J. F., Bull. Geol. Soc. Amer., 1899, vol. x, pp. 371-372.
WESTGATE, L. G., Journ. of Geol., 1899, vol. vii, p. 643.

216 The American Geologist. April, 1901.

angles. Thin sections of several of these masses show micro-
cline, orthoclase and plagioclase feldspars, with occasional
microperthitic structures, a few shreds of biotite and some
quartz. Hand specimens of others showed nearly equal pro-
portions of feldspar and quartz with occasional biotite plates.

2. CHEMICAL COMPOSITION.

The following analyses give a good idea of the range in
composition of the granitic rocks described above. These anal-
yses present several points of interest, chief among which may

A. TABLE OF CHEMICAL ANALYSES.

GRANITES.
I lly III IVz V VI§ VII||- VIII
Stone lLexing- Green- Oglesby Campbell Elber- Coweta Meriw’r
Mt. ton ville county ton county county

SiOz 72.56 69.95 69.88 69.86 69.55 69.17 68.98 63.27
Al2O3’ 14.81 16.08- 16.42 16.98 16.72 16.54 16.90 19.93
Fe203* 0.94 * 1.21 1.96 1.31 O:99R paltas 1.25 2.82

CaO 1.19 2.38 1.78 1.99 1.69 1.99 2.28 2.89
MgO 0.20 0.56 £0.36 0.51 O27 O45° (O90) 049
K20 9:30 5.07 5.63 5.04 3.94 4.66 4.72 4.85
Naz20 4.94 4.84 445 4.77 5.88 4.60 4.98 4.14
Igni. O70. -. 0.77. > 0:39: ~0,36, 0:27 0.41 0.62 0.86

Total 100.64 100.86 100.87 100.82 99.31 99.20 100.63 99.25
Sp.Gr. 2.684 2.666 2.662 2.663 2.658 2.656 2.694 2.739

PORPHYRITIC GRANITES.

IX de XI XII XIIIT{ XIV XV
Fayette Pike Columbia Baldwin Sparta Fulton Greene
County County County County County County

Si0e 10:38 70:24 « 69:77 69.37 69.33 69.17 69.13
Al2O3’ —- 115.86 16.78 17.05 16.99 16.26 16.47 17.14
Fe203* ISTE 1.46 1.60 1.99 1.84 1.23 1.52

CaO Ife) 2.00 2.21 2.03 2.28 2.02 1.85
MgO 0.93 0.76 0.99 0.84 0.36 0.61 0.79
K20 4.64 5.03 4.08 4.54 4.56 4.41 5.49
Na2O 3.94 3.70 3.97 3.44 5.07 4.89 4.06
Igni. 0.49 0.50 0.44 0.55 0.42 1.06 0.52
Total 99.80 100.47 100.11 99.75 100.12 99.86 100.50
Sp. Gr. 2-659) eee DIGCEs sei eccss: POY AS VaM A Rted =) Serctionnc

* Alliron estimated as FesOg.
} Average of 3 analyses representing different quarries.
. iad ae 5 aé te ae ay

x
§ of of 3 oe oe ae ae

>
! oe Co se ‘ ae ae
I 3 ;

q “e “e 3 “ec “é se ae

’ Contains traces of P2O5,TiO2 and ZrOz when present. With sever-
al exceptions, the usual qualitative test failed to indicate the presence
of TiO2 in the Georgiaacid rocks. F205 and ZrO2 are invariably present
in small microscopic proportions as prismatic inclusions of apatite and
Zircon. \

SiOz

Piedmont Plateau of Georgia.—Watson. ray

GNEISSES.,
PT DOVE: EVES * SEX ES OE. SOE ROCHE

Meriw’r Gwinnett Rockdale Heard Lithonia Coweta Newton Clarke
County County County County County County County

76.37 75.86 75.45 7496 74.70 73.95 71.20 69.51

AlsOs’ 13.31 14.02 13.71 13.71 13.85 14.23 15.46 16.32
Fe203* 1.21 Ohba 0:92) AC © 1-05. (1229 i 1ig 238

CaO
MgO
K20
Na20O
Igni.

Total

ite. \O2f0 O194-- 5.02 1.08 1.07 1.36 1.84

100.02 100.89 99.77 100.74 99.87 100.92 100.30 99.73

ers) 2.062, 2.642'" 2.643 2.648: 2.686 9... cccdece tacts

SiO2
Al203
Fe203
CaO
MgO
K20
Na20O
K20
Naz2O

SiOe
AleOs
Fe203
CaO
MgO
K20
Na2O
K20
Na20

SiOs
Al2O3
Fe203
CaO
MgO
K20
Na2O
K20
Na20

* All iron estimated as Fe20g.

B. MOLECULAR RATIOS OF THE OXIDES.
GRANITES

I II III IV V VI VII VIII
eco to 165s 1.164. 21.164 1:159' 1.152 1.149 1.054.

145 .156 .160 164 .163 .160 .164 195

.005 007 .012 .008 .006 .008 .007 .017

021 .042 .032 .035 .030 .035 .040 .051

.005 .014 .009 .012 .006 011 .022 AD

.056 053 .059 .053 041 .049 .050 .051

.079 .078 O71 .076 .094 .074 .080 .066

\ es 141. $1300. 4.199" 185... .124°°. 130). 147

PORPHYRITIC GRANITES

IX D.€ XI XII XIII XIV XV
1.181 1.170 1.162 1.156 1.155 1.152 1.152
155 .164 .167 .166 157 .163 .168
O11 .009 .010 .012 O11 -007 -009
.032 .035 .039 .036 .040 .036 -033
.023 .019 .024 021 .009 -O15 .019
.049 .053 .043 .048 .048 -047 .058

.063 "059 .064 .055 .081 .078 .065
; 112 2 .107 -103 129 125 123

GRANITE—GNEISSES
evi oe VIP Se VILE EXD me SO Sy eX | REDE

1.272 1.264 1.257 1.249 1.245 1.232 1.186 1.158
.130 137 134 (134 134 .139 151 .160
.007 .004 .005 .005 .006 .008 -007 .014
.020 .012 .016 .018 -019 .019 -024 029. .
.002 .003 .004 .006 004 .005 .008 .010
039 .059 045 -050 .051 .026 .056 .044.
.064 .058 .062 .075 .063 .074 .080 .070

; .103 ita .107 125 L1L4 110 136 114

° Average of 3 analyses representing different quarries.

’ Contains traces of P2O5, TiO2 and ZrOz when present. With sever-
al exceptions, the usual qualitative test failed to indicate the. presence
of TiOz in the Georgia acid rocks, P20s5 and ZrO2 are invariably present
- small microscopic proportions as prismatic inclusions of apatite and

ircon.

218 The American Geologist. April, 1901.

No.of K20: Na2O No.of K20: Na2z0 No. of K20: Na20O
Anal. Anal. Anal.

recs 1: 1.41) Ti ssinee Pel ea eee 1: 1.64

rt oe 1:1.47] er Eee 1:1i1/oS | XVI ee
EIT’... 13, eee he ee ee 1:149)/25 XVIIL....1: 137] 9@
Va 1:1.43[5 Sines 38> 1: 1.1472 a 2 xm =: 1:1.50(8¢
Vee 1:.2.281 3 m9 fb ea 1:1.68) 3% DD SE 1: 123(22
Vin 1151/8 XIV...1:165/@8 XXL....1:307/a8
Vito 1 SR6Ol ia oe 1:112) O Xx See
VIII....1 : 1.29] XVIII......2 eon

be mentioned their marked uniformity or very close agree-
ment throughout for the three rock phases. A distinguishing
feature is their relatively high percentage of Na,O, which is
observed to be above the average for normal granites. The
percentages of Na,O and K,O approximate nearly equal
amounts in a majority of the analyses, but in many the K,O
exceeds the Na,O, while in others the Na.,O is in considerable
excess over the K,O. The high Na,O in the Georgia granites
is traceable to'three sources: (1) the presence of comparatively
appreciable amounts of single laths of an acid plagioclase; (2)
the abundance of microperthitic intergrowths of the potash
feldspars with a second feldspar, probably albite; and (3) in
the potash feldspar varieties, a part of the potassium is re-
placed by sodium. See analysis on page 209. The general
high range in total alkalies—Na,O+K,O—is a very note-
worthy feature in the analyses. The general average for total
alkalies is from 8.79 per cent. in the gneisses to 9.44 per cent.
in the granites.

For the sake of ready comparison the following percentages
obtained from the average of 21, 10 and 12 analyses, respect-
ively, of the normal granites, porphyritic granites and granite-
gneisses are hereby tabulated :

Si02 <AlzOg Fe20g3 MgO CaO NazO K20O
Normal granites...... 69.67. 16.63 1.28 "0:55 “2:16-4:73 > 4a
Porphyritic granites 69.28 16.73 1.75 0.72 2.13 4.33 4.59
Granite-gneisses...... 13.76" 14.52" 2.03 “0/29 dit4) 4G Sees

No appreciable difference is noted in any one of the seven
constituents in case of the normal granites and their equiva-
lent porphyritic facies, but a comparison of the analyses of the
granite-gneisses with those of the granites, discloses several
interesting differences among the more important constituents.
An increased percentage of about 4 per cent. in the SiO,, and
somewhat regular corresponding decreased percentages in the

Watson. 219

Piedmont Plateau of Georgia.

Al,O, and CaO, and to a less degree in the Fe,O,, and MgO
over the two granite facies, are shown in the granite-gneisses ;
while the alkalies—Na,O + K,O—remain very uniform and
constant for the three rock phases.

It will be further observed from an examination of the table
of individual analyses, that with one or two exceptions the
Georgia granitic rocks are normally acid granites, showing a
general average of approximately 70 per cent. in SiO,, while
the percentages of iron and magnesia are somewhat below the
general average for normal granites.

The molecular ratios of the oxides given above show a
tendency in the Al,O,, Fe,O, and CaO to gradually increase as
the SiO, decreases for the three rock phases. The gradual
rise in Al,O, with decreasing SiO, is well illustrated in the
case of the granite-gneisses. The table of molecular propor-
tions further shows the alkalies in sum total remain fairly con-
stant with only slight variation.

These statements would seem to indicate, that no absolute
relation exists between the Al,O,, SiO, and alkalies, since the
tendency is for the Al,O, to increase as the SiO, decreases,
while the Na,O + K,O remain approximately the same.

3. MINERAL COMPOSITION.

From the preceding descriptions, the Georgia granitic rocks
are seen to be made up of mixtures of the essential minerals,
quartz, feldspar and biotite, with varying amounts of mus-
covite intimately associated with the biotite. The potash feld-
spar varieties predominate; and, in two cases, biotite is sub-
ordinated to muscovite. The entire absence of hornblende in
these rocks is a marked feature. Besides these, the usual ac-
cessory minerals common to granite rocks in general, occur,
and have already been mentioned. The relative proportions
of the essential minerals in the granites, excepting the Stone
mountain type, may be expressed thus: Feldspar including ali
varieties present > quartz > biotite > muscovite. For Stone
mountain the proportions become: feldspar > quartz > mus-
covite > biotite.

There is nothing especially noteworthy about the bulk of
the minerals present in the Georgia acid rocks, and therefore,

220 The American Geologist. Apel, Aen

they do not require extended details further than given under
the descriptions of the various granite-types. There are sev-
eral minerals present, however, which from their association
and conditions of environment require further descriptions.
These are microcline and muscovite.

The prevalence of intergrowths with a second feldspar
common to the three rock phases, in case of orthoclase and to
some degree microcline, in the form of microperthitic struct-
ures, has already been remarked on under the descriptions of
the individual types.

MicrocLine: The abundance of feldspar grains showing
the characteristics cross-grating structure is a striking feature
in most thin sections of the Georgia granites. The twinning
lamellz thin out in many cases, and do not always show per-
fectly parallel sides. Crystals are often met in which the
microcline structure is developed in only a part of the individu-
al and entirely failing in the other parts, leaving the untwinned
area optically indistinguishable from orthoclase. These granites
have been subjected, as elsewhere shown, to intense dynamo-
metamorphism, which fact, coupled with the prevalence of this
feldspar, affords strong indications of a part of this mineral
having acquired its structure. A part of the microcline is un-
questionably primary. Similar conditions are recorded in
granite masses in ditferent localities by various writers.*

Muscovite: Since the occurrence of primary muscovite
in an eruptive granite has been questioned, it is of interest to
note a similar occurrence of this constituent in many of the
Georgia granites to that observed by Keyes} in some of the
Maryland granites, where primary origin affords the best ex-
planation. In many of the Georgia granite areas, especially
the Oglesby-Lexington dark blue granite area, large and
sharply bounded plates of fresh appearing muscovite, are dis-
tributed through the rock in intimate association with the bio-
tite. The two micas are frequently grouped together as agegre-
gates in which the individuality of the separate crystals is well
preserved. They not infrequently form parallel intergrowths,

* KEYES, C. R., 15th Ann’! Rept., U. S. G. S., 1893-94, pp. 711-712.
VON RINNE, NEUES JAHRB, ii, 1890, pp. 66-70.
BEUTELLE, ZEITSCHR. f. Kryst, viii, p. 373.
SAUER & UssING, Ibid, xviii, 1891, p. 196.
BROGGER, Ibid, xvi, 1890, p. 561.

+ KEYEs, C. R., 15th Ann’! Rept., U. S. G. S., 1893-94, pp. 703-704.

Quoted by Keyes.

Piedmont Plateau of Georgia.—Watson. 22t

and at times the distinctly bounded muscovite plates penetrate
and cut across the biotite foils at various angles. The relations
of the two micas to each other, very strongly point to contem-
poraneous crystallization of the two minerals. The large shreds
of supposed primary muscovite are in marked contrast in the
Same section to the muscovite of known secondary origin asso-
ciated with kaolin, and resulting from feldspathic alteration.
The cleavage lines are less distinct, and the muscovite presents
greater irregularity of outline in case of the mineral of sec-
ondary origin. Still another portion of the muscovite in a
part of the Georgia rocks has developed as a result of dynamo-
metamorphism, and it is not always easy to distinguish between
this and the same supposed primary constituent.

The marked similarity in mineral composition of the gran-
ites and gneisses is plain from the above descriptions. No
mineral is found in one, that does not occur in the other; and
those minerals most abundant in one predominate in the other.
Their mineral composition conforms in every essential to that
of known igneous granites occurring elsewhere. They are
composed of minerals which most commonly make up the
masses of normal eruptive granite. Not a single mineral
among the list of primary and essential ones are included in
the three rock phases, that does not characterize an igneous
granite. The essential minerals are present furthermore, in
the usual proportions common to such rocks. The rock types
studied are entirely free from such minerals as staurolite, and-
alusite, cordierite and kyanite, frequently characteristic of
sedimentaries. Garnet is sparingly present in some of the
granites and becomes very abundant, in places, in a part of the
gneisses, but it is unquestionably, in these cases, a product of
metamorphism, and is as readily produced by such action, in |
igneous rocks, as in sedimentaries.

Hardly without exception, the thin sections of these rocks
disclose an abundance of ovals or rounded disks of micropeg-
matitic structures—intergrowths of feldspar and quartz—
which from their nature, in this case, are unquestionably re-
ferred to a primary product of the magma, and therefore rep-
resent simultaneous crystallization of the quartz and feldspar.

WEATHERING: Not only are the three phases of granitic
rock alike in the above respects, which are in accord with sim-

222 The American Geologist. April, 100m

ilar rocks of igneous origin, but the form and manner of weath-
ering are those of igneous rocks. The more perfectly banded
phases,—gneisses—weather in process and topographic outline
closely similar to the massive granites. The chemical and
physical processes involved in the disintegration and decom-
position of these rocks are the same, and are described and dis-
cussed elsewhere.*

RESUME: From the preceding facts, there can apparently
be little question as to the origin of the granites and their band-
ed equivalents. The rocks appear like eruptives in the field.
The clastic grains, when present and seen in thin sections of
the foliated phases—gneisses—are evidently dynamic in ori-
gin; all are sharply angular, and none have the outline of
water-worn grains. The structure of the gneisses is similar to
that of like rocks occurring elsewhere, and shown to be meta-
morphosed eruptives. Therefore, since they conform with
such regularity in mineral and chemical composition, and field
evidences as well, to the massive granite type, there can be no
reason for believing them to be anything but altered igneous
rocks. No evidence of any kind is, at present, apparent to
support the belief that the gneisses so far studied are water-
deposited sediments, subsequently recrystallized by metamor-
phic processes.

As to the origin of the massive granites and their equiva-
lent, porphyritic phases, there can be no doubt.

STRUCTURAL FEATURES: ‘The structural phases of the var-
ious granite types have already been noted. Joint planes are
very common in many of the larger masses and are as a rule,
only slightly developed in others; and they traverse the rock
with great regularity. They may conform to several different
directions but usually they have uniform directions over the
entire region. The best developed ones have nearly due east-
west and north-south courses, approximating in some quarries
northwest-southeast directions. Considerable subsequent
movement in the granite-masses is manifested in many of the
larger quarries, in pronounced slicken-sided surfaces of the
joint planes. The slickened surfaces are, as a rule, coated with

* Read by title at the Albany, N. Y., meeting of the Geological Soc. of Amer.,
and presented in abstracted form by DR. Gro. P. MERRILL.

A preliminary report on the granités and gneisses of Georgia by T. L.
WATSON, Geol. Sur. of Ga., in press.

Piedinont Plateau of Georgia.—lW atson. 223

a moderately thick veneering of perfectly smooth, somewhat
yellowish-colored sericitic material, frequently more or less
grooved and striated from the movement.
Two sets of intersecting material differing widely in texture
and mineral composition, and in origin, are common to the
granitic rocks. These are: (1) True granite dikes, which vary
in width from a few inches to many feet, cutting the rocks in a
nearly vertical position; are dark blue in color, and fine even-
granular in texture; and are composed of the same minerals
in the same proportions, and have the same chemical composi-
tion as the even-granular granites. [Plate XXIV.] Since
this class of intersecting material is not found in the more mas-
sive adjacent granites it is regarded in the nature of apophyses
from these massifs. (See page 214 for chemical analysis.)
(2) True pegmatitic dikes and veins of variable dimensions are
common to the three rock phases and are composed of coarsely
crystallized feldspar and quartz, with varying small propor-
tions of the two micas, biotite and muscovite. [Plate XXII.}
These are described in some detail on page 215.

AGE RELATIONS OF THE GEORGIA GRANITIC ROCKS,

No sedimentary rocks whose age is definitely known occur
in the Plateau-crystalline-complex to admit of the definite de-
termination of the age of the granites. In the absence of such,
we can only hope to arrive at their relative ages by careful
study of the contacts and the relative amounts of dynamic met-
amorphism the rocks have suffered. <A careful field examina-
tion of the granitic rocks in the Plateau region of the state,
shows considerable contrast in the amount of foliation or band-
ing secondarily induced by pressure. All thin sections of the
rocks studied showed some evidence of dynamo-metamorphism.
This evidence is detailed above. The strongly banded gneisses
differ from the massive phases of the rocks, simply in the pro-
nounced schistose structure. In some areas of the massive
granites an imperfect partial gneissoid structure is visible,
which becomes rather noticeable in the Stone mountain area.

While no case has been observed in the field, where the
highly contorted gneissoid phase was definitely traced into the
massive type, owing perhaps, if they exist, to lack of exposures
there are a few areas where conditions very strongly point to

224 The American Geologist. Apel, re

such gradation. Hayes* has described an extensive porphy-
ritic granite area near the Cartersville fault in Bartow county,
Georgia, in which the gradation from partially massive to a
highly schistose granite is plainly visible. The stratigraphic
relations of this igneous mass, to the surrounding sedimentaries
of known age, cannot be mistaken, and Hayes has shown the
intrusive granite, subsequently rendered highly schistose from
intense pressure metamorphism, to be pre-Cambrian—Archzan
—in age.

There appears to be, however, in most cases a sharp line of
demarkation between the massive and slightly gneissoid gran-
ites, and the extreme foliated gneisses. In many areas where
the schistose and massive granites occur, a part of the gneisses
are cut by true granite dikes having the same mineral and
chemical composition, as the massive granites, which they re-
semble in every respect. As elsewhere stated, the dikes are re-
garded as probable apophyses from the massive type of rocks.
If then schistose structure secondarily induced or degree of
metamorphism be taken as an index to age relationship, in the
case of the Georgia granitic rocks, and accepting the evidence
so strongly pointing to igneous origin for the highly banded
gneisses, at least two different periods of intrusion of closely
similar acid material are represented. The query naturally fol-
lows then whether all of these rocks have originated from the
same parent magma?t Chemical and mineralogical composi-
tion more than suggest such condition.

A very close relationship in mineral and chemical composi-
tion is observed in the Georgia granites to similar rocks exist-
ing to the north in the Atlantic Coast region. Kemp,? after a
careful study of our present knowledge of the Atlantic Coast
granites, has emphasized the great predominance of mica-
granites, especially the biotitic types over others; and, with
other investigators§ has remarked their definitely known in-
truded character at different geological periods. Keyesf re-
marks in his studies of a part of the Maryland granites : “Certain
ears 4200. W., Trans. Amer. Inst. Min. Engrs., Washington meeting,

J ee ES oe Geol. Soc. America, 1899, vol. x, p. 382.

§ WtLuiaAMs, G. H., 15th Ann’! Rept., U. S. G. S., 1893-94, pp. 666-670. DR.
WILLIAMS reviews the distribution and relative ages of igneous granites in the
Appalachian Crystallime belt and, gives numerous bibliographic references

thereto.
{ KEYEs, C. R., 15th Ann’l Rept., U. S. G. S., 1893-94, p. 733.

Piedmont Plateau of Georgia.—lWatson. 225

it is that the acid eruptives [granites] were among the last
igneous intrusions to disturb the rocks of the eastern Piedmont
Plateau.” The same author states in a preceding sentence,
that the granite may have been intruded as late “as the last
great disturbance of the region preceding the Appalachian
uplift.”

After a study of the Newark rocks of the “Richmond basin”
in Virginia, Shaler and Woodworth,* in commenting on the
age of the underlying rocks or “fundamental plexus’, including
granites and gneisses, say, “they probably date to Laurentian
or Huronian time.” (p. 418). And again on nage 421 of the
same report, the authors say, “The age of these rocks [granites
and gneisses] is not locally determinable.” The granites and
gneisses of this area were grouped by Rogerst as Archzan.

Field and laboratory study of the granitic masses in the

_ Georgia area certainly indicate, that they were not all con-
temporaneous in origin. Some of them are pre-Cambrian,
while others may possibly be later in age. The youngest acid
intrusives could not have been later however, if as late, which
appears improbable from the existing facts and conditions, as
the last great Appalachian disturbance or uplift.

Whatever age or ages be assigned the granites of this reg-
ion, it is certain that the most massive types of the rocks exhibit
strong proofs of mechanical strain, which indicates that since

the intrusion of the last granites the region has suffered pro-
found metamorphism.

METAMORPHIC FORMATIONS OF NORTHWEST-
ERN CALIFORNIA.

By Oscar H. HERSHEY, Berkeley, Cal.
INTRODUCTION.

That portion of the Klamath mountains lying west of
Shasta county, California, is not quite a terra incognita to geol-
ogists, as it was visited by one of Whitney’s exploring expedi-
tions? and has since been partially studied by Diller,$ Fair-
banks, || Anderson and the writer; but all that has been written

* 19th Annual Report, U.S. Geol. Survey, 1897-98 (1899) Pt.ii, pp. 385-515.
+ Geology of the Virginias, 1884.

t Geological Survey of California, vol, i.

§ Fourteenth Annual Report, U.S. Geol. Sur. pp. 403-448.

|| Bulletin of the Geological Society of America, vol. vi, pp. 71-101.

226 The American Geologist. April, 20g

about it was of a rather desultory character, hardly calculated
to give one a comprehensive and correct knowledge of its geol-
ogy. The present writer has been engaged in prospecting
for the precious metals in the Klamath region for nearly
two years, during which many sections of the territory have
been traversed and although there was not carried on a sys-
tematic study of any particular geological problems, it has
resulted, it is believed, in the accumulation of sufficient knowl-
edge of the structural relations of the formations of that re-
gion to make possible a classification of the metamorphic rocks.

DESCRIPTION OF FORMATIONS.

The pre-Cretaceous rocks of the entire Klamath mountain
region (aside from the eruptives occurring in batholiths and
dikes and unquestionably of an intrusive character) may be
classified into seven great formations as in the following table
which represents their structural positions although not nec-
essarily their age relations:

1. The Upper Slates or Bragdon formation.

2. The Greenstone or Clear Creek formation.
3. The Lower Slate Series

4. The Hornblende Schist or Salmon formation.

5. The Mica Schist or Abrams formation.

6. The Serpentine or Trinity formation.

7. The Gabbro or Tamarack formation. *

The structural relations and age of the serpentine consti-
tute the great problem in the geology of the Klamath region.
In the Coast range region a petrographically similar serpen-
tine is an altered peridotyte, unquestionably intrusive in the
Franciscan series, of an age at least not earlier than the
Jurassic; but in the Klamath region I cannot find the same
evidences of the serpentine being intrusive in the metamorphic
sedimentaries. The subject is a complex one, and requires
further field work for its solution; hence, in this paper I shall
confine.my attention to the schists, slates and associated forma-
tions.

The Abrams mica schist—Large bodies of schists of a
prominently micaceous character are not of common occur-
rence in the rocks of the Klamath region except as constitut-
ing a single well-defined formation, for which from its relations
to neighboring terranes being best worked out in the upper

Californian Metamorplic Formations.—Hershey. 227

Coffee Creek region, I propose the name of the Abrams post-
office of that section. It is composed of thin folia of muscovite
of dull colors, such as gray, light brown, yellow and dull red,
separated by irregular layers of white quartz, representing
the original lamine. Throughout it is very highly siliceous and
doubtlessly portions of it would by some be called mica-
ceous quartz schist. In certain belts the silica predominates
to such an extent as to cause it to outcrop like great veins of
very glassy, white and dark blue quartz. The relatively great
amount of this primary quartz is particularly characteristic of
this formation. There are, also, in places thin folia of hard
blue crystalline limestone, sometimes thickening and clearing
to a beautiful white marble. The foliation of the formation is
parallel to the top and bottom and in general to the original
lines of stratification.

This particular schist formation occurs in a long narrow
belt bounding the great serpentine area of northeastern Trinity
county on the west. Beginning somewhere in Siskiyon coun-
ty, west of Callahan, it runs continuously in a southerly direc-
tion across the valley of Coffee creek, the head of the south
fork of Salmon river, and thence through the mountains just
a little west of Weaverville. From here its course is south-
easterly in conformity with the strike of all formations in
southern and western Trinity county. The cafion of Weaver
creek is cut principally into it and it is finely exposed along
Trinity river near Douglas City. From here southward it
widens out into a belt several miles in width and constitutes
the mass of Bully Choop mountain, on the southern slope of
which it sinks beneath the Cretaceous formations of the Sac-
ramento valley.

In the southern portion of this schist belt it appears to be
folded into at least two main anticlines along the axes of which
serpentine outcrops in the form of narrow belts constituting
the so-called dikes. I wish particularly to call attention to the
fact that serpentine is commonly associated with this mica
schist formation. The normal succession of the strata in the
direction of the dip is invariably serpentine, mica schist and
hornblende schist.

Another narrow north-south belt of mica schist crosses the
south fork of Salmon River valley at the village of Cecilville.

228 The American Geologist. April, aus

Here it is bounded on the east by the great hornblende schist
formation and along its west border occurs a narrow belt of
serpentine.

The only remaining area of this formation known to me is
developed in the vicinity of Yreka and Fort Jones in Siskiyon
county where again it is associated with serpentine.

The thickness of the Abrams mica schist in the upper
Coffee Creek section is estimated at about 1,000 feet, but it
seems to thicken to the southward and at Bully Choop may be
much greater.

This is undoubtedly a highly metamorphosed sedimentary.
Originally it was a series of argillaceous sandstone beds in
large part finely laminated. The action of the metamorphism
has been to convert the nearly purely siliceous laminz into
quartzyte layers, while folia of mica were developed in the shaly
partings between the layers. In portions of the formation
shearing such as usually produces schistosity has been nearly
absent and the structure is rather that of a shale than a true
schist. Yet this thermometamorphic action has been so in-
tense that the original detrital granular nature of the material
has been completely destroyed. Certain pure quartz sand
layers have been converted into the apparent large quartz
veins, which have a definite position in the series, are always
parallel to the strike, and grade upward and downward into
the distinctly laminated schist, yet rarely display the sub-gran-
ular texture of a typical quartzyte.

The Salmon hornblende schist. Whenever the boundary
between the mica and hornblende schist has been examined
by me, as in the south fork of Salmon River country and the
Hay Fork section south of Trinity river, the former was found
to grade into the latter through a thin series of graphite schist
and actinolite schist. The black graphitic schist is particularly
characteristic of this horizon and occurs nowhere else in the
series. It was originally a highly carbonaceous layer in the
succession of sandstones and shales and probably deposited un-
. der much the same conditions as veins of coal in the carbon-
iferous rocks. The actinolite schist, so far as my observation
goes, is also confined to this horizon. Usually it is of fine tex-
ture, light green in color and has a peculiar bladed structure,
but locally there is developed a coarse-textured type yielding

Californian Metamorphic Formations.—Hershey. 229

fine specimens of crystalline aggregates of actinolite. The
graphite and actinolite schists combined usually have a thick-
ness of no more than five to fifteen feet and in the presence of
the broader belts of other schists on either side may escape de-
tection in many sections unless especially searched for.

The hornblende schist is remarkable for its uniformity
throughout a thickness of probably not less than 2,500 feet. It
consists of elongated or blade-shaped crystals of dark green
and black hornblende, separated by irregular thin layers of
white quartz, with feldspar locally developed. It is moderately
fine-grained and its general color is a dark green; it outcrops in
rugged peaks of black rocks. Certain layers are highly calcar-
eous, abounding in curiously contorted folia of crystalline lime-
stone, even increasing to one- and two-foot layers of impure
marble. Much of the formation has a schistosity developed by
shearing, but in places the original lamination can be distinctly
discerned and it is often highly contorted. There are other
portions in which quartz is nearly absent and the rock consists
of massive aggregates of comparatively coarse hornblende crys-
tals, producing a type resembling a truly igneous hornblendyte.
Indeed, hand specimens of this formation have frequently been
identified as dioryte and even some’ who correctly discriminate
it as hornblende schist consider it an altered igneous rock. I
propose to show that it is a highly metamorphosed sedimentary.

The largest area of hornblende schist is traversed by the
south fork of Salmon river between its head and the vicinity
of the village of Cecilville. It constitutes a broad, shallow,
synclinal trough, trending north to south and probably ten
miles in width. On each side the strata are upturned to the ex-
tent of allowing the mica schist to come to the surface from un-
der them. Both north and south from the river the synclinai
is further disturbed by the upthrust of the hornblende schist
against huge batholiths of granite and quartz-mica-dioryte
At the center of the structural basin thus formed, the forma-
tion has been less modified by metamorphic action than usually.
The strata are but little tilted and the original bedding planes
are quite distinct. Before its conversion into hornblende
schist it passed through a stage of thin-bedded slate, the
structure lines of which yet remain. Interbedded with the
schists there is a two to four-foot layer of dark gray, fine-

236 The American Geologist. April, 1005

grained compact quartzyte. In several places this shows shaly
partings. Undoubtedly there is here evidence of the clastic
character of the formation.

In the Hay Fork section of Trinity county, the Salmon
hornblende schist is well developed as a belt several miles in
width lying between the mica schist on the east and the black
schistose slates of the Devono-Carboniferous on the west. In
this area the schistosity is not so strongly developed and much
of the formation is but little removed in alteration from a slate.
In many places the bedding planes are distinct and indicate a
formation originally not finely laminated nor yet very heavily
bedded.

Another area of this formation occurs on the east side of
the great serpentine area of the Sierra Costa mountains, on
Rush creek several miles north of Weaverville.

We may now take a broader view of the schist series. The
members are everywhere perfectly conformable to each other
and evidently represent continuous sedimentation. At the base
was an argillaceous sandstone with certain single heavy strata
of nearly pure quartz sand. Following that was deposited a
thin stratum of highly carbonaceous and siliceous shale. An-
other change in conditions brought in a more argillaceous and
calcareous sediment and then followed a long period of remark-
ably uniform deposition of shale, sandy layers being few and
fine in texture. All members of the series have been subjected
to the same degree of metamorphism. Without shearing ex-
cept locally, the first member was recrystallized into micaceous
quartz schist, the second into graphite schist, the third into
actinolite schist and the last seems to have passed through a
slaty stage into hornblende schist.

The discussion of the age of this Klamath schist series will
be reserved for the close of, the paper.

The Lower Slate series ——This is made up of a succession
of black slates, quartzytes and limestone. The slates nearly al-
ways have a schistose structure due to shearing. The quartz-
ytes make up a large part of the series and are fine-grained
and often regularly and thinly bedded. The granular structure
and detrital origin are quite apparent to the unaided eye. The
beds of quartzyte alternate rapidly with the schistose slates.
The limestones occur in long narrow dilke-like masses which are

Californian Metamorphic Formations.—Hershey. 231

often repeated three or four times in parallel lines within sev-
eral miles transverse to the strike of the slates, apparently as
the result of folds or faults. Some of these “lime dikes” have
a width of several hundred feet and stand out boldly above the
surrounding slates. The limestone is usually massive and
crystalline in character. Generally the metamorphism has
proceeded to such an extent as to have completely destroyed the
fossils, but near the Sacramento and McCloud rivers this is not
the case, and there the limestones furnish the material for the
determination of the age of this series.

The areas of the Lower Shale series are characterized :—

1. Bythepeculiar outcrop of the quartzyte ; the surface of the
hills abounds in fragments of cherty quartz either stained to
light tints of red, yellow or brown or having a whitish, bleached
appearance. It is difficult to convey an_accurate impression of
what is here meant, but it is a feature universally present in
all the areas of this series no matter how widely separated or
whether representing its upper or lower members. No other
formation outcrops in quite the same way although internally
it may resemble this.

2. By abundant dikes of greenstone intruded into the
series and cutting across the stratification.

3. By the belts of limestone. Limestone and marble occur
in the earlier. schists but are insignificant in development in
comparison with those of the Lower Slate series.

4. By a certain degree of dynamo-metamorphism which
is comparatively uniform throughout the series and is of the
nature of regional and not local or contact metamorphism.

The formation is commonly contorted, faulted and sheared
throughout. Much of the argillaceous material has been con-
verted into hornblende and micaceous minerals, but this is not
macroscopically prominent. The sandstones have been partial-
ly recrystallized and thoroughly lithified. The limestone has
usually been altered to a distinct crystalline aggregate pre-
senting little evidence of its original condition. The general
appearance of the series is one of practically the same age
throughout, and as a whole much older than the Mesozoic
slates, to be described later, and much newer than the schis*
‘ series, discussed in preceding ‘pages.

In Trinity county, the Lower Slate series is chiefly cdevel-

232 The American Geologist. April, 1004,

oped in a belt lying just west of the hornblende schist, trend-
ing from southeast to northwest from the vicinity of Harrison
Gulch in Shasta county, across the Hay Fork country and the
Lower Trinity basin, and crossing the divide into Siskiyon
county in the New River mountains. It is traversed by the
south fork of Salmon river below Cecilville, where much of the
country over a width of ten or fifteen miles belongs to this
series. The belt probably averages about five miles in width.

The next principal area is in the Scott Valley region, be-
tween Fort Jones and Callahan, and extending thence east to
Shasta valley near Gazelle. The Sacramento cafion cuts a
number of small areas of this formation between Castella and
Delta, and it largely occupies the country east of the river to
and beyond the McCloud river.

The age of the series is pretty definitely known through
fossils occurring in it near the Sacramento and McCloud rivers
and studied by Trask,* Walcott, Smith,y Diller, Schuchert,=
Anderson and others. A small area near Kennett is considered
Devonian in age, and in limestone near Gazelle has been found
a fossil fauna indicating still lower Devonian. I understand,
also, the Devonian fauna occurs in the series in the Scott Val-
ley region. On the McCloud river a Lower Carboniferous
fauna is found in the Baird shales and an Upper Carboniferous
in the McCloud limestone. Prof. J. P. Smith has informed me
that farther up the McCloud river there are fossils of a Per-
mian facies. Hence, it appears, that the Lower Slate series
ranges in age from the Lower Devonian to Permian, and as
there is no known stratigraphic break in the series, sedimenta-
tion was probably continuous throughout Devonian and Car-
boniferous time. Metamorphism in the McCloud region has
been somewhat less in intensity than in the southwestern Sis-
kiyon and Trinity areas. It is to be noted, however, that the
small Devonian area near Kennett more closely resembles the
series in Trinity county than thé Carboniferous area in the
McCloud, and the more aged appearance of the western areas
may be due not alone to their different situation in the range

* Report on the Geology of the Coast Mountains, 1855.

+ ‘*The Metamorphic Series of Shasta county, California,’’ Jour. of Geol.,
vol. ii, pp. 588-612.

t‘'Discovery of Devonian Rocks in California,’’ Am. Jour. Sci, III Series,
vol, xlvii, pp. 416-422.

Californian Metamorphic Formations.—Hershey. 233

but also to their representing the older or Devonian portion
of the series.

This series of slates, quartzytes and limestones certainly
represents in part the Calaveras formation of the Sierra Ne-
vada region, but also seems to include strata of the same age as
the Arlington and Robinson formations. The Devonian por-
tion of the series is not well represented in the Sierra Nevada —
region, but strata of that age have been discriminated there.
I should be inclined to extend the term Calaveras in its original
significance to the Klamath region if it had not come to be
restricted to a particular portion of the Devono-Carboniferous
series. It is doubtful if we shall be able to separate the Devon-
ian and Carboniferous components of the series in the south-
western Siskiyon and Trinity areas, and we may be obliged to
adopt a collective name synonymous with that which I have
used, the Lower Slate series.

The thickness of the series in any one section is not known
to me. Usually the succession of strata is repeated several
times in a single area by faulting and folding. It appears to
be considerably thicker than the schist series and than the later
Mesozoic slates, and an estimated average for the entire terri-
tory of 5,000 feet is probably sufficiently accurate for the
present.

The Clear Creek greenstone.—Southeast of the high rugged
peaks constituting the Sierra Costa range, there is a much
lower mountain country constituting the basin of Trinity river
between Trinity Center and Lewiston, the Trinity mountain
and the ridges eastward to the Sacramento river. The geolo-
gy of this extensive territory is comparatively simple and en-
tirely unlike that of the country to the west. Aside from the
intrusive granites and porphyries, the mountains are made up
of two formations, the Clear creek greenstone and the Bragdon
slates. The former is the foundation rock of the region and
upon it the slates have been deposited.

In general, the slate formation remains practically in its
original horizontal position except that it has been thrown into
a broad, shallow syncline, with an axis a few miles east
of the summit of the Trinity range; but, considered in detail,
it is much disturbed by faults and folds of small dimensions
so that locally it presents dips of high degree, in not a few

234 The American Geologist. April, 1901.

cases vertical and even overturned. This folding somewhat
obscures the fact that the greenstone is always under. the
slates and never intruded into them.

The whole black slate country between Trinity Center and
Lewiston has been thrown into a series of about ten anticlinal
folds, striking east to west through the Trinity mountain and
across the courses of Trinity river and Clear creek. Near the
center of the series the folds are closely oppressed and the
slates along the sides vertical. Now, if we follow the contact
between the greenstone and slates up the limb of the anticlinal
we do not have to climb more than 500, or at most 1,000, feet
above the Trinity river until we find the slates curving up over
the greenstone, and the mountains above are entirely of slate.
The maximum vertical range of the folding is probably 2,000
feet, and the more open folds may be included within 1,000 feet.
Thus the greenstone rises into view in the axis of each anti-
cline, and sinks beneath the valley under each syncline.

The greenstone formation is made up of a variety of de-
posits of a volcanic nature, but all having something in com-
mon so that it appeats over wide areas as a massive, fine-
grained dull green rock, outcropping in ragged cliffs and
weathering down into a reddish clay soil. Much of it is of a
detrital character, chiefly diabasic tuffs and ashes, although in
places it is brecciated and occasionally it has a conglomerate

structure. This latter is peculiar. It consists of rounded peb- .

bles of diabase cemented by similar material. Among the dia-
basic tuffs are undoubtedly sheets of lava, in places containing
amygdaloids. The formation has been much altered and
abounds in secondary minerals of which epidote is macroscop-
ically the most prominent.

Running through the greenstone areas are long broad belie
of a fine-grained white rock resembling certain quartzytes, but
apparently a felsyte or a devitrified rhyolyte. Commonly asso-
ciated with them are zones of impregnation of iron and copper
pyrites, the sulphides sometimes concentrating into large solid
bodies, such as the Iron mountain and Copper city deposits.

Along certain zones of shearing which trend usually east-
west and have a width of ten to hundreds of feet, the diabase
has been converted into’a light-greenish schistose rock which
appears to me ‘to answer the description of certain phases of

Californian Metamorphic Formations.—Hershey. 235

the amphibolyte schist of the Sierra Nevada region. Bands of
impregnation of sulphides are also commonly associated with
these shear zones.

Another modification of the diabase quite common along
Trinity river is into a very hard, fine-grained, purplish flinty
rock, perhaps due to silicification of the greenstone. In the same
region occur dikes of quartz-porphyry which cut the green-
stone but terminate abruptly at the base of the overlying slates.
In fact, the whole greenstone formation appears to be a series
of diabasic tuffs and lavas bound together by a variety of in-
trusive porphyries and diabase.

This greenstone in large part is beyond doubt extrusive in
character ; in other words, it is a formation of surface volcanic
material. It has its counterpart in the Neocene tuffs and lavas
spread widely over the older formations in the Cascade region.
On the isthmus of Panama, I have studied a great Neocene
volcanic formation of precisely the same character, except that
the tuffs are mainly rhyolitic and the lavas basaltic. The in-
ternal structure of these formations is characteristically alike.

The origin of the material of the greenstone has not yet
certainly been discovered. The Lower Slate series is particu-
larly abundantly supplied with dikes of greenstone scarcely dis-
“tinguishable from the main body of the diabase and in places
these intrusive diabases seem to pass into the extrusive forma-
tion. In the Cinnabar synclinal between the gabbro ridges
of northeastern Trinity county, great dikes of greenstone are
intruded into the serpentine and form extensive bodies along
the axis of the trough. The entire region from the Sacramento
river southwestward to the Hay Fork country and northwest-
ward to the lower Salmon river country appears to have been
overspread by this greenstone, for wherever its proper horizon is
-exposed, viz., between the Lower Slate series and the Bragdon
slates, heavy bodies of diabase occur as a stratigraphic unit
and not as intrusions.

Tuffs imply volcanoes and not mere fissure eruption. The
volcanoes of this period have disappeared, but I think they oc-
curred along a belt lying just west of the Sacramento river and
including the sites of, say, Kennett, Keswick, Shasta and. Cen-
terville. Here the formation is very thick and its fragmenta]
character is most apparent. Toward the westward it appears

236 The American Geologist. April, 1901.

to thin and become more uniformly a diabase similar to the
dikes in older formations. Its thickness is unknown, but in
Trinity valley it is at least 1,000 feet, as that thickness is ex-
posed and the bottom not seen.

The Clear Creek greenstone was deposited on land. At the
close of the epoch it suffered erosion and was levelled off either
by the sea, during the progress of the submergence to which the
slates are due, or by sub-aerial erosion, probably as the result
of both. This interval of erosion does not appear to have been
a long one. ;

The Bragdon slate.—This has its heaviest development in
the Trinity mountain (the bulk of which it forms) between the
high mountains east of Trinity Center and the vicinity of Lew-
iston. It is cut off on the west at the foot of the high Sierra
Costa mountains by a sharp monocline or a fault. On the east
it thins out because of erosion and has heen completelv re-
moved from over the greenstone formation along a broad belt
lying just west of the Sacramento river.

It is a series of alternating thin-bedded black slates and
thick-bedded blue quartzytes. As doubts have been expressed
that this formation is distinct from the Devono-Carboniferous
I will lay special stress upon the points of difference. In the
lower slates, the quartzytes are white and weather red, yellow,
brown or a bleached white; in the Bragdon slates, the quartz-
ytes are blue and weather gray. The former formation is schis-
tose throughout the argillaceous portion because of regiona!
shearing ; the Bragdon slates have only been sheared along cer-
tain zones, and most of the formation is merely a well lithified
or silicified shale and sandstone, without shearing. The Lower
Slate areas have limestone; the Bragdon slate areas none.
The former series abounds in intrusive diabase; the latter has
no dikes of this eruptive and all the diabase in its vicinity is
under it. Conglomerates are rare in the Devono-Carbonifer-
ous; in the Bragdon slates thin sheets of well-lithified, moder-
ately fine conglomerate are rather common, particularly in Hay
gulch, three miles north of Bragdon, and near French gulch.
The pebbles are of blue, black, red, yellow, brown and white
quartz and appear to have been formed principally from the
quartzytes, cherts and phthanytes of the Devono-Carboniferous.

Along the Sacramento river, near Elmore and thence east-

Californian Metamorphic Formations.—Hershey. 237

ward toward the McCloud river, there is a deposit of the Brag-
don slate. It contains conglomerates which on outcrop have
a singular-vesicular character, like an amygdaloid. Now there
are Devonian and Carboniferous limestones pretty strongly de-
veloped in that vicinity and I explain the rounded cavities in the
conglomerate by supposing that they represent pebbles of lime-
stone which have been dissolved out in the process of weath-
ering.

The conglomerates are most abundant toward the northeast,
and the whole formation seems to thin toward the southwest,
implying that the shore-line and source of the sediments were
somewhere on the northeast. In the Hay Fork country, lying
west of the Devono-Carboniferous, there is a narrow belt of
this formation. Here also it is closely associated with green-
stone, as in Trinity mountain. The two are folded into each
other and are separated by a sharp even line, with the green-
stone always stratigraphically under. Both greenstone and
slates are thinner than in the Trinity mountain area and the
latter average finer sediments.

The Bragdon slates were probably developed over the great-
er portion of the Klamath region, but through the vicissitudes
of elevation, folding and erosion, have been mostly destroyed.
This is the latest of the formations included in the ‘“Auriferous
Slate series” of northwestern California and probably the upper
limit of the original deposit nowhere remains. There are yet
over 2,000 feet in thickness of it in the Trinity mountain
country.

The age of the Bragdon slates 1s as yet somewhat uncertain,
as the formation has nowhere yielded any determinable fossils.
Along the road between French gulch and Trinity Center, near
Whitney’s ranch, there are traces of organic remains, apparent-
ly impressions of plants. However, no paleontological evi-
dence is available and I can only indicate what correlations arc
probable from the standpoint of lithology, stratigraphy and
structure.

In the Pitt River region, Prof. J. P. Smith has discrimin-
ated* a thick series of Mesozoic sediments included in part in
his Pitt formation and the Cedar and Bend formations, the lat-
ter of Jurassic age. There appears to have been essentially

* Jour. of Geol., vol. ii, pp. 558-612.

The American Geologist. ape

94)

continuous deposition from the Carboniferous through the
‘Triassic into the Jurassic. My acquaintance with that region
is slight, but when I visited it I could not so clearly separate
the Carboniferous and Mesozoic slates as in Trinity county.
My impression is that the latter formations are entirely unrep-
resented in Trinity county, their place being taken by a marked
interval of erosion. In the Pitt river valley I found the slates
grading into the greenstone by interstratification, while in Trin-
ity county they are distinct and a short interval of erosion be-
longs between them. My studies lead me to think that
throughout the Klamath region west of the Sacramento river,
sedimentation ceased at the close of the Paleozoic era and the
Devono-Carboniferous series was elevated into dry land, some-
what folded and metamorphosed and then greatly eroded, while
sedimentation continued through the Triassic and Jurassic per-
iods in the region of the McCloud and Pitt rivers, and thence
northeastward through an undetermined area. Sedimentation
in the country west of the Sacramento river was only resumed
well on in the Mesozoic era, after the Clear Creek volcanic per-
iod, and hence the greenstone and Bragdon slates (which
rightfully belong together as a series) came to rest unconform-
ably upon the Devono-Carboniferous.

Now, there is a remarkable resemblance in the lithology and
structure of the Clear Creek greenstone and the main diabase
and porphyryte formation of the Sierra Nevada region. Both
seem to represent a time when diabasic tuffs and lavas spread
over wide areas much as the Neocene volcanoes cover the older
formations in the Cascade region. In the Sierra Nevada re-
gion also this extrusive series of eruptives is intimately asso-
ciated with a black slate formation—the Mariposa slates of
late Jurassic age. Not only are the Bragdon slates litholog-
ically similar to the Mariposa slates, but the general make-up
of the two series is identical. This parallelism of conditions
on opposite sides of the comparatively narrow Sacramento val-
ley is too remarkable to be ignored. It seems to warrant the
correlation in a general way of the two series. As the Mari-
posa slates with their associated diabase and porphyryte are
considered late Jurassic in age, I shall provisionally class the
Clear Creek greenstone and the Bragdon slate as also Jurassic.

er kh

Californian Metamorphic Formations.—Hershey. 239

DISCUSSION OF THE AGE OF THE KLAMATH SCHIST SERIES.

The common association of serpentine with the Abrams
formation suggests that the peridotyte was intruded into the
slates and that the schists represent contact zones of meta-
morphism about it, and are merely altered portions of the De-
vono-Carboniferous series or the Bragdon slates. To this hy-

pothesis there are two fatal objections.

1. The original or unaltered sedimentary formations of the
schist series, the Devono-Carboniferous series and the Bragdon *
slate series were of a similar character petrographically (and
might be expected to yield like products under like conditions
of metamorphism) but the sequence of the strata was different.
No amount of metamorphism could have converted the Brag-
don slates or any portion of the known Devono-Carboniferous
into a series as the mica, graphite and hornblende schists. That
layer of graphitic schist is extremely important in this connec-
tion. By means of it and the nearly purely siliceous layers
outcropping as apparent large glassy quartz veins, we are able
to determine that the mica schist everywhere in the Klamath re-
gion represents the same portion of the original sedimentary
series, and the hornblende schist always a certain higher portion
while the recognized Devono-Carboniferous nowhere contains
representatives of this portion of the original sediments and the
Bragdon series is so very different as to be quite out of the
question.

2. Along several lines in the Klamath region the Devono-
Carboniferous and the schist series are in contact and “dikes”
or narrow belts of serpentine appear along these lines. On
Hay Fork mountain in southern Trinity county, a narrow belt
of the serpentine is bounded on the west as usual by mica schist,
followed by the graphite and hornblende schists. On the east
it is bounded by a belt of the characteristic schistose slate (cut
by greenstone dikes) of the Devono-Carboniferous. Now, if
the mica schist is an altered portion of the Devono-Carbonifer-
ous and due to the intrusion of peridotyte, why was the met-
amorphic action so very much more intense on one side of the
dike than on the other? These conditions are exactly repeated
along the boundary between the undoubted Devono-Carbonifer-
ous and the schist series in the vicinity of Cecilville and the
King Solomon mine in southwestern Siskiyon county, except

240 The American Geologist. April, 1901

that here the schists are on the east and the slates, quartzytes
and limestone on the west of the serpentine.

The serpentine is mainly confined to low levels, and higher
the slates and quartzytes rest directly on the mica schist and
the contact appears to be unconformable. It seems that the
schist series was tilted to the eastward at a considerable angle
and the Devono-Carboniferous laid down arcoss the beveled
edges of its strata. Similar evidence of non-conformity was
obtained on Hay Fork mountain. If the serpentine is older
than the schists there will not be any difficulty in demonstrat-
ing an unconformity indicating an immense erosion of the
schists previous to the deposition of the Devono-Carboniferous
sediments, but if the peridotyte was intruded into schists
and slates, the unconformity rests upon less definite evidence
and more work will be required to establish the fact beyond the
possibility of doubt. However, it is a fact that the typical De-
vono-Carboniferous comes close up to the typical schists and
they are separated by a sharp line, not the least evidence of one
grading into the other having ever been found.

Throughout the Devono-Carboniferous areas, narrow belts
or so-called “dikes” of serpentine are rather common. They us-
ually outcrop at lower levels, the schistose slates and quartzytes
apparently curving up over them as does the Bragdon slate
over the Clear Creek greenstone in the folds of Trinity valley.
One such strip of serpentine forming the axis of a narrow fold
occurs in Bridge gulch in the Hay Fork section. The typical
schistose slate and quartzyte of the Devono-Carboniferous
overlie it and may be traced to the very contact practically
unchanged. In the Scott valley region south of Fort Jones in
Siskiyon county, a sheet of serpentine appears to underlie the
Devono-Carboniferous over at least several square miles. Ia
no instance have I observed the development in these Devono-
Carboniferous areas of a mica schist or a graphite schist or a
hornblende schist along the contact, such as constitute the
Abrams and Salmon formations. It would be too remarkable
a case of selection to suppose that the peridotyte converted
thousands of feet of strata into mica and hornblende schists in
one area, and that in an immediately adjoining area, equally as
large masses of peridotyte failed to develop in the same strata
even a narrow contact zone of similar schist. The inference

Californian Metamorphic Formations.—Hershey. 241

is unavoidable that the schists are a distinct series, as a whole
much more highly metamorphosed than the Devono-Carbonif-
erous, and that at least to the extent that their alteration ex-
ceeds that of the other series, the metamorphism is not due to
the intrusion of peridotyte. ;

In the Coast Range region the serpentine areas are com-
_ monly bounded by narrow zones of contact metamorphism, the
product of which is in places a schist as thoroughly crystallized
as any part of these Klamath schists. These metamorphic
zones are nowhere of great extent and cannot be used as an
argument in support of the hypothesis that to the intrusion of
the peridotyte is due the high degree of metamorphism of the
Abrams and Salmon formations which are developed over hun-
dreds of square miles without an outcrop of serpentine. More-
over, serpentine areas five to ten miles in width adjoin the Clear
Creek greenstone and the Bragdon slates, as in the Hay Fork
section of Trinity county, without the presence of a prominent
schist belt if, indeed, there is any contact thermo-metamorphism
apparent at all.

It has been suggested that the schists represent contact
metamorphic zones due to the intrusion of a granitic batholith.
Where these batholiths rise through the hornblende schist as
near the head of the south fork of Salmon river, there is often
a narrow belt of schist next to the granite. However, this is
always merely a portion of the Abrams formation normally un-
derlying the hornblende schist and thrust up along the granite
contact as the presence of the graphitic layer proves. Large
batholiths of granite, quartz-mica-dioryte and intermediate
types occur in the areas of the Devono-Carboniferous and of
the bragdon slates and in no case are they surrounded by schist
zones such as the Abrams and Salmon formations. In fact, the
only sort of contact metamorphism that I have observed in the
Klamath region about the granitic batholiths is that the schists
and slates near the border have often been contorted by the pres-
sure of the intruded magma, and impregnated with sulphide of
iron and in general their metamorphism somewhat intensified
but not materially changed in character.

Another suggestion is that the metamorphism of the rocks
of the Klamath region is due to the action of a great magma of
fluid granitic material underlying the whole territory and deep-

242 The American Geologist. April, 230%
ly buried beneath the present surface level but exerting its in-
fluence high in the overlying strata to a degree which the com-
paratively small batholithic arms could not. This would imply
that in any given area, there was a maximum of intensity of al-
teration in the deepest portion of the strata near the granitic
mass and the degree of metamorphism decreased upward to-
ward the surface. The oldest sediments would naturally be
buried deepest and be the most altered. Afterwards elevation
and folding would bring the deeper strata to the surface and
belts of schists would come to outcrop parallel with the belts
of but slightly altered slates. As applied to the Klamath re-
gion I have the following objection to make to this hypothesis :

No fluid granite magma existed under the Klamath region
until after the Jurassic period of eruption of greenstone. Dur-
ing the deposition of the Bragdon slates or immediately after,
such a granitic magma may have formed under the region, and
when, just at the close of the Jurassic period, the entire terri-
tory was uplifted, folded, faulted and extensively fractured,
the strata subsided on this fluid magma and the batholiths and
acid dikes were formed. Now, did the metamorphism of the
schists and slates date entirely from this period, there should
be a gradual transition in the degree of alteration from the old-
est and lowest to the newest, which certainly is not the case.

I want to particularly emphasize the facts that the schist
series is about equally metamorphosed from bottom to top and
throughout its extent over hundreds of square miles, that then
occurs a break, so to say, and the Devono-Carboniferous series
although showing some variation, as a whole is altered to prac-
tically the same degree, but much less than the schists although
the two are in contact in places, while then occurs another
“break”? and the Jurassic series although showing little varia-
tion in metamorphism throughout its extent either vertically or
horizontally, as a whole is much less altered than the Devono-
Carboniferous. Taken in connection with the evidence of
unconformity between the three series the only reasonable ex-
planation is this:

After the sediments of the schist series were deposited, they
uplifted, tilted, to a certain degree metamorphosed, and then
eroded. ‘This land was depressed beneath the sea and the De-
vono-Carboniferous sediments deposited. At the close of the

rar
“Sal -

Californian Metamorphic Formations:—Hershey. 243

Paleozoic era, there occurred another uplift and tilting of the
strata. The Devono-Carboniferous formations were metamor-
phosed to nearly their present degrec, while in the earlier series
which had previously been converted into schists, there was an
intensifying of the metamorphism. In the Jurassic there came
another submergence with the deposition of the Bragdon slates,

followed by the uplift, folding, faulting and fracturing of the

strata to which the present Klamath mountains structurally are
due. During this orogenic disturbance, the Clear Creek green-
stone and Bragdon slates were well lithified, partially silicified,
and a schistose structure developed along certain limited shear
zones; in other words, the Jurassic series was slightly meta-
morphosed. At the same time there was another intensifica-
tion of the alteration of the schists and Devono-Carboniferous
series. This theory so well explains the facts observed in the
mountains that it is hardly necessary to call into play possibili-
ties which are not strong probabilities.

It is true that there are throughout the Klamath region cer-
tain narrow zones of metamorphism due to the intrusion of
various acidic and basic dikes, and they have produced even
in the Jurassic slates, schists of somewhat similar mineralogical
composition to the Klamath series, but the local character of
the former is always manifest and thereis no reason for con-
fusion. In this paper 1 am considering only the alteration that
is regional in character, affecting entire formations over many
hundred square miles. In the case of the Klamath schists this
was probably due to their having been deeply buried under
other sediments and brought under the influence of the internal
heat of the earth. The regional alteration of the Devono-
Carboniferous and Jurassic series is mainly of a dynamical!
character. Upon this is locally superimposed the thermo-met-
amorphism of the central zones.

We are now ready to consider the question of the age of the
schists. They contain no fossils and manifestly our conclusion
must be provisional and subject to modification at any time.

I feel safe in asserting that they are considerably older than
the Devono-Carboniferous series. They seem to be separated
from the latter by a non-conformity of no mean value and cer-
tainly by a great difference in degree of metamorphism. “The
relation in point of metamorphism between the Jurassic, De-

244 The American Geologist. April, 2902

vono-Carboniferous and schist series of the Klamath region is
similar to that between the Carboniferous, Cambrian and
Archean of the Appalachian region. Upon a superficial survey
the Abrams mica schist might be classed as Archzean in age.
However, I do not think it is that old, for the following rea-
sons: The Archean complexes of the eastern states are almost
invariably highly contorted and their original clastic nature to-
tally destroyed, if, indeed, any parts of them are metamor-
phosed sedimentaries. As we approach the Pacific coast, the
supposed Archzan terranes are less contorted, but the original
planes of deposition are usually not apparent. The series con-
tains granites, gneisses and schists, but never, so far as I know,
such an assemblage of formations as the mica, graphite and
hornblende schists of the Klamath region, and so perfectly pre-
serving in considerable areas their original stratified structure.

The general appearance of the series is similar to that of
the Algonkian formations in the Appalachians, lake Superior
region and the Black Hills of South Dakota. These Algon-
kian terranes frequently are but little contorted, lie at compara-
tively low angles, display evidence of their clastic nature and
original stratification, and yet are highly crystalline in charac-
ter. The same is true of the Klamath schist series.

Opposed to the idea of a Cambro-Silurian age for the
Klamath schists is the presence in different parts of California
of known Silurian and Cambrian strata much less metamorphic
in character. About the northern end of the Sierra Nevada
mountains Diller has found strata whose fossils indicate a
Silurian age.* From the description, these do not appear to be
greatly more altered than the Carboniferous of the same region
or the Devono-Carboniferous of the Klamath region. In Inyo
county, there have been found Lower Cambrian strata, also not
more metamorphic in character than the Devono-Carboniferous
of the northern part of the state.f

Yet, in other parts of the Sierra Nevada region there are
schists very similar in character to those discussed in this
paper, notably in the Big Trees area. It is usually implied
that these schists are only more altered portions of the Car-

* Descriptive text of the Lassen peak folio, U. S. Geol. Atlas.
+ Am. Jour. Sci., vol. xlix, 2395, p. 141.

t Seventeenth Annual Report, U.S. Geol. Sur., p. 536. Am. Geol, vol. xiii,
1894, p. 229.

Califorman Metamorphic Formations.—Hershey. 245

boniferous or Jurassic slates, and this is probably true of them
in large part. Some of them are referred to as possible repre-
sentatives of pre-Cambrian formations. As the Klamath re-
gion is merely a sort of outlier of the Sierra Nevada, so far as
its stratigraphical and earlier dynamical geology is concerned,
it is probable that in time a part of the Sierra Nevada schists
will be definitely separated from the Carboniferous and Jurassic
series and correlated with the Klamath schists.

On the whole, it seems impracticable to fix upon any partic-
ular part of the time between the Archzan and the the Devon-
ian as the period of deposition of the Klamath schists, but I
believe the evidence favors the earlier or Algonkian portion
rather than the Cambrian or Silurian, although I should not
like to be placed on record as correlating these schists with the
Algonkian in any other than an extremely problematical way.

Berkeley, Cal., Jan. 3, 1901.

ON THE HELDERBERGIAN FOSSILS NEAR
MONTREAL, CANADA.*

By CHARLES SCHUCHERT, Washington.

St. Helen’s Island in the St. Lawrence river, opposite Mon-
treal, and now one of the public parks and fortifications of that
city, furnishes an interesting bit of geology. At the upper ex-
tremity of the island, close to the ferry landing, is seen the
Utica shale cut by dikes of a highly altered basic rock and an
intrusive sheet of dioryte lamphrophyr (=camptonyte), and
overlain by agglomerate which covers almost the entire island.
Around the island to the southeast are occasionally found
small blocks of limestone containing Trentonian fossils, such
as Plectambonites sericeus, Strophomena incurvata, and monti-
culiporoid Bryozoa. Towards the southeastern end of the
island, along the water front, occurs the Helderbergian expos-
ure. Logan? describes the latter as follows: “There occur
two masses of dark gray fossiliferous liméstone, weathering
to a light gray; which are not magnesian. These are included
in a length of about forty yards, and are limited on the east
side by the water of the river; they have a breadth of scarcely

* Published by permission of the Secretary of the Smithsonian Institution.
+ Geology of Canada, 1863, pp. 356-358.

246 The American Geologist. April, 4000

more than ten feet, and appear to run under the dolomitic con-
glomerate [agglomerate] on the west side. They present, in
section, the appearance of two small arches of about four feet
in hight, separated from one another by a few feet of the [ag-
glomerate], and sinking under the same rock on the north and
south. * * * The dolomite [of the agglomerate] and the
limestone seem to pass into one another for a few inches, and
show no tendency to separate at the junction. * * *

“As none of this limestone comes from beneath the [ag-
glomerate], where this reposes upon the Utica fromation, it is
supposed to belong to a small disturbed lenticular portion, lying
in or under the [agglomerate]. Smaller patches of the same
limestone, a few feet in diameter, are seen in the forty yards
north of the two chief masses ; and the whole may be connected
beneath. There are other masses of similar limestone, only a
few inches in diameter, which are completely enveloped in the
conglomerate.”

The writer made two visits to this locality in August, 1900.
He found the Helderbergian limestone considerably broken.and
disturbed, with all the crevices filled up by the dolomitic paste
of the agglomerate which covers the island. The amount
of this limestone exposed is too great to warrant any assump-
tion other than that it represents an outlier im sita above the
Utica, having been subjected to seismic action shortly before
the deposition of the agglomerate. The stratification of the
limestone, as seen by the lines of fossils, is too irregular to
make out the general lay of the mass.

In the grassy slope but a few feet away from the Helder-—
bergian, there is a large block of a slightly granular siliceous
limestone involved in, and forming a part of, the agglomerate.
A number of fossils have been collected from this block and
mixed up with some from the Helderbergian. These’ speci-
mens, however, by their color and preservation, can be readily
distinguished from those of the Helderbergian limestone, and
have nothing in common with the latter. They will be men-
tioned again later on.

THE HELDERBERGIAN FAUNA.

In the Geology of Canada cited, Logan lists 9 species de-
termined by Billings. It is not necessary to reproduce this list,

Fossils Near Montreal.—Schuchert. 247

as Strophonella punctulifera and Rhipidomeila oblata correctly
indicate “the existence of the Lower Helderbergian group in
two or three small outliers in the great western basin near to
Montreal.”

Subsequently, J. T. Donald* published a list of 35 species,
among which are Orthis hipparionyx, O. oblata, O. tubulostri-
ata, Strophomena punctulifera, S. profunda, Spirifer concin-
nus, S. cyclopterus, Stricklandimia gaspensis, Pentamerus ver-
neuilit, P. galeatus, and P. pscudogaleatus. Here are forms
characterizing the Niagaran, Helderbergian, and Oriskanian
formations, an assemblage never met with in America.

In 1890, Mr. William Deeks? restudied these fossils and ex-
tended the list to 44 species. Here again appears the same re-
markable assemblage first noted by Donald. In 1896, the fos-
sils of Donald and Deeks, now in the Peter Redpath Museum,
were re-examined by Dr. Ami, who published a list of 45
species.¢ This list differs greatly from those previously given,
and is far more satisfactory, as the species included are appar-
ently of the Helderbergian or Oriskanian age, excepting a
Spirifer “very much like S. pennatus (=S. mucronatus ).”
In the writer’s resumé of the American Lower Devonic
faunas§, it is stated that one specimen of Spirifer concinnus, as
identified by Donald, “is more like S. cumberlandiae, but the
bilobed fold of the dorsal shell is a character which associates
his species with S. mucronatus Conrad, of the Hamilton.” As-
suming at that time that all the St. Helen’s Island fossils are
from the “conglomerate,’ and as Spirifer mucronatus and
“Spirifer apparently near S. granulosus Conrad” indicate a
Middle Devonic formation, that age was accepted for the “con-
glomerate” and Dr. Whiteaves was so informed. The latter, in
his presidential address before section E of the American As-
sociation for the Advancement of Science|], stated, with the
permission of the present writer, that the St. Helen’s Island
fossils “are probably the equivalent of part of the Hamilton
formation of Ontario and New York, and not of the Lower
Helderberg.” It is true that Dr. Ami was the first to notice the
Spirifer “very much like S. pennatus” but he made no correla-

* Canadian Naturalist, n. ser., ix, 1881, pp. 302-304.

+ Canadian Record of Science, iv, 1890, pp. 104-109.

~ Ann. Rept. Geol. Surv. Canada, n., ser. vii, 1896, pp. 155J-156].
§ Bull. Geol. Soc. America, 1900, p. 332.

|| The Devonian System in Canada, 1896, p. 16.

248 The American Geologist. — Ape ae

tion from it. Finally, in the paper cited above, the writer stated
—Under these circumstances, judgment is deferred as to the
age of the conglomerate on Saint Helen’s Island.”

After an examination of the fossils in the Peter Redpath
Museum and of their mode of occurrence on the island, the
evidence seemed conclusive that true Helderbergian rocks
in situ do occur in this locality, and that some of the iden-
tifications of Donald and Deeks need rectification. Mr. E.
Ardley of the Redpath Museum also showed the present writer
a small slab broken from the siliceous limestone block in the
agglomerate, which contains several well-preserved, long-
winged Spirifers, like S. pennatus. Other specimens of a Spiri-
fer from the same rock were also shown, all of which proved
that these fossils have nothing in common with the adjacent
Helderbergian fauna, but belong to one of Middle Devonic age.
The collections in the U. S. National Museum are too meager
for detailed comparison, and in this article the writer cannot
do more than correct some of the identifications of Donald and
Deeks, while pointing out the probable correlations of the Saint
Helen’s Island fossil faunas with those of New York.

* Heliolites,’ Deeks.

This seems to be based on a Striatopora. There is no
Heliolites in the locality.

“Orthis hippariony*,’ Donald and Deeks.

This identification is an error. The specimen pertains
to the same form as the “Spirifer allied to S. arenosus.”
Both these identifications are based on a Spirifer appar-
ently near S. granulosus Conrad, and S. eurytienes Owen,
of the Middle Devonic. The specimens are from the block
in the agglomerate, and have no connection with Helder-
bergian fossils.

Rhipidomella cfr. musculosa Hall?

In the U. S. National Museum collection, there is a
fragment of a large Orthis, or rather, Rhipidomella, from
the Helderbergian, which may be this species.

Rhipidomella cfr. musculosa Hall?

These specimens are usually smaller than those from

New York, otherwise they are alike for both regions.
“Strophomena profunda Donald, Strophodonta profunda”
Deeks.

Fossils Near Montreal.—Schuchert. 249

This Niagaran species was not present in the Redpath
collection last summer, nor is it listed by Dr. Ami.
Strophomena profunda must therefore be removed from
the Saint Helen’s Island Helderbergian.

Stropheodonta varistriata var. arata Hall.

The National Museum specimens of this form are poor,
but seem to agree with the New Scotland variety of the
species, as found at Becraft Mt., near Hudson, New York.

Strophonella punctulifera (Conrad).

The specimens thus labeled in the Redpath Museum
belong to an Orthis near oblata and a Stropheodonta, prob-
abaly S. varistriata var. arata. However, the species doubt-
less occurs on the island, since Dr. Ami has it in his list.

Spirifer concinnus Hall.

This is one of the common species and appears in its
typical form.

Spirifer murchisom Castelnau, early variety.

This is the commonest fossil of St. Helen’s Island,
and in the Montreal collections is usually found labeled as
S. cyclopterus. It has, however, the general expression of
a somewhat under-sized S. murchisoni from Cumberland,
Maryland. It differs from the former species in being, as
a rule, more alate, with fewer and more prominent plica-
tions. Tracing these early departures from S. cyclopterus,
the progression terminates in the Upper Oriskanian in the
typical S. murchisoni of large size, extreme inflation, an-
gulation of the plications, fold, and sinus, and great lin-
gulate extension of the ventral shell.

“Spirifer allied to arenosus’ Donald, Deeks, and Amo.

This is apparently the earliest form of the S. arenosus
type. However, it is not that species, since when small
it is much like S. concinnus, but towards maturity the fold
and sinus become plicated. Hall and Clarke figure a sim-
ilar specimen as S. concinnus (Pal. N. Y., VIII, Pt. II,
pl. 30, fig. 1). In S. arenosus of the Oriskanian, the hori-
zon for this species, the plication of the fold and sinus is
not a recently acquired character for it appears in the shell
when quite small.

“Stricklandinia gaspensis’ Donald and Deeks.

The specimen in the Redpath Museum has nothing in

common with this species. It is one of those large

The American Geologist. April, 1901

to
ut
@)

rhynchonelloids now referred to Camarothoechia (Pletha-
rhyncha), nearest to C. (P.) pleiopleura Hall. This is one
of the interesting representatives of the Saint Helen’s Isl-
and Helderbergian fauna in that it shows transition into
Oriskanian forms. Dr. Ami has likewise noted this spe-
cies.

“Pentamerus vernewlt” Donald and Deeks.

If based on the specimen thus labeled in the Redpath
Museum, this identification is an error for Spirifer con-
cimnus.

Gypidula pseudogaleata (Hall) ?

The material in the National Museum representing this
species is very imperfect, but it shows that the form is a
Gypidula without plications. Since G. pseudogaleata is
the only Helderbergian species of this type, the St. Helen’s
Island specimens are provisionally identified with Hall’s
species so characteristic of the Becraft limestone.

Rensselaeria aequiradiata Hall.

The single ventral valve of this species agrees very well
with the New York specimens of the large Helderbergian
_(Becraft) Rensselaeria.

Chonostrophia montrealensis n. sp.
Chronostrophia jerensis n. sp.

EXPLANATION OF FIGURES.

Figs. a and b, C. montrealensis, a, ventral aspect, b, surface x5.

Figs. c and d, C. jervensis, c, ventral aspect, d, surface x5. The
lines between the figures illustrate the curvature of the
valves.

Fossils Near Montreal.—Schuchert. 251

Of the first species, there are two good ventral valves which
agree well with small C. complanata as determined by Clarke.*
The Canadian specimens, however, agree best in size and form,
with an undescribed species of the Helderbergian( Becraft lime-
stone) of Port Jervis, New York, but differ in the far fainter
thread-like striz which are arranged as in Rafinesquina alter-
nata yet not so distinctly bundled as in Chonostrophia reversa
Whitfield, of the Onondaga. The Port Jervis species may be
known as C. jervensis, and is distinguished by its size and flat-
ness, but particularly by the equal, sharply elevated, somewhat
undulating, and regularly disposed striz. It generally has three
prominent, slightly diverging, cardinal spines on each side of
the ventral beak, but there are also specimens with four spines,
and others apparently with but the two lateral ones prominent-
ly developed. In C. montrealensis, there appear to be four sim-
ilar cardinal spines.

Chonostrophia begins in the New Scotland zone of the
Helderbergian in C. helderbergiae, and continues upwards as
follows: C. jervensis in the Becraft limestone, C. montrealensis
in the higher Helderbergian, C. complanata throughout the
Oriskany, C. complanata dawsomi in the Gaspé sandstone of
Quebec, and C. reversa in the Ohio Onondaga (Corniferous).

MIDDLE DEVONIC FAUNA.

It has been stated (p. 248) that in the grassy slope and
above the Helderbergian rocks in the agglomerate of Saint
Helen’s island, there is a large block of a slightly granular
siliceous limestone containing a few species of brachiopods
usually preserved as natural moulds. These fossils were
heretofore regarded as of Helderbergian age, but the species
are different and indicate a more recent formation. The Na-
tional Museum collection includes the following forms:
Dalmanella planiconvexa Hall?

There are three specimens of a Dalmanella present,
which seem to be much like the Oriskanian variety of D.
plamiconvexa. These orthoids, of the group D. testu-
dinaria, are difficult to distinguish unless the material is
good, and in the present case, therefore, only the general
aspect can be indicated.

* Memo. N. Y. State Mus., iii, no. 3, 1900, pl. 7, fig. 7.

252 The American Geologist. Ave 2aee

Spirifer macra Hall.

This is the shell referred to by Dr. Ami and the writer
as like S. pennatus=S. mucronatus. The best specimens
were collected by Mr. E. Ardley, and are now in the Red-
path Museum. The shell differs from the long-hinged
Marcellus variety of S. pennatus in having a wider ventral
hinge area and no distinct bilobation of the ventral medial
fold, characters in harmony with S. macra. It is closely
related to S. pennatus, but more directly with S. macra,
and is considerably removed from S. cumberlandiae, of the
Oriskanian. There is no shell in the Helderbergian with
which it can be compared.

Spirifer cfr. granulosus (Conrad).

Associated with S. macra, there is a more rotund spe-
cies, with high, slightly incurved ventral area, angtlar
sinus, and prominent dental plates. These are characters
associated with S. granulosus. At present none of the
specimens of this species are at hand, and no identification
can be made. However, it undoubtedly belongs to a spe-
cies in the Middle Devonic.

CONCLUSION.

The foregoing evidence shows clearly that two distinct
faunas are represented on Saint Helen’s island,—one, the Hel-
derbergian, older than the agglomerate, and another, from a
block in the agglomerate, of Middle Devonic age.

The Helderbergian fauna is apparently related with that
of New York, and belongs to the facies occurring on the west-
ern side of the Appalachian folds. The writer has collected
this fauna at Dalhousie, New Brunswick, and from the Gaspé
region, Quebec, and both are of another facies and belong to
another basin. :

The presence of Rhipidomella recalling R. musculosa; Spiri-
fer concinnus ; an early variety of S. murchisom; Spirifer n. sp.,
connecting phylogenetically S. concinnus and S. arenosus;
Camarotoechid pleiopleura; Gypidula pseudogaleata, and
Rensselacria aequiradiata, show that the Saint Helen’s Island
Helderbergian is not as old as the New Scotland zone. Spiri-
fer concinnus, and especially G. pseudogaleata and R. aequira-
diata, are characteristic Becraft zonal species. However, the

:
:

Fossils Near Montreal.—Schuchert. 253,

Oriskanian reminders, like, R. near musculosa, S. murchison,
S. near arenosus, prove that the Saint Helen’s [sland Helder-
bergian is pretty well up towards the top of the New York sec-
tion, and may represent both the Becraft and Kingston zones.

Spirifer macra and S. granulosus establish the fact that,
in the region of Montreal, there was once a formation of marine
origin later than the Helderbergian and as recent as the Onon-
daga* (Corniferous) ; further, that the agglomerate of Saint
Helen’s Island and other places about Montreal is not older
than late Middle Devonic time. Its age is probably more re-
cent, and there may be further paleontologic evidence in the
agglomerate.

REVIEW OF RECENT GEOLOGICAL
LITERATURE.

The Calcareous Concretions of Kettle Point, Lambton County, Ontario.

By Recrnatp A. Dary. (Jour. Geol., 8, 135-150.)

The concretions occur in a horizontally bedded, fissile, black,
bituminous shale of middle Devonian age. They are approximately
spherical ; one to three feet in diameter, and possess a radial crystalline
structure. An analysis of one of the concretions shows 88.42 per cent.
of calcium carbonate, only 2.99 per cent. of magnesium carbonate, and
the remainder consists of iron oxide, insoluble residue, hydrocarbons
and water. The most remarkable feature is the mechanical displace-
ment and deformation of the enclosing shales which the growth of
the concretions has involved. The pressure or “live force’ of the
growing concretions or aggregate of spherical radiating crystals has
even been sufficient to induce a true slaty cleavage in the shale at some
points. The main thesis of the author is to demonstrate that this great
centrifugal pressure is compatible with the persistence of the capillary
film investing the growing crystal or concretion and without which
its continued growth would be impossible. The explanation, which,
it would seem, must be generally accepted, is based upon the experi-
ments of Jamin leading to the conclusion that equilibrium may exist
between two unequal pressures affecting the ends of a capillary tube,
provided a column of liquid occupying the tube be interrupted by
bubbles of air. The presence of the latter excites capillary attraction
which is so strong as to take up several atmospheres of pressure ap-
plied at one end of the tube. The force so expended is represented in
the compression of the air bubbles and in changing the form of the
air menisci; surface tension is thus overcome. The movement of the
bubbles progressively decreases in the direction of the greater pres-

sure until one is reached which is not disturbed at all so long as the

254 The American Geologist. Spell, 200s
pressure remains constant. The bubbles act like so many buffers.
Any capillary tube filled with water interrupted by any insoluble gas
or liquid possessing a lower surface tension than water, will exhibit the
same phenomenon. WONG
The Granitic Rocks of the Pike’s Peak Quadrangle. By Epwarp B.

MatuHews. (Jour. Geol., 8, 214-240.)

The granites are regarded as of late Algonkian age; and four types
are recognized, differing markedly in texture but agreeing closely in
mineral and chemical composition. They are typical biotite granites,
in which hornblende rarely occurs; and a mechanical analysis of the
coarse Pike’s peak type gave: quartz 33.4 per cent; microcline, 53-35
biotite and all minerals with specific gravity above. 3.0, 10.7; and
oligoclase, 2.6; total, 100.00. The petrographic descriptions are ac-
companied by tables showing for the different types the relative abund-
ance of the sixteen component minerals, and the relative size and de-
velopment of the three essential constituents. Strangely enough, fluorite.
which occurs in three of the four types and is very marked in the Sum-
mit type, is not mentioned as-a constituent of the Cripple Creek type,
notwithstanding its prominence as a feature of the Cripple Creek ore
deposits. Another table gives the chemical composition of all but the
Cripple Creek type, in four of Hillebrand’s complete and careful anal-
yses, with determinations of seventeen constituents. When the indi-
vidual analyses and their average are reduced to molecular proportions
and compared with analyses of other granites, the Pike’s Peak gran-
ites are seen to be exceptionally rich in silica and potassium, as well
as in fluorine; and the family likeness of these types suggests their
origin ina common magma relatively rich in the elements named. AI-
though this tends to make the relative ages of the types of little mo-
ment, it may be noted that on page 223 the Pike’s Peak type is de-
scribed as clearly the oldest; while on page 228 this distinction is as-
signed to the Summit type. The reviewer's observations in this field
suggest the advisability of regarding the Pike’s Peak type as the nor-
mal granite of the batholith; the Summit type and the Cripple Creek
types as representing a once-continuous contact zone of the batholith,
in which the remnants of the Algonkian cover chiefly occur; and the
fine-grained type, which occurs only as dikes in the other types, repre-
senting residual magma intrusive in shrinkage and other cracks. Ac-
cording to this view the contact-zone types are the oldest and the fine-
grained or dike types the youngest, while the Pike’s Peak or normal
type is intermediate, having solidified after the contact zone by which
it is covered and before the dikes by which both it and the contact zone
are intersected. As might be expected, the gneissoid phase is chiefly
characteristic of the outer or border portions of the massif.

W: 0: G:
Geology of the Little Belt Mountains, Montana, with notes on the Min-
eral Deposits of the Neihart, Barker, Yogo and ether Districts. By

Water Harvey Weep. Accompanied by a Report of the Petro-

graphy of the Igneous Rocks of the District. By L V. Pirsson.

Review of Recent Geological Literature. 255

(Twentieth Annual Report U. S. Geol. Survey. Part m1 pp. 257-

581. With 42 plates and 43 figures.)

The stratigraphy represents the same general conditions that are
found in the rest of the eastern part of the Rocky mountain area of this
state. One feature of especial importance is shown in the Little Beli
area, namely, the overlap of the Cambrian beds from the Algonkian
in the south to the Archean in the north.

The present structure and altitude of the Little Belt mountains are
due to an uplift and folding of the range as a whole, accompanied by
a contemporaneous intrusion of large igneous masses producing minor
folding and faulting. The principal peaks are igneous and present a va-
riety of types. Sheets, laccoliths, and bysmaliths are found, all three
ferms grading into one another. Mr. Weed discusses at some length
the origin of such intrusions, concluding that in this region the form
is a function of viscosity of lava, of resistance of overlying beds, and
of the ascensive force.

* At least two periods of igneous activity preceded the uplift of the
range. The uplift was accompanied by a third period of activity,
which was immediately followed by the formation of fissure veins in
which the ore deposits occur. Inferentially these ores are believed to be
post-cretaceous. Secondary enrichment has played an unusually im-
portant part in the development of some of the ores.

Professor Pirsson’s report embraces a detailed description of the
petrography of the region, and a discussion of analysis and of esti-
mated mineralogical composition. He classifies the igneous rocks into
four groups:

a. Granular nonpborphyritic rocks, of plutonic origin, including
syenites, monzonites, diorites and shonkinites. Yogo peak shows, as
part of a single geologic mass, monzonite grading into syenites on the
one hand and into shonkinite on the other. This connection is interest-
ing in that it exhibits in the field the grouping which Brégger has sug-
gested on theoretic grounds. Monzonite is not uncommon in the west,
appearing in company with either more feldspar or more basic types,
and represents the portion of mean composition in a differentiated
complex.

b. Acid feldspathic porphyries, the predominant rock of the lac-
coliths and of a considerable portion of the dikes and sheets. These
rocks present many transitions, the transitional masses being often of
more importance locally than the commonly known types.

c. Lamprophyres, occurring in small dikes and sheets, and includ-
ing minettes, vogesites, and analcite basalts. Variolitic facies, shown
by some of the minettes of this region, is described as of a spherulitic
nature. In this interpretation the author agrees with that of Pohlmann
for the variolitic facies of the kersantites of Thuringia, and differs
from the general explanation of the structure offered by Rosenbusch
in his text-book. These minettes afford no evidence of the action of
absorbed aqueous vapors, as described by Cross and by Iddings for
spherulites in acid glassy rocks. ;

256 The American Geologist. April, 1901

d. Effusive rocks, consisting of two flows of basalt.

The average composition of all the rocks described is calculated
to be that of an acid syenite approaching a monzonite in character. The
rocks of the laccoliths here, as nearly everywhere in the Rocky moun-
tain region, are usually porphyritic and acid. They are typical exam-
ples of Rosenbusch’s granitic porphyritic dike rocks, which are here
typically laccolithic. The phenocysts appear to have been formed
where they now are, and in no case to have been brought up from
greater depths. No differentiation has been noted in the laccoliths.
Yogo peak and the porphyries east of it are examples of differentiation
in place, the centre of the mass being acid and the periphery basic. The
tendency is here shown for acid rocks to be porphyritic, and basic rocks
under the same conditions, granular. Chemical composition, not depth
of intrusion, is seen to be the determining factor of granularity.

Numerous small syenite-aplite dikes cut the Yogo mass. They rep-
resent the acid residuum forced up into the fracture planes of the upper
and previously solidified rock.

The report closes with a discussion of magmas by graphic methods,
and of absorption of sediments by magmas. The chemical composi-
tions of the Yogo peak rocks are shown to bear a mathematical relation
to one another, which points to a common origin.

This area presents no facts in favor of the view that large amounts
of sediments may be absorbed by magmas and produce alterations in
composition of igneous rocks. 15 91-40:
Notes on the Limestones and General Geology of the Fiji Islands, with

special reference to the Taw Group. Based upon surveys made for

Alexander Agassiz. By E. C. Anprews. (Bull. Mus. Comp. Zool.

of Harvard College. Geol. Survey, vol. v, No. 1. Pp. 1-46; with

4o plates. )

This paper represents a more careful examination of some of the
problems suggested to Mr. Agassiz in his exploration of Fiji in the
winter of 1897-8. Further results brought in by the W. S. F. C. S.
“Albatros,” yet remain to be worked up. Mr. Agassiz expects shortly
to publish a final report upon the islands.

The present paper consists of careful descriptions of the different
beds accompanied by excellent illustrations and maps. The islands are
a group of atolls which in Tertiary, and again in recent time, were
subject to volcanic activity. The limestones are indurated in some lo-
calities and soapstone is found. There is a decided excess of igneous
over calcareous rock. Te Ea:

Contributions to the Geology of Maine. By H. S. WixtaMs and H. E.

Grecory. (Bul. U. S. G. S. No. 165.)

A report upon the fauna of Maine was greatly to be desired for pur-
poses of comparison between the typical forms of New York and of
Canada, and also as a basis of correlation between American and Eu-
ropean Paleozoic phases. This paper deals with sedimentary areas in
Somerset and Aroostook counties, and with the Aroostook volcanic
area.

Review of Recent Geological Literature. 257

Part 1, by Dr. Williams, deals with the Paleozoic fauna. He de-
scribes the fossils from various formations, giving good illustrations,
but reserves more detailed descriptions for future publication. In this
paper he discusses especially phylogeny and variation. The boundary
between Silurian and Devonian was first described in the Welsh series
in which transition was from calcareous sediments with a marine
fauna to sandstone with brackish fauna. Dr. Williams now deter-
mines this boundary for America. The Lower Helderberg in the in-
terior is closely related to the succeeding fauna, because there was no
radical disturbance in the marine conditions. It is the Oriskany fauna
that shows evidences of a disturbance which ended in uplifting large
areas of marine surface; and this formation is to be correlated with
the Gedennian of the Rhenish provinces, and with the base of the Old
Red sandstone of Great Britain. Thus the Lower Helderberg is to be
located positively as Silurian, in spite of the Devonian relationships of
its New York fauna. The Gaspé and Square Lake limestones of
Maine both contained evidence of New York Lower Helderberg fauna,
and both occur below the Devonian boundary line.

It is to be regretted that Dr. Williams does not institute a compari-
son between the Upper Helderberg fauna and that of the Ludlow beds
of England, which represent the typical Upper Silurian as defined by
Murchison and Sedgwick. Since the Siluro-Devonian boundary may
now be regarded as established for both countries, a comparison be-
tween the faunas of equivalent beds would be of interest.

Part 11, by Dr. Gregory, deals with the volcanics and clastics of the
Aroostook country. Northeastern Maine is essentially a region of
sedimentary rocks, yet such igneous rocks as there are, present a
number of well defined types, and considerable variation in character.
Dr. Gregory discusses fully the general nature, field relations, petro
graphy, and chemical composition of the volcanics. The clastics are
classified on a petrographic basis and mapped from this standpoint,
their stratigraphic relationships being left until further evidence is ob-
tained. The structure and history of the region as a whole are not
touched upon.

Part 111 consists of a list of localities where outcrops were found,
and is a most useful addition to a work of this sort. ie SO:

Geology in its Relations to Topography. By T. C. BRANNER. With
Discussion and Correspondence, Trans. Anver. Soc. of Civil Engi-
neers, XXXIX., pp. 54-05.

Complaints are often heard from geologists of the inaccuracy of
maps. Mr. Branner strikes at the root of this matter in showing the
necessity of geological knowledge for a successful topographer. There
is at present no physiographical text book adapted to the needs of en-
gineers and it is to be hoped that some expert in geology or geography
will soon meet this demand. Mr. Branner’s paper contains'a short ac-
count of some of the simplest physiographic features and supplies in
untechnical language valuable information in regard to a few of the
problems which confront engineers. I. H. O.

258 The American Geologist. April, 100%:

Researches on the Visual Organs of the Trilobites. By G. Linpstrom.
Six Plates. (Kongl. Svenska Vetenskaps Akad. Handl., Bd. 34,
No. 8.)

This is a most important contribution to the biology of the trilobites.
First, because it challenges proof of the presence of eyes in many spe-
cies that are supposed to have had visual organs, denying that the struc-
tures that have been taken as such are eyes. And secondly because it
announces the discovery of true eyes on the hypostone of many spe-
cies.

Lindstrom claims that the assumption that because a trilobite had
an “eye lobe” it therefore had eyes is quite without foundation, for he
teaches that this “eye lobe” is due to the impact of the free-cheek at
this point with the inner cheek, and he states that in a number of spe-
cies which he has examined there is no space for an eye between the
two pieces of the head shield which there come in contact. The oldest
genera with true eyes on the cephalic shield, which he recognizes, are
such of the Upper Cambrian, as Petiera Sphcerophthalmus and Ctino-
pyge. In the Ordovician, Silurian and Devonian, the genera in which
true eyes exist on the head shield, are multiplied. There is an interest-
ing discussion on the origin of the facial suture with applications in
Olenellus, Paradoxides, Liostraeus, Solmopleura, etc. He does not rec-
ognize the presence of eyes or a suture in Agnostus.

Most interesting to paleontologists is the announcement that the tu-
bercles or, as Mr. Lindstr6m calls them, the ‘“‘macule” in the anterior
furrow of the hypostome, as seen in many species, had ocular proper-
ties. Not only by the thinness of the skin over these spots, but by the
actual presence of lenses in them, has he proved that the macule in
many species possess this office. This discovery of this condition of
the maculze was made by his draftsman and assistant, Herr G. Lilje-
vall. Many trilobites, it would thus appear, had eyes below as well
as on the upper side of the headshield.

This important memoir is fully illustrated with six admirable plates
and several text figures; in the former the admirable handiwork of
Herr Liljevall is patent. :

That this work is founded on abundant material may be assumed
when it is stated the hypostomes of thirty-six species of trilobites have
been sectioned for investigation. These range from the Cambrian to
the Devonian.

Herr Lindstr6m considers that the trilobite eye is best represented
in that of Apus and the Isopod. GF Me.

CORRESPONDENCE.

ON THE AGE OF CERTAIN GRANITES IN THE KLAMATH MOUNTAINS.
[Abstract.] Small batholyths and dikes of granite, quartz-mica-dioryte
and intermediate types are shown to occur at various places in the
Klamath region, but in areas quite subordinate in extent to those of
the metamorphic rocks in which they have been intruded. The same

Correspondence. 259

region contains extensive areas of serpentine, and instances are given
of the granitic rocks having been intruded into the serpentine to prove
that the granites are newer, in accordance with the determined relations
of these rock types in the Sierra Nevada region, and the reverse of the
supposed relation between the granite and serpentine of the Coast
ranges.

The black slates of the Klamath region are divided into two dis-

_ tinct series, referred to as the lower slates and the upper slates. The

former are considered Devono-Carboniferous in age, being in part
equivalent to the Calaveras formation. The latter are correlated, on the
evidence of their lithology and their structural relations, to the lower
slates and to a certain extrusive greenstone formation of the Sierra
Nevada region, with the Mariposa formation of late Jurassic age. The
intrusion of granite occurred later than the deposition of these upper
slates. Also it is shown that the granites are much older than the
Chico formation resting on them as they must have suffered much
erosion prior to the Chico epoch.

It is finally concluded that the weight of evidence places the gran-
itic intrusion just about at the close of the Jurassic period. The effect
of the agreement is to show that there is a sound basis for the inference
heretofore entertained that the Klamath mountains belong rather to
the same system as the Sierra Nevada instead of the Coast ranges, and
may be considered a sort of out-lier to the former.

Berkeley, Cal. Oscar H. HersHey.

A Nationa Museum For CANADA. The growth and progress of the
work done by the staff of the Geological survey of Canada have reached
that point in the history of this classic state institution, which dates
from 1842, when the headquarters and museum on Sussex street have
become not only over-crowded and limited in accommodation, but also
positively unsafe. The mass of specimens displayed has long ago
reached its crisis, and special orders from the Honorable the Minister
of Public Works have compelled the Museum proper to be lighteneri
as far as possible. Besides this, a large series of wooden posts—in
the neighborhood of sixty—have been placed at proper intervals on threz
floors to act as so many props and supports for the collections of ores,
minerals and rocks of economic value, etc., in the Dominion of Can-
ada. The building now occupied by the Staff and Museum is totally
inadequate for the requirements of the times. It is practically impos-
sible and unsafe to exhibit any discovery made or record the numerous
finds and donations received in a tangible or accessible manner. There
are thousands of specimens in the possession of the Geological Depart-
ment which are rendered quite inaccessible, owing to lack of space, and
an effort is now being put forth towards obtaining a suitable and fire-
proof building in which the products of the earth in Canada, whether
as regards its mines, forests, and waters, will be exhibited to advantage.

In looking over the Report of the U. S. National Museum, drawn
up by the Acting Assistant Secretary, the Hon. C. D. Walcott, the vari-
ous divisions and subdivisions of work are given in such a manner as to

260 The American Geologist. April, 200%

indicate clearly the line in which it is confidently expected that, at no
distant date, the politicians of Canada will see to it that a National
Museum will be established at Ottawa, properly equipped, manned and
maintained.

It is an urgent necessity that a Central Bureau of scientific, in other
words, exact information exist, where not only reports upon all kinds
of subjects can be obtained from specialists, but where a record is kept
of information gathered and specimens obtained during explorations,
researches, and studies, in connection with the natural resources of half
a continent.

The incalculable value of the National Museum to the United States
has been recognized by Congress, and it is hoped that Canadian states-
men will see-that before long a suitable office and museum buildings
be erected, and a thoroughly equipped and efficient staff established, so
that the wonderful natural resources of Canada may be exhibited to
advantage and carefully published for the information of all.

H: M. Amt.

Geological Survey of Canada, Ottawa, Feb., 1901.

MONTHLY AUTHOR’S CATALOGUE

OF AMERICAN GEOLOGICAL LITERATURE
ARRANGED ALPHABETICALLY,

Adams, Frank D.

Memoir of Sir J. William Dawson. (Bull. Geol. Soc. Am., vol. 11,
1890. )

Adams, Frank D.

Nodular Granite from Pine lake, Ontario. (Bull. Geol. Soc. Am,
VOL. 9, Dp. 163-172) pl ru)

Adams, Frank D.

On the probable occurrence of a large area of Nephaline-bearing
rocks on the northeast coast of lake Superior. (Jour. Geol., vol 8, No.
4, May-June, 1900.)

Adams, Frank D. and J. T. Nicolson.

An experimental investigation into the flow of marble. (Proc.
Royal Soc., vol. 67.)

Ami, H. M.

“Stratigraphical Note.” Being a summary of preliminary work on
the Silurian formations of Antigonish county, Nova Scotia. (Science,
new series, vol. 13, No. 323, pp. 394-395, March 8, rgor.)

Blake, W. P.

Some Salient Features in the Geology of Arizona, with Evidences
of shallow seas in Paleozoic time. (Am. Geol., vol. 27, pp. 160-167,
March, 1901.)

Claypole, E. W.

Notes on Petroleum in California. (Am. Geol., vol. 27, pp. 150-
160, March 1901.)

Author's Catalogue. 261

Cummings, E. R.
Orthotetes Minutus, n. sp., from the Salem limestone of Harrods-
burg, Ind. (Am. Geol., vol. 27, pp. 147-150, pl. 15. March, 1901.)

Cushing, H. P.

Preliminary Report on the Geology of Franklin County, N. Y..,
part 3. Map and 8 plates. (From the 18th report of the State Geolo-
gist, 1900.)

Davis, W. H.

An Excursion in Bosnia, Hercegovinia, and Dalmatia. (Bull.
Geog. Soc., Philadelphia, vol. 3, pl. 4, February, roor.)

Dawson, Geo. M.

Physical History of the Rocky Mountain Region in Canada. (Sci.,
new series, vol. 13, No. 324, pp. 401-407, March 15, gor.)
Gordon, C. H.

Geological report on Sanilac county, Michigan, accompanied by 5
plates, 2 figures and one colored map. (Geol. Sur. Mich., vol. 7, part
3, PP. 34-)

Gould, Chas. N.

Notes on the Geology of parts of the Seminole, Creek, Cherokee and
Osage Nations. (Am. Jour. Sci., vol. 2, p. 185, March, Igor.)

Gratacap, L. P.

Note on an interesting specimen of Calcite from Joplin, Mo. (Bull.
Am. Mus. Nat. Hist., vol. 13, 1900, p. 95, pl. 6.)
Gregory, J. W.

The plan of the earth and its causes. (II.) (Am. Geol., vol. 27,
pp. 134-147, March, 1901.)
Hatcher, J. B.

The lake systems of southern Patagonia. (Am. Geol., vol. 27, pp.
167-174, pl. 17, March, 1901.)
Heilprin, Angelo.

The shrinkage of lake Nicaragua. (Bull. Geog. Soc. Philadelphia,
VOlseas Jatl., 1001, pp. I-12.)
Heilprin, Angelo.

Volcanic phenomena of Hawaii. (Bull. Geol. Soc. Am., vol. 12,
pp. 45-56, pls. 2-5.)
Hitchcock, C. H.

The water supply of lake Nicaragua. (Bull. Geographical Soc.
Philadelphia, vol. 3, Jan., 1901, pp. 12-20.)
Hollick, Arthur.

A reconnoissance of the Elizabeth Islands. (Annals New York
Acad. Sci.’s vol. 13, No. 5, pp. 387-418, pls. 8-15.)
Hollick, Arthur.

The relation between forestry and geology in New Jersey. (Ann.
Rep. State Geologist of N. J., 1899.)
Hollick, Arthur.

Fossil plants from Louisiana. (Contributions Geol. Dept., Col.
University, vol. 9, No. 67.)

262 The American Geologist. Ape ome

Komp, Jd. Fa
The re-calculation of the chemical analyses of rocks. (School of
Mines Quarterly, No. 1, vol. 22.)

Kemp, J. F.
Pre-Cambrian sediments in the Adirondacks. (Annual address of
Pres. Sec. E. Am. Association for the Adv. Sci., vol. 49, 1900.)

Lane, Alfred C.

Geological report on Huron county, Michigan, accompanied by II
plates and 12 figures including two colored maps. (Geol. Sur. Miclh..,

vol. 7, part 2, pp. 330.)
McCallie, S. W.

Preliminary report on a part of Iron Ores of Georgia, Polk, Bar-
ton and Floyd counties. (Bull. No. 10-A, Geol. Sur. of Georgia, pp.
190, map and 6 plates.)

McCallie, S. W.

Some notes on the Trap Dikes of Georgia. (Am. Geol., vol. 27,
pp. 133-134, pls 12-14, March, 1901.)

Nicolson, John T. and Frank D. Adams.

An experimental investigation into the flow of marble. (Proce.
Royal Soc., vol. 67.)

Prosser, Chas. S.

Sections of the formations along the northern end of the Held-
erberg plateau. (From the 18th annual report of the State Geologist
ot New York.)

Prosser, Chas. S.

Names for the formations of the Ohio Coal measures. (Am. Jour.
Sci., vol. 11, p. 191, Mar., 1901.)

Sherzer, W. H.

Geological report on Monroe Co., Michigan, accompanied by 17
plates and 8 figures including 3 colored maps. (Geol. Sur. Mich., vol. 7

part I, pp. 240.)
White, Theodore G.

Report on the relations of the Ordovician and Eo-Silurian rocks
iu portions of Herkimer, Oneida and Lewis counties. (Contributions
from Geolog. Dept. Col. Univ., vol. 9, No. 66.)

White, Theodore G.

Upper Ordovician faunas in Lake Champlain valley. (Bull. Geol.
Soc. of America, vol. 10, pp. 452-462.)
Whitfield, R. P.

Observations on and descriptions of Arctic fossils. (Bull. Am.
Mus. Nat. Hist., vol. 13, 1900, No. 19, plates 1 and 2.)
Whitfield, R. P.

Description of a new Crinoid from Indiana. (Bull. Am. Mus. Nat.
Hist., vol. 13, 1900, pl. 3, p. 23.)

Winchell, N. H.

Glacial lakes of Minnesota. (Bull. Geolog. Soc. Am., vol. 12, pp.
1c9-128, pl. 12.)

Personal and Scientific News. 263
PERSONAL AND SCIENTIFIC NEWS.

Mr. H. E. Grecory has been promoted to be assistant pro-
fessor of physical geography at Yale University.

Dr. W. B. Scort, professor of geology in Princeton Uni-
versity, expects to leave for South America, especially for Pat-
agonia, in May.

‘- Mr. E. J. Garwoop has been appointed to the Yates Gold-
smid chair of geology and mineralogy at University College,

_London, to succeed Prof. T. G. Barney.

GEoLocicaL Society OF WASHINGTON. At the meeting of
March 13th, the following was the program: “The Soil Survey
of Cecil county, Maryland,” by C. W. Dorsey ; * ‘Discussion of
geologic units : formation, stage and age,” by Bailey Willis, H.
S. Williams and others.

GEOLOGICAL SocIETY oF WASHINGTON. At the meeting of
March 27th the program consisted of the conclusion of the dis-
exussion of geological units, by Messrs. H. S. Williams, C. R.
Van Hise, T. C. Chamberlain and others.

Mr. JAMES BENNIE, formerly of the Geological Survey of
Scotland, died on January 28th. He contributed papers to the
Transactions of the Geological Societies of Edinburgh and
Glasgow, and two years ago was awarded the Murchison fund
by the Geological Society ‘of London.

GEOLOGICAL SURVEY OF GREAT BRITAIN AND IRELAND. Mr.
J. J. H. TEALL, president of of the Geological Society of Lon-
don, has been appointed director to succeed Sir Archibalc
Geikie, who retired on February 28th after 46 years of service
on the Survey.

ScHoot SCIENCE is the title of a new journal devoted to
science teaching in secondary schools. It is edited by C. E.
Linebarger and published at Unity building, Chicago. There
is a corps of associate editors, among whom are E. C. Case
(Geology) and Wm. H. Snyder (Geography ).

Tuomas BENTON Brooks died on Nov. 22, 1900. Major
Brooks was a well-known worker in American geology, and the
work for which he will be most frequently praised is that which
he did in the iron districts south of lake Superior. In
Science for March 22nd Mr. Bailey Willis gives a sketch of
Major Brooks.

De OsERT BELL; MM. Dee eas. FG. S. has
been appointed director of the Geological Survey of Canada,
vice G. M. Dawson, deceased. It is understood that Dr. Bell
will soon be officially gazetted as “director” of the Canadian

264 The American Geologist. Batis

Survey, on which staff he has been engaged for upwards of
forty years.

On Saturday, March, 2d, 1901, at the hour of 6:05 p. M., Dr.
George M. Dawson, C. M. G., F. R. S., F. G. S., ete, member
of the Geological Survey of Canada since 1875, and its able and
distinguished director since 1895, died of capillary bronchitis,
resulting from a slight cold. He had been attending to his of-
ficial duties with the usual vigour and enthusiasm up to a late
hour Thursday, Feb. 28th, only one day of twenty-four hours
intervening before death came. A notice of his life and works
will appear later.

THE CERRILLOS ANTHRACITE MINES.—We have, or are sup-
posed to have, so little anthracitecoal in the West that a veritable
anthracite coal mine is a novelty of especial interest. Such we
heard of being near Cerrillos Station in New Mexico, and ina
recent visit to that country we stopped off to examine it. We
were surprised to find not only a well and deeply developed
mine, but a coal village around the works of many substantial
houses and numbering some 500 to 800 inhabitants, with an
extensive plant and a large coal breaker of thoroughly eastern
or Pennsylvania pattern.

The Cerrillos mountains are a small group of hills some
50 miles north of Albuquerque city, New Mexico. They are
formed of a central core of eruptive porphyritic rock surround-
ed by a series of uptilted sandstones of the Laramie Cretaceous
coal-bearing series. Into these strata many dikes and in-
trusive sheets of porphyryte have been intruded, emanating
from the parent core. The heat from these eruptive sheets,
when they have come near enough to the coal, has metamor-
phosed the coal into anthracite. Coal beds not so influenced in
the same region remain unchanged as bituminous coal, conse-
quently there are two classes of coal worked near one another.
One a four foot six inches seam of bituminous coal and another.
some 50 to 75 feet below, of three feet six inches to four feet
of puiiracne: overlain by a thick intrusive sheet of eruptive
porphyrytes—(Mines and Minerals.)

THe PALAEONTOGRAPHICAL SOCIETY announces that mon-
ographs of the following groups of fossils are in course of
preparation, and will be published by the Society : the Carbon-
iferous Lepidodendra, by Dr. D. H. Scott; the Cycadez, by
Mr. A. C. Seward; the Graptolites, by Prof. Lapworth, assist-
ed by Miss Elles and Miss Wood; the Fishes of the Chalk, by
Dr. A. S. Woodward; the Reptilia of the Oxford Clay, by Dr.
C. W. Andrews; and the Cave Hveena, by Mr. S. H. Reynolds.
The volume issued by the Society for 1900 contains the Cre-
taceous Lamellibranchs, by Mr. H. Woods; the Carboniferous
Lamellibranchs, by Dr. W. Hind: and the Carboniferous
Cephalopods of Ireland, by Dr. A. H. Ford. ( Nature.)

THE AMERICAN GEOLOGIST, VOL XXVII. PLATE XXV.

Lip -EHE

AMERI@A&N. GEOLOGIST.

me VOb. AAVIE | MAY, 1Igol. No. 5.

BRIEF BIOGRAPHICAL SKETCH OF
ELKANAH BILLINGS.
Palaeontologist to the Geological Survey of Canada from 1856 to 1876.

By HENRY M. AMI, Ottawa, Canada.

The late Elkanah Billings, who for twenty years was pal-
eontologist to the Geological Survey of Canada, and was the
founder of the. Canadian Naturalist and Geologist, was born
in the township of Gloucester, along the right bank of the Rid-
eau river in the old, and now demolished Billings homestead
situated a few yards below the present bridge which spans
that river at the little village of Billings’ Bridge. He was the
second son of Mr. Bradish Billings, whose ancestors came
from England, while those on his mother’s side came from
Wales. His grandfather was a Brockville physician, Dr. El-
kanah Billings, after whom the subject of this sketch was
named. Both his parents, however, were born in the United
States, his father in Massachusetts, and his mother in New
York state.

From Dr. Whiteaves’ obituary notice of Elkanah Billings
the following extracts are made:

“Elkanah Billings, our esteemed associate for so many
years, was born at the family homestead on the 5th of May,
1820. His first teacher was a governess (Miss Burrit), his
next a family tutor named Maitland, and he afterwards went
to three small schools in the neighborhood, kept respectively
by Messrs. Colquhoun, Collins and Fairfield. In 1832 the
youth was placed at Rev. D. Turner’s school in Bytown; as a
day pupil and after four years’ interval, during which he re-
mained at home on the farm, his parents sent him, in 1837, to

266 The American Geologist. May,1901. .

the St. Lawrence Academy at Potsdam, in the state of New
York, of which the Rev. Asa Brainard was principal.

On leaving this institution Mr. Billings entered the Law
Society of Upper Canada as a student in 1839, and was ar-
ticled to Mr. James McIntosh, a barrister in Bytown. Mr. Mc-
Intosh died in the same year and was succeeded by Mr. Au-
gustus Keefer, with whom Mr. Billings remained for nearly
four years; and it appears that he was for a short time also in
the office of the late Mr. George Byron Lyon Fellowes in the
same town. In 1843 he went to Toronto, and studied for a
twelve-month longer with the legal firm of Baldwin & Wilson,
and was admitted to practice as an attorney in the fall of
1844. Soon after this he returned to Bytown and entered into
partnership with Mr. Christopher Armstrong, who was then
one of the judges of the county court, but a law having been
passed prohibiting judges from pleading, the partnership was
dissolved after having lasted only six months.”

In 1845 Mr. Billings married a Toronto lady, a sister of
the Hon. Judge Adam Wilson. Between 1845 and 1848, he
practiced law in Bytown, having been called to the bar in
1845; in 1849, however, he removed to Renfrew where he
practiced his profession until June, 1852, when he returned to
Bytown, where most of his time was engaged in journalistic
and scientific pursuits. He occupied the editorial chair of
The Citizen from the fall of 1852 until late in 1855. Many
of Mr. Billings’ leading articles in the Citizen of those days
comprised popular disquisitions on geological topics and
natural history subjects, which served to indicate the trend of
thought of the man whose subsequent life led him into in-
quiries of the highest scientific type, whose writings are now
held in highest esteem and well known the whole scientific
world over. It was during these years of his residence in By-
town that he began the systematic study of the fossiliferous
rocks which are so extensively developed along the banks of
the Ottawa river in the vicinity of our city.

Probably at first entered upon more as a pastime and re-
laxation from his journalistic duties these researches cul-
minated in his final adoption of geological studies, especially
in the department of fossil organic remains, for the remain-
der of his life.

Biographical Sketch of Elkanah Billings—Ami. 267

The magnificent collections of Crinoidea, Cystoidea and
Asteroidea from the Trenton limestone of Ottawa, that are
now exhibited in the museum of the Geological Survey of
Canada, testify to his remarkable success and energies in these
researches, for it must be remarked that these organisms are
exceedingly rare and great diligence as well as patience must

be exercised if satisfactory results are to be obtained. -

Early in 1856 Mr. Billings issued the first number of the
Canadian Naturalist of which, and the succeeding numbers
of the first volume, he was practically the sole contributor.
The production of this number marks an epoch in the his-
tory of the progress of scientific research and discussion in
Canada. The articles contained in the first volume of the
Canadian Naturalist and Geologist at once stamp Mr. Bill-
ings as a master in description both of fossil organic remains
and of recent natural history objects.

Previous to the issue of this magazine, Mr. Billings had
been brought into direct communication with Sir William
Logan, then director of the Geological Survey of Canada, and
it was not long, yea, but few months elapsed, until the latter
with his usual clearsightedness engaged the services of Mr.
Billings, his friend, as paleontologist to the Geological Sur-
vey of Canada. It was in August, 1856, that Mr. Billings en-
tered upon his duties as government paleontologist and, un-
til his death, which took place June 14, 1876, a period of near-
ly twenty years elapsed in which he worked ceaselessly in the
domain of paleontology, and in assisting his chief and direc-
tor in assigning geological outcrops to the various geological
horizons of eastern Canada, involving numerous and difficult
problems which made it a task of no mean importance.

His first geological paper was published in April, 1854,
and was entitled “On Some New Genera and Species of Cys-
tidea from the Trenton Limestone.’ It was published in the
Canadian Journal, Toronto, page 215. On removing to Mon-
treal in 1856, Mr. Billings removed also the headquarters of
his magazine. The Canadian Naturalist and Geologist,
from that date on was published in Montreal under the same
designation and under the name of Canadian Naturalist and
QO. J. So., until 1883, when it was superceded by the Cana-
dian Record of Science, and became the recognized official

268 The American Geologist. Max, AEVE

organ of the Natural History Society of Montreal. Of this
society he was regularly elected a vice president for 14 years,
having declined the office of president, proffered to him on.
many occasions.

In 1858 Mr. Billings made a visit to Europe, where he came
in contact with leading geologists of the time and examined
various collections in geology in Great Britain. These he
studied most zealously and made a comparison of the Silurian
(including both the lower and upper Silurian of Murchison)
and Devonian fossils of western Europe, with those of Cana-
da, and arrived at the conclusion that there were but few
species identical with those of Canada. In April, 1858, when
in London, he was elected a fellow of the Geological Society
of London; Sir Roderick Murchison, Professor A. Ramsay
and Professor T. H. Huxley, having nominated him. He
visited Paris where he met a number of distinguished men,
amongst others the great Bohemian paleontologist, the Abbe
Joachim Barrande, with whom and in conjunction with Sir
William Logan, a most interesting discussion arose regarding
the age of several rock formations occurring in the province
of Quebec, to which Sir William Logan gave the name “Que-
bec Group”’—a controversy which included many difficult
problems of which the “Taconic Question” was a conspicuous
factor. :

The term “Quebec Group” will invariably be associated
with the excellent work performed by Sir William Logan and
Mr. E. Billings.

In 1854, two years before his appointment on the Geologi-
cal Survey staff, Mr. Billings accompanied Mr. James Rich-
ardson in an examination of the fossiliferous rocks of Point
Levis, Que.; in the following year he also accompanied the
same field geologist in his explorations at Point Levis, Que.,
and Thetford, in the township of Bosanquet, County of
Lambton, Ontario.

Of Mr. Billings’ work prior to 1863, Sir William Logan
gives the following succinct account on page 7 of the “Pre-
face” in his “Geology of Canada,” published in 1863:

“Mr. Billings was appointed paleontologist to the survey
in 1856 and since then his unremitting attention has been de-
voted to the study of the palaeozoic fossils of Canada, of

Biographical Sketch of Elkanah Billings—Ami. 269

which very considerable collections have been made in our
various explorations.

“Of these fossils he has described in the publications of the
survey and in the scientific journals of the province; 526 spe-
cies, of which 395 are Lower Silurian, 67 Middle and Upper
Silurian, and 64 Devonian.

_ “Fe has thus greatly facilitated the means of determining
with precision the limits and distribution of our geological
formations, and of the economic substances which they con-
tain. In order to insure uniformity in the paleontological part
of this work, all the palaeozoic fossils mentioned in it have
been submitted to the inspection of Mr. Billings, and the spe-
cies are therefore all given on his authority. Of the described
Lower Silurian species found in Canada, not including those
of the Quebec group, he has prepared a catalogue, showing
their vertical distribution, and referring to the publications in
which the descriptions and figures will be found. This cata-
logue has been introduced into the appendix to this volume.”

Then after a brief sketch of the early studies made by him-
self in the “Quebec Group” of rocks, Sir William points out
what part Billings played in the unravelling of that interesting
succession of palaeozoic sediment. He goes on to say: “But
the discovery in May, 1860, of the Point Levis fossils at once
enabled Mr. Billings to conclude that the rocks of the Que-
bec group must be placed near the base of the second fauna
of Barrande or about the horizon of the Calciferous and
Chazy formation. This opinion, our subsequent investiga-
tions in the neighborhood of Lake Champlain, and of the
Strait of Belle Isle, have completely borne out, and there now
remains little doubt that the attitude of the rocks in question in
the vicinity of Quebec is due to a great overlap, which runs
from southwest to northeast through the whole length of the
eastern part of the province, and extends in both directions far
beyond it.”

The above serves to show clearly the remarkable work
done by Billings in that most difficult field east of the great
Champlain, St. Lawrence or Appalachian fault.

His critical eye detected differences where they had not
been seen and by his knowledge the vertical range of fossil re-
mains was firmly established.

27.0 The American Geologist. May, Eee

Notwithstanding all the attacks that have been made upon
the validity of the term “Quebec Group,” and the discussions
on its significance, it is as truly a natural group or division in
the succession of paleozoic sediments in eastern Canada today
as it was in the 50’s and 60’s, and the chapters devoted to this
most important study in the “Geology of Canada” for 1863,
are replete with wisdom and forethought.

On several occasions Mr. Billings made extensive collec-
tions in the Silurian as well as in the Devonian formations of
Ontario and in the vicinity of Montreal, as can be seen from
the collections now in the geological department, but the bulk
of his time was devoted to the determination of geological
horizons for mapping purposes and the description of new
genera and species brought in to the department by the va-
rious field-geologists. Of genera new to science, Mr. Bill-
ings described no less than 61 and in all described 1,065 new
species of fossil organic remains from various horizons in the
paleozoic of Canada. He also contributed many papers on
natural historv and zoology.

He did much in assisting Sir William Logan to establish
and build up the geological museum, for, besides the large
number of new species which he described, he identified as
many more, from Canada, with forms previously described
by Conrad, Hall, Emmons, Vanuxem and Sowerby, and other
paleontologists of America and Europe.

His writings indicate a clear and precise mind, coupled
with a rare judgment; they are couched in a phraseology sim-
ple but to the point. He published upwards of 170 distinct pa-
pers, memoirs or reports, many of which are now very diff-
cult to obtain or entirely out of print. The bulk of his writ-
ings are embodied in the reports of the Geological Survey of
Canada, comprising the figures and descriptions of “Canadian
Fossil Organic Remains,” or Decades 1, 3 and 4; the “Paleo-
zoic Fossils,” Vol. 1, parts I to 5; Pal. fos., Vol. 2, part 1; part
2 of which last is still unpublished. While residing in Mon-
treal he was a constant contributor to the Canadian Naturalist,
he also wrote important papers for the American Journal of
Science and Arts, New Haven, the Geological Magazine, Lon-.
don, and the Journal of the Canadian Institute, Toronto.

He was an indefatigable worker; from early morning till

Biographical Sketch of Elkanah Billings—Ami. 271

late at night he was at his desk, and later at home into the
hours of night he carried on his studies, and thus accomplished
much in those twenty years of official connection with the
Geological Survey of Canada.

Billings left behind him a large amount of unfinished work,
numerous and important lists of organic remains bearing up-
on the geology of the older provinces. Many of these lists
would form most important contributions to Canadian geol-
ogy, should they ever be published. As noted by Dr. Whit-
eaves in his obituary sketch and Jn Memoriam paper, Vol. 8,
No. 5, Canadian Naturalist and Quarterly Journal of Sci-
ence, p. 261, “Mr. Billings died before he could describe
the whole of the material he had studied and carefully
examined, including collections by Sir William E. Logan
and Professor (now) Dr. Robert Bell, in Gaspe, by Mr.
T. C. Weston, at Arisaig; T. Curry, at Port Daniel and Bay
of Chaleurs. The whole of the material from these localities
had been carefully examined, and it only remained to write
the descriptions of the different species, but this, alas, he was
not destined to’ accomplish.” Those who had the pleasure
and privilege to know Mr. Billings, state that he was char-
acterized “by great firmness and decision and an unswerving
love of truth and justice, and by an unaffected and winning
modesty of demeanor.”

During his lifetime Mr. Billings received many tokens of
appreciation. In 1867 the Natural History Society voted him
its silver medal for “his life-long efforts for the.promotion of
science in Canada.’”’ He was awarded a bronze medal (in
Class I.) by the jurors of the International Exhibition of
London in 1862, and a similar one at the Paris Exposition of
1867.

To do him honor and indicate to the world of science what
Billings did for Canadian geology, many a paleontologist in
America and Europe has described genera and species after
him. The genera Billingsia, Billingsite, Billingsella and El-
kania have been erected by Walcott, Hall, Ford and Hyatt,
whilst upwards of thirty species of corals, crinoids, brachio-
pods, lamellibranchs, molluscs, cephalopods, ostracods, tri-
lobites and other fossil organic remains bear his name.

272 The American Geologist. ae

BIBLIOGRAPHY OF ELKANAH BILLINGS.

On Some New Genera and Species of Cystidea from the Trenton Lime-
stone. (Read before the Canadian Institute, February 11th, 1854.)
Can. Journ., Toronto, pp. 215-218, April. Toronto. Hiustrated.

On Some New Genera and Species of Cystidea from the Trenton Lime-
stone. (Read Feb. 11th, 1854.) Can. Journ., pp. 250-253; May.
Toronto. Illustrated.

On Some New Genera and Species of Cystidea from the Trenton Lime-
stone. (Read before the Canadian Institute, April 8th, 1854.) Can.
Jour., pp. 268-274; June. Toronto. Illustrated.

1856. Lr

Elevation and subsidence of Land—Various theories of the Earth—
Origin of Stratified Rocks—European and American Formations—
Geological Distribution of the latter in Canada. Art. I.
an Nat. and Geol., Vol. 1. No. 1. pp. 1-25. February 1856. Mon-
treal.

On the Nomenclature and Classification of the Animal Kingdom. Art.
2., Can. Nat. and Geol. Vol. 1. No. I. pp. 26-31. February. Montreal.

Fossils of the Potsdam Sandstone; Sea-weeds, shells and foot prints
on the rock at Beauharnois. Art. 3., Can. Nat. and Geol., Vol. 1. No.
I. pp. 32-39. February 1856. Montreal.

On Some of the characteristic’ Fossils of the Lower Silurian rocks of
Canada. Art. 4., Can. Nat. and Geol., Vol. 1. No. I. pp. 39-47. Feb-
ruary ; Montreal.

On the Crinoidea or Stone Lilies of the Trenton Limestone, with a de-
scription of a new species. Art. 5., Can. Nat. and Geol. Vol. 1. No.
I. pp. 47-57. February, 1856; Montreal.

Fossils of the Lower Silurian Rocks. Niagara and’ Clinton Groups.
Art. 6., Can. Nat. and Geol., Vol. 1. No. 1. pp. 57-60. Montreal.
Natural History of the Moose Deer, Alces Americana. Art. 7, Can.

Nat. and Geol.. Vol. 1.. No. 1. pp. 60-70. Montreal.

The Northern Reindeer, or Barren Ground Caribou (Tarandus arcti-
cus) Art. 8., Can. Nat. and Geol., Vol. 1. No. 1. pp. 71-76. February.
Montreal.

The Woodland Caribou. (Tarandus hastalis) Art. 9., Can. Nat. and
Geol., Vol. 1. No. 1. pp. 77-80. February. Montreal.

On the Wapite, or Canadian Stag (Elaphus Canadensis). Art. 10., Can.
Nat. and Geol., Vol. 1. No. 2. pp. 81-87. April. Montreal.

~n the Common* Deer (Cervus Virginianus). Art. 11., Can. Nat. and
Geol., Vol. 1. No. 1. pp. 87-92. April. Montreal.

. rofessor Dawson on New Species of Meriones. Can. Nat. and Geol.,
Vol. 1, No. 1, p. 80. February, 1856. Montreal. (Notice of paper.)

1856.

On the Mule Deer, (Cervus Macrotis). Art. 12., Can. Nat. and Geol..

Vol. 1. No. 2. pp. 92-100. April. Montreal.

On the American or Black Bear, (Ursus Americanus). Art. 13, Can.
Nat. and Geol., Vol. 1. No, 2. pp. too-ro4. April. Montreal.

On the Grizzly Bear, (Ursus Ferox). Art. 14., Can. Nat. and Geol..
Vol. 1. No. 2. pn. 104-109. April. Montreal.

On the White or eee Bear, (Ursus Maritimus). Art. 15. (Cant Nat
and Geol., Vol. No. 2. pp. to9-113. April. Montreal.

On the Cinnamon Bae: (Ursus Cinnamomun). Art. 16., Can. Nat. and
Geol.. Vol. 1. No. 2. pp. 114-115. April. Montreal.

On the Fossil Corals of the Lower Silurian Rocks of Canada. Art. 17..
Can. Nat. and Geol., Vol. 1. No. 2. pp. 115-128. April. Montreal.
On Some of the Technical Terms used in the description of Fossil
Shells. Art. 18.. Can. Nat. and Geol., Vol. 1. No. 2. pp. 128-131.

April. Montreal.

Biographical Sketch of Elkanah Billings——Ami. 273

On Some of the Fossil Shells of the Clinton and Niagara formations.
Art. 19., Can. Nat. and Geol., Vol. 1. No. 2. pp. 131-139. April.
Montreal.

Ornithology. Technical terms. Art. 20. Can. Nat. and Geol., Vol. 1. No.
2. pp. 139-142. April. Montreal.

_On the Robin or Migratory Vhrush, (Tudus migratorious.) Art. 21,

Can. Nat. and Geol., Vol. 1. No. 2. pp. 142-146. April. Montreal.

On Black Duck, (Anas obscura). Art. 22, Can. Nat. and Geol., Vol. 1,
No. 2, pp.,146-140. April. Montreal.

On the Wood Duck, (Anas Sponsa). Art. 23, Can. Nat. and Geol.,

~ Vol. 1, No. 2, pp. 149-152. April. Montreal.

On the Green-Winged Jleal, (Anas Carolinensis). Art. 24., Can. Nat.
and Geol., Vol. 1. No. 2. pp. 153-154. April. Montreal.

On the Blue-Winged Teal, (Anas discors). Art. 25 Can. Nat. and
Geol., Vol. 1. No. 2. pp. 154-156. April. Montreal.

On the Mallard, (Anas boschas). Art. 26, Can. Nat. and Geol., Vol. 1,
No. 2. pp. 156-159. April. Montreal.

On a Sea Gull Shot at Ottawa. Art. 27., Can. Nat. and Geol., Vol. 1.
‘No. 2. pp. 159-160. April. Montreal.

On the Pigeon, (Ectopistes migratoria). Art. 29, Can. Nat. and Geol.,
Vol. 1. No. 3. pp. 168-176. June. Montreal.

On the species of Wood Peckers, observed in the vicinity of the City
of Ottawa. Art. 30. Can. Nat. and Geol., Vol. 1. No. 3. pp. 176-180.
June. Montreal.

A Chapter on Earthquakes. Art. 31., Can. Nat. and Geol., Vol. 1. No. 3.
pp. 189-195. June. Montreal.

On some of the Common Rocks of the British Provinces. Art. 32., Can.
Nat. and Geol., Vol. 1. No. 3. pp. 196-202. June. Montreal.

On some of the Lower Silurian Fossils of Canada. Art. 33., Can. Nat.
and Geol., Vol. 1. No. 3. pp. 203-208. June, 1856. Montreal. (With
23 wood cuts).

Natural History of the Wolf, (Canis Lupus), and its Varieties. Art.
34., Can. Nat. and.Geol., Vol. 1. No. 3. pp. 209-215. June. Montreal:

On the Foxes of British North America. Art. 35., Can. Nat. and Geol.,
Vol. 1. No. 3. pp. 216-228. June. Montreal.

On the Canadian Otter, (Lutra Canadensis). Art: 36., Can. Nat. and
Geol., Vol. 1. No. 3. pp. 228-232. June. Montreal.

On the Bob-link or Rice-bird, (Dolichonyx orzivora). Art. 37, Can.
Nat. and Geol., Vol. 1. No. 3. pp. 232-237. June. Montreal:

Natural History of the Wolverine or Carcajou, (Gulo Luscus). Art.
39., Can. Nat. and Geol., Vol. 1. No. 4. pp. 241-246. September.
Montreal.

On the Loup Cervier or Canadian Lynx, (Lynx Canadensis), and the
Bay Lynx, or Wild Cat of the United States, (Lynx Rufus). Art.
40, Can. Nat. and Geol., Vol. 1, No. 4, pp. 247-252. September.
Montreal.

Natural History of the Racoon, (Procyon Lotor). Art. 41., Can. Nat.

and Geol., Vol. 1. No. 4. pp. 253-260: September. Montreal.

On some of the Game Birds of Canada. Art. 44. Can. Nat. and Geol.,
Vol. 1. No. 4. pp. 284-305. September. Montreal.

On the Insects injurious to the Wheat Crop. Art. 45., Can. Nat. and
Geol., Vol. 1. No. 4. pp. 306-312. September. Montreal.

Description of Fossils occurring in the Silurian Rocks of Canada. Art.
46., Can. Nat. and Geol., Vol. 1. No. 4. pp. 312-320. September.
Montreal. :

‘On the Tertiary Rocks of Canada, wth some account of their Fossils.
Art. 47., Can. Nat. and Geol., Vol. 1. No. 5. pp. 321-346. December.
Montreal.

On the American Buffalo, (Bison Americanus). Art. 48., Can. Nat. and
Geol., Vol. 1. No. 5. pp. 346-353. December. Montreal.

274 The American Geologist. MAE. LOE:

On the Musk Ox, (Ovibos moschatus). Art. 49, Can. Nat and Geol.,.
Vol. 1. No. 5. pp. 353-357. December. Montreal.
The Rocky Mountain Sheep, (Ovis montana). Art. 50, Can. Nat and
Geol., Vol. 1. No. 5. pp. 357-360. -December. Montreal. :
On the Skunk, (Mephitis chinga). Art. 51, Can. Nat. and Geol., Vol.
1. No. §. pp. 360-364. December. Montreal.

tn the Canada Porcupine, (Hystrix dorsata). Art. 52, Can. Nat. and ~
Geol., Vol. 1. No. 5. pp. 364-369. December. Montreal.

On the Northern Hare, (Lepus Americanus). Art. 53., Can. Nat. and
Geol., Vol. 1. No. 5. pp. 369-379. December. Montreal. ~

On the Mammoth and Mastodon. Art. 54, Can. Nat. and Geol., Vol.
1, No. 5, pp. 379-390. December, 1856. Montreal.

1857.

On the several Species of Squirrels inhabiting the British Provinces.
Art. 57., Can. Nat. and Geol., Vol. 1. No. 6. pp. 431-442. January.
Montreal.

On the Great Horned Owl, Bubo Virginianus. Art. 58., Can. Nat. and
Geol., Vol. 1. No. 6. pp. 443-447. Janaury. Montreal.

On the Snowy Day Owl, Surnia Nyctea. Art. 59., Can. Nat. and Geol...
Vol. 1. No. 6. pp. 447-450. January. Montreal.

The Enemies of the Wheat Fly. Art. 60., Can. Nat. and Geol., Vol. 1.
No. 6. pp. 450-457. January. Montreal.

Natural History from ‘‘Glaucus, or the Wonders of the Shore.” Art.
61., Can. Nat. and Geol., Vol. 1. No. 6, pp. 457-464.

Lawrencian iormation. Can. Nat. and Geol., Vol. 1, No. 6, January,
1857, p. 464, Montreal.

Fosslls of the Hamilton Group. Art. 63., Can. Nat. and Geol., Vol. 1.
No. 6. pp. 472-479. January. Montreal.

New Species of Fossils from the Silurian rocks of Canada. Report of
Progress Geol. Sur. Can. 1853-54-55-56., pp. 256-345., Toronto.

Report for the vear 1856 of E. Billings, Esq., Palaeontology, addressed’
to Sir Wm. E. Logan, Prov. Geologist, Geological Survey of Can-
ada. Report of Progress for years 1853-54-55-56, pp. 247-345. To-
ronto.

1857.

On the great iron ores of Canada and the cost at which they may he
worked. Can. Nat. and Geol., Vol. 2. No. 1., Art. 3, pp. 20-28. March,
1857. Montreal.

On the Natural History of the Rosignol or Song Sparrow, Fringilla
melodia. Can. Nat. and Geol., Vol. 2. No. 1. Art. 7. pp. 47-52. March.,.
1857. Montreal.

The late Mr. Hugh Miller. Can. Nat. and Geol., Vol. 2, No. 1, uu.
66-72. _March, 1857. Monteral.

Notes on “the Natural History of the Mountain of Montreal. Can. Nat.
and Geol., Vol. 2. No. 2., Art. 10. pp. 92-101. May, 1857. Montreal.
The Muskrat, (Fiber Zibethicus). Can. Nat: and Geol., Vol. 2. No. 2:

Art. 12. pp. 106-111. May, 1857. Montreal.

On the Wood-Chuck, (Arctomys Monax). Can. Nat. and Geol., Vol. 2..
No. 2. Art. 13. pp. 112-116. May, 1857. Montreal.

On the Fisher or Pekan. ‘‘Pennant’s Martin” (Mustela Canadensis)
Can. Nat. and Geol., Vol. 2. No. 2. Art. 14, pp. 116-119. May, 1857.
Montreal.

On the Beaver. Castor fiber. Can. Nat. and Geol., Vol. 2. No. 2. Art. 15.
pp. 120-127. May, 1857. Montreal.

On the Genera of Fossil Cephalopoda occurring in Canada. Can. Nat. and’
oe Vol. 2, No. 2, Art. 17, pp. 135-138, pl. 2, May, 1857. Montreal.

late 2.

Biographical Sketch of Elkanah Billings —Anu. 275

Description of some fresh water Gasteropoda inhabiting the Lakes and
Rivers of Canada: Can. Nat. and Geol., Vol. 2. No. 3. Art. 22. pp.
195-215 (printed 115). July. 1857. Montreal.

On the Order Lepidoptera with the description of two species of Cana-
dian Butterflies. Can. Nat. and Geol., Vol. 2. No. 3. Art. 23. pp. 215
(printed 115) 226. July, 1857. Montreal.

Eleventh Meeting of the American Association for the Advancement 9f
Science. Can. Nat. and Geol., Vol. 2. No. 4. Art. 24. pp. 242-299.
September, 1857. Montreal.

Description of four species of Canadian Butterflies. Can. Nat. and Geol.,

' Vol. 2. No. 4. Art. 27. pp. 310-318. September, 1857. Montreal.

Description of four species of Canadian Butterflies, (Continued). Can.
Nat. and Geol:; Vol. 2. No. 5. pp. 345-355. (Art. 31). November,
1857. Montreal.

Farther Gleanings from the Meeting of the American Association in
Montreal. Can. Nat. and Geol., Vol. 2. No. 5. Art. 32. pp. 355-359.
November, 1857. Montreal.

Abstract of Professor Ramsay’s paper on the Geological Survey of
Great Britain. Can. Nat. and Geol., Vol. 2. No. 5. Art. 33, pp. 350-
365. November, 1857. Montreal.

Abstract of Dr. Rae’s account of the Expedition in search of Sir J.
Franklin. Can. Nat. and Geol., Vol. 2. No. 5. Art. 34. pp. 365-369.
November, 1857. Montreal.

On the Star-Nosed Mole of America. Can. Nat. and Geol., Vol. 2. No.
5. Art. 38. pp. 446-448. December, 1857. Montreal.

On the Mink, (Putorius vison). Can. Nat. and Geol., Vol. 2, No. 6.
Art. 39. pp. 448-455. December, 1857. Montreal.

The Common Weavel, (Putorius erminea). Can. Nat. and Geol., Vol. 2,
No. 6. Art. 40. pp. 455-462. December, 1857. Montreal.

On the Pine Marten, (Mustela martes). Can. Nat. and Geol., Vol. 2.
No. 6. Art. 41. pp. 463-464. December, 1857. Montreal.

1858.

Professor Owen on the classification of mammalia. Can. Nat. and Geol..
Vol. 3. No. 1. Art. 7. pp. 51-63. February, 1858. Montreal.

Geological Gleanings. Can. Nat. and Geol., Vol. 3. No. 2. Art. 14. pp.
122-139. April, 1858. Montreal. -

Geological Gleanings. Can. Nat. and Geol., Vol. 3. No. 3. Art. 18. pp.
182-192. June, 1858. Montreal.

On the Cystidea of the Lower Silurian rocks of- Canada. Geol. Sur.
Can., Figures and Descriptions of Canadian Organic Remains. De-
cade 3. Montreal.

- New Genera and Species of Fossils from the Silurian and Devonian

formations of Canada. Can. Nat. and Geol., Vol. 3. No. 6. Art. 34.
pp. 419-444. December, 1858. Montreal.

1850.

Report for the year 1857. Geol. Sur. Can.,, Report of Progress, 1857,
pp. 147-192, with 24 figures.

On Some New Genera and Species of Brachiopoda from the Silurian
and Devonian rocks of Canada. (From the Rep. G. S. Can. for 1858,
not printed in this Rep., however). Read before Nat. Hist. Soc. of
Montreal, March 28th, 1859. Can. Nat. and Geol., Vol. 4. No. 2. pp.
131-135. April, 1859. Montreal.

Description of a New Genus of Brachiopoda and on the Gentis Cyrto-
donta. Can. Nat. and Geol., (From Rep. Geol. Sur. for 1858-59, un-
published). Vol. 4. No. 4. pp. 301-303. August, 1859. Montreal.

Fossils of the Calciferous Sandrock including those of a Deposit of
White Limestone at Mingan supposed to belong to this formation.

276 The American Geologist. May, 1901.

Can. Nat. and Geol., (Extracted from the Rep. Geol. Sur. Can. 1858-
1859, but not printed) Vol. 4. No. 5. pp. 345-307. October, 1859. Mon-
treal.

Fossils of the Chazy Limestone with Descriptions of New Species. Can.
Nat. and Geol., (Extracted from Rep. Geol. Sur. Can. 1858-1859,
but not printed in this Rep.). Vol. 4. No. 6. pp. 426-470. December.
1859. Montreal.

Artypa hemuicata, Can. Journ., new ser., Vol. 4, p. 316, 1859. Toronto.

1860.

Note on Conocephalites, Addendum to Description of a New Trilobite
from the Fotsdam Sandstone, by F. H. Bradley. Amer. Journ. Sc.,
Vol. 30. 2nd series, pp. 242-243. New Haven, Conn., U. S. A.

Description ot Some New Species of Fossils from the Lower and Mid-
dle Silurian Rocks of Canada. (From the Rep. of the Geol. Sur.
for 1860, no such report published). Can. Nat. and Geol., Vol. 5. No.
1. Art. 6. pp. 49-69. Montreal.

On the Fossil Corals of the Devonian Rocks of Canada West. (IIl.)
Can. Journ. Series 2. Vol. 4. pp. 97-140. Toronto.

On the Fossil Corals of the Devonian Rocks of Canada West. (IIl.)
Can. Journ. Series 2. Vol. 5. pp. 242-282. Toronto.

On the Fossil Corals of the Devonian Rocks of Canada West. (IIll.)
Can. Journ. Series 2. Vol. 6. pp. 138-148. Toronto.

“Canadian Geology and a Supplementary Chapter Thereto,’ Rewiew of,
Can. Nat. and Geol., Vol. 5. No. 6. Dec. 1860. pp. 450-455. Montreal.

“Description of a new Paleozojc Starfish of the Genus Palaeaster from
Nova Scotia.” Can. Nat. and Geol., Vol. 5. No. 1. Art. 7. February,
1860. pp. 69-70.

On Some New Species of Fossils from the ee near Point Levis
opposite Quebec. By E. Billings, Can. Nat., Vol. 5, p. 301. 1860.
August, 1860. 24 pp. Date and place of eae not indicated in
extras.

On the Fossils Corals of the Devonian Rocks of Canada West. (ill.)
Can. Journ. series 2. Vol. 6. pp. 253-274. Toronto.

On the Fossils Corals of the Devonian Rocks of Canada West. (IIl.)
Can. Journ. Series 2. Vol. 6. pp. 329-363. Toronto.

(Also published as Extract from the Report of the Geological Sur-
vey of Canada for 1860: 41 pp.)

On the Devonian Fossils of Canada West. Can. Journ. N. S. Vol. 5. pp.
249-282, May. Toronto. Issued separate, 99 pp. of which pp I-34
(both inclusive) were published in_ 1860 in Vol. 5. Can. Journ. ; the
rest in 1861 in Vol. 6 of the same Journal.

1861.

On the occurrence of Graptolites in the base of the Lower Silurian.
Canad. Nat., Vol. 6, pp. 344-348, 1861. Montreal.

On the Devonian Fossils of Canada West. Can. Journ. N. S. Vol. 6. pp.
138-148. March. Toronto.

On the Devonian Fossils of Canada West. Can. Journ. N. S. Vol. 6.
pp. 253-274. May. Toronto.

On the eetdnign Fossils of Canada West. Can. Journ. N. S. Vol.
pp. 239-363. plate 1. July. Toronto.

On the Age of the Red Sandstone formation of Vermont. Amer. Journ.
Sc. Art. 31. Ser. 2. Vol. 32. pp. 232. November, 1861. New Haven,

Conn. U. S. A.

On the Devonian Fossils of Canada West. (Extracted from the Re-
port of the Geological Survey of Canada for 1860, in preparation.
Published in the Canadian Journal as follows: Pages 1 to 34, in-

se ghee

Biographical Sketch of Elkanah Billings—Ami. 277

cluding A. Chloe, May 1860; pages 34 to 44, March 1861; pages 45-
65, May 1861; pages 66 to 99, July 1861.) Toronto.

Note on Conocephalites, Addendum to Description of a new Trilobite
from the Potsdam Sandstone by F. H. Bradley. (Republished)
Proc. Amer. Assoc. Adv. Sc. Vol. 14. pp. 161-166. (3 wood cuts).

Tt. On Some New or Little Known Species of Lower Silurian Fossils
from the Potsdam Group (Primordial Zone). In “Appendix” to Rep.
on the Geol. of Vermont. Vol. 2. pp. 942-955. Fig. 341-365. (Includes
description of Astylospongia parvula, from the Trenton Formation
of Ottawa, Can.) 1861, Claremont, New Hamshire.

.2. On Some New Species of Fossils from the Calciferous, Chazy,

Black River and Trenton Formations. In “Appendix to Report on
the Geol. of Vermont., Vol 2., pp. 955-960. Claremont, New Hamp-
shire.

1. On Some now or little known Species of Lower Silurian Fossils
from the Potsdam Group. (Primordial Zone.) Geol. Surv. of
Can., Pal. Foss., Vol. 1., pp. 1-18. Nov. Montreal.

2. On some new Species of Fossils from the Calciferous, Chazy, Black
River and Trenton Formations. Geol. Surv. Can. Pal Foss., Vol.
I., pp. 18-24., Montreai.

Note on a New Genus of Brachiopoda. Can. Journ., Vol. 6, pp. 148-
149 Toronto.

1861.

“Description of the New Species of Lingula referred to in the forego-
ing paper.” Can. Nat. & Geol., Vol. 6, pp. 150-151, (1861). Mon-
treal. Lingula Eva.

On Some of the Rocks and Fossils occurring near Phillipsburg, Can-
ada East. Can. Nat. & Geol., Vol: 6, Art. 23, pp: 310-328. With six
engravings.

1. Magnesian Limestone and Underlying Slate., pp. 310-311.

2. Blue, thin-bedded and Nodular Limestones, pp. 311-315.

3. Description of Some of the New Species referred to in the
foregoing paper, pp. 316-323.

4. Grey and Red Sandstones, Aug., 1861, pp. 323-328. Montreal.

1862.

Remarks upon Prof. Hall’s recent publication, entitled “Contributions
to Pajeontology.” Can. Nat., Vol. 7, pp. 389-393. 1862

2. On some new Species of Fossils from the Calciferous, Chazy,
Black River and Trenton Formations. Geol. Sury. Can., Pal. Foss.,
Vol. 1., pp. 24-56, Montreal.

On the Date of the recently published Reports of the Superintendent
of the Geological Survey of Wisconsin, exhibiting the progress of
the work. Jan. 1, 1861. Madison, Wis.: E. A. Calkins & Co., State
printers. pp. 52 8vo. Amer. Journ. Sc., Ser. 2, Vol. 33. pp. 420-421.
May, 1862. New Haven Conn., U. S. A.

Correction of the Article on the Red Sandrock in this volume, page
100, Amer. Journ. Sc., Ser. 2. Vol. 33. pp. 421-422. May, 1862.
New Haven, Conn., soe:

Further Observations on the Age of the Red Sandrock Formatio::
(Potsdam Group of Canada and Vermont. Amer. Journ. Sc., Vol.
33, 2nd series, pp. 100-105. New Haven, Conn.

On Some New Species of Fossils from the Quebec Group. Geol. Sur.
Can. Pal. Foss., Vol 1, pp.57-06. (June, 1862.) Montreal.

New Species of Fossils from different Parts of the Lower, Middle and
Upper Silurian Rocks of Canada, Part 4. Geol. Sur. Can., Pal.
Foss., Vol. 1., pp. 96-185. (pp. 96-168, June; 1862.) pp. 169-185.
(1865). Montreal.

278 The American Geologist. RES: Ane

'
1863.

On the Genus Centronella with Remarks on some of the Genera of
Genera of Brachopodia. Amer. Jour. Sci., Vol. 36, pp. 236-240.
New Haven, Conn., U. >. A.

Catalogue of the Lower Silurian Fossils of Canada, not including
those of the Quebec Group. Geology of Canada, Geol. Sur. Can.,
1863. pp. 937-954. Montreal.

Geology of Canada. Report of Progress from its commencement to
1863. Geological Survey of Canada, 1863. (Palaeontology by E.
Billings.) pp. 1-453. (A large proportion of the volume.) Montreal.

Description of some new Species of Fossils with Rmarks on others al-
ready known, from the Silurian and Devonian Rocks of Maine.
Proc. Portland Soc. Nat. Hist., Vol. 1., pp. 104-126. - Portland, Me.

On the Parallelism of the Quebec Group with the Llandeilo of Eng-
land and Australia. and with the Chazy and Calciferous Forma-
tions. Can. Nat. & Geol., Vol. 8., pp. 19-35. Montreal.

Description of a new species of Phillipsia, from the Lower Carbonifer-
ous rocks of Nova Scotia. Can. Nat. Geol., Vol. 8, No. 3, Art. 17,
pp. 209-210, June, 1863, Montreal.

Description of a new species of Harpes from the Trenton Limestones,
Ottawa. Can. Nat. and Geol., Vol. 8, No. 1, pp. 36-37.

‘On the internal Spiral coils of the Genus Cyrtina, Can. Nat. and Geol.,
Vol. 8, No. 1, pp. 37-35, Feb., 1863.

List of fossils from the various bands at Point Levis. Geology of
Canada. Geol. Surv. Can., pp. 862-864, 1863. Montreal.

‘On the genus Stricklandia; proposed alteration of the name. Can.
Nat. and Quart. Journ. Sci., Vol. 8, p. 370. Montreal.

1864.

“Note by E. Billings, F. G. S.,” accompanying paper ‘On Leskia
mirabilis, (Gray)” from the Geol. Mag., Vol. 5, p. 179. London,
England. Separate: Can. Naturalist, pp. 5-8.

1865.

taleozoic Fossils, Vol. 1. Containing Descriptions and Figures of New
or Little Known Species of Organic Remains, from the Silurian
Rocks. Geol. Sur. Can., 426 pp.. with 4or engravings. (1861-1865).
Montreal.

New Species of Fossils from the Limestones of the Quebec Group,
from Point Levis and one Localities in Canada East. Geol. Sur-
Can., Pal. Foss., Vol. 1., pp. 185-206. (part 5.) Feb., 1865. Mon-
treal.

New Species of Fossils from the Quebec Group in the Northern Part
of Newfoundland. Geol. Sur. Can., Pal. Foss., Vol. 1., pp. 207-300.
(Part 6.) Montreal.

New Species of Fossils from the Quebec Group in Eastern Canada,
with some others previously described, and some from other Forma-
tions. Geol. Sur. Can., Pal. Foss., Vol. 1, pp. 301-338, (Part 7.)
Montreal.

New Species of Fossils from the Calciferous Formations, with Re-
marks on some others previously described. Geol. Sur. Can., Pal.
Foss. Vol. 1., pp. 339-361, (Part 8.) Montreal.

New Species of Eossils from the Quebec Group in the Northern Part
of Newfoundland, with a few from the Potsdam Group. Geol.
Sur. Can., Pal. Foss.. Vol. 1., pp. 361-377. (Part 9.) Montreal.

Fossils from Various Formations in the Silurian and Devonian Sys-
tems. Geol. Sur Can., Pal. Foss., Vol. 1., pp. 377-395. (Part 10.)
Montreal.

Biograthical Sketch of Elkanah Billings —Amnu. 279

Species from the Quebec Group published in 1860, Geol. Sur. Can., Pal.
Foss., Vol. I., pp. 395-415 (Part 11). Montreal.

“Notes on some of the more remarkable genera of Silurian and Devon-
ian fossils.” By E. Billings, F. G. S., (issued as separate, I5 pp.»
Can. Nat and Geol., New Series, Vol. 2, No. 3, pp. 184-198. Medium
of publication and date not indicated. (In part reproduced as Part
to of Pal. Foss., Vol. 1, 1865.. :

1866.

‘Catalogues of the Silurian Fossils of the Island of Anticosti, with
Descriptions of some new Genera and Species, includes also New
Species of Fossils from the Clinton and Niagara Formations (of
Ontario). Geol. Sur. Can., 93 pp., Montreal, Nov., 1866.

Reviewed in Amer. Journ. Sc., 2nd series, Vol., 43. pp. 259-260. New
Haven, Conn., U. S. A., 1860.

1867.

On the classification of the Subdivisions of McCoy’s genus Athyris as
determined by the Laws of Zoological Nomenclature.’ Amer.
Journ. Sc., Ser. 2, Vol. 44, pp. 48-61, 1867. New Haven; also in An-
nals and Mag. Nat. Hist., Ser. 3, Vol. 20, pp. 233-247, London, Eng.

patusee géologique du Canada. ‘“‘Restes Organiques,” pp. 43-49, Paris,

1867.
1868.

Description of two New Species of Stricklandinia. Geol. Mag., Vol. 5,
No. 2 (vages I-6 in separate), plate 4, 8 figures; February, 1868.
London, Eng.

1869-1870.

Notes on the Structure of the Crinoidea, Cystidea and Blastoidea. Can.
Nat. and Quart. Journ. Sc., new series, Vol. 4, No. 3, pp. 277-203;
September, 1869, Montreal; (to be continued). mew series (same
title), Can. Nat. and Quart. Journ. Sc., N. S., Vol.-4, Dec., 1869, pp.
426-433, (to be continued). [Concluded under title: ‘Notes on the
Structure of the Crinoidea and Blastoidea.” Can. Nat. and Quart.
Journ. Sc., new series, Vol. 5, pp. 180-198, June, 1870, and reprinted
from the Amer. Journ. Science and Arts,. Vol. 50, Sept., 1870. New
Haven. |

1870.

Notes on the structure of the Crinoidea, Cystidea and Blastoidea. (1)
Amer. Journ. of Sc. and Arts, 2nd Ser., Vol. 47, pp 69-83; (2)
ibid, Vol. 49. pp. 51-58, 1870; (3) ibid, Vol. 50, pp. 225-240, 1870,
New Haven, Conn.; Annals and Mag. Nat. Hist. (1) 4th Series,
Vol. 5, pp. 251 and 409: (2) Vol. 7, p. 142, London, England.
and Quart. Journ. Sc. Vol. 5. pp. —. Montreal; and in Annals and
Mag. Nat. Hist. (1) 4th Series, Vol. 5, pp. 251-2109; (2) Vol. 7,
pp. 142. London, Eng.

Note on the structure of Balastoidea, Amer. Journ. Sc. and Arts,
Ser. 2, Vol. 47. p. 353. Also printed as separate from Amer. Journ.
£c. and Arts, Vol. 50, Sept., 1870, 16 pn.

Note on Some specimens of Lower Silurian Trilobites. Quart. Journ.
Geol. Society, Vol. 26, November, 1870, pp. 479-486, Plates 31 and 32.
London, Eng. :

(Fossils from Rock Brook, New Brunswick) Geol. Sur. Can., Rep.
Propr. 1866-69, pp. 190 and 211. Montreal, 1870.

(Fossils from Riviere on Loup, Quebec) Geol. Sur. Can. Repert of
Progress, 1866-69, pp. 133 and 140, 1870, Montreal.

ty
oo
oe)

The American Geologist. May; Aen

1871.

On Some New Species of Palaeogoic Fossils, Can. Nat. and Quart.
eee Se. Vol. 6, pp. 213-222, Montreal. Also issued as separate,
15

Pranseed New Genus of Pteropoda. Genus Hyolithellus, N. G. Can.
Nat. and Quart. Journ. Sc. Vol. 6. No. 2. p. 240. Montreal, Dec.
1871. Also issued as separate. No pagination given.

Note on Trimerella acuminata, Annals and Mag. Nat. Hist. Ser. 4,
Vol. 8, pp. 140-141, London, Eng.; Amer. Journ. Sc. and Arts, Ser.
ce Vol. 1 pp. 471. New Haven, Conn.

Note on a Question of Priority. eer Journ: Sc. Ser:.3, Vole
270, 1871, New Haven, Conn. U. S. A

On the Canadian Tribobite with legs. (Extracted from the Canadian
Naturalist of December. 1871, pp. 11-15) forming part of paper -
Some New Species of Paleozoic Fossils by E. Billings,P. S. S.

(Fossils from Black Bay, New Brunswick) Geol. Sur. Can. Rep. ‘as
Progress, 1870-71, p. 161. 1872. Montreal.

Fossils from the so-called Huronian of Newfoundland. Amer. Journ.
Sc., Ser. 3, Vol. 3, pp. 223-224. (Brief abstract of papers read be-
fore Montreal and Nat. Hist. Soc. Jan. 1872). New Haven, Conn.
U A

Fossils probably of the Chazy era in the Eolian Limestone of West
Rutland, Vt. Amer. Journ. Sc.,.Ser. 3, Vol. 4, p. 133. New Haven.

Note on the Discovery of Fossils in the Winooski Marble at Swanton,
Vt. Amer. Journ. Sc., Ser. 3, Vol. 3, pp. 146-146. New Haven, Conn.
ake

Note on the Discovery of Fossils in the Winooski Marble at Swanton,
Vermont. N. S. Can. Nat. Vol. 6, p. 351. Montreal.

1873.

(Additional Notes on the Taconic Controversy. Can. Nat. and Quart.
Journ. Sc. Vol. 6. No. 4, pp. 460-465, 1872, Montreal

Remarks on the Taconic Controversy. Can. Nat. and Geol. New Series.
Vol. 6, No. 3, pp. 313-325. 1872, Montreal.

Reproduced without table of Geological formations, etc., in Amer.
Journ. Sc. and Arts, 3d Ser. 1. Vol. 3. pp. 467-471, ‘June, 1872, New
Haven.

On the Genus Obolellina. Can. Nat. and Geol. New Series, Vol. 6,
No. 3, pp. 326-333, (includes article on “A Question of Priority”
pp. 330-333. Reproduced in part in Amer. Journ. Sc. and Arts, 3d
Ser. Vol. 3. pp. 270. New Haven.

Un Some Fossils from the Primordial Rocks of Newfoundland. Can.
Nat. and Geol. N. S. Vol. 6. No. 4. pp. 465-479. 1872. Montreal.

(Fossils from Drury’s Cove, New Brunswick) Geol. Sur. Rep. Prog.
1870-71, p. 140, 1872.

On the Mesozoic Fossils from British Columbia. collected by Mr. Jas.
Richardson in 1872, Geol. Sur. Can., Rep. Prog. for 1872-73. Appen-
dix to Mr. Richardson’s report. np. 71-75. Montreal.

(Fossils found in Lower Cache Creek, British Columbia) Geol. Sur.
Can. Rep. Prog. 1871-72. p. 62. 1873. Montreal.

1874. -
Paleozoic Fossils, Vol. 2, pt. 1, 144 pp. 9 plates. Geol. Sur. Can. Mon-
treal. :
1. On some of the fossils of the Gaspé series of rocks. p. I- -64.
2. On some new species of fossils from the primordial rocks of
Newfoundland. pp. 64-78.
3. On the Genus Stricklandinia, with descriptions of the Can-
adian species. pp. 78-80.

| © Biographical Sketch of Elkanah Billings —dAmi. 281

4. Notes on the structure of the Crinoidea, Cystidea and Blas-
toidea. pp. 90-128.
5. On some of the Fossils of the Arisaig series of rocks. Upper
Silurian Nova Scotia. pp. 129-144.
«Note on fossils from Ballinac Islands, British Columbia. Geol. Sur.
Can., Rep. Progress, 1873-74. p. 98. Montreal. Published 1874.
On some new Genera and Species of Paleozoic Mollusca. Can. Nat. &
MOuart. Journ. Sc., vol. 7, No. 5, pp. 301-302, (Genera Ilionia and
Pterinotella)—July, 1874. Montreal.

On some new or little known fossils from the Silurian and Devonian
Rocks of Ontario. Can. Nat. & Quart. Journ. Sc., vol. vii, No. 4.

Pp. 230-240.
1876,

(List of Devonian Fossils prepared by E. Billings included on page 68
of “Report on the Country between the Assiniboine river and lakes
Winnipegosis and Manitoba,’ by J. W. Spencer.) Geol. Sur. Can.,
Rep. Progr., 1874-75, issued Montreal, 1876.

On the Structure of Obolella chromatica. Amer. Journ. Sc., Ser. 3,
Vol. XI, pp..176-178. New Haven, Conn., U. S. A.

ORIGINAL MICACEOUS CROSS-BANDING OF
STRATA BY CURRENT ACTION.

By J. B. WoopWworTH, Cambridge, Mass.

The process of sedimentation normally produces layers of
uniform texture parallel with the surfaces of the laminae.
Bands of different mineralogical and textural characters in-
clined to the planes of stratification are common in the meta-
morphic rocks as the result of mineralization of shear zones or
of the brecciation and mineralization of shear zones inclined
to the original sedimentation planes. The following descrip-
tion relates to a case in which a micaceous banding occurs as
an original structure at a high angle with the stratification
imitating the dual structure of some metamorphosed sediments.

The Fitchburg railroad one and a half miles east of Con-
cord, Mass., occupies a deep cut through a rude glacial sand-
plain which encloses lake Walden. In a side cutting in this
excavation, the writer observed in 18098 a bed of fine, brown
glacial sand about one foot thick sharply demarcated from
clays and sands above and below by certain peculiarities of
structure and texture. This layer was very regularly beset by
current-mark with westward facing steeper fronts, indicating
the drifting of the sediment in that direction during deposition.
The crests of the ridges were regularly superposed, each suc-
cessive layer having its crests at regular intervals somewhat

282 The American Geologist. May, 1901.

advanced to the westward upon the underlying one, giving a
crest plane inclination for the series of about 45° east.

The striking feature of the bed was a band of highly mi-
caceous sands forming the frontal slopes of the entire series
of crests in the bed as shown in the annexed figure, by the
shading.

FIG. I. CROSS-SECTION OF A PORTION OF THE LAKE WALDEN GLACIAL SAND
BED, SHOWING A CURRENT MARK WITH MICACEOUS BANDS IN THE
FRONTAL SLOPES OF THE CRESTS.

The micaceous bands were about half an inch in width.

They dipped 45° east, as stated above, parallel to planes pass- —

ing through the respective crests. The individual particles of
mica lay parallel to the crest slope, producing an obvious
false bedding totally distinct from the straticulate structure of
normal cross-bedding in relatively homogeneous sands. The
micaceous bands were between four and five inches apart.

The type of rippled stratification with which the micaceous
banding was associated shows that the banding developed un-
der the action of the vortical movements of the bottom drift o7
a slowly moving current. In analogy with the observed vor-
tices of a continuous bottom current, my colleague, Dr. Jaggar,
suggests the whirling movement of the water must have been
as in the annexed figure at the crest of each current mark. (See
fig. 2.) In the dead space on the frontal slope, particles of
mica which were caught in the bottom movements would come
to rest as the deposit grew upward.

FIG. 2. SCHEME OF VORTICAL MOVEMENTS ABOUT THE CREST OF A CURRENT
MARK. THE SHADED SLOPE SHOWS THE AREA ON WHICH THE PART-
ICLES OF MICA HAVE COME TO REST BENEATH THE NODE JUST IN AD-
VANCE OF THE CREST. (AFTER SKETCH BY JAGGAR. )

In this connection, it will be recalled that Spurr in this
Journal (vol. xiii, 1894, pp. 43-47, 201-206, with discussion by
Jaggar, pp. 199-201), described a rhythmic succession in tex-

Banding of Strata.—W oodworth. 283

ture parallel to the stratification resembling current or ripple
mark, but the textures were pebbly and sandy. In the Minne-
sota glacial deposit described by Spurr as in this case a cross-
banding was produced at about 45° to the true stratification.
Of the structure described by Spurr, the writer has seen no
examples and is therefore unable to make further comparison
of the two cases.

It will be noted that the simulation of the banding of met-
amorphic schists in the lake Welden case is remarkable, and
if the deposit existed as a firmly consolidated, slightly meta-
morphosed rock, it might be on hasty examination mistaken
for an ordinary deposit with its banding induced by the pro-
duction of new minerals. Where metamorphism and the pro-
duction of micaceous minerals take place without shearing as
in the quartz-albite-biotite rock of the “Devil’s foot ledge” in
the Carboniferous of Kingstown, Rhode Island, the secondary
mica may lie in the original planes of stratification, including
those of the cross-bedding. Moreover, it-is conceivable that
the metamorphism of a bed like that at lake Walden under
static conditions without deformation might lead to the reten-
tion of the essential arrangement of the original particles. The
writer is not aware, however, that any known mica-schists or
quartz-mica-schists exhibit evidence of this original distribu-
tion of their mineralogical components.

An analogous but not homologous structure exists in the
diagonal fissility of Van Hise in certain sheared and mineral-
ized sediments. Thus in the carboniferous gneissoid sand-
stones of Prudence Island in Narragansett Bay, these bands of
compact mineralized layers of arenaceous sediments alternate
with thicker layers of finer sediments less mineralized but be-
set by open planes of diagonal fissility inclined about 45° to the
bedding, this secondary structure occupying relatively to the
mineral banding the position held by the original beddine
planes to the micaceous banding in the glacial deposit above
described.

284 The American Geologist. May, oe

A HISTORICAL OUTLINE OF THE GEOLOGICAL
AND AGRICULTURAL SURVEY OF THE
STATE OF MISSISSIPPI.*

By E. W. HILGARD,; Late State Geologist, Berkeley, Cal.

The geological and agricultural survey of the state of Mis-
sissippi had its origin in an act of the legislature entitled “An
Act to further endow the University of Mississippi,” approved
March 5, 1850, which took effect on the first of June following.
This act is worded as follows:

Sec. 1. Be it enacted, &c., that the further sum of three thousand
dollars be and the same is hereby semi-annually appropriated, subject to
the draft of the President of the Board of Trustees of the University of
Mississippi, to be applied by them to the purchasing of books and ap-
paratus, and the payment of the salaries of professors and assistant pro-
fessors of agricultural and geological sciences in said University; pro-
vided that one-half only of the amount of said appropriation shall be
from the revenue in the treasury, and the other half shall be made out
of the sale of lands belonging to the seminary fund hereafter to be sold
as provided by law.

Sec. 2. That the authority required by the State Treasurer for the
payment of the trustees, shall be the warrant of the President of the
Board of Trustees, drawn in favor of any person whatever.

Sec. 3. That at least one-half of the amount herein appropriated
shall be expended in making a general geological and agricultural sur-
vey of the State, under the direction of the principal professor to be
appointed under the first section of the Act.

* Reprinted from the publications of the Mississippi Historical Society.

+Professor Eugene Woldemar Hilgard was born in Zweibriicken, Rhenish
Bavaria, Jan. 5, 1833. He emigrated to America in 1836. After completing
his collegiate education at Belleville, Ill., he took the degree of Ph. D., at
Heidelberg in 1853. He also studied at Zurich, and at Freiberg, Saxony.
The degree of LL. D. has been bestowed upon him by Columbia University,
the University of Michigan, and the University of Mississippi. He was state
geologist of Mississippi from 1855 to 1873, during which time he filled the
chairs of Geology and of Chemistry successively. In 1873 he accepted the
professorship of Geology and Natural History in the University of Michigan.
After two years’ service at this place he went to the University of California
as Professor of Agricultural Chemistry and Director of California Agricul-
tural Experiment Station and Dean of the Faculty of Instruction in Califor-
nia. He is at nresent actively engaged in the discharge of his duty at the
University of California, Berkeley, California. In 1860 his Report on Geol-
ogy and Agriculture in Mississippi was published by authority of the Staté
Legislature. This valuable work is still regarded as a standard authority on
the geological formations peculiar to Mississippi and the Southwest. In i880
he directed and edited the work on the report entitled “Cotton Production in
the U. 8.” (10th Census), to which he himself contributed detailed descrip-
tions of the agricultural features of Mississippi, Louisiana and California.
In 1894 he received the Liebig medal for distinguished achievements in agri-
cultural science from the Academy of Sciences, Munich, Bavaria.

In 1860 Dr. Hilgard married Miss J. Alexandrina Bello, daughter of Col.
Bello, of Madrid, Spain.

In spite of a comparatively feeble body, Mr. Hilgard’s vigorous intellect
and untiring energy have produced and published a large number of remark-
ably valuable papers upon topics of scientific interest and relating to a large
variety of subjects connected with his wide field of activity.—Eprror.

The Mississippi Survey.—Hilgard. 285

Sec. 4. That the survey herein provided for shall be accompanied
with proper maps and diagrams, and furnish full and scientific descrip-
tions of its rocks, soils and geological productions, together with speci-
mens of the same; which maps, diagrams and specimens shall be depos-
ited in the State Library and similar specimens shall be deposited in the
State University, and such other literary institutions in the State as the
Governor may direct; provided that the survey shall be made in every
county in the State.

Sec. 5. That the Trustees of the State University shall cause a report
to be made annually to the Governor, to be by him laid before each ses-
sion of the Legislature, setting forth, generally, the progress made in
the survey hereby required.

Sec. 6. That this Act take effect and be in force from and after the
first day of June next.

Under the somewhat loose provisions and phraseology of
this act Dr. John Millington, at the time professor of chemistry
at the University of Mississippi, was in June, 1850, appointed
to the position and additional duties provided for by it. No
assistant was obtained until July 15, 1851, when Oscar M. Lie-
ber, of South Carolina, was appointed to the position. No rec-
ord or report of Lieber’s work was made; during a portion of
his incumbency (presumably in autumn of 1852), he made, on
horseback, a reconnoissance of the Yazoo Bottom; but nothing
beyond that fact appears from the letters written by him un-
der the regulation defining his duties, which provides that
“When not actually engaged in making explorations and sur-
veys, he shall aid the principal professor of geology, agricul-
ture and chemistry in the discharge of his duties; and while
engaged in making such surveys, he shall make reports at least
monthly to the principal professor, and the salary of said as-
sistant professor shall be $1,000 per annum.’’ Lieber resigned
on January 14, 1852. :

In January, 1852, the position was accepted by Prof. B. L.
C. Wailes, then of the faculty of Jefferson College, near
Natchez. This gentleman had already made a collection of
rocks and fossils of thé southwestern part of the state, and
had quite an extended knowledge of the general features of
the latter. There was also passed by the legislature, in ses-
sion at the time, “‘an act to amend an act to further endow
the University of Mississippi, approved March 5, 1850,” the
provisions of which are as follows:

Sec. 1. That the fourth section of the above recited act be so amend
ed as to read “Zoological” instead of ‘“Gological’”’ productions.

286 The American Geologist. Mar tee

Sec. 2. That the room adjoining the State Library, formerly occu-
pied by the Surveyor-General, be appropriated and set apart for the de-
posit and safe-keeping of such specimens as may be collected during the
progress of the geological survey, provided for in the above recited Act;
and that the sum of 200 dollars be appropriated, out of any money in the
State Treasury not otherwise appropriated, to defray the expenses of fit-
ting up and preparing said room for the reception of said specimens.

Sec. 3. That the fitting up of said room shall be done under the di-
rection of the Governor, upon whose requisition the auditor shall issue
his warrant for the sum herein appropriated, or so much of said sum
as may be necessary.

Sec. 4. That the said room after being so fitted up shall be under the
charge of the State Geological Society, who shall be authorized to em-
ploy the librarian as curator of the same.

Sec. 5. That the said room shall be open to the public during such
hours as the State Library is now required by law to keep open, and
the librarian shall be allowed an additional compensation of $50 per
annum for the services required by the 4th section of this Act.

It will be noted that by the verbal correction made in the
first section of this act, the survey was practically made a com-
plete natural history survey; since the only branch not specit-
ically provided for—botany—might be understood to be nec-
essarily included in the provisions for an agricultural survey.
The State Society mentioned had but a very ephemeral exist-
ence. During the two succeeding years, viz: 1852 and 1853, Mr.
Wailes traveled chiefly in the southern and eastern part of the
state with his own team and outfit, examining the territory of
the cretaceous in northeast Mississippi and the tertiary and
quarternary areas in the southern part of the state.

Collections of tertiary fossils, especially from the shell bed
at Jackson, were sent by Wailes to Conrad, and mammalian
and other bones from the loess to Leidy, for determination
and description; and collections of these and other fossils as
well as of rocks were by him deposited, both at Oxford and
at Jackson.

In January, 1854, Wailes presented ‘to the Board of Trust-
ees of the University of Mississippi the manuscript of his re-
port on the work of the two preceding years, which was trans-
mitted through the governor to the legislature, with the rec-
ommendation that it be printed. The legislative committee
to whom it was referred reported back the following act, which
was passed and under which the survey was thereafter carried
on for a number of years:

The Mississippi Survey.—Hilgard. 287

AN ACT

To authorize the printing of the first annual report of the Agricultural
Geological survey of the State.

Sec. 1. Be it enacted by the Legislature of the State of Mississippi,
That two thousand copies of the report of Professor B. C. L. Wailes,
State Geologist, be printed under his supervision, in quarto form, and in
such manner, and with such illustrations and plates, as his excellency
the Governor shall deem appropriate and necessary for its illustration.

Sec. 2. Be it further enacted, That when printed and bound the said
report be deposited in the office of the Secretary of State, to be by
him distributed as follows: fifty copies to be deposited in the State
Library ; twenty-five copies to be deposited in the State University; one
copy to each state in the Union; one copy to be given to each incorpor-
ated college and academy in the State; one copy each to the Governor,
Secretary of State, Auditor of Public Accounts, State Treasurer, Ad-
jutant General, the Chancellor and Vice-Chancellors, the Judges of the
High Court of Errors and Appeals, the Attorney General, the Judge
and District Attorney of each District, each member of the present
Senate and House of Representatives, and one hundred copies to the
said State Geologist, to be by him exchanged for similar reports from
other states, and to furnish to scientific societies and public libraries.

Sec. 3. Be it further enacted, That one thousand copies of said re-
port shall be deposited in the office of the Secretary of State, to be sold
by any agent or agents to be appointed by the Governor, under such
regulations and for such sum as he may deem proper and advisable, for
the purpose of reimbursing the State for publishing the same, and the
balance to be distributed among the several counties of the State, in
proportion to their representation in the Legislature, to be furnished to
‘the people thereof, in such manner as the Boards of Police of the several
counties may direct.

Sec. 4. Be it further enacted, That previous to the printing of said
report, it shall be revised and completed by the said State Geologist;
and the portion of it which treats of Zoology, as far as prepared, shall
be omitted, and in lieu thereof, a catalogue of the fauna of the State, as
far as ascertained, shall be substituted.

Sec. 5.. Be it further enacted, That for the farther and more efficient
prosecution of the survey, analyses of the marls, soils, mineral waters,
and the chief agricuitural productions of the State, shall be made at the
University of Mississippi, as the Trustees may designate; and the State
Geologist may, from time to time, furnish such soils, marls and waters
as may be required for analysis, and shall receive in return from the
chemist full and precise reports of all analyses which may be made;
and specimens of soils and marls shall be preserved in convenient glass
bottles in the State Cabinet and in the Cabinet of the State University,
properly labeled with the chemical character of the substance and the
locality from which the same was obtained.

288 The American Geologist. May, 1901.

Sec. 6. And be tt further enacted, That the said Geologist shall make
collections of specimens to illustrate the mineral character and paleon-
tology of the State, in addition to the zoological productions which by
law he is now required to collect, and to cause them to be suitably
arranged and preserved in the State Cabinet, and in that of the Univer-
sity; and any duplicates that remain may be distributed by him among
such of the incorporated colleges of the State as may apply for them.

Sec. 7. And be it further enacted, That-a sum not to exceed two
thousand five hundred dollars be appropriated out of any money in the
treasury, to be drawn upon the requisition of the Governor, for the pur-
pose of carrying into effect the provisions of this Act.

Sec. 8. Be it further enacted, That this Act shall be in force from
and after its passage.

Approved March 1, 1854.

Wailes’ Report (the first of the Mississippi geological re-
ports), of which the publication was provided for by the above
act, bears the imprint of “E. Barksdale, State Printer, 1854,”
but was actually printed at Philadelphia, where Wailes re-
mained during the greater part of 1854 to superintend its pas-
sage through the press. The volume is an octavo of 371
pages, with 17 illustrations, partly of a historical character,
partly referring to the cotton industry; eight illustrate geo-
logical subjects, the most important being four plates of
shells from the Jackson shell bed, named and described by
Conrad. The report begins with a “historical outline’ coy-
ering 125 pages; a treatise on the agriculture of the state,
partly historical and dealing largely with cotton culture, fol-
lowed by some analyses of marls, cotton ashes and mineral
waters, and covering 81 pages; meteorological data, 12 pp.;
lists of fauna and flora, 46 pages ; appendices, with documents,
25 pages. This summary is sufficiently indicative of the fact
that Wailes was not, and did not write as a specialist in any
department. He makes no attempt to classify the rocks he
describes otherwise than as Cretaceous, Tertiary and Quarter-
nary, and inferentially classes among the latter the sandstone
of the Grand Gulf group, which is mentioned as overlying
“diluvial gravel.” He traces correctly the northern limit of
the Grand Gulf rocks from the Mississippi across Pearl river
to Brandon, and describes its occurrence in southwestern Mis-
SiSSIppt.

It will be noted that although the act of 1854 designates
Wailes as ‘‘state geologist,” it does not create that office,

The Mississippi Survey.—Hilgard. 289

which still remained an appendage of the chair of geology at
the University of Mississippi. It was expected that Wailes
would be elected to that chair, which in autumn 1853 had been
vacated by Dr. Millington. At an election held in June, 1854,
however, the choice for that position fell on Lewis Harper.*
Wailes, thereupon, immediately resigned his position,
which remained vacant until September, 1855. Up to the
. summer of 1855 Harper, bearing the titles of professor of ge-
ology and agriculture, and state geologist, had not taken the
field himself. He was now by action of the Board of Trust-
ees relieved from a portion of his duties as instructor, and
directed to take the field personally, for the purposes provided

for in the act. Besides, Dr. F. A. P. Barnard, then professor
of physics at the university, was requested to secure a com-

petent assistant geologist at-a salary of $1,000 per annum,
during a contemplated visit to the North. At the Providence
meeting of the Am. Ass’n Adv. of Science, August, 1855, Dr.
Barnard fulfilled his mission by tendering the appointment to
the writer (then lately returned from Europe), who promptly
accepted it, amid the sincere condolence of his scientific friends
upon his assignment to so uninteresting a field, where the
paleozoic formations (then occupying almost exclusively the
minds of American geologists), were unrepresented.

On the way south, a few weeks later, I paid a visit of sev-
eral days to Dr. David Dale Owen and his assistants, E. T.
Cox and S. S. Lyon (then engaged in the work of the Arkan-
sas state geological survey), at New Harmony, with a view of
obtaining suggestions for the work before me. This visit
was most important and fruitful in giving direction to my
subsequent studies and methods.

Reaching Oxford about the middle of September, 1855, I
found that Harper had then just returned from a rapid recon-
noissance of the cretaceous and tertiary prairie regions in
eastern Mississippi; and it was agreed that we should as soon
as possible set out on a joint exploration over the same route,
to be continued to the Gulf shore; thence across the southern
counties of the state to the Mississippi river. . The start was
made early in October, the outfit consisting of an ambulance

*Properly, Ludwig Hafner, of Hamburg, Germany, originally a student of
law, who for political reasons had to leave the country before graduation.

and subseauently became interested in natural history; then a teacher of
natural science at an academy near Greenville, Alabama.

29Q The American Geologist. May. 42034

carrying a camping outfit, and a negro driver, who at the same
time performed the office of cook. The cretaceous prairie
country on the Tombigby river was reached near Okolona,
whence the route lay through Aberdeen to Columbus; thence,
leaving the cretaceous territory, through Neshoba and Kem-
per counties to Enterprise on the Chickasawhay river, and
along that stream, crossing all the marine tertiary stages, as
far south as Leakville, Green county. It then became appar-
ent that there was not time to reach the coast, as intended,
without the risk of being caught in a very remote and thinly
settled region, by the early winter. We therefore turned west-
ward at once and reached the Mississippi at Fort Adams, from
which point we took steamer passage to Memphis, Tenn.

This expedition was made too rapidly and with too few
facilities for making collections, to afford anything more than
a very general insight into the character and relations of the
several cretaceous and tertiary stages. It was shown conclu-
sively that the dip of all the marine tertiary beds is southward,
except only as regards the Grand Gulf rocks, whose relations
to the rest we had no opportunity of observing, since they are
unrepresented in the Chickasawhay section, save by clays of
which the equivalence was not then apparent.

Meanwhile it had become apparent to the University trust-.

ees that in its present form the survey was in more than one
respect a burden to the University; and, accordingly, at the
legislative session of 1855-6, Governor McRae, in transmitting
to the legislature the regular report of the trustees of the Uni-
versity of Mississippi, accompanies it by a special message 1n
which occurs the following passage :

“The first portion of the trustees’ report relates to the geo-
logical survey of the state geologist, and proposes the separa-
tion of this survey from the University; and asks that it may
be taken charge of by the state, as an independent work un-
der the direction of the governor. The reasons for this are
fully set forth in the report, and may be recapitulated in brief
as follows:

1. The geological survey does not form a part of the course of in-
struction in the University, and is not properly connected with the bus!-
ness of the institution.

2. The duties of the State Geologist, under the present arrangement,
being partly as professor in the University, partly in the field survey,

The Mississippi Survey.—Hilgard. 291

neither position can be fully or satisfactorily filled by him. Either the
classes in this department must suffer in his absence, or the survey in
the field be neglected to give them proper attention.

3. The funds of the University are not sufficient to justify it in be-
stowing a portion of them on a work, however important and valuable
to the State, that is not legitimately a portion of its business.

The appropriation by the State of $3,000 annually for the geological
survey, pays no more than the salary of the principal and assistant
‘geologists; and the outfit and traveling expenses, &c., amounting to as
much more, have to be provided for out of the college funds. This is
unjust to the University, and the divided time of the State Geologist be-
tween the University and the field, operates injuriously both to the in-
terests of the University and the State. I would not be understood by
this, nor would the Board of Trustees, as casting any reflection upon
the learned gentleman who now fills the place of State Geologist, and
whom they and myself believe to be well and highly qualified for the
duties of that station, nor would we have it understood, and the Boar-]
of Trustees would not, that we detract in the slightest measure from the
great interest and importance to the State of having a geological survey
thoroughly and efficiently presecuted. The object is to place it in the
hands of the State and under the direction of her authority, where it
properly belongs, and to have it vigorously prosecuted to completion at
the earliest day. I therefore recommend to the Legislature, to place it
in this position and to provide the means necessary to accomplish this
object. It is believed that an appropriation annually, for three years of
$6,000, will be sufficient to complete the entire work within that period.

The report of Professor Harper, herewith submitted, contains. much
valuable information—shows a high degree of scientific attainment on
his part, and gives evidence that when the work is completed, it will be
one of great value to the public. The present report is only preliminary
and partial and is not designed for publication at this time, but is to be
embodied and published in the general report when completed.”

The suggestion of the governor was not, however, favora-
bly acted upon by the legislature; the matter was left in statu
quo, but with the understanding that a vigorous prosecution
of the work should pave the way to more satisfactory legisla-
tion at a succeeding session.

After passing the winter at Oxford in the arrangement of
the collections and preparations for analytical work, | pro-
ceeded in April, 1856, to make a detailed exploration of the
northeastern portion of the state, where the geological struc-
ture seemed most complex and varied. In the course of this
expedition, made with the same outfit that had served the
year before, I determined the character, stratigraphical rela-
tions and limits of the carboniferous, cretaceous and tertiary

292 The American Geologist. Max. derae

beds of that part of the state, making extended collections es-
pecially of what was afterwards designated as the Ripley
Group of the cretaceous by Conrad.*

I also investigated closely the features and geological rela-
tions of the “Orange Sand” (now better known as the La-
fayette formation of the Southwest), showing its derivation
partly from northern sources, partly from the underlying for-
mations of which it contains the fossils; distinctly characteriz-
ing it as a quarternary deposit.

It having become clearly apparent to me by this time that
the survey would never maintain itself in public esteem on the
basis of mineral discoveries, and that it must seek its main
support in what services it might render to agriculture, I
made a point of paying close attention to and recording the
surface features,t vegetation, soils, the quality and supply of
water, and especially the marls, which I found to occur in
large supply and great variety. I also made a collection of
plants, which, although omitted from the subjects mentioned
in the act ¢reating the survey, I perceived was essential to-
ward the characterization of soils. In the prosecution cf
these studies, the close connection between the surface vege-
tation and the underlying formations became so striking, that
I soon largely availed myself of the former in tracing out the
limits of adjacent formations, in searching for outcrops, etc.

I also, by current inquiry among the inhabitants, ascer-
tained all that was known regarding the peculiarities, merits
and demerits of the several regions or soils, from an agricul-
tural point of view, and studied their practice and its results
on the several soils and crops.

During the latter part of the season of 1856, I extended

*A collection of fossils from these beds was sent to Conrad by: Dr. Spill-
man, of Columbus, to whom I had given a list of good fossiliferous localities
of that group, of which he promptly availed himself. The same season
(1856) in Conrad’s published description of these fossils (Jour. Acad. Sci.,
Philadelphia, Vol. IV, N. S., pp. 275 to 291.) Dr. Spillman is erroneously
eredited with being the discoverer of the Ripley beds. My original collection,
containing a number of species still undescribed, was unfortunately never
seen by Conrad, with whom I twice made arrangements for a protracted visit
to Oxford for the purpose of studying the collections of the survey. His
feeble health and subsequent death prevented the carrying-out of this pro-
gram.

7No instrumental topographical work was ever done in connection with
the Mississippi survey, partly because it was not provided for by law, partly
because the continually recurring violent barometric changes during the work-
ing season rendered the use of the aneroid, so useful elsewhere, very unsat-
isfactory. The railroad leyelings then available were, however, fully and
extensively used by me, an. were excluded from the report of 1860, simply
by the absolute need of brevity for the sake of reducing the expense of pun-
ication.

The Mississippi Survey.—Hilgard. 203

the detailed survey of the cretaceous area as far south as Co-
lumbus ; and thence, as the beginning of the rainy season ren-
dered farther field work unprofitable, I drove across the coun-
try to Tuskaloosa, Ala., in order to compare notes and con- '
sult with Tuomey, then state geologist of Alabama, and to
gain an insight into the works of reference for cretaceous and
tertiary paleontology ; of which not one had been provided by
Harper, although at his request the costly illustrated works of
Goldfuss, d’Ordigny and others, treating of European paleon-
tology, had been placed in the University library. As these
works did not furnish us with the means of identifying the
fossils of the Mississippi formations, Harper seriously pro-
posed to confer on them all, names of our own making, irre-
spective of previous observers. Upon my suggestion that this
was rather an unusual mode of proceeding and might at the
very least give rise to some confusion, he agreed that I might
try to obtain from Tuomey the necessary information as to
the possibility of procuring the existing American works, of
which he, however, expressed a very low opinion. Hence my
excursion to Tuskaloosa, in which I reaped the benefit of
Tuomey’s previous labors, and came to an understanding with
him in respect to the subdivisions of the cretaceous, recog-
nized by him. It happened that he had just returned from an
excursion to the (Ripley) cretaceous area of Chunnenugga
Ridge, which was entirely new to him, and the relations of
which to the other groups he had not yet made out. Recog-
nizing the characteristic fossils and marlstones of the Ripley
group, I was enabled to clear up that point as well as the re-
lations of the “Tombigby Sand” fossils (which had been sent
to him from Columbus by Dr. Spillman) to the “Rotten Lime-
stone,’ which we had thus far designated as “Upper,” but
agreed henceforth to consider as middle cretaceous. I then
learned for the first time that he had found fossils,—well pre-
served ammonites and several gasteropods, silicified, in the
lower cretaceous clays near Eutaw (or rather Finch’s Ferry),
Alabama ; and we agreed to designate this lower clayey stage,
which in Mississippi I had found entirely barren of fossils, as
the “Eutaw” group. Subsequently, prior publication gave
precedence to Safford’s name of ‘‘Coffee group” for the lower
clays, and similarly my “Tippah group” received from Conrad

294 The American Geologist. May, 1901.

the prior name of “Ripley” for the uppermost cretaceous.
Tuomey had at that time a portion of his second report in
manuscript; and as unfortunately he died six months after
our conference, after a protracted illness, that report, which
was posthumously edited by J. W. Mallet, does not show the
latest phase of Tuomey’s knowledge of the cretaceous stages.
As his collections were mostly destroyed during the war, it is
of interest to record here, from my personal observation, that
almost all the cretaceous fossils marked ‘‘Miss.” in list “A,”
p. 257, of that report, were from the “Tombigby Sand” and
the immediately overlying portion of the “Rotten Limestone.”
in Lowndes county, Miss.; the ‘Ammonites Binodosus,” re-
corded in the same list, from Eutaw, Ala., was considered by
him as a “leading fossil” of the lower cretaceous clays; the
specimens were all silicified and in excellent preservation.

As regards the tertiary formations, Tuomey was strongly
impressed with the fact that the older stages reappear above
the drainage level to the southward, after sinking out of view
at the St. Stephens bluff; and he suggested to me then that
what I subsequently named the “Grand Gulf rocks” might be
equivalents of the ‘“Burstone’’ sandstones of South Carolina.
So far as this point is concerned I was therefore strongly
impressed with the same ideas that have been so persistently
set forth by Otto Meyer. Having obtained from Tuomey
references to all publications then extant on the cretaceous
and tertiary of the south and west, I returned to Oxford in
November, across a country rendered almost impassable by
copious rains.

I found matters rapidly coming to a crisis at the Univer-
sity. Harper had been provided with a separate ambulance
outfit, and had taken the field for a few weeks during the sea-
son of 1856 in the northwestern counties ; but he seemed to be
unable to keep away from Oxford for any length of time. F'1-
nally, the dissatisfaction of the board of trustees with his per-
sonal acts, in relation both to the survey and to the University,
came to a head in November, 1856, when he was forced to re-
sign. I was continued as assistant, with compensation in-
creased to $1,500 per annum, and was for the time being
nlaced in charge of the survey, the office work of which I con-
tinued during the winter.

The Mississippi Survey.—Hilgard. 295

At the legislative session of 1856-’7, however, Harper, by
strenuous effort, procured the passage of an act entitled “An
Act to provide for the printing of the Second Annual Report
of the Agricultural and Geological Survey of the State, and
for other purposes,’ approved January 31, 1857. The sub-
stantial provisions of this act were, first, the complete separa-
tion of the survey from all connection with the State Univer-
_ sity; second, that the survey should be prosecuted to comple-
tion according to the provisions of the previous act, “by a state
geologist, to: be appointed by the governor, and to receive a
salary of two thousand dollars per annum, to be furnished
with such an outfit as may be necessary, to be provided under
the direction of the governor; he shall also keep an exact ac-
count of his expenses in making said survey, and submit the
same to the examination of the governor, who shall issue his
requisition upon the treasury for the amount, provided the
sum shall not exceed one thousand dollars per annum.” An
appropriation of twelve hundred dollars was also made for the
purchase of chemical apparatus for making analyses, and the
state geologist was authorized (as a measure of economy sug-
gested by himself), to “occupy as a laboratory the two front
rooms in the second story of the penitentiary building; and
he shall be allowed the assistance of one convict, to be named
by the inspectors, to aid him in keeping his apparatus in good
order.’’ It was also ordered “that five thousand copies of Pro-
fessor Harper’s report be printed,” and thereafter distributed
in accordance with the provisions of the former act. The sum
of thirty-five hundred dollars was appropriated for this publi-
cation, and Harper entered upon the office on March 1, 1857,
but was voted compensation from the date of his resignation,
in November preceding. The only work performed by him
during his tenure of office under this act, was the writing and
publication of his report, which was done under his personal
supervision at New York, although, like the former report, ‘t
bears the imprint of the state printer at Jackson.

Of this report it need only be said that it is a literary, lin-
guistic and scientific curiosity, and probably unique in official
publications of its kind. It is the labored attempt of a sciolist
to show erudition, and to compass the impossible feat of in-
terpreting and discussing intelligently a considerable mass of

296 The American Geologist. baa tihites

observations mostly recorded by another working on a totally
different plan from himself. In making use of my field notes,
which of course passed into his hands, the facts as well as the
conclusions suffered such distortion that but for the introduc-
tion of all the figures and diagrams given in my manuscript,
I sould have been unable in many cases to recognize my own
work. It is thus that the “Orange Sand” becomes in his
hands “The Miocene Formation ;’ while what he saw of the
Port Hudson beds, as well as the quarternary gravels, are re-
ferred to the eocene. Shortly after the publication of the
book, I publicly disclaimed all responsibility for either facts
or conclusions pretended to be based upon my work, since, al-
though my name is nowhere mentioned in the volume, the in-
numerable errors would, in the course of time, be likely to be
laid at my door. The circulation of the report through the
state soon produced the inevitable result of discrediting its au-
thor to such extent that toward the end of the year 1857 he
was obliged to resign his office.

Shortly afterwards the appointment was tendered to me
(then acting as chemist to the Smithsonian Institution), and
accepted; and I entered upon its duties early in 1858. At
Jackson I found in the “two front rooms in the second story
of the penitentiary,’ under the charge of the convict assistant,
the outcome of the purchases made by Harper under the pro-
vision for the outfitting of an analytical laboratory.- It con-
sisted essentially of apparatus for elementary lectures in chem-
istry, and an expensive microscope; the analytical balance was
represented by a pair of apothecary’s scales, etc. Under au-
thority of the governor, a portion of the useless articles were
sold, and the proceeds applied to the purchase of necessaries
for analytical work, and under the same authority and by per-
mission of the Board of Trustees of the State University, I
transferred the whole to a front room in the University build-
ing at Oxford, which I fitted up as a laboratory, at a personal
expense of $600, for the time being. By this evasion of the
law, framed under Harper’s auspices (which was mandatory
only in respect to the location of the “office,” but not of the la-
boratory), the survey was again practically restored to its ori-
ginal connection with the University, without which the work
could not be successfully carried on under so small an appro-
priation.

The Mississippi Survey.—Hilgard. 297

I took the field again in April, with the same outfit, an am-
bulance with two mules and a negro driver, and starting at
the Ripley cretaceous, I devoted the season to the verification
ot a full section across the tertiary area, from north to south;
including also the detailed examination of the fossiliferous lo-
calities of the “Jackson” and “Vicksburg” stages in their most
characteristic development. Contrary to my first impressions,
I found the Vicksburg beds everywhere along their southern
limit of outcrops, dipping southward wnder the lignito-gyp-
seous and sandstone strata of the “Grand Gulf” group, which
rise abruptly and sometimes in steep escarpments from the
low rolling or prairie country of the Vicksburg area; and be-
ing thus led to consider the Grand Gulf rocks as belonging to
a miocene or possibly pleiocene epoch, I devoted considerable
time to the study of its features and to the search for fossils.
That this search was unavailing so far as the finding of defin-
ite animal forms is concerned, and that a subsequent continu-
ation of the search over the rest of its area in Mississippi and
Louisiana has led to no better results, I have stated and dis-
cussed in later publications.* ‘

The fundamental fact of the infra-position of the Vicks-
burg beds to those of the Grand Gulf group that has been

- called in question by Otto Meyer, can easily be verified by any
one understanding the logic of stratigraphicai and hypsometri-
cal facts in numerous localities along the belt of contact. I
mention especially the outcrops at Mississippi Springs on
Pearl river below Byram; on Richland creek, Rankin county ;
on the Brandon and Byram road; north of Raleigh, Smith
county, and at numerous other points, both in Mississippi and
Louisiana. No other interpretation of the stratigraphical
facts is possible in a region where disturbances (apart from
small local faults), are unknown, and where the broad facts
are identical from the Chickasawhay to the Sabine.

In passing through the state I became painfully conscious
of the fact that the survey had become extremely unpopular,
as a consequence of Harper’s incumbency and report; so much
so that it was often very difficult to obtain information, or
even civil answers to inquiries. I felt that it would be neces-

_ *See my Mississippi Report of 1860, p. 147. Am. Jour. Sci., 1887; Ibid.,
Nov., 1869; Ibid., Dec., 1871; Ibid., July, 1881; also Smith. Contr. Sci.
ly Memoir, No. 248.

298 The American Geologist. May, 2a

sary to throw off, and purge myself completely, of the obnox-
ious antecedents, if the survey appropriation was to be sus-
tained at the coming session of the legislature. I therefore,
after consulting with Governor McWillie, wrote a short Re-
port upon the Condition of the Geological and Agricultural
Survey of the State of Mississippi, of 22 pages, 8vo., which
was printed by executive order and circulated prior to the
session of the legislature in the winter of 1858-’9. In this re-
port I discussed, first, the need and advantages of a thorough
geological and agricultural survey of the state; recited the
causes of the slow progress and failure to satisfy the public,
chief among which were inadequate appropriations and the
incompetency of the late incumbent; also gave examples of
what had been done in the matter in other states, and closed
with a recommendation for the repeal of the law locating the
headquarters of the survey in the state penitentiary, and for
the restoration of the geological assistantship, in connection
with a more reasonably adequate appropriation.

The storm, however, broke loose when the legislature as-
sembled. Those who had been instrumental in passing Har-
per’s bill in 1857, were now most eager to have the survey
“Wiped out” to allay their soreness. A special committee was
appointed to investigate the subject, and without even giving”
me a hearing, that committee promptly reported a “bill to abol-
ish the geological and agricultural survey of the state.” In pre-
senting this report the chairman inveighed fiercely against the
insolence exhibited in my report, above alluded to, and my at-
tempt to “coerce the legislature by forestalling public opinion.”
The report to abolish would undoubtedly have been promptly
adopted, but for my forcing a personal conference with the
chairman; in which I presented to him the documents in the
case, and exhorted him to abolish me, if he thought there was
cause, but not the survey, the revival of which would only be a
question of time. After this, the “bill to abolish” was not called
up, and the survey remained in statu quo during 1859.

The previous season’s work having settled conclusively the
succession of the several stages of the tertiary, and their promi-
nent stratigraphical, lithological and paleontological features,
I devoted the season of 1859 to the filling-in of details. I went
more leisurely over the ground intended to have been covered

The Mississippi Survey.—Hlilgard. 299

by the previous joint expedition of Harper and myself in 1855,
viz: from the southern border of the cretaceous area, near Co-
lumbus, down the Chickasawhay and Pascagoula valleys to the
sea coast; along the coast to Pearl river, up that river to Co-
lumbia, Marion county, and thence across to the Mississippi;
thence northward along the eastern border of the loess region
to the belt of marine tertiary, which I also examined more in
detail between Jackson and Vicksburg. All these observations
only served to confirm and complete my previous conclusions ;
the only new point being the examination of the perplexing
aspects under which the “Port Hudson group” (then provision-
ally designated by me as ‘“‘Coast Pliocene’), appears on the
shores of Mississippi Sound. I was not long in rejecting all
ideas of its direct connection with the Grand Gulf strata; but
its true character of a littoral member of the deposits of the
loess epoch did not become apparent to me until, later on, I had
the opportunity of studying, connectedly, the geology of south-
ern Louisiana.”

Returning from the field somewhat earlier than usual I be-
gan the arrangement of materials for a report, to be presented
at the legislative session of 1859-’60, with a view to its publica-
tion and the procurement of a better endowment for the survey.

As an earnest of the work done, I put up a collection of
soils and marls, gathered during the three years’ work, and had
it on exhibition at the State Fair held at Jackson in November.
It excited a good deal of attention and newspaper comment,
and gave a favorable turn to public opinion, previously aroused
by frequent communications of results made by me to agricul-
tural and other papers of the state. Outside of the fair week
I carried on the work of analysis and writing, simultaneously
and unremittingly; the only assistance received being that of
the legislature convened in December, 1859. But there was
cataloguing of the tertiary fossils by Prof. W. D. Moore, then
holding the chair of English literature at the University of
Mississippi. The manuscript was not nearly completed when
enough to satisfy a special committee that it should be printed,
and-that the working facilities should be enlarged.

The bill reported by that committee and afterwards passed
with little difficulty by the legislature, makes no radical changes

*See Smith’s Contra. Sci., Memoir No. 248, above referred to.

300 The American Geologist. May tee:

in the previous act defining the objects of the survey; but pro-
vides for the appointment otf an assistant geologist at a salary
of $1,500; enlarging the limits of the annual “‘expenses neces-
sarily incurred in fitting up a chemical laboratory,” and repeal-
ing the provision for keeping an office at Jackson; permitting
the alternative of having it at Oxford. An appropriation of
three thousand five hundred dollars is made for printing the
report, “with such diagrams and maps as the governor shall
deem necessary for its illustration; and it is hereby especially
enjoined upon his excellency, in the publication of said book,
to have the same performed at the South, if the same can be
done at an advance of ten per cent. upon the cost of its publica-
tion at the North.”

The latter clause was a charactertistic sign of the times. The
act was approved by the governor, February 10, 1860. It was
soon and easily ascertained that the five thousand copies of the
volume could not be printed anywhere at the South at an ad-
vance of ten per cent. on New York prices; but Governor Pet-
tus declared that he would not allow it to go North under any
circumstances, even if it had to remain unprinted. Esti-
mates prepared by Mr. E. Barksdale, the state printer, showed
that to do the work in his office would cost over $4,000, at the
lowest estimate I placed upon the uncompleted manuscript.
Finally, Mr. Barksdale proposed that if I should be personally
responsible for $250 of the excess of cost over the amount al-
lowed by the state, he would cover the rest; and I accepted the
proposition. The governor relented so far as to allow the map,
which could not be furnished by any Southern establishment, to
be prepared by the Coltons, at New York; the other plates were
prepared at New Orleans. The printing was begun at Jackson
in May, 1860; the latter parts of the report were largely written
while the first portions were passing through the press. But
several forms were not yet in print when in August imperative
matters called me to Europe, and Prof. W. D. Moore, who had
previously aided me in working up the lists of fossils, under-
took to see the remainder of the work through the press. Hence
there remain in the latter part of the book a number of uncor-
rected errata, of which none, however, are of material conse-
quence.

In this report (which except as otherwise credited in the

a eee

The Mississippi Survey.—Hilgard. 301.

text, represents my personal field, office and laboratory work
during four years), I undertook to separate as far as possible,
the purely scientific part from that bearing directly upon prac-
tical points, in order to render the latter acessible to unsci-
entific readers as the nature of the case permitted ; while at the
same time giving scientific discussion full swing in its proper
place. This was the more necessary, as my predecessor’s re-
ports had been sharply criticised in this respect ; and I think the
result has justified my judgment in the premises. The volume
is thus divided nearly evenly between a “geological” and “agri-
cultural” portion; the former giving under the special heading
of “useful materials” the technically important features of each
formation, after its geological characters have been discussed.
In the agricultural portion, it seemed needful at the time fo
give, by way of introduction, a brief discussion of the princi-
ples of agricultural chemistry, then but little understood by the
general public; and, accordingly, fifty pages are given to this
subject and are discussed with reference to the agricultural
practice of the State. In the special or descriptive portion of
the agricultural report, the State is divided into “‘regions” char-
acterized by more or less uniformity of soil and surface fea-
tures; and each is considered in detail with respect to all nat-
ural features bearing on agricultural pursuits; special atten-
tion being given to the nature of the soils, as shown by their
vegetation and analysis. In the latter respect I departed point-
edly from the then prevailing opinions, by which soil analysis
was held to be practically useless. My exploration of the State
had shown me such intimate connection between the natural
vegetation and the varying chemical nature of the underlying
strata that have contributed to soil formation, as to greatly en-
courage the belief that definite results could be eliminated from
the discussion of a considerable number of analyses, of soils
carefully observed and classified with respect both to their ori-
gin and their natural vegetation, and a comparison of these
data with the results of cultivation; and that thus it would be-
come possible, after all, to do what Liebig originally expected
could be done, viz: to predict measurably the behavior of soils
in cultivation from their chemical composition. To what ex-
tent this expectation has been fulfilled, is hardly apparent from
the very limited number of analyses which my unaided work

302 The American Geologist. GS, Se

was able to furnish for the report of 1860. But the lights then
obtained encouraged me to persevere in the same line of inves-
tigation, in the face of much adverse criticism, when wider op-
portunities presented themselves afterwards. By the aid of
these I think I may fairly claim, that the right of soil analysis to
be considered as an essential and often decisive factor in the
a priori estimation of the cultural value of virgin soils, has been
well established alongside of the limitations imposed by phys-
ical and climatic conditions, and by previous intervention of
culture. *

With the recognition of these facts, the importance of agri-
cultural surveys to the population of especially the newer states
and territories becomes sufficiently obvious to command at least
the same attention as those investigations directed specially to
the recognition of the geological and mineral resources of the
same regions; and the “‘classification of lands,” provided for
under the law creating the United States Geological Survey,
assumes a new and more pressing significance. Even apart
from any special investigations of soil composition, the right
of the agricultural interests to at least a good, intelligent and
intelligible description of the surface features of a region,
given with respect to its agricultural capabilities and its attrac-
tions for settlers, can hardly be denied. With the additional
possibilities opened by the intelligent application of soil investi-
gation, there is no excuse for the neglect, sometimes almost ab-
solute, with which this branch of the public surveys has thus
far mostly been treated by those charged with their execution.

Dr. David Dale Owen was, among the older American geol-
ogists, the one who most steadily kept the agricultural interests
in view, and gave them prominence in his researches and re-
ports. While my personal intercourse with him predisposed
me to follow his example in this respect, my further experience
has only served to strengthen my conviction that a reasonable
proportion of attention given to agricultural work would effect-
ually smooth the path of our state surveys, whose fate is for-
ever trembling in the balance at each reassembling of the legis-
lative bodies upon which their continued endowment depends,
and by whose country members their utility is constantly called

*For a more extended exemplification and discussion of the nature and
utility of such work, see the ‘‘Report on Cotton Production in the United
States” Vols. 5 and 6 of the Reports of the 10th Census; also Am. Jour. Nei.,
Dec.. 18T2, p. 434: Tbid., Sept., p. 183.

The Mississippi Survey.—Hilgard. 303

in question. No such question was raised in Mississippi after
the publication of my report of 1860; and the legislative appro-
priations for substantially similar work done by me on behalf
of agriculture have since been liberally maintained in Califor-
nia, despite the conspicuous disfavor with which the geological
survey of that state has for many years past been regarded
by the public. Had that survey been adapted to the legitimate
needs of the state, by proper diligence in the pursuit of its agri-
cultural side, the discontinuance of the work could never have
been carried through the legislature.

As a striking exemplification of the change wrought in pub-
lic sentiment by the energetic prosecution of agricultural sur-
vey work, I may quote the action taken at the called session of
the legislature of Missisippi in August, 1861. Under the terri-
ble stress brought to bear on the state even then by the im-
pending conflict, it would have been natural to expect the com-
plete extinction of the appropriation for the survey work. In-
stead of this, an act was passed suspending the appropriation
for the geological survey “until the close of the war, and for
twelve months thereafter ; except the sum of $1,250 per annum,
which shall be applied to the payment of the salary of the state
geologist, and the purchase of such chemicals as may be neces-
sary to carry on the analysis of soils, minerals and mineral
waters and to enable him to preserve the apparatus, analyses
and other property of the state connected with said survey.”
This appropriation was actually maintained during the entire
struggle of the confederacy; and so far as the vicissitudes of
war permitted, the chemical work (and even some field work)
was continued by me during the same time. The scarcity of
salt suggested a utilization of some of the saline waters and
efflorescences so common in the southern part of the state, and
some forty (unpublished) analyses of such saline mixtures are
on record. I made an official report on the subject to Govern-
or Pettus, dated June 9, 1862. I also made a special explora-
tion on the several limestone caves of the state, with a view ‘to
the discovery of nitrous earths; but from the fact that these
caves are all traversed by lively streams, I found nowhere a
sufficient accumulation of nitrates to render exploration useful.

Soon after the beginning of active hostilities in Tennessee,
the University faculty having been dissolved, I was detailed by

304 The American Geologist. Say

the governor, as commander of the state militia, to take charge
of the state property at the University during the war ; and this,
as well as a subsequent. appointment by the confederate au-
thorities as an agent of the “Nitre Bureau,” prevented my be-
ing called into active service; except on the occasion of the
siege of Vicksburg, when, toward the end of that memorable
epoch, I was ordered to erect “calcium lights” on the bluffs
above the city, for the illumination of the Federal gunboats
when attempting to run the gauntlet of the batteries. The dif-
ficulties of construction and procuring of the necessary mater-
ials delayed the completion of the arrangements, so that on the
occasion of the final passage of the fleet no adequate light could
be given. From a hospital at Jackson, where I was a patient
at the time of its first capture, | soon afterwards made my way
to my post at Oxford, where I remained on duty during the
rest of the war. This duty was oftentimes a very arduous one,
Oxford being then within the “belt of desolation” between the
two armies, which swept back and forth over it. The survey
collections had several very narrow escapes from destruction
when the buildings were hastily occupied for hospital pur-
poses; they were several times transferred on hospital cots
from one building to another, but finally escaped without any
material injury. Not so the collections at the capitol at Jack-
son, where the shelves and cases seem to have been swept with
the butts of muskets, and the floor was strewn with broken spe-
cimens and shattered glass jars. About one-third of the collec-
tions stored there was entirely ruined, and of the remainder
nearly all the labels were lost.

On my return from Europe in November, 1860, I found my |
report in print, and shortly afterwards it was shipped to St.
Louis for binding. The political events which soon afterward
convulsed the country, prevented the return of the bound edi-
tion to Mississippi. It remained warehoused in the binder’s
hands during the entire war between the states, and it was not
until 1865 that measures were taken for its recovery. The war
and the “‘twelve months thereafter” having expired, the survey
was revived ipso facto on the basis of the act of 1860; and I
found the state printer of that time, Mr. E. Barksdale, deter-
mined to carry out to the letter his agreement in respect to the
publication of the report; thus likewise reviving my obligation

The Mississippi Survey.—Hilgard. 305

to contribute $250 toward the payment of its cost, which under
the gonditions then existing was a heavy tax. The edition was
received at Jackson early in 1866, and thence distributed ac-
cording to law.

The mule team of the survey had been sold by authority
from the governor, soon after the passage of the act of sus- .
pension. There being no legal mode of turning the proceeds
into the state treasury, they remained in my custody in the form
of “Cotton Money” (notes issued by the state upon “cotton
pledged” for their redemption) during the war; and as at its
end these notes had become worthless, the survey was left with-
out means for repurchase. Subsequently, however, a suitable
team was procured out of the appropriations for current ex-
penditures.

Dr. George Little, formerly professor of natural sciences at
Oakland College, near Rodney, Miss., was appointed assistant
geologist in July, 1866, and shortly thereafter took the field
for detailed exploration of the loess region from Rodney to its
fartherest point in Louisiana; the special object being to ascer-
tain its relation to the “Coast Pliocene” or Port Hudson beds
on the one hand, and to the southern equivalent of the “Yellow
Loam” of Mississippi and Tennessee on the other. The gener-
al results of this exploration are briefly stated in Memoir No.
248 ofthe Smithsonian Contributions, p. 4, viz: That the loess
material gradually changes toward that of a non-calcareous
and non-fossiliferous hardpan or indurated loam, from a point
about eight miles below the Louisiana line, and seems also to
thin out. No detailed report of field notes of this trip are on
record.

In view of the difficulties and insecurity besetting the office
of state geologist under the regime then existing in the state
of Mississippi, in October, 1866, I accepted permanently the
chair of chemistry at the University; and Dr. Little was then,
upon my recommendation, appointed state geologist. He took
the field in autumn of 1867, in order to re-explore the section
of the tertiary strata afforded by the Chickasawhay river, be-
tween Enterprise and Winchester. He descended the stream
in a canoe, making numerous portages over shallow stretches.
The result of this re-examination was simply a confirmation
of the observations previously made by myself, going by land,

306 The American Geologist. May, Aue

in 1859. Of this exploration, also, no detailed record or re-
port is on file.

No field work was done by Dr. Little in 1868, partly be
cause by consent of the governor he was acting as professor of
geology and mineralogy at the University in addition to the
survey work in the laboratory and collection rooms. In Oc-
tober, 1870, however, he definitely resigned the state geologist-
ship for the professorship of geology and natural history in the
University, and in order to prevent the survey from being
either abolished or falling into the wrong hands, I again as-
sumed its direction without additional compensation; it being
understood that I should be under no obligation to take the
field personally. In November, 1868, the assistantship had
been most fortunately filled by the appointment of Dr. Eugene
A. Smith, of Alabama, then just returned from his studies in
Europe. Dr. Smith took hold of the work with his character-
istic energy, although the first work in order was not of the
most interesting character; namely, the farther prosecution of
the analyses of soils and marls selected so as to cover as nearly
as possible all parts of the state. This work was carried on
by him through the year 1869 and a portion of 1870. In Sep-
tember of that year he took the field, with the usual outfit of a
two-mule ambulance and driver. There were then two regions
in the state that had not been at all satisfactorily explored: one
the belt northward of the Jackson area, of which only the por-
tions lying in Neshoba and Lauderdale counties on the eastern
border of the state, and a small area in Attala county, near the
Central railroad, had been somewhat minutely examined by
me. This being the connecting link between the “northern
lignitic’ and calcareous marine stages, its examination was of
special interest, but at the same time a difficult task on account
of the extreme variability of its materials and fossils, and the
scarcity of outcrops. The other comparatively unknown re-
gion was the great ““Yazoo bottom,” the geological exploration
of which had become of especial interest in connection with
the question of the age of the formation of the gulf coast and
delta.

While the Bottom region was to be the chief objective point
of the first expedition, Dr. Smith availed himself of the oppor-
tunity of observing a section across the older tertiary in pass-

The Mississippi Survey.—Hilgard. 307

ing from Oxford to Yazoo City via the Pontotoc, “Flatwoods,”
Kosciusko and Jackson.

He then descended into the Yazoo bottom and traversed it,
zigzagging from the river to the bluff from near Vicksburg to
its head near Memphis. In this laborious and insalubrious
trip he studied carefully both the surface features of the
great alluvial plain, and the geological features of the deposits
that form its substrata. A summary report of this impor-
tant exploration was given by him at the Indianapolis meet-
ing of the A. A. A. S., and was published in the volume of
Proceedings of 1871, p. 252. The outcome of these observa-
tions is there summarily stated to have been that “the true river
deposits, of any considerable thickness, are mostly confined to
narrow strips of land lying on both sides of the Mississippi
and of the bayous and creeks, and to ancient channels since fill-
ed up; while a large proportion of the superficial area of the
bottom, including some of the most fertile lands, is derived
from the clays of older formations into which these beds have
been excavated.”’ The equivalence of this older clay formation
with that of the Port Hudson profile, already suggested by me,
was thus fully verified.

Returning to Oxford early in December, Dr. Smith carried
on the chemical work until the end of May, 1871, when he took
the field again in order to trace across the state the “Siliceous
Claiborne” belt, referred to. His route lay from Leake county
southeastward to the Alabama line, along the northern contact
of the problematic “Red Hills” and yellow standstones with the
lignitic formation; then westward again in the more southerly
portion of the belt, to the border of the Yazoo bottom (the
“Mississippi bluff”). In this trip he traced the connection and
established the equivalence of the ferruginous formation as a
local feature, with the sandstones of Neshoba and Newton
counties; which connect unequivocally with the characteristic
“burstones” of Lauderdale.* The beds of the Jackson group
were then traced by him, down the edge of the bluff to
Yazoo City and Vicksburg, forming the third complete section
across the eocene observed in Mississippi.

*The more extended development of the ferruginous feature ih northern
Louisiana was afterwards observed and described by myself. Am. Jour.
Sci., Nov., 1869, p. 341: Supplementary and final report of a geological re-
connoisance of Louisiana, p. 22. Also Rep. on the cotton production and
-agricultural features of Louisiana, in Report of the 10th Census U. S8., Vol.
‘By Dp. Li2;, 1s2.

308 The American Geologist. Mes aoe

In September, 1871, Dr. Smith resigned the assistantship to
take the chair of geology and mineralogy in the University of
Alabama, with which, through his efforts, the state geologist-
ship of that state was afterward connected. .

His successor in the assistantship of the Mississippi survey
was Mr. R. H. Loughridge,* of Texas, who had for some time
previously acted as my assistant in the chemical laboratory, and
subsequently as instructor in general chemistry. Mr. Lough-
ridge prosecuted the chemical work of the survey during a
part of the year 1872, and was preparing for the elaboration
of another report covering the work done since the publication
of the report of 1860; when by an arbitrary ruling of the state
auditor of public accounts the survey appropriation was with-
held; and thus in the autumn of 1872 the work was peremptori-
ly stopped.

It has not been revived since, although so far as | am aware
the act of 1860 has never been legally rescinded. No pro-

vision for the publication of the unpublished results has ever

been made by the state; the records and collections of the sur-
vey remain in the custody of the University of Mississippi, and
were left by me fully labeled as to locality and time of collec-
tion, with reference to the field notes, and to the name or desig-

nation under which the specimens of fossils appeared in my re-

port of 1860.
When I took charge of the Tenth Census report on cotton

production, and at my suggestion it was determined by Super-

intendent Walker that agricultural descriptions of the cotton

states should be embodied in the report, I requested of Presi-
dent A. P. Stewart, of the University of Mississippi, permis-
sion to use the records of the survey in the elaboration of the

report on that state. Permission was promptly given and the

papers forwarded to Berkeley, Calif.; and they were used by

me as intended, in the composition of the monograph on the ag--
ricultural features and cotton production of Mississippi, which
forms part of Volume 5 of the Census Reports for 1880. This
paper embraces 164 quarto pages, and is accompanied by a col-

*Mr. Loughridge subsequently received from the University.of Mississippi
the degree of Ph. D., and served for several years as assistant to Dr. Little
in the geological survey of Georgia. Subsequently, acting under my direc-
tion as special agent of the 10th Census, he made a reconnoissance of Texas,
_ and wrote the monographs on that State, Arkansas, Indian Territory, Georgia’
and Mississippi for the report on Cotton Production. Later he served on the

Geol. survey of Ky., with Prof. Proctor; and is now connected with the:

Agr. College of California.

The Mississippi Survey.—Hulgard. 309

ored map of the state; showing the several soil regions, which
in this case largely coincide with the geological subdivisions
as given on the map accompanying the report of 1860. While
the surface features of the state are given very much in detail,
the geological description is considerably condensed, into one
and a quarter pages; since greater minuteness of description
would have lain outside of the objects of the report. Hence,
' except as casually mentioned in connection with the surfaces,
the geological observations made by Dr. Smith in 1870 and
1871°remain unpublished, save as regards the abstract of his
observations in the Yazoo bottom, given in the paper referred
to before.

A revised edition of the report of 1860 would, without addi-
tional field work, form a pretty complete account of the geolog-
ical and agricultural features of the state.

BIBLIOGRAPHICAL NOTE.
Official publications of the survey of Mississippi.

1. Report on the Agriculture and Geology of Mississippi; embracing
a sketch of the Social and Natural History of the State, by B. L. C.
Wailes, Geologist of Mississippi, published by order of the Legislature.
E. Barksdale, State Printer, 1854. 391 pp. 8 vo., with map and 17 plates.

2. Preliminary report on the Geology and Agriculture of the State of
Mississippi, by L. Harper, LL. D., State Geologist of Mississippi. By
order of the Legislature of Mississippi. E. Barksdale, State Printer,
Jackson, 1857. 362 pp., 8 vo., with map, 52 figures in the text and seven
special maps and plate.

3. Report on the Geological and Agricultural Survey of the State of
Mississippi, by Eugene W. Hilgard, State Geologist, Jackson, Missis-
sippi. Steam Power Press Print, 1858. 22 pp., 8 vo. (printed by order
of the Governor).

4. Report on the Geology and Agriculture of the State of Missis-
sippi, by Eugene W. Hilgard, Ph. D., State Geologist, printed by order
of the Legislature. E. Barksdale, State Printer, Jackson, Mississippi,
1860. 417 pp., 8 vo., map, two plates of geological sections and 5 dia-
grams printed in the text.

5. Report to Governor John J. Pettus, on the Resources of the State
of Mississippi for the Manufacture of Salt. About 4 pp. octavo, but
published only in the newspapers of the State at the time. Dated Ox-
ford, June 9, 1862.

6. Circular Announcing the Resumption of the Geological and Agri-
cultural Survey of Mississippi, after the Cessation of the War. About
4 pp. 8 vo. Sent in two column open sheets to the officials and news-
paper press of the State. Dated Oxford, July, 1866.

310 The American Geologist. May. ten

Lists of papers relating to the geology of the southwestern States,
published by E. W. Hilgard, and based upon the geological surveys of
Mississippi and Louisiana.

1. The Quarternary Formations of the State of Mississippi. Am
Jour. Sci., May, 1866, 15 pp.

2. Remarks on the New Division of the Eocene, or Shell Bluff

Group, Proposed by Mr. Conrad. Am. Jour. Sci., July 1866, 4 pp.

3. Remarks on the Drift of the Western and Southern States, and
its Relation to the Glacier and Iceberg Theories. Am. Jour. Sci. Nov., - ;

5 pp. .
| 4 4. On the Tertiary Formations of Mississippi and Alabama. Am. |
BA saur Sci., Jan., 1867, 12 pp. ;

5. On the Geology of Lower Louisiana and the Rock Salt Deposit
of Petite, Anse Island. Am. Sci. Jour., Jan., 6 pp.

6. Preliminary Report to the New Orleans Academy of Sciences, of |
a Geological Reconnoissance of Louisiana. De Bows Review, Sept., ,
1869, I5 pp. |
7. Summary of Results of a Late Geological Reconnoissance of |
Louisiana. Am. Jour., Nov. 1869.

8. Report on the Geological Age of the Mississippi Delta. Rep. U. |
S. Engr. Dept. for 1870, 16 pp. .

9. On the Geology of the Delta, and the Mudlumps of the Passes
of the Mississippi. Am. Sci., 3d Series, Vol. I, 34 pp.

10. On the Geological History of the Gulf of Mexico. Proc. A. A.
A. S., Indianapolis, 1871. Am. Jour. Sci., Dec., 1871; Am. Naturalist .
Assn. Number, 1871.

11. Memoir on the Geology of Louisiana and the Rock Salt De- 1
posit of Petite, Anse Island. With maps and diagrams. Samuthsonian
Contributions to Knowledge, Memoir, No. 248. Lge. 4to 34 pp.

12. Some Points in the Geology of the Southwest. Am. Jour. Sci., .
Oct., 1872, 4. pp.

13. Supplementary and Final Report of a Geological Reconnotssance
of Louisiana; Made under the Auspices of the New Orleans Academy of
Sciences, and of the Bureau of Immigration of the State of Loutsiana, in
May and June, 1869. Picayune Job Print, 44 pp.

14. The Loess of Mississippi Valley and the Aeolian Hy pothesis.

WA Am. Jour., August, 1879, 8 pp.
I5. The Later Tertiary of the Gulf of Mexico. Am. Jour. Sci..
VA July, 1881, 8 pp., with colored map.

16. Report (by E. W. Hilgard and F. V. Hopkins) on the cae
made between Lake Borgne and the Mississippi River in 1874, at the
site proposed as an outlet for flood waters, Rep. U. S. Eng. Dept.,
1877, 49 pp.

17. Report (by E. W. Hilgard and F. V. Hopkins) on the borings
made on the Mississippi River, Memphis and Vicksburg, by the Miss.
River Commission. Rep. Miss. Riv. Comm'n. for 1883, p. 479, 18 pp.

The Mississippi Survey.—Hilgard. 311

18. Report on the Cotton production and Agricultural Features of

e State of Mississippi, 4to, 164 pp. with two maps. In Volume 5 of
UF sports of the Tenth Census.

19. Report on the Cotton Production and Agricultural Features of
the State of Louisiana, ato, 03 pp. and two maps. In Vol. 5 of the
Reports of the Tenth Census.

20. The Salines of Louisiana, U. S. Geol. Survey Report on the
Mineral Resources of the United States, 1883, p. 938, 8 pp.

21. The Old Tertiary of the Southwest. Am. Jour. Sci., October.

1885, 4 pp.
22. Orange Sand, Lagrange and Appomattox. Am. Geologist, Vol.

8, 1891, 2 pp.
23. The Age and Origin of the Lafayette Formation. Am. Jou,.
Science, May, 1892, 13 pp.

EDITORIAL COMMENT.

PLEISTOCENE GEOLOGY OF NORTHERN AND
CENTRAL ASIA.

Prof. George Frederick Wright, of Oberlin, Ohio, and his
son, Fred B. Wright, returned home about April Ist from'a
journey around the world, chiefly for geological observation,
which occupied somewhat more than a year. Their route was
by the Southern Pacific railway to California; thence to
Hawaii, Japan, and China, leaving the city of Peking after the
beginning of the Boxer massacres, from which they encounter-
ed much delay and peril, by the Siberian railway, passing lake
Baikal, and traveling the vast Russian empire to St. Peters-
burg; thence through the region of the Volga, and of the
Black and Caspian seas, to Armenia and Palestine; thence by
the Mediterranean and southern Europe to England; and
thence by Boston and New York to Oberlin. Attention was
given principally to Pleistocene geology, and to the absence or
presence of evidences. of glaciation. Professor Wright on
March 6th, at a meeting of the Geological society of London,
presented a paper on “Recent Geological Changes in Northern

‘and Central Asia,” from which the more important of his ob-
servations are summarized as follows in an abstract published
in the Proceedings of that society.

“The result of six weeks spent in Japan was to show that
there are no signs of general glaciation in Nippon or Yesso.

312 The American Geologist. May, Ser

Neither is there any sign of glaciation along the border of the
Mongolian plateau, where the general elevatior: is 5,000 ft. but
the whole region is covered with loess. This has usually ac-
cumulated like immense snow-drifts on the southeastern, or lee
side of the mountains, and in it houses and villages are exca-
vated. In the mountainous region, strata of gravel and pebbles
are so frequent in the loess that it is necessary to invoke both
wind and water in order to explain fully the origin of the de-
posit. At the present time the loess in the interior is being
washed away by the streams much faster than it is being de-
posited by the wind. The journey across Manchuria from

Port Arthur along the Loo-Ho and Sungari rivers was through .

valleys choked with alluvium, and there was no evidence that
the drainage of the Amur had ever been reversed by ice, like
that of the St. Lawrence; nor was there any other evidence
of glaciation. The lower course of the Amur indicates sub-
sidence. Again, there are no signs of glaciation on the Vitim
plateau.

‘Lake Baikal appears to be of recent origin; it is 4,500 feet
deep, and has not been filled by the great quantities of sedi-
ment brought down by the Selenga and other rivers. Although
glaciers could frequently be seen on the mountains which
border the Central Asiatic plateau on the northwest, there was
no evidence that the glaciers had ever deployed on the plain.
The loess region of Turkestan, and indeed the whole area from
the sea of Aral to the Black sea, appears to have been recently
elevated, in some places as much as 3,000 feet. Desiccation
took place at the same time, so that the larger lakes are only
brackish or still fresh. Direct evidence of this in the form of
deposits is given. The author thinks it likely that the absence
of glaciation in northern Asia may have been due to the rain-
lessness of the region, and that, while America was elevated,
Asia was depressed during the Glacial epoch.”

In connection with the discussion of this paper, Prof.
Wright disclaimed any intention to imply an eolian origin for
the loess of the Mississippi valley, but attributed its deposition
there to annual river floods, mostly of short duration, followed
generally during a greater part of each year by aerial ex-
posure of the flood plain, permitting it to be occupied by veg-
etation and land shells. Ww. U.

Review of Recent Geological Literature. 313

REVIEW OF RECENT GEOLOGICAL
LITERATURE.

Was Mount Royal an Active Volcano? By J. S. Bucuan, K. C., B.

C. L. Canadian Record of Science, Vol. VIII, No. 5, pp. 321, 328.)

It is well known that the broad and nearly level valley of the St.
Lawrence, which is underlain with paleozoic strata, has suffered enor-
mous denudation, unique evidence of which is furnished by the interest-
ing series of intrusive hills which crosses the valley from Montreal to
Shefford. These, owing to their greater resistance to erosion, stand
out in bold relief, rising to hights of seven hundred to twelve hundred
feet above the plain, while high up on their slopes, sedimentary frag-
ments are often found in situ, giving unmistakable evidence of the
once greater thickness of the sedimentary. deposits.

In the above mentioned paper, these and other phenomena are dis-
cussed in support of the hypothesis that Mount Royal is an uncov-
ered laccolite instead of a once active volcano. Mount Royal rises
seven hundred and forty-four feet above the St. Lawrence river at
Montreal and sedimentary patches occur on it nearly at the top. As
corroborative evidence the plutonic character of the igneous rocks
together with the absence of tuff or effusive material is cited, as well
as a slight uplift of the strata in some places.

Since the absence of any but deep-seated rocks seems to be suf-
ficiently accounted for by the extent of the erosion already referred to,
and as the uplifting of the strata is not very pronounced, Mr. Buchan
is probably prudent in expressing his conviction very reservedly.
The generally little disturbed position of the surrounding strata is
certainly unfavorable to the theory of a laccolitic structure, which
seems less likely to occur here than in the eastern part of the St.
Lawrence valley within the influence of the Appalachian uplift.

The Aen!
The Summary Report of the Geological Survey of Canada for the

Year 1900. (203 pages, 1901.)

In this report special prominence is given to the results of field-
work accomplished during the past summer, thus affording an early
publication of a preliminary kind for any new facts obtained, whether
of economic or scientific importance.

Thirteen parties were in the field for the greater part of the sum-
mer and carried on observations from the Yukon district and British
Columbia to Nova Scotia.

The report states that several mineral products have -been ob
tained and sent out as samples or. for examination by experts, among
which may be mentioned, amlar mica, or phlogopite, which was sent
to the director of the Scientific and Technical Department of the Im

314 The American Geologist: May, 1901.

perial Institute, London, and was pronounced by experts to be of ex-
ceptionally high value for electrical purposes. Molybdenite from Que-
bec and Ontario was tested in the laboratory of McGill university
and samples of auriferous black sands from the Atlin district were
also examined. These samples varied from 0.5 oz. gold per ton to
5.985 oz. gold per ton. Mention is made of the discovery of anthracite
coal in the region about the headwaters of the Sheena and Slikine
rivers. It is estimated there are 22,000,000,000 tons of possibly work-
able coal in the Crow’s Nest Pass coal fields. Coal has also been
found in the Klondike region but so far possesses only a medium eco-
nomic value.

Reference is made to the collection sent to the Paris exposition.
This collection weighed about 70 tons, and comprised over 1,200 sepa-
rate exhibits and was much larger than any shown by Canada at any
previous international exposition. The awards actually awarded to the
Canadian mineral exhibits comprise six grand prizes, ten gold medals,
eighteen silver medals, nine bronze medals and four honorable men-
tions.

The most important facts of economic value are contained in the
descriptions of the following: The placer mines (estimated.to pro-
duce over $16,000,000 this year), the lignite area and the White Horse
copper deposits in the Yukon district, the Atlin and West Kootenay
gold fields and the extensive coal area of the Crow’s Nest pass, in
British Columbia, the iron bearing rocks of the Michipicoten district
including the Helen mine, which from definite measurements con-
tains 26,000,000 tons of ore and possibly a much larger quantity; the
alluvial gold deposits of New Brunswick, and the extensive and im-
portant coal deposits of Springhill and Cape Breton in Nova Scotia.
A large amount of work was done by all the field parties in mapping
out the geological formations, and in making surveys and collecting
facts about the regions traversed so that the report contains valuable
information about the physiography and natural history of large areas
in the older provinces as well as in outlying districts including Great
Bear lake.

The work done in chemistry and mineralogy, mineral statistics, petro-
graphy, palaeontology and zoology, botany and mapping is fully set
forth by the gentlemen in charge of these branches. W. J. W.

Analysis of Emery from Virginia. By W. W. MItter, Jr. Am. Chem.

Jour., 22, 212-213.

The emery occurs in a heavy ledge near Whittle’s on the line of
the Southern railroad in Pittsylvania county. It is described as a black,
crystalline mass; magnetic; polar; with specific gravity 4.205; and
hardness, 8. The analysis shows :—alumina, 56.74; ferric oxide, 15.50;
ferrous oxide, 20.77; silica, 0.68; titanic oxide, 1.86; soda, 3.95. The
ferrous oxide in excess of that required to form magnetite, is supposed
to be present as hercynite, Fe Al,O,; and the soda is considered to take
‘the place of the ferrous oxide in forming additional hercynite, thus
greatly reducing the amount of alumina which can exist as corundum.

Review of Recent Geological Literature. 315:

The large amount of hercynite reduces the erosive power and makes
the mixture of no value as emery. W. 0: C.
On the Constitution of Barytocelestite. By C. W. Votney. J. Am.

Chem. Soc., 21, 386-388.

Although previous work had discredited the existence of a true
bariumstrontium sulphate, showing only barites containing a trace of
strontium or celestites containing a trace of barium, the author finds
this mineral from eastern Ontario to yield: BaSO., 30.850 and SrSO,
70.010. A previous analysis by the author had given: BaSOu, 39.850 and
SrSO,. 58.200. These results correspond very closely to the formulas
(BaSr:) (SOs)3 and (BaSr; SOs)4. These two types of. baryto-
celestites have distinct habits of crystallization which remain to be in-
vestigated. W. O..C
Examination of Sandstone from Augusta county, Virginia. By W. W.

Miter, Jr. Am. Chem. Jour., 22, 216-217.

This sandstone is a disintegrated quartzite, occurring in the vicinity of
Basic City, and found to be valuable for ballast and road metal. The
analysis shows large proportions of alumina and alkalies, indicating
partially kaolinized feldspar which is regarded as explaining the pack-
ing of the material in use. W. 0. C.
Analysis of Simithsonite front Arkansas. By W. W. Mritter, Jr. Am.

Chem. Jour., 22, 218-219.

The smithsonite from the Morning Star mine in Searcy county, is
the usual botryoidal variety, and encloses layers of zinc blende from
which, probably, it has been derived. The analysis shows it to be
nearly pure; but with a little cadmium, copper and iron replacing zinc.

WL Oe

Some Principles of Rock Analysis. By Wut.tam F. HILvepranp.

(Bull. No. 176, U. S. Geol. Surv.)

While this is primarily a description of the analytical methods fol-
lowed in making rock and mineral analyses by the chemists of the U.
S. Geol. Survey at the Washington laboratory, the author has included
so much that is valuable in the way of general discussion of the prob-
lems involved that the bulletin practically amounts to a very com-
plete treatise on the subject of rock analysis. Particular emphasis is
laid on the importance of thoroughness of analytic work, especially as
regards the detection and estimation of the rarer rock-forming elements.
The value of many of the older analyses was greatly lessened and
often wholly destroyed by failure in this respect, and many erroneous
conclusions concerning mineral composition resulted. The introduc-
tion of improved analytical methods has not only made greater accuracy
possible but has brought to light many interesting facts about the oc-
currence, relative distribution and associations of the rarer elements.
In the descriptive parts we find the methods of procedure which experi-
ence has shown to yield the most satisfactory results outlined in’ such a
manner as to be of service to any having occasion to make rock or min-
eral analyses. Alternate methods are also given in many instances and
their advantages and disadvantages considered. In a few cases ap-

319 The American Geologist. May err

paratus of especially desitable pattern have been figured in the text.
Chemists will find the parts devoted to the estimation of small quanti-
ties of the rarer rock-forming elements, titanium, zirconium, chromium,
vanadium, molybdenum, barium, and strontium of particular interest;
also those devoted to ferrous iron. The author finds in the strong re-
ducing action which sulphides even in small amounts have on ferric
salts, an explanation of the fact that terrous iron estimations by the
sealed tube method of Mitscherlick give higher results, as a rule, thaa
those optained by other methods, this difference becoming more marked
as the percentage of iron increases. All rocks contain sulphur, at
least in traces, and the more highly ferruginous ones not only com-
monly carry higher percentages of ferric iron, but considerable quanti-
ties of iron sulphides, conditions exactly calculated to produce the re-
sults obtained. During the heating of the rock powder with sulphuric
acid in the sealed tube the sulphur of the sulphides is oxidized to sul-
phuric acid at the expense of the ferric iron. In this way as little as
0.10% of sulphur increases the ferrous iron by an error of 1.35%. This
seems to furnish a correct and interesting explanation of a long un-
solved problem. The wide experience and established reputation of the
author make this carefully prepared bulletin a most valuable addition to
the literature of analytical chemistry and it will find wide use by geol-
ogists and petrographers interested in rock analysis. W. 0. C.

Analyses of Rocks, Laboratory of the U. S. Geological Survey. Tab-

ulated by F. W. Crarx. (Bull. No. 168, U. S. Geol. Sur.)

In this bulletin are tabulated the results of 1,404 analyses of rocks,
minerals, clays, etc., which have been made between the years 1880
and 1889, by the chemists connected with the U. S. Geological Survey.
The analyses are arranged in groups according to the geographical lo-
cation of their respective rocks, and with each one are such notes and
references as are necessary for the proper identification and study of
the rocks.. A table, showing the average composition of the earth’s
crust as calculated by F. W. Clark from some eight hundred carefully
selected rock analyses, is an interesting and valuable part of the intro-
duction. Every geologist will appreciate the high value of this bul-
letin. Wade
An Experimental Investigation into the Flow of Marble. By FRANK

Dawson ApaAmMs and JoHN THomas NicHotson. (Pil. Trans.

Roy. Soc. London, Vol. 195, pp. 363-401, pls. 22-25. 1901.)

The artificial production of structures found in nature is a depart-
ment of investigation capable of yielding data on many problems of a
theoretical nature. The folding and flowage of rocks in the deeper
part of the earth’s crust are commonly supposed to be due to the inter-
action of three factors ;—great pressure, high temperature, and perco-
lating water. In the experiments here described carrara marble is
placed in specially constructed cylinders and subjected to differential
pressure under varying conditions. Dry marble at ordinary tempera-
tures developed a cataclastic structure, exhibiting an anastomosing net-
work of calcite granules with marked shearing lines. Macroscopically

Review of Recent Geolo gical Literature. Z17

the marble thus treated assumed a chalky appearance, which was found
to be due to the destruction by polysynthetic twinning of the continuity
of the reflecting cleavage surfaces of calcite. Dry deformation at 400°C.
produced foliation without any trace of cataclastic structure. As in ice,
the higher temperature produced a greater plasticity of the grains and
hence the ability to flow around each other. The addition of perco-
lating: water made no difference in the resulting structure. The cata-
clastic structure was found to have weakened the crushing strength
ot the marble; foliation to have weakened it very slightly; but folia-
tion produced with the accompaniment of percolating water strength-
ened the stone.

These deformations are found to be similar to those produced upon
metals, and analogous structures are found in certain highly contorted
lmestones. It is interesting to note that the presence or absence of
water made no difference in the structure, but it is possible that the
pressure was so great as to mask or prevent the possible effects of
water. These experiments were admirably planned and executed, and
they throw a little light on the difficult problem of the conditions which
obtain in the deeper zones of the earth’s crust. I. H. 0.

The Physiography of clcadia. By Recinatp A. Dary. (Bull. Mus.

Comp. zool., Vol. XXXVIII. Geol. ser., Vol. V, No. 5, pp. 73-104,

It pls.)

This is the first coherent and serious presentation of the physio-
graphy of Nova Scotia and adjacent regions. One might wish that it
were based upon a longer field study than a few days by rail and boat;
but it is founded also upon an extensive knowledge of physiographic
forms, and a close study of such maps as have been available. Fur-
ther research will probably not alter the main thesis of the paper. It
will, however, fill in many gaps: for the present study is only in out-
line, and of necessity treats of the broader features of the country. It
is to be hoped that it will be followed by more detailed work in the
same area, and an extension to peripheral regions.

The country is divided into the southern plateau, the Cobequid pla-
teau, the New Brunswick highlands, and the Triassic lava plateau em-
bracing North Mountain, Digby Neck and Long Island—al! parts of a
well made peneplain of probable Cretaceous age; the Triassic lowlands,
of Tertiary age; and the Carboniferous lowlands, also of Tertiary age
as regards denudation. The denudation is thought to have been sub-
aérial, although other theories are carefully considered.

The southern plateau is composed of the metamorphic gold-bearing
series (Algonkian?) and Siluria and Devonian strata. The author
omits a series of Cambro-Silurian rocks which are found in the eastern
half of Nova Scotia. It is stated that each of these has been involved
in a late Devonian mountain building. As it seems to the reviewer,
field evidence has not yet shown that the Silurian and Devonian are
structural units with the gold series, or that the main mountain build-
ing was Devonian. On the contrary, before the end of the Devonian,
the auriferous veins had been injected into the lower member of the

318 The American Geologist. May, 30ers

series, the whole had been folded in two directions and extensively
faulted and eroded; and at some times before this, enormous masses
of granite had been intruded, cutting the veins and folds. These gran-
ites are not all of the same age, but range from pre-Silurian, when
some of it in the east probably cooled, to Devonian, which is the age
of the large mass in the western half of the province, if it be one in-
trusion as seems likely. It is probable that the mountain building was
pre-Silurian. Before lower Carboniferous times, three-fourths of the
whole gold series had been eroded from some regions.

Dr. Daly has done well to emphasize the real lack of mountainous
projections in this part of Nova Scotia. Transportation companies’
prospéctuses, with the too vivid descriptions of untrained travelers,
have given a prevailing impression of ruggedness where none exists.
For this there is excuse; but there is none for the statements on the
subject which have appeared in some geological articles. :

The structure and history of the Triassic area and the history of the
Bay of Fundy trough are reviewed at length, from the literature. The
main peneplain has been affected by two warps, one in the direction
about S. 30° E., east of Digby ; the second transverse to it, affecting the
western part. These are believed to have aided in the formation of
the Tertiary lowland on the Trias, by. reviving subaérial work. The
Carboniferous areas are referred to the same age as regards their de-
nudation, from similarity of hight and topographic form. The dates of
the two peneplains have been placed as Cretaceous and Tertiary, on

account of similarity with corresponding ones along our own Atlantic

coast. At the close of the paper, (p. 98), a table of homologous forms,
expressed in terms of history is presented, comparing New England
and Acadia; and the general resemblance is certainly striking.

Shore and stream development are not considered; but, especially
with no topographic maps for the area, this would require a large
amount of field work, and doubtless will be given to us in time. Cape
Breton is entirely left out of the problem; and perhaps this is well, for
it requires special study, being largely a topographic and geologic unit
of itself. It may be said, however, that it has had a somewhat similar
development in outline.

The gelatine plates are for the most part excellent, and give very
vividly, especially to one who knows the structure of the country, some
of the chief topographic phases. The map leaves something to be de-
sired, in that it is too light; and it might better have occupied the
whole page, the legend being placed on a separate sheet.

On the whole, any criticisms of this first study must be of a minor
nature; and we owe much to Dr. Daly for being the first to give us
an intelligent idea of the topographic development of a country hitherto
rather neglected. The recent tendency of American students to invade
Canada deserves a passing notice. Within a year, for instance, two
more studies, of a quite detailed nature, will be published from Har-
vard University, dealing with problems which, from the nature of the
work, have been largely overlooked by previous observers. jee Wwe

Review of Recent Geological Literature. 319

The Structural Relations of the Amygdaioidal Melaphyr in Brookline,
Newton, and Brighton, Mass. By H. T. Burr. (Bull. Mus. Comp.
Zool., vol. xxxviii. Geol. Ser., vol.-v., no. 2, pp. 53-69, 2 pls.)

In earlier years, the melaphyrs of the Boston basin have been con-
sidered as contemporaneous flows by some writers. The present paper
appears to prove beyond doubt that those of the western portion, in-
cluded in the above-mentioned territory, are entirely intrusive. We
have no fossiliferous horizon to use as a key to structure; and the
_ presence of contemporaneous flows would be welcome. Their proved
absence in the western areas removes that aid, as far as those areas
are concerned. Readers who are familiar with the geological literature
of the region know the general relations of the rocks as regards posi-
tion, and it is not necessary to state them here.

A word may not be out of place, concerning the methods used in
this study, which was an incidental one; for they illustrate the careful
approach which is now employed in the problems in this difficult field.
A detailed outcrop map was plotted on a very large scale, made possi-
ble by the aid of city engineers. This gave the exact location of every
exposure of melaphyr, and of the other rocks as well. Detailed obser-
vations were recorded for each outcrop, and specimens collected when
necessary, for petrographic work. The result appears in the character
of Mr. Burr’s paper, which is a mass of clearly presented evidence,
with the inevitable conclusions drawn from it. The former is so stated
that the precise outcrops are indicated, and one can without difficulty
prove the worth of the observations for himself. This is as it should
be.

The evidence is of three kinds: lack of melaphyr pebbles in the
overlying conglomerate, negative but confirmatory ; character of the up-
per contacts of the melaphyr; and structural relations. The summary
is worth giving in full. ‘“(1) The melaphyr, in the region discussed,
is intrusive in the sediments. (2) The melaphyr is not associated with
any definite horizon, and is therefore of no value as a guide to the in-
terpretation of the structure. The first conclusion depends upon the
following facts: 1. The conglomerate, associated with the melaphyr,
contains no fragments of it. 2. The contacts, wherever found, are ig-
neous in character. 3. The melaphyr is seen in contact with sediments,
varying from the coarsest of the conglomerates to the finest of slate.
4. The distribution of the melaphyr shows it to be discordant with the
structure of the sediments under any interpretation of the latter that
has been offered. The second conclusion follows directly upon the
first.”

While these problems occupy most of the paper, space is given to a
new interpretation of the structure of the Chestnut Hill slates and the
northern conglomerate, which harmonizes with the field evidence better
than any of the earlier views. Tee

320 The American Geologist. May, 1901.

MONTHLY AUTHOR’S CATALOGUE

OF AMERICAN GEOLOGICAL LITERATURE
ARRANGED ALPHABETICALLY,

Adams, Frank D.

George M. Dawson. (Science, vol. 13, pp. 561-563. Apr. 12, 1901,
Portrait.)

Ami, H. M.

On a new or hitherto unrecognized geological formation in the
Devonian system of Canada. (Can. Rec. Sci., vol. 8, pp. 296-306, 1901.)
Ami, H. M.

On the geology of the principal cities in Eastern Canada. (Trans.
Roy. Soc. Can., second series, vol. 6, pp. 125-164. 1900.)

Ami, H. M.

Synopsis of the Geology of Canada; being a summary of the prin-
cipal terms employed in Canadian geological nomenclature. (Trans.
Roy. Soc. Can., second series, vol. 6, pp. 187-225. March, rgo1.)
Babcock, E;.J;

Report of the Geological survey of North Dakota. First biennial
report, pp. 103. Grand Forks, 1901.

Bayley, W.S.

The geological features of the Menominee Iron district of Michi-
gan. ([Abstract|)) (Geroc. Ay AALS. 1000) p. 180.)

Bell, W. T.

Concretions of Ottawa county, Kansas. (Am. Jour. Sci., vol. 11,
pp. 315-316, Apr.. 1901.)

Brown, Joseph Stanley.

Index to vols. 1 to 10. (Bull. Geol. Soc., America Index vol., pp.
1-200. )

Buchan, J. S.

Was Mount Royal an active volcano? (Can. Rec. Sci., vol 8, pp.
321-329, IGOI.)

Clarke, J. M.

Eighteenth annual report of the State Geologist (New York) for
the year, 1898. Octavo, pp. 169. 1899.
Clarke, J. M.

Lenticular deposits of the Oriskany formation in New York. [Ab-
stract.|) | i(Proc A. A. 3AMS? Beco putes»)

Clarke, J. M.

The fauna of the arenaceous lower Devonian of. Aroostock county,
Maine. [Abstract.] (Proc. A. A. A. S., 1900, p. 188.)
Cooper, W. F. (A. C. Lane and)

Fossils of the Marshzll and Coldwater. (Rep. Geol. Sur. Mich.,
vol. 7, part 2, pp. 252-204.)

Author's Catalogue. 321

Cushing, H.P.

Preliminary report on the Geology of Franklin county. Part 3.
(18th Ann. Rep. of the State Geologist of New York, pp. 73-128, 1890.)

Daly, Reginald A.

The Physiography of Acadia. (Bull. Mus. Com. Zoology, vol. 38,
pp. 73-104, pls. II, 190I.)

Dawson, Geo. M.

Geological Record of the Rocky Mountain Region in Canada.
(Bull. Geol. Soc. America, vol. 12, pp. 57-02.)

Dresser, John A.

A hornblende lamprophyre dike at Richmond, P. Q. (Can. Rec.
Sci., vol. 8, pp. 315-321, Ig0I.)

Dryer, Chas. R.

Certain peculiar eskers and Esker lakes of Northeastern Indiana.
(Jour. Geol., Feb.-Mar., 1¢o01, pp. 123-130.)

Ellis, R. W.

Ancient channels of the Ottawa river. (Ottawa Nat., vol. 15, pp.
17-30. Apr., I9OT.)
Fairbanks, H.W.

Pyramid Lake, Nevada. (Pop. Sci. Month., vol. 58, p. 505, March,
190I. )

Farrington, O.C.

Observations on Indiana caves. (Field Col. Mus., Geol. Ser., ve:.
I, pp. 247-266. Feb., 1901.)

Farrington, O.C.

The structure of Meteorites. (Jour. Geol., Feb.-Mar., 1901, pp.
174-101.)

Fuller, Myron L.

Notes on an unusual Urientation of Phenocrysts in a Dike. (Tech-
nology Querterly vol. 12, no. 2, June, 1890, pp. 175-179.)

Gidley, J. W.

A new species of Pleistocene horse from the staked plains of Texas.
(Bull. Am. Mus. Nat. Hist., vol. 13, p. 111, Dec., 1900.)

Gould, C.N.

Tertiary springs of western Kansas and Oklahoma. (Am. Jour.
Sci., vol. 11, Apr., 1901, pp. 253-262.)

Hall, C. W.

The Chengwatona series of the Keweenawan. [Abstract.] (Proc.
A. A. A. S., 1900, p. I9I.)

Hallock, Chas.

One of Canada’s Explorers (Robt. Bell), pp. 10. Washington, D.
C. Extracted from Forest and Stream.

Hatcher, J. B.

Some new and little known fossil vertebrates. (Annals of the Car-
negie Museum, Pittsburg, vol. 1, pp. 128-144, pls. I-3, 1901.)
Hershey, Oscar H.

Metamorphic Formations of Northwestern California. (Am. Geol.,
vol. 27, pp. 225-245, April, 1901.)

322 The American Geologist. May, aes

Hilgard, E. W.
A historical outline of the geological and agricultural survey of the
state of Mississippi. (Miss. Hist. Soc., vol. 3, pp. 207-234, 19o0r.)

Hill, B. F. (J. F. Kemp and D. H. Newland)

Preliminary Report on the Geology of Hamilton, Warren and
Washington counties. (18th Ann. Rep. State Geologist of New York,

pp. 141-162, 1899.)
Hobbs, W.H. .

The still rivers of Western Connecticut [Abstract]. (Proc. A. A.
A. S., 1900, p. 190.)

Hobbs, W.H.

The Geologist awheel. (Pop. Sci. Month., vol. 58, p. 515, Ma-ch,
tor. )

Julien, A. A.

The genesis of the pegmatite in North Carolina [abstract]. (Proc.
A. A. A. S., 1900, p. 189.)

Kemp, J. F. (and D. H. Newland and B. F. Hill)

Preliminary Report on the Geology of Hamilton, Warren and
Washington counties. (18th Ann. Rep. State Geologist of New York,
pp. 141-162, 18990.)

Kummel, H. B.

The Newark, or New Red sandstone rocks of Rockland countv, N.
Y. (18th Ann. Rep. State Geologist, pp. 11-50, 1899.)

Lane, A. C. (and W. F. Cooper)

Fossils of the Marshall and Coldwater. (Rep. Geol. Sur. Mich.,
vol. 7, part 2, pp. 252-204.)

Leverett, Frank

Old channels of the Mississippi in Southeastern Iowa. (Annals
of Iowa, April, 1901.)

McGee, W. J.

Occurrence of the Pensauken formation within the limits of the
city of Washington, [abstract]. (Proc. A. A. A. S., 1goo, p. 187.)
Merrill, George P.

Guide to the study of the collections in the section of applied ge-
ology. The non-metallic minerals. (Rep. of the U. S. Nat. Mus. for
1899, pp. 155-483, 30 plates, I9o0T.)

Newland, D.H. (C. H. Smith and)

Report on progress made during 1898 in mapping the crystalline
rocks of the western Adirondacks. (18th Ann. Rep. State Geologist,

pp. 129-135, 1899.)
Newland, D. H. (J. F. Kemp and B. F. Hill)

Preliminary report on the Geology of Hamilton, Warren and
Washington counties. (18th Ann. Rep. State Geologist of New York,

pp. 141-162, 1899.)
Pearson, H.W.

Oscillations of the sea-level (1). (Geol. Mag., vol. 8, pp. 167-174,
Apr., I901.)

Author's Catalogue. 323

Prosser, C.S.

Sections of the Formations along the northern end of the Helder-
berg plateau. (18th Ann Rep. State Geologist of New York, pp. 51-72,

189. )
Salisbury, R. D.

Certain late Pleistocene loams of New Jersey and adjacent states.
lepstract: |» *(Broc, Ay A. A. S.,1900}.p. 192.)
Sardeson, F. W.

Problem of the Monticuliporoidea. (II). (Jour. Geology, Feb.-Mar.,
1901, Pp. 149-179.)
Schuchert, Charles

On the Helderbergian fossils near Montreal, Can. (Am. Geol.,
vol. 27, pp. 245-253, April, 1901.)
Smith, James Perrin

The principles of Paleontologic correlation [abstract]. (Proc. A.
A. A. S., 1900, p. 193.)
Smyth, C. H. Jr. (and D. H. Newland)

Report of Progress made during 1898 in. mapping the crystalline
rocks of the western Adirondack region. (18th Rep. State Geologist,

PP. 129-135, 1899.)
Upham, Warren

Drift erosion, transportation and deposition [abstract]. (Proc. A.
A. A. S., 1900, p. 190.)
Watson, Thomas L.

Weathering of granitic rocks of Georgia. (Bull. Geol. Soc. of
America, vol. 12, pp. 93-108, pls. 6-11.)
Watson, Thomas L.

On the origin of the phenocrysts in the porphyritic granites of
Georgia. (Jour. Geol., Feb.-Mar., 1¢01, p. 97.)
Watson, Thomas L.

The granitic rocks of Georgia and their relationships. (Am. Geol.,
vol. 27, pp. 199-225, pls. 17-24. April, 1901.)
Weller, Stewart

Correlation of the Kinderhook formations of southwestern Mis-
souri. (Jour. Geology, Feb.-Mar., 1901, pp. 130-149.)
White, David

Some paleobotanical aspects of the upper Paleozoic in Nova Scotia.
(Can. Rec. Sci., vol. 8, pp. 271-280, 1901.)

Whitfield, R. P.

Note on the principal type specimen of Mosasaurus maximus, Cope,
with illustrations. (Bull. Am. Mus. Nat. Hist., vol. 13, pp. 19-23, pls.
1 and 2, Dec., 1900.) :

Willis, Bailey
Thomas Benton Brooks. (Science, Mar. 22, 1901.)

324 The American Geologist. May, 1901

CORRESPONDENCE.

ARE THE AMYGDALOIDAL MELAPHYRS OF THE BOSTON
BAsIn INTRUSIVE. OR CONTEMPORANEOUS?—The recent pa-
per by my friend, Henry T. Burr on the “Structural Rela-
tions of the Amygdaloidal Melaphyrs in Brookline, New-
ton and Brighton, Mass.,’’* is, in the main, a criticism of my
view that the melaphyrs of this area, as of the other parts of
the Boston Basin, are chiefly contemporaneous, and of an un-
published map by Woodward in which that view is embodied.
I have not claimed that the melaphyrs are wholly contempo-
raneous, recognizing that they must be intrusive at some
points, since the magma necessarily reached the earth’s sur-
face before it could play the role of an effusive; but in the
area which he has studied, Mr. Burr finds all the melaphyrs
to be intrusive.. His argument rests largely upon the evi-
dence of the contacts, which are found to be, without excep-
tion, where clearly exposed, igneous. Details which appear
to support this thesis are made the most of; but broad, funda-
mental facts which tell strongly against it have not been duly
considered. No attempt is made to show that none of the
irregular contacts supposed to be igneous could be as well
explained as due to the covering by sediments of the cracked
and scoriaceous surface of a submarine flow; or that the sup-
posed baking of these overlying sediments is never silicification
accompanying the chloritization of the melaphyr. The ori-
entation of feldspars in conformity with the contact is em-
phasized, although this feature belongs also to the free sur-
face of a flow, and not alone to its igneous contact with an-
other rock. Notwithstanding the title of his paper, as quot-
ed above, our author takes absolutely no account of the very
prevalent amygdaloidal and scoriaceous textures of the
melaphyr and his sections show dykes of melaphyr
from 500 to more than 3,000 feet in width. He _ starts
out by noting that the melaphyr and the trap dikes of the dis-
trict are, petrographically, hardly distinguishable; but does
not attempt to show why, if the trap and the melaphyr are
both intrusive, a three-thousand-foot dike of the melaphyr
should be throughout amygdaloidal, scoriaceous or aphanitic,
while a three-foot dike of trap is holocrystalline and homoge-
neous. If these masses of melaphyr really are dikes from
500 to 3,000 feet wide, it would be very interesting to know
where and how they terminate; and certainly a fissure 3,000
feet wide filled with basic magma at a level in the crust per-
mitting it to solidify with aphanitic and vesicular textures
could not have failed to gush effusively at the surface; but
no suggestion is offered as to what has become of this effu-

* Bull. Mus. Comp. Zool., Geol. Series, 5, 53-69.

Corresponde::. . : 325

sive material. These supposed dikes are represented as
transverse to the dip of the enclosing strata; but their close
conformity with the strike of the sediments is not explained.

Another fundamental fact which is overlooked is the oc-
currence in this area, and in intimate association with the
melaphyr, of important beds of melaphyr tuff. The genetic
relations of the tuff to the melaphyr cannot be questioned ;
_and the existence of the former should be regarded as conclu-
sive as to the contemporaneous origin of a part at least of
the latter. Much is made of the supposed absence of mela-
phyr pebbles in the overlying conglomerates. These are not,
however, wholly wanting; and at some points they are a very
‘striking and significant feature of the contact. For instance,
between Newton Upper Falls and Newton Highlands, in the
western part of Mr. Burr’s field, a north-south section shows,
if there be no repetition of the strata by strike faulting, four
heavy beds of conglomerate and sandstone, all dipping in a
general northerly direction at angles of twenty to forty de-
grees, separated by three broad bands of melaphyr. The most
clearly exposed contact in this series is the uppermost, or that
between the northern band of melaphyr and the overlying con-
glomerate. This melaphyr is, in the southern (lower) part of
the band, a solid and homogeneous rock of approximately holo-
crystalline aspect ; but northward it becomes more slaty, in part
amygdaloidal, brecciated and scoriaceous ; and at last is decid-
edly shaly in structure, looking more like a tuff than a flow.
It is covered by the conglomerate with apparent conformity ;
and the conglomerate is, on and near the contact, not injected
by the melaphyr, but crowded with angular fragments of pre-
cisely similar melaphyr. Within a yard above the contact the
melaphyr detritus begins to die out: and at a distance of two
yards an occasional fragment only is to be found. The mela-
phyr in the conglomerate is clearly a contact feature; and it
can not be doubted that this body of melaphyr was in existence
as a surface formation when the deposition of the conglomer-
ate began. Everything goes to indicate that these effusive
eruptions were submarine; and at Nantasket, as also in Brigh-
ton, we have conclusive proof, in the well preserved wavy and
ropy surfaces of the flows, that in some instances they were
covered without suffering erosion.

The main bodies of melaphyr, throughout the Poston basin,
have all the characters of lava flows and are essentially unlike
any known dikes or sills. In other words they are masses
which fundamental and indisputable facts indicate to be con-
temporaneous. And yet, because of certain minor ifregular-
ities of contact and appearance of baking, etc., they are de-
scribed as intrusive ; and highly improbable sections, with trans-
verse dikes thousands of feet wide, are constructed to explain

their structural relations. Apparently,.every irregular or
transverse contact is to be regarded as igneous, ignoring all
the raggedness of a normal lava flow, to say nothing of subse-
quent faulting and crushing, and ignoring the almost inevitable
induration by silicification, of a sediment in contact with such
a prolific source of free silica as these basic lavas were dur-
ing the process of chloritization ; and certainly nothing is more
normal than the impregnation of sediments in contact with a
basic eruptive by ferruginous minerals, thus readily explaining
directly or by subsequent oxidation the very local reddening of
the sediments, extending commonly less than an inch from the
contact, to which Mr. Burr attaches much importance. Of the
excess of free silica during the alteration of the melaphyr we
have substantial evidence in the quartz and jasper amygdules
and segregations which often crowd the melaphyr and the nu-
merous veinlets of quartz frequently to be observed in the im-
mediately bordering sediments.

Mr. Burr then discusses the structure of the region, to show
that the melaphyrs are not confined to a particular horizon or
limited part of the sedimentary series and that they are not
continuous at any horizon. These contentions must be conced-
ed, and so far as I know have never been questioned ; but they
are certainly, to say the least, very inconclusive as arguments
against the contemporaneous origin of the melaphyrs ; for there
is no apparent reason why the volcanic activity should have
been sharply localized in time, and certainly aerial continuity is
no more essential to effusives than to intrusives.

The account of the structure of this area on pages 61 to 66
fails to indicate that the main features had been previously de-
scribed. Reference may be made especially to the detailed ac-
count of the thrust fault between the slate and the northern
conglomerate. This is fully described and figured in my Con-
tributions to the Geology of Eastern Massachusetts, published
in 1880. I described it again, and with additional emphasis
upon its structural importance in 1884 (Proc. Bost. Soc. Nat.
Hist., 23, 24-27) ; and still again in 1889, in my lectures on the
Physical History of the Boston Basin.

So much it has seemed necessary to write in the interest of
truth; but it is only fair to add that the impetuous following
of a narrow line of argument to its logical conclusion, regard-
less of obvious and important counter arguments, which Mr.
- Burr’s paper illustrates, is the more surprising since the author
has previously done most excellent geological work; and the
explanation is undoubtedly to be found in a hasty study, under
unfavorable conditions by a mind of more than ordinary ener-
gy, directness and influence. As an example of Mr. Burr’s
better work, and as an indication of what may be hoped from
him in the future, [ may mention his brilliant paper of a year

Personal and Scientific .News. 327°

ago on a new Lower Cambrian fauna from Eastern Massachu-

setts, which I have elsewhere described as unquestionably the

most important contribution to the paleontology of the Boston

Basin since the discovery of Paradoxides by professor W. B

Rogers, nearly fifty yearsago. W. O. Crossy.
Institute of Technology, Boston, April, rgor.

PERSONAL AND SCIENTIFIC NEWS.

Dr. . E. Grecory has been promoted professor of physi-
cal geography at Yale University.

Pror. G. H. Barton, of the Massachusetts Institute of
Technology, plans to spend the summer in Europe.

Pror. S. CAtvin, of lowa Crry, recently visited Montana
for the purpose of making a special examination of the Great
Falls coal basin.

Dr. T. Nevson DALE has resigned as instructor in geol-
ogy and botany at Williams College, and will leave Williams-
town during the summer.

Mr. W. S. GReESLEY, of Eria, Pa., sailed for England on
April 17th, where he is to take up professional work in con-
nection with mining and geology.

THE OFFICE OF THE STATE GEOLOGICAL SuRVEY OF MiIs-
sourI has been moved from Jefferson City, the capital, to
Rolla, where the State Mining School is situated.

RicHARD P. ROTHWELL, founder and editor of the En-
gineering and Mining Journal, and editor of the yearly volumes
of The Mineral Industry, died at his home in New York City
on April 18th.

At a Recent MEETING OF THE Boarp or Trustees of the
Ohio State University John A. Bownocker was promoted to be
professor of inorganic geology and Charles S. Prosser to be
professor of geology and head of the department.

Ir 1s SAID THAT FOR THE FEw Open Positions on the Ge-
ological Survey of Canada, a hundred applications have been
received. This competition is due in part to the interest in ge-
ology awakened by recent developments of an economic nature
in the Dominion.

Mr. THomas W. ALLEN, St. Joseph, Mo., reports the dis-
covery of a very fossiliferous stratum of gray sandstone about
60 feet above the bed of the Missouri river at that place,
12 to 14 inches thick. The rock is a mass of fossil plants con-
sisting of ferns, calamites, Lepidodendrons, Sigillaria, broad-
leaved plants, nuts, fruits, seeds etc. many varieties.

GEOLOGICAL SociETY OF WaASHINGTON.—The program for
the meeting of April 3d, was as follows: “The priceite of Lone

328 The American Geologist. May, 1901.

ranch, Curry Co., Oregon,” J. S. Diller; “The problem of
Archean,’ C. R. Van Hise. At the meeting of April roth the
following was the program: “The Philadelphia gneisses,” Miss
F. Bascom; “Possible Pre-Wisconsin tills of Massachusetts,”
M. L. Fuller; “The Waverly group of Ohio,” G. H. Girty.

NaTIONAL MusEuM For Canapa.—lIn the supplementary
estimates to be laid before parliament in the course of a few
days there will be included a substantial sum of money to be
devoted toward the erection of a national museum of geology
and natural history for the magnificent collection now accom-
modated in the Geological Survey building, Sussex street.
The edifice will be of ‘sufficient size and in design worthy of the
purpose to which it is to be put.

Dr. R. A. F. PENROSE of the Journal of Geology editorial
staff, is about to undertake a journey around the world for
the purpose of visiting the mines and mineral deposits of
greatest interest. It is his intention to begin with the older
Cornish tin mines and the chief mineral localities of England.
Thence he intends to pass to Sweden and after visiting her
principal objects of interest, to proceed by steamer from Stock-
-holm to St. Petersburg. When he has completed his tour of
observation of the mines and minerals of Russia he will go via
the trans-Siberian railway to the Pacific and back to the dia-
mond and gold fields of South Africa. Ceylon and Burmah
will be visited, if possible, and he will return to California in a
year or more.

J. Prerpont Moreav, the financier of New York City, one
of the trustees of the American Museum of Natural History,
was the donor of the Bement collection to that institution.
This is probably the finest donation. of minerals ever made to
any institution. It is valued at from $150,000 to $200,000, and
was called after Clarence S. Bement, of Philadelphia, who be-
gan the collection 35 years ago, and kept adding to it until it
passed from his possession. Neither time nor money was
spared in gathering desirable specimens, and in 1884 the Be-
ment collection was looked upon as so important as to call for a
special report in the interest of the National Museum, Wash-
ington. It was expected at one time that this collection would
become the property of the government. A curator of a for-
eign museum, after seeing the Bement collection went to Eu-
rope. He cabled that he. would purchase the specimens, but
did not succeed in raising the necessary money. Since 1884
the Bement collection has increased over 50 per cent.

These accessions to the collection raise the American Mus-
eum of Natural History to rank among the museums of the
world like that of the British Museum, heretofore, by common
consent, considered as rich beyond comparison in rare speci-
mens.

Personal and Scientific News. 329

NEUTACONKANUT’S GREAT BOULDER.—This was described
by Dr. C. T. Jackson in his report on the Geological and Agri-
cultural survey of Rhode Island in 1840. It is in Johnson, near
Providence. It is shown in a halftone cut in the Providence
Journal of March 24. The boulder still rests where it did in
1840 and for centuries previous. The traveler in passing
still takes a second look to see if itis really about to topple over
and rol! down the hill into the highway. It is a striking fea-
ture of the landscape, and will ever remain as an object lesson
to the geologist, and a topic of interest to the casual observer.

Following is Dr. Jackson’s description: ‘The rocks on
Neutaconkanut Hill are alternate strata of micaceous and
hornblende slate, the former being very much contorted. On
the south side of the hill there may be seen a huge boulder of
hornblende rock poised upon the mica slate. This rock must
have originated elsewhere, and it now rests in an accidental po-
sition, as will be evident to anyone who examines the situation
in which it is placed. Since hornblende rocks do occur at the
northward, and not to the southward of the place where this
block is now found, we feel confident that this immense rock has
been removed southwardly from its parent ledge and deposited
on the rocky strata where we now find it.”

Fretp Work Metnops tn GEOLOGY AT HArvArD.—The el-
ementary laboratory and field course at Harvard this year has
enrolled about 190 men. The class is divided into three sec-
tions and each section into three companies for field work.
The following memorandum has been issued to each student
as a reminder of what he may exnect to find in the field ex-
cursions. The assistants in charge of each company follow up
this outline with questions and remarks called out by the par-
ticular locality. The students’ results are handed in at the close
in the form of a brief report with maps and sections.

Geology 5. Field Season of 1901. Brief Synopsis of Queries An-
swerable by Personal Observation—Ask yourself on arriving at a
locality selected for study whether it is an area of erosion or deposi-
tion. If an area of erosion,—what agent or agents are now at work
or have been at work in the immediate past? Waves, currents, rivers;
winds; ice or glaciers; life; weathering, disintegration, decomposition ?
What land forms have resulted from erosion? What new deposits
have been made?

If an area of decomposition.—what materials are accumulating ”
What is their form? What is their structure?

In the case of a rock in situ—what kind of rock is it? Jf—(a) an
igneous rock,—What is its form? Batholith, laccolith, dike; sill, lava-
flow, volcanic neck? What is the country rock? Where are the con-
tacts? Is it intrusive? What is the mineralogical composition of the
rcck? What is the structure of the rock? Crystalline, porphyritic,

330 The American Geologist. May, 2a.

glassy or devitrified? Has it flow structure? Is it vesicular, amygda-
loidal, spherulitic ?

(b) A veinstone-—What mineral or minerals com:pose it? What has
been the order of their growth or genesis? What is the country rock?
Did it furnish the substances in the vein? What is the nature of the
cavity in which the vein is deposited? What rock movements are
shown? Is there any volcanic breccia? When did the vein form in
relation to other structures or rocks?

(c) A clastic rock—What is it? A conglomerate? If so, what
rocks form the pebbles? What is the cement? How was the conglom-
erate formed? If a sandstone, what is it composed of? What is the
cement? Ifa pelite, what is its structure, lamination, banding, or strat-
ification? Are there fossils?

(d) A metamorphic rock—What is its structure, composition ?
What was it originally? What has produced the metamorphism ?

In any case, what is the attitude of the rock? strike, dip? Has it
been jointed, folded, faulted, tilted, metamorphosed? Has it slaty
cleavage? dip and strike of same? What is the age of the rock relative
to others of different kind? In what order do the secondary structures
intersect ?

What has been the succession of events in the area studied?

THE SPENDIAROFF PRIzE.—The following letter may per-
haps explain itself: Le Congres géologique international, dans
sa séance générale du 25 Aout 1900, a nommé membres de la
Commission du prix international Spendiaroff: MM. Albert
Gaudry, président; Marcel Bertrand, Sir Archibald Geikie,
Karpinsky, Tscherneyschew, Zirkel et Von Zittel. Cette Com-
mission propose comme sujet de prix pour 1903 :

Revue critique es methodes de classification des roches.

Dans la séance du 20 Aotit 1900, le Conseil du Congrés
avait décidé que les ouvrages présentés pour le concours seront
envoyés au Secrétaire général du dernier Congrés au nombre
deux exemplaires au moins, et que l’envoi sera fait au plus tard
une année avant la session suivante. Le Conseil a décidé aussi
que le droit de priorité pour obtenir le prix appartiendra aux
ceuvres traitant les sujets proposés par le Congres.

Les envois doivent étre addressés a4 M. Charles Barrois,
Secrétaire Général du Congrés géologique international, 62
boulevard Saint-Michel, Paris.

La valeur du prix est de 456 roubles, c’est-a-dire environ
1.200 francs, d’aprés l’indication de M. Karpinsky.

En vous communiquant ces renseignements, nous avons
lVhonneur de vous prier d’en faire part aux savants qu ils pour-
raient interesser.

Veuillez, Monsieur, agréer l’expression de nos sentiments
les plus distingués.

Abert Gaupry, Le Président du Congres.

CHartes Barrots, Le Secrétaire général.

”

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THE AMERICAN GEOLOGIST, VOL. XXVII. PLATE XXVI.

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- THE

Mee RICAN GEOLOGIST.

Voit. XXVII. JUNE, 1go1. No. 6.

THE ONTARIO COAST BETWEEN FAIRHAVEN
AND SODUS BAYS, NEW YORK.
By J. O. MarTIN, Cornell University, Ithaca, N. Y.

PLATES XXVI and XXVII.

During the summer of 1900, whiie engaged in a study of the
New York state drumlin area, | became interested in the pecu-
liar shore phenomena of that part of the Ontario coast lying
between Fairhaven and Sodus bays. The drumlins which so
thickly beset the south-lying plain are here brought to an ab-
rupt termination by the erosive action of the lake. The re-
sulting coast line, being of an unusual type, has seemed to me
worthy of a brief description.

Viewed from a boat passing along shore, this coast presents
a series of semi-elliptical bluffs which are wave-cut drumlin sec-
tions and these bluffs are connected, one to another, by low-ly-
ing beaches. A closer inspection of these drumlin cuts shows
them to be composed of the usual stiff boulder clay, which, in
this case, contains a very large percentage bf Medina sand-
stone. The intervening beaches are composed of the coarser
gravel and boulders of this drumlin till with little or no sand.
Between the drumlins and behind their connecting beaches,
lies a series of more or less extensive ponds and swamps. The
above features are well shown on the accompanying map,
(pl. XXVI), which is a part of the “Oswego Sheet” of the
United States Geological Survey map and may be taken as typ-
ical of the whole stretch of coast under consideration.

At the close of the Glacial period when lake Ontario had
assumed its present level, the drumlins extended out into the
. lake, forming a quite continuous series of islands. The gener-
al northeast and southwest trend of this coast exposed it to the

332 The American Geologist. June, 1901.

most violent and frequent winds of our northern climate; con-
sequently and because of the absence of bed-rock its develop-
ment has been quite rapid. When wave erosion first began to
cut into the drumlins, sea cliffs were formed on all sides of
the drumlin islands and traces of these cliffs still exist, in some
cases with large trees growing thereon.

As a result of their more exposed position, however, the
northern ends were cut back most rapidly and then began the
growth of the connecting beaches. The waves loosened from
the drumlins more material than they could grind up and this
material began to travel along shore, moved by the diagonally
approaching waves, now in one direction, now in the other, but
always gaining in the direction away from the most frequent
winds. Slowly beach-bars grew out from each end of the sea-
cliffs on the northern end of the drumlins, and these joined
with those of the neighboring drumlins, tying them together
and producing a continuous coast line.

On the drumlins where wave erosion is most rapid, nearly
vertical cliffs are formed and the stiff drumlin till exposed to
the combined action of weathering and erosion assumes the
most fantastic forms. Buttress-like projections stand out from
the cliff face, their upper edges reduced by rain erosion to
sharp, thin, knife-like edges. Between these buttresses are
ditch-like depressions down which streams of mud flow during
wet weather. On such of the drumlins as are tree-covered
there is a continual down-sliding of undermined trees and the
farmers of this region, well knowing how rapidly their land
is disappearing, place only temporary fences along the cliff
edges. The very steepness of the cliffs of boulder clay shows
how rapid this wearing back must be.

As the drumlin cliffs are cut back by wave erosion, the
beaches are constantly changing their form and moving shore-
ward. From the data obtained from the farmers who note the
necessary moving of fences and the shrinking of their fields, I
have estimated that the cuts are moving backward from a few
inches to ten feet a year where cutting is most rapid. Since
the retreat of both the sea cliffs and beaches depends upon the
rapidity with which the waves grind up and carry away the
-material loosened from the drumlins it is interesting to note
the following fact which indicates, in a way, how rapid this
process is.

ee ee ae

— en

LIBRARY

OF THE

UNIVERSITY of ILLINOIS.

‘

THE AMERICAN GEOLOGIST, VOL. X XVII. PLATE X XVII.

1. Drumlin Cut showing Down-sliding of trees. 2. View along an Inter-diumlin Beach.
3. Inter-drumlin beach and enclosed pond. 4. Beach bar nearly enclosing ‘*The Pond.”
5. Steep Faced, Drumlin Cut. 6. Old Beach at Base of Old Sea Cliff.

THE ONTARIO Coast BETWEEN FAIRHAVEN AND Sopus Bays, NEw YorK.

Ontario Coast, Fairhaven and Sodus Bays.—Martin. 333

My first visit to this coast was in the spring. At this time,
owing to thawing and to the great quantities of water in the
drumlin till large masses of clay were constantly sliding down
to the waves. As a consequence of this rapid supply the
beaches in front of the cuts had large numbers of the charac-
teristic angular and striated pebbles so abundant in drumlin
till. A visit three weeks later to the same point showed very
few angular pebbles and these few had evidently just fallen
down. In the short period of three weeks, then, the hard
Medina sandstone pebbles had been so worn down as to have
lost all traces of their angularity.

The ponds and lagoons in the rear of the beaches receive
the whole of the land drainage and consequently the sediment
which the streams are bringing down. The sediment is depos-
ited in the ponds while the water flows into the lake, either by
filtering through the porous gravel beaches, or, as in the case
of “The Pond” (see'map), by keeping for itself an open pas-
sage through the beach. Sediment and abundant aquatic veg-
etation are rapidly filling these ponds and in some cases have
completed their task.

By a reconstruction of the truncate drumlins (see map),
one can see that there has been a retreat of the off-shore
beaches and drumlins of from a fourth to half a mile. As to
how much farther north these drumlins extended we have no
certain data; but the presence of several boulder pavements at
a considerable distance off shore, having the basal outline of
drumlins, seems to indicate. the former. positions of drumlins
which have been completely cut away. These boulder pave-
ments are of very large boulders, such as the waves would have
been unable to remove. Just such boulders are now to be seen
off the northern ends of the existing truncated drumlins.

We have‘in the formation of the above described inter-
drumlin beaches a striking illustration of the power of waves
as a transporting agent and proof of their importance in shore
phenomena. Professor Tarr, in a paper on “Wave Formed
Cuspate Forelands,’”* call attention to the importance of wave
transportation as a cause for many cuspate forelands; and
since waves seem to me the most important along-shore agents,
I have made some observations which show in a definite man-

* American Geologist, vol. xxii, 1898, p. 1.

334 The American Geologist. June, 1901.

ner how rapidly the material of these beaches is moving. In
order to test the rapidity of this movement, I selected from the
beach two pebbles which were striking enough to be easily dis-
tinguished from the others. One of these pebbles was spher-
ical in form, the other had a roughly triangular outline with
two flattened faces. The first of these, (weighing half an
ounce), was thrown into the zone of wave action at a time
when the waves were breaking at an average hight of six
inches and at an angle of fifty degrees with the shore. It im-
mediately began to move in a zigzag course along the beach,
now washed diagonally upward upon the beach, now rolling
backward with the returning wave. The two motions thus de-
scribed were at an angle with each other and the apex of this
angle pointed. shoreward. Frequently the along-shore shove
resulting from these two motions was as much as two feet,
though its general average was sixteen inches. At one time
this pebble moved three yards in nine minutes, at other times,
however, the specimen became buried by the rolling mass of
pebbles and it would be some time before the waves would un-
cover it and start it along again. The larger of the two speci-
mens weighed seven ounces and this when the waves were
breaking at a hight of twelve inches, gave as a result of three
trials, a linear motion of sixteen yards in ten minutes. With
stronger winds, observations were impossible for the waves
then became so muddy that one could not follow the move-
ments of the specimen.

At. the entrance to: “The Pond”. (sée-map), there sam
curious hook on the end of the eastern beach, which is kept
from growing across this entrance by the outflow of the land
drainage and also by the piling up of the water in “The Pond”
during stormy weather. During a strong on-shore wind the
water backs up into this bay until the level of the water in
“The Pond” is higher than that of the lake. When the wind
subsides the water runs toward the lake again with a consid-
erable current. This current, however, is not able to carry
back the materials washed in by the more powerful waves.
Here again the waves are the most important factor and the
current, though stronger than most currents in the lake, is ca-
pable of moving little else than sand and clay.

International Congress of Geologists —Frazer. 335

EIGHTH SESSION OF THE INTERNATIONAL CON-
GRESS OF GEOLOGISTS, PARIS, 1900.

ITS PROCES VERBAUX WITH RUNNING COMMENTS.

PERSIBOR FRAZER, Philadelphia. Pa.

A volume, royal 8vo of 62 pp. has been issued by the
French ministry of commerce, trade, post and telegraph giy-
ing the procés verbaux of the eighth session, held at Paris last
year from the rOth to the 27th of August. The promptness
with which all the publications of the last Congress have been
issued, is an unmistakable indication of the directing power of
Charles Barrois, the able general secretary.

After an enumeration of the twenty-five excursions, fol-
low the more or less formal addresses of the retiring president,
Karpinski (who was reé-called to Russia a few days after-
wards by a death) and of the incoming president, Gaudry.
The announcement by the latter of the deaths of the former
members of the Council, Lieut. General de Tillo, Hauchecorne,
Janettaz, James Hall and Marsh seems to have been errone-
ously printed “since 1878” (the date of the first meeting of the
Congress in Paris). In point of fact all these eminent men
appear to have died since the St. Petersburg session of 1897.
In’ Barrois’ report the happy solution of a difficulty which
threatened the success of these International Congresses is an-
nounced. It was to organize two sets of excursions, the first
open to practically any one who cared to take part, but the
second restricted to professional and practising geologists. For
several sessions the local committees have staggered under the
increasing burden of providing for the transportation and
maintenance at a minimum price of great numbers of persons,
chiefly foreigners to the country where the session was held,
who read in the newspapers of the excursions planned for the
geologists, and determined to profit by them as personally con-
ducted tours to which the payment of an entrance fee of twen-
ty-five francs, entitled the payer. This imposition was most
severely felt at the St. Petersburg session in 1897.

Six months before the opening of the session, the news-
papers throughout the world had announced the generous plans
of the Russian local committee to carry two or three hundred
members’ of the Congress in special trains, steamers, and

330 The American Geologist. Janes oe

coaches over the Urals and Caucasus. The benefits to be en-
joyed by such excursions appealed to many persons who knew
little of Russia and nothing of geology, but who could easily
spare five dollars to become a “member” of the Congress, and
the necessary traveling expenses to bring them within the
vortex of Russian hospitality. One gentleman of general but
not geological attainments expressed to the writer his ability
to “hand a grand duchess into the supper room as well as the
best geologist.’ In consequence of the extreme good nature
of the Russians, and the selfishness of the non-geological tray-
elers who desired to take “everything in” the great Ural expe-
dition occupying about a month and employing about thirty
sleeping and dining cars carried 253 passengers of which it
was said fully one-third were not geologists, nor capable of
profiting geologically by what they saw; but kept fully seventy
or eighty deserving geologists from taking part.

Unfortunately the United States had a larger misrepre-
sentation, both male and female, in this fraudulent practice
of ride stealing than any other country. The debates upon the
subject were warm, but without result. The method-of M.
Barrois, which might be compared to a lightning arrester,
solves the the difficulty with least friction.

The following reports of committees were presented:

rt. On geological nomenclature by M. Tschernyschew.

2. On the map of Europe by G. Capellini on behalf of the
directors.

3. On petrography by M. Zirkel.

4. On glaciers by M. Richter.

5. Proposition of Sir Archibald Geikie on international co-
Operation in geological investigations.

6. Proposition of M. Oehlert on the reproduction of types.

The jury on the Spendiaroff prize was as follows. Gaudry
(President), Marcel Bertrand, Sir Archibald Geikie, Kar-
pinsky, Tschernyschew, Zirkel and v. Zittel.

The committee on Spendiaroff award was also happy in
preventing the generosity of M. Spendiaroff from becoming a
bad precedent in the administration of the Congress.

The history of this foundation is peculiar.

During the month of excursions prior to the St. Petersburg
Congress, a young man was noticed by all participants, and

International Congress of Geologists —Frazer. 337

especially by the foreigners, for his grace and courtesy in as-
sisting them, and his intelligence and zeal in the science of
geology. During the beautiful Volga steamboat excursions
he will ever be remembered by those who were present for his
delightful singing of the Russian folk songs, both alone and
in chorus. One day in St. Petersburg at the morning session
of the Congress, after the Ural and other ante-session excur-
sions had finally come to a close, the members were shocked to
learn of the sudden death of young Spendiaroff. A few days
aiterwards the president, M. Karpinsky, announced the dona-
tion of his father to found a prize in memory of his son. The
object was most laudable, but many of the members, including
Heckel, feared lest the precedent should be abused by persons
desirous of securing international notice.

The committee appointed to determine the method of apply-
ing this fund has placed it in the Russian treasury to the credit
of the Russian Geological Survey, and the minister of agricul-
ture and domains has offered the interest of the 4,000 Rubles
to the International Geological Congress for a prize to be of-
fered under such conditions as the congress may choose.

This relieves the difficulty of any direct dealings between
the congress and individuals, and avoids the necessity for such
an organization of the former as would enable it to hold and
administer funds. On the whole, in its present shape the
donation may prove beneficial.

It is amusing to note that Karpinsky, without whom the
Spendiaroff prize would never have been attached to the Inter-
national Congress of Geologists, was the first to receive it
nolens volens, although two sessions of the council were occu-
pied with his efforts to avoid this honor.

Vienna was named as the place of the meeting in 1903.

On Archibald Geikie’s motion, a committee (Geikie chair-
man, Horne, Dawson, Tschernyschew, Sederholm, Ramsay,
Chamberlin, Brogger, Reusch, de Geer, Hdgrom, Barrois,)
was appointed to secure more uniformity in the relative studies
of the coast lines of the northern hemisphere—and another
(Credner and v. Zittel, Mojsisovics, von Mojsvar, Tietze,
Geikie, Teall, Renard, Walcott, Chamberlin, Barrois, de Lap-
perent, Capellini, Karpinsky, Alexis, Pavlow, Brogger, Renev-
ier,) to ascertain in what direction international cooperation
in geological investigations is most required.

338 The American Geologist. Juse Lae

Karpinsky and Stefanescu report for Russia and Rou-
mania respectively that these countries have accepted the sug-
gestion of the previous congress in reference to instruction in
geology in the public schools.

M. Karpinsky reports as to the creation of a floating insti-
tute which has presented such great difficulties. It was refer-
red to the Geikie committee on international cooperation.

M. Oehlert’s committee to procure photographic represen-
tations of types of fossil species consists of Bather, Wood-
ward, Frech, von Zittel chairman, Mojsisovics, v. Mojsvar,
Uhlig, v. d. Broeck, Fraipont, Walcott, Williams, Alcmera,
Gaudry, Oehlert secretary, Canavari, Kjoer, Stefanescu, Pav-
low, and Tschernyschew, Choffat, Lindstrom, Lorriol. It was
pointed out that the commission should hasten its work in order
to show a commencement in 1903 at Vienna.

The council legalized by vote the practice which has hither-
to always obtained of relegating to the management of each
council the execution of the work of a congress until the next
session of the congress.

The Meetings of the Sections.
I. General Geology and Tectonic.

Archibald Geikie the president of the section delivered his
address on international cooperation, etc. (Note—It were
greatly to be desired that James Geikie, the president’s talented
and learned brother, took a more active part in these con-
eresses. Especially would his assistance be of value in the
section presided over by his ex-offcial brother.

The papers were:

M. J. Joly, 1) Geological age of the earth determined by the con-
tent of sodium in the ocean;. 2) Experiments concerning denuda-
tion by fresh and by salt water. 3) Order of formation of silicates in
igneous rocks 4) Internal mechanism of marine sedimentation.

M. de Lapparent. On the limit of geological stages.

M. Stanislas Meunier. Subterranean denudation.

M. Bleicher. The denudation of the Vosges.

M. Richter. Report on the works of the Glacial Commission.

H. F. Reid. On the movement of glaciers.

M. Arctowski. The former extension of glaciers in the regions dis-
covered by the Belgian antarctic expedition. \

M. Popovici-Hatzeg. The new geological map of Roumania.

M. Vorwerg. Proposition tending to simplify the notation of dip
and strike of beds.

International Congress of Geologists.—Frazer. 339

The abbe Parat. The grottoes of La Cure.
II. Section of Stratigraphy and Paleontology.

V. Zittel presiding in place of Renevier detained by illness.

The suggestions of the committee have only moderate in-
_terest,or novelty.

One is to substitute “Eo” for “Paleo,” but it has not oc-
curred to the proposer of the change‘ what would be the fate of
“Eozoic” and “Paleo-zoic,’ both terms of great value. As to
eras, Gaudry prefers the terms primary, secondary, and terti-
ary.

Prof. Scott presents to the section the fauna of Patagonia, through
the studies of J. B. Hatcher. The series of beds is thus arranged:

Gault; containing Ammonites resembling entirely the synchronous
fauna of the South of Africa.

Magellian; a terrane of Eocene or Oligocene age.

Patagonian; very fossiliferous Miocene of which the fossils are
closely allied to those of Australia and New Zealand.

Santa Cruz; beds fossiliferous fresh-water Miocene with mammifers
of which the fauna is more closely related to the southern Australian
fauna of Africa than to the northern of America.

Beds of Cape Fairweather; Pliocene age.

M. Bertrand by “gelosic and humic coals,’ comprehends the bog-
head coals and bituminous schists. His paper is original and interest-
ing.
M. Grand Eury. On the rooted stems of the Carbonic terranes.

M. Lemeire. Methodical connection explanatory of the chemical!
formation of various fossil combustibles.

M. H. F..Osborn. 1) “Progress of methods in Paleontology.” 2)
“Correlation between the mammiferous faunz and the Tertiary hori-
zons of Europe and America.” |

The conclusion of this last study is that in these two regions of the
northern hemisphere the paleontology and stratigraphy accord; that the
progress of evolution is parallel if not identical; and that the same di-
visions into stages may be permitted. :

M. Ficheur presented the third edition of the geological map of Al
geria on a scale of 1: 800,000.

M. Flamand. “Geology of South Algeria, high plateaux and moun-
tains of Ksour, and the regions of Sahara.”

M. Donville. 1) “The Jurassic terrane of Madagascar.” 2) “The
geological results of the exploration of M. Morgan in Persia.”

M. Zeiller. “The fossil plants of Tonkin.”

M. Malaise. “The Cambric and Siluric in Belgium.”

M. Oehlert, proposed the foundation of an international publication
for the purpose of re-editing the types of described species anterior to
a certain determined epoch. This proposition was referred to the Coun-
cil.

340 The American Geologist. June; 290s

M. F. Hume. 1) “The rift valleys of Sinai.” 2) ‘Notes on the
geology of the eastern desert of Egypt.” 3) ‘‘The valleys of eastern
Sinai.”

Ill. Section of Mineralogy and Petrography.

M. Michel-Lévy, as president of the international commit-
tee on petrography, read the following suggestions which the
foreign scientific members expressed. 3

First suggestion. The names of the authors shall always be
placed after the names of the rocks as is the custom in zoology
and botany.

Second suggestion. That the congress name an interna-
tional committee to publish the new names of rocks with as
precise a description as possible, with their chemical analyses,
and, if necessary, with an illustration reproducing their struc-
ture. This publication will take place in the transactions of
the congress.

The committee appointed consists of: Rosenbusch, Weit-
schenk, Zirkel,, Boecke, Dolter, Tschermak, A. Geikie, Judd,
Teall,. Twelvetrees, Renard, Hussak, Adams, Ussing, Cal-
deron, Hague, Iddings, Pirsson, Fouqué, Lacroix, Michel
Lévy, Barrois, Ramsay, Sederholm, Sabatini, Struver, Viola,
Koto, Brégger, Reusch, Wichmann, Mrazec, Karpinsky, La-
gorio, Loewinson-Lessing, Zujovic, Duparc, Schmidt, Back-

strom, TorneboOhm. This committee has the right to add to.

its number.

Third suggestion. It is desirable to regulate the nomen-
clature of the eruptive rocks, where the lack of unity is partic-
ularly felt. Different authors attribute different significations
and senses to one and the same name, and conversely different
denominations are employed to designate the same rock, the
same group of rocks, or the same structure. All these incon-
veniences of nomenclature can and ought to be abolished. At
least for the great groups.

Fourth suggestion. The characteristic of the great group
(for example, families) should be based upon the mineralogical
composition, supported by chemical composition and structure.

This request was adopted with 19 dissenting votes. LOow-
inson-Lessing’s motion that chemical composition shall be the
characteristic of first importance in the great groups, received
_ nine votes.

Fifth suggestion. The great groups can be determined at

International Congress of Geologists —Frazer. 341

once, without interfering with the ultimate development of the
classification and dismemberment of these groups in subdivi-
sions. Adopted.

Seventh suggestion. It is desirable to designate the prin-
cipal types of structure by special names. Adopted.

Ninth suggestion. It is necessary to avoid the employment
of the same denomination (of identical term) in different
senses. Adopted.

Tenth suggestion. The employment and creation of dift-
ferent terms to designate the same idea, the same rock, or the
same group of rocks, should be avoided wherever possible.
Adopted.

Thirteenth suggestion. The employment of pre-existing
names, or the assignment to them of a new meaning, by re-
stricting or enlarging their significations, should be avoided
wherever possible.

The secretary exhibited the proof of the petrographic lexi-
con of M. Loewinson-Lessing.

M. Zirkel was elected president of the commission of Petrog-
raphy. An executive committee of the petrographic commit-
tee was chosen, consisting of Becke, Barrois, Brogger, Loewin-
son-Lessing, Pirsson.

IV. Section of Applied Geology.

M. Mourlon. “The new paths of Belgian geology.”
M. Gosselet. “The salt waters met in the aquiferous areas in northi-

ern France.
M. Van der Veur. “The enlargement of the Kingdom of the Neth-

erlands by the drawing of the Zyderzée.”
M. Thevenni. ‘The plateaux of the Hautes Pyrénées and the dunes

of Gascony.”
v. d. Broeck. “The applications of geology.”
M. Kunz. “The progress of the production of precious stones in

the United States.”
M. L. Janet. “The enclosing and protection of the springs of pota-

ble water.”
M. de Richard (read by the president). “The origin of petroleum.” .

Final General Session.

M. Matthew, Jr., presented in the name of his father a
note, printed by the congress, on “The most ancient paleozoic
faune.”

342 The American Geologist. Jue eee

An interesting episode was the reading by the secretary-
general, M. Barrois, of a passage from a note by M. Walcott,
director of the U. S. Geol. Survey, on “Fossiliferous pre-Cam-
bric formation,” in which, relying on the testimony of M.
Rauff, he doubts the existence of the organisms described by
M. Cayeux in the pre-Cambric of Brittany. After the reading,
M. Rothpletz stated that with M. Renard he had seen the sec-
tions described by M. Cayeux and considered the existence of
the Radiolaria in these preparations indubitable.

-M. Pavlow. 1.) “The Portlandian of Russia compared to that of the
Boulonnaise.” 2) “Some methods which might contribute to the elab-
eration of a genetic classification of fossils.”

M. V. de Broeck. “On the Bernissartian.”

M. A. Guebhard. “Tectonic phenomena of the Alpes maritimes.”

The president announced the receipt of a written communication
from MM. Lohest and Forir on “The method of numbered notation of
terranes.” ;

M. Stanislas Meunier. “The structure of the diluvium’ of the
Seine.”

The Secretary-General resuméd a note from MW. Hull on “Subocean-
ic terraces and valleys of the western rivers of Europe.” Also a note
from

M. Huddleston, on “The eastern border of the Atlantic.”

M. E. A. Martel. ‘The general geological and hydrological results
of the subterranean explorations which the author has undertaken
since 1888.”

M. G. Dollfus. “The last geological phenomena of which the
Seine and Loire have been the theater.” :

The late congress is pledged to publish before the expira-
tion of the year a volume containing not only the transactions
but important memoirs accompanied by fine illustrations.

ee ee

PLATE XXVIII.

THE AMERICAN GEOLOGIST, VOL. RS VILL

Sis
ee

rk PaALEozoIc oF MISSOURI.

M THE UPPE

FRO

OSSILS

The Upper Palaeozoic Fossils of Missourt.—Rowley. 343

TWO NEW GENERA AND SOME NEW SPECIES OF
FOSSILS FROM THE UPPER PALAEOZOIC
- ROCKS OF MISSOURI.

By R. R. ROWLEY, Louisiana, Mo.
PLATE XXVIII.

It is our purpose here first to discuss two little groups of
blastoids of which scarcely anything is known to the general
student of this class of organisms, since they are not only very
limited in their distribution, but even locally reckoned among
the rarities.

Of group one, the first mention is probably to be found in
Dr. Shumard’s description of Pentremites roemeri in the old
“Missouri Geological Survey, I and II Reports, 1855.” Imper-
fect as the description is and poor as the figures are, the author
had before him a specimen of what has since been described
as Granatocrinus sampsoni. It was hardly a medium sized in-
dividual and without surface markings, but with the rather
large interradial (deltoid) and distinctly convex base. (I re-
fer to his figure 2a. Figs. 2b, 2c and 2d represent another and
quite distinct thing. )

Along with his figure of Granatocrinus sampsoni, Dr. Hani-
bach figures one of Dr. Shumard’s specimens, but it is certainly
specimen no. 2 (2b, 2c, 2d as above) and can hardly stand for
G. roemeri.

The type of the latter species came from the Chouteau lime-
stone of Providence, Boone Co. Later collectors have found
this form near Sedalia, Pettis Co., and in the Kinderhook beds
at Osceola and Cedar Gap. The author of this paper has
found it at both of the latter places and has obtained specimens
of it from the other places mentioned.

The next species of the group brought to the notice of nat-
uralists is the Codonites inopinatus, passing over the problem-
atical Pentremites neglectus, too poorly defined and ill figured
to be able to be identified even generically.

Codonites inopinatus was figured and described in the
Kansas City Scientist, July, 1891.

In the August number of the same journal and same year
the third species was defined and figured as Granatocrinus apla-
tus. Two more species will follow the generic description here.

344 The American Geologist. June, 1901.

This group of blastoids presents some striking characteristics,
and is further removed from Orbitremites (Granatocrinus )
than Cryptobastus is. The base is either level with the lower
ends of the ambulacra or decidedly convex. The basal plates
form a low broad cup, thus separating widely the lower ends of
the ambulacra. The interradials (deltoids) are rather large,
often quite a third of the length of the fossil, while the anal
plate is sometimes extravagantly produced upward to form a
hood over the anal opening and pushing out towards the center
so as to reduce the usual star-shaped central opening to a
lunule. The spiracles are small and, although known for
some time in Granatocrinus aplatus, have been discovered but
recently in Codonites inopinatus. They are hardly round in
any of the species and decidedly elongate in the last two men-
tioned species, thus approaching, as we have always suspected,
the slits of Orophocrinus.

The prominence of the radial or fork pieces along the
sutures, gives rise to elongate depressed triangles bordering
the ambulacra, and across these triangles the lines of ornamen-
tation run as on the deltoids, or interradials, recalling the side-
plate areas on Orophocrinus. The ambulacra are either even
with the surface of the radials and interradials or stand out
bead-like above them.

The tops of the radials at the common suture are generally
prominent and sometimes so much so as to give a strongly
pentagonal cross section and a decidedly Codaster-like appear-
ance to the specimen.

The ornamentation is either linear, sometimes very fine and
again cord-like in its coarseness, or toothed-linear and possibly
granulo-linear.

We propose for this little group the generic name of Lopho-
blastus in allusion to the crest-like hood over the anal opening,
and make Codomnites inopinatus the type species of the genus.
We offer the following generic diagnosis: Body conoidal,
elliptical or quite globose; ventral side generally convex, but
sometimes flat; base large, flat or decidedly convex ; deltoids or
interradials large, sometimes a third of the entire body length ;
radials or fork pieces from one-half to nearly three-fourths the
length of the whole body; ambulacra even with the radial lips
or above them; Spiracles ten in number and vary from punc-

The Upper Palaeozoic Fossils of Missourt.—Rowley. 345.

tures to slits; anal opening surrounded by an elevated rim and
often strong hood-like upper prolongation of the anal deltoid
or interradius ; ornamentation, fine lines, coarse cord-like folds,
or crenulated lines ; columnar cicatrix rather large, but the col-
umn is unknown, so also the pinules.. The central opening
above (ventral) confined to a lunular area and, in perfect speci-
mens, covered by an integument of small plates.

The genus begins in the Kinderhook or the so-called Lower
Chouteau beds and extends through the Lower Burlington.

Lophoblastus conoideus, n. sp.

PLATE XXVIII.
Fig. 1—Side view, two diameters, of a large specimen.
Fig. 2—Ventral view, two diameters, of another specimen.
Fig. 3—Side view of a large elliptical specimen, natural size.
Fig. 4—Side view of a specimen, probably of a different species.

Body small, conoidal or elliptical. Base large, convex and com-
posed of the usual three plates. Columnar scar medium in size and
excavated. Interradials from one-fourth to one-fifth the length of the
body. Radials more than half the length of the body. The lower ends
of the ambulacra project outward. The spiracles are round or slightly
elongate openings and the anal opening is rather large and with a less
pronounced hood than any of the other species, excepting Lophoblastus
roemert. The ornamentation is fine or coarse lines parallel with the
plate sutures. The elongate triangular areas bounding the ambulacra
as marginal parts of the radials are less pronounced than in the type
species.

The specimens of this species were collected from Upper
Chouteau beds, two and one-half miles northeast of Curry-
ville, Mo.

This fossil was figured along with Granatocrinus mutabiiis
under the impression that it belonged to the same species, but
better specimens lately obtained show the greatest difference

between them.
Lophoblastus marginulus, n. sp.

PLATE XXVIII.

Fig. 18.—Ventral view of a specimen with the central opening
covered by an arch of minute plates extending a little way
over the ambulacra.

Fig. 19.—Side view of the body of the type specimen, showing
the character of ornamentation and the little rim around the
stem base.

The collection contains four of these little blastoids. The base is
flat or a very little convex. The lower ends of the ambulacra are

346 The American Geologist. June, 220K.

separated by a rather broad base made up of the usual three pieces.
The columnar base is surrounded by a distinct rim, giving a slightly
concave surface for attachment. The radials (fork pieces) are hardly
more than half the greatest length of the body. The interradiais
(deltoids) are more than a third of the length of the body. The am-
bulacra are more convex than the radial and interradial borders and
the interambulacral areas are flat or concave and three of the four
specimens are decidedly pentangular in cross section but this may be
due in part to the fact that the test is very thin and the three speci-
mens in question may be a little misshapen, due to pressure.

There are ten elongate or slit-like spiracles and an anal opening
with a hood but less prominent than in L. aplatits.

There is no elevation above the general surface at the tops of the
radials as in L. opinatus but the ornamentation is the same as in that
species (fine longitudinal lines), the cross lines of the deltoids con-
tinuing down the sides of the ambulacra as elongate triangles on the
radials to the very end of the ambulacra. The mid-interambulacral
triangular areas of the radials are crossed longitudinally by fine lines.
The type specimen is 7% mm. long and about 7 mm. wide. The
basal rim is a little over 2 mm. wide.

This blastoid comes from the brown, earthy layer just over
the top of the fifth division of the Lower Burlington limestone
and is associated with L. aplatus, Aorocrinus wachsmuthi,
Agaricocrinus planoconversus and Cactocrinus springert.
Hart’s and Pratt’s Quarries, Louisiana, Mo.

An average specimen of Lophoblastus conoideus is about
4 mm. in length by 4 mm in breadth. A large specimen 6mm.
in length by 4%mm. in breadth. A small specimen 2%mm. in
length by 3mm. in breadth.

The species of this genus at present known are,
Lophoblastus inopinatus, Lower Burlington limestone.
Lophoblastus aplatus, near top of Lower Burlington
limestone.

Lophoblastus conoideus, top of Choteau limestone.

Lophoblastus marginulus, top of Lower Burlington
limestone.

Lophoblastus roemert, Kinderhook or Lower Chouteau
limestone.

Lophoblastus (?) neglectus, Lower Burlington limestone.

The other group embraces three already described species

and a new one here figured and described for the first time.
Granatocrinus magnibasis was defined in the October, 1895
number of the AMERICAN GeEoLoaist, G. piriformis in the Aug-

The Upper Palaeozoic Fossils of Missourt.—Rowley. 347

ust, 1891, number of the Kansas City Scientist, and G. stella
in the February, 1900, number of the AMERICAN GEOLOGIST, _

We propose for this group the generic name Carpenterc-
blastus, as a slight tribute to our friend the late Dr. P. Herbert
Carpenter, of Eton College, England, and take for the type
species Granatocrinus magnibasis. The distinguishing charac-
ters of the new genus are sunken ventral surface; narrow, ele-
vated ambulacra; broad, convex basal disk; coarse, cord-like
ornamentation, and usually distorted appearance; rather small
deltoids, eight small rounded spiracles (two more are probably
confluent with the anal opening), and a small anal opening.
None but the young of C. magnibasis have symmetrical shapes,
while most of the specimens of C. stella are similarly and singu-
larly misshapen, the only one preserving the test, however, is
quite regular in outline. C. stella differs much from the other
species in the free ends of the ambulacra and consequent great
prominence of the base. The new species is represented by a
single specimen and that is in a crushed condition. It will be
known as,

Carpenteroblastus pentagonus, n. sp.

PLATE XXVIII.
Figs. 26 and 27.—Side and ventral views of the type specimen.

This little blastoid is about 6 mm. long by 5% mm. broad; has
small deltoids, long fork pieces and a flat, not large base; the ventral
side is concave. The spiracles are small, round and the anal opening
is inconspicuous. The ambulacra are narrow and convex beyond the
radial edges. The interambulacral areas are flat. The ornamentation
is hardly noticeable on the type specimen.

This rare bastoid comes from the same horizon as Lopho-
blastus aplatus and L. marginulus (top of the fifth division of
the Lower Burlington limestone) at Louisiana, Mo.

The species of this genus at present known are,

Carpenteroblastus magnibasis, base of Upper Burlington

limestone.

Carpenteroblastus piriformis, Upper Burlington lime-
stone.

Carpenteroblastus stella, base of Upper Burlington lime-
stone.

Carpenteroblastus pentagonus, top of fifth division Lower
Burlington limestone.

348 The American Geologist. Jane, Aavae

Aorocrinus wachsmuthi, n. sp.
PLATE XXVIII.

Fig. 38.—Side view of the type specimen, natural size.

This little crinoid has nodose calyx plates and blunt spinose ven-
tral plates. The central dome spine, so conspicuous in Dorycrinus is
represented by a nodose plate in this species. The basal plates form
a low rim about the top of the column. The first radials are very
nodose and about as long as wide. The second radials are smaller,
quadrangular pieces. The third plate in the radial series is a bifur-
cating piece and five-sided, and a little smaller than the second radial.
The interradials consist of one large noduse plate, upon which rest
two flattened plates above. The anal interradial area is filled by a
large plate in line with the first radials and a little larger than them,
supporting three smaller nodose plates above and resting on the latter
in turn are three smaller flat plates. The anal opening is on a wart-
like prominence. Three of the arm lobes give off two arms each
while the right and left anal lobes give off three each, making 12 arms
in all. The-stem base is very small and round.

We are glad to name this pretty little species for the late Charles
Wachsmuth of Burlington, joint author with Mr. Frank Spring-
er of the genus Aorocrinus.

This crinoid is found associated with Lophoblastus aplatus
and another Aorocrinus, apparently a variety of A. parva, near
the top of the fifth division of the Lower Burlington limestone
at Louisiana, Mo.

In our notes on the “Fauna of the Burlington Limestone at
Louisiana, Mo.,”” AMERICAN GEOLOGIST, Vol. XX VI, October,
1900, page 247, we mentioned a specimen of Schizoblastus sayi
with a short proboscis. We here figure this little specimen to
show this feature. Another specimen has since been found
showing the same structure. Figs. 15 and 16; the latter is an
enlarged view.

Fig. 30 is a side view of a splendid body of Cactocrinus
Springeri, a crinoid figured and described by the author in the
February, 1900, AMERICAN GEOLOGIST, as Batocrinus springer.

Fig. 31 is a large body, somewhat crushed, with three entire
arms and parts of three others. The great ventral tube is pre-
served to the arm tips and furnished with spines. The arms are
traversed longitudinally by short spiny nodes in rows. Asso-
ciated with these crinoids are spiny stems which, doubtless,
belonged to this species.

The Upper Palaeozoic Fossils of Missourt.—Rowley. 349

'Axophyllum ? alleni, n. sp.

PLATE XXVIII.
Figs. 32, 33, 34.—Side and ventral views of the largest specimen
Fig. 35.—Side view of a smaller specimen from Weston, Mo.
All drawn natural size.

The specimens of this species are short and broad, with the top of
the lamellae arched and above the epithecal covering of the outside,
even more pronounced than in Microcyclus. The lamellae or septa
number about sixty (60) and are rather crowded. The central boss
or columella of the shallow cup is strong, rounded and low, or trian-
gular, and is formed of the upturned inner edges of the lamellae or
septa. The cups show no other feature than those mentioned. The
outer surface or epithecal covering is considerably wrinkled and folded.
The base is acute and with or without radicular appendages.

Its distinguishing characters are the shallow cup, upper
edges of the septa arched above the outer epithecal covering,
shallow almost discoidal outline, short but stout columella.

It comes from the Upper Coal Measures of Northwestern
Missouri. . Specimen, figure 35, is from Weston.

The specific name is in honor of Mr. Thomas W. Allen, of
St. Joseph, Mo., an excellent collector in the Upper Coal Meas-
ures of western Missouri and one to whom the author is in-
debted for many favors.

Leptopora ramosa, n. sp.

PLATE XXVIII.
Fig. 36.—Side view of the type specimen, natural size.

Two specimens of this peculiar coral are in the author’s collection
and both are pointed below and expand above by the multiplication
of stems from the parent stalk, due to lateral gemmation. The coral-
ites are more or less round, very rugose and irregular in shape. The
cups are very shallow and where the sides and bottoms are weathered,
appear cellular. No septa are visible and are probably wanting, but
placenta are probably present as in L. placenta, although not seen in
the types.

This species occurs in the Chouteau limestone, east of Cur-
ryville, Mo., associated with Leptopora placenta and other cor-
als.

Leptopora procera, n. sp.

PLATE XXVIII.
Fig. 37—Side view of the type specimen, natural size.
The base of this coral differs but little from Leptopora placenta,
being flattened and with large shallow cups and a very wrinkled and
rugose epithecal under surface but in producing tall crowded stems

350 ‘The American Geologist. Jane

above by calicular budding, it differs from all the species of Lepto-
pora with which the author is acquainted. The stems spring from the
shallow cups below, are more or less round, very rugose and distorted
and, crowding together at the top, the otherwise round cups become
polygonal. From the calyx of one of the stems three small stems
arise. No septa are observable nor are placenta, but the latter are
‘surely present. The cups are shallow and are pitted or cellular in
appearance.

The fine specimen figured was obtained from the Chouteau
limestone at Annada, Mo.

Trigeria? curriei, n. sp.
PLATE XXVIII.

Figs. 40, 41, 42—Views of the brachial and ventral valves and
the front of the shell, respectively, twice natural size or two
diameters.

Shell longer than wide, plicated but with the plications more or less
obsolete, except near the front of the shell. Young individuals, how-
ever, are plicate throughout. The beak of the pedical valve is rather
long and pointed with a triangular area beneath it and a delicate tri-
angular foramen. Nothing is known of the inside of the shell. The
shells vary from 1%mm. to 6 mm. in length and from 1 mm. to 6
mm. in width. The specimen figured is 5 mm. by 4 mm. (length
and breadth.) There is a slight sinus at the front margin of the
brachial valve and sometimes one on the pedicel valve also. It is
rather a rare form in the Louisiana (Lithographic) limestone at
Louisiana, Mo. It is obtained, among other small forms, by washing
the clay from between the limestone layers.

This little brachiopod is named specifically for Rev. H. Cur-
rie, of Thedford, Ontario, an excellent collector in the Hamil-
ton group and a most obliging scientist.

Dielasma? pediculus, n. sp.
PLATE XXVIII.
Figs. 43, 44, 45.—Brachial, pedicel and front views of a large
specimen, two diameters.

Length of a large specimen 4%, width 3% mm.

This little shell is smooth, rather flat, elongate, with a rather long
pedicel beak, the end of which is perforate. It occurs abundantly in the
clay seams of the limestone and is obtained by washing the soft ma-
terial. It is found associated with the above species, Ambocoelia

minuta and Chonetes geniculata in the Louisiana limestone at Louis-
iana, Mo.

Nucleospira barrisi? (white.)

PLATE XXVIII.
Figs. 46, 47, 48—Three views of the brachiopod, natural size, as
it occurs in the Louisiana (Lithographic) limestone at Louisiana, Mo.

The Upper Palaeozoic Fossils of Missouri.—Rowley. 351

It is not plentiful. There is some doubt as to the correctness of the
specific reference.

Cyrtolites bennetti, n. sp.
PLATE XXVIII.
Figs. 61 and 62——Front and side views of the type, natural size.

The aperture of this shell is elongate, heart shaped. There is a
mid-dorsal fold and the strong lateral lines of ornamentation curve
sharply toward this fold. The inner whorls are hidden by the outer.
This shell is 74% mm. wide and is very rare. It is named for my
friend, Rev. John Bennett, of Kansas City, Kan.
_ It occurs about the middle of the Lower Burlington limestone at
Louisiana, Mo.

Spirorbis? dubius, n. sp.
PLATE XXVIII.
Figs. 59, 60.—Two views of the type specimen, natural Size.

This little shell was free and has no appearance of ever having been
attached.

It is composed of three irregular whorls, more or less distorted and
crossed by sharp ridge-like lines. It coils loosely. This species is al-
most certainly not Spirorbis but its generic relations are doubtful and
for the present we leave it under Spirorbis. It is 5 mm. wide.

It comes from near the middle of the Lower Burlington limestone
at Louisiana, Mo.

Amplexus vermicularis, n. sp.
PLATE XXVIII.
Fig. 51.—Side view showing nearly the entire length, natural size.
Fig. 52—Another view showing the contracted cup, natural size.

This peculiar fossil has the external appearance of Amplexus but
despite the excellent preservation of the type specimen, the septa are
not visible through the epithecal covering and are to be seen only on a
weathered spot, and, doubtless, are merely raised lines along the inner
side of the outer wall.

The external surface is beautifully ornamented by irregular cross
ridges and crowded lines of growth. Placenta are, doubtless, present
but not seen in the type specimen.

The example figured is entire, rather elongate, distorted and con-
tracted in places, yet gradually enlarging toward the front. The
strangest feature of the type specimen is its contracted calix, giving
the appearance of a second end for attachment and no open cup.
The contraction begins about 1-3 of an inch from the anterior end and
is almost closed at the front. Were it entirely closed the question
might be asked, can this be an opercutate coral? Other specimens ap-
parently of the same species but less robust and more elongate, have
fine crowded septa but hardly developed beyond the appearance of
raised lines and with placenta crossing the central open space at irreg-
ular intervals without curvature. This fine coral is from the third di-
vision of the Lower Burlington limestone at Louisiana, Mo.

352 The American Geologist. June, 1901.

Amplexus radigerus, n. sp.
PLATE XXVIII.
Fig. 39.—Side view of the type, natural size.

Coral elongate, differing little in cross diameter, except where the
stem makes rapid contractions.

Shape irregular, often abruptly bending to the right or left. The
cup is not clean in the type specimen, but is apparently deep and the
septa poorly developed, but seen on the surface as fine crowded lines.
On the inner side of the surface wall they are more pronounced than in
A. vermicularis. Cross lines of growth and ridges of distortion gird
the exterior. Tabulae at irregular intervals cross the central area. A
few short radicular appendages occur along the lower half of the coral.

Another Amplexus, probably distinct, with little greater diameter
than this form, is often found several inches long and apparently in-
complete, alternately contracted and exponded, but without radicular
appendages.

This coral comes from the third division of the Lower Bur-
lington limestone at Louisiana, Mo.

Coleophyllum? greeni, n. sp.
PLATE XXVIII.
Fig. 53.—Side view of a nearly perfect coral, natural size.
Figs. 54, 55, 56:—Side views of other specimens, weathered in
such a way as to show structural features, natural size.

This coral is elongated, curved and without septa (lamellae). The
cup is shallow. The entire fossil is made up of a series of invaginated
tabulae, as seen on the weathered specimens. The outer surface is
comparatively smooth except near the calix where the edges of the
tabulae remind one somewhat of Cystiphyllum.

The specimens are from the Upper Chouteau limestone,
three miles northeast of Curryville, Mo.

Aulopora longi, n. sp.
PLATE XXVIII.
Fig. 57.—Side view of a large stem, natural size.

This is a slender, elongate species. The tubules are very long with
the oral portion rapidly expanding. Each coralite comes off from the
one below it in such a way as to give a zigzag appearance to the stem.
This species is probably attached at the base but never along the side.

It occurs both in the Lower and the Upper Burlington lime-
stones at Louisiana. Some specimens are quite two inches long.
The specimen figured is from the base of the Upper Burlington
limestone. It is a much more delicate species than A. gracilis,
We are glad to name this coral for Mr. F. R. Long, of Louisi-
ana, Mo.

Aulopora amplexa, n. sp.
PLATE XXVIII.
Fig. 58.—View of a colony surrounding joints of a Platycrinus
stem, natural size.

The Upper Palaeozoic Fossils of Missouri.—Rowley. 353

This is a much stouter coral than either A. longi or A. gracilis but
near to the latter, except in its manner of growth. The colonies are
always found surrounding stem joints of crinoids, especially Platy-
crinus and, sometimes, as in the type specimen, between two stem
joints, pushing them apart and surrounding them. The tubules are
rather large, short and little expanded at the orifices.

Stem joints of Platycrinus are often found in the Burlington lime-
stone with from two to four or five conical holes reaching almost or
quite to the center of the stem and sometimes showing remnants of a
tubular form filling each hole. Is this our Aulopora?

This species comes from the base of the Upper Burlington

limestone, at Louisiana, Mo.

EXPLANATION OF PLATE XXVIII.
Lophoblastus conoideus, n. sp.
Fig. 1. Type specimen. Side view x2.
Fig. 2. Ventral view of another specimen, showing the anal opening
and the ten small, round spiracles x2.
Fig. 3. Side view of a specimen, more globose and with finer orna-
mentation XT.
Fig. 4. Side view of a broad specimen apparently granulo-striate xt.
Fig. 17. Side view of a young specimen, natural size.
Lophoblastus inopinatus Rowley & Hare.
Fig. 5. Ventral view of a specimen showing the anal opening and the
short slit-like sniracles x2.
Figs. 6 and 7. Side and ventral views of a specimen with a strong
pentagonal outline at the top of the radials, natural size.
Fig. 8. An elongate specimen, side view, showing the shape and great
hight of the anal hood. Natural size.
Lophoblastus aplatus Rowley & Hare.

Fig. 9. Side view of a medium sized specimen, natural size.

Fig. 10. Side view of a larger specimen, showing ornamentation and
the hight and shane of the anal hood, natural size.

Fig. 11. Ventral view of a specimen to show the anal opening and
elongate spiracles, x2.

Fig. 12. Side view of the top of a specimen to show the hood and
anal onening, x2.

Lophoblastus roemeri_ Shumard.

Fig. 13. Side view of a medium sized specimen, showing the coarse
character of ornamentation, natural size.

Fig. 14. Side view of an elongate specimen with flat base, natural size.

Lophoblastus marginulus, n. sp.

Fig. 18. Ventral view cf a plump specimen, showing the central open-
ing closed by a covering of small plates that extend out for a
short distance over the ambulacra. Natural size.

Fig. 19. Side view of the type to show the beautiful ornamentation,
broad base and the expanded columnar disk or rim. Natural
size.

354

The American Geologist. ee ded ~~

Carpenteroblastus magnibasis Rowley.

. 20. Side view of a specimen to show the character of ornamenta-

Monn. cL:

. 21. Basal view of the same, natural size.

22 and 23. Ventral and side views of a natural cast from chert
to show the great thickness of the test about the ambulacra
and the usual unsymmetrical character of the species. Natural
size.

. 29. Ventral view of a smaller specimen, preserving the test and

showing the spiracles and anal opening, natural size.

Carpenteroblastus stella Rowley.

. 24. Side view of the type, showing specific characters, natural size.
. 25. Ventral view to show the anal opening and spiracles, natural

size.
Carpenteroblastus pentalobus, n. sp.
'

26 and 27. Side and ventral views of the type, natural size. (Spec-
men somewhat crushed. )

Schizoblastus sayi Shumard.

. 15. Side view of an undersized specimen, preserving the base of a

little ventral tube. Natural size.

. 16. Top of the same specimen, enlarged to four diameters, to show

the plates in the tube.

. 28. Ventral view of a somewhat larger specimen, having the cen-

tral opening closed by a covering of minute plates, passing out
over the ambulacra for a short distance. Natural size.

Aorocrinus wachsmuthi, n. sp.

. 38. Side view of the type specimen. Natural size.

Cactocrinus springeri Rowley.

. 30. Side view of a fine body, natural size. .
ig. 31. A specimen showing the heavy spinose ventral tube and the

heavy nodose arms, XI. -

. 49 and 50. The column of this crinoid, end and side views, nat-

ural size. *

Leptopora ramosa, n. sp.

. 36. Side view of the type specimen, natural size.

Leptopora procera, n. sp.

. 37. Side view of the type specimen, natural size.

Axophyllum ? alleni, n. sp.

g. 32 Side view of the largest specimen, natural size.

. 33. Same with the calix turned a little toward the observer.

. 34. Same, calix view.

. 35. Side view of a smaller specimen. All figures of this species,

natural size.

Amplexus radigerus, n. sp.

. 39. Side view of the type specimen, natural size.

The Upper Palaeozoic Fossils of Missourt.—Rowley. 355

Amplexus vermicularis, n. sp.

Fig. 51. Side view, natural size, showing nearly the entire length.

Fig. 52. Another view showing the contracted cup, natural size.
Chonophyllum greenei, n. sp.

Fig. 53. Side view of an unworn and nearly entire specimen, natural

size.
Figs. 54, 55, 50. Side views of worn specimens, showing the invaginat-
ed tabule.

Aulopora longi, n. sp.
Fig. 57. Side view of the type specimen, natural size.

Aulopora amplexa, n. sp.
Fig. 58. A specimen surrounding a platycrinus stem joint, natural size.
Spirorbis? dubius, n. sp.
Figs. 59 and 60. Two views of this peculiar fossil, natural size.
Cyrtolites bennetti, n. sp.
Figs. 61 and 62. Front and side views of the type specimen, natural
size.
Trigeria ? currici, n. sp.
Figs. 40, 41, 42. Brachial, pedicel, and front views of a large specimen.
noon
Dielasma ? pediculus, n. sp.
Figs. 43, 44, 45. Brachial, pedicel and front views, x2.
Nucleospira barrisi? White.

Figs. 46, 47, 48. Pedicel, brachial and front views, natural size. ,

ORE FORMATION ON THE HYPOTHESIS OF CON-
CENTRATION THROUGH SURFACE
DECOMPOSITION.

By CHARLES R. KEYEs, Des Moines, Iowa.

In seeking a suitable explanation for the localization of ore
materials from an assumed generally diffused condition in the
country rock, a number of recent writers have leaned towards
the idea that through the surface decomposition and degrada-
tion of the land the heavy materials in large part remain behind
and tend to concentrate into ore deposits, the extent of which
in any particular instance is to be regarded in a measure pro-
portional to the amount of general erosion which that region
has undergone.

This hypothesis has received special attention in the consid-
eration of the lead and zine deposits of the Mississippi valley.

356 The American Geologist. Juse tee

Its application, however, has not been confined to this region.
It has been extendéd to other mining districts, even those in
which typical fissure veins abound.

Since the most advanced conceptions regarding the nature
of erosion have gained such wide hold among geologists, ore
students have seized with avidity upon some of these principles
as furnishing a long sought for solution to the manner of many
concentrations of ore bodies. The attractive features of the
hypothesis are many. But objections have not been so obvious,,
and have not generally presented themselves. These last men-
tioned phases of the subject have entirely escaped the notice of
mining engineers and special students of ores from the mining
side. To geologists who have given geographic development
special attention, the objections appear formidable, and in
many instances unsurmountable.

Winslow* formally states the hypothesis when he says that
it ‘‘starts with the proposition that the metalliferous minerals
originally existed in the Archean rocks, either in a disseminat-
ed condition or in veins. With the decay of these early rocks,
the minerals became diffused through later-formed sediments,
this diffusion being quite uniform over contiguous areas. Suc-
cessive decaying of successively formed rocks simply resulted
in a transfer of these minerals.’’ Accordingly, the concentra-
tion process was entirely subsequent to the period of rock for-
mation. “It is, primarily, a result of great and long-continued
surface decay of the rocks; and, secondarily, the result of the
presence of local favorable physical and chemical conditions.”

This general statement presents numerous slight modifica-
tions with different writers. Its advocates agree that the dif-
fused ore-materials are, as degradation of the land goes on,
carried downward to lower and lower levels, the metal-accu-
mulating zone retaining always a constant relation to the
ground surface. From this proposition two main phases pro-
ceed. One would retain the ore materials in a diffused condi-
tion; the other in a concentrated form, or as an enrichment of
~ the lower zones.

The principles of geologic geography demonstrate beyond
all doubt that lands elevated are worn down to near sea-level
‘with far greater rapidity than has been generally supposed.

* Missouri Geol. Sur., vol. vii, p. 477, 1894.

Ore Formation by Surface Decomposition.—Keyes. 357

The fact that in many localities enormous denudation has taken
place in the past, has been for a long time widely recognized.
But that profound erosion, thousands of feet in depth, mav
easily take place in a single geological epoch or period, instead
of during one or several long geological eras is a proposition
which has not been sc universally appreciated.

If we apply to any particular locality either phase of the
hypothesis that generally diffused ore materials are concentrat-
ed through surface decomposition of the country rocks, we
should expect to readily find abundant facts in substantiation.
Either the ore materials of a region should give evidence of
unusual original accumulation through the phenomena of local
sedimentation; or the concentration should be about propor-
tional to the amount of erosion. ‘

With regard to the first of these propositions, students of
ores are now pretty well in agreement that such factors as
oceanic currents can no longer be considered as appreciable fac-
tors directly affecting the localization of ore deposition through
solution. Besides, there are so many secondary factors enter-
ing into the problem, that even if the truth of the proposition
be assumed, it would be utterly impossible to adduce proofs,
so completely would they be obscured by attendant features. In
the light of recent geographic and geologic research, all theo-
retical deductions appear to militate against the possibility of
such conditions.

The second proposition presents some objections not met
with in the first. The theoretical deductions are conclusive. The
practical demonstrations present no very great difficulties. In
the case of the Ozark region, of which a special example has
been made, the facts are singularly against the hypothesis ad-
vanced.

The analyses made by Robertson* of Missouri rocks, show
the presence of lead, zinc and copper in minute quantities.
While the number of determinations made is far too small to
enable any broad generalizations to be stated, it is significant
that those rocks taken from the mining localities contain a very
much higher percentage of metallic contents than those collect-
ed from localities remote from ore bodies. The inference would
naturally be that the present difference in the amounts of the

* Missouri Geol. Sur., vol. vii, p. 479, 1894.

358 The American Geologist. June; AOR

metals in these rocks is due largely to the same concentration
which produced the existing ore bodies.

The analyses mentioned were made for the express purpose
of supplying evidence to the theory of the general diffusion of
metals in rock masses. Winslow’s hypothesis* is that in the
Ozark region the rocks have suffered enormous denudation,
and consequently the metallic substances that were diffused

through the portion eroded have settled down, and have been _

redeposited in the constantly lowering zone at or near the
ground surface.

Curiously enough for this hypothesis, along the summit of
the Ozark dome, where decomposition and denudation have
been greatest (by some 4,000 feet or more than at the margins )
there ate practically no ore bodies of consequence. The rich-
est and most extensive deposits are at the very base of the up-
lift, in a district which has not only suffered a minimum amount
of denudation, but which has not been removed more than the
northern part of the state of Missouri, where no deposits what-
ever occur.

In a very localized form the same hypothesis is claimed
to be applicable to true fissure veins. This phase of the subject
has been lately emphasized by Weed? in the consideration of
the gold and silver deposits of Montana. This author also calls
special attention to the ore bodies of the Australian Broken Hill
Consol mine of New South Wales, as described by Smith,# and
to the Aspen district of Colorado, described by Spurr.§ He
says: “Active degradation favors the accumulation of enrich-
ments, while prolonged degradation of a region, resulting from
physiographic revolutions, may result in successive migrations
of material and the accumulation in a relatively shallow zone
of the metals derived from many hundreds, and possibly thou-
sands, of feet of the vein worn away in the degradation
of the land. Climatic conditions, rainfall or aridity, warmth
and rapid alteration of vein fracture are agents affecting sur-
face weathering, and hence, also, enrichment.

“Active degradation of a region, that is, rapid weathering,
favors enrichment by the quigkness with which it removes the
upper already leached part of the vein, so that a large amount

Missouri Geol. Sur., vol. vii, p. 469, 1894.

Trans. American Inst. Min. Eng., vol. xxx, 1900.
Trans. American Inst. Min. Eng., vol. xxvii p. 69, 1896.
U. S. Geol. Surv., Mon. xxxi, 1898.

nib *

‘Ore Formation by Surface Decomposition.—Keyes. 359

of the vein matter is lixiviated in a given time than would re-
sult from slower wasting of the land. Such enrichments are
favored by high altitudes. Moreover, the mountainous re-
gions are those in which secondary fractures are most apt to
be found.”

Blake’s observations* on the formation of the lead and zinc
deposits of the Wisconsin district have an import similar to
that of Winslow’s for Missouri.

Of like suggestion is Winchell’s viewt regarding the Wis-
consin lead deposits and the Minnesota iron ores. This au-
thor regards the Cretaceous strata as having extended over the
whole of the upper Mississippi valley region and in their re-
moval to have allowed the ore materials to lodge in the porous
and gashed Silurian rocks beneath.

These special examples have been noted in this connection
for the reason that in all there is the same effort to seek an
adequate and direct source for the ore bodies. All start with
the assumption that the present ore bodies were derived from
the ore materials-that had settled downward as the great rock
masses above were removed through erosion. In other words,
the existing ore bodies of the region mentioned are claimed to
be deposits the formation of which has depended wholly or
largely upon the general metallic content of the country rock
once existing above the present ground surface of the respec-
tive districts.

In none of these cases is it believed that the conclusions
reached regarding the local source of the ore materials are
either warranted by the arguments adduced, the facts as thev
are presented in the field, or the general geological conditions
known to be prevalent in ore-producing regions.

In the case of the Ozark region, we have unusually com-
plete data regarding the geological times of rapid erosion and
the periods of peneplanation. There is abundant evidence
showing that immediately after the deposition of the Lower
Carboniferous rocks—the country rock of the southwest Mis-
souri zine district—the Ozark region was not the highland it
now is. Between the time when the last Lower Carboniferous
limestones were deposited and that when the first Coal Meas-
ures of Missouri were laid down, the strata were tilted and se

* Trans. American Inst. Min. Eng., vol. xxii, p. 628, 1894.
+ Minnesota Geol. Sur., Bull. 6, p. 153, 1891.

360 The American Geologist. _ Jae ee

profoundly eroded as to expose all formations down to the
Cambrian ; while in the south, in Arkansas, where sedimentation
‘went on uninterruptedly, strata to a thickness of 20,000 feet ac-
cumulated. Along the horizon of this peneplain there is no
evidence of notable deposits of ores of any kind.

Beds belonging to the upper part of the Coal Measures
are now known to occur on the highest parts of the present
Ozark dome. Small doubt therefore exists as to the extension

of the Coal Measures (Des Moines and Missouri series) en--

tirely over the region occupied by the great uplift. This is
also, according to our best knowledge on the subject, probably
true of the Cretaceous strata. Before, however, the deposits
of the latter were formed another long period of erosion inter-
vened. Yet in the known remnants of the peneplain which
was formed at that time no signs of the existence of ore bodies
are found.

Again, when the Ozark region was bowed up and planed
off in Tertiary time down to the pre-Cambrian basement, no
indications are presented that the peneplain which is the pres-
ent general upland surface of the dome, is a horizon that is a
special ore-bearing level. As already stated, it is in the central
part where degradation has been greatest that ore deposition
has been least.

We are forced to the conclusion, at least so far as the
Ozark region is concerned, that degradation and surface de-
composition even though so profound as to remove thousands
of feet of rock, do not tend to concentrate whatever diffused
metallic content the strata may contain. While profound sur-
face decomposition is an important factor in the formation of
ore deposits, by itself it produces no effect in this direction.
There must also be special geological structures and speciai
geological conditions always present before the localization of
ore material is possible.

Without attempting to discuss or furnish detailed evidence

at this time, it may be in this connection granted that most
rocks actually do at all time contain in a diffused condition
ample supplies of most common metals to furnish materials for
the richest of ore deposits, that subterranean waters are con-
stantly transferring laterally from one point to another metallic
substances along with many others which are not ore-forming,

Ore Formation by Surface Decomposition.—Keyes. 361

and that the leached substances from near the ground surface
are being carried through faults, joints and cracks downward
to lower levels. In addition to all this there must be special
local geological conditions to be satisfied before ore bodies
can begin to form.

There is a parallel example in the case of petroleum. Next
to water, we now know that rock-oil is perhaps the most abund-
ant substance circulating in the earth’s crust. The Waterlime
formation of Ohio and certain dolomytes of the Mississipp:
valley contain in each 500 feet of thickness upwards of 2,500,-
000 barrels of oil to the square mile. The oil contained in only
three townships would thus be more than the total amount
which has up to the present time been taken out of Pennsylva-
nia and New York fields. In order to have an area econom-
ically productive a peculiar association of geological structures
and conditions must exist. There must be a reservoir in the
form of a porous or cavernous bed, a non-porous cover as af-
forded by a shale stratum, and a bowing up of the strata such
as is presented by an anticline. The absence of any one of these
precludes the accumulation of oil bodies. So in connection
with the ores the conditions and structures may all be present
but one and yet there will be a failure of ore bodies.

In the more special case, in which a concentration has al-
ready well progressed, as presented by a mineral vein or a
lean ore vein, where enrichment has taken place below the
zone of weathering through downward flowing currents, it
does not appear probable that the ores from the upper part of
a vein can be considered as furnishing the enriching materials
for the lower portion. As openings, fissures of any kind are
at best very ephemeral in character. In no instance can they
be regarded as forming open water passages for any consider-
able period of time. They must be completely closed up long
before surface degradation has advanced to any appreciable
extent.

New fissures may open up in the rock, new fault move-
ments may take place, new cracks may be formed, through
which metalliferous solutions may find access to the old mineral
vein or lean ore sheet, but only in exceptional cases would ma-
terial from the upper part of a vein find lodgement lower down
in the same vein. The waters affecting the surface of an ore

362 The American Geologist. June, 1901

sheet would ordinarily carry the decomposed materials far
from the neighborhood.

The general metallic content carried by circulating waters
would doubtless accomplish the same result of secondary en-
richment of lean veins, but it would certainly be through other
openings than that in which the original vein was formed.

In the particular examples cited by Weed* of the Mollie
Gibson and Smuggler ore bodies and bonanzas, the enrichments
are along the lines of secondary faulting and the alterations are
only in the immediate vicinity of these later fractures. Many
other similar examples might be mentioned.

The immediate practical importance of the distinction is
perhaps not so great at the present time as is the fact that the
plausibility of the hypothesis at first glance being so evident
is likely to lead often to untrustworthy conclusions.

The conclusion seems inevitable that with the exception of
possibly a few isolated unimportant instances ore concentration
does not generally take place through surface decomposition
of rock masses, in areas such as the Ozark lead and zinc re-
gion. As in the case of petroleum, if it be assumed that ail
rocks at all times contain ample supplies of metallic salts in a
diffused condition sufficient for the most extensive ore de-
posits, and that the circulatory waters hold them at all times in
solution to a greater or less but adequate extent, these musi
be regarded general, always present conditions. But concen-
tration of metallic salts into ore bodies must be admitted to be
accomplished under special local conditions of geological struc-
ture, quite independent of all rock decomposition and _ land
degradation.

* Trans. Ametican Inst. ‘Min. Eng., vol.: Sy 1900.

Ss i

Gold and Other Minerals in Iowa.—Calvin. 303

CONCERNING THE OCCURRENCE OF GOLD AND
SOME OTHER MINERAL PRODUCTS IN IOWA.*

By SAMUEL CALVIN, Iowa City, Iowa.

It is a source of constant wonder and surprise that, not-
withstanding all that has been said and written, there are yet
persons of influence, intelligent beyond the average in all other
respects, who entertain the crudest conceivable notions con-
cerning the facts of geology and the distribution of mineral
resources. The highest natural gifts and the broadest schol-
arly training and business experience seem to be altogether
ineffectual, in the absence of some training in the principles
.of geology, to protect men from the most amazing fallacies
as to what may or may not be found below the surface of the
ground. Samples of yellow mica from decayed Kansan bowl-
ders, or iron pyrites from shales or limestones, are received al-
most weekly from persons who imagine they have discovered
gold in Iowa. Small flakes of brass worn from the working
parts of pumps or other farm machinery, are among the causes
which have led to repeated reports of discoveries of gold in a
region where not a single condition favorable to the presence
of the precious metal exists. Probably the most wild and un-
justifiable of all the crude beliefs respecting geological re-
sources is that which holds to the conviction that by going
deep enough the drill is sure to find something of value, no
matter at what point the work of boring is commenced. There
are numerous wise persons in every community, estimable, in-
fluential and in the highest degree public spirited, who are con-
vinced that the question, for example, of finding coal in their
special locality is simply a matter of the depth to which the ex-
plorations are carried. Rock oil and natural gas are recog-
nized as desirable products in every progressive community,
and every such community contains persons, in other respects
intelligent, who are ready to stake their own fortune and that
of their nearest friends on the belief that oil and gas are every-
where underneath the surface, and that their sources can be
tapped with the drill, provided only there is sufficient capital to
keep up the process of drilling long enough. :

*Advance sheets from the Reports of the Iowa Geological Survey, Vol. XI,
pp. 17-27.

364 The American Geologist. June, 1901

But is there no gold in Iowa? Men certainly have found
some. Coal occurs in certain localities in the state, why are
the chances not equally good for finding it in all other local-
ites? Why is it not a good business venture in Iowa to ex-
plore the depths of the earth for gas and oil, when fortunes
are made and cities are boomed by the discovery of these de-
sirable products in other states? Why is it not a proper func-
tion of the Geological Survey to bore test holes in different
localities in order to settle the question of the presence of oil and
gas beneath the surface? To answer these questions fully
would reqitire much space and would involve a discussion of
some of the most elementary principles of geology. Let me
try as briefly as possible to present the facts necessary to an un-
derstanding of these subjects for the benefit of the non-geolog-
ical reader.

Native gold, metallic gold, free gold—by whatever name it
may be designated—occurs chiefly under two conditions. First,
it is found in veins in the crystalline rocks. Such rocks are
generally very old; they are fundamental; they occur at the
surface in a broad belt around Hudson Bay—none of the new-
er or later formed rocks being present in that locality—and
they extend down into northern Michigan, northern Wisconsin
and northern Minnesota. They have been forced up near the
surface and have been subsequently exposed by erosion in all
mountain regions. As a rule, it is in mountain regions that
gold is associated with them, for it is here that they have been
fissured by the strains and movements which gave rise to the
mountains. Various minerals have been concentrated in the
fissures by circulating waters—the waters being more efficient

we sometimes find gold. Gold-bearing veins in the crystalline
rocks are the basis of all the lode mining; but it must be kept
in mind that only a very small proportion of all the veins re-
ferred to carry gold. Now there are no true crystalline rocks
anywhere near the surface in Iowa. All such rocks here are
deeply covered with newer rocks of sedimentary origin. These
sediments were laid down, one on the other, in slow and order-
ly succession, on ancient sea bottoms, in precisely the same way,
and of precisely the same materials as the beds of mud and sand
and limy ooze which are to-day accumulating on the marginal

if warm and alkaline—and among the minerals so concentrated —
ve

Gold and Other Minerals in Iowa.—Calvin. 365

bottoms of the modern seas.* Such rocks contain no gold-bear-
ing veins, and hence it must be obvious that there can be no
lode mining for gold in Iowa. In the second place, free gold
occurs in placer mines. Placer mines are simply sheets of dis-
integrated rock material which has been strewn over the sur-
face, usually along river valleys, by the action of flowing water.
The rocks of mountains decay and are worn away by air, storm
‘. waters, frosts and other agents ; the gold-bearing veins, if there
are any, decay with the rest; the gold is freed from the matrix
in which it was embedded, and the loose materials, gold and all,
are gradually washed down to lower levels. The placer miner
simply separates—by some convenient device—the gold from
the loose clay and sand and gravel with which it is accidentaily
associated. It must again be obvious that, except in regions
where there are gold-bearing veins, there can be no placer
mines worth considering. From all this it will be easy for any-
one to estimate the probability of finding gold in such a state as
Iowa.

In apparent contradiction of all that has just been said it
must be acknowledged that gold is occasionally washed out of
the sand banks and river gravels within the limits of our state.
Spread over the sedimentary rocks and forming our soils and
subsoils, are sheets of drift which were transported and dis-
tributed by glaciers coming from the north. Some of the ma-
terials forming the drift at any given point were carried long
distances, from away beyond the national boundary. In north-
ern Minnesota and on the other side of the boundary line, 1n
the Rainy Lake region, are quartz lodes carrying free gold.
The ice sheets brought disintegrated materials from this region,
as they did from all others over which they passed, and spread
them out as part of the drift of lowa. Some particles of gold
came with the rest, and it is possible occasionally to discover
some of them by panning carefully the loose surface materials.
A resolute, industrious man, working persistently year by year,
might possibly accumulate one or two dollars’ worth in the
course of a lifetime; but the business cannot be recommended
as a profitable means of employing one’s time. The resident
of Iowa who imagines he has discovered a gold mine on his
home farm is certainly basing his judgment on deceptive ap-
pearances of some kind.

306 The American Geologist. Junk, <P

To understand the situation in*respect to coal a few things
must be kept in mind. © First, as every miner knows, the coal
is interbedded with sedimentary rocks, usually with sandstones
‘and shales. Second, sedimentary rocks were laid down, one
on the other, one after the other, in slow succession ; and so the
history of rock deposition in lowa embraces a very long period
of time. This history is almost complete from a period earlier
than the introduction of life on the globe to times when land
plants and animals were well developed. Third, coal was
formed from land plants of certain types, the plants being pre-
served so as to be transformed into coal only under peculiar
and favoring conditions. Fourth, coal plants did not come in-
to existence until long after the beginning of the record pre-
served in the geological strata of Iowa. The older rocks,
therefore, can contain no coal, because they were laid down
long before any coal plants grew. All the rocks indicated on
the geological map, Plate II, in Volume X, as Algonkian, Cam-
brian, Ordovician, Silurian, Devonian, and Mississippian, are
older than any coal. The coal of Iowa occurs chiefly in the
Des Moines formation; a little is found in the Missourian. It
was while these two formations were in process of accumula-
tion, not before, that coal plants of sufficiently luxuriant growth
to count for anything existed in Iowa; and though these plants
were abundant, it was only in certain favored and comparative-
ly limited localities that the preservation of the plants took
place so as to form coal. The geological formations of lowa
lie one on the other somewhat like the shingles on a roof, ex-
cept that the oldest and first laid formations extend underneath
the rest all the way across the state. The older formations ap-
pear successively from beneath the latter in going from the
southwest toward the northeast. The Cambrian sandstones
that are found in the sides of the valleys near Lansing, lie far
below the surface at Des Moines. <A well bored at Des Moines
would pass, in the reverse order of their formation, through
all the older beds, and would finally reach the Cambrian at a
depth of about 1,600 feet. All these older beds, and all the indi-
vidual layers of them, are seen in order, one after the other, be-
tween Des Moines and Lansing; and so a drill hole at Des
Moines could reveal nothing of consequence that might not be
learned by careful investigation of the natural surface expos-

Gold and Other Minerals in Iowa.—Calvin. 367

ures in the region between Des Moines and the northeast cor-
ner of the state.* Explorations for coal in the Mississippian,
Devonian, Silurian, or older systems of rocks are foredoomed
to failure for the simple reason that these rocks were all com-
pleted before a single workable coal seam was deposited, some
of them before a single coal plant, or any terrestrial forms of
vegetation from which coal might be formed, had come into
existence. These formations all lie geologically below the
coal. If one could begin in the Mississippian or lower forma-
tions underneath Des Moines or in that vicinity, and bore up-
wards he might have some chance of striking coal. But boring
downwards in any of the formations referred to, whether un-
der Des Moines or at points where the older beds come to the
surface in the eastern part of the state, is going in the wrong
direction ; and the farther the boring is carried, the more hope-
less, becomes the search. There is positively no coal in any
parts of Iowa, which have formations older than the Des
Moines shales and sandstones as the surface rock. The find-
ing of coal is not a question of deep drill holes, but 1s one of
intelligent and thorough prospecting of geological deposits of
a particular age. If the operation is begun in any formation
older than the Des Moines, the drill may go through to Aus-
tralia or anywhere else without finding a speck of coal.
Petroleum and natural gas are like coal in one particular-—
they are derived from organic products. They are known to
have their origin in dark bituminous shale, in limestones, which
are in general of organic origin, in quantities of vegetable mat-
ter included in sandstones, in remains of forests buried in the
drift, in any accumulations of organic matter which have un-
dergone or are undergoing decay while hermetically sealed
from the atmosphere. The marsh gas, which is annually pro-
duced by the decay of vegetation at the bottom of ponds, af-
fords an illustration of the origin of one of the products we are
considering, familiar to almost every observant person. It
need scarcely be said, therefore, that rocks which are older than

*The Greenwood Park well at Des Moines has penetrated to the Cambrian
and has put to actual test the statements which any competent geologist
would have made in advance. All the broad details of that boring could have
been written out beforehand. The full record of the well, to the minutest de-
tails, is given in Norton's Artesian Wells of Iowa, Iowa Geol. Sur., Vol. VI, p.
294.et seq. Scores of other deep wells scattered throughout Iowa and confirm
ing all that would be inferred from studies of the superficial exposures, are de
scribed in the same volume.

368 The American Geologist. June, 1901,

the introduction of life on the globe can furnish neither gas
nor oil; and the fact that such rocks may be reached in Iowa at
no great depth makes it possible to explore the whole of the
‘possibly productive series with comparative ease. Owing to
their low specific gravity, oil and gas are displaced by descend-
ing waters and tend to rise toward the surface. They may,
therefore, be found at some distance above the beds in which
they are generated, but it would be very unusual to find them
lower down.

The seas were practically destitute of life when the Algon-
kian quartzytes at the base of the Iowa geological column were
laid down, and all rocks older than the quartzytes were formed
under conditions even less favorable. It may be very positive-
lv affirmed that explorations for oil or gas below the top of the
Algonkian are certain to be fruitless. Above the Algonkian
lies a body of Cambrian sediments—mostly sandstones—1,00o
feet in thickness. Life was far from abundant in Iowa during
the deposition of the Cambrian, though even if it had been
never so prolific, it would have counted for little, since sand-
stone is not a good conservator of the organic matter present

in the seas at the time of its accumulation. Sandstones are

good reservoirs for the storage of gas and oil after these prod-
ucts have been generated from some underlying productive
rock. But there is nothing below our Cambrian from which
gas or oil could be derived, and so the probability of finding
either below the top of the Cambrian sandstones is so small as
to be unworthy of consideration. Overlying the Cambrian are
two formations, the Oneota and the Saint Peter, equally as bar-
ren as anything below them. When the drill reaches the top
of the Saint Peter sandstone, it has practically passed through
and beyond all formations in which there is any possible hope
of finding the products under discussion. Next in ascending
order comes the Trenton limestone, a formation that was laid
down on a sea bottom fairly crowded with swarming forms of
life. This limestone is impure; it contains a large amount of
clay mixed either with the materials forming the layers o1
stone or laid down as beds of shale between the more stony lay-
ers. The Trenton formation was deposited under exceedingly
favorable conditions for making it a productive source of gas
and oil. It still contains large quantities of bituminous mat-

—_— == Pie ie

Gold and Other Minerals in Iowa.—Calvin. 369

ter which by the slow distillation always going on must yield
annually considerable volumes of gaseous or liquid hydrocar-
bons. At all the exposures of the lower Trenton, from Du-
buque northward, the dry shaly partings between the ledges of
limestone afford material so rich in bitumen that it is easily
lighted with a match; it burns freely and emits a strong oily
odor. Bituminous shale, precisely like that seen in the natural
“exposures, was brought up from the horizon of the Trenton
in the deep well at Washington, Iowa; it has been recognized
in other deep wells; the same shales, rich in bitumen, probably
underlies the greater part of the state.

If then a great amount of bitumen is stored up in the Tren-
ton limestone and is constantly evolving gas and oil by slow
distillation, why are not gas and oil wells as common in Iowa
as in the productive regions of Ohio and Indiana? Let it be
answered that something more than petroleum-bearing rock
is needed in order that oil may be obtained in quantities of
commercial importance. It has been estimated by professor
Orton that the rocks beneath the surface over a very large part
of Ohio contain at least 3,000,000 barrels of oil to the square
mile, and yet not one gallon of this can be secured by the drill
without the concurrence of at least two other conditions: (1)
There must be a porous reservoir—sandstone or porous lime-
stone—in which the oil or gas may accumulate, and this must
be covered with shale or other impervious deposit to prevent
the hydrocarbons from escaping to the surface and becoming
lost as fast as they are generated. But reservoir and cover
alone will not insure a supply. So long as the rocks lie flat or
have a uniform dip there will be no accumulations of any im-
portance. (2) The reservoir and cover must present a series
of folds beneath the arches of which the oil and gas are en-
trapped and accumulated under high pressure. Three condi-
tions, therefore, must exist conjointly—the source of supply
in some form of organic matter, the porous reservoir and im-
pervious cover, and the arched or folded condition of the beds.
It is the last of these conditions that is wanting in Iowa. Our
stratified rocks are not folded to anv noteworthy extent. The
compression and crushing which gave rise to the Appalachian
mountains produced folds as far west as Indiana, and then the
effects fade out. Jowa is too far away from other centers of

370 The American Geologist. June, TOGKs

crustal disturbance, such as the Ozark region of Missouri or
the great mountain axes of the west; and so the rocks are witli-
out the folds which are so essential to the accumulation of the
fluent hydrocarbons. Besides the Trenton limestone there are
petroleum-bearing rocks in other formations in Iowa, notably
in the Carboniferous; but so far as discovery has gone, some
of the conditions on which accumulation in commercial quan-
tities depends, are always absent. Usable quantities of gas have
been found at a few places in Iowa in the drift. This gas has
its origin in the buried forests; beds of sand and gravel consti-
tute the reservoir; and overlying bowlder clay is the impervi-
ous layer. Near Herndon and Letts are wells of this kind.
The volume of gas is small; its source is near the surface;
nothing would be gained, but much might be lost, by deeper
borings. If either oil or gas is ever found in Jowa in usable
quantities, outside the drift, it will be found either in or above
the Trenton. There is no possibility of its occurring below that
formation. Now, remember that deep wells which have pene-
trated the whole thickness of the Trenton and gone hundreds
of feet below it, are scattered all over ‘Iowa. Every one of
these wells, no matter for what purpose it was made, is, in ef-
fect, a test hole for gas and oil; and every one of them answers
the question of the occurernce of these products in a way that
might be inferred from what is known of the geological struc-
ture—namely, in the negative. The state has been very thor-
oughly explored beyond the deepest point at which there is the
slightest hope of success, and a thousand other test holes would
not make the situation any clearer or the results more decisive.
There is always the very remote possibility that there may be a
.small arch somewhere which has not been pierced by the drill,
but the chances of its existence are so few, that if the object is
simply to test for gas or oil, it would be an unjustifiable waste
of money to search for it even if holes could be bored every-
where down into the Trenton limestone at the rate of one doi-
lar apiece. The geological structure of the state, in its broader
features, is now thoroughly known. The records of the many
deep wells, so fully and accurately described by Norton in Voi-
ume VI of the Iowa Reports, reveal that structure in scores of
places down to the Algonkian; and from the base of the Al-
gonkian to the earth’s center, there is nothing but barren, igne-

Gold and Other Minerals in Iowa.—Calvin. 371

ous rocks in which drills might be worked eternally without the
remotest prospect of finding even so much as a trace of gas or
oil.

There is another fallacy which should be disposed of, if it
is ever possible to dispose of any of the popular and deep-root-
ed fallacies concerning what is hidden from ordinary observa-

tion beneath the surface of the ground. However it has arisen,

there is a wide-spread belief that experts in some way are able
to judge of the presence or absence of valuable products by an
examination of the topography and general characteristics of
the surface of any given region. Unscrupulous persons, tak-
ing advantage of this belief, have robbed some Iowa communi-
ties unmercifully. Such persons usually own an elaborate out-
fit for drilling, and naturally they want to keep themselves and
their machines employed. The community to be victimized is
easily selected. With specious claims of expert knowledge and
elib assurance that this hill and that ravine and the relations
of the level plain all bear unmistakable evidence of underlying
wealth of the very kind that the community for the moment
most desires, the requisite amount of money is quickly coaxed
from the pockets of the public spirited subscribers, the hole is
bored, the driller gets his pay, and the community is left to re-
pent its folly at its leisure. Not infrequently it is the public
spirited men of the community who take the initiative, and,
without knowledge of their own and asking no advice, but firm
in the belief that the earth will yield anything desired if we
only go deep enough, they proceed with the drilling of test
holes on a scale involving the expenditure of thousands of dol-
lars. The end is inevitable. It is that which invariably fol-
lows every ill-advised enterprise in which ascertained facts are
ignored. The disappointment may be all the keener when the
promoters realize that the facts bearing on the case were easily
ascertainable.

The highest living authority on the distribution of oil and
gas, the man who has done more than any one else for the suc-
cessful and profitable development of all the interests related to
these two products, declares that the most valuable service
which science has been able to render in this connection has
been the determination of the fields wherein exploration is
hopeless. Iowans will do well to remember that, even in a

372 The American Geologist. Jase, aaa

state as munificently endowed as theirs, there are some things
and some favoring conditions which Nature has failed to pro-
vide, there are some drafts on Nature’s apparently limitless
bounty which must go unhonored, there are some enterprises
looking to the development of natural resources which in the
very condition and structure of things are absolutely hopeless.
Let them rather reserve all of their capital and energies for the
development of the splendid resources which do exist and not
waste any in the useless search for geological products which
all enlightened experience shows could not, by any known pos-
sibility, be developed in the state.

EDITORIAL COMMENT.

MuvseuM CATALOGUES.—Two catalogues of museums lie
on our table, the first by Prof. Renevier, and the second from —
the Smithsonian Institution,which illustrate among other things
the difference in the support to Science which is afforded in
Switzerland and the U. S. respectively. The first is entitled
“Notice sur l’origine et Tinstallation du Musee geologique de
Lausanne. (Lausanne, 1895.) Par Prof. E. Renevier.

In spite of its title but little more than half a page is de-
voted to the origin and installation of the collections. The re-
maining ten pages are dedicated to a description of the col-
lections and their classification. The collection is not a large
one, but some points are of interest.

Room I. The first collection is of general stratigraphy,
three glass cases exposing the principal classic fossils from the
earliest to the Cretacic.

The second is the petrogenic collection of 1,500 specimens
intended to teach the mode of formation of the rocks which
compose the terrestrial crust on a system of Prof. Renevier’s
as follows:

a) Deutoeogenic rocks of sedimentary origin by
’ mechanical means.

b) Organogenic rocks of sedimentary origin
through organic processes.

c) Hydatogenic rocks, of chemical origin by means
ot water.

Editorial Comment. 373

d) Pyrogenic rocks of chemical origin by means of
heat.

e) Crystogenic or crystalline rocks of doubtful
origin on account of their crystallization.

The subdivisions of these groups are, as far as possible,
equally based upon their mode of formation.

The third division is of the Cretacic fossils of the country.

The fourth is the Geotechnical collection, including orna-
mental marble, slate, etc.

The fifth is the Morphological collection (Erosion, actual
consolidation, organic perforation, etc.

The sixth is of geological maps, profiles, photographs etc.

Room II. The hall of regional geology (collections of the
western Alps and of the Southern Jura), etc.

III. Paleontology (Fossil mammals; Birds, Reptiles and
Fishes, etc.

IV. Mineralogical hall, etc.

This is an unusal arrangement, especially that of the first
division with its miscellaneous department at the end.

Far different is Curator Merrill’s “Guide to the study of the
collections in the Section of applied Geology.”

The non-metallic Minerals by George P. Merrill. (From
the report of the Smithsonian Institution for 1899, pp. 155 to
483 with thirty plates. “‘Washington. Government printing
office, 1901.”

The 328 pages of this useful catalogue interspersed with
plates and cuts follow the general classification of Dana in
general in the groups which are I. The Elements. II. Sul-
phides and arsenides. III. Halides. IV. Oxides. V. Car-
bonates. IV. Silicates. VII. Niobates and Tantalates. VIII.
Phosphates. IX. Nitrates. X. Borates. XI. Uranates. XII.
Sulphates. XIII. Hydro-carbon compounds. XIV. Miscella-
neous.

Under these latter it is to be regretted that the Mineral
Waters are stowed, as if in the way. They deserve a sepa-
rate chapter like the rest. The lack of a proper bibliography
of mineral waters of the United States was felt when Daubrée
was writing his great work on Les Eaux Souterraines; and
sought in vain for systematic information on the subject in this
country. Little more than the advertising sheets of rival min-

374 The American Geologist. Jane iee

eral springs with analyses by known and unknown persons—
principally physicians or druggists of the immediate neigh-
borhood, could be obtained.

The catalogue of the XIII sections is admirably full and
contains besides the American and principal foreign localities,
ot each particular product, a very useful bibliography.

Pai

CONTRIBUTIONS TO THE LITERATURE OF VOLCANOES.—An
interesting review of the great work of Stubel on the volcanoes
of Ecuador has appeared in the Bulletin of the Société Belge de
Géologie de Paléontologie et d’ Hydrologie, by Prof. W. Prinz,
of the free University of Brussels. The title is “Les volean-
oes de l’Ecuador par Alph Stttbel. Resumé des theories
d’interet général contenues dans cet ouvrage. par W. Prinz,
Professeur a l'Université libre de Bruxelles.”

He states that Stttbel was of those who seek the remotest
regions for new facts with which to enrich science, and that he
had remained for nearly ten years in the high region of Colum-
bia and Ecuador to study the volcanoes. His results were six
thousand specimens of rocks and the aquarelles, sketches, and
even oil paintings of M. Troya, an artist who accompanied
him, all of which are in the ethnographic museum at Leipzig.
The volume which is reviewed is intended as a descriptive cat-
alogue of these objects. There are 14 cuts in the text and a
map on a large scale 1:250,000 by M. Th. Wolf. The meas-
urements on which the map is based are discussed by M. B.
Peter of the Observatory of Leipzig.

M. Stttbel after much hesitation in grouping the separate
cones finally concludes that there are but 41 volcanoes in Ecua-
dor, grouped in two chains which enclose the high plateau to
the east and to the west. The object of the study is to seek
the connection which still exists between the eruptive manifes-
tations and the part of the globe yet in a state of fusion, or in
other words do the modern volcanic phenomena depend on the
development of the earth?

The tendency of his reasoning is to the negative, and in
support he cites the enormous thickness of the crust (even
where supposed to be least so.) What disproportion between
the flow of lava and the supposed source! Earthquakes too
are from causes not situated very deep.

Editorial Comment. 375,

The distribution of the volcanoes in Ecuador, Columbia,
Bolivia, Chili, and Mexico, Central America, and the Aleutian
group is very remarkable, for it is evident that a great nucleal
centre would not discharge the excess of its igneous fluid by
narrow channels, but by great orifices in the regions of flow,
which would be kept permanently open during the eruptive
period.

He leaves the same dilemma which his object was to solve.
Either the earth is surrounded by a thin crust although its in-
terior is in a state of fusion, which is in contradiction with cer-
tain geological and astronomical facts, although offering an
easy explanation of volcanic action; or the earth is solid to a
great depth and contains only a relatively unimportant kernel
of igneous materials, which conforms to the astronomical and
geological facts but leaves the eruptive phenomena unaccount-
ed for. i a

GILBERT'S SUMMARY HISTORY OF NIAGARA FALLS.

Numerous partial descriptions and discussions of Niagara
river and Niagara falls have been published in late years, ow-
ing to the rapid growth of the Pleistocene geology of the re-
gion of the great lakes. Some views have not been in accord
with others, and some geologists have amended their own
views. The result is that those who have not closely noted the
development of this history find some difficulty in forming a
consistent idea of the actual result arrived at by these re-
searches. Below is the summary of this result as given by Mr.
G. K. Gilbert in connection with the new map of Niagara river
and the Pan-American Exposition, dated May, 1got.

N. H. W.

“The beginning of the river is intimately associated with
the Glacial or Pleistocene period. Before that time lake Erie
and lake Ontario did not exist and there was a very different
system of rivers in the region. In the early part of the period
glaciers were formed on the highlands of Canada, and gradu-
ally grew and spread until they covered all the region of the
great lakes. They eroded the land in places and deposited the
eroded material elsewhere in the form of drift. Then they
melted back so as to uncover the lake region, making an inter-
glacial epoch, and afterwards they again grew large. These

376 The American Geologist. June, 1901.

oscillations were several times repeated, so that the Pleistocene
period was composed of several glacial epochs separated by in-
terglacial epochs. Each interglacial epoch had its own system
of lakes and rivers, and in one of these epochs a great river
traversed the Niagara district, crossing the escarpment a few
miles west of the mouth of the Niagara gorge. Like the Ni-
agara, it made a gorge, and this gorge was eaten back from
the neighborhood of the village of St. Davids to the position.
of the present Whirlpool. The readvance of the glacier not
only abolished this river but filled with drift the gorge it had
made, so that one may now cross it on what is known as the
Old Portage road without suspecting the existence of a buried
valley.

“When the ice for the last time melted from the land, it
left a hollow which we know as the basin of lake Erie, and
another hollow which contains lake Ontario, and it left the face
of the land in such shape that the overflow from one lake to
the other could not follow the valley of an earlier stream but
sought out a new course. Thus the Niagara river was born;
and its cataract has been engaged ever since in the making of
the gorge.

“Tust before the establishment of lake Ontario there was a
greater lake in the same basin, with an outlet to the Mohawk
and Hudson rivers instead of the St. Lawrence. The aban-
doned shore of this greater lake, called by geologists the Iro-
quois beach, lies close to the escarpment and can be traced out
by means of its bluffs and ridges. Its line is followed for
many miles in New York by a road called the Ridge road, ‘and
this road crosses the map. At Dickersonville it runs on a typ-
ical beach ridge of gravel and sand. Near Model City it is
on top of the ancient shore bluff, and in Lewiston it is on a
gravel ridge which was built as a spit in the old lake.

“After the disappearance of the ice the land it had covered
was gradually uplifted, the rate of rising being different in dif-
ferent parts. As a result of this warping of the earth the out-
lets of certain lakes were changed, and these changes had an
- important influence on Niagara river. There were two epochs
during which most of the water of the great lakes region
flowed to the ocean by other routes, leaving to the Niagara only
the water from the lake Erie basin. During these epochs the
river was much smaller than it now is, probably carrying only

Editorial Comment. Jame

one-eighth of the present amount of water, and the cataract
was then a less powerful agent of erosion. The deeper parts
of the gorge, which now contain pools, were excavated by the
cataract when the volume of the river was large. The shallow
parts, which now contain rapids, were excavated when the vol-
ume was small.

“The determination of the age of the river, or the time
which has been consumed in the making of the gorge, is a
problem of great interest, to which much attention has been
given. As the length of the gorge is known and as the rate
at which the cataract now lengthens the gorge is known, it
would seem a simple matter to compute the time. Taking the
gorge length as a dividend and the annual change in length as
a divisor, we obtain 7,000 as a quotient, and this has been as-
sumed by some to represent the number of years occupied by
the river in the work. But this computation fails to take ac-
count of a number of important considerations. The thickness
of the limestone is not the same in all parts of the gorge; the
hight of the cataract was not the same through the whole
period ; and, as just pointed out, the volume of the river was
sometimes much less. The last-mentioned qualification is the
most important of all, for the diminished river would erode
much less rapidly than the full river. If we knew precisely
what difference the change of volume would make, a fairly sat-
isfactory result might be obtained, but this we do not know.
The smaller of the two divisions of the cataract, known as the
American fall, now contains nearly as much water as did the
whole river during times of diminished drainage basin. But
the crest line of the American fall has not changed its form
appreciably since the year 1827, when the first accurate draw-
ings of it were made. Its recession must be many times slower
than that of the Horseshoe fall. This fact indicates that the
rate of erosion of the narrowest parts of the gorge was exceed-
ingly slow and the time consumed exceedingly Iong. Its esti-
mation is little better than a guess. One may say with sonic
confidence that 7,000 years is altogether too small.an estimate
of, the age of the river, but whether the real age is expressible
in tens of thousands or in hundreds of thousands of vears is
at present a matter of doubt.” at

Tue TerM Hupson River.—Dr. Rudolf Ruedemann has
reviewed the rather quixotic record of this term in geological

378 The American Geologist. Jqne. Say

literature in a recent publication by the New York State Mus-
eum.* He also adds many new facts relating to the geograph-
ic and stratigraphic distribution of theyfossils. He concludes
that the Norman’s Kill series of shales represents the most im-
portant part of the Hudson River series, but that its fauna is
only one of four faunas which are embraced in the Hudson
River rocks, and the lowest of the four. He also finds that
the Norman’s kill shales are in the Trenton, lying immediately
on the lower Trenton limestone. His summary conclusion is as
follows: N. H. W.

“This paper purports to demonstrate the presence of four
zones of shales-in the ‘Hudson River shales’ of the Hudson
valley region about Albany. These zones, which extend from
N. N. Eto S. S. W., consist, going from west to east, of shales
containing the Lorraine, Utica, Middle Trenton and Norman’s
kill graptolite faunas. The shales last named include lower
Trenton conglomerate and rest on lower Trenton limestone.
This succession of zones places the Norman’s kill graptolite
beds, which form the mass of the Hudson River shales in the
Hudson river valley, between the middle and lower Trenton,
and determines, together with other facts, the Lower Trenton
age of these shales.

“The beds lie conformably inverted, on account of their be-
ing the remnant of the underturned wing of an overturned fold
of the Appalachian type. This fold has turned into an over-
thrust fault which brought the Cambric beds as the next suc-
ceeding terrane above the Norman’s kill shales.

“On account of the fact that the mass of the beds hitherto
called Hudson River shales and correlated with the Lorraine
beds of central New York, is composed of terranes ranging
from the Lorraine to the lower Trenton, and on account of a
lack of a fully representative fauna and of a complete section
of the Lorraine portion of these terranes, it is proposed to drop
the term Hudson River shales for the uppermost part of the
Lower Siluric, and the term Hudson River group for the Utica
and Lorraine beds, and to employ the term Norman’s Kill
shales for the clastic facies of a part of the lower Trenton
which is characterized by the graptolite fauna of the Norman’s
kill.”

* The Hudson River beds near Albany and their Taxonomic equivalents,
Bull. No, 42, vol. viii, April, 1901.

Review of Recent Geological Literature. 379

REVIEW OF RECENT GEOLOGICAL
LITERATURE. -

Phylogeny of the Rhinoceroses of Europe. By Henry Farrcuitp Os-
. BORN. (Bull. Am. Mus. Nat. Hist., vol. x1tt., article x1x., pp. 229-

267, 1900.) é
Some New and Little Known Fossil Vertebrates. By J. B. Harcuer.

(Annals, Carnegie Museum, vol. 1, 1901, pl. 1-4.)

The Rhinocerotide have hitheto baffled the taxonomist, and their
origin, development and migration are still problematic. The phylogeny
proposed by Mr. Osborn divides the rhinoceroses into six phyla, hav-
ing no known relation to each other. The supposed stem forms are
traced back to the early Cenozoic, thereby suggesting that the rhinocer-
oses, like numerous other mammalian phyla, come under the law of
early divergence.

Mr. Osborn bases his classification upon the proportions of the
skull and correlated proportions of the body and upon the location of
the horn cores. He finds these to be the main divergent characters,
setting aside several homoplastic characters heretofore employed in
classification.

Besides suggesting a hypothesis of descent, Mr. Osborn offers some
interesting systematic and comparative descriptions, based upon the
study of the collections in various European museums.

Mr. Hatcher’s paper is based upon material collected by the pale-
ontological expedition of 1900, for which Mr. Andrew Carnegie sup-
plied the funds. He describes Trigonias osborni, a new genus of rhi-
noceros, from the base of the White River Oligocene. The manus
differs from all other known American rhinoceroses in being function-
ally tetradactyl; it has an unreduced number of superior teeth; and
simple structure of the superior premolars. It is therefore of a gen-
eralized type, and is the most primitive member of the Rhinocerotedz
at present known. °

The comparison with the unreduced teeth of Trigonias will make
‘ possible the establishment of the homology of the teeth of the modern
rhinoceroses. Trigonias probably represents the ancestral form of one
of Mr. Osborn’s six groups, the Acerathertinae. I. H. 0.

380 The American Geologist. Jute Sees

MONTHLY AUTHOR’S CATALOGUE
OF AMERICAN GEOLOGICAL LITERATURE
ARRANGED ALPHABETICALLY,

Ami, H. M.
Brief biographical sketch of Elkanah Billings. (Am. Geol., vol.
27, pp. 265-281. May, 1901.)

Ami, H. M.

The late George Mercer Dawson. (Ott. Nat., vol. 15, pp. 43-52.
May, 1901.)
Barbour. be

Sand crystals and their relation to certain concretionary forms.
(Bull Geol. Soc. Am., vol. 12, pp. 165-172, pls. 13-16. Apr., 1901.)

Beede, J. W.

A reconnaissance of the Blue valley Permian. (Kans. Univ. Quart.,
vol. 9, pp. 191-202, pl. 43.
Brooks, A. H.

A new occurrence of cassiterite in Alaska. (Science, N. S., vol.
Sip. 503. Apiete aLoOr)
Brooks, A. H.

A reconnaissance from Pyramid harbor to Eagle City, Alaska, in-
cluding a description of the copper deposits of the upper White and
Tanana rivers. (21st Ann. Rep. U. S. Geol. Sur., Part 2, pp. 331-391.
map, pls, xl-xlix. 1goo.)

Chalmers, R.

The sources and distribution of the gold-bearing alluvions of Que-
bec. (Ott. Nat., vol. 15, p. 33. May, 1901.)

Coleman, A. P.

Marine and Freshwater beaches of Ontario. (Bull. Geol. Soc. Am.,
vol. 12, pp. 129-146. Mar., 1901.)

Crosby, W. O.

Are the amygdaloidal melaphyrs of the Boston basin intrusive or
contemporaneous? (Am. Geol., vol. 27, pp. 232-327. May, Igor.)

Cumings, E. R.

The use of Bedford as a formational name. (Jour. Geol., vol. 9,
Pp. 232-233. Apr.-May, 1901.)
Dawson, G. M.

Summary Report on the operation of the Geological Survey for the
year 1900. (Geol. Sury. Canada. Sessional paper, No. 26, 64 Victoria,
IQOT. )

Author's Catalogue. 381

Ells, R. W. °

The Physical Features and Geology of the Paleozoic basin between
the Lower Ottawa and the St. Lawrence rivers. (Trans. Roy. Soc.
Can., vol. 6, sec. ser., section iv, pp. 99-120. 1900. )

Gallaher, Leo.

Biennial report of the State Geologist (Missouri). Jefferson City.
Pp. 55. Igor.

’. Gannett, Henry.

The general geography of Alaska. (Nat. Geog. Mag., vol. 12, pp.
180-196. May, 1901.) .
Grabau, A. W.

Lake Bouvé, an extinct glacial lake in the Boston basin. (Occ. Pap.
Bos. Soc. Nat. Hist., vol. iv, part 3, pp. 564-600. July, 1900.)

Hall, C. W.

Sources of the constituents of Minnesota soils. (Bull. Minn. Acad.
Sci., vol. 3, pp. 388-406. 1901.)

Hershey, O. H.

The geology of the central portion of the Isthmus of Panama. (Bull.
Dept. Geol., Univ. Cal., vol. 2, pp. 231-267. Mar., 1901.)

Hilgard, E. W.

A historical outline of the geological and agricultural survey of
Mississippi (Am. Geol., vol. 27, pp. 284-310. May, 1901.)

Hollick, Arthur.

A reconnaissance of the Elizabeth islands. (Ann. N. Y. Acad.
Sci., vol. 13, pp. 387-401, pls. vili-xv. 1901.)

Keyes, C. R.

Derivation of the terrestrial spheroid from the rhombic dodecahe-
dron. (Jour. Geol., vol. 9, pp. 244-249. Apr.-May, 1go1.
Keyes, C. R. .

A depositional measure of unconformity. (Bull. Geol. Soc. Am.,
vol. 12, pp. 173-196, pl. 19. Apr., Igot.
Kummel, H. B. (and Stuart Weller)

Paleozoic limestones of the Kittatinny valley, New Jersey. (Bull.
Geol. Soc. Am., vol. 12, pp. 147-164. Apr., I90I.)

Lambe, L. M.

A revision of the Genera and species of Canadian paleozoic corals.
The Madreporaria aporosa and the Madreporaria rugosa. (Cont. Can.
Pal., vol. 6, Part 2, pp. 97-197. Geol. Sur. Can., pl. vi-xviii. 1901.)

McCaslin, D. S.
The Geology of the Artesian basin in South Dakota. (Bull. Minn.
Acad. Sci., vol. 3, pp. 380-388. 1901.)

Merriam, J. C.
A contribution to the Geology of the John Day basin. (Bull. Dept.
Geol., Univ. Cal., vol. 2, pp. 269-314. April, 1901.)

382 The American Geologist. June, 1901.

Nichols, Henry W.

Nitrates in cave earths. (Jour. Geol., vol. 9, pp. 236-243. Apr.-May,
IQOT. )

Owen, Luella Agnes.

The bluffs of the Missouri river. (Verhandl d. vii Intern. Geog.
Kong. in Berlin. 1899. pp. 686-690. )

Pearson, H. W.

Oscillations in the sea level. IJ. (Geol. Mag., vol. 8, pp. 223-231.
May, 1901.)

Peck, F. B.
Preliminary notes on the occurrence of serpentine and tale at East-
ton, Pa. (Ann. N. Y. Acad. Sci., vol. 13, pp. 419-427, pl. xvi. I90T:) *

Prosser, C. S.

The classification of the Waverly series of central Ohio. (Jour.
Geol., vol. 9, pp. 205-231. Apr.-May, 1go1.)
Reid, H. F.

The variations of Glaciers. vi. (Jour. Geol., vol. 9, pp. 250-254.
Apr.-May, 1901.)
Sardeson, F. W.

Fossils in the St. Peter sandstone. (Bull. Minn. Acad. Sci., vol. 3,
p- 318. 1901.)
Sardeson, F. W.

The Lower Silurian formations of Wisconsin and Minnesota com-
pared. (Bull. Minn. Acad. Sci., vol. 3, pp. 319-326. Igot.) .

Sardeson, F. W.

The range and distribution of the Lower Silurian fauna of Minne-
sota, with descriptions of some new species. (Bull. Minn. Acad. Sci.,
vol. 3, pp. 326-343. I90T.)

Sardeson, F. W.

Paleozoic fossils in the Glacial drift of Minnesota. (Bull. Minn.
Acad: Scie voles ps3i7., 160ie)

Siebenthal, C. E.

On the use of the term Bedford limestone. (Jour. Geol., vol. 9, pp.
234-235. Apr.-May. IgoI.)

Smith, Herbert W.
Preliminary notes on the conglomerate and amygdaloids of the

Snake river valley. Abstract. (Bull. Minn. Acad. Sci., vol. 3, p. 312.
I9OI. )

Smith, James Perrin (and Stuart Weller).

Prodromites, a new Ammonite genus from the Lower Carbonifer-
ous. (Jour. Geol., vol. 9, pp. 255-266. Apr.-May. tgo1. pls. vi-viii.)

Stevenson, John J.

The section at Schoharie, N. Y. (Ann. N. Y. Acad. Sci., vol. 13,
pp. 361-380. cor.)

Correspondence. 383

Upham, Warren.

Artesian wells in North and South Dakota. (Bull. Minn. Acad.
Sci., vol. 3, pp. 370-379. ISOI.)
Warren, C. H.

Mineralogical notes. (Am. Jour. Sci. vol. 11, pp. 369-373. May,
19OlI. )
Weeks, F. B.

An occurrence of Tungsten ore in eastern Nevada. (21st Ann. Rep.,
U.S. Geol Sur., part vi, p. 319. 1901.)

Weller, Stuart (H. B. Kummel and)

Paleozoic limestones of the Kittatinny valley, New Jersey. (Bull.
Geol. Soc. Am., vol. 12, pp. 147-162. Apr., 1901.)

Whiteaves, J. F.

Note on a supposed new species of Lytoceras, from the Cretaceous
rocks of Denman island, in the strait of Georgia. (Ottawa Naturalist,
Vol. 15, pp. 31-32. Mar., 1¢or.)

Winchell, N. H.

The Geology of Minnesota, final report, vol. vi. Geological atlas,
with synoptical descriptions, 89 plates. St. Paul, rgor.

Woodworth, J. A.

Original micaceous crossbanding of strata in current action. (Am.
Geol., vol. 27, pp. 281-284. May, r1got.)

Wortman, J. L.

Studies of Eocene mammialia in the Marsh collection, Peabody mus-
eum. (Am. Jour. Sci., vol. 11, pp. 333-348. May, 19ot.)

CORRESPONDENCE.

ARE THE St. JoHN PLANT Beps Carponirerous? The writer has
been urged to take notice of the opinion of Dr. David White, of the
United States Geological Survey, expressed as to the age of the St.
John plant beds, or “fern ledges,” as they were designated by the late
professor C. F. Hartt.

As long as Mr. White’s statement of the age of these beds was ex-
pressed merely as an opinion based on the composition of the flora
which these beds contain (which flora he regarded as that of the Potts-
ville conglomerate of Pennsylvania, or in English parlance the Mil!
stone grit*), it did not seem to call urgently for reply. But since he
has lately written a communication to the Natural History Society of

* U.S. Geol. Surv. 20th Ann. Rep. Part ii, General Geology, &c., page 917.

384 The American Geologist. June, 1901.

Montreal, wherein he has stated that the “erroneous reference of this
fauna to the Devonian was forced upon Sir William [Dawson] by the
findings of the stratigraphers,’} it becomes necessary for the writer to
’ show something of the history of these “findings,” since to him and to
professor L. W. Bailey is chiefly due the assignment of the age re-
quired by the stratigraphy. |

With this question is now involved the age of certain anneneeane
terranes in Nova Scotia, surveyed and mapped by Messrs. Hugh
Fletcher and R. W. Ells, of the Canadian Geological Survey; but in
this communication the writer proposes to confine himself to the New
Brunswick areas, and to mention the stratigraphical points bearing on
the age of the plant bed as briefly as possible.

The ‘Millstone grit” is well developed in New Brunswick, with
floras at various points; and visibly at almost all points where its bor-
ders are exposed, is underlain by red shales and conglomerates with
some Lower Carboniferous limestones. The gray rocks (Millstone
grit) have been traced and surveyed by Drs. L. W. Bailey and R, W.
Ells from a point about 30 miles north of St. John, eastward to the
Joggins section in Nova Scotia.

The underlying red shales and conglomerate above mentioned, or to
use the Pennsylvania nomenclature, the Maunch Chunk shale, comes
within three miles of St. John on the north and an outher is found
one mile to the southeast of the city. These rocks are inclined at low
angles from the pre-Carboniferous complex on which they rest, and the
outlier reposes upon the contact of the Mispec and Little River terranes
unconformably. ;

In the valley of the Kennebecasis and the Pettecodiac rivers (which
are continuous) extending northeast from St. John about eighty miles
there appear at intervals beneath the equivalent of the Maunch Chunk
red shales, bodies of gray and dark gray bituminous shale (near St,
John mostly gray standstones) and underlying conglomerates, that were
much eroded before the deposition of the red shales, etc. These gray
shales contain at various points frequent remains of Ansimites acadica
and Lepidodendren corrugatum, and are the equivalent of the Pocono.

Down to the base of this series the sandstones are “free stones,”
that is they have not been filled with a secondary growth of silica be-
tween the grains; the plants in the shales retain their bitumen; the

limestones are not metamorphosed and the igneous effusives contain °

zeolites. Below this the sandstones are strongly cemented with silica
and some calcite, the shales are converted into slates, the limestones
are more crystalline, and the beds are usually tilted at high angles.

The division between the rocks in these two conditions is the line of
a great unconformity with discordance of dip, and usually strike as well,
between the underlying and overlying measures.

The first terrane below the unconfomity is the Mispec—Conglomer-
ate and red slate. As this terrane contains rolled fragments of Silur-
_ian corals the whole series below it to the horizon of these corals must
have been denuded before or during its formation.

7_Can. Rec. Sci. Vol. viii, p. 277.

Correspondence. 385

The next terrane is the Little River group which contains the plant
beds of the “fern ledges.” To the stratigrapher it appears absurd to
speak of these being equivalent to the Pottsville conglomerate (i. ¢., the
Millstone grit) in age. :

Lest it might be thought that the reference of the plant beds of
St. John to this*low horizon, rests only on the writers’ early determina-
tions, supported later by Drs. L. W. Bailey and R. W. Ells, he may
say that Sir William Dawson went over these sections before he wrote
his classic papers and reports, wherein he referred them to the Middle
Devonian. Dr. T. Sterry Hunt also spent a good part of one season
in examining the southern coast region of New Brunswick with Dr. L.
W. Bailey and the writer; and Dr. Selwyn when Director of the Can-
adian Geological Survey, went over the same ground; as he gave the
imprimature of the survey report to the view above expressed, it is to be
presumed that he was satisfied with the evidence in its favor.

The fact of the matter is that Mr. White has read the biology of the
plant bed flora from the wrong end. A few of the ancient types of
this flora (Archzopteris) were known when Rogers made the first
geological survey of Pennsylvania. And since Dawson studied the
flora other types have been gradually gathered from the lower horizons
of the Carboniferous: Megalopteris for instance was found in several
species in Ohio by professor Andrews from the lower coal measures,
and later Lesquereux described others, gathered chiefly in the south
and the Mississippi states from the equivalent of the Maunch Chunk red
shale. It would appear that a number of the species of this flora sur-
vived in Pennsylvania until the time of the Pottsville conglomerate.

The reference of these plant beds to the Millstone grit reminds one
of the persistency with which Lesquereux some thirty or forty years
ago clung to the view that the Lignite beds of the west were of
Tertiary age, whereas it has been amply shown by the marine fossils
that they are Cretaceous.

Many genera of plants have a wide vertical range; witness the
recent genera, Amentacee &c., in the Cretaceous, some species of
which are very difficult to distinguish from modern forms; is the Cre-
taceous recent because it contains these? Some species of marine
forms (Brachiopods and Trilobites even) range through a whole geo-
logical system, why may not some plants?

To recapitulate, the following changes occurred between the depo-
sition of the St. John plant beds and the formation of the Millstone
grit.

Erosion of strata to the Niagara horizon with deposition of the
Mispec terrane.

Crushing and folding of the unconsolidated terranes from (and in-
cluding) the Mispec downward. Extrusion of granite.

Deposition of the Albert shale and conglomerate=Pocono.

Erosion to the Laurentian or Fundamental complex, with deposition
of red slate and conglomerate=MWaunch Chunk.

386 The American Geologist. Juss, 3e4

Slight deformation of the crust with deposition of the Millstone
erit=Pottsville Conglomerate. G. F. MatrHew.

St. John, N. B., April, 1901.

THe Structure oF DiAMonp HeEAp; OAHU.—Two summers ago |
made some observations on the structure of the beds at and about
Diamond Head, Oahu, Hawaiian Islands. A brief summary of them
was printed by Dr. C. H. Hitchcock in his account of the geology
of Oahu (Bull. Geol. Soc. of Am., 11 pp. 57-Go.) I am not aware that
there is anything in these observations to excite emotion, but it resulted
in some very emotional newspaper articles, followed in cooler vein by
contributions to other periodicals including a paper in the AMERICAN
GeoLocist for January last, pp. 1-5, by the Rey. Dr. S. E. Bishop, and
still others later. I am averse to controversy in matters which can be
settled by an appeal to facts, and especially to controversy over a
scientific matter with a person not trained in the specialty to which the
subject matter belongs: for reasons which are obvious. Moreover, Dr.
Bishop is known as an amateur observer who has done service to
science in various ways and a most worthy person, individually.

The reiteration of the opinions expressed by the reverend doctor has
been so prolonged that it has been suggested to me that further silence
on my part might be misunderstood among geologists, and, therefore,
I ask space in your journal for a few statements, as follows:

1. The hypothetical cone described at such length by Dr. Bishop.
does not, as a matter of fact, exist at Diamond Head.

2. The observations made by me and recorded in Dr. Hitchcock’s
paper above referred to, are sound; and can be verified by any person
with good eyes, reasonable powers of observation, and a moderate
familiarity with Tertiary stratigraphic geology.

_ 3. The inferences or hypotheses which I drew from those observa-
tions are subject to the criticism of experts in Tertiary geology and
will take their chances of acceptance in the usual manner.

4. The old beaches with their corals, sedentary bivalves like Chama,
Ostrea, etc., and other attached invertebrates, remaining as they grew
in life, extend at least two-thirds around the cone, where I traced them
(and I have little doubt, entirely around it), and under the tuff and
thin sheets of lava of which the lower part of the cone is composed.
Every little bluff at Pearl Harbor and sections cut in sewering the city
of Honolulu exhibit similar phenomena, which are probably common
to the entire periphery of the island where the sea has not eaten them
away. The inter-stratification is undeniable except in defiance of the
most obvious facts. But the elevation is greater toward Diamond
Head and less in the opposite direction, though the difference is not
very great. In the middle portions of the cone the beaches are replaced
‘by horizontal layers of compacted coral sand which can be seen half a
mile, and which leaches out in=the calcareous snowy crusts so conspic-
uous on the slopes. I did not visit the upper part of the cone, but it
presented no external appearances different from that lower down.

5. I do not intend to publish anything further on this subject, in
this connection.

Personal and Scientific News. 387

I may add that very similar phenomena can be observed on the
north shores of Unga and Popoff islands of the Shumagin group,
Alaska, where the age is probably Oligocene. Wm. H. DALtt.

Smithsonian Institution, May 1, 1901.

PERSONAL AND SCIENTIFIC NEWS.

J. W. Breve has been appointed instructor in geology at
Indiana State University, Bloomington, Ind.

Dr. J. B. WoopwortH has been appointed assistant pro-
fessor of geology at Harvard University, Cambridge.

Mr. WarrEN UpHam will attend the Dartmouth College
Commencement, June 23 to 26, the thirtieth anniversary of his
graduation.

THE CascapDE TUNNEL, by which the Great Northern rail-
road passes the Cascade mountains, is three miles long and is
cut wholly in granite.

Dr. T. C. Hopkins, professor of geology at Syracuse Uni-
versity, will work on the Geological Survey of Indiana during
the present summer. His work will be on the geological map
of the state.

ProF. R. WuHiIrTFriELD has returned from several weeks
stay in the ene where he secured for the American Mu-
seum of Natural History a number of remarkable specimens
of corals, to be added to the magnificent series which he has
obtained on previous visits to the. islands and presented to the
institution.

Tue Unirep Stares GEOLOGICAL Survey Has IssuED a
map of Niagara river and vicinity on a scale of 1 :62500, show-
ing the topography and the culture features, which will be of
great convenience to all who, visiting the Buffalo Pan-Ameri-
can Exposition, desire to make some examination of the geol-
ogy of the region.

THe Next MEETING OF THE AMERICAN ASSOCIATION FOR
THE ADVANCEMENT OF SCIENCE, and of the Geological Society
of America, will be held at Denver, Colo., Aug. 24 to Aug. 31.
C. D. Walcott is president of the Geological Society and C. R.
Van Hise is vice-president in charge of the section of geology
and geography of the Association.

Miss L. A. OweEN describes, in Verhandl. des VII. internat.
Geographen-Kongresses, Berlin, 1899, the discovery of a large
stone ax imbedded in the bluff on the west side of the river at
Atchison, Kansas, twenty miles south of St. Joseph, Mo. The
implement, whose discovery is attested by affidavit taken by an
eminent attorney, was found in comparatively undisturbed
loess, four feet below the surface.

388 The American Geologist. June, 1901.

Ernst HarEckeEL writes from Baden Baden, on April 14,
1901, pleasantly to a member of the GroLocisr staff:

Hicuty Honorep Frienp: I have just returned from an
eight months’ voyage to Java and Sumatra (of which you will
find an account in the Berlin “Deutscher Rundschau” ).

I return to Java on the 28th inst. and re-commence my lec-
tures on the 30th. * * * With best wishes.

Ernst HAECKEL.

THE Warp-CooLey CoLLecrion OF METEORITES, at Chica-
go, has representatives of 541 falls or finds, being the largest in
the world of number of kinds, the collection in the British
museum being next, according to their last catalogue. Of
these 201 are from North America, 23 from South America,
189 from Europe, 58 from Asia, 17 from Africa and 23 from
Australia. A new catalogue of:this collection has lately been
prepared by Prof. H. A. Ward.

AccorDING To Pror. H. McCattey, in Mines and Minerals,
the coke industry in Alabama has grown even faster than
coal mining. It was not known until 1876 that the Alabama
coals would make good coke, suitable for smelting, and now
Alabama ranks third of the states of the Union as a coke-pro-
ducing state, being surpassed only by Pennsylvania and West
Virginia. The coke output of the state for the calendar year
1899 was given by the State Mine Inspectors at 1,798,612 tons. -

AccorDING To O. D. WHEELER’S WONDERLAND FOR IQOI,
the first published description of the geysers, and other remark-
able features of the Yellowstone National Park, was written by
W. A. Ferris, published in the Western Literary Messenger, in
July, 1842, at Buffalo, N. Y. He visited the park May 19 and
20, 1834. He was a trapper, of more than ordinary education
and intelligence, originally a civil engineer, connected with the
American Fur Company of St: Louis. He removed to Texas,
and died in 1873, near Dallas.

UNDER THE UNITED STATES GEOLOGICAL SURVEY in con-
nection with professor Osborn’s monograph on the titano-
theres, which is the first of the new series of monographs on
fossil vertebrates to be taken up, Mr. N. H. Darton, of the Sur-
vey, accompanied by Mr. J. B. Hatcher of the Carnegie Muse-
um in Pittsburg, will make a thorough investigation of the
titanothere beds in South Dakota to establish as definitely as
possible the stratigraphical relations of the horizons in which
such remains have been found.

Pror. C. R. VAN Hise, vice president, section E, Geology
and Geography, of the American Association for the Advance-
ment of Science, has announced a plan and program of a pro-
posed excursion for geologists from Aug. 17 to Aug. 26, pre-
ceding the Denver meeting of the association, intended to
accommodate also the members of the Geological Society of
America. The itinerary of the trip, which will be-within the

Personal and Scientific News. 389

state of Colorado, has been arranged with the cooperation of
Messrs. S. F. Emmons and Whitman Cross.

EXPLORATIONS IN ALASKA. It is reported that the United
States Geological Survey will send three expeditions to Alaska
this summer. The first, under J. W. Peters, will start from
Bergman, nearly 1,000 miles northwest of Sitka, and proceed
to the Arctic ocean. The party hopes to advance eastward as
far as the British boundary and will then turn westward again
and proceed toward point Barrow. The second party, led by
W. C. Mendenhall, will work in the vicinity of Kotzebue sound.
The third party, led by M. Gerdine, will continue explorations
in the region of Copper river.

Tue DEPARTMENT OF VERTEBRATE PALAEONTOLOGY of the
American Museum of Natural History will have three parties
in the field this season under the general direction of professor
H. F. Osborn. One will continue the work in the Pleiocene
beds of the Mt. Blanco region in Texas, where so many and
such fine remains of mastodons, horses and camels have been
found by the museum parties in recent years. The second
party will continue the excavation of the celebrated Bone Cabin
quarry in the Como district of Wyoming, while the third party
will prosecute the collection of dinosaurian remains in the
Black Hills region of South Dakota and Wyoming.

Lenicu University, at South Bethlehem, Pa., publishes a
list of the titles of theses to be presented by candidates for
degrees, June, 1901. This list gives sixty-one titles. They
are almost wholly scientific. The exceptions are two, one de-
voted to the modern meaning of socialism and the other to
Chaucer’s “Prologue.’’ Nine are in the course of mining erigi-
neering and the remainder, which is the larger half, are in
some line of engineering or in chemistry. Not one is devoted
to any phase of geology, nor to mineralogy nor to any ques-
tion of petrography. It seems anomalous that in a mining
state like Pennsylvania, whose geology has furnished many of
the important elements of the science in America, a univ ersity
of such scope and standing could graduate a scientific class of
sixty-one without evincing any sign of geology in the final
theses. °

GEOLOGICAL arene oF WASHINGTON. At the meeting of
this society on April 24, Mr. G. P. Merrill exhibited specimens
of the so-called Moldavites from Bohemia and Moravia and
gave a brief resumé of the views of various writers as to their
supposed meteoric nature. He also exhibited weathered peb-
bles of obsidian from several localities in the arid west which
showed corroded surfaces suggestively similar, and which he
regarded as produced by natural temperature variations and
the corrosive action of the atmosphere.

At the same meeting was exhibited a preliminary sketch for

390 The American Geologist. Jane, aaa

a geological section entirely across the United States, as com-
piled by Dr. A. C. Peale, for exhibition in the geological de-
partment of the National Museum. The horizontal scale was
‘two miles to the inch and‘the vertical scale 4000 feet to the
inch; the entire length of the section, so far as completed, be-
ing upwards of seventy-five feet out of a final approximation
of one hundred and twenty (120) feet. As the section is an
actual compilation from the various surveys, some very inter-
esting and striking results were brought out.

Du RING THE SPRING REC ESS, a party of nine students from
Harvard University accompanied Prof. W. M. Davis ona geo-
logical and geographical trip into Pennsylvania. On the train
from New York to Scranton via Lackawana road, a running
cross-section was made of the Triassic lowland and the trap
ridges, the highland hills and valleys, and the great Appalach-
ian valley, geological maps in hand. A day was spent on the
Susquehanna above Wilkesbarre, to see the meandering valley
in the Alleghany plateau; and evidence of at least two cycles
of erosion was found. Descending the river, a side trip was
made to the coal regions, where the scenes of industrial desola-
tion in the anthracite basins was in marked contrast with the
thrifty agricultural landscape prevailing outside the Pottsville
and Pocono ridges. A synclinal apex of Pocono was ascended
over Herndon, on the Susquehanna, then a train ride through
the five water gaps to Harrisburg. A half day was given to
the extraordinary meanders of Conedoquinet creek, and a
morning to the prong of Archean of South Mountain at Read-
ing. Thence the party returned direct to New York by rail.

INCREASED CoAL MINING IN PENNSYLVANIA. In 1891 the
number of bituminous coal mines in operation in Pennsylvania
was 705, while on January 1st, 1901, the number had increased
to 943, an increase of 238, or more than twenty-five per cent.
Somerset and Armstrong counties have doubled the number
of their mines, and Cambria county almost so. In the past
decade Allegheny has gained thirteen; Armstrong, eleven:
Beaver, three ; Bedford, five; Butler, three ; Cambria, fifty-four ;
Center, twelve; Clearfield, six; Elk, nine; Fayette, thirty- -two
Huntingdon, four; Indiana, sixteen; Jefferson, eleven; Somer-
‘set, thirty-four; Washington, six, and, Westmoreland, twenty-
six. The counties showing losses are: Blair, one; Bradford,
three; Mercer, five, and Tioga, three. The remarkable in-
crease has been greater during the priod 1899-1900 than in any
other year of the decade. Captain Baird Halberstadt, of Potts-
ville, formerly assistant geologist of the Geological Survey of
Pennsylvania, has just completed an elaborate and extremely

valuable map of the bituminous coal fields of the state, showing
the undeveloped and developed areas with the location of every
commercial coal mine of these regions—Mines and Minerals.

INDEX TO

Action of Ammonium Chloride on
Natrolite etc, F. W. Clark and
G. Steiger, 49.

Action of Ammonium Chloride on
Analcite and Leucite, F. M. Clark
and G. Steiger, 184.

Adams, F. D. (and J. F. Nicholson),
An experimental investigation into
the flow of marble, 316.

Allen, Thomas W., 327.

Ami, H. M., A national museum for
Canada, 259; Brief biographical
sketch of Elkanah Billings, 225.

American Association for the Ad-
vancement of Science, 387.

American Museum of Natural His-
tory, 389.

ee Copper Mining Company,

Analysis of smithsonite oe Arkan-
sas, W. W. Miller, Jr.,

Analysis of emery from Virginia, W.
W. Miller, Jr., 314.

Analysis of Italian volcanic rocks,
H. S. Washington, 182.

Anderson, F. M., 131.

Andrews, FE. C., Notes on the lime-
stones and general geology of the
Fiji islands, 256.

A new meteorite from Oakley, Logan
county, Kansas, H. L. Preston, 50.

Analysis of rocks, Laboratory of the
United meee Geological Survey,
Pe W. Clark.

A record of the ne of Texas for
the decade ending Dec. 31, 1896,
F. W. Simonds, 57.

A Rae seule marl lake, C. A. Davis,
1

Are the amygdaloidal melaphyrs of
the Boston basin intrusive or con-
temporaneous, W. O. Crosby, 323.

Are the St. John plant beds Carbon-
iferous? G. F. Matthew, 383.

A single occurrence of glaciation in
Siberia, C. W. Purington, 45.

A text-book of important minerals
and rocks, S. FE. Tillman, 48.

Barrett, FE. L., The Sundal drainage
system in Central Norway, 123.

Barton, Geo. H., 327.

Beede, J. W., 387.

Bertiage Pus ‘Burtheiling der Brachi-
opoden, 1

Beitrage zur Burtheiling der Brachi-
opoden, 183.

Beitrage zur Kenntniss des Siberis-
chen Cambrium, FE. von Toll, 54.

Bell, Robert, 263.

VOL. XXVII.

a ae Collection of minerals, 63,

Billings memorial portrait, 198.

Bishop, 8S. E., Brevity of Tuff-cone
eruption, 1.

Blake, W. P. 130; Some salient fea-

tures in the geology of Arizona,
with evidences of shallow seas in
Paleozoic time, 169.

Bownocker, J. A., 327.

Branner, J. C., Geology in its rela-
tions to Topography, 257.

Brevity of Tuff-cone truption, S. E.
Bishop, fe

Brief pinciasiitedt sketch of Elkanah

Billings, H. M. Ami, 225.

Brief review of the titaniferous mag-
netites, J. F. Kemp, 119,

Brooks, A. H., 64.

Brooks, T. B., Obituary notice, 263.

Buchan, J. S., Was mount Royal an
active volcano? 313.

Bulletin of the Hadley laboratory of
the University of New Mexico, C.
L. Herrick, 58.

Bumpus, H. C., 64.

Burr, H. T., Structural relations of
the melaphyrs of the Boston basin,

Calecareous concretions
point, R. A. Daly, 253.

Calvin, 8., 327; Concerning the oc-
currence of gold and some other
mineral products in Iowa, 363.

Cambro-Silurian limonite ores of
Pennsylvania, T. C. Hopkins, 50.

Carnotite and associated vanadifer-
ous minerals in western Colorado,
W. F. Hillebrand and F. L. Ran-
some, 183.

Cerrillos anthracite mines,

Chemical composition of
halite, S. L. Penfield, 50.

Chemical composition of turquois, 8.
L. Penfield, 50.

Chemical study of the Glaucophane
schists, H. S. Washington, 184.

of Kettle

264.
sulpho-

Chirk. /C. W., 197.

Clark, F. W. (and G. Steiger). The
action of ammonium chloride on
natrolite, ete., 49.

Clark, .F. W., Analyses of rocks, U.

S. geological survey, 316.

Clark, F. W. (and G. Steiger). Ac-
tion of ammonium chloride on
analcite and leucite, 184.

Classification of igneous rocks, W.
H. Hobbs. 52.

Claypole, E. W., 130: Notes on
petroleum in California, 150.

Coal mining in Pennsylvania, 390.

392 Index.

Composition of Kulaite, H. S. Wash-
ington, 187.

Concerning the occurrence of goid
and some other mineral products
in Iowa, S. Calvin, 363.

Contact metamorphism of a_ basic
igneous rock, U. 8. Grant, 51.
Contributions to the geology of
Maine, H. S. Williams and H. E.

Gregory, 256.

Contributions to the Tertiary fauna
of Florida, W. H. Dall, 179.

Contribution to the natural history
of Marl, C. A. Davis, 185.

CORRESPONDENCE.

41, 188, 258, 3238, 383.

Croll’s Theory redivivus, 174.

Crosby, W. O. Geology of the Boston
basin—The Blue Hills complex
179: Are the amygdaloidal mela-
phyrs of the Boston basin intru-
sive or contemporaneous? 324.

Cummings, E. R., Orthothetes mi-
nutus, n. sp. from the Salem lime-
stone of Harrodsburg, Indiana,
147.

Dale, T. Nelson, 327.

Dall, W. H., The structure of Dia-
mond Head, Oahu, 386.

Dall, W. H., Contributions to the
Tertiary fauna of Florida, 179.
Daly, R. A., 129; Caleareous con-
eretions of Kettle point, 2538;
Physiography of Acadia, 316.

Darton, N. H., 388.

Davis, C. A., A contribution to the
natural history of marl, 185; A
remarkable marl lake, 188.

Davis, W. M., 390.

Dawson, Geo. M., Obituary notice,
264.

Derby, O. A., Mode of occurrence of
topaz, 185.

Dresser, John A., On the _ Petro-
graphy of Mount Orford, 14.

Dupare’s relief models of the struc-
tures of the Alns, 66.

ES “

EDITORIAL COMMENT.

Croll’s Theory redivivus, 174.

Pleistocene geology of northern
and central Asia, 311; Museum
catalogues, 371: Contributions
to the literature of volcanoes,
874: Gilbert’s summary history
of Niagara falls, 375; The term
Hudson River, 377.

Eighth session of the International
congress of geologists, Paris, 1900,
P. Frazer, 335.

Emerson, B. K., The geology of
Eoetere Berkshire county, Mass.,
od.

Examination of sandstone from Au-
gusta county, Virginia, W. W.
Miller, Jr., 315.

- Experimental investigation into the
flow of marble, F. D. Adams and
J. T. Nicholson, 316.

Explorations in Alaska, 389.

Face de la terre (Antlitz der Erde),
FE. Suess, 56.

Fairbanks, H. W., 131.

Field Columbian Museum, 196.

Field work methods in geology at
Harvard, 329.

Foote, W. M., Occurrence of native
lead with copper and other min-
“oe at Franklin Furnace, N. J.,
82.

Ford, W. E. (S. L. Penfield and),
Siliceous calcites from the bad
lands of South Dakota, 51.

FOSSILS.

Aulacamerella ,47; Craniaden der
Ostseelander, 47; New_ species
from Cape Breton, 49; New gen-
era and snecies from Missouri,
343; Lophoblastus, new species,
345; Carpenterioblastus, n. spe-
cies, 347; Aorocrinus, new spe-
cies, 348.

Frazer, P., Eighth session of the In-
ternational Geological Congress,
Paris, 1900, 335.

Garwood, E. J., 263.

Geological Society of America, 129.

Geological Society of Washington,
129, 194, 263,327, 389

Geological Survey of Canada, 327.

Geological Survey of Missouri, 327.

Geological Survey U. S8., 387.

Geology at Harvard University, 64.

Geology of eastern Bershire county,
Mass., B. K. Emerson, 59.

Geology of the Little Belt moun-
tains, W. H. Weed. and L. >
Pirsson, 254

Geology in its relations to Topog-
raphy, J. C. Brauner, 257.

Geology of the Boston basin—The_
Blue Hills complex, W. O. Crosby, —

179.

Geology of the Tallulah gorge, 8S. P.
Jones, 67.

Gould, C. N., Notes on the Texas-
Oklahoma-Kansas gypsum hills,188.

Granite-gneiss area in Connecticut,
L. G. Westgate, 121.

Granite monoliths, 66.

Granitie rocks of Georgia and their
relationships ,T. L. Watson, 199.
Granitic rocks of the Pike’s_ peak
quadrangle, E. B. Matthew, 254.
Granites of southern Rhode Island
and Connecticut, J. F. Kemp, 51.
Grant, U. S., Contract metamor-
phism of a basic igneous rock, 51.
Gratacap, L. P., 64; Paleontological

speculations, 75.

Gregory, H. E. (and H. S. Wil-
liams), Contributions to the geol-
ogy of Maine, 256; 263; 327.

Gregory, J. W., 65; Plan of the
Earth and its causes, 100, 134.

Gresley. W. S., Possible coal-plants,
ete., in coal, 6; 327.

H
Haeckel, Ernst, 388.

Harker, Alfred, Igneous rock series

and mixed rocks, 123.

Hatcher, J. B., The lake systems of
southern Patagonia, 167; Some
new and little known fossil ver-
tebrates, 379.

Hamilton. I. H., Troost’s survey of
Philadelphia, 41: Progress’ of
mineralogy in 1899, 48.

Herrick, C. L., Bulletin of the la-
boratory of the University of
New Mexico, 58.

Index.

Hershey, O. H., Peneplains of the
Orank highland, 25; Metamorphic
formations of northwestern Cali-
fornia, 225; On the age of cer-
tain granites in the Klamath
mountains, 258.

Hess, W. H., The origin of nitrates
in cavern earths, 122.

Hidden, W. E., Sperrylite in North
ed 182

Hilgard, W., 131; Historical out-
line oa the geological and agri-
vaca survey of Mississippi,

Hillebrand, W. F. (and F. L. Ran-

som), Carnotite in we stern Colo-
rado, 185; Some principles of rock
analysis, 315.

Historical outline of the geological
and agricultural survey of the
state of Mississippi, IE. W. Hil-
gard, 284

reine W. H., Suggestions regarding
ey classification of igneous rocks,

Hopkins, T. C., Cambro-Silurian li-

papeee ores of Pennsylvania, 50;
‘.

Hoyningen-Hueme, Baron von, Ueber
Aulacamerella, 47; Supplement
an der Beschreibung der Silur-
ischen Craniaden der Ostseelan-
der, 47.

Hubbard, Ee, 64:

Huene, F., Beitrage zur Burtheiling
der Brachiopoden, 183; JHleine
Mittheilungen, 184.

feneous complex of Magnet Cave,
Arkansas, H. S., Washington, 121.
Igneous rock series and mixed rocks,
A. Harker, 123.
Irving, J. D., Some contact phe-
: oe of the Palisade diabase,
53.
J

, The geology of the Tal-
lulah erie 2

Jovellania triangularis in Mittelde-
von der Wifel, E. Kayser, 119.

Kayser, F., Ueber grosse flache Ue-
berschiebungen in Diilgebier, 54 ;
Ueber den nassauischen Culm, 5.
Jovellania triangularis in Mittel-
devon der Fifel, 119.

Kemp, J. F., Granites of southern
Rhode Island and Connecticut,
51: Brief review of the titanifer-
ous magnetites, 199.

Keyes, C. R., Ore formation on the
hypothesis of concentration
nes surface decomposition,

Kleine, Mittheilungen
ische, F. Huene, 184.

Kuntze, Otto, 198.

Jones, S.

paleontolog-

eB
Lacoe, R. . 198.
met Superior iron trade for 1900,
vw.

Lake systems of southern Patagonia,
f Hatcher, 167.
Lawson, A. C., 132.

393

Lehigh University, 389.
Leverett, Frank, 196.
Low, A. P., 198.
Lucas, F._A., 196.
Luqueur, L. M., 129.

Martin, J. O., The Ontario coast be-

he Fairhaven and Sodus bays,
+ Vo

McCalley, H., 388.

McCallie, 8. W., Some notes on the
trap dikes of Georgia, 133.

Matthew, KE. B., Granitic rocks of
the lage 3 S peak quadrangle, 254.

Matthew, lk., New species of Cam-
brian fossils from Cape Breton,
49; Are the St. John plant beds
Carboniferous? 383.

Merriam, J. C., 132:
Merrill, ‘G. jes 389.
Metamorphic formations of north-

western California, 0. H. Hershey,

es PAs

Miller, W. G.; On some newly dis-
covered areas of nepheline syen-
yte in central Canada, 21.

Miller, W. W., Jr., Analysis of em-
ery from Virginia, 314; Examina-
tion of sandstone from Augusta
county, Virginia, 315; Analysis of
smithsonite from Arkansas, 315.

MINERALS.

Tillman’s text-book, 48; Natrolite,
scolicite, prehnite, pectolite,
acted on by Ammonium chlor-
ide, 49; Turquois, 50; Sulpho-
halite, 50; Siliceous calcites,
51; Bement collection, 63; Na-
tive lead and copper at Franklin
Furnace, 182; Sperrylite in
North Carolina, 182; 'Thomson-
ite, etc., from Golden, Colo.,
183 ; Mode of occurrence of to-
paz, 185; Carnolite in Colorado,
185; Barytocelestile, 315.

Mode of ‘occurrene of topaz near
Ouro Preto, O. A. Derby, 185.
Monthiy Author’s Catalogue of

American Geological literature,
59, 129, 190, 260, 320, 380.
Morgan, J. Pierpont, 328.
Mother - Lode district,
Folio 36, 65.
Moses, A. H., 129.

California,

National museum for Canada, H. M.
Ami, 259, 328.

Neutaconkanut boulder, 329.

New species of ;Cambrian fossils
ris Cape Breton, G. IF. Matthew,

New York Academy of Sciences, T.
G. White, 42.

Nicholson, J. T. (F. D. Adams and),
An experimental investigation in-
to the flow of marble, 316.

Nomenclature of feldspathic grano-
lites, H. W. Turner, 53.

Notes on the Kansas-Oklahoma-Tex-
as gypsum hills, C. N. Gould, 188.

Notes on the limestones and general
geology of the Fiji islands, BE. C.
Andrews, 25.

Notes on petroleum in California, FB.
W. Claypole, 150.
Notes on the telurides

rado, C. Palache, 181.

from Colo-

304 Index.

Occurrence of native lead and cop-
per, with other minerals at Frank-
lin Furnace, N. J., W. M. Foote,
182.

O’Harra, C. C., Bulletin of the South
Dakota School of Mines, 124.

Osborn, H. F., 65; Phylogeny of the
Rhinoceroses of Europe, 879; 389.

On some newly discovered areas of
nepheline syenyte in central Can-
ada. W. G. Miller, 21.

Ontario coast between Fairhaven
and Sodus bays, N. Y., J. O. Mar-
tin, 33

On the age of certain mountains in
the Klamath mountains, O. H:
Hershey, 258.

On the constitution of _barytoceles-
tite, C. W.. Volney,, 315.

On the Helderberg fossils near Mon-
treal, Canada, C. Schuchert, 245.

Ore formation on the hypothesis of
concentration through surface de-
composition, C. R. Keyes. 355.

Original micaceous cross-banding of
strata by current action, J. B.
Woodworth, 281.

Origin of Kaolin, H. Ries, 120,

Origin of nitrates in cavern earths,
W. H. Bess) 22.

Orthothetes minutus, _n. sp., from
the Salem limestone of Harrods-
burg, Indiana, I. R. Cummings,
147.

Owen, L. A., 387.

Palache, C., Notes on the tellurides
from Colorado, 181.

Patton, H. B., 129; Thormisonite,
mesolite and chabazite from Gol-
den, Colo., 185-6.

-aleontological speculations, L. P.
Gratacap, 75.

Peneplains of the Ozark highland,
O. H. Hershey,. 25.

Penfield, S. L.. Chemical composi-
tion of turouois, 50: Of sulpho-
halite, 50: Siliceous calcites, 51.

Penrose, R. A. F., 328.

Petrography of Mount Orford, J. A.
Dresser, 14.

Phylogeny of the Rhinoceroses of
Europe, H. F. Osborn, 379.

Physiography of Acadia, R. A. Daly,
316.

Pirsson, L. V. (and W. H. Weed),
Geology of the Little Belt moun-
tains, 254 .

Plan of the earth and its causes, J.
W. Gregory, 100, 134.

Pleisocene geology of northern and
central Asia, 311.

Possible coal vlants, ete., in coal,
W. S. Gresley, 6.

Preston, H. L., A new_ meteorite
from Oakley, Kansas, 50.

Purington. C. W.. A single occur-
rence of glaciation in Siberia, 45.

Ransome, F. L., 66; (and W. \F.
Hillebrand), Carnotite in western
Colorado, 185.

Researches on the visual organs of
trilobites, G. Lindstrom, 258.
REVIEW OF GEOLOGICAL LITERATURE.

47. 119, 179, 253, 3138; 397:

Ries, H., The origin of Kaolin, 120.

Rothwell, RK. P., Obituary notice,
a PAE ip

Row. 18% R. R., Two new genera and
some new species of fossils from
the upper Paleozoic rocks of Mis-
souri, 5458.

Salient features in the geology of
Arizona, with evidences of shallow
seas in Paleozoic time, W. P.

_ Blake, 160.

Schuchert, C., On the Helderberg fos-
sils near Montreal, Canada, 245.

Scott, W. B., 263.

Simonds, F. W., A record of the ge-
ology of Texas for the decade end-
ing, Dec. 31, 1896, 57.

Smith, W. 8S. Tangier, Topographic
study of the islands of southern

_ California, 187.

Some contact phenomena of the Pal-
isade diabase, J. D. Irving, 53.
Some new and little known fossil
vertebrates, J. B. Hatcher, 319.
ts notes on the trap dikes of
Georgia, S. W. McCallie, 138.
Some principles of rock analysis, Ws

I. Hillebrand, 315.

Spendiaroff prize, 330.

Sperrylite in North Carolina, W. E.
Hidden, 182.

Spurr, Jie Bs 19

Steiger, G. (F. W. Clark and), Ac-
tion of ammonium chloride on
natrolite, ete. 49; Oon analcite
and leucite, 184.

Structural relations of the amyg-
daloidal metaphyrs of the Boston
basin; \H209s) Burr roles

Suess, E., La face de la terre (Ant-
litz der Erde), 56.

Summary renort of the geological
report of Canada for 1901, 313.
Sundal drainage system in central

Norway, 123.

Supplement an der Beschreibung der
Silurischen Craniaden der Ost-
seelander, * Baron Hoyningen-
Iluene, 47.

The structure of Diamond Head,
Oahu, W. H. Dall, 386.

Thomsonite, mesolite and chabazite
from Golden, Colo., H. B. Patton,
Oo.

Tillman, S. E., A text-book of im-
portant minerals and rocks, 48.
Topographic study of the islands of
southern Calfornia, W. 8S. Tangier

Smith, 187.

Tribute to Victoria, 197.

Troosts survey of Philadelphia, 8.
H. Hamilton, 41.

Toll, .. von, Beitrage zur Kenntniss
des Siberischen Cambrium, 54.
Turner, H. W., Nomenclature of
feldspathic granolites, 53; 132.
Two new genera and some new spe-
cies of fossils from the upper
Paleozoic rocks of Missouri, R. R.

Rowley, 348.

Ueber Aulacamerella,
Tluene, 47.

Ueber grosse flache Ueberschiebun-
gen in Dillgebiet, IE. Kayser, 54.

Hoyningen-

{
4
J
.

Index.

pails Nassauischen Culm, MKayser,

ot.
United States Geological Survey, 65,

’

Van Hise, C. R., 388.

Vogdes, A. W.

Volney, C. W., On the constitution
of barytocelestite, 315.

Ward-Coonley collection of meteor-
ites, 388.

Washington, H. 8., Igneous complex
of Magnet cove, Arkansas, 121;
Analysis of Italian volcanic rocks,
182; Chemical study of the Glau-
cophane schists, 184; Composition
of kulaite, 187.

395

Was Mount Royal an active volcano?
J. S. Buchan, 313.
Watson, IT. L., The granitic rocks of
veo ee and their relationships,
9

Weed, W. H., 197; Geology of the
Little Belt mountains, 254.

Westgate, L. G., A granite-gneiss
area in Connecticut, 121.

Weston, T. C., 66.

White, Theo. D. New York Academy
of Sciences, 42.

Whitfield, R. P., 887.

Williams, E. H., Jr., 129.

Williams, H. S. (and H. E. Greg-
ory), Contributions to the geol-

ogy or Maine, 256.

Withrow, James R. (8S. H. Hamilton

and), Progress of Mineralogy in
1899, 48.
Woodworth, J. B., Original mica-

ceous cross-banding of strata by
current action, 281; 387.

Errata for Volume XXVI

On p. 309, line 9 from bottom instead of “Wachsmuth Collection” read
Wachsmuth and Springer Collection.
On p. 310, line 17, instead of “statements” read statement.

Errata for Volume XXVIII

On p. 258, for

3 line

line

On p. 320, line 7
tion.

On p. 330, line 7 from the top, for

“

“Petiera” read Peltura.

18, for “Ctinopyge” read Ctenopyge.

22, for “Solmopleura” read Solenopleura.
29, for “‘this” read the.

from the bottom, for “decomposition”

read deposi-

voleanic” read vein.

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