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BULLETIN

OF THE

GEOLOGICAL SOCIETY

AMERICA

VOL. 26

JOSEPH STANLEY-BROWN, Editor

NEW YORK

PUBLISHED BY THE SOCIETY

1915

\1(:)

OFFICERS FOR 19J5

Vice-Preside?i is

Arthur P. Coleman, President

L. V. PiRSSON,

H. P. Gushing.

E. 0. Ulrich. J
Edmund Otts Hovey, Secretary
William Bullock Clark. Treasure
Joseph Stanley-Brown, Editor

F. R. Van Horn, Librarian

Class of 1917
Charles K. Leith,
Thomas L. AVatson..

Class of 1916
E. A. P. Penrose, Jr., !- Councilors
W. W. Atwood,

Class of 1915
Whitman Cross,-
Willet G. Miller,

Printers
JuDD & Detweiler (Inc.), Washington, D. C.

Engravers
The Maurice Joyce Engraving Company, Washington, D. C.

CONTENTS

Page
Proceedings of the Tweut^-seventli Annual Meeting of the (Geological
Society of America, lield at Ptiiladelpliia, Pennsylvania, December 29,

30, and 31, 1914 ; Edmund Otis Hovey, Secretarn 1

Session of Tuesday, December 29 4

Report of the Coiuicil 5

Secretary's report 5

Treasurer's report 8

Editor's report 10

Election of Auditing Committee 11

Election of officers 11

Election of Fellows 12

Memoir of Alfred Ernest Bai-low (with bibliography) ; by Frank

D. Adams 12

Memoir of Albert S. Bickmore ; by George F. Kunz IS

Memoir of Horace C. Hovey (with bibliography) ; by John M.

Clarke 21

Memoir of Newton Horace Winchell (with bibliography) ; by

Warren Uph am 27

Memoir of Joseph Le Conte (with bibliography) ; by Herman L.

Fairchild 47

Report of Committee on Photographs 57

Report of Committee on Geological Nomenclature 57

Titles and abstracts of papers presented in general session and

discussions thereon 5S

Relation of bacteria to deposition of calcium carbonate [ab-
stract] ; by K^VRL F. Kellerman 58

Coral reefs and reef corals of the southeastern United States,
their geologic history and significance [abstract and dis-
cussion] ; by Thomas Wayland Valgiian 58

Causes producing scratched, impressed, fractured, and rece-
mented pebbles in ancient conglomerates [abstract and dis-
cussion] ; by John M. Clarke 60

Titles and abstracts of papers presented before the First Section

and discussions thereon 61

Origin of the Red Beds of western Wyoming [abstract and

discussion] ; by E. B. Branson 61

New points on the origin of dolomites [abstract] ; by Francis

M. Van TuYi 62

Range and rhythmic action of sand-blast erosion, from studies

in the Libyan Desert [abstract] ; by William H. Hobus. . . 63
Corrasive efficiency of natural sand-blast [abstract] : by

Charles Keyks 63

False fault-scarps of desert ranges [abstract] ; by Charles

Keyes 6;'>

Strntigraphic disturbance through the Ohio Valley running
from the Appalachian Plateau in Pennsylvania to the

(iii)

IV BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Page
Ozark Mountains in Missouri [abstract] ; bj' James H.
Gardner 66

Preliminary paper on recent crustal movements in the Lake
Erie region [abstract and discussion] ; by Charles E.
Decker 66

Quaternary deformation in southern Illinois and southeastern
Missouri [abstract]; by Elgene Wesley Shaw 67

Old shorelines of Mackinac Island and their relations to the
lake history [abstract] ; by Frank B. Taylor 68

Some peculiarities of glacial erosion near the margin of the
continental glacier in central Illinois [abstract and discus-
sion] ; by John L. Rich 70

New evidence of the existence of fixed anticyclones above
continental glaciers [abstract] ; by William Herbert
HOBBS 73

Origin of Monks mound [abstract] ; by A. R. Crook 74

Can U-shaped valleys be produced by removal of talus? [ab-
stract] ; by Alfred C. Lane 75

Physiographic studies in the driftless area [abstract] ; by
Arthur C. Trowbridge 76

Hemicones at the mouths of hanging valleys [abstract] ; by
Charles E. Decker 76

Block diagrams of state physiography [abstract] ; by A. K.
LOBECK 77

Kilauea, a drop-fault crater [abstract] ; by George Carroll
Curtis 77

Age as the determinant of character in volcanoes [abstract] ;
by George Carroll Curtis 78

Comprehensive coral island theory [abstract] ; by George
Carroll Curtis 78

Evidence of continental glaciation on Mount Katahdin [ab-
stract] ; by George Carroll Curtis 78

Naturalistic land model, the "last word in geology" [ab-
stract] ; by George Carroll Curtis 79

Second Section 81

Titles and abstracts of papers presented before the Third Section
and discussions thereon 81

Pre-Cambrian igneous rocks of the Pennsylvania Piedmont
[abstract] ; by F. Bascom 81

Magmatic assimilation [abstract] ; by F. Bascom 82

Hypersthene syenite (akeritel of the middle and northern
Blue Ridge region, Virginia [abstract] ; by Thomas Ij.
Watson and Justus H. Cline 82

Pyrrhotite, norite, and pyroxenite from Litchfield, Connecti-
cut [abstract] ; by Ernest Howe 83

Some effects of pressure on rocks and minerals [abstract and
discussion] ; by John Johnston S3

Primary chalcocite in the fluorspar veins of Jefferson County,
Colorado [abstract] ; by Horace B. Patton 84

CONTENTS V

Page

Recent remarkable gold "strike" at the Cresson Mine, Cripple
Creek, Colorado [abstract and discussion] ; by Horace B.

Patton 84

Platinum-gold lode deposit in southern Nevada [abstract] ;

by AuoLPH Knopf 85

(Organic origin of some minei'al deposits in unaltered Paleo-
zoic sediments [abstract and discussion] ; by Gilbert van

Ingen 85

Isostasy and radioactivity ; I'resideutial address by George F.

Becker 86

Session of Wednesday, December 30 87

Report of Auditing Committee 87

Titles and abstracts of papers presented in general session and

discussions thereon 87

Revision of pre-Cambriau classification in Ontario [abstract
and discussion] ; by Willet G. Miller and Cyril W.

Knight 87

North American continent in Upper Devonic time [abstract

and discussion] by Amadeus W. Grabau 88

Symposium on the passage from the Jurassic to the Cretaceous. . 90
Titles and abstracts of papers presented before the First Section

and discussions thereon 90

Type of rifted relict mountain, or rift mountain [abstract

and discussion] ; by John M. Clarke 90

Evidence of recent subsidence on the coast of Maine [abstract

and discussion] ; by Charles A. Davis 91

Basic rocks of Rhode Island : their correlation and relation-
ships [abstract and discussion] ; by A. C. HawkIxXS and

C. W. Bkowx 92

Acadian Triassic fal)stract and discussion] ; by Sidney

Powers 93

(Geological history of the Bay of Fundy [abstract] ; by Sidney

Powers 94

Titles and al)stracts of papers presented before the Second Sec-
tion 95

Alexandrian rocks of northeastern Illinois and eastern Wis-
consin [al)stract] ; by T. E. Savage 95

Olentangy shale and associated deposits of northern Ohio

[abstract] ; by Clinton R. Stauffer 95

Diastrophic importance of the unconformity at the base of

the Berea sandstone in Ohio [abstract] ; by H. P. Cushing. 96
Kinderhookian age of the Chattanoogan series [abstract] ; by

E. O. Ulrich 96

Titles and abstracts of papers presented before the Third Section

and discussions thereon 99

Origin of the iron ores at Kiruna, Sweden [abstract] ; by

Reginald K. 1 » at.y 99

Origin of the Rocky MouiitMiii jihosphate deposits [abstract] :
by Eliot Black welder 100

VI BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

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Regional altei*ation of oil shales [abstract] ; by David White, 101
Oil pools of southern Oklahoma and northern Texas [ab-
stract] ; by James H. Gardner 102

Natural gas at Cleveland, Ohio [abstract] ; by Frank R.

Van Horn 102

Origin of thick salt and gypsum deposits [abstract and dis-
cussion] ; by E. B. Branson 103

Crystalline marbles of Alabama [abstract] ; by William F.

Peouty 104

Annual dinner 104

Session of Thui-sday, December 31 lOo

Titles and abstracts of papers presented in general session and

discussions thereon 105

Present condition of the volcanoes of southern Italy [ab-
stract] ; by H. S. Washington and A. L. Day 105

Recent eruptions of Lassen Peak, California [abstract] ; by

J. S. Diller ' 105

Physiographic study of the Cretaceous-Eocene period in the
Rocky Mountain front and Great Plains provinces [ab-
stract] ; by George H. Ashley 105

Relation of physiographic changes of ore alterations [ab-
stract] ; by Wallace W. Atwood 106

Graphic projection of Pleistocene climatic oscillations [ab-
stract] ; by Chester A. Reeds 106

Geologic deposits in relation to Pleistocene man [abstract] ;

by Chester A. Reeds 109

Physiographic features of western Europe as a factor in the

war [abstract] ; by Douglas W. Johnson 110

Vote of thanks 110

John Boyd Thacher Park: The Helderberg Escarpment as a

geological park [abstract] ; by George F. Kunz 110.

Relief of our Pacific coast [abstract] ; by J. S. Diller Ill

Titles and abstracts of papers presented before the Second Sec-
tion 112

Devonian of central Missouri [abstract] ; by E. B. Branson

and D. K. Greger 112

Olentangy shale of central Ohio and its stratigraphic signifi-
cance [abstract] ; by Amadeus W. Grabau 112

Hamilton group of western New York [abstract] : ))y Ama-
deus W. Grabau 113

Extension of Morrison formation into New Mexico [abstract] ;

by N. H. Daeton 113

Geological reconnaissance of Porto Rico [abstract] ; by

Charles P. Berkey 113

Relation of Cretaceous formations to the Rocky Mountains in

Colorado and New Mexico [abstract] ; by Willis T. Lee.. 114
Post-Ordovician deformation in the Saint Lawrence Valley,

New York [abstract] ; by George H. Chadwick 115

CONTENTS Vll

Page
OfHcers, Correspoixients, and Fellows of the Geological Society of

America 117

I'roceeclings of the Fifteenth Annual Meeting of the Cordilleran Section of
the Geological Society of America, held at Seattle, Washington, May 21

and 22. 1914 ; George D. Louderback, Secretary 129

Session of Thursday, May 21 130

Pre- Pleistocene geology in the vicinity of Seattle [abstract

and discussion] ; by Charles E. Wea\-eb 130

Pleistocene of western Wasliington [abstract] ; by Charles

E. Weaver i;jl

Election of officers 131

Summer meeting 131

Affiliation with the American Association for the Advance-
ment of Science 132

Structure of Pierce County coal field of Washington [ab-
stract and discussion] ; by Joseph Daniels 132

Tertiary rocks of Oahu [abstract and discussion] ; by C. H.
Hitchcock 133

Pea for uniformity and simplicity in petrologic nomenclature

[abstract and discussion] ; by G. Montague Butler 134

Session of Friday, May 22 135

Geologic structure in western Washington [abstract and dis-
cussion] ; by Charles E. Weaver. .* 135

Eocene of the Cowlitz Valley, Washington [abstract and dis-
cussion] ; l)y Charles E. Weaver 130

Relation of the Tertiary geological scale of the Great Basin
to that of the Pacific Coast marginal province [abstract
and discussion] ; by J. C. Merriam 136

Relation between the Tertiary sedimeutaries and lavas of
Kittitas County, Washington [abstract] ; by E. J. Saun-
ders 137

Oregon Bureau of Mines and Geology [abstract and discus-
sion] ; by Ika A. Williams 137

Role of sedimentation in diastrophism and vulcanism ; by

F. M. Handy 138

Basin Range faulting in the northeastern part of the Great

Basin [abstract] ; by George D. Louderback 138

I'roceedings of the Sixth Annual Meeting of the Paleontological Society,
held ;it I'hilndelphia, Pennsylvania, December 29, 30, and 31, 1914:

H. S. P.ASSLEu, Hccrctunj 141

Session of Tuesday, December 29 144

Report of the Council 114

Secretary's report 1 H

Treasurer's report It''

Appointment of Auditing Committee 1 "'

Election of officers and members H<>

Election of new members 11"

Cliapter on iwileontology of man 147

VIU BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Pago

New business and announcements 147

Presentation of general papers 148

Occurrence of algal and bacterial deposits in the Algonkian
Mountains of Montana ; by Charles D. Waxcott 148

Fossil algfe of the Ordovician iron ores of Wabana, New-
foundland ; by Gilbert Van Ingen 148

Migration and succession of human types of the Old Stone
Age of Europe ; by Henry F. Osborn 149

Restorations of Pithecanthropus and Piltdown and Neander-
thal man ; by J. H. McGregor 149

Evidence proving that the Belly River beds of Alberta are
equivalent to the Judith River beds of Dog Creek and Cow
Island, Montana [abstract] ; by Charles H. Sternberg. . . . 149

Session of Wednesday, December 30 150

Completion of papers of general interest 150

Shawangunk formation of Medina age [abstract] ; by
Charles Schuchert 150

Pic d'Aurore section ; by John M. Gierke 150

Peccaries- of the Pleistocene of New York; by John M.

Clabke and W. D. Matthew 150

Symposium on the passage from the Jurassic to the Cretaceous. . 151

Introduction ; by Henry Fairfield Osborn 151

The Morrison ; an initial Cretaceous formation ; by Wlllis
T. Lee 151

Geologic exposure of the Morrison ; by Charles C. Mook .... 151

Sauropoda and Stegosauria of the ^Morrison compared with
that of South America, England, and eastern Africa ; by
Richard S. Lull. 151

The paleobotanic evidence ; by Edward W. Berry 151

The invertebrate fauna of the Morrison; by T. W. Stanton. 151
The addition and evolution of "characters" in paleontologic phyla ;

Presidential address by Henry Fairfield Osborn 151

Section of Vertebrate Paleontology 151

Megalocnus and other Cuban ground-sloths [abstract] ; by
Carlos de la Torre and W. D. Matthew 152

Affinities of Hyopsodus [abstract] ; by W. D. Matthew 152

New evidence of the affinities of the Multituberculata [ab-
stract] ; by Walter Granger 152

Heads and tails ; a few notes relating to sauropod dinosaurs
[abstract] ; by W. J. Holland 153

Observations on Adapidse and other Lemuroidea ; by W. K.
Gregory 153

Observations on the phylogeny of the higher Primates [ab-
stract] ; by W. K. Gregory 153

Reconstruction of the skeleton of Brachiosaurus [abstract] ;
by W. D. Matthew 153

Fish fauna of the Conodont bed (basal Genesee) at Eighteen-
mile Creek. New York ; by L. Hussakof and W. L. Bryant. 154

CONTENTS IX

Page

Stratigraphic relations of the fossil vertebrate localities of
Florida [abstract] ; by E. H. Sellabds 154

Scaled Amphibia of the Coal Measures; by Roy L. Moodie... 154
Section of invertebrate, paleobotanic, and general paleontology . . . 154

Alexandrian roclis of northern Illinois and eastern Wiscon-
sin ; by T. E. Savage 155

Diastrophic importance of the unconformity at the base of
the Berea sandstone in Ohio ; by H. P. Gushing 155

Kinderliookian age of the Chattanoogan series; l>y E. O.

Ulkicii 155

Session of Thursday, December 31 155

Devonian of central Missoui'i ; by E. B. Branson and D. K.
Gregok 15(i

Olentangy shale of central Ohio and its stratigraphic signifi-
cance [abstract] ; by A. W. Grabau 156

Geological reconnaissance of Porto Rico ; by Charles P.
Berkey 156

Relations of Cretaceous formations to the Rocky Mountains
in Colorado and New Mexico ; by Willis T. Lee 156

Evolution of the Anthozoa and the systematic position of
Paleozoic corals [abstract] ; by T. C. Brown ' 157

New facts bearing on the I'aleozoic stratigraphy of the region
about Three Forks, Montana [abstract] ; by W. P. Haynes. 157

Studies of tlie morphology and histology of the Trepostomata
(Mouticuliporoids) [abstract] ; by E. R. Cumings and J. J.
Galloway 158

Hamilton group of New York [abstract] ; by A. W. Grabau. . 158

A classification of aqueous habitats [abstract] ; by Marjorie

O'CONNELL 159

New species of Ficus from tlie interglacial deposits of the
Kootenay Valley, British Columbia [abstract] ; by Arthur

HOLLICK 159

Officers, correspondents, and members of the Paleontological Society. . 160
Minutes of the Fifth Annual Meeting of the Pacific Coast Section of

the Paleontological Society ; C. A. Waring, Secretary 166

Election of officers 166

Papers of the Stanford Meeting 166

Note on the Cretaceous Ecliinoderms of California ; by W. S.

W. Kew 166

RelatiDUs of the Santa Margarita formation in the Coalinga

East Side Field [abstract] ; by John H. Ruckman 166

Tentative correlation table of the Neocene of California ; l).\-

BRurt; L. Clark 1(17

Faiuia <tf the Lower Monterey of Contra Costa County, Cali-
fornia ; l)y Bruce L. Clark 167

Extinct toad from Rancho La Brea |al)stract]; by Charlks

L. Camp I(i7

Rodents of Rancho La Brea [abstract] ; by Lee R. Dice Hi"

X BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Page
Occurrence of mammal remaius in the asphalt beds of Mc-

Kittrick, California [abstract] ; by Neill C. Cor>'\vall 167

Outline of the history of the Castoridiie [abstract] ; by W. P.

Taylor 161

Ci etaceous-Eocene contact in the Atlantic and Gulf Coastal

Plain [abstract] ; by L. W. Stephenson 168

lone formation of the Sierra Nevada foothills, a local facies
of the Upper Tejon-Eocene [abstract] ; by Roy E, Dickeb-

soN 168

Stratigraphic and faunal relations of the later Eocene of the

Pacific [abstract] ; by Harold Hannibal 168

Fauna and relations of the white shales of the Coalinga Dis-
trict ; by John H. Ruckman 168

Vertel)rate fauna in the marine Tertiary of California ; their
significance in determining the age of California Tertiary

. formations ; by J. C. MERRLi.M 168

Geology of a portion of the McKittrick oil field; by G. C.

Gester 169

Papers of the University of Washington Meeting 169

Stratigraphic and faunal relations of the Lincoln formation

in Washington ; by Charles E. Weaver 169

Cretaceous faunas of the Santa Ana Mountains [abstract] ;

by Earl L. Packard 169

Review of the fauna of the Rattlesnake Pliocene of eastern

Oregon [abstract] ; by John C. Merriam 169

Eocene of the Cowlitz Valley ; by Charles E. Weaver 169

Fauna of the Siphonalia sutterensis zone in the Roseburg

quadrangle, Oregon [abstract] ; by Roy E. Dickerson 169

Evolution of the Pacific Coast Mactridfe [abstract] ; by Earl

L. Packard 170

Correlation of the Tertiary formations in western Washing-
ton ; by Charles E. Weaver 170

Isostasy and Radioactivity; Presidential address by George F. Becker... 171
Diastrophic importance of the unconformity at the base of the Berea grit

in Ohio ; by H. P. Gushing 205

Origin of the Red Beds of western Wyoming; by E. B. Branson 217

Origin of thick gypsum and salt deposits ; by E. B. Branson 231

Length and character of the earliest inter-Glacial period; by A. P. Cole-
man 243

Obsidian from Hrafntinnuhryggur, Iceland : its lithophj^sre and surface

markings ; by Fred. E. Wright 255

Post-Ordovician deformation in the Saint Lawrence Valle3% Xew York ;

by George H. Ch^u)wick 287

Close of Jurassic and opening of Cretaceous time in North America ; by

Henry Fairfield Osborn 295

Reasons for regarding the Morrison an introductory Cretaceous formation ;

by Willis T. Lee 303

Origin and distribution of the Morrison formation; by Charles C. Mook. 315

CONTENTS XI

Page

Sauropoda aud Stegosauria of the Morrison of North America compared

with those of Eliirope and eastern Africa ; by Richard Swann Lull. . . . 323
I'aleobotanic evidence of the age of the Morrison formation ; l)y Edward

WiLBER Berry 335

Invertebrate fauna of the Morrison formation; by T. W. Stanton 343

Studies of the morpliology and liistology of the Trepostomata or Monti-

culiporoids ; by E. R. Cumixgs and J. J. Galloway 349

Present condition of the volcanoes of southern Italy ; by H. S. Washing-

Tox and Arthur L. Day" 375

Proceedings of the Summer Meeting of the Geological Society of America,
held at the University of California and at Stanford University, August

3, 4, and 5, 1915 ; J. A. Taff, Secretary pro tern 389

Session of Tuesday, August 3 390

Titles and abstracts of papers presented and discussions thereon . 391
Epigene profiles of the desert [abstract and discussion] ; by

Andrew C. Lawsox 391

Bajadas of the Santa Cataliua Mountains, Arizona [abstract

and discussion] ; by C. F. Tolman, Jr 391

Origin of the tufas of Lake Lahontan [abstract] ; by J. C.

Jones 392

Some physiographic features of bolsons [discussion] ; by

Herbert E. Gregory 392

Sculpturing of rock by wind in the Colorado plateau prov-
ince ; by Herbert E. Gregory 393

Session of Wednesday. August 4 393

Titles aud abstracts of papers presented and discussions thereon . 393
Some chemical factors affecting secondary sulphide ore en-
richment [abstract and discussion] ; by S. W. Young 393

Role of colloidal niigratiou in ore deposits [abstract and dis-
cussion] ; by John D. Clark 394

Examples of progressive change in the mineral composition
of coppei- ores [abstract ;ind discussion] ; by C. F. Tolman,

Jr 394

Sericite, a low tempei-ature hydrothermal mineral [ab.stract] :

by A. F. Rogers 395

Dinner 395

Session of Thursday. August 5 395

Titles and abstracts of papers presented and discussions thereon. 395
Physiographic control in the Philippines [abstract and dis-
cussion] ; by Warren D. Smith 395

Origin of the Iiasins within the hamada of the Libyan Desert

[abstract] : by William H. Hobbs 396

Tiimited effective vertical range of the desert sand-blast,
based on ob.serviitions made in the Libyan Desert and in the
.\nglo-Egypfi;in Sudan [abstract]; )>y William H. IIorbs.. 396
Characteristics of the Lassen Peak eruptions of May 20-22.
1915 [abstract iind discussion] ; by Ruliff S. Holway and
J. S. Dtt T,r R .397

Xll BULLETIN OF THE GEOLOGICAL SOCIETY OV AMERICA

Page
Geology of portions of western Washington [abstract] ; by

Ch^vrles E. Weaver 397

Problem of the Texas Tertiary sands [abstract] ; by E. T.

DUMBLE 393

Pisolites at San Antonio, Texas [abstract] ; by Alexander

Delssen 398

Geologic age of the Coal Creek batholith and its bearing on
some other features of the geology of the Colorado front

range [abstract and discussion] ; by Hyrum Schneider 398

Occurrence of tiow-breccias in Colorado [abstract and discus-
sion] ; by Horace B. Pattox 399

(xeology of a portion of the Santa Ynez River district, Santa

Barbara County, California [abstract] ; by W. S. W. Kew. 401
Interesting changes in the composition of the Salton Sea [ab-
stract] ; by A. E. Vinson 402

Examples of successive replacement of earlier sulphide min-
erals by later sulphides at Butte. Montana [abstract and

discussion] : by J. C. Ray 402

Structure of the southern Sierra Nevada [abstract] ; by John

P. BULWADA 403

A measure of arid erosion [abstract] ; by Charles Keyes... 404
A possible causal mechanism for heave fault-slipping in the
California Coast Range region [abstract] ; by Harry O.

Wood 404

Structural features of the Tsin Ling Shan [abstract] ; by

George D. Louderback 405

Certain structural features in the coal fields of New Mexico

[abstract] ; by Charles T. Kirk 405

Deformation of the coast region of British Columbia [ab-
stract] ; by Charles H. Clapp 406

Study of ninety thousand pounds of mammoth tusks from

Lena River, Siberia ; by George Frederick Kunz 407

Excursions 4O7

Proceedings of the Summer Meeting of the Paleontological Society, held
at the University of California and at Stanford University, August 3,

4, 5, and 6, 1915 ; Chester Stock, Secrctanj pro tern 409

Session of Tuesday, August 3 410

Criteria of correlation from the point of view of the inverte-
brate paleontologist ; by Edward O. Ulrich 410

Problem of correlation by use of vertebrates ; by William D.

Matthew 4II

Correlation and chronology on the basis of paleography; by

Charles Schuchert 411

Discussion of the preceding three papers 411

Session of Wednesday. August 4 412

Relations of the invertebrate faunas of the American Triassic
to those of Asia and Europe [discussion] ; by James
Perrin Smith 412

CONTENTS xni

Page

Triassic deposits of Japan [discussion] ; by H. Yabe 413

Correlation between tlie terrestrial Triassic forms of western

North America and Europe [discussion] ; by Richard S.

Lull 413

Comparison of marine vertebrates of western North America

with those of other Triassic areas; by John C. Merriam. . 413

Dinner 413

Session of Thursday, August 5 413

Correlation between the Cretaceous of the Pacific area and

that of other regions of the world ; by Timothy W. Stanton 414
Correlation of the Cretaceous invertebrate faunas of Cali-
fornia : by Timothy W. Stanton 414

Correlation between invertebrate faunas of California and

those of Mexico ; by Earl L. Packard 414

Comparison of the Cretaceous faunas of Japan with those of

western United States ; by H. Yabe 414

Comparison of the Cretaceous floras of California with those

of other Cretaceous areas : by F. H. Knowlton 414

Discussion of the preceding five papers 414

Session of Friday, August 6 415

Introductory remarks on correlation of Miocene ; by Henry

Fairfield Osborn 415

Correlation of the I-ower Miocene of California ; by Ralph

Arnold 415

Review of the Miocene and Oligocene faunas of California :

by B. L. Clark 410

Miocene of the Washinglon-Oregon province and its relation

to that of Califoi-nia and other IVIiocene areas: by Charles

E. Weaver 416

Vertebrate fa\nias of the Pacific Coast region; by John C.

Merriam 410

Correlation lietween the Middle and late Tertiary of the

South Atlantic coast of the United States with that of the

Pacific coast ; by K. H. Skllakds 410

Relation of the Miocene niannnalian faunas of western

United States to those of Eufope and Asia; by William I).

Matthew 410

Correlation of the Miocene floras of western T^nited States

witb Miose of other Miocene areas; by F. H. Knowlton... 410

Fh)ra ..f FlorissiHit : l)y T. D. A. Cockereli 410

Faunal geogmpby of tlic Eocene of California; by R. E.

DiCKKKSO.N 410

Recent work uii (lie dinosaurs of the Cretaceous: by Henry

Fairfield Osbor.n 41(»

History of the Aplodontia grou] > ; !>>■ W. P. Taylok 417

Some problems encountered in the study of fossil birds of tlie

west coast ; by L. H. Miller 417

Resolution of thanks 417

Excursions 417

XIV BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Page

I. On the relationship of the Eocene lemur NotJiarctus to the Adapidie
and to other primates 419

II. On the classification and pliylogeny of the Lemuroidea ; by William

K. Gregory 419

Problem of the Texas Tertiary sands ; by E. T. Dumble 447

A stratigi'aphie disturbance through the Ohio Valley, running from the
Appalachian Plateau, in Pennsylvania, to the Ozark Mountains, in Mis-
souri ; by James H. Gardner 477

Index 485

ILLUSTRATIONS
Plates

I'age

Plate 1— Adams : Portrait of Alfred E. Barlow 12

2— KuNZ : Portrait of Albert S. Bickmore 18

3— Clarke : Portrait of Horace C. Hovey 21

4 — Upham : Portrait of Newton Horace Winchell 27

" 5 — Fairch ild : Portrait of Joseph Le Conte 47

"6 " Le Conte memorial lodge, Yosemite Valley 48

" 7 — -Rich: Peculiarities of glacial erosion in central Illinois 72

" 8 — CusiiiNG : East and west walls of Brooklyn channel 205

" 9 — Branson : Red Beds of western Wyoming 217

" 10 — CuMiNGS and Galloway : Morphology of the Trepostomata .... 369

" 11 " " Morphology of the Trepostomata 370

" 12 " " Morphology of the Trepostomata 371

" 13 " " Morphology of the Trepostomata 372

" 14 " " Morphology of the Trepostomata 373

" 15 " " Morphology of the Trepostomata 374

16 — Washington and Day : Fumaroles in the Atrio del Cavallo 377

" 17 " " Cone of Etna from the near observatory

(south) 381

" 18 " " Interior of Etna crater from southeast. 382

" 19 " " Outer bocca of Etna from north 383

" 20 " " View of Vulcano from Lipari (north). 384

" 21 " " Crater of Vulcano 385

" 22 " " Salts at Vulcano 386

" 23 " " Large fumarole at Vulcano 387

" 24 " " Crater of Stromboli 388

" 25 — Dumble : Yegua formation and volcanic ash 460

" 26 " Corrigan sands and Fleming clays 464

" 27 " Contact of Jackson and Corrigan formations 467

Figures
Rich :

Figure 1 — Sketch map of Illinois 71

Crook :

Figure 1 — Talus produced by the retreat of the vertical cliff AG,

allowing for lateral weathering only 75

ILLUSTRATIONS XV

Gushing : Page

Figure 1^ — Portion of Cleveland quadrangle, showing location of

Brooklyn channel 207

2— Section of the Belt Line Railroad cut 207

Branson :

Figure 1 — Idealized section of gypsum beds 234

" 2 — Idealized section of gypsum beds 234

" 3 — Idealized section of gypsum beds drawn to scale 234

" 4 — Idealized section of gypsum beds drawn to scale 234

" 5 — Map showing hypothetical overflow basins of salt and

gypsum deposition during Salina time 239

Coleman :

Figure 1 — Cross-section of the Don beds 245

" 2 — Map showing interglacial beds in Ontario 250

" 3 — Sections of interglacial and postglacial valleys 253

Wright :

Figure 1 — Obsidian containing radial spherulites and bubble cavities 266
" 2 — Lythophysse, with fluted tongue of obsidian projecting

into hollow cavity, shown in center of photograph .... 266
" 3 — Tridymite crystals supported by needles of feldspar (?)

in recrystallized lithophysa 267

" 4— Radial lithophysa, in part recrystallized 268

" 5 — Sharply fluted tongue of black obsidian glass projecting

into lithophysal cavity 268

" 6 — Remarkable lithophysa^ in obsidian 269

" 7 — Lower wall of lithophysa on left side of figure G 270

" 8 — Enlarged central part of figure 7 271

" 9 — Diagrammatic representation of cube built up of six

pyramids ■ 272

" 10 — Ellipsoid-like lithophysal cavity, with central girdle of

crystallized material 272

" 11 — Etched surface of obsidian glass, moldavitic in character. 277

" 12 — Etched surface of a small obsidian fragment 278

Chadwick :

Figure 1 — Map showing location of Canton quadrangle and belts of

formations adjacent thereto 288

" 2 — Folded Paleozoic rocks on Ogdensburg and Canton quad-
rangles 289

" 3— Partial geologic map of Canton (quadrangle, showing re-
lation of Paleozoic rocks to pre-Cambrian belts 291

" 4 — Crumpling of Beekmantown limestone in old quarry at

Yaleville 292

" 5 — Inverted buckle crossing Raquette River below bridge at

Norfolk 292

" 6 — Actual cross-section of Potsdam beds one mile northwest

of Brick chapel, New York 293

" 7 — Cross-section of Potsdam outlier on Harrison Creek 293

«« 8 — Ideal cross-section of same valley before deformation

began 293

" 9 — Same valley after deformation ; dotted line shows present

erosional profile. 293

XVI BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

OSBOBN : Page

Figure 1 — Relations of the Jurassic and the Cretaceous in Wilt-
shire, England 298

MooK :

Figure 1 — -Diagrammatic representation of the thickness of the
Moi'risou formation in various areas from south to

north 316

" 2 — Diagrammatic representation of the thickness of the
Morrison formation in various areas from west to

east 317

" 3 — Diagrammatic representation of the thickness of the
Morrison formation in various areas from southwest

to northeast 318

" 4^-Diagrammatic representation of the probable relations of
the various parts of the Morrison formation with each

other before burial 321

Washington and Day:

Figure 1 — Sketch map of the crater of Stromboli 388

DUMBLE :

Figure 1 — Geologic map of eastern Texas 448

Gabdneb :

Figure 1 — Map showing extension of Chestnut Ridge disturbance.. 478

(27 plates; 41 figures.)

PUBLICATIONS

XVll

PUBLICATIONS OF THE GEOLOGICAL SOCIETY OF AMERICA

Regular Publications

The Society issues annually, in four quarterly parts, a single serial octavo
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Description of the Published Volumes

Volumes. Page.^!. Plates. Figures.

Vol. 1, 1889 ; 593 + xii 13 51

Vol. 2, 1890 622 -f xiv 23 63

Vol. 3, 1891 541 + xi 17 72

Vol. 4, 1892 458 + xi 10 55

Vol. 5, 1893 655 + xii 21 43

Vol. 6, 1894 528 + x 27 40

Vol. 7, 1895 558 + X 24 61

Vol. 8, 1896 446 + x 51 29

Vol. 9,1897 460 + x 29 49

Vol. 10, 1898 534 -f xii 54 83

Index to volumes 1-10 209

Vol.11, 1899 651 + xii 58 37

Vol. 12, 1900 538 + xii 45 28

Vol. 13, 1901 -.583 -f xii 58 47

Vol. 14, 1902 609 + xii 65 43

Vol. 15, 1903 6.36 + x 59 16

Vol. 16, 1904 636 + xii 94 74

Vol. 17, 1905 785 + xiv 84 96

Vol. 18. 1906 717 -f xii 74 59

Vol. 19, 1907 617 + X 41 31

Vol. 20, 1908 749 + xiv 111 35

Index to volumes 11-20 422

Vol. 21, 1909 823 + xvi 54 109

Vol. 22, 1910 747 + xii 31 66

Vol. 23, 1911 758 -f xvi 43 44

Vol. 24, 1912 737 + xviii 36 60

Vol. 25, 1913 802 + xviii 28 47

Vol. 26. 1914 5(»4 -f xxi 27 41

XVIU . BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Parts of Volume 26

Pagi-.s. Plates. Figures. P'"t'= ^o Price to

Fkm.ows. Public.

Number! 1-204 1-7 2 $2.60 $3.90

Nainl)er2 205-294 8-9 31 1.70 2.60

Number 3 2li5-3SS 10-24 6 1.90 2.75

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Rkprints fro.m A^olume 26

Reprints. Pages. PLAThs. Figures. Pk'Ce to Price to

Peli.ows. Public.

Proceedings of the Twenty-seventh
Auuual Meeting of the OTeolugical
Society of .America, held at I'hila-
delpliia, Fennsvivania, December
29, ;;0, and 31, 1914. E. O. Hovky,
Secretary 1-128 1-7 1-2 $1.60 |2 40

Proceedings of tlie Fifteenth Annual
3Jeeting of the Cordiileran Section
of the Geological Society of Amer-
ica, held at Seattle, Washington,
May 21 and 22, 1914. G. D. Lou-
HERBACK, Secretary 129-140 .... .... 20 30

Proceedings of the Sixth Annual
Meeting of the Paleontological So-
ciety, held at Piiiladelphia, Penn-
sylvania, December 29, 30, and 31,
1914. R. S. Bassler, (becretor?/ . . . 141-170 ... 35 55

Isostasy and radioactivity. G. F.

Becker ". 171-204 ... 45 65

Diastrophic importance of the uncon-
formitv at the base of the Berea grit
in Ohio. H. P. Cushi.ng "..205-216 8 1-2 20 30

Origin of the Red Beds of western

Wyoming. E. B. Bkansox 217-230 9 25 40

Origin of thick gypsum and salt de-
posits. E. B. Branson 231-242 1-5 20 .30

Length and character of the earliest
inler-Glacial period. A. P. Cole-
man 243-254 .... 1-3 20 30

Obsidian from Hrafntiniiuhryggur,
Iceland : its lithophysa? and sur-
face markings. F. E. \Vric;ht . . . 255-286 .... 1-12 60 90

Po.st-Ordovician deformation in the
Saint Lawrence Valley, New York,
(i. H. Chadwick ! 287-294 .' . 1-9 25 40

Close of Jurassic and opening of Cre-
taceous time in North America.
H. F. OsBORNf 295-302 .... 1 15 20

Reasons for regarding the Morrison
an introductorv Cretaceous forma-
tion. W. T. Lice t 303-314 20 30

Origin and distribution of the Morri-
son formation. C. C. MooKt 315-322 1-4 15 20

* Preliminary pages and index are distributed with number 4.

t Under the brochure heading is printed rEOCEEDiNGS of the Paleontologic;al Societt.

PUBLICATIONS XIX

Reprints. Pages. Plates. Figures. Priceto Price to

Fellows. Public.

Sauropoda and Stegosauria of the
Morrison of North America com-
pared with those of Europe and
eastern Africa. R. S. LuLLf 323-334 $0.20 $0.30

Paleobotanic evidence of the age of
tlie Morrison formation. E. \V.
Biouuvt 335-342 15 20

Invertebrate fauna of the Morrison

formation. T. W. Stanto.v t 343-348 10 15

Studies of the morphology and his-
tology of the Trepostomata or Mon-
ticuiiporoids. E. R. Cumings and
J. .1. (jALLOWAYt 349-374 10-15 50 75

Present condition of the volcanoes of
southern Italy. H. S. Washinx.-
TOx\ and A. L. Day 375-388 16-24 1 45 65

Proceedings of the Summer Meeting
of the Geological Society of Amer-
ica, held at the University of Cali-
fornia and at Stanford University,
August 3, 4, and 5, 1915. J. A.
Taff, Secretary pro f em 389-408 .... 25 40

Proceedings of the Summer Meeting
of the Paleontological Society, held
at the University of California and
at Stanford University, August 3, 4,
5, and 6, 1915. Chkster Stock, Sec-
retary pro tent 409-418 15 20

I. On the relationship of the Eocene
lemur Notharctas to the Adapidre
and to other jn-i mates. II. On the
classification and ))hylogeny of the
Lemuroidea. W. K. Gkegorv f. . . 419-446 35 55

Problem of the Texas Tertiary sands.

E. T. DfMBLE ■ 447-476 25-27 1 50 75

A stratigraphic disturbance through
the Oliio Valley, running from the
Appalachian plateau in Pennsylva-
nia to the Ozark Mountains in iNIis-
souri. .1. 11. ( fARDNEU 477-484 1 10 15

tUnder the brochure heading is printed Proceeding.s of the I'aleo.n'tglogical Society.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

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ai'e bibliographically distinct from the reprints issued by the Society.

The following separates of parts of volume 26 have been issued :

Regular Editions

Pages 141-170,

165 copies.

March

31,

1915

171-204,

33,

1915

205-216,

plate

140

June

15,

1915

217-230,

i t

190

28,

1915.

231-242,

190

i i

28,

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243-254,

28,

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255-286,

390

29,

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287-294,

140

30,

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295-302,*t

365

Angus'

17,

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303-31 4, *t

185

17,

1915

31 5-322, n

235

17,

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323-334,*t

485

((

17,

1915

335-342, n

235

17,

1915

343-348,*t

185

17,

1915

349-374, *^t plates

10-

-15,

465

((

17,

1915

375-388,

-24,

340

Septembei

1915

389-408,

Nov en

iber

22,

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409-418,*

165

1 1

22,

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4I9-446,*t

255

24,

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447-476,

1 i

-27,

December

1915

477-483,

110

1 1

1915

ecial Editions t

Pages 4-11,

40 (

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31,

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= 5-

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Page 75

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Pages 110-111,

540

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" 117-128,

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" 129-140,

31,

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* Bearing on the cover

Proceedixgs of the Paleoxtological Society.

[Reprinted from the Bulletin of the Geological Society of America, vol. , pp.

pis. , (Date)].

t Under the brochure heading is printed Proceedings of the Paleontological Society,
t Bearing imprint [From Bull. Geol. Soe. Am., Vol. 26, 1914].

CORRECTIONS AND INSERTIOjS'S XXI

CORRECTIONS AND INSERTIONS

All coutnlmtors to volume 20 have been invited to send correetions iind in
sertions to be made in their papers, and tlie volume has been scanned with
some care by the Editor. The following are such corrections and insertions as
are deemed worthy- of attention:

Page 209, line 4 from top ; for "Berea" read Bedford
232, line 17 from top ; for "18" read 36
232, line 18 from top ; for "127" read 137

236, line 21 from top ; for ".3" read .8+

237, line 7 from bottom ; for "75" read 225
247, line. IS from top ; omit line 18
253, line 2 from bottom ; omit line 2
253, line 1 from bottom: omit "BayV"

289, line 10 from bottom; for "heverlcyensis" read heverleyensc
292, line 1 from top: for "examples" rend example
294, line 11 from top; after "figure 9" innert before erosion

BULLETIN

OF THE

Geological Society of America

Volume 26 Number 1
MARCH, 1915

JOSEPH STANLEY. BROWN. EDITOR

PUBLISHED BY THE SOCIETY
MARCH, JUNE, SEPTEMBER, AND DECEMBER

CONTENTS

Pages
Proceedings of the Twenty-seventh Annual Meeting of the Geo-
logical Society of America, held at Philadelphia, Pennsylvania,
December 29, 30, and 3 1 , 1 9 1 4. E. O. Hovey, Secretary - 1-128

Proceedings of the Fifteenth Annual Meeting of the Cordilleran Sec-
tion of the Geological Society of America, held at Seattle,
Washington, May 21 and 22, 1914. G. D. Louderback,
Secretary 129-140

Proceedings of the Sixth Annual Meeting of the Paleontological So-
ciety, held at Philadelphia, Pennsylvania, December 29, 30,
and 31, 1914. R. S. Bassler, Secretary 141-170

Isostasy and Radioactivity. Presidential Address by George F.

Becker 171-204

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Subscription, $10 per year; with discount of 25 per cent to institutions and
libraries and to individuals residing elsewhere than in North America. Postage
to foreign countries in the postal union, forty (40) cents extra.

Communications should be addressed to The Geological Society of America,
care of 420 11th Street N. W., Washington, D. C, or 77th Street and Central
Park, West, New York City.

NOTICE. — In accordance with the rules established by Council, claims for
non-receipt of the preceding part of the Bulletin must be sent to the Secretary of
the Society within three months of the date of the receipt of this number in
order to be filled gratis.

Entered as second-class matter In the Post-Offlce at Washington, D. C,
under the Act of Congress of July 16, 1894

PRESS OF JUDD & DBTWEILEE^ INC., WASHINGTON, D. C.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA
Vol. 26, pp. 1-128, PLS. 1-7 March 31. 1915

I'KOCEEDIXGS OF TUK TWENTY-SEVENTH ANN UAL MEP]T-
l^G OF THE GEOLOGICAL SOCIETY OF A^FLEICA, HELD
AT PHILADELPHrA, PENNSYLVANIA, DECEMBER. 39, 30,
AND 31, 1911.

I^'DMrxi) Oris rioN'KY, Secrelari/

CONTENTS

Page

Se.s.sion of Tuesday. 1 )c'ct'niher L'i) 4

Report of the Council H

Secretary's repoi't 5

Treasurer's i-ei»ort 8

lOditors reimit 10

JOIectioii of .Vnditiii^ Coniuiittee 11

Election ol' oHicers 11

lOlectioii of Fellows 12

.Memoir of Alfred I'h-n(>st Harlow (witli iiililiou'raplix ) : liy Frank I >.

.Vdams 12

Memoir of Albert S. Biclimore ; by (Jeorj^e F. Kuuz IS

Memoir of Horace C. Hovey (with biblioj^raphy ) ; l)y .John ]M. Clarke. 21
.Memoir of Newton Horace Wincliell (with biltliotrraphy ) : by Wai'ren

Upliam 27

Memoir of .Tosepli Le Conte (witli biblioj^raphy) ; ity Herman L. Fair

diild 47

Report of ( 'ommittee on I'lmto.uiaiihs .17

Ke|»ort of Committe<' on ( Icolo.u'ical Xonieiiciatni-c Ttl

'j'itles and abstracts of pajiers iiresentcil in ucncral session ami dis-
cussions therenii ."•S

Relation of bacteria to dejiosition of caicinni carbonate [ab-
stract j : by Karl F. Kellermau oS

Coral reefs and reef coi'als of the snntbeasteni riiiled States,
their j,'eolo;,'ic history and sii,'nilicance | abstract and discus-
sion | ; by Tliomas AVayland Nauf^han •">>>

Causes producing scratcluMJ. impressed, fi'actiu'cd. and i-eccnicidcd
pebbles in ancient cciu^rlcinicraf cs [abstract and discussion |: b,\

.Tohn M. Clarke <>0

Titles and abstrjicts of papers jtrcsenled before tlie First Section and

discussions thereon 01

()ri;;in nf the lied Reds of western W.\onnni: |absti-act and dis-

<'Ussion I : by E. R. Rranson t»l

.New iioints on the ori;;iu of dolonnles |abslract[; b.\ Francis M.

\an Tu.\l «■-

I — Bull. Gkol. Soc. A.m., v..i,. 'jr., i-.M 1 (1)

PROCEEDINGS OE THE I'JI 1 L.\l)i;i,I'lI l.\ MEETING

Page
Kinit,'(' ;iii(l rhythmic action of saiul-hlast i-rosioii, from studies in

the I^ibyan Desert [abstract] : by William H. Hobbs (>.'>

Corrasivc ofticioncy of natui'al san(I-l)last | abstract | : liy Charles
Kcyps (j:;

False faull-scar]»s of desert ran.t;es [abstract] : by Charles Keyes. 05

Sti-atij,'raiihic disturbance tlirougli the (»liin \'alley runuinfi from
tlie Ai»])alachian I'latean in IVnnsylvania to the Ozark Moun-
tains in Missouri jabstract]; by James II. (iardner (Kl

I'reliminary paper on recent crustal movements in the Lake Erie
region [abstract and discussion]; by Charles E. Decker 06

Quaternary deformation in southern Illinois and southeastern Mis-
souri [abstract] ; by Eugene Wesley Shaw (!7

( >1(1 shorelines of Mackinac Island and their relations to the lake
history [abstract] ; by Frank B. Taylor Os

Some peculiarities of glacial erosion near the margin of the conti-
nental glacier in central Illinois [abstract and discussion]; by
John L. Rich TO

X(>\v evidence of the existence of fixed anticyclones above conti-
nental glaciers [abstract] ; by William Herbert IIol>bs 7';

Origin of Monks mound [abstract] ; by A. R. Crook 74

Can C-shaped valleys bo produced by I'emovai of talusV [ab-
stracl I ; by Alfred C. Lane 75

rhysiographic studies in the driftless art* jabstract] ; by Arthur
C. Trowbridge T<;

Ilemicones at the mouths of hanging valleys [abstract] ; by
Charles E. 1 )ecker 70

Rlock diagrams of state physiography [abstract] ; by A. K. Lobeck 77

Kilauea. a drop-fault crater [abstract] ; by George Carroll Curtis 77

Age !is the determinant of character in volcanoes ]al)stract]; liy
George Carroll Curtis 7S.

Comprehensive coral island theory [abstract] ; by George Carroll
Cui'tis 7.";

Evidence of continental glaciation on Mount Katahdin [abstract] ;
by Geoi'gc Carroll Curtis 7n

Naturalistic land model, the "last word in geology"' [abstract] ;

by George ( 'arroU Curtis 7!*

Second Section 81

Titles and abstracts of pajiers presented before the Third Section and
discussions thereon 81

Pre-Cambrian igneous rocks of the Pennsylvania Piedmont [ab-
stract] ; by F. Bascom 81

Magraatie assimilation [abstract] ; by F. Bascom 82

Hypersthene syenite (akerite) of the middle and northern Blue
Ridge region, Virginia [itbstract] ; by Thomas L. AVatson and
Justus H. Cline 82

Pyrrhotite, norite, and pyroxenite from Litchfield, Connecticut
[abstract] ; by Ernest Howe 83

Some effects of pressure on rocks and nnnerals [abstract and dis-
cussion] ; by John Johnstou 83

("OX TEXTS 8

Page
Primary chalcocite in tlie fluur.spar veins of Jefferson Comity,

Colorado [abstract] ; by Horace B. Patton 84

Recent remarkable gold "strike" at the Cresson INIine. Cripiile

Creek, Colorado [abstract and discussion] : by Horace P>. Patton S4
I'latinum-gold lode deposit in southern Nevada [abstract] : by

Adolph Knopf 85

Organic origin of some mineral deposits in unaltered Paleozoic

sediments [abstract and discussion]; by Gilbert van Ingen.... 85
Isostasy and radioactivity; Presidential address by George F.

Beclver S(i

Session of Wednesday. I )ecember 30 87

Report of Auditing Committee 87

Titles and abstracts of papers presented in general session and dis-
cussions tliereon 87

Revision of pre-Cambrian classification in Ontario [alistract and

discussion] ; by Willet G. Miller and Cyril W. Knight 87

North American continent in Upper Devonic time [abstract and

discussion] ; by Amadeus W. Grabau 88

Symposium on the passage from the Jurassic to the ('retaccons '.)()

Titles and abstracts of papers presented before the First Section and

discussions thereon !<()

Type of rifted relict mountain, or rift mountain |ai>strMcl and dis-
cussion 1 ; by John M. Clarke no

lOvidence of recent subsidence on the coast of Maine | abstract and

discussion] ; by Charles A. Davis !)1

Basic rocks of Rhode Island: their correlation and relationshi]>s

[abstract and discussion] ; by A. C. Hawkins and C. AV. P.rov>n. 9i'
Acadian Triassic [abstract and discussion] ; by Sidney Powers... t>:;
(Jeological hi.story of the Bay of Fundy [al)stract] ; liy Sidney

I 'owers 04

Tides and al)stracts of papers presented before the Second Section. . . 05
Alexandrian rocks of northeastern Illinois and eastern Wiscon-
sin [abstract] ; by T. E. Savage 95

Olentangy shale and associated deposits of northern oliio |ab-

stract] ; by (Minton P. Stauffer 05

Diastrophic importance of the unconformity at tlu' base of the

Berea sandstone in Ohio [abstract 1: by H. P. Cushing 90

Kinderhookian age of the Chattanoogan series [abstract] : by

K. <). TTlrich 9.;

'I'itles and abstracts of jiajiers i)resente(l before the Third Section and

di.scussions thereon 99

()rigin of the iron ores ;it Kinnia. Sweden labstractj; by Regi-
nald it. Oaly 90

(digin of the iiocky Moinitain iiliosphate deposits iabstract]; by

Kliot P.lMckwelder 190

Regional alteration of oil shales |,Mbstract|: by l»a\id White 101

()il pools of southern ( >Ul;iboin;i and Tiortbein 'i"e.\as (absti'actl:

by James II. (Jardiier 19L'

Natural gas at Cleveland, <»liio |abs|racl | : by Kraiik K. \':in Horn KVJ

4 ritUCKEDlNGW OF THE I'HILADKLI'II I A MEETING

I 'age
Origin of fliick s;ilt jiih] .i,'yiisuiii deposits [absti'iict and discus-
sion I ; l)y 10. I'. I'lanson Mr.',

('rystallino uiarlilcs of Alabama [ahstract | : hy William V. I'routy 104

Annual dinner KM

Session of Thursday, Decemhor '.'A l()r»

Titles and alisti'acts of jiajiers presented in general session and <lis-

cussions thereon lOil

Present condition of the volcanoes of southern Italy [abstract] ;

by H. S. Washington and A. L. Day 105

Recent eruptions of J^assen I'eak. California [abstract] ; by J. S.

Diller Km

Physiographic study of the Cretaceous-Eocene period in the Hocky
Mountain front and Great Plains provinces [abstract] : by

George H. Ashley 105

Relation of physiographic changes of ore alterations [abstract] ;

by Wallace W. Atwood lOU

Graphic projection of Pleistocene climatic oscillations i abstract] ;

by Chester A. Reed.s lOG

Geologic deposits in relation to Pleistocene man [abstract] ; by

Chester A. Reeds ]0!t

Physiographic features of western Kuroi)e as a factor in tlie \vai-

[abstract] ; by I)<mglas W. Johnson 110

Vote of thanks 110

John Boyd Thacher Park: The Helderberg Escarpment as a geo-
logical park [abstract] ; by George F. Kunz 110

Relief of our Pacific coast [abstract] : by J. S. Diller Ill

Titles and abstracts of papers presented before the Second Section. . . llii
Devonian of central Missouri [abstract] : by E. B. Branson and

D. K. Greger 112

Olentangy shale of central Ohio and its stratigraphic si.sni flea i ice

[abstract] : by Amadeus AV. Graban Hi:

Hamilton .group of western X(>w York [abstract]; by Amadeus

W. (Jrabau 11:;

Extension of Morrison formation into New Mexico [abstract i : by

N. H. Darton 11;',

Geological reconnaissance of I'orto Rico [abstract] ; by Charles P.

Berkey Ho

Relation of Cretaceous formations to the Rocky Mountains in

Colorado and New Mexico [abstract] : by Willis T. Lee Ill

Post-Ordovician deformation in the Saint liawrence Valley. New

York [abstract] ; by George H. Chadwick 115

Officers, Correspondents, and Fellows of the Geological Society of America. 117

Session op Tuesday, December 39

Tlie lirsi general session ol' Hie Sneieiy was called to order at 9.55
o'clock a. 111., 'I'uesday, l)eceml)er ;.'!), in the lecture luill ul' the Academy

HEPOKT OF TIIK COUNCIL 5

of Natural Sciences, Philadelphia, Pennsylvania, by First Vice-President
Lindgren in the absence of Pi-esident Becker, who was detained at home
by illness. Professor Lindgren introdnced Dr. Samuel G. Dixon, who
in turn welcomed the visiting geologists and paleontologists in the name
of the Academy.

The report of the Couiuil for the year ending November 30, 1914, was
])resented as follows :

REPORT OP THE COUNCIL

To the Geological tSocietij of Aiiier'ua, in lii'i'idij-secenlh annual meeting
assembled:

The regular aiuiuai meeting of the Council was held at Princeton,
New Jersey, in eonnection with the meeting of the Society, December ;;(»
and 31, 1913, and January 1, 1914.

The details of administration for the twenty-sixth year of the existence
of the Society are given in the following reports of the officers :

Secretary's Report

To the Council of the Geological Society of America:

Meetings. — ^The proceedings of the annual general meeting of the
Society held at Princeton, N. J., December 30 and 31, 1913, and Janu-
ary 1, 1914, have been recorded in volume 25, pages 1-118; of the Cor-
dilleran Section, pages 119-126, and of the Paleontological Society, pages
127-156, of the Bulletin.

Membership. — During the past year the Society has lost four Fellows^
by death — Alfred E. Barlow, Albert S. Bickmore, Horace C. Hovey, and
Newton H. Winciiell; and three Correspondents, JI. Kosenbusch, Eduard
Suess, and Th. Tschernyschew. One resignation has become effective.
The names of the twelve Fellows elected at the Princeton meeting have
been added to the list, all of them having completed their membership
according to the rule. The present enrollment of the Society is 363.
Nineteen candidates for Fellowship are before the Society for election
and several applications are under consideration by the Council.

Distribution of Bulletin. — There have been received during the year
8 new sub.scriptions to tlif ihdlft in, and 5 subscri]>t ions bave been dis-
continued, makini^- tlir nnndicr nf sidtsciilici's IIS.

The irreguiai- disli-ihul ion (if llic liullclin diii'ing tlie past year has
been as follows: Compiek' Mdunics sold Id I he |)nblic, 46; sold to Fel-

' .since the meeting the SecTotary has receiviil imiicf of the death of .\rlhiir W. \\\\-
inott on May 8, 1914.

i'KocKKDlNOS Ol' THE I'JI IL.VDELriilA MEETING

low.s, 1; sent out to .supply deficiencies, 1, and delinquent.^:, 7; brochures
sent out to supply deficiencies, 5, and delinquents, 67; sold to Fellows,
14 ; sold to the public, 53.

Bulletin sales. — The receipts from subscriptions to and .sales of the
Bulletin during the past year are shown in the following table:

Bulletin Receipts, December 1, 1913-Noveinher 30, 1914

Complete volumes.

Brochure.s.

Grand

Kellows.

Public.

Total.

Fellows.

Public.

Total.

total.

Volume 1 . . . .

$7.50

7.50

7 50

7.50

15.00

7.50

15.00

7.50

15.00

30.00

15.00

22.50

68.50

S21.00

30.00

$7.50

7.50

7 50

15.00

7.50

15.00

7.50

15.00

30.00

15.00

22.50

76.00

S21.00

30.00

$7.50

Volume 2

$0.40

7.90

V^olume ?i

7.50

Volume 4 . . . .

7.50

Volume 5

.20
.65

7.70

Volume 6

8.15

Volume 7

7.50

Volume 8...
Volume 9 ...

"$6.76"
.80
.60

.30
"'3!46'

.30

.70

4.20

.60

7.80
8.20

Volume 10

11.70

Volume 11

15.60

Volume 12

7.50

Volume 13....
Volume 14 ... .
Volume 15 ... .

'"""io'
"'a'q

1.50

2.70

.30

.90

'".'55"

1.85
2.70
.40
.90
.40
.55

9.35
10.20
15.40

Volume 16....
Volume 17. . . .

15.90
7.90

Volume 18

8.05

Volume 19

15.00

Volume 20....
Volume 21

1.20

31.20
30.00

Volume 22....
Volume 23

8.35
2.00
6.35

.90

5.00

20.33

.25

9.25

7.00

26.68

.25

24.25
29.50

Volume 24. . . .
A'olume 25 . .

$7.50

102.68

S21.25

Vnliiinp '■'H

30.00

Total . . .
Index; 1-10

$7.50

$1,198.50

6.75

17.50

$1,206.00

6.75

17.50

$19.65

$38.58

$58.23

$1,264.23
6.75

Index 11 -'>0

17.50

Total . .

$7.50

81,222.75

$1,230.25

$19.65

$38.58

$58 . 23

$1,288.48

Receipts for the fiscal .v(
Previously reported

$1,288.48
17.012.41

Total receipts to date .$1,8.300.89

Charged, but not yet received: On 1911 account 7.50

On 1912 account 9.40

On 1914 account 89.35

Total sales to date $18,407.14

REPORT OF Till': forXCTT, 7

One subscription to vohime 25 is still to be paid for and 6 of the
resrular subscribers have not vet sent in their orders for the volume. Xo
volumes are sent out now except on definite orders.

Expenses. — The following table gives the cost of administration and
of Bulletin distribution during the past year:

EXPENDITURE OF SECRETARY'S OFFICE DURING THE FISCAL YEAR ENDING NOVEMBER

30, 1914

Arrnunt of Adminif>tr(ttion

Postage .$72.10

I'o.st-cards 1" • 40

Printing (including annual meetings «if litl,'! and 1914) 85.00

Labor at sundry times 6 . 24

Typewriter 7290

Typewriter i-ibbons 1 . .')()

Messeng«M' service -75

Telephone cliarges 1 . 30

Telegrams .85

Express 4 . 57

Expenses of trip to Philadelphia to arrange for annual

meettng . . 6 . 33

Collection charges on checks .20

.\ddressograph plates .04

Letter-heads, envelopes, etcetera 50.25

Rinding three copies of Bulletin 6.40

C^ordilleran Section ( 1914 » 40. 05

Total $365.96

Account of BiiUetin

Po»tage $20.01

Express 28.84

Telegrams 82

Wrapping paper ? 3 . 87

Messenger .service 1 . 90

Labor at sundry times 9 .00

Rubl>er .stamp .40

Jurat .,50

Collection charges on cliecks 1.25

Bulletin envelopes 34.30

Puichase of liack numbers of liulletin 18.00

Total $118.89

Total expcndihiifs I'or llic year $484.85

Respectfully submitted, Edmund Otis IIovey,

Secretary.

8 PROCEEDINGS OF THE PHILADELPHIA MEETING

Treasurer's Report

To the Council of the Geological Society of America:

The Treasurer herewith submits his annual report for the year endinfj
Xovember 30, 1914.

One Fellow — Robert T. Hill — taking advantage of the new provision
of the By-laws, has commuted for life during the year by the payment
of one hundred dollars, thus increasing the total Life Commutations,
since the organization of the Society, to 104, which, with the 4 Honorary
Life Members, makes a total of 108. One Life Member died during the
year, which, with tlie 14 previous deaths, leaves 93 living Life Members.

The membership of the Society at tlie present time is 363, of whom
270 pay annual dues. Twelve new members were elected at the last
annual meeting, all of whom qualified. Tliere liave been 4 deaths during
the year and 1 resignation. Fifteen members are delinquent in the pay-
ment of dues — 1 for five years, 3 for three years, and are therefore liable
to be dropped from the roll — and 11 for one year.

With the advice of the Investment Committee, the Treasurer bought
during the year two Southern Bell Telephone and Telegraph Company
five per cent bonds, with interest, at a cost of $2,008.88.

RECEIPTS

Balance in treasury December 1. 1913 $1,029.05

Fellowship fees. 1910 (1) .$10.00

1911 (1) 10.00

1912 (3) 30.00

1913 (10) 100.00

1914 (256) 2,560. 00

1915 (1) 10.00

1 for 9 years in advance 90.00

2.810.00

Initiation fees (12) *. 120.00

Life commutation ( 1 1 100 . 00

Interest on investments :

Iowa Apartment House stock ,50.00

Ontario Apartment House stock 200 . 00

Texas and Pacific Railroad Company

bonds 100.00

U. S. Steel Corporation ImukIs 150. UO

St. Louis, Iron Moimtalii :\\u\ Soutlieni

Railway Company Itond 50. (M)

St. Louis and San Francisco Railroad

Company equipment bond 50.00

Fairmont and Clarksburg Traction Com-
pany bonds 100 . 00

REPORT OF THE COUNCIL

Consolidation Coal Company bonds 100.00

Chicago Railways Company bond 100.00

Soutliern Bell Telephone and Telegraph

(\mipany bonds .''»0.00

Inrerest on dei>osits. lialtimoiv Trust

Company 70 . 74

1,020.74

(!la.se Library, accessions 191?> 150.00

Collection charge added to checks .50

Uefniid for overcharge 9 . 50

Received from Secretary :

Sales of publications .^1,288. 48

Authors' separates 22 . 20

Collection charges added to checks .4Pi

Paleontological Society's share of i»rinting 10.00

Rinding Bulletin 1.60

— 1,322.74

$6,563.13

EXPENDITURES

Secretary's office :

Administration . $365 .96

Bulletin 118. 89

Allowance 700.00

$1,184 . 85

Treasurer's office :

Postage, bond, safe-deposit box $53.75

Allowance for clerical hire 50.00

103 . 75

Publication of Bulletin :

Printing - $1,617.70

Engraving 342.67

Editor's allowance 250.00

2,210.37

Purchase of two Southern Bell Teleplione and Telegraph

tive per cent bonds, with interest 2,008.88

5,507.85

Balance in Baltimore Trust Company December 1, 1914 1,055.28

$6,563 . V
Respectfully .suljiuitted,

Wm. BubbUCK Cb.AHK,

Trt'dsurt'i'.

2 This Ucm incbirtes transportatinn chargps on the regular distribution of th<'

Liulletln r-'-'i-i-

and the following charges which have been refunded by the authors :

Authors" separates in e.xcess of number given gratis by the Society 2'2.'20

I'ROCEEDINGS OF THE PHILADELPHIA MEETING

Editor's Report

7'o ilie Council of the Geological Society of America:

The Editor submits herewith liis annual report. The followino- lalilc
eover statistical data for the twentv-five volumes thus far issued :

Cost.

Average —
Vols. 1-20.

Vol. 21.

Vol. 22.

Vol. 23.

Vol. 24.

Vol. 25.

pp. 610.
p s. 55.

pp. 839.
pis. 54.

pp. 759.
ps. 31.

pp. 774.

p s. 43.

pp. 756.
p s. 36.

p 1. 820.
p s. 28.

r.etter press. .
Illustrations. .

$1,686.58
390.99

$2,049.95
404.27

$1,660.45
260.81

$1,750.40
274.70

$1,647.90
288.80

$2,049.19
342.67

$2,077.57

$2,454.22

$1,921.26

$2,025.10

$1,936.70

$2,391.86

A verage
per page . .

$3.41

$2.93

$2.53

$2.62

$2.56

$2.91

Classification.

>-,

1
Q

fee

fcti

§i

o^.

»j

Volume.

tc-2
o o

O O

«- o
2 tc

-t^ c

■s.

'0
56
O

2
o
E

■A
'«

Total.

fumbt

jr of I

)ages.

116

137

593+xii

110

111

168

662+xiv

158

104

541+xii

1?4

458+xii

138

135

107

665+xii

111

538+x

105

123

558+x

• > • •

446+ X

102

138

< ■ ■ *

460+ X

534-f-xiii

110

188

651 + xii

199

5 1

■ • > •

538+xi

125

116

165

583+xii

183

118

609+xi

26
64

124
HI

3
78

94
30

36
102

267
141

77
67

17
22

636 +x

636+xiii

161

294

785+xiv

164

141

246

717+iii

100

108

155

1 56

617+x

303

132

749 + xiv

234

106

111

8234-xvi

403

747 -(-xii

126

108

145

134

758+xvi

160

106

23 i

133

737+xviii

211

156

175

108

802-l-xviii

REPORT OF THE rOlNclT, 11

Eespectfully submitted, Joseph Stanley-Brown,

Editor.

Eespectfully submitted. The Council.

Pcremher 29, 1914.

On motion, tbe report was laid on tbe table as usual until tbe following
day.

election of vrDTTIXO COMMITTFF

The Auditing Committee, consisting of H. L. Faircbild, J. jVI. Clarke,
and E. B. Mathews, was then elected, and the Treasurer's report was
referred to it for examination.

ELECTION OF OFFICERS

The Secretary declared the vote for officers for 191--) as follows, the
Ijallots having been canvassed and counted by the Council in accordance
with the By-Laws :

President :

Arthur P. Cole.man. Toronto, Canada.

First Vice-President :
L. V. Piiissox. Xew Haven, Conn.

Second Vice-President :
11. 1'. CusHiNG. Cleveland, Ohio.

Th ird Vice-President:
E. (). ri.itic'ii. Washington, D. C.

Secretary:
Edmuxd OtisHovey, N"ew York City.

Treasurer:
William Jiii.i.ocK Clahk, Baltimore, Md.

Editor:
JosKiMi Stanli:v-Bh()WN, New ^'()^k City.

Ldintnaii :
Fi.'WK V\. \'\\ lloKX. CIcM'land, Oliio.

Coundtors:
Chai!Li:s |\. ij;nii. Mndisdiu Wis.
Thomas L. W.vtsox, Cliarlottesville, \'a.

12 PROCEEDINGS OF THE PHILADELPHIA MEETING

ELECTION OF FELLOWS

Tlie Secretary announced the election in due form of the following-
Fellows, the ballots having been canvassed and counted by the Council:

Jon.x Andrew x\llex, B. A., M. Sc, Ph. I)., University of Alberta, Strathcona,

Canada.
Joseph Austen Bancroft, B. A., M. A., Ph. D., McGill Univer.slty, Montreal,

Canada.
Frank Catikakt Calkins, B. S., U. S. (Geological Survey, Washington, D. C.
Charles Camsell. B. A.. Geological Survey of Canada, Ottawa. Canada.
Charles H. Clapp, S. P... Ph. I)., University of Arizona, Tucson. Arizona.
Wn.LiAM Frank Eugene (Keed) Ouhlev. T^niversity of Chicago, Chicago,

Illinois.
Rav Vernon Hennen, A. P.., P.. S.. C. E.. West Virginia (Jeoiogical Survey,

Morgautown. West Virgiiii;i.
Roy Jay Holden. B. S., Virginia Polytechnic Institute, Blac-ksburg, Virginia.
George Daviu Hvurakd, B. S., M. S.. A. M.. I'h. D., Oberlin College, Oberlin.

Ohio.
Walter Fred Hunt, A. B., A. M., University of Michigan, Ann Arbor, Michigan.
Edward Charles Jeffrey, A. B., Ph. D., Harvard Univer.sity, Cambridge, Mass.
Esper Signius Larsen, Jr., B. S., U. S. Geological Survey, Washington, D. C.
James H. Lees, B. A., M. S., Iowa Geological Survey, Des Moines, Iowa.
Francois Emile Matthes, B. S., U. S. Geological Survey, Washington, I). C.
Thomas Poole Maynard, A. B., Ph. D., Chattanooga, Tenn.
Herbert E. Merwin, S. B., Ph. r>.. Geophysical Laboratory, Washington, D. C.
Alexander Hamilton Phillips, B. S., D. Sc, Princeton University, Princeton,

N. J.
Millard King Shaler, A. B., B. S.. United States Embas.sy, London, England.
Stephen Taber, A. B., Ph. D., University of South Carolina, Columbia, S. C.

AinKiuiiciMiient \\as then made by the Secretary that the Society had
lost four Fellows by death during the year 1914: Alfred E. Barlow,
Albert S. Bickmore, Horace C. Hovey, and Newton H. Winchell, and
three Correspondents: H. Eosenbusch, Eduard Suess, and Th. Tscherny-
schew. Memorials of deceased Fellows were presented as follows:

MEMOIR OF ALFRED ERNEST BARLOW
BY frank D. ADAMS

T'he news of tbe loss of the Empress of Ireland, which brought such
\vi(l('.s|)i'ea(l sorrow to so many liomes, not only in the Dominion of Canada,
bill also ill tbe ITnited States, came with a sense of personal bereavement
to many members of the Geological Society of America wlien it was
learned that Dr. Alfred E. Barlow was among those who had perished.
Having attended the closing meeting of the Eoyal Society of Canada,

BULL. GEOL. SOC. AM.

VOL. 26, 1914, PL. 1

(W^ lJu/(Uuu^

MEMOIR OF A. E. BARLOW 13

which was held in jMontreal, Doctor Barlow, on the morning of May 28,
left with Mrs. Barlow for Qucl^ec, where he took passage for Liverpool,
intending to spend some months in England; hut that night, when near
Father Point, in the Gulf of Saint Lawrence, the Empress of Ireland
was struck hy the collier Slorstadt, coming from Sydney, Nova Scotia, to
^[(mtreal, heavily laden w ilh coal, and in a few minutes sank with most
of her passengers and crew. Doctor BarloAV, who was very alert, active,
and a powerful swinnner, evidently swam away from the sinking vessel
supporting liis wife. l)ut was struck l)y a piece of wreckage, rendered
imconscious, and both succumbed.

Alfred E. Barlow was born in Montreal on June 17, 1861, and was a
younger son of liobert Barlow of the Eoyal Engineers, who in earlier life
was engaged on the Ordnance Survey of England, but subsequently came
to Canada, and was appointed by Sir William Logan to the position of
Chief Draughtsman on the Geological Sun^ey of Canada, Avhich position
he filled for many years, his work leading up finally to the publication
of the great Geological Map ol' the Dominion of Canada, issued by Tjogan
in 186.'), wliieli was (Hie of the liiicst examples of cartogra^jhy which had
appeared up to that time.

Alfred Barlow, having coiu])Ieted Ids schooling in Montreal, entered
the Faculty of Arts of ]\[cGill University in 18T9, Mhere he studied
geology under Sir AVilliam Dawson, graduating four years later with
lirst-rank honors in natural science and the Logan gold medal. Shortly
after graduating he was appointed to a position on the statf of the
Geological Survey of Canada, and for two summers worked under the
late Dr. 17. W. Ells in the Shickshock Mountains of the Gaspe District
and in tlie Cobequid Mountains of N"ova Scotia. In 1885 he became
assistant to Dr. A. C. Law^son, and for several seasons worked with him
in the Lake of the Woods and Eainy Lake region. This epoch-making
investigation awakened in him a keen interest in the problems presented
by the ancient crystalline rocks of Canada, to the study of wliich in their
various phases he devoted the remainder of his life.

From 1887 to 1895 he was engaged in a study of the pre-Cambrian
rocks of the Sudbury, Nipissing, and Timiskaming districts, in eastern
Ontario. The results of this work appear in several reports issued by
the Geological Survey of Canada. In these he pointed out the promising
cliaracter of this region as a field for careful prospecting, which is of
interest, since some years later the rich silver veins of the Cobalt Camp
were discovered in this area. During this time he also made a detailed
report on tlie geologv of llie niekel-l)eariiig rocks of the township of
Creigliton, in the Sndlniiv |)isiii((. for (lie Moml Niekfl Coninauy, ami

14 PROCEEDINGS OF THE PHILADELPHIA MEETING .

the accuracy of certain of his deductions lias recently hecn proved in the
discovery of large bodies of very valuable nickel ores in the township of
Levack by explorations whiih were carried out by the company at points
indicated by Doctor P)arl(»w. This work on tlie co})])er-nickel ores of the
.Sudbury region was continued for the (Jeological Survey of Canada, and
it is not too much to say that his report on the nickel and copper deposits
of Sudbury has now l)ecome a classic in the literature of ore deposits.
It was Doctor Barlow who first established the claim of these remarkable
ore bodies to be considered as of magmatic origin. About this time the
writer was requested bv Dr. (ieorge M. Dawson, tlien Director of the
Geological Survey of Canada, to undertake the mapping and detailed
study of a large area of the Grenville Series in the Haliburton and Ban-
croft districts of eastern Ontario, and as the work developed Doctor
Barlow was associated with him. This region was geologically an abso-
lutely virgin field, but it had an area of 4,"i00 square miles, and it Avas
necessary to make a topographical survey to secure a map on which the
ucolo^ical sti'uctiires of the resriou could be shown. Doctor Barlow's
ability as an cxccllciil io|togra])her. as well as a kccJi geologist, and his
indefatigable energy contributed largely to the successful completion of
this work, the i-esult of which a])i)e;i red in the (Jeology of the Haliburton
and Bancroft Areas, jiuMished by the Geological Survey in 1910. Among
the results obtained from the study of this region was the discovery of
great bodies of nepheline syenite occurring about the border of the in-
truding granite l)atholiths and presenting manv i'<Mnarkable variations in
composition, some \arieties being rich in coiunduni, which were subse-
quently made the basis of an extensive industry for the exploitation of
the mineral.

Doctor Barlow served on several im[)or;ant c()nnnissions. One of these
was that ai)pointinent by the Dominion government in 1905 to report on
the zinc resources of British Columbia. Another was the commission
appointed by t!u' government of the Province of Quebec in 1910 to report
on the resourc-es of the Chibougamau District in that province. This is
situated in northern Quebec, on the eastern prolongation of the great belt
of pre-Cambrian rocks on which farther west the great mining camps
of Cobalt, Porcupine, and Sudbury are found. IJeports of the mineral
richness of this region had been brought in by various explorers and the
government Avas being urged to vote a large sum for the construction of
a railroad into this remote region for the purpose of making these sup-
posed mineral deposits accessible. The commission, with Doctor Barlow
as chairman, after maldng a thorough study of the region, reported
against tlie construction of the railrond. Ibns nol only presenting a large

MEMOIR OF A. E. BARLOW 15

and useless expenditure of public money, but also much rash speculation
in private funds which would undoubtedly have followed.

In 1907 he severed his connection with the Geological Survey of Can-
ada to engage in private practice as a mining geologist and took up his
residence in Montreal.

Doctor Barlow was for many years on the Council of the Canadian
Mining Institute, and in 1913 was elected president of the institute,
which position he held for two years. He was elected a Fellow of the
Geological Society of America in 1906 and a Fellow of the Royal Society
of Canada in 1903. He was a member of the Executive Committee of
the Twelfth International Geological Congress, which met in Canada in
the summer of 1913, and devoted much time to the work of this important
gathering. He received the degree of Doctor of Science from McGill
University in 1900, and was a lecturer in geology at this university at
the time of his demise.

In 1887 he married Frances Elizabeth Toms, of Ottawa, and they
leave one son. Doctor Barlow was a man of marked ability, great energy,
and abounding enthusiasm — a pleasant companion and a warm frienrl.
His loss will long be felt by tlic geologists of Canada.

BIBLIOGRAPHY

1882-84. List of fossils collected by A. E. Barlow at Grand Greve and Gaspe.

Geol. Surv. of Canada, Report of Progress, 1882-84, p. 24P:.
1890-91. Notes on Ontario nickel and copper industries. Geol. Surv. of Can-
ada, Ann. Kept., \ol. v, pp. 11.5-118ss.
On the nickel and copper deposits of Sudbury, Ontario, (icol. Surv,
of Canada, Ann. Kept., vol. v, pp. 122-143s.
1891. On the nickel and copper deposits of Sudbury, Ontario. Ottawa Nat-
uralist, vol. V, pp. 51-71.
181)2. On the relation of the Laurentian and Huronian on the north side of
Lalve Huron. Am. Journ. Sci., 3d series, vol. xliv, pp. 280-239.
Summary report on the area including Lake Nipissing and the southern
portions of lakes Temagami, Timiscaming, and Keepawa. Geol. Surv.
of Canada, Ann. Rept., vol. vi, pp. 34-35A.

1893. Relations of the Laurentian and Huronian rocks to the north of I-akc

Huron. Bull. Geol. Soc. Am., vol. 4, pp. .31.3-.'!.'!2.
Summary report on surveys in the Temagami District, Ontario. Geol.
Surv. of Canada, Ann. Rept., vol. vi, pj). 30-33AA.

1894. Summary report on surveys in the Temagami District. Ontario. Geol.

Surv. of Canada, Ann. Ropt., vol. vii, pp. ."'>G-.57A.

1895. On some dikes containing "huronite." Ottawa Naturalist, vol. Ix. pp.

25-47.
Notes on certain rocks from the L.-ilirador T(>ninsula. (.'i^nl. ."^iiiv. of

Canada, Ann. Rept, vol. viii. ii. 20T and pp. :;r>0-:!.'')lL.
II — BuLu Gnofi. Soc. Am., Vol. 2i\, I'.MJ

16 PROCEEDINGS OF THE PHILADELPHIA MEETING

Summary report on surveys in the Temagami District, Ontario. Geol.
Surv. of Canada, Ann. Rept., vol. viii, pp. 61-63A.

The pliysical features and geology of the route of the proposed Ottawa
Canal between the Saint I/awrence River and Lalie Huron, by R. W.
Ells and A. E. Barlow. Trans. Roy. Soc. Canada, 2d ser., vol. i, sec.
iv, pp. 16.3-100.
1S96. Summary report on a geological survey of the Haliburton District, On-
tario, by F. D. Adams and A. E. Barlow. Geol. Surv. of Canada,
Ann. Rept., vol. ix, pp. 45-53A.
1897. On tlie occurrence of cancrinite in Canada. Can. Record of Science,
v<tl. vii, p. 22.

On the relations and structure of certain granites and associated ar-
koses on Lake Timiscaming, Canada, by A. E. Barlow and W. F.
Ferrier. Brit. Assoc. Adv. Sci., Rept., pp. OnO-GOO.

On the origin and relations of tlie Grenville and Hastings Series in tlie
Canadian Laurentian. F. D. Adams and A. E. Barlow [with remarks
by R. AV. Ells]. Can. Record of Science, vol. vii, pp. .304-.316; also in
Am. Journ. Sci.. 4th series, vol. iii, pp. 173-180.

Summary report on a geological sui'vey of the Haliburton District, On-
tario, by F. D. Adams and A. E. Barlow. Geol. Surv. of Canada. Ann.
Rept.. ^-ol. X, pp. 44-r)fiA.

Notes on the petrography of certain roclvs from Lac des Mille Lacs,
Ontario. Geol. Surv. of Canada, Ann. Rept., vol. x, pp. 21)-31H.

Report on the geology and natural resources of the area included in
the Nipissing and Timiscaming map-sheets. Geol. Surv. of Canada,
Ann. Rept., vol. x, pt. I, pp. 1-.302.

Petrographical notes on a sericite schist from Harold Lake. Ontario.
Geol. Surv. of Canada, Ann. Rept. n. s., vol. x, p. 60H.
1808. Summary report on a geological survey of the Haliburton District. On-
tario, by F. D. Adams and A. E. Barlow. Geol. Surv. of Canada, Ann.
Rept.. vol. xi, pp. 106-lllA.

Petrographical notes on certain rocks from Fraser River (upper). Brit-
ish Columbia. Geol. Surv. of Canada, Ann. Rept., vol. xi, pp. 34-36D.

I'etrographical notes on certain rocks from Winnipeg Lake, Manitoba.
Geol. Surv. of Canada, Ann. Rept, vol. xi, pp. 26, 27G.

1899. Summary report on a geological survey of the Haliburton District, On-

tario, by F. D. Adams and A. E. Barlow. Geol. Surv. of Canada. Ann.

Rept., vol. xii, pp. 122-131A.
On the origin of some Archean conglomerates. Ottawa Naturalist, vol.

xii, pp. 205-217, pis. vi-ix.
Petrographicjil notes on certain rocks from Great Bear and Great Slave

Lakes District. Geol. Surv. of Canada, Ann. Rept., vol. xii; app. to

pt. C, pp. 29-36.
Petrographical notes on certain rocks from the iron ore deposits of the

Kingston and Pembroke Railway District, Ontario. Geol. Surv. of

Canada, Ann. Rept., vol. xii, pp. 81-911.

1900. Summary report on a geological survey of the Haliburton District, On-

tario, by F. D. Adams and A. E. Barlow. Geol. Surv. of Canada, Ann.
Kept., vol. xiii, pp. 127-129A.

BIBLIOGRAPHY OF A. E. BARLOW 17

Gravity separations of feldspars in dikes of Shefford Mount., Quebec.
Geol. Surv. of Canada, Ann. Rept., vol. xiii, p. 29L.

Tests on auriferous sands from sluice-boxes, Atlin, Britisli Columbia.
Geol. Surv. of Canada, Ann. Rept, vol. xiii, pp. 11-13A.
1!K)1. Summary report on a geological survey of the Sudbury District, On-
tario. Geol. Surv. of Canada. Ann. Rept., vol. xiv, pp. 143-147A.

Notes on ore from bore-hole, Hepworth, Ontario. Geol. Surv. of Can-
ada, Ann. Rept, vol. xiv, p. 261A.

Report on the origin, geological relations, and composition of the nickel
and copper depo.sits of the Sudbury Mining District, Ontario, Canada.
Geol. Surv. of Canada, Ann. Rept, vol. xiv, pt. H, 2.36 pp.

Petrographical notes on certain rocks from the Klondike District, Yu-
kon. Geol. Surv. of Canada, Ann. Rept., vol. xiv, pp. 10-22B.
1!)()2. Summary report on a geological survey in the Sudbury Mining District,
Ontario. Geol. Surv. of Canada, Ann. Rept, vol. xv, pp. 2.54-269A.
On the nepheline rocks of Ice River, British Columbia. Ottawa Nat-
uralist, vol. 16, pp. 70-76.

Dr. Alfred R. C. Selwyn. Dii-ector, Geological Survey of Canada, 1869-
1894. Ottawa Naturalist, vol. 16, pp. 171-177.

I'etrographieal notes on specimens from Bruce Mines District, Ontario.
Geol. Surv. of Canada, Ann. Rept., vol. xv, pp. 247A and 1()4S.
l!»(»;i. Petrography of rock specimens from British Coluinl)ia : (a) Tcxiida
and Vancouver Island, pp. 254, 25"); (h) west coast of Vancouver
Island, etc., etc., pp. 258-260. Ann. Rept. of Minister of Mines for
British Columbia for 1903.

1904. Summary report on ge(-)]ogical surveys in the Ontario Corundum dis-

tricts and Lake Temagami. Geol. Surv. of Canada, Ann. Rept., vol.
xvi, pp. 190-194A.
Notes on Craig Mine, Renfrew County, Ontario. Geol. Surv. of Canada,
Ann. Rept.. vol. xvi. pp. 15, 16S.

1905. I'etrographieal determinations of rock specimens from Texada Island,

British Columbia. Trans. Can. Min. Inst., vol. viii, pp. 175-176.
A hmdslide on the Lievre River, Quebec. Ottawa Naturalist, vol. 18,
pp. 181-190.

1906. On the nickel deposits of Webster, North Carolina. Trans. Can. Min.

Inst., vol. ix, pp. 303-316.

Report on some of the undeveloped zinc deposits of British Columbia.
Can. Dept. of Int., Mines Br., Rept. of the Commission to nivestigate
the seine resources of Briti.sh Columbia, pp. 273-293.

Summary report on the Quebec side of Lake Timiscaming. Summary
Rept., Geol. Surv. of Canada, 1906, pp. 113-118.

On the origin and relations of the nickel and copper deposits of Sud-
bury, Ontario, Canada. lOcon. Geol., vol. i, no. 5, pp. 4.54-466; uo. 6,
pp. 545-553.

1907. Report of a special committee on the correlation of the pre-Cambrian

rocks of the Adirondack Mountains. tlH> "original Laurentiaii area"
of Canada and East Ontario, by F. 1 ». .Vdaiiis and others. Journ. of
(ii'oi., vol. \~t. no. :;. |i]i. 191 217.
19(is. Tile oiigiti of (lie silxci- of .Fiiiiifs lovvusliip, iMonl ic.il Kivcr I >ist.rict,
Ontario. Tran.s. Can. Min. Inst, vol. xi, pp. 2.5(i-27.').

18 PKOCEEDINGS of the PHILADELPHIA MEETING

The silver veins of the Montreal River District, Canada. Miu. and Sci.

Press, vol. 97, Oct. .3, pp. 462-465.
The nepheline and associated alkaline syenites of Eastern Ontario, by

F. D. Adams and A. E. Barlow. Trans. Roy. Soc. Can., .3d ser., vol.2,

sec. 4, pp. 3-76.
I'JOU. Report on mining claims in the Montreal River Division. The German

Development Co., Ld., Rept. for 1909, pp. 5-21 ; also Can. Min. Journ..

vol. 30, pp. 51-54.
Report on the mining locations belonging to "Miller Lake and Everett

Mines, Ld." The German Development Co., Ld., Rept. for 1909, pp.

22-26; also Can. Min. Journ., vol. 30, pp. 57-58.

1910. Geology of the Haliburton and Bancroft areas, Ontario, by F. D. Adams

and A. E. Barlow. Geol. Surv. of Canada, memoir no. 6. No. 1082.
[French translation, no. 1187.]
Origin of asbestus. Trans. Can. Min. Inst, vol. xiii, pp. 438-443.

1911. Preliminary report on the geology and mineral resources of the Chi-

bougamau region, Quebec, by the Chibougamau Mining Commission.
A. E. Barlow, J. C. Gwillim, E. R. Faribault. Quebec Dept. of Colo-
nization, Mines, and Fisheries, 24 pp.
Report on the geology and mineral resources of the Chibougamau re-
gion, Quebec, by the Chibougamau IMining Commission. A. E. Barlow,
J. C. Gwillim, and E. R. Faril)ault. Quebec Dept. of Colonization,
Mines, and Fisheries, 224 pp.
1911. Memoir of David Pearce Penhallow. Bull. Geol. Soc. Am., vol. 22, pp.
15-19.

1913. Presidential address. Trans. Can. Min. Inst, vol. 16, pp. 4-14.
Excursion A2 : The Haliburton-Bancroft area of central Ontario, by

F. D. Adams and A. E, Barlow. (Guide Book No. 2, XI 1 Session.
Congros Geol. Internat, pp. 5-98.)
Account of Excursion A2, Haliburton-Bancroft, Ontario. Congres Geol.
Internat, Compte-Rendu, XII Session, Canada, 1913, pp. 960-963.

1914. Corundum, its occurrence, distribution, exploitation, and uses. Geol.

Surv. of Canada, No. 1022, Memoir No. 57 (now in press).

ALBERT SMITH BICKMOEE
BY GEORGE FREDERICK KUNZ

Albert Smith Bickmore was born in the coast village of Tenants
Harbor, in the town of Saint George, Maine, March 1, 1839. As in the
cases of most of those who in after life have made their mark in the
natural sciences, he already gave evidence as a child of his interest in
natural ol)jeets. This is testified to by some of his surviving relatives,
who recall that he was called a ''queer child" because he was constantly
hunting after butterflies, shells, and birds. A voyage to Bordeaux,
France, when a child, made on a ship of which his father was captain,
must have left a strong impression on a mind so sensitively alive to the
aspects of nature, and this early experience probably planted the seeds

BULL. GEOL. SOC. AM.

VOL. 26, 1914, 1>L. 2

-=^-t3 >

MEMOIR OF A. S. BTCKMORE 19

of his love for travel and exploration.^ After preparation in the district
school and in several academies, he entered Dartmouth College, gradu-
ating in 1860. His college expenses were partly paid l)y money earned
for teaching during the vacations. Four years' study under the great
]iatiiralist and geologist, Louis Agassiz, in the Lawrence Scientific Scliool
of Harvard University, prepared him for his later researches.

His extensive researches during his Oriental voyage were not only in
tlie field of natural science, in the narrowest sense, but included tlie
domain of ethnography, and liis discovery of the curious Ainu pco|)l('.
tlie aborigines of Japan, was an iuiporlant contribution to tliis science.
However, his long, ai'duous, and fnitlitul service in the American Museum
of Natural History was the crowning glory of his career. Tic bad charge
of the Department of i^iblic Instruction from 1S82 to 1!)04. His brief
professorship of natural history at Madison (now Colgate) University.
Hamilton, New York, Avas partly coincident with the undertaking of his
life task in building uj) our wonderTul ^luseum.

Professor Bickmore was the recipient of the following titles and de-
grees :

A. B., Dartmouth, 1800, A. M., 1863; B. S., Harvard, 1864; Tb. D.,
Hamilton, 1869, Dartmouth College, 1880; LL. D., Colgate, 1005; Life
Fellow, Eoyal Geographical Society, London; Fellow American Geograi)])-
ical Society, New York Academy of Sciences, A. A. A. S. : Trustee Amer-
ican Museum of Natural History, Colgate, U., Vassar College.

While studying under Prof. Louis Agassiz, whose only I'eniaining i)upil
is Dr. David Starr Jordan, of Leland Stanford University, be became
his assistant, and went to Bermuda, collecting for Cambridge Museum.
Ue also traveled in the East Indian Archipelago, China and Japan, Si-
beria, Moscow, Saint Petersburg, Berlin, and London during the years
from 1865 to 1868 ; became professor of natural history in j\radison (now
Colgate) Universitv, 1860 ; superintendent of the American Museum of
Natural History, 1860-1884, and in the same institution pi-ofessor in
charge of the Departinent of Public Instruction since 188"2. He again
Iraveb'd, in 1805 to 1004, gathering data and illustralions I'oi- lectures
on natural bistory, geography, and history, and be aftcrwai'd |)ublisbed
travels in the East Indian Archipelago in New York, London, and Jena,
l^rofessor Bickmore did his pai't in the Civil \\i\v as well, serving for
nine niontlis in the 44th Massachusetts N'olunleers in ISC-.^ and IS63.

Professor Bickmore. in 1875, was one of the handsomest and luoM
kindly men I had ever met. lie lold me. of his inception of the Museum

' Sco biogrnphicnl skrleli of l'ri>l'('ss(jr I'.ickiiuirc. hy .1. M. I'.., in the Wali'liinaii-Rx-
iUiiiniT, New York and Boston, August -'.'>. lull, i<. 11."'.).

20 PROCEEDINGS OF THE PHILADELPHIA MEETING

after returning from his "trip through China and northern Siberia."
He asked himself : "Could a great city like New York afford to be with-
out a museum of natural history?" With his ripe experience of travel,
his wide knowledge of natural history, and his love of it, fostered by that
pioneer naturalist, Louis Agassiz, his dream became a reality, and the
Museum is today greater than any of us had dared to hope. People have
often spoken of the thirteen buildings that Avould form the group com-
prising the Museum of Natural Histor}\ They thought of it as a curious
architectural plan for a gridiron building, but never realized that it would
become a fact. Today we have no less than six buildings.

All who knew liim will agree with the statement that while no one Jias
better succeeded in such effort than did the late Professor Bickmore in
obtaining gifts and favors for his cherished institution, he was never
uncomfortably insistent in his requests, l^ut almost invariably found it
possible to persuade the prospective donor that no better place could be
found for his specimens than the great museum, where not only the
former owner himself could see them under the very best conditions, but
they would afford pleasure and instruction to thousands of visitors.

I never knew Professor Bickmore to be in anything but a liappy mood.
He was frank, fearless, generous, kind, energetic. His whole ambition
was embodied in the success of the American Museum of Natural History.
Those were the days when the IMuseum had very little or no money, al-
though it was sustained by loyal and ambitious friends.

Of all those associated with the institution and its inception, only three
are now living: Hon. Joseph H. Choate, who has been a trustee through-
out the entire period of its existence, and the renowned naturalist. Dr.
Daniel Giraud Elliott, who, with the late Doctor Holder, the latter's son,
now Dr. Charles Frederick Holder, and Mr. Bargen, an accountant and
bookkeeper, formed the entire staff of the Museum when the doors of the
Arsenal were opened to admit the public to view the relatively small but
interesting and well chosen collection of that early day in the institution's
history.

A memorial meeting for Professor Bickmore was held January 29,
1912, at the American Museum of Natural History, short addresses being
made, among others, by Prof. Henry Fairfield Osborn, President of the
Museum; Cleveland II. Dodge, Joseph H. Choate, Dr. John M. Clarke,
and L. P. Gratacap, a curator of the Museum. No one was better quali-
fied to speak of the great work accomplished by Professor Bickmore in
connection with the founding and building of the Museum than Mr.
Choate, who drafted the charter and by-laws of the new institution and
who was one of the few survivors of those who actively supported the

BULL. GEOL. SOC. AM.

VOL. 26, 1914, PL. 3

*^^^^>^rr-cc>j^ C?<

\?-/a^<j^.

MEMOIR OF A. S. BICKMORE 21

project from the outset. Of the "Father of the Museum/' as Professor
Bickmore has been called, this speaker said that the great change in
public opinion as to the value and importance of natural history studies
was due in a greater degree to his iniluence than to any other single
cause.

The strong personal influence exercised by Louis Agassiz, among whose
many pupils, from 1861 to 18(55, was Albert S. Bickmore, is believed to
have contributed in large measure to the latter's enthusiastic devotion to
the idea of establishing a great museum of natural history. A similar
museum had already been projected by Agassiz for Harvard College.-
When Bickmore came to New York, in 18()5, he was introduced to Mr.
William Earle Dodge and proposed tiie mattei- to him. This was just
before Bickmore's departure for the Far East. Just before bis return
to the country he stopped for a while in London, where he met Sir
Eichard Owen, Director of the Museum of Natural History, and sul)-
mitted to him the plans for a New York museum which lie had l)een
slowly elaborating during his protracted journey. The hearty approval
which the English scientist bestowed upon these plans served to deepen
Bickmore's conviction of their value and practicability, and on his return
to New York he took up the matter with renewed ardor. One of the
most earnest workers in this cause was Theodore Tioosevelt, Sr., to whom
Bickmore was referred by Mr. Dodge, and soon by his efl'orts and those
of William Haines, Benjamin H. Field, and Eobert Colgate a number of
representative citizens became interested in the project, several of them
becoming members of tlie original board of trustees, composed of New
York's leading citizens.

MEIIOIR OF IIOKACK CAiri'Ki; HOVEY
BY JOHN M. CLARKE

The science of the earth seems to liold an especial attraction for the
servants of its ancient enemy, the Cburcli. As the contentious attitude
once assumed l)y the Church toward this science dissolved away into a
better balance and steadier growth, it is little wonder that some part of
the clergy luive shown a sincere |)ur[)ose to bctlci' acMjiuiinl Ibemselves,
by })ci'sonal touch, witli I be data of geology. Tbc developmeid of fbe
English facts and ideals in our science lias put upon tbc rolls names of
distinguished clerics, men who bave put aside all bias and have rendered

-The American Museum of Natural History, its origin, its history, and growth of
the departments to December 31, 1909, by Henry Fairfield Osborn, President. 2d ed.
New Yorif, 1911.

22 PROCEEDINGS OP THE PHILADELPHIA MEETING

a service unqualified by tradition or prejudice. American geology, too,
also acknowledges its obligations to, and tliis Society has admitted among
its ranks, many an ordained Christian minister.

Of these — indeed, among all of us — the subject of this testimonial lias
held a singular, if not unique, position, and in this necessarily brief
notice of his achievements in this science it is well that we remind our-
selves of his devoted service in other fields wliicli lie beyond the scope of
our present attention.

The Eev. Horace Carter Hovey, Doctor of Divinity, was born near
Eob Eoy, Fountain County, Indiana, January 28, 1833, and died at his
home in Newlmryport, Massachusetts, the place of his last pastorate,
July 27, 1914, thus in his 82d year. The blood in his veins, drawn from
both sides of his parentage, was of the good vintage of the English
yeomanry who established this nation. His parents had followed one oL'
the remoter paths of Puritan dispersion about Xew England, taking their
way from I])swich, through Brookfield, Maiden, and Manchester; thence
into Hanover, New Hampshire, and to Thetford, Vermont. From Ver-
mont, in the winter of 1831-1832, they went as home missionaries, with
the express object of establishing a Presbyterian institution of higher
education in the Wabash A^'alley. There, at Crawfordsville, the Eev.
Edmund Otis Hovey, the father, with his associates, founded AVabash
College, and there for more than forty years he served that institution,
holding all administrative offices from the lowest to the highest, except
the presidency, which he persistently declined. In this somewhat varied
scholastic career it was the sciences that invited and held his most con-
tinuous service, and through his special concern with geology Doctor
Hovey, senior, is fairly entitled to be counted among the pioneer geolo-
gists of the Middle AVest ; for even though he himself did not venture
into the field of authorship, he kept in personal touch with the leaders in
American geology — Dana, Hall, and Newberry. The scientific museum
of Wabash College today bears his name — the Hovey ]\ruseum — and this
important educational factor has been assembled about the nucleus of a
little lot of crystals and ores brought by his wife all the long way from
Vermont.

The inspiration and influence of such parentage, predisposed on both
sides to the love of science, could hardly fail to turn the heart of the son
toward tlie laboratory of nature. He was taught to observe: his eyes
and his mind were opened to things of woodland and valley, of rocks and
sky. The wondrous beds of crinoids in Coreys Bluff, of which all the
world now knows and specimens from which are to be found in most
geological museums, were discovered by him when a boy of nine years.

MEMOIR OF H. C. HOVEY 23

The well directed ej'es of this little shaver in science had already in tliis
single act done a thing which in real service the lifetime of another might
hardly equal. But love and comprehension of science was not a thing
that in those days, in such an atmosphere, could he safely j)ursued save
as an avocation from what was, to that generation, a more serious calling ;
and so the growing youth, having passed through the course at Wabash
College, graduated in 1853, and as students of that institution were
definitely designed for the Church, Mr. Hovey completed the purpose of
his training by a course in the liane Theological Seminary at Cincinnati.

Doctor Hovey was an active clergyman all his life and he was one of
the original Fellows of the Geological Society. He never pretended,
however, to be a professional geologist, even though he became expert and,
among us, final in experience and judgment in that phase of the science
now designated by the unlovely term speleology.

His study of caverns was begun in 1854 and was maintained with ever-
growing interest for sixty years. His zeal was fearless. The subter-
ranean world, with its unknowii mysteries of darkness and labyrinthine
mazes, held no fears for him, and he pursued, even at the age of seventy-
five, their bewildering ways in newly discovered parts of the Mammoth
Cave, through "which the routes were dangerous and difficult enough to
have taxed the nerve, the strength, and the agility of a young man.

His first published account of his explorations was in 1855 and related
to the Wyandotte Cave of Indiana. His last contribution to the litera-
ture of caves was an exhaustive bibliography of the Mammoth Cave (with
Dr. E. Ellsworth Call), which was published in 1914, and came to his
hands only a few hours before his death.

When Doctor Hovey began his labors, cave-hunting was little else than
a bizarre and venturesome underground diversion, seemingly impelled
by curiosity only, with a distant intangible liope of solving some hidden
problem. Today cave exploration is so far an orderly procedure, with
definite modes and objectives, as to have won a distinctive name, a dis-
tinctive organization, La Societe de Speleologie, and a distinctive organ,
Spclinica. In the charm of that far-reaching interest which bears on the
jH'iiiiitive history of tlic human race and its contemporaries, the American
caverns seem not yet to have a share, l)iit in their pliysical characters
ilioir 1)earing on broad problems of drainage, on the cliemistry of solution,
and on tlie tectonics of limestone plateaus (the caves to which Doctor
Hovey gave his especial attention) they are, in magnitude of area and
diversity of effects, hardly to be equaled. To these must be added their
M'ondrniiR and im|)rossivc beauty in domes and spii-cs. m crystal mounds
and ()palcsc(!iit pools, in glistering spectral icicles ;in(l resonant cnrillons,

24 PROCEEDINGS OF THE PHILADELPHIA MEETING

all tlie weird and fascinating devices of a Ijuried world, emerging from
the slime and dirt, the grime and damp, of the lower regions — in these
majestic demonstrations of phj'sical change and the vastitude of results
from 'persistent minor forces the American caves have perhaps few peers.

Doctor Hovey"s work may be estimated as having opened to the Avorld
a field of great interest and instruction in our country. To it we owe
our present extensive knowledge of the ]\Iammoth Cave, much of Avhat is
known of the Luray caverns, and so on along the line of American caverns
of note. His "Celebrated American Caverns" is a standard work; his
"Guide Book to the ]Mammoth Cave" has passed through fifteen editions ;
his contributions to the Encyclopedia Britannica are the summaries of
an authority, and in his bibliography will he found more than 100 titles
which testify to his unflagging and plenteous activities in popularizing
and disseminating knowledge of underground phenomena.

A few years after Doctor Hovey had written the first of his papers on
cave exploration (1858) the famous bone cave at Brixham, Devonshire,
was discovered. Its discoverers thought it important that it he scien-
tifically investigated and communicated their conviction to tlu^ Director
General of the Geological Survey, who decided that such operations did
not fall within the scope of that Survey. Yet this discovery, the explora-
tion of the contents of the cavern by Pengelly and Falconer, led to the
unfolding of the whole panorama of the ancient caves and cave life of
Britain. Since those years the caves of Europe have proven to be the
treasure chests of our human records, and while here in America we
must abide with a slenderer hope of such light; yet the life stories of the
American caverns, which have been illuminated by the discoveries of
Doctor Hovey and his associate, Doctor Call, are of great interest.

In their organic or inorganic phases these problems of the caves per-
tain to our science of geology, and it is our gratification that he who
labored on them so successfully was one of us.

Doctor Hovey was a cautious observer, a clear and forcible writer, and
brought to his scientific publications qualities which graced his chiefer
l^rofession. He taught his science as he could find opportunity. He
traveled much, and in these travels, on one occasion, had opportunity to
visit the caverns of central France under the guidance of Martel.

Upon Doctor Hovey's other service to his generation we can not dwell.
Labors for the Christian Commission during the last years of the Civil
War, in which he went through the battles of the Wilderness, North
Anna, and Cold Harbor; his civic activities in the various communities
of his pastorate — these have been recorded in other memorials. In later
years his appearance at our meetings was only occasional, but we do not

BIBLIOGRAPHY OF II. C. IIOVEY 25

forget his line presence, liis luiiidsome face, his courteous, winning, and
impressive personality.

BIBLIOGRAPHY

r.iathlosponsia. Trans. Kansas Acad. Sci., vol. iii, pp. 10-11. 1S74.
Discoveries in western caves. Am. Jour. Sci., 3d ser., vol. xvi, pp. 465-471.

December. 1878.
One hundred miles in Mammoth Cave. Scribner's Monthly Magazine, vol. x.x,

pp. 914-924. October, 1880.
lOiglity miles in Indiana caverns. Scribner's Monthly, vol. xix, pp. 875-887.

1880.
Recent discoveries, measurements, and temperature observiitioiis in Mammoth
Cave. Naturalist's Leisure Hour and Monthly Bulletin, No. 8, pp. 8-9.
August, 1881.
The tem])ei-ature of the Mauunoth Cave. Sciontiflc American. October 8, 1881.
The new Scylla and Charybdis. Scientific American. October, 1881.
The Mammotli Cave visited by the American Association for the Advancement

of Science. P.ull. Harvard Univ., No. 20. October. 1881.
Observations on the temperature of the Mammoth Cave, Kenlu(:k.\-. I'roc.

Conn. Acad. Arts and Sciences. November, 1881.
Hovey's explorations in the Mammoth Cave. Popular Sciciico Monllily. vol.

xvii. November, 1880. and January, 1881.
Coal dust as an element of danger in mining. Am. Joui'. Sci., 3d .ser., vol. xxii,

pp. 18-20. 1881.
Coal dust as an element of danger in mining shown by the explosion in the
Albion mines, November 12, 1880. Proc. Am. Assoc. Adv. Sci., vol. xxx,
pp. 68-69. 1882.
Cuide book to the Mammoth Cave of Kentucky. Robert Clarke & Company,

Cincinnati. 1882.
A remarkable case of retention of heat by the earth (abstract). Proc. Am.

Assoc. Adv. Sci., vol. xxx, pp. .39-40. 1882.
Celebrated American caverns, especially Mammoth, Wyandotte, ami Lura.\-.

Robert Clarke & Company, Cincinnati. 1882. Second edition. 1896.
Manunoth Cave. Encyclopedia Britannica, 9th and 10th editions, vol. xv, pp.

448-450. 1883.
Sui)ti'rranean map-making. Proc. Am. Assoc. Adv. Sci., vol. xxxi, pt. ii. ]ip.

345-346. 1883.
Guide book to the Mammoth Cave. 70 pages. Roliert Clarke & Company, Cin-
cinnati. 1884.
Niagara River, (iorge, and Falls. Scientific American Suppl., vol. 22, No. 558,

p. 8917. 1886.
The pits and domes of Mammoth Cave. I'roc Am. Assoc. Adv. Sci.. vol.

xxxviii, pp. 2.53-2.55. 1889.
Idem. Scientific American. October, 1889.

American saltpeter caves. Scientific American, vol. 65, p. 3. 1891.
Some measurements in llie Manuiiotb ("ave of Indiana. Scientilic .Vineiican,

vol. 65. p. 52. is'.tl.
Diamonds iu meteors. Scieiililic .\iim ii<an, vol. 65. \>. 129. 18!tl.

26 PROCEEDINGS OF THE PHILADELPHIA MEETING

Tlie latest facts about the Megalonyx. Scientific American, vol. 65, p. 161.

1891.
Mammotli Cave, Kentncliy. Bull. Am. Geog. Soc, vol. xxiii, pp. 47-79. 1891.
-Vppendixes to Mammoth Cave guide book, 1.3th edition. Appendix A, on sub-
terranean fauna and flora. iVppendix I?, on Ganter Avenue. 1891.
A visit to Chalcedony Park, Arizona. Scientific American, vol. 67, p. 5,5. 1892.
On the rim and in the depths of the Grand Canyon. Scientific American, vol.

67, pp. 87-89. 1892.
Kansas salt. Scientific American, vol. 66, p. 289. 1892.
The Grand Canyon of the Colorado. Scientific American, vol. 66, pp. .392-39.3.

1892.
A remarkable instance of recent erosion. Scientific American, vol. 68, p. 152.

1893.
The Isles of Slioals (New Hampshire). Scientific American Suppl., No. 1035,

pp. 16547-16548. 1895.
The making of Mammoth Cave. Scientific American, vol. 75, p. 351. 1896.
The colossal cavern of Kentucky. Scientific American, vol. 75, p. 183. 1896.
Geological notes on the Isles of Shoals (abstract). Proc. Am. Assoc. Adv. Sci.,

vol. xliv, pp. 136-137. 1896.
Mammoth Cave, its environs and contents. Jour. School of Geography, vol. i,

pp. 133-139. May, 1897.
Our saltpeter caves in time of war. Scientific American, vol. Ixxvi, p. 291.

1897.
Mammoth Cave of Kentucky. (H. C. Hovey and R. Ellsworth Call.) John P.

Morton »& Company, Louisville, Kentucky. 112 pages. 1897.
The Aven Armand, Lozere, France. Scientific American, vol. 78, pp. 228-229.

1898.
The life and work of James Hall, Lli. D. Am. Geol., vol. xxiii, pp. 137-168.

1899.
Mapping the Mammoth Cave. Scientific American Suppl., No. 1229. June 22,

1899.
Facts about Megalonyx. Scientific American Suppl., No. 1300, p. 20839. 1900.
The lead and silver mines of Newbury. Scientific American Suppl., No. 1328,

p. 21284. 1901.
Balloon measurements of Mammoth Cave's height. Scientific American, vol.

89, p. 147. 1903.
The colossal cavern of Kentucky. Scientific American Suppl., No. 1455. No-
vember 21, 1003.
Colossal cavern. Spelunca, t. v, pp. 57-01. 1904.
Strange mazes and chasms in Mammoth Cave, with diagram of the Mtelstrom

and photograph of John M. Nelson, the guide. Scientific American Suppl.,

No. 1540, p. 24680. 1905.
A Mammoth Cave cathedral; some new discoveries of interest. Scientific

American Suppl., No. 1651, p. 125. 1907.
Recent explorations in Mammoth Cave, with a revised map of the cave (ab-
stract). Science, n. s., vol. xxviii, p. 381. September 18, 1908.
Hovey's hand-book of the Mammoth Cave. John P. Morton & Company, Ijouis-

ville, Kentucky. 64 pages. 1909.
Mammoth Cave Baedeker's United States, p. .581. 1!)09.

Ill— nm.r,. Ceol. Soc. A.m., Voi,. 'JO, 1014

BULL. GEOL. SOC. AM.

VOL. 26, 1914, PL. 4

BIBLIOGRAPHY OF H. C. HOVFA' 27

Kaemper's discoveries in the Mammoth Cave. Scientific American, vol. 100,

p. 388. 1909.
Mammoth Cave. Encyclopedia Britanuica, 11th edition, vol. xvii, pp. 5.31-53.3.

1911.
Mammoth Cave, Kentucky, with an account of Colossal Cavern. (H. C. Hovey

and R. Ellsworth Call. ) John P. Morton & Company, Louisville, Kentucky.

131 pages. 1912.
Bibliography of Mammoth Cave, Kentucky. (H. C. Hovey and R. Ellsworth

Call.) Spelunca, t. ix, No. 73. September, 1913.

MEMOIR OF NEWTON HORACE WINCHELL
BY WARREN UPHAM

In the seventh generation of descent from Eobert AVinchell, the British
immigrant wlio founded this family in America, living in Windsor, Con-
necticut, from 1635 until his death, in 1669, Newton Horace Winchell
was born in Northeast, Dutcliess Connty, New York, December 17, 1839,
and died in Minneapolis, Minnesota, May 2, 1914. His father, Horace
Winchell, and his mother, Caroline McAllister Winchell, were highly
esteemed school teachers, and l)otli were excellent singers. The father,
residing on the ancestral farm, was greatly interested in religious de-
nominational reforms, peaceable arbitration of national disputes, and
abolition of slavery, and to advance these reforms he published many
pamphlets.

Newton Horace Winchell in boyliood attended the public school and
academy at Salisbury, Connecticut, and at the age of sixteen years he
began teaching in a district school of his native town. Two years later,
in 1858, he entered the University of Michigan, where his eldest l)rother,
Alexander, was the professor of geology. The next eight years wore spent
in studies at the university and in school teaching, alternately, the schools
(aught being in Ann Arbor, Grass Lake, Flint, Kalamazoo, Colon, and
Port Huron, Michigan. Previous to his graduation at the university, in
1866, he had been two years the superintendent of the public schools in
Saint Clair, Michigan; and next, after graduation, he was again superin-
tendent of schools at Adrian, in that State, for two years, 1867-1869. He
received from his Alma Mater the degree of Master of Arts in 1867.

Like his brother. Prof. Alexander Winchell, with whose family he had
his home during the early part of his university studies, at Ann Arbor,
Michigan, Newton Horace devoted himself mainly to the scioiico of
geology, with allied interest in all branches of natural history. In Mich-
igan he did iiiiich early work for Iddany, and in bis latest years, afler iiis
geological sui\('\ of Minnesota was completed, lie pcrl'ornicd very valu-

28 PROCEEDINGS OF THE PHILADELPHIA MEETING

able services for the Minnesota Historical Society on the archeology and
ethnology of this State and the iSTorthwest.

During a year, in 1869-1870, he was an assistant to Prof. Alexander
Winchell on the Geological Survey of Michigan, and later in 1870 he
visited and reported on the copper and silver deposits of New Mexico.
In 1871 he assisted Prof. J. S. Kewberry, the State geologist of Ohio,
surveying and reporting on twenty counties in the northwestern part of
tliat State.

In Julv, 1872, N". H. Winchell was invited bv President William W.
Folwell, of the University of Minnesota, to take up the work then recently
ordered by the legislature for a survey of the geology and natural history
of this State, to be done under the direction of the Board of Eegents of
the University. In this work he continued twenty-eight years, until 1900 ;
and during the first seven years, until 1879, he performed also the full
duties of the university professorship of geology. Later he relinquished
teaching, aside from occasional lectures, and gave all his time to the
diversified duties of the State survey and the curatorship of the university
museum.

In the su miner of 1874 Professor Winchell accompanied General Cus-
ter's expedition to the Black Hills, lu'ought back many valuable additions
for the museum, and prepared a report which contains the first geological
map of the interior of the Black Hills.

In 1873 he was one of the organizers of the Minnesota Academy of
Natural Sciences, which he served during three terms as president, and
he continued as one of its most active members throughout his life.

He was a Fellow of the American Association for the Advancement of
Science and presided over its geological section at the Philadelphia meet-
ing in 1884. He was one of the chief founders of this Geological Society
of America, in 1889, and was its president in 1902. He was a member
of national societies of mineralog)^ and geology in France and Belgium.
In the International Congress of Geologists he became a member in 1888,
l:)eing reporter for the American Committee on the nomenclature of the
Paleozoic series ; contributed papers in French to its subsequent meetings
at Boulogne and Zurich, and attended its triennial meeting of August,
1913, in Toronto.

Under appointment by President Cleveland in 1887, Professor Win-
chell was a member of the United States Assay Commission. His geo-
logical reports received a diploma and medal at the Paris Exposition of
1889 and a medal at the World's Fair in Chicago in 1893.

TIo was the chief founder of the American Geologist, a monthly maga-
zine, wliich was published in Miniicajiolis. under liis editorship, during

MEMOIR OF N. II. WINCHELL 29

eighteen years, 1888-1905, in two volumes yearly, forming a series of
thirty-six volumes. This work, in which he was much assisted by Mrs.
Winchell, greatly promoted the science of geology, affording means of
publication to many specialists and amateurs throughout this country.
It also brought out many biographic sketches, with portraits, of the prin-
cipal early American workers in this wide field of knowledge.

In one of the bulletins of the Minnesota Geological Survey, entitled
"The Iron Ores of Minnesota," 430 pages, with maps, published in 1891,
Prof. N. IT. Winchell had the aid of his son, Horace Vaughn Winchell ;
and in a text-book, "Elements of Optical Mineralogy," 502 pages, 1909,
he was associated in authorship with his younger son. Prof. Alexander
Newton Winchell, of the University of Wisconsin. During parts of the
later years of the Minnesota survey he was aided by his son-in-law, Dr.
Ulysses S. Grant, professor of geology in the jSTorthwestern University,
Evanston, Illinois.

In 1895-1896 Professor and Mrs. K. H. Winchell spent about a year
in Paris, France, and again he was there during six months in 1908, his
attention being given mainly during each of these long visits abroad to
special studies and investigations in petrology.

Por the Geological and Natural History Survey of Minnesota, Pro-
fessor Winchell published twenty-four Annual Reports, being one each
year for the years from 1872 to 1894, inclusive, and the last in this series
being for the years 1895-1898, published in 1899. These reports of
progress of the survey range in size from 42 pages to 504 pages, com-
prising many very important papers on the observations of the geology
of all parts of the State; also on its ornithology, entomology, botany,
paleontology, etc., by Professor Winchell and his assistants. In the last
of these annual reports a general index of all the series fills 106 pages.

Ten bulletins of this Survey were published in the years 1887 to 1894,
inclusive, ranging from 37 to 430 pages, the largest being on "The Iron
Ores of Minnesota," before mentioned, and the last, by J. Edward Spurr,
"The Iron-bearing Pocks of the Mesabi Range in Minnesota," 268 pages.

The final reports of the Geology of Minnesota form six quarto vol-
umes, and the third of these volumes, on Paleontology, is bound in two
parts. Volume I, ])ublishcd in 1884, comprises the reports of the coun-
ties in the southern third of the State; Volume II, published in 1888,
treats of the counties in the next third part of the State, jn-occeding
northward, and Volume IV, publisliod in 1S9!», contains reports on the
rnoro noiihci-n counties, including tlic great belts of iron-ore deposits
called the \'ci'iiiilioii and Mesabi ranges. Volume V, 1900. by N. H.
Winchell and 1'. S. (|i-ant, deals willi (lie structural and petrographic

30 PROCEEDINGS OF THE PHILADELPHIA MEETING

geology of the Taconic and Archean rocks. A geological atlas forms
Volume VI, published in 1901, in which are reprinted all the map plates,
eighty-eight in number, of the preceding volumes, with brief descriptions
for each, written by Professor Winchell; and a general map is also pre-
sented, showing the approximate areas of the geologic systems below the
drift.

My association with Prof. K. H. Winchell began in June, 1879. Com-
ing from the Geological Survey of New Hampshire, in which I had been
for several years an assistant, I was thenceforward one of the assistants
of the Minnesota Survey six years, until 1885, and again in 1893 and
1894. In the meantime and later, while I was an assistant geologist of
the surveys of the United States and Canada, on the exploration, map-
ping, and 2:>ubli cation of the Glacial Lake Agassiz, which occupied the
basin of the Eed liiver and of lakes Winnipeg and Manitoba, my frequent
association with Professor Winchell kept me constantly well acquainted
with the progress of his Minnesota work. Since the spring of 1906 he
had been in the service of the Minnesota Historical Society, having charge
of its Department of Archeology. During all these thirty-five years I
had intimately known him and had increasingly revered and loved him.
Besides being a skilled geologist, Newton Horace Winchell was a good
citizen, a Christian in faith and practice, beloved by all who knew him.

Among the many special investigations which Prof. N. H. Winchell
published during the forty-five years of his active work as a scientist,
author, and editor, none probably has been more widely influential on
geologic thought and progress than his studies and estimates of the rate
of recession of the Falls of Saint Anthony, cutting the Mississippi Riv^r
gorge from Fort Snelling to the present site of the falls in Minneapolis.
This investigation, first published in 1876, gave about 8,000 years as the
time occupied by the gorge erosion, which is likewise the approximate
measure of the time that has passed since the closing stage of the Ice Age,
or Glacial period, when the border of the waning ice-sheet was melted
away on the area of Minnesota.

Artificially chipped quartz fragments and rude aboriginal implements
found in the Mississippi Valley drift at Little Falls, in central Minnesota,
belonging to the time of final melting of the ice-sheet there, and other
traces of man's presence at nearly the same time, or even much earlier,
in numerous other localities of the southern part of our great North
American glaciated area, have led Professor Winchell and others, as the
late Hon. J. V. Brower, Professors G. F. Wright and F. W. Putnam, and
myself, to a confident belief that mankind occupied this continent during
the later part of the Ice Age, or even quite probably much earlier in that

MEMOIR OF N. H. WINCHELL 31

period, and possibly even before our continental glaciation began. This
very interesting line of investigation was the theme of the last paper
written by Professor Winchell, entitled "The Antiquity of Man in Amer-
ica Compared with Europe," which he presented as a lecture before the
Iowa Academy of Sciences in Cedar Falls, Iowa, on Friday evening, April
24, only a week before he died.

The work on which he was engaged for the Minnesota Historical
Society during his last eight years, based on very extensive collections,
by Hon. J. Y. Brower, of aboriginal implements from Minnesota and
other States west to the Eocky Mountains and south to Kansas, enabled
Professor Winchell to take up very fully the questions of man's antiquity
and of his relation to the Ice Age. From that later work resulted a
quarto volume, published in 1911, entitled ''The Aborigines of Minne-
sota," 761 pages, with many illustrations and about 500 maps of groups
of Indian mounds.

This last volume of his publications and the twenty-four Annual Ee-
ports and six quarto volumes of Final Eeports of the Geological and
Natural History Survey of Minnesota are monuments more enduring
than bronze, which will be consulted and studied during all the coming
centuries by investigators of the origin and history of the races of man-
kind and by all interested in geology or earth lore, not only in the schools
and universities of Minnesota, but of all the world.

Newton Horace AVinchell was married to Miss Charlotte Sophia Imus,
of Galesburg, Michigan, August 24, 1864. She survives him, as also do
all their five children, namely, Horace Vaughn Winchell, geologist and
mining assayer, Minneapolis ; Ima Caroline, Mrs. Frank N. Stacy, Min-
neapolis; Avis, Mrs. Ulysses Shennan Grant, Evanston, Illinois; Prof.
Alexander Newton Winchell, Madison, Wisconsin, and Louise, Mrs. D.
Draper Dayton, Minneapolis.

Professor Winchell had enjoyed somewhat good health until the last
week, although suffering in some degree with a chronic trouble of many
years, and his death resulted from a needed surgical operation done on
the preceding day.

He was my friend and it is hard to say Farewell !

BIBLTOORAPIIY

ISOl. (';i(;ilo;,'uo of plants in the lower itcninsula of Miolii,i.'an. Fii-st liicniiial

r('i)oit of the (Jeol. Surv. Midi., iMil, pp. Utri-.'HT.
ISO'.). ])oes the earth move on its axisV .Micliigaii Teacher. May and .June,
1801).
Tlie Ciiel)o.vjj;an re^'ion. Arichi^'an Farmer. Dec, ISOl).
The An Sahle. Detroit Trihuiie (tw.i paixM-.s). Dec, ISOJ*.

PROCEEDINGS OF THE PHILADELPHIA MEETING

1870. The Thunder Bay region. Detroit Free Press. April 11, 1870.
A sunken hil^e and its outlet. Detroit Tribune. 1870.

Phenomena of the post-Tertiary. University Chronicle, Ann Arbor.

August, 1870.
Geological notes in the Thunder Bay region. Alpena Pioneer (six

papers). Oct.-Dec, 1870.

1871. The building stones of Michigan. American Builder (three papers).

June, 1871.

The geology of Putnam County, Ohio. Putnam County Sentinel. Oct.
1871.

Sketch of Crawford County, Ohio. 1871.

The glacial features of Green Bay of Lake Michigan, with some obser-
vations on a probable former outlet of Lake Superior. Am. Jour.
Sci., 3d ser, vol. ii, pp. 15-19. July, 1871.

1872. Sketch of Delaware County, Ohio. Delaware Gazette. July 8, 1872.
The surface geology of northwestern Ohio. Proc. Am. As.soc. Adv. Sci.,

vol. xxi, pp. 152-186. 1872. Abstract in Am. Jour. Sci., vol. iv, pp.
321-322. 1872.

1873. The first annual report of the Geological and Natural History Survey

of Minnesota, 1872. First and second editions identical, 112 pp. 8vo.
This report contains :

General sketch of the geology of Minnesota, pp. 40-48, 60-118.
Preliminary geologic map of Minnesota.

Chart of geologic nomenclature, intended to express the relation
of Minnesota to the great geological series of the earth.
The drift-deposits of the Northwest. Popular Science Monthly. June

and July, 1873, vol. ill, pp. 202-210, 286-297.
Notes on the drift-soils of Minnesota. Fourth annual report of the

commissioner of statistics of Minnesota, 1873.
The Devonian limestones in Ohio. Proc. Am. Assoc. Adv. Sci., vol. xxii,

pp. 100-104. 1873.
The geology of Sandusky, Seneca, Wyandot, and Marion counties, Ohio.
Kept. Geol. Surv. Ohio, vol. i. pp. 591-645; 4 maps. Columbus, 1873.

1874. The geology of Ottawa, Crawford, Morrow, Delaware, Van Wert, Union.

Paulding, Hardin, Hancock, Wood, Putnam, Allen, Auglaize, Mercer,
Henry, and Defiance counties, Ohio. Kept. Geol. Surv. Ohio, vol. ii,
pp. 227-438. Columbus, 1874.
The second annual report of the Geological and Natural History Survey
of Minnesota, 1873. 219 pp. Svo. St. Paul, 1874. This report con-
tains :

The Belle Plaine salt well, pp. 79-87.
Peat, pp. 88-127.

The geology of the Minnesota Valley, pp. 127-212.
On the Hamilton in Ohio. Am. Jour. Sci., 3d ser., vol. vii. pp. 395-398.

1874.
Report concerning the salt spring lands due the State of INIinnesota,

1874. 26 pp. 8vo.
Geological notes from early explorers in the Minnesota Valley. Bull.
Minn. Acad. Sci., vol. i, pp. 89-101, 153-156. 1874.

BIBLIOGRAPHY OF N. H. WINCHELL 33

Report on the copper and silver rlistricts of southwestern New Mexico.
Mines and Mining west of tlie Rocky ^Mountains, pp. 3o5-343. Wasli-
ingtou, 1874.
187"). Report of tlie curator of the Museum. Dec. 14, 1874. Univ. Minn.
Report for 1874.

Notes on the Big Woods. Read before the Minnesota Hort. See, 3875.
Trans. Hort. Soc.

The economical geology of the region of Cheboygan and old Mackinac in
the counties of Presque Isle, Cheboygan, and Emmet, State of Michi-
gan. Report of the Michigan I'.oard of Agriculture for 1873, pp. 103-
107. 1875.

The third annual report of the Geological and Natui-al History Survey
of Minnesota, 1874. 44 pp. 8vo. St. Paul, 1875. This report contains :
Report on the geology of Freeborn County, pp. 5-19, with a col-
ored map.
Report on the geology of Mower County, pp. 20-3G, with a colored
map.

Report of a reconnaissance of the Black Hills of Dakota, made in the
summer of 1874 by Capt. William Ludlow. Geological report by N. H.
Winchell, pp. 21-65, 4to ; contains the first geological map of the in-
terior of the Black Hills. Also in U. S. A. Rept. Chief Engineers,
1874 ; Appendix PP, pp. 1131-1172. Washington, 1875.

Charcoal table : Used in the mineralogical laboratory of the University
of Minnesota. 1875.

Note on lignite in the Cretaceous of Minnesota. Am. Jour. Sci., 3d ser.,
vol. X, p. 307. 1875.

1876. Vegetable remains in the drift-deposits of the Northwest. Proc. Am.

Assoc. Adv. Sci., vol. xxiv, pp. 43-56. 1876.
On the parallelism of Devonian outcrops in Michigan and Ohio. Proc.

Am. Assoc. Adv. Sci., vol. xxiv, pp. 57-59. 1876.
Notes on a deep well drilled at East Minneapolis in 1874-1875. Bull.
Minn. Acad. Sci., vol. i, pp. 187-189. 1876. Reprinted in the fifth
report on the Minnesota Survey.
The fourth annual report on the Geological and Natural History Survey
of Minnesota for 1875. 120 pp. 8vo. St. Paul, 1876. This report
contains :

Report on the geology of Fillmore County, pp. 251-303, with a
map. Republished in the "History of Fillmore County," in
1882.

1877. The fifth annual report of the Geological and Natural History Survey

of Minnesota for 1876. 248 pp. Svo. St. Paul, 1877. This report
contains :

Tlie geology of Houston County, i)p. 9-50, with a map.
The geology of Hennepin Comity, pp. 131-201, widi .i ni:i|). Tliis
report includes a discussion of tlie recession <>r the Falls of
St. Anthony.
The Cretaceous in MiiincsctM. T'lill. :\Iiiiii. Ac:id. S<m.. vol. i. pp. 317-

349. 1877.

34 PROCEEDINGS OF THE PHILADELPHIA MEETING

1878. The sixth annual report of the Geological and Natural History Survey

of Minnesota for 1877. 226 pp. Svo. Minneapolis, 1878. This report
contains :

The water supply of the Red River Valley, pp. 9-42.
Reconnaissances (in Wright, Goodhue, and Rice counties and

along Northern Pacific Railroad), pp. 43-49.
The geology of Morrison County, pp. 50-5.3.
The geology of Ramsey County, pp. 66-92, with a map.
The geology of Rock and I'ipestone counties, pp. 93-111, with a
map.
The recession of the Falls of .St. Anthony. Quart. Jour. Geol. Soc. Lon-
don, vol. xxxiv, pp. SS6-901. Nov., 1878.

1879. The seventh annual report of the Geological and Natural History Survey

of Minnesota for 1878. 123 pp. 8vo. ^Minneapolis, 1879. This re-
poi't contains :

Sketch of the work of the season of 1878 (a preliminary report
on the stratigraphy and mineral resources of the northern part
of the State), pp. 9-25.
Section of a deep well at Emmetsburg, Iowa. Bull. Minn. Acad. Sci.,

vol. 1, pp. 387-388. 1879.
Minnesota (geological formations). Macfarlane's Am. Geol. R. R.
Guide, pp. 145-147. 1879.

1880. The eighth annual report of the Geological and Natural History Survey

of Minnesota for 1879. 183 pp. 8vo. St. Paul, 1880. This report
contains :

Lithology (microscopic examination of rocks), pp. 10-22.
The Cupriferous series at Duluth, pp. 22-26.
Paleontology (Lingula, Crania, Orthis), pp. 60-69.
Castoroidcs ohioensis, pp. 181-183.
Annual address of the President of the Minnesota Academy of Science.

Bull. Minn. Acad. Sci., vol. i, pp. 389-401. 1880.
The Cupriferous series in Minnesota. Proc. Am. Assoc. Adv. Sci., vol.

xxix, pp. 422-425. 1880.
Preliminary report on the building stones, clays, limes, cements, roofing,
flagging, and paving stones of Minnesota. Geol. and Nat. Hist. Surv.
Minn. 37 pp. 8vo. 1880.
The ancient copper mines of Isle Royale (abstract). Bull. Minn. Acad.
Sci., vol. i, p. 29. 1880. Printed in full in Popular Science Monthly,
vol. xix, pp. 601-620. 1881.

1881. The ninth annual report of the Geological and Natural History Survey

of Minnesota for ISSO. 403 pp. 8vo. St. Paul, 1881. This report
contains :

Preliminary list of rocks (field descriptions and notes on 442
crystalline rocks fi-om northern Minnesota), pp. 10-114.

Paleontology (Orthis and Strophomena) , pp. 115-122.

The water supply of the Red River Valley, pp. 156-174.

The Cupriferous series in Minnesota, pp. 385-387.
Ball's observations on arctic ice, and the bearing of the facts on the
glacial phenomena of Minnesota. Am. Jour. Sci., 3d ser., vol. xxi, pp.
358-360. 1881.

BIBIJOGRAPHY OF N. H. WINCHELL 35

Ciirular letter to the geologists of America (as chairman of a com-
mittee for the organization of what became the Geological Societj-
of America). 1S81. Eepriiited in Am. Geol., vol. vi, pp. 184-185.
1890.

The State and higher education. Bull. Minn. Acad. Sci., vol. ii, pp. 1-18.
1881.

Typical thin sections of the Cupriferous series in Minnesota. I'roc.
Am. Assoc. Adv. Sci., vol. xxx, pp. 160-166. 1881.

1882. The tenth annual report of the Geological and Natural History Survey

of Minnesota for 1881. 254 pp. 8vo. St. Paul, 1882. This report
contains :

Preliminary list of rocks (field descriptions and notes on 39.3

rock samples from northern Minnesota), pp. 9-122.
The Potsdam sandstone, pp. 123-130.
Typical thin sections of the rocks of the Cupi'iferous series in

Minnesota, pp. 137-143.
Geological notes on Minnesota (translation of "Geologische Noti-
zen aus Minnesota," by .J. H. Kloos. Zt. d. d. geol. Gesell., vol.
xxiii, pp. 417-448; 648-6.52. with map, 1871), pp. 175-200.
The geology of the deep well drilled by G. C. Whelpley at Min-
neapolis, at the "C" Washburn mill, pp. 211-217.
Resume d'une communication sur la nomenclature geologique dans
I'echelle stratigraphique. Congres geol. internat. C. R., 2d session,
pp. 642-646. 1882.
Report of the section of mineralogy. Bull. Minn. Acad. Sci., vol. ii, pp.

390-416. 1882.
Geology of the Minnesota Valley. History of the Minnesota Valley, pp.
169-176 (700-707). 1882.

1883. The eleventh annual report of the Geological and Natural History Sur-

vey of Minnesota for 1882. 220 pp. Svo. Minneapolis, 1883. This
report contains :

The mineralogy of Minnesota, pp. 5-29.

The crystalline rocks of Minnesota (translation of "Uebor die
krystallinischen Gesteine von Minnesota in Nord-Amerika," by
A. Streng and J. H. Kloos. Neues Jahrb., 1877, pp. 31-56, 113-
138, 225-242), pp. 30-85.
Note on the age of the rocks of the Mesabi and A'ermilion iron
districts, pp. 168-170.
Resolutions on the death of Darwin. Bull. Minn. Acad. Sci., vol. ii, pp.

386-387. 1883.
The Lake Superior rocks. Science, vol. i, p. 334. 1883.
Clay pebbles from I'rinceton, Minn. Proc. Am. Assoc. Adv. Sci., vol.
xxxii, p. 238. 18&3.

1884. The twelfth annual report of the Geological and Natiir.il History Sui-

vey of Minnesota for 1883. 410 pp. 8vo ; 23 plates. Minneapolis.
1884. This report contains :

The comparative strength of Minnesota and New England gran-
ites, pp. 14-18. Also in ab-stract in I'roc. \m. Assoc. Adv. Sci.,
vol. xxxii, pp. 249-250. 1884.

36 PROCEEDINGS OF THE PHILADELPHIA MEETING

Minnesota (buikling stones). 10th Census U. S., Report on building

stones for ISSO, pp. 244-256. (Vol. X.)
The crystalline rocks of the Northwest. Am. Nat., vol. xviii, pp. 984-
1001. 1SS4. Proc. Am. Assoc. Adv. Sci., vol. xxxiii, pp. 36.3-379. Ab-
stract. Science, vol. iv, pp. 238-240. 1884. 13th Ann. Kept. Geol. and
Nat. Hist. Surv. Minn., pp. .36-38.
The geology of Minnesota ; volume I of the final report of the Geolog-
ical and Natural History Survey of Minnesota. 697 pp. 4to; 43
plates and 52 figures. Minneapolis. 1884. This report contains :

Historical sketch of explorations and surveys in Minnesota, pp.

1-110.
The general physical featui'es of Minnesota, pp. 111-141.
The building stones of Minnesota, pp. 142-203.
The geology of Houston, Winona, Fillmore, Mower, Freeborn,
Pipestone, Rock, and Rice counties, pp. 207-324, .347-366. 376-
393, 533-561, 648-673.

1885. The thirteenth annual report of the Geological and Natural History

Survey of Minnesota for 1884. 196 pp. 8vo; 4 plates. St. Paul, 1885.
This report contains:

Notes of a reconnaissance into Pope County. May, 1884, pp. 10-19.
Notes of a trip across the Mesabi range to Vermilion Lake, pp.

20-24.
The Vermilion iron ores, pp. 25-35.
The Humboldt salt well in Kittson County, pp. 41-44.
The deep well at Lakewood cemetery, Minneapolis, pp. 50-54.
Notes on the artesian wells at Mendota, Hastings, Red Wing,
Lake City, and Brownsville, and on the deep well at St. Paul,
pp. 55-64.
Fossils from the red quartzite at Pipestone, pp. 65-72.
The mineral exhibit of Minnesota at the New Orleans Exposition, 1884.

5th Ann. Rept. Cal. State Mineralogist for 1885, pp. 167-169.
Notes on the sandstone of Taquamenon Bay, Lake Superior. Am. Jour.
Sci., 3d ser., vol. xxix, pp. 339-340. 1885.

1886. The fourteenth annual report of the Geological and Natural History

Survey of Minnesota for 1885. 353 pp. 8vo ; 2 plates. St. Paul, 1886.
This report contains :

Notes on some deep wells in Minnesota, pp. 11-16 ; 348-353.

New species of fossils, pp. 313-318.

A supposed natural alloy of copper and silver from the north

shore of Lake Superior, pp. 319-324.
Revision of the stratigraphy of the Cambrian in Minnesota, pp.
325-337.
The Taconic controversy in a nutshell. Science, vol. vii, p. 34. 1886.

1887. The fifteenth annual report of the Geological and Natural History Sur-

vey of Minnesota for 1886. 446 pp. 8vo; 2 maps. St. Paul, 1887.
This report contains :

Report of N. H. Winchell (on iron ores and areal geology and
stratigraphy of northern Minnesota), pp. 211-.398.
Notes on classification and nomenclature for the American Committee

BIBLIOGRAPHY OF N. H. WINCH ELL 87

of the International Geological Congress. March, 1887. Am. Nat.,
vol. xxi, pp. 693-700. 1887.
The iron-bearing formations of northeastern Minnesota. Bull. Minn.
Acad. Sci., vol. iii, pp. 168-169. 1887.
ISSS. The sixteenth annual report of the Geological and Natural History
Survey of Minnesota for 1887. 504 pp. 8vo. St. Paul, 1888. Thi.s
report contains :

The original Huronian, pp. 13-40.
The Marquette and Gogebic iron regions, pp. 40-60.
Grand Marais, Gunflint Lake, Tower, etc. (ai-eal study of geology
of northeastern Minnesota ) , pp. 60-129.
The Geology of Minnesota ; volume II of the final report of the Geo-
logical and Natural History Survey of Minnesota. 695 pp. 4to; 42
plates and 32 figures. St. Paul, 1888. This report contains :

The geology of Wabasha, Goodhue, Dakota, Hennepin, Ramsey,

and Washington counties, pp. 1-101, 264-398. The chief feature

of the volume is the final discussion of the recession of the

Falls of St. Anthony, with illustrations showing their position

from the time of their discovery by Hennepin to 1857.

The Animikie black slates and quartzites and the Ogishke coiigloni-

erate of Minnesota the equivalent of the "Original Huronian/' .\iii.

Geol., vol. i, pp. 11-14. 1888.

Irving and Chamberlin on the Lake Superior sandstones. Am. Geol.,

vol. i, pp. 44-51. 1888.
Some objections to the word Taconic considered. Am. Geol., vol. 1. pp.

162-172. 1888.
A great primordial quartzite. Am. Geol., vol. i, pp. 173-178. 1888.
The proposed Geological Society (with C. H. Hitchcock). Am. Geol.,

vol. i, pp. 394-395. 1888.
Report of the subcommittee on the Lower Paleozoic. Presented for the
American committee to the International Congress of Geologists, Lon-
don session, 1888. Am. Geol., vol. ii, pp. 193-224. 1888.
Some thoughts on eruptive rocks, with special reference to those of
Minnesota. Proc. Am. Assoc. Adv. Sci., vol. xxxvii, pp. 212-221. 1888.
1889. The seventeenth annual report of the Geological and Natural History
Survey of Minnesota for 1888. 273 pp. 8vo. St. Paul, 1889. This
report contains :

General report of progress made in the study of the crystalline
rocks of Minnesota, pp. 5-74.
The history of geological surveys in Minnesota. Bull. 1, Geol. and Nat.

Hist. Surv. Minn. 37 pp. 8vo. St. Paul. 1889.
Natural gas in Minnesota. Bull. 5, Geol. and Nat. Hist. Surv. Minn.

39 pp. 8vo. St. Paul, 1889.
Exhaustion of anthracite coal. ,\ra. Geol., \o\. iii, pp. 45-48. 1889.
A now glacial theory. Am. Geol., vol. iii. iip. 138-140. 1889.
Geological Society of America. Am. (Jcol.. vol. iii, pp. 140-146. 1SS9.
Natural science at the University of Minnesota. Am. Geol.. vol. iii, pp.

165-169. 1889.
The origiji of jtrairics. .\m. Geol., vol. iii, pp- 182-1.8.3. 1889.

38 PROCEEDINGS OF THE I'HILADELPHIA MEETING

The so-called Huronian rocks in the vicinity of Sudbury, Ontario. Bull.

Minn. Acad. Sci., vol. iii, pp. 183-185. 1889.
American petrographical microscopes. Am. Geol., vol. iii. pp. 225-230.

1889.

Unconformity at the falls of the Montmorenci. Am. Geol., vol. iii, pp.

333-334. 1889.
Sandy simoon in the Northwest. Am. Geol., vol. iii, pp. 397-399. 1889.
Benjamin Franklin Shumard, a sketch. Am. Geol., vol. Iv, pp. 1-6.

1889.
On a possible chemical origin of the iron ores of the Keewatin in Min-
nesota (with H. V. Winchell). Am. Geol., vol iv, pp. 291-300, 383-

386. 1889. Proc. Am. Assoc. Adv. Sci., vol. xxxviii, pp. 235-242. 1889.
Methods of stratigraphy in studying the Huronian. Am. Geol., vol. iv,

pp. 342-357. 1889.
Notice of the discovery of Lingula and Paradoxides in the red quartz-

ites of Minnesota. Bull. Minn. Acad. Sci., vol. iii, pp. 103-105. 1889.
Professor Irving and the Keewatin series and the origin and horizon of

the iron ores of the Vermilion Lake series (with H. V. Winchell).

Am. Geol., vol. iv. pp. 383-386. 1889.
1S!K). The eighteenth annual report of the Geological and Natural History

Sui'vey of Minnesota for 1889. 234 pp. 8vo. St. Paul, 189U. This

report contains :

Record of field observations in 1888 and 1889 (studies of crystal-
line rocks of northeastern Minnesota), pp. 7-63.
The Brenham, Kiowa County, Kansas, meteorites (with J. A. Dodge).

Am. Geol.. vol. v, pp. 309-312 ; vol. vi, pp. 370-377. 1890.
A sketch of Richard Owen. Am. Geol., vol. vi, pp. 135-145. 1890.
The pre-natal history of the Geological Society of America. Am. Geol.,

vol. vi, pp. 181-194. 1890.
The Ta conic iron ores of Minnesota and western New England (with

H. y. Winchell). Am. Geol., vol. vi, pp. 263-274. 1890.
Quebec not in conflict with Taconic. Am. Geol., vol. vi, pp. 310-311.

1890.
What constitutes the Taconic Mountains? Proc. Am. Assoc. Adv. Sci.,

vol. xxxix, pp. 246-247. 1890. Also Am. Geol., vol. vi. p. 247. 1890.
The eastern equivalents of the Minnesota iron ores. Read before Minn.

Acad. Sci., Oct. 7, 1890. Pul dished in Iron Ores of Minnesota, pp.

411-419.
Northern Pacific Railroad. Macfarlane's Geol. Railway Guide, 2d ed.,

pp. 258-259. 1890.
1891. The iron ores of INIinnesota ; their discovery, development, geology,

origin, and comparison with those of other mining districts (with

H. V. Winchell). 430 pp. 8vo ; 41 plates and three maps. Bull. 6,

Geol. Nat. Hist. Surv. Minn. Minneapolis, 1891.
Museums and their purposes. A lecture, May, 1891 ; published in No. 1

of St. Paul Academy of Science. 1891. .
A letter to the Minnesota Horticultural Society, describing certain

maps of tlie Stale <>f Miiuiesota. Rept. Minn. Hort. Soc, is;)], pj).

296-299.

innLlOGKAPHY OF N. H. WINCIIELL 39

Mining (in Minnesota). Minn. Blue Boole, pp. .306-.308. 1891.

Alexander Winchell. Am. Geol., vol. vii. p. 19-5. 1891.

The orenitic hypothesis. Am. Geol., vol. viii. pp. 110-114. 1891.

The International Congress of Geologists. Washington meeting. Am.

<»eol.. vol. viii. pp. 24.3-2.58. 1891.
Jean N. Nicollet. A sketch of his life. Am. Geol., vol. viii, pp. 34.3-352.

1891.
Recent studies in spherulitic crystallization. Am. Geol., vol. viii. pp.

387-392. 1891.
1892. The nineteenth annual report of the Geological and Natural History

Survey of Minnesota for 1890. 255 pp. 8vo ; 41 figures and 2 plates.

Minneapolis, 1892. This report contains :

Geognostic and geographic observations in the State of Minne-
sota (a partial translation of "Geognostische und geographisclie
Beobachtungen in Staate Minnesota." Zeit. Gesell. fiir Erd-
kunde. Berlin, vol. xii, pp. 266-.320, 1877), pp. 81-121.
The geoogy of the iron ores of Minnesota. Trans. Geol. Soc. Australia,

vol. i, part 14. pp. 171-180. 1892.
Memorial sketch of Alexander Winchell. Bull. Geol. Soc. Am., vol. 3,

pp. 1-13. 1892.
Archean eruptive rocks of Finland. Am. (ic^d.. vol. ix, pp. 49-52. 1S92.
Alexander Winchell; an editorial trii)ute (witli E. W. Claj'pole). Am.

Geol., vol. ix. pp. 71-148. 1892.
The so-called Laurentian limestones at St. John, New Brunswiclv. Am.

Geol., vol. ix, pp. 198-200. 1892.
New species of Brachiopoda from the Trenton and Hudson River

groups of Minnesota (with Charles Schuchert). Am. Geol., vol. ix.

pp. 284-294. 1892.
The Kawishiwin agglomerate. Am. Geol., vol. ix, pp. 3.59-368. 1892.
An approximate interglacial chronometer (three plates). Am. Geol.,

vol. X. pp. 09-80. 1892.
Some problems of the Mesabi iron ore. Am. Geol., vol. x, pp. 109-179.

1892.
The United States Geological Survey. Am. Geol., vol. x, pp. 179-181.

1892.
The topographical map of the United States. Am. Geol., vol. x. ])i).

.304-310. 1892.
The iron-beai-ing rocks of Minnesota. Abstract. Bull. Minn. Acad. Sci.,

vol. iii. pp. 277-280. 1892.
isiC!. The twentieth aiiiiual rei)()rt of the Geological and Natural History

Sui'vey of Minn«'sota for 1891. 344 pp. 8vo ; 12 jilates. Minneapolis,

189.3. This re|)ort contains:

'I'lic fr\stalliii(' rocks; some preliminary considcr.il inns .-is \n

tiieir structui-es and origin, pp. 1-28.
Field notes, pp. 29-.34.
Oxide of manganese, pp. .321-.322.
The Noriaii nt" ihr Xmniwcsl. rrcfatory nofc (<> Bull. 8, Geol. Nat.

Hist. Sui-\. .Minn., pii. i-x\\i\. IS!).",.
Tile geology of Hennepin ('oinity. .Vtwaler's Jlislor.\ of Minneapolis,

chapter vi. 1893.

40 PROCEEDINGS OF THE PHILADELPHIA MEETING

Froudescent hematite. Am. Geol., vol. xi, pp. 20-21. 1893.

The unit of geological mapping for State siuneys. Am. Geol., vol. xi,

pp. 44-47. 1893.
The topographical work of the United States Geological Survey. Am.

Geol., vol. xi, pp. 47-.jr). 1893.
The Illinois State Museum. Am. Geol., vol. xi, pp. 109-110. 1893.
I'rofessor Wright's book a service to science. Am. Geol., vol. xi, p. 194.

1893.
I'rehistoric America, by Stephen D. Peet. (A review.) Am. Geol., vol.

xi, pp. 349-352. 1893.
Northwestern Columbian Museum (late the Minneapolis Exposition).

A circular prepared and printed at Chicago, Nov., 1893.
The twenty-lirst annual report of the Geological and Natural History

Survey of Minnesota for 1892. 171 pp. 8vo; 2 plates, 10 figures.

Minneapolis, 1893. This report contains :

Summary statement and comparative nomenclature, pp. 1-4.
Field observations of N. H. Winchell in 1892, pp. 79-160.
Sponges, graptolites, and corals from the Lower Silurian in Minnesota

(with Charles Schuchert). Advance pages from "The Geology of

Minnesota," volume iii, of the final report of the Geological and Nat-
ural History Survey of Minnesota, pp. 55-59. Minneapolis, 1893.
The Lower Silurian brachiopoda of Minnesota (with Charles Schu-
chert). Advance pages from "The Geology of Minnesota," volume iii,

of the final report of the Geological and Natural History Survey of

Minnesota, pp. 333-474. Minneapolis, 1893.
Report of the State Board of Geological Survey (Michigan) for the

years 1891 and 1892. 192 pp. 8vo. Lansing, 1892. (A review.) Am.

Geol., vol. xi, pp. 344-349. 1893.
1894. The twenty-second annual report of the Geological and Natural History

Survey of Minnesota for 1893. 210 pp. 8vo ; 7 plates. Minneapolis,

1894. This report contains :

List of rock samples (with geological notes), pp. 5-17.
The exhibit of the Survej' at the Columbian Exposition, pp. 201-
202.
Increase Allen Jjapham. Am. Geol., vol. xiii, pp. 1-38. 1894.
Pebbles of clay in stratified gravel and sand. Glacialists' Magazine,

vol. i, pp. 171-174. 1894.
Artesian water supply for Minneapolis ; letter to the City Council.

Saturday Spectator, Aug. 12, 1894. 5 pp.
L'extension du systeme Taconique vers I'ouest. Congres Geologique

Intern., 1894, pp. 272-308.
The Columbian Exposition. The crystalline rocks. Am. Geol., vol. xiv,

pp. 46-47. 1894.
The mineral industry. Am. Geol., vol. xiv, pp. 185-187. 1894.
The origin of spheroidal basalt. Am. Geol., vol. xiv, pp. 321-326. 1894.
A sketch of geological investigation in Minnesota. Jour. Geol., vol. ii,

pp. 692-707. 1894.
Sketch of John Locke. Am. Geol., vol. xiv, pp. 341-356. 1894.
A new meteorite : Minnesota No. 1. Am. Geol., vol. xiv, p. 389. 1894.

BIBLIOGRAPHY OF N. H. WINCHELL 41

1895. The twenty-third annual report of the Geological and Natural History
Survey of Minnesota for 1894. 255 pp. 8vo ; 3 plates. Minneapolis,
1895. This report contains :

The origin of the Archean greenstones, pp. 4-35.
The progress of mining, pp. 215-217.
List of rock samples, pp. 238-240.
The Geology of Minnesota ; final report of the Geological and Natural
History Survey of Minnesota, volume iii, part 1. 474 and Ixxv pp.
4to; 42 plates and 34 figures. Minneapolis, 1895. This report con-
tains :

Historical sketch of investigation of the Lovper Silurian in the

Upper Mississippi Valley (with E. O. Ulrich), pp. ix-liii.
Note on other Cretaceous fossils in Minnesota, pp. 53-55.
Sponges, graptolites, and corals from the Lower Silurian in Min-
nesota (with Charles Schuchert), pp. 55-59.
The Lower Silurian brachiopoda of Minnesota (with Charles
Schuchert), pp. 33.3-374.
The age of the Galena limestone. Am. Geol.. vol. xv, pp. .33-39. 1895.
The source of the Mississippi. Am. Geol., vol. xvi, pp. 323-326. 1895.

See also Minn. Hist. Soc. Coll., vol. viii, part 2, pp. 226-231. 1896.
The feldspars. Am. Geol.. vol. xvi, pp. 51-58. 1805.
Crucial points in the geology of the Lake Superior region. A .series of
ten articles, as follows :

The stratigraphic base of the Taconic or I^ower Cambrian. Am.

Geol., vol. XV, pp. 153-162. 1895.
The paleontologic base of the Taconic or Lower Cambrian. Am.

Geol., vol. XV, pp. 229-234. 1895.
The eruptive epochs of the Taconic or Lower Cambrian. Am.

Geol., vol. XV, pp. 295-304. 1895.
Canadian localities of the Taconic eruptives. Am. Geol., vol. xv,

pp. 356-363. 1895.
Steps of progressive research in the geology of the Lake Su-
perior region prior to the late Wisconsin Survey. Am. Geol.,
vol. xvi, pp. 12-20. 1895.
The Keweenawan according to the Wisconsin geologists. Am.

Geol., vol. xvi, pp. 75-86. 1895.
A rational review of the Keweenawan. Am. Geol.. vol. xvi, pp.

150-162. 1895.
The synchronism of the Lake Superior region with other por-
tions of the Nortii American continent. Am. Geo!., vol. xvi,
pp. 205-213. 1895.
The latest eruptives of the Lake Superior region. Am. Geol.,

vol. xvi, pp. 269-274. 1895.
Comparative taxonomy of the rocks of the Lake Superior region.
Am. Geo!., vol. xvi, pp. 331-337. 1895.
189G. Sur la met6orite tomb^e le 9 Aout, 1894, pr(^s do Fisher, Minnesota.
C. R., Acad. Sci., vol. cxxii, pp. 681-682. 1896.
Sur un cristal de labrador (l\i gabbio de Minnesota, r.iill. S<i<-. Miii.
France, vol. xix, pp. 90-92. 1896.

IV — Bull. Geol. Soc. Am., Vol. UG, 1014

42 PROCEEDINGS OF THE PHILADELPHIA MEETING

Laeroix's axial goniometer. Am. Geol., vol. xvii, pp. 79-82. 1896.
Microscopic cliaracters of tlie Fislier meteorite. Am. Geol., vol. xvii, pp.

173-176; 234-238. 1896.
Di.scovery and development of the iron ores of Minnesota. Minn. Hist.

Soc. Coll., vol. viii. pp. 25-40. 1896.
Volcanic ash from the north shore of Lake Superior (with U. S. Grant).

Am. Geol., vol. xviii, pp. 211-218. 1896.
The Arlington iron : Minnesota No. 2. Am. Geol., vol. xviii, pp. 267-

271. 1896.
The Black River limestone at Lake Nipissing. Am. Geol., vol. xviii,

pp. 178-179. 1896.
The missing link. Am. Geol.. vol. xviii, pp. 179-181. 1896.

1897. The Geology of IMinnesota; final report of the Geological and Natural

History Survey of Minnesota, volume iii, part 2. pp. 475-1081 and
Ixxvi-cliv, 4to; 48 plates and 133 figures. Minneapolis, 1897. This
report contains :

The Lower Silurian deposits of the Upper Mississippi province :
a correlation of the strata with those in the Cincinnati, Ten-
nessee, New York, and Canadian provinces, and the strati-
graphic and geographic distribution of the I'ossils (with E. O.
Ulrich). pp. Ixxxiii-cxxviii.
An important ai<l to the investigator and general student. Am. Geol.,

vol. xix. pp. 209-210. 1897.
Some new features in the geology of northeastern Minnesota. Am.

Geol., vol. XX, pp. 41-51. 1897.
Light in the East. Am. Geol., vol. xx, pp. 128-129. 1897.
The Missouri Geological Survey. Am. Geol., vol. xx, pp. 181-184; 270-

271. 1897.
The Fisher meteorite. Its chemical and mineral composition. Am.

Geol., vol. XX, pp. 316-318. 1897.
The geological chronology of Renevier. Am. Geol., vol. xx, pp. 318-321.

1897.
The close of the twentieth volume. Am. TJeol., vol. xx, pp. 403-405.

1897.
The Taconic according to Renevier. Am. Geol., vol. xx, pp. 405-407.

1897.
Minnesota quartzite. Stone, vol. xiv, pp. 122-125. 1897.

1898. A new ii'on-bearing horizon in the Keewatin in Minnesota. Proe. Lake

Sup. Mg. Inst., vol. V, pp. 46-48. 1898.
Relation of geology to topography ; discussion of a paper by J. C. Bran-

ner. Trans. Am. Soc. Civ. Eng., vol. xxxix. pp. 83-84. 1898.
The determination of the feldspars. Am. Geol., vol. xxi, pp. 12-49.

1898.
Some i-esemblances between the Archean of Minnesota and of Finland.

Am. Geol., vol. xxi, pp. 222-229. 1898.
The significance of the fragmental eruptive debris at Taylor's Falls,

Minn. Am. Geol., vol. xxii, pp. 72-78. 1898.
The question of differentiation of magmas. Am. Geol., vol. xxii, pp.

113-123. 1898.

BIBLIOGRAPHY OP N. H, WINCHELL 43

The oldest known rock. Abstract. Proc. Am. Assoc. Adv. Sci., vol.

xlvii, pp. 302-303; Science, vol. viii, p. 504. Am. Geol., vol. xxii, pp.

262-263. 1898.
Note on the characters of mesolite from Minnesota. Am. Geol., vol.

xxii, pp. 228-230. 1898.
The origin of the Archean igneous rocks. Am. Geol., vol. xxii, pp. 200-

310. 1898.
Thomsonite and lintonite from the north shore of Lalce Superior. Am.

Geol., vol. xxii, pp. 347-349. 189S.

1899. The twenty-fourth annual report of the Geological and Natural History

Survey of Minnesota for 1895-1898. 284 + xxviii pp. 8vo. Minne-
apolis, 1898. This report contains :

Summary statement (of work, museum, library, cost, and results

of the Survey), pp. vii-xxviii.
Rock samples collected in 1896-1898 (with geological notes), pp.

1-84.
General index of the annual reports of the Minnesota Survey
[reports i-xxiv], pp. 179-284.
The (Jeology of Minnesota; final report of the Geological and Natural
History Survey of Minnesota, volume iv. 630 pp. 4to; 79 plates and
114 figures. St. Paul, 1899. This report contains :

Preface (discussion of classification of .\rchean), pp. xiii-xx.
Geology of Carlton County, pp. 1-24.
Geology of St. Louis County, pp. 212-265.
Geology of Lake County, pp. 266-312.
Geology of (parts of) the Mesabi iron range, pp. 358-398.
Geology of the Pigeon Point plate, pp. 502-521.
Geology of the Vei-milion Lake plate, pp. 522-549.
Geology of the Carlton plate, pp. 550-565.
Geology of the Duluth plate, pp. 566-580.
Thalite and bowlingite fi-om the north shore of Lake Superior. Am.

Geol., vol. xxiii, pp. 41-44. 1899.
Chlorastrolite and zonochlorite from Isle Royale. Am. Geol., vol. xxiii,

pp. 116-118. 1899.
Common zeolites from the Minnesota .shore of Lake Superior. .\m.

Geol., vol. xxiii, pp. 17(J-177. 1899.
The optical characters of jacksonite. Am. Geol., vol. xxiii, pp. 250-251.

1899.
Adularia and other secondary minerals from the copper-bearing rocks.

Am. Geol., vol. xxiii, pp. 317-318. 1899.
rH)ewinson-Lessing's classification of rocks .-iihI differentiation of mag-
mas. Am. Geol., vol. xxiii, pp. .346-.369. IS!)!).

1900. The Geology of Minnesota; final report of the (Jeological and Natural

History Survey of Minnesota, volume \. 1027 and xxvii pp. 4to; 6
plates and 55 figures. St. Paul, 1900. This report contains:

I'refaco (classification of Taconic and Archean), pp. xxiii-xxvii.

Structni'al geology, ]ip. 1-74.

Petrographic geology of l]i(< crystalline rocks of .Miniiesol.i (wilb
Tl. S. (Jrant), p]h 75-9.36.

Mineralogy and petrology of Miiuiesota, pjt. 957-999.

44 PKOCEEDINGS OF THE PHILADELPHIA MEETING

Geological Survey of Michigan, volume vi, parts i and ii (a review).

Am. GeoL, vol. xxv, pp. 122-126. 1900.
1901. The Geology of Minnesota ; final report of the Geological and Natural

History Survey of Minnesota, volume vi, atlas of 90 plates, 4to. St.

Paul, 1901. Twenty-eight plates and all the synoptical descriptions

are by N. H. Winchell.
Retreat of the ice-margin across Minnesota (abstract). Science, vol.

xiii, pp. 509-510. 1901.
Croll's theory I'edivivus. Am. Geol., vol. xxvii, pp. 174-178. 1901.
(^Tlacial lakes of Minnesota. Bull. Geol. Soc. Am., vol. xii, pp. 109-128.

1901.
The Archean of the Alps. Am. Geol.. vol. xxviii, pp. 189-200. 1901.
Edward Waller Claypole. Am. Geol., vol. xxviii, pp. 247-248. 1901.
The origin of Australian iron ores. Am. Geol., vol. xxviii, pp. 248-250.

1901.
Fundamental changes in the Archean and Algoukian as understood by

Professor A'^an Hise, of the United States Geological Survey. Am.

Geol., vol. xxviii, pp. 385-388. 1901.
19U2. Sketch of the iron ores of Minnesota. Am. Geol.. vol. xxix, pp. 154-162.

1902. Also published in Proc. Int. Mg. Cong., 4th session, pp. 136-140.

1902.
Some geologic evidence of the deluge. Chicago Record Herald, May

Jl, 1902.
The Sutton Mountain. Am. Geol., vol. xxx, pp. 118-120. 1902.
The Lansing (Kansas) skeleton. Am. Geol.. vol. xxx. pp. 189-194. 1902.
The geology of the Mississippi Valley at Little Falls, Minnesota. Me-
moirs of Exi)loration in the Basin of the Mississippi, vol. v, Kakabi-

kansing, pp. 89-104. 1902.
The American Monthly .Journal of Geology and Natural Science. Am.

Geol., vol. xxx, pp. 62-64. 1902.
Regeneration of clastic feldspars. Abstract. Science, vol. xv, p. 85.

1902. Printed in full in Bull. Geol. Soc. Am., vol. 13, pp. 522-525.

1903.
1903. Some results of the late Minnesota Geological Survey. Am. Geol.. vol.

xxxi, pp. 246-253. 1903.
Was man in America in the Glacial period? Presidential address, Geol.

Soc. Am., Dec. 30, 1902. Bull. Geol. Soc. Am., vol. 14, pp. 1.33-152.

1903.
The Pleistocene geology of the Concannon farm, near Lansing, Kansas.

Am. Geol., vol. xxxi, pp. 263-308. 1903.
Geological and archeological excursion to Nehawka, Nebraska. August

14, 1902. Nebraska Board of Agriculture, report for 1902, pp. 314-317.
Metamorphism of Laurentian limestones of Canada. Am. Geol., vol.

xxxii, pp. 385-392. 1903.
(Jranite. Address at unveiling of the Coronado obelisk at Logan Grove,

l\ansas, August 12, 1902. Memoirs of Exploration in the Basin of

the Mississippi, vol. vii, Kansas, pp. 87-91. 1903.
1!)04. Tlu' evolution of climates. Am. Geol., vol. xxxiii, pp. 116-122. 1904.
\\liere did life begin? Am. Geol., vol. xxxiii, pp. 185-189. 1904.
i'eleliths. Am. Geol., vol. xxxiii, pp. 319-325. 1904.

BIBLIOGRAPHY OP N. H. WINCHELL 45

The colossal bridges of Utah. Am. Geol., vol. xxxiv, pp. 189-192. 1004.

The Baraboo iron ore. Am. Geol., vol. xxxiv, pp. 242-253. 1904.

The stone reefs of Brazil. Am. Geol., vol. xxxiv, pp. 319-324. 1904.

Professor Winchell's notes on a very brilliant meteorite. Poimlar As-
tronomy, vol. xii, pp. 553-555 ( misnumbered 252-255). 1904.

Notes on the geology of the Hellgate and Big Blackfoot valleys. Mon-
tana. Abstract. Bull. Geol. Soc. Am., vol. 15, pp. 576-578. 1904.

Notes on the geology of the Hellgate Valley between Missoula and
Elliston, and northward to Placid Tjalie, in Montana. Abstract. Sci-
ence, vol. xix, pp. 524-525. 1904.

1905. Deep wells as a source of water supply for Minneapolis. 29 pp.. 4 pis.

Published by citizens, Minneapolis, 1905. Also in Am. Geol.. vol.

XXXV, pp. 266-291. 1905.
Another meteorite in the Supreme Court. Am. Geol., vol. xxxvi, pp.

47-49. 1905.
The Willamette meteorite. .\m. Geol., vol. xxxvi, jip. 250-257. 1905.

1906. The Keweenawan at Lake of the Woods in Minnesota. Abstract. Sci-

ence, vol. xxiii, p. 289. 1906.
Glacial lakes of St. Louis and Nemadji. Abstract. Bull. Mia. Acad.
Sci., vol. iv. No. 2, p. 208. 1906.

1907. Origin of the word Canada. Nat. Geog. Mag., vol. xviii, p. 215. 1907.
Pre-Indian inhabitants of North America. Records of the Past, vol. vi.

pp. 145-157; 163-181; 17 figs. 1907.
Pre-Columbian elephant medals found in Minnesota. Am. Antliin]).,

vol. ix, pp. .358-361. 1907.
A white man's stone cairn. Am. Anthrop., vol. ix, pp. 654-055. 1907.
The Cuyuna iron range. Econ. Geol., vol. ii, pp. 565-571. 1907.
The massacre of the Verendrye party at Lake of the Woods. Magazine

of History, vol. vi, pp. 225-235. 1907.

1908. Migration of the early Babylonian civilization. Records of the I'ast,

vol. vii, p. 176. 1908.
The prehistoric aborigines of Minnesota and their migrations. Pop-

Scj. Monthly, vol. Ixxiii, pp. 207-225. 1908.
Sees no danger in artesian water. Minneapolis Tribune. Sept. 13, 1908.
Mining and quarrying. Minnesota in Three Centuries, vol. iv, pp. 375-

388. 1908.
Structures of the Mesabi iron oi-e. Proc. L. Sup. Mg, Inst., vol. xiii. pp.

189-204, 8 figs. 1908.

1909. Elements of Optical Mineralogy : an introduction to microscopic petrog-

raphy, with description of all minerals whose optical elements are
known, and tables arranged for their determination niicroscoincally
(with Alexander N. Winilu-ll). pp. viil, 502, 8vo ; 350 figures mikI 4
plates. New York, 1909.

Habitations of the Sioux in Miiniesota. Wisconsin Archeologist, vol.
vii, pp. 155-164. 1909.

A diamond drill core section ol the Mesabi rock.s. 1. Megascopic char-
acters. Proc. L. Sup. Mg. Inst., vol. xiv, pp. 156-178. 1909.

The Kensington rune stone, and report for the Mu.seum committee.
Norwegian-American, Nortlilield. Miiui. 1909.

46 PROCEEDINGS OF THE PHILADELPHIA MEETING

Possible pre-Glacial human remains in tlie region of Wasliington, D. C.
Records of tlie Past, vol. viii, pp. 249-252. 1909.

1910. A diamond drill core section of the Mesabi rocks. II. Microscopic char-

acters. III. Remarks on the foregoing section. Pi-oc. L. Sup. Mg.

Inst., vol. XV. pp. 100-141. 1910.
Hennepin at the Falls of St. Anthony. Bull. Minn. Acad. Sci., vol. iv,

pp. 3S0-3S4. 1910.
Prehistoric aborigines of Minnesota and their migrations. Abstract.

P.uU. Minn. Acad. Sci.. vol. iv, pp. 37S-379. 1910.
Extinct Pleistocene mammals of Minnesota. Bull. Minn. Acad. Sci.,

vol. iv, pp. 412-422; 2 pi. 1910.
The Kensington rune stone. A preliniinai\v report by the Museum

Committee of the Minnesota Historical Society. (With bibliography

by Mr. Holand.) 66 pp. 8vo ; 5 pi. St. Paul, 1910. Also in Minn.

Historical Society Collections. \ol. x\-. pi). 221-286. 1915.

1911. Ala]) of Minnesota, showing the mean annual rainfall and the subsoils.
The iron ore ranges of Minnesota and their differences. Bull. Minn.

Acad. Sci., vol. v, pp. 43-68, 24 figs. 1911.
The genesis of certain greensauds of Alinnesota. Abstract. Science,

vol. xxxiii. pp. 462-463. 1911.
A diamond drill core section of the Mesabi rocks. IV. Geological bear-
ing of the foregoing described facts. Proc. L. Sup. Mg. Inst., vol. xvi,

pp. 61-69. 1911.
The Aborigines of Minnesota. A report based on the collections of

Jacob V. Brower, and on the field surveys of Alfred J. Hill and T. H.

Lewis, pp. xiv, 761, 4to ; with 36 pi., 26 inserts, and 642 figs. Minn.

Hist. Society, St. Paul, 1911.
Were the Outagami of Iroquois origin? Miss. Valley Hist. Assoc, vol.

iv, pp. 1S1-18S. 1911.

1912. Progress of opinion as to the origin of the Lake Superior iron ores.

Bull. Geol. Soc. Am., vol. 23, pp. 317-328. 1912.
Saponite. thalite, greenalite, greenstone. Bull. Geol. Soc. Am., vol. 2.3,

pp. 329-332. 1912.
Memoir of Christopher Webber Hall. Bull. Geol. Soc. Am., vol. 23, pp.

28-30. 1912.
Paleolithic artifacts from Kansas. Records of the Past. vol. xi, pp.

174-178. 1912.

1913. The weathering of aljoriginal stone artifacts; a consideration of the

paleoliths of Kansas. Coll. Minn. Hist. Soc, vol. xvi. pt. 1, pp. xiv,
186; 19 pis., 20 figs. 1913.
The age of the Mesabi iron-bearing rocks of Minnesota. Abstract. Sci
ence, vol. xxxvii, p. 457. 1913.

1914. The founders of the Academy. Bull. Minn. Acad. Sci., vol. v, pp. 108-

116. 1914.

L'bomme primitif dans le Kansas. C. R. Congres Intern. Anthrop.
Archeol. Geneve, 1914.

The antiquity of man in Auierii a compared with Europe. Lecture de-
livered before the Iowa Academy of Science, April 24, 1914.

BULL. GEOL. SOC. AM.

VOL. 26, 1914, PL. 5

MEMOIR OF JOSEPH LE CONTE 47

MEMOIR OF JOSEPH LE CONTE ^

BY HERMAN L. FAIRCHILD

The story of Le Conte's life has been so well told in his autobiography^
and in memorials^ published at the time of his death that only a brief
outline will be necessary here.

On his father's side he was Huguenot, his ancestors coming to America
about 1690. His mothers family was Puritan. Louis, the father of
Joseph, was a native of New York and a graduate of Columbia College.
He studied medicine "to better care for the slaves on his father's plan-
tation." His liome was Woodmanston plantation, Liberty County,
Georgia, in a Puritan colony, orthodox and exclusive. Joseph was the
fifth child and youngest son. His mother, Anne Quartermain, a Puritan,
died when Joseph was three years old, and "he was brought up by his
father with the most tender care. The father was a very remarkable
man — a good physician, a skillful chemist and naturalist, a great hunter,
fond of all manly sports, and a passionate lover of nature. Young Le
Conte owed much to his father's training, but he was partly prepared for
college by Alexander Stephens." Joseph was born February 26, 1823,
and died in Yosemite Valley July G, 1901.

At the age of 18, young Le Conte graduated at Athens College, and in
1845, at the age of 22, he graduated in medicine in the College of Phy-
sicians and Surgeons in Xew York and began the practice of medicine in
his home district in Georgia. In 1847 he married Caroline E. Nisbit.

He found the life of a country physician unsatisfactory, and, becoming
interested in osteology, he went to Cambridge, Massachusetts, in 1850,
as a pupil of Agassiz. In 1851 he accompanied Agassiz in the latter's
study of the Florida coral reefs.

Turning from medicine to natural science, he became, in 1852, Pro-
fessor of Science at Oglethorpe University, Midway, Georgia, teaching
physics, chemistry, and "natural science." After one year at Oglethorpe
and five years at his alma mater, Athens, Georgia, he accepted the pro-
fessorship of Chemistry and Geology at South Carolina College, Colum-
bia, South Carolina, which position he held until the end of the Civil

^ Soon after the death of Professor Le Coute the preparation of his memoir was under-
taken by Dr. W J McOoc. The mullipjicily of his duties prevented immediate writing
and llie matter was long delayed, and his illness caused further delay and liiial failure.
Then the change in the Secretaryship of the Society diverted attention from the matter.

■•=The Autohlography of Joseph Le Conte. D. Appleton & Co. lOO.'J.

3 The writer is specially indel)led to the memoir by S. B. Christy, in the Trans. Am.
Inst. Mining Engineers, from which the quoted matter In the present writing is mostly
taken.

48 PROCEEDINGS OF THE PHILADELPHIA MEETING

War. Like many others, he was forced against his judgment and desire
to join the forces of secession. He was employed as geologic expert in
search for niter deposits and as chemist in the manufacture of medicines
and explosives. Probably the most interesting part of his autobiography
is that relating to the Civil War, with the story of his experiences during
the war and the succeeding period of reconstruction. Becoming discour-
aged with the conditions in the South, he and his brother John success-
fully applied for positions in the new University of California, and began
work there in 1869, teaching botany, zoolog}', and geology, without as-
sistance or laboratory appliances,

Le Conte was a tine representative of the older group of eminent geolo-
gists who were self-taught and with knowledge in many departments of
science. The breadth of his interest is shown by an analysis of his list
of writings, which, as given in Christy's memoir, has 311 titles. Ex-
cluding repetitions or duplicate publication, the number is about 300,
Of these geology includes only 57, philosophy 48, physics (mostly optics)
48, biology and medicine 16, education 10, biography 6, zoology 4, soci-
ology and travel 3 each, and 5 unclassified, A corrected list of his writ-
ings in geology is here appended, making 63 titles, not including the
revisions of his text-books.

That Le Conte's mind was of the philosophic type rather than the
scientific is shown not only by the wide variety and deductive character
of his writings, but also by the fact that he is probably better known to
the general public through his jihilosophic essays, chiefly on evolution,
than by his geologic work. His Elements of Geolog}% issued in 1878,
was for many years probably the most popular American treatise on the.
science and gave him his public reputation as a geologist. His favorite
theme in geology, origin of the continents and formation of mountains,
testifies to the philosophic bent of his mind. One of his first papers, in
1859 (fifth in the appended list), was on continent formation, and his
residence after 1869 in California greatly stimulated this line of thought.
At least one-third of all the titles in the list falls into geophysics. While
he was fond of life in the open and made several trips in the Cordilleras,
recording important observations, he was not an enthusiastic field student,
and his record of facts of observation is not large. If he had remained
during his life in South Carolina, it seems more than possible that his
philosophic bent might have kept him from reaching eminence in geology ;
but, being transplanted to the Cordilleran region, his geologic interest
was inevitable. The genesis of the Sierras and diastrophism were at-
tractive subjects for his keen intellect. Concerning his intellectual tastes,
he writes in his autobiography (pages 385-386, 387-388) :

MEMOIK OF JOSEPH LE CONTE 49

"Until I was thirty I could not have said whether my tastes were more in
the direction of science or of art or of philosophy. Circumstances turned me
mainly in the direction of science, but I could never be a specialist in the
narrow sense of the term. My writings and my thoughts, lilie my education,
have been in many directions." . . . "Yet some of my heartiest and most
valued friends think that my reputation hereafter will be more philosophic
than scientific. It may be so, for even my science is not special in the nari'ow
sense, but is rather a sort of philosophic science, dealing mainly with larger
questions. The domains of science and pliilosophy are not separated by hard
and fast lines ; they largely overlap ; and it is in this border land that I love
to dwell."

Any one who may be interested in Le Contc's views on geo])liysical
problems will find them cry\stallized in the Elements of Geology, and with
fuller presentation in three papers : his presidential address before the
American Association for the Advancement of Science, at the Madison
meeting, 1893 ;* his address as retiring President of this Society, at its
eighth summer meeting, at Buffalo, 1896,^ and in his memoir of Dana.'^

Like all students of earth science of his and previous time, his geo-
physical philosophy was founded on the conception of a globe cooling
from incandescence. If we abandon the hypothesis of an originally liquid
globe, as quite certainly we must, much of the Avritings of Le Conte and
Dana will have only an historic and academic interest; but a brief state-
ment of their views, based on the Laplacian hypothesis, may be of some
interest if placed alongside those of Chamberlin, based on the planetesimal
hypothesis.

In his presidential address Le Conte recognized four classes of earth-
crust movements, in the following order of greatness :

"(1) Those greatest, most extensive, and probably primitive movements by
which ocean basins and continental masses were first differentiated and after-
ward developed to their present condition; (2) Those movements by lateral
thrust by which mountain ranges were formed and continued to grow until
l)alanced by exterior erosive forces; (3) Certain movements over large areas,
but not continuous in one direction, and therefore not indefinitely cumulative
like the two preceding, but oscillatory, first in one direction, then in another,
now upward and then downward; (4) Movements by gravitative readjustment,
determined by transfer of load from one place to another. . . .

"Of these four kinds and grades of movement the first two are primary and
continuous in the same direction, and therefore cumulative, until balanced by
leveling agencies. The other two, on the contrary, are not necessarily con-
tinuous in the same direction, but oscillatory. They are, moreover, secondary.

*Proc. Am. Assoc. Adv. Sci.. vol. 42, l.SO."!, pp. 1 '_'" ; .Tour. (JpoI., vol. 1, isn:*.. pp.
^.42-.'57.^.

»BuII. Oool. Koc .\m., vol. S. ISO?, pp. IK: 12fi.

•Bull, Gcol, Soc. Am,, vol. 7, ISO,''., p[.. 40.1 474.

50 PROCEEDINGS OF THE PHILADELPHIA MEETING

and are imposed on the otluM- two or primary movements as modifying, ob-
scuring, and often completely masking their effects."

According U) iJaiia's coiircpLion, the solidification of tlie globe was first
at the center. The investing liquid arranged itself in layers of increas-
ing density downward from the surface to the solid nucleus. Certain
areas of the surface became crusted earlier than the general surface.
Becoming heavier by solidification than surrounding mass, the solid crust
sank, and was replaced by inflow of the lighter superficial fluid, which
in turn solidified and sank. The result was to build up from the solid
nucleus below a lighter, solid mass that constituted the primitive con-
tinent. The less rapidly crusting areas, of denser materials, formed the
oceanic areas. (Le Conte's Geological Society address, page 118.) Le
Conte's theory did not emphasize the conditions and effects of the super-
ficial crusting as did Dana's, but assumed area! differences in density and
iiiiiductivity.

"If, then, over some large areas the matter of the earth were denser and
more conductive than over other large areas, the former areas, by reason of
thoir greater density alone, would sink below the mean level and form hollows;
for even in a solid — much more in a semi-liquid, as the earth was at that
time — there must have been static equilibrium (isostasy) between such large
areas. This would be the beginning of oceanic basins ; but the Inequalities
from this cause alone would probably be very small but for the concurrence
of another and much greater cause, viz., the greater conductivity of the same
areas. Conductivity Is not, indeed, strictly proportional to density ; but in a
general way it is so. It is certain, therefore, that the denser areas would be
also the more conductive, and therefore the more rapidly cooling and con-
tracting areas. This would increase, and in this case progressively increase
the depression of these areas.

"The two causes — density and conductivity, isostasy and contraction — would
(•(incur, but the latter would be far the greater, because indefinitely cumulative.
The originally evenly spheroidal lithosphere would thus be deformed or dis-
torted, and the distortion, fixed by solidification, would be continually increased
until now." (Address, page 116.)

This idea of Dana, that the continental areas were the first to solidify
and the oceanic areas subsequently, was accepted by Le Conte and applied
in harmony with his own thought as follows :

". . . But a little reflection will show that these two facts, namely, the
earlier crusting of the land areas and the more rapid cooling and contraction
of the ocean areas, are not inconsistent with one another; for the more con-
ductive and rapidly cooling areas would really be the last to crust, because
surface solidification would be delayed by the easy transference of heat from
below, wliile the less conductive land areas would certainly be the first to
crust, because the non-conductivity of those areas would prevent the access
of heat from below."

MEMOIR OF J OSEPH LE CONTE 51

The hypothesis assumes sufficient heterogeneity of composition of the
globe and unequal density as the causes initiating the greater subsidence
of the oceanic areas, and unequal heat conductivity and static equilibrium
as the conditions necessary to progressively increase the surface relief.
As a corollary to this, it follows that the continental masses and the
oceanic depressions are permanent features, as taught by Dana.

The original heterogeneity, in efficient degree, would seem improbable
in a rotating globe built from superheated gaseous material commingling
and diffusing through long eons of time. This objection Le Conte met
by claiming that the efficient differences in density and conductivity were
very small and the resultant surface relief of the globe comparatively
insignificant. It is impossible to confidently contradict the assumption,
but it would seem as if the heterogeneity in a sphere of superheated
matter would not be represented by such large unit areas as the present
continents and oceans.

According to the planetesimal hypothesis, the planet was slowly built
by accretion of cold particles and was always solid and always cold at the
surface. Whatever heterogeneity and irregularity of figure was produced
by unequal infall of the planetesinials, or by differences in their com-
position, could not be destroyed by liquid convection and diffusion ; but
original heterogeneity is not an important factor under this conception.
Professor Chamberlin postulates only such slight inequality or small de-
pressions in the surface of the embryo planet as would contain the shallow
waters of the primitive ocean. The exposed areas, subjected to weather-
ing processes, became relatively lighter in weight, while the suboceanic
areas, by protection from weathering and by concentration, became su-
perior in density. This difference in specific gravity of large areas by
epigone processes began when the growing globe was small, probably
smaller than the planet Mars, or as soon as it was able to retain its
atmosphere and hydrosphere; and the differential density and surface
relief has been perpetuated to the present time. Isostatic equilibrium
and comparative permanence of the continental masses follows under this
hypothesis the same as under the Laplacian.

The contraction of the earth's crust as an effect of interior cooling and
shrinkage has been the subject of philosophic discussion since its recog-
nition by Descartes in 1644; but the first description and mapping of
extensive folding of strata in actual demonstration of great horizontal
compression was by the Kogers brothers, about IfilO, in their Appalachian
sections in Virginia and Pennsylvania, .\inerican geologists, and par-
ticularly Dana and Lo Conte, wore sndi active supporters of fhe con-
tractional theoi7 of mountain fnniKilion that it lias sometimes been called

52 PROCEEDINGS OF THE PHILADELPHIA MEETING

the American theory. As a topic of geologic philosophy, dealing with
such vast elements of force, time, and mass, it was naturally attractive
to Le Conte, and formed the subject of his important official addresses.
While he perhaps did not add any original element to the theory, he gave
such clear analysis and attractive presentation of the arguments for
genesis of mountains by compression of areas, weakened by thick sedi-
mentation, that he must stand with Dana as a chief expounder.

We now accept as fact the horizontal crushing of thick strata in the
production of the great mountains, but the efficient cause of extensive
compression is still a subject of study. Under the Laplacian hypothesis
the primary cause is the cooling of the superheated interior ; but, accord-
ing to physical laws and mathematical calculations, the radial contraction
produced by any possible loss of heat since C'ambrian time can account
for only a veiy small part of the superficial shortening. The amount of
contraction of the circumference of the globe in 100,000,000 years, due
to the greatest cooling thought possible, is about 10 miles, which is less
than the amount of compression represented by any one of the great
mountain systems. The circumferential shortening on any great circle
of the globe since Cambrian time can not be less than 100 miles.

Under the planetesimal hypothesis the shrinkage of the planet is due
to increase of density.

"The heat of the earth is supposed to have been developed chiefly by re-
duction of volume and by radio-activity, and the heat thus developed is one
of the forces which check further decrease of volume. Loss of heat is, of
course, a cause of shrinkage, but its effect is thought to be less than that of
molecular and sub-molecular rearrangements of the material of the earth,
resulting in greater density. The loss indeed may not be greater than the new
heat generated in the shrinkage." '

It is estimated that to produce the circumferential shortening of 100
miles would require a radial shortening of 16 miles.^ This seems im-
possible from mere loss of heat during recorded geologic time, but possible
by condensation of a porous globe built up by infall of cold matter. As
the hydrosphere and atmosphere are chiefly matter expelled from the
earth's interior, they represent reduction of volume, and some reduction
during post-Cambrian time may be credited to that cause.

Concerning oscillatory or diastrophic movements, Le Conte, after giv-
ing the proofs of such great down-and-up movements in certain areas,
like the Colorado plateau, wrote as follows :

"It must be confessed that the cause of these oscillatory movements is the
most inexplicable problem in geology. Not the slightest glimmer of light has

^ Chamberlin and Salisbury's lutroductory Geology, p. 225.
* The same, p. 224.

]\rEMOiR OF ,tosp:ph le c'Onte 53

yet been shed on it. I bring forward the problem here, not to solve it, for I
confess my inability, but to differentiate it from other problems, and especially
to draw attention to these movements as modifying the effects of movements
of the first kind, and often so greatly modifying them as to obscure the prin-
ciple of the permanency of oceanic basins and continental areas, and even to
cause many to deny its truth. Nearly all the changes in physical geography
in geological times, with their consequent changes in climate and in the char-
acter and distribution of organic forms — in fact, nearly all the details of the
history of the earth — have been determined by these oscillatory movements ;

This pheuoineiiun still awaits satisfactory analysis and soluiioii, but is
better explained under the planetesimal hypothesis, since this admits of
much greater contraction of the globe and of consequent crowding and
crushing of the small continental segments between the larger oceanic
segments, with consequent warping and buckling of large surface areas,
specially along the continental margins, under pressures varying in di-
rection and degree.

In his autobiography Le Conte has given his own estimate of his con-
tribution to the world of thought. He seemed to take the most pride in
his writings on evolution. His best original work was probably in optics.
Concerning geology, we give his own words :

"In geology, T believe some real substantial advance in science was made
in my series of papers: (1) on the structure and origin of mountain ranges;
(2) on the genesis of metalliferous veins; (.3) especially in that on critical
periods in the history of the earth; (4) on the demonstration of the Ozarkian,
or better, the Sierran epoch, as one of great importance in the history of the
earth, I might mention several others that I believe are of prime importance,
but I am willing to stand by these."

A suitable close for this memoir is the fine tribute bv Professor
Chamberlin.^"

"With the death of Dr. Joseph Le Conte there has passed away perhaps the
hist distinguished representative of the general geologist as typified during
the past century. This passing type of the general geologist was a distinctive
outgrowth and representative of a transitional stage of intellectual procedure — -
a passage from the former mode in which the generalizing and philosophical
factors held precedence and the toilsome modes of scientific verification fol-
lowed as their servitors, to the present or at least the coming method in which
scientific determinations are the basal factors to which generalizations and
philosophies are but dependent accessories. Wo owe much of the transition
itself to Dana and Le Conte, the two noblest American representatives of the
passing type, for while they grew u]) under the influence of the older intel-
lectual attitude, they grew out of if in spirit while (lioy steadied and guided

" I'.illl. fii'ol. Hoc. Ani,, vol. S, p. \22.

1" RdKorial in .Toiirnal of Geology, vol. 0, inoi, pp. -l."?!) 1 l(t.

V — Bull. Gkol. Soc. Am., Vol. 20, ini4

54 PROCEEDINGS OF THE PHILADELrHIA MEETING

the transition. They were distinctively students of geology in the special
sense in which that term implies the organized doctrine of the earth, rather
than students of what might be termed gcics, the immediate study of the earth
itself in the field and laboratory. They were preeminently students of the
accumulated data and of the literature of the science, with generalization and
philosophic inference as their dominant inspiration. Neither Dana nor I^e
Conte were eminently field students ; much less wore they specialists in a
chosen field of the broad geological domain. Their point of view was that of
the organizer and of the philosopher, and the contribution they made in their
chosen sphere was indispensable and immeasurably valuable. . . . None
the less, the philosophical factors and the philosophical point of view are in-
dispensable if the science is to make its most wholesome progress, and we owe
to Le Conte and to those he typifies an immeasurable debt, for they have kept
us in fresh touch with the generalizations and the philosophy of the science,
and have inspired us with their own contributions to the broader conceptions
of geology and of its relation to kindred sciences. The writings of Le Conte
are graced by the fruits of wide learning, a lucid style, a genial attitude, and
a candor that has called forth universal love and admiration."

Oil llic [)la(C<)rjn TiC r'oiitc was a pici iirosque fij2,'ui"o. TTis P'rciicli
descent was evident in his vivaoioiis and soniowhat eiiiolioiial manner,
with a high-pitched hnt clear and resonant voice, modnlaied to every
phase of his theme. In both speech and writings he had naivete, with
self-confidence, but without self-conceit. Had he chosen the pnlpit or
politics or the stage as his profession, he would undoubtedly have become
famous in either calling. He was universally admired and loved. To
his students he was "Professor Jo." The Le Conta Memorial Lodge
(plate 6), built by the Sierra Club at the foot of Glacier Point, near
where he died, is a monument to his memory and a testimony of high
regard. The story of his active life may be read in his autobiogi'aphy,
'^ . . written with all the frankness of the Confessions of Kousseau,
it depicts a noble character witliout a trace of morbid self-consciousness,
breathes a high philosopliic spirit, and is enlivened with a fine sense of
humor."

BIBLIOGRAPHY *

1853. Salt lakes. Ga. Univ. Mag. April, 1853.

1857. On the agency of the Gulf Stream in the formation of the peninsula of

Florida. Am. Assoc. Adv. Sci., Proc, vol. 10, pt. 2, pp. 103-119; Am.
Jour. Sci. (2), vol. 23. pp. 46-60.
Geology in a course of education. Inaugural address at S. C College.

1858. Three lectures on coal. Smith. Inst. Rept. for 1857, pp. 119-168.

1859. Theory of formation of continents. Canadian Nat., vol. 4, p. 293.
1872. A theory of the formation of the great features of the earth's surface.

Am. Jour. Sci. (3), vol. 4, pp. 345-355, 460-472.

1 This Is a Ust of only his geologic writings. — H. L. F.

BIBLIOGRAPHY OF JOSEPH LE CONTE 55

1S73. On some of the ancient glaciers of tlie Sierras. Am. Jour. Sci. (3),
vol. 5, pp. 325-342 ; Cal. Acad. Sci., Proc, vol. 4, pp. 259-262.
On the formation of the features of the earth's surface. Reply to criti-
cisms of T. Sterry Hunt. Am. Jour. Sci. (3), vol. 5, pp. 448-453.

1874. On the great lava flood of the west and on the structure and age of the

Cascade Mountains. Am. Jour. Sci. (3), vol. 7, pp. 167-180, 259-267;
Cal. Acad. Sci., Proc, vol. 5, pp. 214-220.

1875. On some of the ancient glaciers of the Sierras. Am. .Tour. Sci. (3),

vol. 10, pp. 126-139 ; Cal. Acad. Sci., Proc, vol. 6, pp. 38-48.
Geology of New Mexico, Remarks on. Phila. Acad. Sci., Proc, vol. 27,
pp. 267-268.

1876. On the evidences of horizontal crushing in the formation of the coast

range of California. Am. Jour. Sci. (3), vol. 11, pp. 297-304.

1877. On the critical periods in the history of the earth and their relation to

evolution ; on the Quaternary as such a period. Am. Nat., vol. 11,
pp. 540-557; Kansas City Review, vol. 1, pp. 477-483, 522-530; Am.
Jour. Sci. (3), vol. 14, pp. 99-114.
Prairie mounds. Nature, vol. 15, pp. 530-531.

1878. Elements of geology. A text-book for colleges and for the genei-al

reader, xiii -j- 588 pp. 8". New York. Fourth edition. 1896.
Geological climate and geological time. Nature, vol. 18. pp. 668.
On the structure and origin of mountains, with special reference to

recent objections to the contractional theory. Am. Jour. Sci. (3),

vol. 16, pp. 95-112.

1879. On the extinct volcanoes about Lake Mono and their relation to the

glacial drift. Am. Jour. Sci. (3), vol. 18, pp. 35-44.

1880. Coral reefs and islands. Nature, vol. 22, pp. 558-559.

The old river beds of California. Am. .Tour. Sci. (3), vol. 19, pp. 176-
190.

1881. Geology of California, in Phelps, A. Contemp. Biog., vol. 1, p. 290.

1882. Rate of denudation. Geol. Mag., vol. 9, p. 289.

Origin of jointed structure in undisturbed clay and marl deposits. Am.

.Tour. Sci. (3), vol. 23, pp. 2,3.3-234.
Judd on volcanoes, Notice of. Californian, vol. 5, p. 85.
The phenomena of mineral vein formation now in progress at Sul])liur

Bank, California, with "W. B. Rising. Am. .Tour. Sci. (3), vol. 24,

pp. 23-33.

1883. Car.son foot-prints. Cal. Acad. Sci., Bull. (?). Nature, vol. 28, pp.

101-102.
On the mineral vein formation now in progress at Steamboat Springs

compared with the same at Sulphur Bank. Am. Jour. Sci. (3), vol.

25, pp. 424-428.
Genesis of metalliferous veins. Am. .Tour. Sci. (3), vol. 26. pp. 1-19.
The reefs, keys, and peninsula of Florida. Science, vol. 2. p. 764.
Continent formation. Geol. Mag., vol. 10 (11), pp. 523-524.

1884. A compend of geology. 399 pp. 12°. New York.

Elevation and subsidence of earth crust. Nature, vol. 29, pp. 212-213.
The IT. S. Geological Siu'voy ; review of the second ;in<l tliird reports.
Science, vol. 4, pp. 62-71.

56 PROCEEDINGS OF THE PHILADELPHIA MEETING

1885. Earthquake shocks more violent on the surface than in mines. Science,

vol. 6, pp. 540.
Review of "Paradise Found." Science, vol. 5, pp. 406-407.

1886. On the permanence of continents and ocean basins, with special refer-

ence to the formation and development of the North American con-
tinent. Geol. Mag., vol. 3 (.3), pp. 97-101.

I'ost-Tertiarj- elevation of the Sierra Nevada, shown by the river beds.
Am. Jour. Sci. (3), vol. 32, pp. 167-181.

The development of the North American continent. Geol. Mag., vol. 3
(3), pp. 287-288.

1887. Determination of the depth of earthquakes. Science, vol. 10, pp. 22-24.
The flora of the coast islands of California in relation to recent changes

of ph3sical geography. Am. Jour. Sci. (3), vol. .34, pp. 4.'57-460; Cal.
Acad. Sci., Bull., vol. 2. pp. 515-520 ; Am. Geol., vol. 1, pp. 76-81.

1888. Mountain formation. Letter to the Philos. Mag., vol. 25, pp. 450-451.
Glacial motion. Letter to the Philos. Mag., vol. 25, p. 452.
Nomenclature, etc., of eruptives, . . . life of the Archean, and on the

nomenclature of the Lower Paleozoic. Inter. Geol. Cong.. Am. Com-
mittee Reports, 1888, A, pp. 55-57.

On nomenclature of Cenozoic formations. Inter. Geol. Cong., Am. Com-
mittee Reports, 1888, F. pp. if -18; Am. Geol., vol. 2, pp. 283-284.

Oil the use of the term "Taconic" Inter. Geol. Cong.. .\m. Committee
Reports, 1888, B, p. 17; Am. Geol., vol. 2, p. 207.

1889. The general interior condition of the earth. Am. Geol., vol. 4, pp. 38-

44.

On the origin of normal faults and of the structure of the basin range.
Am. Jour. Sci. (3), vol. 38, pp. 257-263.
1891. Tertiary and post-Tertiary changes of the Atlantic and Pacific coasts,
with a note on the mutual relations of laud-elevation and ice-accumu-
lation during the Quaternary period. Bull. Geol. Soc. Am., vol. 2,
pp. 323-330.

Address of welcome to the International Geological Congress, at Wash-
ington. I). C. 1891. Inter. (Jeol. Cong.. Compte Rendu, 1893, pp. 5.3-56.
1893. Theories of the origin of mountain ranges. Am. Assoc. AdA'. Sci., Proc.
vol. 42, pp. 1-27 ; Jour. Geol., vol. 1, pp. 542-573 ; Sci. Am. Suppl., vol.
36, pp. 14768-14769, 14776-14778.
1895, The genesis of ore deposits. (Discussion of paper by F. Posepuy. )
Am. Inst. Min. Eng.. Trans., vol. 24. pp. 996-1006.

Causes of the Gulf Stream. Science, vol. 2, pp. 188-189.

Critical periods in the history of the earth. Univ. of Cal., Dept. Geol.
Bull., vol. 1, pp. 313-336 ; Am. Geol., vol. 16, pp. 317-818.

Review of Dana's Manual of Geology. Science, vol. 1, pp. 548-550.

Memoir of James D. Dana. Bull. Geol. Soc. Am., vol. 7, pp. 461-474.

1897. Earth-crust movements and their causes. Bull. Geol. Soc. Am., vol. 8,

pp. 113-126 ; Science, vol. 5, pp. 321-330.

1898. Contribution to "a symposium on the classification and nomenclature

of geologic time divisions." Jour. Geol., vol. 6, pp. 337-338.
The origin of transverse mountain valleys and some glacial phenomena
in those of the Sierra Nevada. Univ. Chronicle, vol. 1, pp. 479-497.

BIBLIOGRAPHY OF JOSEPH LE CONTE 57

1899. The Ozarkian and its siguificance in theoretical geology. Jour. Geol.,

vol. 7, pp. 525-544.
1!»(X). A century of geology. Pop. Sci. Month., vol. 56, pp. 431-443, 546-556:
Smith. Inst. Ann. Kept, for 1900, pp. 265-287.
Journal of ramblings in the high Sierra. Sierra Club, Bull., vol. 3,

pp. (?).
An early geological excursion. Science, vol. 11, p. 221.

The reports of committees were then called fur. 'i'liese were submitted
as follows:

REPORT OF THE COMMITTEE ON PHOTOGRAPHS

Our collection of photographs is now stored in my office in the U. S.
CTBological Survey, where it is convenient for access. jSTo new material
has been received for many years, and of late it has not been utilized to
any great extent.

N. H. Barton,

Committee. .

REPORT OF THE COMMITTEE ON GEOLOGICAL NOMENCLATURE

Tlie Secretary, Arthur Keith, reported that no communications regard-
ing names for geological formations had been received by the committee
during the year, and that the committee asked to be discharged, inasmuch
as for several years there had been no communications addressed to it.

On motion, this report was accepted and the committee was discon-
tinued.

On motion, the Secretary was instructed' to send a telegram of sym-
pathy in bis illness to President Becker.^

After listening to several announcements regarding the program for
the meeting, the Society proceeded to tlie consideration of scientific
papers.

1 The following telegram was sent :

Geological Society directs nie to send you its cordial groetings and its regrets that
lllnpss prevents your pi'i'ScniM' at its twciily-si'vciil li annual meeting.

(Signcil) 10dm irND Otis IIovky,

Secretary,
On Wednesday the fiilluwinK ri-p'.v was lecelvi'd by letti'i- :

Dkau Mr. Skciiktakv : I am grateful to the Geological Society for its sympathetic
good wishes. Fortunately I feel sure of the succt-ss i»f llic meeting, mueli as I should
have lilted an opportunity to conlrlbntt' to It.
Cordially yours,
(Signed) GKORGn F. P.kckkr.

I'resiilent.

58 PROCEEDINGS OF THE PHILADELPHIA MEETING

TITLES AND ABSTRACTS OF PAPERS PRESENTED IN GENERAL SESSION AND

DISCUSSIONS THEREON

RELATION OP BACTERIA TO DEPOSITION OF CALCIUM CARBONATE

BY KARL F. KELLEKMAN ^

(Ahstract)

At the suggestion of Dr. T. Wayland Vaughan, bacterial studies of water
and bottom mud from the Great Salt Lake and sea-water and bottom deposits
from the vicinity of Florida and the Bahamas were undertaken in the hope
of supplementing the work of Vaughan,= of Drew,^ and of Dole* in regard to
the probable agencies concerned in the precipitation of calcium carbonate and
the formation of oolites.

It has been possible to form calcium carbonate by the action of bacteria on
various soluble salts of calcium, both in natural waters and in synthetic
mixtures. The most important natural precipitation is probably the trans-
formation of calcium carbonate by the combined action of ammonia, produced
by bacteria either by the denitrification of nitrates or by the fermentation of
protein, together with carbon dioxide, produced either by the respiration of
large organisms or the fermentation of carbohydrates by bacteria. Both ordi-
nary crystals of calcium carbonate and oolites may be produced by the growth
of mixed cultures of bacteria, either in salt or fresh water. The zonal struc-
ture of the oolites of bacterial origin and of those found in nature in oolitic
deposits appears to be exactly the same ; undoubtedly this shows the similarity
of the processes of their origin.

Eead in full from manuscript.

CORAL REEFS AND REEF CORALS OF THE SOUTHEASTERN UNITED STATES,
THEIR GEOLOGIC HISTORY AND SIGNIFICANCE

BY THOMAS WAYLAND VAUGHAN

(Abstract)

After briefly alluding to some of the more recent publications on coral reefs,
the author stated what in his opinion were the necessary lines of investigation
in order to understand the ecologic factors influencing coral-reef development,
the constructional role of corals and other agents, and the series of geologic
events which preceded any particular coral-reef development. The geologic
history of the extensive coral reefs of the southeastern United States and
near-by West Indian islands, which have been the subject of investigation for
a number of years, was outlined, and the bearing they have on the theory of
coral-reef formation was indicated.

The author stated his conclusions regarding the Florida coral reefs as fol-

1 Introduced by T. Wayland Vaughan.

2 T. W. Vaughan : Bull. Geol. Soc. Am., vol. 25, No. 1, p. 59. March, 1914. Also
Publication No. 182, Carnegie Inst, of Washington, pp. 49-67.

=* G. H. Drew : Publication No. 182, Carnegie Inst, of Washington, pp. 1-45.
* R. B. Dole : Publication No. 182, Carnegie Inst, of Washington, pp. 69-78.

ABSTRACTS OF PAPERS 59

lows: (1) Corals have played a subordinate part, usually a negligible part, in
the building of the Floridian plateau; (2) every conspicuous development of
coral reefs or reef corals took place during subsidence; (3) in every instance
the coral reefs or reef corals have developed ou platform basements - which
owe their origin to geologic agencies other than those dependent on the pres-
ence of corals.

The older Tertiary reefs and reef corals of Saint Bartholomew, Antigua,
and Anguilla all grew on subsiding basements. The relatively small propor-
tion of the contribution by corals to calcareous sediments in Florida, the
Bahamas, and the West Indies was shown.

It was shown that the Floridian plateau was similar in configuration to the
Mo.squito bank off Nicaragua, to Campeche bank off Yucatan, and to Georges
bank oft" Massachusetts; the east side of the Floridian plateau is similar to
the continental shelf off Cape Hatteras. The platform which supports the
leef along the east coast of Florida extends beyond the reef limits northward
of Fowey Rock. The reef platform of the Great Barrier Reef of Australia is
similar to the continental shelf of eastern North and Central America, and it
continues south of the reef limits. Rosalind Bank, Caribbean Sea, was com-
pared with Rangiroa, Paumotus, which is similar in essential features. The
complex history of the coral-reef foundations in Florida, Antigua, Saint
Martin, Anguilla, and Bermuda was described, and it was stated that the
formation of the platforms could not be referred solely to Pleistocene time.

Attention was directed to the facts that around the Island of Saba, in which
volcanic activity has so recently ceased that the crater is still preserved, there
was scarcely any platform at all ; that in the case of the young but slightly
older volcanic island of Saint Kitts, the platform was narrow, while the geo-
logically much older islands standing above the Antigua-Barbuda bank, the
Saint Martin plateau, and the Virgin bank rise above platforms which are
miles across and have an area many times greater than that of the present
land surfaces. Width of platform is therefoi'e indicative not of the amount of
submergence, but of the stage attained by planation processes.

The conclusions were summarized as follows :

1. Critical investigations of corals as constructional geologic agents are
bringing constantly increasing proof that they are not so important as was
long believed, and that many of the phenomena formerly attributed to them
must be accounted for by other agencies. Here it should be emphasized that
the ecology of probably no other group of marine organisms is known nearly
so thoroughly as that of corals.

U. All known modern offsliore reefs which have been investigated gi'ow on
platforms which have been submerged in Recent geologic time.

3. No evidence has as yet been presented to show that any barrier reef
began to form as a fringing reef ou a sloping shore and was converted into a
barrier by snlisidi-iicc ; Itut It is dear that many, if not all, barrier reefs stand
ou marginal plaLl'urms which alieady existed previous to Recent submergence
and the formation of the modern reefs.

4. Study of the geologic history of coral-icrf i)I:itforms has estiddished tliat
there were platforms in early Tertiary time on the site of m:\uy of the present-
day platforms, and evidence has not as yet been adduciHl to ]lro^■e long -con-
tinuetl, uninterrupted subsidence in any coral-reef area. There have been
many oscillations of sealevel and Recent submergence is |>i<>l.alp!y lonipHcated

60 PROCEEDINGS OF THE PHILADELPHIA MEETING

in many areas by differential crustal movement concomitant witti increase in
volume of oceanic water through deglaciatlou.

5. The width of a submerged platform bordering a laud area is indicative
not of the amount of submergence, but of the stage attained by planation
processes. Other conditions being similar, the longer the period of activity o^
such processes, the wider will be the platform.

6. The principal value of the coral-reef investigation to geology consists not
so much in what has been found out aboui corals as in the study of a complex
of geologic phenomena, among which coral reefs are only a conspicuous in-
cident.

Read in abstract from manuscript.

Discussion

Dr. Wayland T. Vaugiian, in reply to tlie question of Doctor Pilsbry as to
tiie signihcance of the Funa Futi Ijoiiug, stated tliat, because of inadequate
Ivuowledge of the stratigraphic distribution of the organisms encountered in
the bore hole, the geologic age of the formation penetrated could not now be
determined. He also stated that there were certain features of Funa Futi
which indicated that there had probably been oscillations of sealevel.

Prof. A. W. Geabau : Louis Agassiz in one of his early letters speaks of the
imix)rtance of coralline algae in the formation of reefs at Florida. He con-
sidered the nullipores more important than the corals in this connection.

Doctor Vaughan, in reply to Professor Grabau's remarks concerning the
constructional role of coralline algae along the Florida reef, stated that the
coralline alga*, in his opinion, were subordinate in importance to corals, al-
though they contribute relatively large amounts of calcium carbonate to the
sea-bottom along the reef tract. In the shoal waters of southern Florida and
the Bahamas bacteria are the most important agency whereby calcium car-
bonate is taken from the sea-water. The others, rated according to importance,
are probably (1) foraminifera, (2) mollusks, (3) corals, and (4) coralline
algae.

CAUSES PRODUCING SCRATCHED, IMPRESSED, FRACTURED, AND RECEMENTED
PEBBLES IN ANCIENT CONGLOMERATES

BY JOHN M. CLABKE

(Abstract)

The Devonian conglomerate lying beneath the fish-beds of Migonasha, Prov-
ince of Quebec, is a characteristic "Nagelfluh" filled with scratched, fractured,
and deeply impressed pebbles. Specimens exhibited indicate that the explana-
tion of the phenomena of impression by solution, as suggested by Sorby, Heim,
Kayser, and others, is inadequate, and that the effects described are in large
part actually due to forcible contact resulting from internal friction. Some
of the pebbles show unqualified evidence of glacial scratching, and the entire
mass is regarded as an outwash from glacial moraine.

Presented in full from manuscript.

ABSTRACTS OF PAPERS 61

Discussion

Dr. A. W. Gkabau: The last illustration shown resembles veiy closely the
Nagelfluh of Salzburg — a fluvio-glacial deposit of late IMeistocene origin — and
Doctor Clarke's comparison of these Devonic deposits with the Nagelfluh
seems a very happy one. I would ask Doctor Clarke if indications of chatter
marks, such as are common on the pebbles of the Old Red, are found in the
pebbles of the Scaumenac region.

Doctor Clarke replied that he did nut think chatter marks were evident on
these blocks.

The Society adjourned al)Out 12.20 o'clock and reconvened in sections
at 2.30 o'clock.

TITLES AND ABSTRACTS OF PAPERS PRESENTED BEFORE THE FIRST SECTION

AND DISCUSSIONS THEREON

The first section met, with Vice-President Horace B. Patton as pre-
siding officer and E. 0. Hovey as Secretary, and took up the papers
entered in the printed program under Group A: Dynamic, Structural,
Glacial, Physiographic.

ORIGIN OF THE FED BEDS OF WESTERN WYOMING
BY E. B. BRANSON

{Abst7~act)

The Red Beds of western Wyoming are about 1,400 feet in thickness along
the western outcrops and thin eastward. Eight hundred and ninety feet from
the bottom they contain a formation, 40 to 60 feet thick, which is plainly of
subaerial origin. Some 200 feet above this a highly cross-bedded sandstone
about 60 feet thick seems to have originated from wind-blown materials. Near
the top are extensive beds of gypsum up to 40 or .50 feet in thickness. All of
the Red Beds in western Wyoming, excepting the subaerial formations above
mentioned, seem to have been marine in origin, the evidence being : wide-spread
deposition of gypsum, beds of sandstone of uniform thickness composed of
uniform materials extending over wide areas, and with wide-spread ripple-
markings on horizontal surfaces. The gypsum can not be a deposit from fresh
water in inland basins, because no other carbonates are deposited or occur with
the gypsum, because of the rarity of sedimentary impurities, because of the
absence of sodium ehlorid(! and other salts, because of the excessive time re-
quired for deposition. There are no evidences of erosion of the near-lying
rocks during the time when the gypsum was being deposited.

I»ead in I'lill frdiii iiiaiiiiscript.

Discussion

I'rof. A. W. Grahau : I would question the interpretation ()f any i)art of the
Kcd I'.cds us of marine origin. The absence of positive indications of subaerial

62 PROCEEDINGS OF THE PHILADELPHIA MEETING

origin, sucli as mud cracks, cross-bedding, etcetera, is not necessary evidence
against tlie continental origin of such deposit. Tliey may be river floodplains
or playa deposits. The absence of marine organisms is far more significant.

Doctor Branson replied : When the deposition of the Red Beds began waters
were probably already highly concentrated and unfavorable for life, and the
increasing salinity of the waters may have soon rendered the interior seas
uninhabitable for most forms of life, and on this account fossils would be few
or entirely lacking in the deposits. That such increasing salinity came about
is evidenced by the increase of lime in the sandstone from the bottom toward
the top, by the limestone deposits at the SOO-foot level, and by the gypsum de-
posits near the top.

Prof. H. E. Gregory took the chair at 2.55 o'ehick.

NEW POINTS ON THE ORIGIN OF DOLOMITES
BY FRANCIS M. VAN TUYL ^

(Ahstract)

A careful study of the dolomites of the upper Mississippi Valley was under-
taken for the Iowa Geological Survey during the field season of 1912. More
recently a grant from the Esther Herrmun Research Fund of the New York
Academy of Sciences has made possible much more extensive studies of the
dolomitic limestones of the Eastern and Central States. The present prelimi-
nary paper is intended merely to set forth some of the more important results
of these studies.

Existing theories of the origin of dolomite were briefly considered, after which
the problem was attacked from three standpoints, namely, the experimental
evidence, the field evidence, and the petrogra])hic evidence. The conclusion
was reached that the great majority of the dolomites, ranging in age from the
Cambrian to the present, have resulted from the replacement of limestones
before they emerged from the sea. The replacement need not be accompanied
by shrinkage, as formerly supposed, but may proceed according to the law of
equal volumes, as enunciated by Lindgren. Furthei-more, certain cases of ap-
parent inter-stratification of limestone and dolomite cited as evidence in favor
of some primary theory are rather pseudo-inter-stratifications, which have
resulted from selective dolomitization. Examples of limestones mottled with
dolomite were interpreted as representing an incipient stage in the process of
alteration. Organic factors have exerted a selective influence in some cases
of mottling, but in others the phenomenon is jturely inorganic.

Eead in full from manuscript.

1 Introduced by Stuart Weller.

ABSTRACTS OF TAPERS 63

RANGE AND RHYTHMIC ACTION OF SAND-BLAST EROSION PROM STUDIES IN

THE LIBYAN DESERT

BY WILLIAM H. IIOBBS

(Ahstract)

Although rock debris of a coarseness usually designated as sand is during
sand storms elevated by the wind to considerable though as yet undetermined
heights, there is evidence that the effective action of the sand-blast is limited
to a zone extending from the surface to a height of a few feet only. It is this
limited range which explains the characteristic mushroom rocks as well as the
luisymmetrical low ridges, with steep windward and flat leeward slopes, which
are found in many desert regions. Within the zone of effective action of the
blast the air is given a rliythmic motion which accounts not only for the ripple-
marks of dunes, but for a peculiar "ruffling" of the polished rock surface
strikingly similar tu the ruflied surface of a Inllow of water.

Presented by title in tlie absence of tlie author.

CORRASIVE EFFICIENCY OF NATURAL SAND-BLAST
BY CHARLES KEYES

(Abstract)

Tn the analysis of the effects of the erosive processes under tlie stimulus of
aridity sharp distinctions are to be drawn between those products whicli are
the result of weathering alone, those which are due to the transportative
capacities of the winds, and those which are strictly corrasive in character or
originate through natural sand-blast action.

The potency of natural sand-blast action is rendered particularly impressive
by recent engineering difliculties imposed by blowing sands that in various
parts of the world have had to be overcome. Since man has now entered
vigorously and successfully on the conquest of the desert, whicli occupies more
than one-fifth of the entire land surface of the globe, these difliculties iii the
arid regions multiply amazingly. The precautions taken to master them have
an important geologic bearing.

As is well known, the small sand-jet driven by compressed air is one of the
most efficient abrading tools at the service of man. In nature, also, there is a
near approach to the artificial sand-blast in the action of the rapidly propelled
sands of the desert. The extent of this action in arid lands attracts small
attention until it begins to interfere with human plans and works. Any geo-
logical effects that the power may have are largely obscured until, by the
elimination of the influences of the attendant powers, it is possible to iiuaiiti-
lativcly measure them.

Wiien attention is p:irticularly directed to the i>lienonienoii, I lie abiiuiing
fffect of wind-blown sands, especially in arid regions, is shown in ni:iiiy ways.
Glass windows of iiniiscs on the windward side of sand-wastes soon lose their
transi)aiTii('y liy tlu- conslaiit play of llic sands against them. The rapidity
witli wliicli tlie process takes itlace is indicated by the laMtcrii lenses of liglit-
hous'es being rendered useless by the action of wlnddrixcn siinds during a
single gale. When r.-irernlly I'xamincd. the e.xposed sides ot' tiu> irons of desert

64 PROCEEDINGS OF THE PHILADELPHIA MEETING

railways are often found to be roughened and etched by continuous impinging
sands. Short lengths of steel rail set for clearance posts in similar situations
are frequently distinctly girdled just above the ground and brightly polished.

In the arid regions of Arizona and New Mexico telegrapli wires and electric
ti-ansmi.ssion cables are kept bright by the blown dusts. As noted by J. Walther,
the telegraph wires of the Trans-Caspian railways have to be replaced about
evei-y decade because of the driven-sand action, which in that time reduces the
size of the wires to one-fourth of the original. Railway service on the Sahara
and other deserts meets with great obstacles due to the frequent terrific sand-
storms. One of these difficulties is sought to be overcome by the replacement
by spoked wheels of all solid wheels, because the latter under the incessant
sand-blast are found to wear so thin within a year's time as to be unfit for
further use.

The destructive effects of blown sands on buildings is noted by many ob-
servers. Wind corrasion of Heidelberg castle is often referred to. Injury to
building stones in cities by blown sand is especially discussed by T. Egleston,
who also calls attention to the fact of the gradual effacement of inscriptions
on city tombstones by dust blown from the street. The great obelisk at Heli-
opolis, near Cairo, displays blown dust or sand effects by the complete oblitera-
tion of the deeply cut hieroglyphics on the south and west faces — the sides
directed toward the prevailing winds off the Libyan Desert. Many Egyptian
monuments are, according to W. M. F. Petrie, badly injured by abrasion due
to wind-driven sands.

From a strictly geological angle the experimental aspects of sand-blast action
are especially considered in a number of recently published papers. My own
experiments were undertaken more for the purpose of establishing a rate of
abrasion than of merely establishing the fact. Bottles, panes of glass, and
rocks were exposed in situations where strong winds were driving the desert
sands over the surface of the ground. One wine bottle planted in the soil,
with top and bottom protected by cloth and an inch-wide band left in the
middle, was forgotten for nearly two years. Chancing to come across it at the
end of that period, it was found that the exposed band was entirely etched
through the glass for a distance of one-third of the circumference of the bottle.
I'anes of glass covered with paraffine figures presented ground surfaces, wher-
ever the wax was absent, that were distinctly visible after single severe sand-
storms. Hard, homogeneous and fine-grained rock faces were quickly polished,
while coarse-gi'ained granitic rocks were unevenly etched, the quartz grains
standing out in bold relief.

From the consideration of the local phenomena as mentioned, and the pro-
duction of faceted pebbles, sapped bounders, undermined cliffs, and the accen-
tuations of geologic structures, passage is made to some of the broader aspects
of the formation by the same means of the positive features of relief which
characterize desert regions — the production of cliff-lines, the origin of canyon
reentrants, the growth of desert escarpments, the genesis of plateau plains,
and the girdling of the desert ranges.

The rate of general sand-blast corrasion in arid lands is regarded as more
rapid than that of general stream corrasion in humid countries. In addition,
there are to be taken into account, in the consideration of the regional degra-
dation of desert tracts, both the effects of insulation and of deflation.

Presented by title in the absence of the author.

ABSTRACTS OF PAPERS 65

FALSE FAULT-SCARPS OF DESERT RANGES
BY CHARLES KEYES

{ Abstract)

Many of the conspicuous scarps bounding the mountain ridges of arid lands
])rove not to be features of faulting, as commonly supposed, nor to have any
relationships with dislocations of any kind. When the major fault-lines of
some of these mountain blocks are finally located, they are found usually to be
not at the foot of the orographic slopes, but miles out on the adjacent plains.
Although Dr. J. E. Spurr's recent statement that no one has ever seen such
fault-planes among the Great Basin ranges may be too sweeping in character,
it appears to be nevertheless a fact that the majority of the recorded cases re-
quire rigid verification before their accuracy may pass unchallenged.

In the case of certain desert ranges, as that of Fra Cristobel, an exception-
ally rugged block of tilted limestones in central New Mexico, the scarplike
face which rise.s out of the general plain of the Jornada del Muerto, is 500
feet high, but it is situated on the side of the mountain from which the strata
strongly dip. In other instances the mountain ridges present the so-called
fault-scarps on the side where the dips are into the mountain. Because of the
fact that the blocks are apparently upraised more on this side, and thus tilted,
the usual inference that there must be faulting to accovuit for the phenomenon
is not alwaj's correct. In still other cases, as the well known Sierra de los
Caballos, the mountain ridge is bounded on both sides by notable scarp-faces.
Finally, mountain blocks are not infrequently completely girdled.

The unbroken mountain block, which is oftentimes three to five times the
width of the present mountain base, is found to be cut back on a level with
the general plains surface in the same way that on an exposed shore of the
ocean a great .sea-cliff is formed.

This distinctly girdled belt appears to mark the zone of maximum lateral
deflation. Varying hardness of the rocks, their diverse attitudes, and their
relative arrangement or alternation seem to offer little resistance to the uni-
form extension of the surrounding plains. By means of the continual grind-
ing action of moving or wind-driven sands, constant flaking of soilless rock
surfaces, and deflation of comminuted rock-waste there appears to be, where
plain and mountain meet, a narrow zone, just above the sloping surface of the
former, where the destruction of the positive features of landscape goes on
much faster than anywhere else.

At the base of the mountains the remarkable truncation of the transverse
ribs, which is so characteristic of so many of the desert ranges, is believed
to be not evidence of tlie existence of noteworthy faulting, as is so generally
assumed to be the case, but a result of the sharp contest between wind and
water to master the local features of land sculpturing.

Presented bv title in the absence of tlic author,

66 PROCEEDINGS OF THE PHILADELPHIA MEETING

STRATIGRAPHIC DISTURBANCE THROUGH THE OHIO VALLEY RUNNING FROM
THE APPALACHIAN PLATEAU IN PENNSYLVANIA TO THE OZARK MOUN-
TAINS IN MISSOURI

BY JAMES n. GARDNER

(Abstract)

A line of disturbance in ttie eartli's strata, wliich at some points consists of
an anticline and at others of a fault zone, runs from rennsylvania through
the Ohio Valley to Missouri. Beginning as the Chestnut Ridge anticline in
the Appalachian Plateau of Pennsylvania, it passes through West Virginia as
the Chestnut Ridge and Warfield anticline, through Kentucky as the Cannel
City-Campton-Irvine anticline, Kentucky River and Dividing Ridge fault, and
Rough Creek uplift; thence across southern Illinois as the Shawneetown
fault and Bald Hill uplift, crossing the Mississippi River to the Ozark arch.
It lies south of the Ohio River and I'oughly parallels it, cutting across the
Cincinnati geanticline in Kentucky. At three points along near its course
there are known intrusions of peridotite dikes, namely, in Fayette County,
Pennsylvania ; Elliott County, Kentucky, and the west Kentucky-Illinois fluor-
spar district. Tliis structural zone is now known throughout a distance of
560 miles.

Presented by title in the absence of the author,

PRELIMINARY PAPER ON RECENT CRUSTAL MOVEMENTS IN THE LAKE ERIE

REGION

BY CHARLES E. DECKER *

{Abstract)

In northeastern Ohio and in the northwestern parts of Pennsylvania and
New York there are numerous folds and faults exposed in the valleys of
streams tributary to Lake Erie and in the lake cliffs. The purpose of the
present study was to determine the extent, age, distribution, and significance
of these movements.

Two points had already been brought out by this study. First, many of
these movements have taken place in recent geological time. Second, while
the area affected has not been completely outlined, the rocks of this area have
suffered deformation in a manner not duplicated in the rocks of adjacent
glaciated areas.

Evidence of recency was produced to show that many of the crustal move-
ments are not only postglacial, but that they are later than the terraces and
floodplains of the streams.

Eead in full from manuscript.

Discussion

Dr. I. C. White: Tlic i-cuimi discussed in tliis p.-ijuT all lies within the gla-
ciated belt of soft, tliiii-bcdiled I>evonian sliales. I had occasion to examine

1 Introduced by Richard R. Uice.

ABSTRACTS OF PAPERS 67

the same region during the progress of the Second Geological Survey of Penn-
sylvania, covering the region of Cravvrforcl and Erie counties, the latter of
which borders Lake Erie. It was my conclusion that many of these minor
folds, especially tliose with steep dips, were formed by the glacial ice, the
iKuilders imbedded In its base creating much friction on the yielding shales.
The absence of erosion of these folds would be no evidence against this theory
of their formation, since there has been no erosion, except along the streams
and gullies, since the Ice Age. Of course, along the streams the removal of
overlying materials and the consequent release of tension would be a true
cause for the very small flexures observed in such locations.

Dr. Richard R. Hice : Some at least of the faults involve a greater thick-
ness of strata than suggested. At least one fault on Elk Creek extends down-
ward a considerable depth, as is evidenced by gas flow. The folds near Mead-
ville are due to release of load by the eroding streams. The rocks being under
compress, they have "buckled up" when the stream eroded the overlying rocks.

Mr. F. B. Taylor: Tliere are a number of folds of this type in the slides
along the north side of Lake Ontario between Hamilton and Toronto. Sev-
eral of them extend 200 or .'UK) yards. These particular folds lie in the surf-
wasted zone of the Iroquois beach and appear certainly to be of more recent
date than that beach.

Mr. Decker replied that the area under consideration (northeastern Ohio
and northwestern Pennsylvania and New York) has suffered recent deforma-
tive movements in a manner not duplicated in adjacent glaciated areas, though
they contain rocks of similar composition. This suggests that glaciation is
not responsible for the deformation and much of it is certainly postglacial.

Further remarks were made by Messrs. H. F. Eeid and H. M. Ami.

QUATERNARY DEFORMATION IN SOUTHERN ILLINOIS AND SOUTHEASTERN

MISSOURI

BY EUGENE WESLEY SHAW

(Abstract)

That the Ozarks, at least the northeastern part, have suffered uplift since
middle or late Tertiary time, and that this deformation was not a single brief
movement but has proceeded, probably with interruptions, during part or all
of several epochs, are indicated by the following facts :

1. Two terraces, formed by the dissection of valley flllings, rise toward the
Ozarks, though in most of the valleys of southern Illinois this is downstream,
and the form of the surface is such as to preclude the possibility that the
streams have been reversed.

2. Well records show that the old valley bottoms underneath the fillings are
also tilted up a little toward the Ozarks.

3. The two terraces appear to diverge slightly to the southwest, indicating
s(.iii(> doformation between the times of valley filling that is, between the
middle and late parts of the Pleistocene epoch.

4. The valleys and terraces become narrower (<• the soutliwest towanl the

68 PROCEEDINGS OF THE PHILADELPHIA MEETING

hill country, <'iii«l in this narrowing do not show a close relation to rock hard-
ness.

5. About the margin of the Ozarks a peneplain, probably of Tertiary age,
has apparently been tilted rather sharply, so that it now slopes strongly toward
the lowland to the northeast, and this slope is to a considerable degree inde-
pendent of rock structui-e and drainage lines.

6. The surface features, the structure, and the buried peneplains of the
upper end of the Mississippi embay ment seem to show uplift since the Ter-
tiary strata were laid down.

7. The position of the Mississippi River shows lack of adjustment, for it
flows on the side of a trough, both structural and physiographic. The natural
place for the river between St. Louis and Cairo is in the low, soft rock country
50 miles or more east of its present position, and the evidence is now practi-
cally conclusive that it was not forced out of such a course by a glacier, and
also that it is not a superposed stream.

8. The drainage on the east side of the Mississippi is undergoing readjust-
ment, the principal process being the development of many new small tribu-
taries which are driving divides eastward.

9. Certain facts suggest that the valley of the Mississippi has in large part
been carved in Pleistocene time, and apparently its youth and the topographic
unconformity between it and the bordering surface forms, though due in pari
to enlargement of basin and perhaps glacial floods, can not be fully accounted
for except through deformation.

10. The foi'm of the valleys of the Ozarks is believed by the writer to be
such as to indicate that for the most part they ha^e been carved since late
Tertiary time, and the lower parts of them in particular show evidence of
comparatively recent uplift.

Some facts suggest that the deformation consisted in part of downwarp of
the southern Illinois and western Kentucky lowlands; but however that may
be. the downstream rise of terraces and buried valley bottoms seems susceptible
of no interpretation other than relative uplift, and this, together with the fact
that the other lines of evidence are accordant, are believed to put on a firm
basis the conclusion that this region has suffered deformation in late Tertiary
and Quaternary time.

Presented by title in the absence of the author.

OLD SHORELINES OF MACKINAC ISLAND AND THEIR RELATIONS TO THE

LAKE HISTORY

BY FRANK B. TAYLOB

{Abstract)

The old shorelines of Mackinac Island have been studied recently in much
more detail than formerly and have been placed on a large map with scale
of 200 feet to one inch and contour interval of 10 feet. The work is being
done by tlie Michigan Geological Survey and will be the subject of a report in
the near future.

When mapped in this more complete way the beaches bring out with much

ABSTRACTS OF PAPERS 69

greater clearness than before the larger facts of the lake history as recorded
in the northern lake basins.

The small ancient island which forms the hump on the back of the "great
turtle" is surrounded on three sides by a compact and strongly developed
series of gravel ridges — the upper group of the Algonquin beaches. On the east
side the waves of the same time cut heavily into the ancient island, leaving a
cliff of limestone over 100 feet high. The rock fragments torn from this side
supplied the main bulk of the material for the beach ridges on the other sides.
The lower limit of this group is just as sharply defined as the upper limit.
The vertical interval covered by the group is about 35 feet, measured from
the highest to the lowest beach crest, or nearly 50 feet to the base of the lowest.
This highest beach is 809 feet above sealevel, or about 229 feet above Lake
Huron. There is a little gravel about 3 feet higher, but it has not the form
of a wave-made beach.

Below the base of the upper group a space covering a vertical interval of
about 110 feet has only a few beaches, nearly all weak and fragmentary.
These are the Battlefield and Fort Brady beaches of the late stages of Lake
Algonquin. The upper part of this interval is heavily wave-washed and is
mainly bare rock, or carries only very thin soil. This wave work was accom-
plished during the making of the upper group of Algonquin beaches.

Below the Fort Brady group of the Algonquin comes the Nipissing and lower
beaches. These are strongly developed, and where beach building was favored
they cover the entire slope from the Nipissing down. At Mackinac Island the
vertical interval which they cover is about 50 feet; thus at Mackinac the
record of the lake history is expressed in two strong groups of closely set
beaches, with a relatively wide, nearly barren interval between — two zones of
prolonged wave action separated by an interval showing very little wave
action.

The two strong beach belts correspond to times of relatively permanent or
slowly changing levels of the lake waters — to the second and third or two
main stages of Lake Algonquin and to the transitional or two-outlet stage of
the Nipissing Great Lakes, with a considerable part of the post-Nipissing or
present stage. The barren zone between these belts corresponds to the time
of the relatively rapid uplifting of the land in the closing stages of Lake
Algonquin. These stages of relative stability and of rapid uplifting were
worked out more fully in earlier studies covering much of the lake region, and
the details on Mackinac Island agree with those results. The island is small,
hut it is relatively high, and stands in the midst of the northern waters like
a monument bearing the record oC the lake stages and uplifts that affected
that region.

It has been held by some that strong beach ridges, like those of the Upper
Algonquin group, mark as many pauses in the uplifting movement of the land;
but this idea is apparently disproved by both of the heavy beach series on
Mackinac Island. On the south sirle of the ancient island the Upper Algonquin
group is represented by eleven or twelve beach ridges — by six strong ones and
five or six weak ones — whereas on the west side about forty well defined ridges
cover the same vertical interval. The forty ridges are spread over a wider
liorizoiifal area, but their averag(> stroncth of development is loss, as would
be expected in a less exi>osed jmsition. wliere wave action was weaker.

VI— Buu.. Geol. See. A.M., Vor. L'C. 1014

70 PROCEEDINGS OF THE PHILADELPHIA MEETING

The same general comparison holds for the Nipissing-post-Niplssing series
of beaches at the south and north ends of the island, the more ninnerons
series at the north having been built by much less powerful waves than those
at the south. It does not seem possible in this case to account for the indi-
vidual ridges by pauses in uplift. Rather do they seem determined by the
amplitude of the waves, the breadth and character of the subaqueous slope,
the supply of beach-making material, and by other factors. The beaches and
I>arren intervals of the Battlefield and Fort Brady groups seem more clearly
related to variations in the rate of uplift. It seems certain, for example, that
the strongest ridge of the Battlefield group marks a well defined pause, and
it is even more certain that the strongly marked barren intervals do not
record pauses.

Presenter] in abstract from notes.

SOME PECULIARITIES OF GLACIAL EROSION NEAR THE MARGIN OF THE
CONTINENTAL GLACIER IN CENTRAL ILLINOIS

BY JOHN L. RICH

(Ahstract)

Few specific observations ai'e on record of the amount of erosion which the
continental glacier accomplished on the plains of central United States, in the
zone of predominant deposition near its margin, though the statement is often
made that the amount was slight.^

The opening of an extensive limestone quarry at Fairmont, Vei'milion
County, Illinois, has brought to light definite evidence on this point and on
the nature of the ice-movement here, 30 miles within the extreme limits of the
early Wisconsin glacier (figure 1).

The quarry is in a bed of limestone about 20 feet thick, which appears to
be a local lens in the midst of horizontal Pennsylvanian shales. Its site stands
about 15 to 20 feet above the level of the surrounding plains; hence must have
been, on the whole, more exposed to glacial erosion than were its surroimdings.
The limestone at the quarry is overlain by 8 to 15 feet of drift. Extensive
stripping operations have revealed the surface of the rock round an elliptical
area roughly i/£. mile by % mile in extent, giving most excellent opportunities
for a study of glacial action.

The effects of underground water on the limestone are conspicuous. .Toints
have been enlarged by solution, and locally, at their intersections, caverns 3
or 4 feet in diameter have been developed.

1 The following papers bear more or less directly on the problems under discussion :

W. H. Norton : Glaciated rock surfaces near Linn and near Quarry, Iowa. Proc.
Iowa Acad. Sci„ vol. 18, 1911, pp. 79-83.

Frank Carney : Glacial erosion on Kellys Island. Ohio. Bull. Geol. Soc. Am., vol. 20,
1910, pp. 640-645.

William H. Sherzer : Ice worlj in southeastern Michigan. .Tour. Geol., vol. 10, 1902,
pp. 194-216.

H. L. Fairchild : Ice-ero.sion theory a fallacy. Bull. Geol. Soc. Am., vol. 10, 190.5,
pp. 1.3-74.

Frank Levereft: The Illinois glacial lobe. Mon. U. S. Geol. Survey, vol. .S8, 1S99,
pp. 8.5-87.

T. C. Chamberlin : Seventh Ann. Rept. U. S. Geol. Survey, especially page 187.

ABSTRACTS OF PAPERS

X= Location of-
Fairmont Quarry

FiGURK 1. — fiketrh Mnit af llliliDix
Showing locatluD of Fuiiiuonl iinany \\i(li icspcct lo limit of early WisconBin glacier

72 PROCEEDINGS OF THE PHILADELPHIA MEETING

The question arose whether these solution effects had been produced before
or since the invasion of the region by the glacier. The perfectly fresh appear-
ance of the striae, as compared with the weathered, etched, and pitted surfaces
of the joint cracks and caverns, pointed toward the preglaciaP origin of the
latter. So also did the fact that in several places caverns were cleanly cut
across by the glacial surface (plate 7. figure 1). In one instance a work-
man, noticing that the rock sounded hollow, drove his crowbar throiigh about
one inch of striated limestone into a good-sized cavern. Decisive evidence on
the point was secured when it was found, in one of the higher parts of the
qiiarry, that glacial strife descended to the depth of about a foot into one of
the enlarged joints which happened to lie in a direction parallel to that of the
ice-movement (plate 7, figure 2).

The pre-Wisconsin age of the solution phenomena having been established,
it becomes possible to use these in estimating the character and amount of
ice erosion which the limestone has suffered. When this line of investigation
is followed it leads at once to the conclusion that erosion has been very un-
equal in different parts of the quarry. The surface of the limestone varies
slightl.y in elevation, possibly as much as 10 feet within the area exposed.
On the higher parts erosion has been intense enough to plane away all irregu-
larities and to leave an almost perfectly smooth surface. It has not, however,
been sufficient to obliterate the caverns or the solution channels along the
joints. A conservative estimate would place the thickness of rock scoured
away at not more than 2 to 4 feet. Over those parts of the quarry lying at
intermediate levels a large part of the surface has been planed smooth, but
the bottoms of the solution hollows have not been touched. Such a condition
indicates very moderate erosion — not over 1 or 2 feet at most. In the lowest
parts of the quarry the ice scarcely reached the rock. Ozily the highest pro-
jections were planed off. The surface, as revealed by stripping in one of the
lowest parts of the quarry, resembles in every way that of weathered lime-
stone in an unglaciated region (plate 7. figure 3).

In detail, as well as in broader features, the distribution of the eroded sur-
faces reveals the inability of the ice to descend into hollows, even where
broad and shallow. Depressions 20 or more feet in diameter and less than
1 foot deep have escaped erosion, while the surroimding rocks have been planed
off. Even the far sides of such depres.sions, where the erosive action should
have been greatest, are commonly unstriated. In passing over smaller de-
pressions, such as caverns or solution-enlarged joints, the ice seems not to
have sagged downward in the least.

Such conditions show clearly that the ice behaved like a rigid plane, which
actively eroded the higher projecting points, but was totally unable to descend
into the depressions, even though they were broad and shallow. In the higher,
more exposed parts of the quarry it bulged down slightly into solution channels,
whose direction happened to be parallel to that of its movement ; but it seems
never to have descended into the transverse joints.

The ice doubtless rode over all these depressions on its own debris, but the
significant feature is that it failed to clear this away and to scour down every-

- The word preglacial is used here in the sense of certainly pre- Wisconsin and possibly
even pre-lllinoisan or pro-Kansan. No data are at hand to show how innch of the solu-
tion should be attributed to interglacial and how much to strictly preglacial weathering.

BULL. GEOL. SOC. AM.

VOL. 26, 1914, PL. 7

Figure 1. — Cavern cut Across by GLACi.iL Erosion

Greatest wiJth about IS inches. Note sharp angle between glaciated and unglaciated
surfaces even where cavern extends parallel to the stria;

oj9'~-

ProDRE 2. — An Enlarged joint Cavern
Upper foot smoothed and striated by ice : proof of pre-Glacial age of solution effects

I'h.l Ul.

\\ i.A ui ii.i.u Si K I w I . •! 1 ,1 I I - I . . ^ I I; I \ i.u.i;ii r. \ i.ii \i;i: n S iui I'l'l ng

Note the enlarged Joints; also ihr snluiion piis nii ihr top surfaci' nl' ihc liriu>stone. The
arrow iinints Id llic cmly spol within llir I'k'IiI hI virw wliicli was Imu-hcd l)y the ice

PECULIARITIES OF GLACIAL ERO.SION IN CENTRAL ILLINOIS

ABSTRACTS OF PAPERS 73

where to live rock, in spite of irregularities iu the surface, as it did in so
many well known instances where it was thicker and its motion more vigorous.

The thinness of the ice in this submargiual area and its consequent insig-
nificant weight, combined with a dominant translative element of motion, are
thought to he responsible for these features. The effects are such as should
be expected from a rigid mass of ice pushed bodily along from behind.

Since the quarry lies higher than its surroundings, erosion there doubtless
represents a maximum for the region. If so, the lower, less exposed parts
of the plain nmst have suffered exceedingly little, if any, erosion.

Read in full from manuscript.

Discussion

Mr. F. B. Taylor : The phenomena described by Mr. Rich is characteristic
of a zone near tlie edge of the ice. At some other localities — Kellys Island,
in Lake Erie; the Sibley quarry near Trenton, Miebigan ; on the Niagara es-
carpment near Fekin, New York, and on the Saugeen peninsula, iu Ontario —
the ice adapted itself to an irregular surface, either following narrow sinuous
troughs or dipping down into shallow basins. These effects are apparently
associated with relatively deep ice which was somewhat plastic and adapted
itself to the hollows. Mr. Rich's pictures show an interesting exception, prob-
ably related to the thin marginal part of the ice.

Dr. C. A. Davis : In the vicinity of Marquette, Michigan, on the top of a
rock hill within the city limits and 200 feet or more above Lake Superior, and
in direct line of ice-movement — that is, facing the northeast — in 1906 there
was seen an area of the schists of the region and an amphibolite dike on which
the pre-Wisconsiu weathering had not been removed by the erosion of the last
ice-sheet, as shown by the surface of the schist, and especially by a small area
on the surface of the dike, in which included quartz pebbles had weathered
out for an inch or more in a shallow depression. The margins of the depres-
sion were beautifully glaciated, and the tops of the inclusions were truncated
and striated ; Imt tbe ice had not eroded to the bottom of the slight depression.
Theoretically (his should be a locality where ice erosion should have been
heavy.

Mr. Rich asked if the term "solution pipe" was a good one to apply to
solution-enlarged joints.

Further remarks wei'c made by H. P. Reid and H. M. Ami.

NEW EVIDENCE OF THE EXISTENCE OF FIXED ANTICYCLONES ABOVE

CONTINENTAL GLACIERS

BY WILLIAM HERBERT HOBBS

(Abstract)

In 1010, wlioi) the writer first asscinblod the evidence and prunuilgated the
tbeory of nouiisbuieiil of loiitineiital glaciL-rs Iroiii (lie cirri tbroiigli (be agency
of glacial anticyclones, the available evidence consisted of the following :

74 PROCEEDINGS OF THE PHILADELPHIA MEETING

1. The generally centrifugal flow of surface air currents above the domes
of inland ice.

2. The areas of relative calm over the central bosses of these ice domes.

3. The gradual working up of the glacial blizzards and their abrupt termi-
uations in a sudden elevation of air temperatures (foehn effect).

-1. The saturation of the air above the central areas of calm and the pre-
cipitation of snow or ice within the zone near the glacier surface.

.">. The general paucity of other than wind-driven snow falling over the
outer slopes of the ice domes.

G. The centripetal flow of upper air currents shown by the drift of clouds
and of volcanic vapors.

7. The predominance of the cirri above inland ice, except at its margins.

S. The centrifugal drift of the snow from the central areas of continental
glaciers and its accumulation in grabular form about their margins, and par-
ticularly at the base of outlet glaciers.

In the four years which have elapsed since this theory was promulgated the
volume of evidence along most of these lines has been greatly augmented
through the publication of scientific reports on expeditions carried out before
the theory was published, but far more by the preliminary reports on new
explorations within the two principal areas. These expeditions are notably
the crossings of Greenland by De Quervain in 1912 and by Koch and Wegener
in 1913, and the Antarctic expeditions of Captain Amundsen, Captain Scott,
Lieutenant Filchner, and Sir Douglas Mawson. To the amplification of evi-
dence along the above designated lines there has now been added the revelation
of strong inversions of the atmosphere about the glacier margins and an up-
ward extension of the outward flowing air currents, made known by ascents
of kites and of pilot and registering balhxjns. The purpose of this paper was
to draw attention to this new evidence.

Presented by title in the absence of the author.

ORIGIN OF MONKS MOUND
BY A. B, CROOK

(Abstract)

Monks Mound, the largest of the Cahokia group of mounds, situated 6 miles
east of Saint Louis, has for many years been described by archeologists as the
"largest artificial mound" in existence.

Twenty-five borings were made in the north and most abrupt side. 1. They
showed different strata at different elevations. 2. These strata agree with
similar elevations in the other mounds and with soil from the bluff 2 miles
away. 3. Fossil hackberry seeds (Celtis occidcntalis) and such gasteropods
as Pyramidula, Succinen, Heliciiia, and Pliysa are found in beds. 4. A study
of the physiography of the mounds makes clear that they occur along the
divide between streams, and that their arrangement and individual forms are
characteristic of the remnants of stream cutting.

Chemical and mineralogical .study of the soil, as well as paleontological and
physiographical investigations, indicate that the mounds are the remnants of

ABSTRACTS OP PAPERS

/.)

the glacial and alluvial deposits which at one time filled the valley of the
Mississippi River in this region.

It may be well to inijuire if all so-called mounds in the Mississippi Valley
are not natural topographic forms.

Presented in abstract from notes.

Discussed by Messrs. John L. Eieh and A. E. Crook.

CAN V-SHAPED VALLEYS BE PRODUCED BY REMOVAL OF TALUS?

BY ALFRED C. LANE

(Abstract)

The top of a talus slope accumulating at the foot of a vertical cliff of height
(h) describes a convex curve, which, if n (the ratio of increase of volume
occupied by a given weight of rock when broken into talus, usually 1.5 to 2)
be 1, if s is the slope of repose, usually .6 to .7, and if y/ be measured fi-oui
the foot of the cliff, x from the initial face, is a parabola '2lis.c = //=. If n is
not 1, the curve is similar, but has the more complex expression,

(1 — n) sxh— (y/h) J^ (n/ (n — 1)) nat. log (1— (v/ — 1) ij/nh)

A cross-section of a talus pile is like a jib or lateen sail, pteroid. Scenic
curves may be found which seem to have this origin, but they are just the re-
verse of the U-shaped curves of many glacial valleys, which can not have been
formed by the mere cleaning out of a widened I-shaped canyon (see figure li.

FiOCKi: 1.- Talus iiroilutcil bu tha Retreat uf the lc> lical (.'tiff AU, alluwintj fur hilrral

Weatheriitij only

The slope of the angle of repose (35°) Is taken as .7. CG Is a parabola and r(il<' is
the shai>o of cross-section, If the rock is supposed to occupy the same Itiilk in talus as In
cliff — that is, ('(;!'' = ACC in = 1). H<JK is the shape of the section. If the rock in talus
occupies twice the l)uik Ihal it does in the clilf, B(1E -- 215GA(» = li).

In real views sliowing somewhat this type of prollle (see American I'-orestry, June,
1914, p. ;J9.') ; Twentieth Ann. Kept., U. S. Geological Survey, part v. pi. ixKt the angle
at BC Is rounded, as the weathering Is never iiureiy lateral.

Presented by title in the absence of the aiitlior.

76 PROCEEDINGS OF THE PHILADELPHIA MEETING

PHYSIOGRAPHIC STUDIES IN THE DRIFTLESS AREA
BY ARTHUB C. TROWBRIDGE

(Abstract)

Physiographic work done aud iu progress in northwestern Illinois, north-
eastern Iowa, southeastern Minnesota, and portions of Wisconsin, under the
auspices of the University of Iowa, the University of Chicago, aud the Geolog-
ical Surveys of Iowa and Illinois, is yielding new data on the history of the
driftless area.

The data so far gathered belong under three heads: (1) The Upland Plains,
(2) The Glacial Drifts, and (3) The History of Drainage.

There are two upland plains, both of which are old peneplains. The highest
and oldest one slopes from 1,500 feet above tide at Baraboo, Wisconsin, to
1,200 feet at Dubuque, Iowa, and cuts across from Huronian quartzite at
Baraboo to Niagarau dolomite at Dubuque. Evidence points to the late Ter-
tiary age of this plain. The younger peneplain has been traced from Jo Daviess
County, Illinois, where it lies on Maquoketa shale and Galena dolomite at an
altitude of 900 feet, to New Albin, Iowa, at which poiut it has an altitude of
1,100 feet and lies on the Prairie du Chien formation. Pre-Kansau glacial
drift found on this plain iu Iowa places its age as early Pleistocene.

The glacial drifts of the region include (1) pre-Kansan drift on the Pleisto-
cene peneplain in Iowa, (2) Kansau Valley trains in tributaries to the Mis-
sissippi from the west, (3) Illinoisan drift on the east border of the driftless
area in Illinois, (4) Wisconsin till in Wisconsin and fluvo-glacial material of
the same age in the main valleys throughout the area, and (5) weathered till
aud fluvio-glacial material of unknown age and derivation at Bridgeport, Wis-
consin.

A study of drainage lines has led to the discovery of new data on the
Pleistocene history of the area. For instance, the Upper Iowa River iu Iowa
cut a valley 600 feet deep during the Aftonian interglacial epoch. Couler
Valley, at Dubuque, has ahso an interesting history, which throws light on the
duration of interglacial epochs. There is no evidence of a pre-Pleistocene Mis-
sissippi River. The Mississippi gorge was cut from a level of 900 feet at
Dubuque to 276 feet at the same place, between Jerseyau aud Wisconsin times,
and the stream is now at grade ou Wisconsin material 324 feet above its pre-
Wisconsin level.

This work will be carried further during the coming and following years.

Presented by title in the absence of the author.

HEMWONES AT THE MOUTHS OF HANOINO VALLEYS
BY CHARLES E. DECKER *

(Ahstract)

On the south side of Lake Erie numerous small streams tributary to the
larger creeks enter the main valleys through hanging valleys. Similarly, some
of the small streams east of Erie, Pennsylvania, enter the lake through hang-

ABSTRACTS OF PAPERS 77

ing valleys. At the mouths of the hanging valleys projections occur into the
main valleys or into the lake. These projections are here given the name of
"hemicones." The purpose of this paper was to illu.strate these hemicones
and to briefly consider their origin.

Read in full from manuscript.

BLOCK DIAGRAMS OF STATE PHYSIOGRAPHY
BY A. K. LOBECK '

(Al)stract)

The broader physiographic features of a state, or a large i)ortion of a state,
may best be portrayed by means of a block diagram which shows the relation
of surface form to underground structure. The possibilities of this use of the
block diagram method were illustrated by several .specimen di-awings.

Eead by title, drawings being on view in exhibition room,

KILAVEA, A DROP-FAULT CRATER
BY GEORGE CARROLL CURTIS ^

{Abstract)

On withdrawal of molten lava in the active pit of Halemaumau, support to
the adjacent walls of frozen lava is lost and blocks of it subside, taking a
form roughly concentric with that of the liquid lake. Such down-faulted
masses are common within the eruption pit, its rim being stepped with series
of corresponding lesser faults and cracks. The great caldera (Dutton) rim,
of some 9 miles in circumference, 3 in diameter, and reaching nearly 300 feet
in height, surrounds a floor or sink which appears to represent the "black
ledges" or flow levels in the present pit of eruption, and large down-faulted
blocks lie like giant steps along its extensive scarp.

Outside the main rim, interrupting the gentle slopes of the Kilauea cone,
are other escarpments which appear of similar origin, one at half a mile and
another at about a mile distant being the highest. The broad saddle between
Kilauea and Kilauea Iki is a comparatively large dropped fault block, and
a similar series of blocks and fissures occur in the several dormant surround-
ing crater pits. Kilauea is perhaps the best example of the drop-fault volcanic
crater.

Presented by title in the absence of the author.

1 Introduced by Richard I£. Hice.
^ Introduced by E. O. Hovey.

78 PROCEEDINGS OF THE PHILADELPHIA MEETING

AOE AS THE DETERMINANT OF CHARACTER IN VOLCANOES
BY GEORGE CARROLL CURTIS ^

{Abstract)

It hns been held liy some vnleandloglsts that a frngmental character of
ejecta marks the closing stage of \olcauic eruption. While this seems to apply
in some localities, notably the Hawaiian group, the opposite was noted by the
writer in other Pacific archipelagoes — in tlie Philippines, in Japan, and espe-
cially in Java — where a large number of fragmental volcanic cones in all
stages are found, the most energetic, Smeroe and Bromo, being in constant
activity. Pele and Taal, whose eruptions and destruction of life had remark-
able similarity, though composite cones, have been fragmental in their latest
outbreaks, and many other like cases may be noted.

It appears that character of ejection is not always a criterion for determin-
ing the stage in the life history of a volcano.

Presented by title in the absence of the author.

COMPREHENSIVE CORAL ISLAND THEORY
BY GEORGE CABBOLL CURTIS ^

(Abstract)

Several one-way theories have been advanced for the true solution of coral
atoll formation, Darwin's subsidence theory being the most widely accepted.
A. Agassiz's views, based on the most extensive field observations yet made
on coral reefs, seem to be the most inclusive. No single theory will fully
account for all existing islands, though subsidence, platform building on reef
talus, marine erosion, continental glaciation, and other factors, ably presented
by eminent authorities, have undoubtedly entered into the construction of ex-
isting reefs. A year's study Ln South Pacific coral seas, with four years of
coral island work, including the construction of the reliefs of Borabora and
I'unafute islands, has led to the tenet that similar results in coral formations
may be brought about by quite different combinations of processes, and that
the most plausible coral island theory for the time being is the multi-cause
and vari-cause one.

Presented by title in the absence of the author.

EVIDENCE OF CONTINENTAL GLACIATION ON MOUNT KATAHDIN
BY GEORGE CARROLL CURTIS *

{Abstract)

Jackson, Bailey, Ilaiiilin. Tarr, and other geologists have reported on the
glaciation of the Mount Katahdin region. Professor Tarr's work being last and

1 Introduced by E. O. Hovey.

ABSTRACTS OF PAPERS 79

naturally most comprehensive. He held that the Labrador ice-sheet passed
completely over the mountain, basing his view^ on a few small erratics found
near the summit. On a short visit this fall, the vrriter noted the angular
character of the rock surfaces in the summit region and also the general
absence of glacial drift, striation, and other signs of glaciation, though at 400
feet below the top such glacial effects were plentiful.

It seems from the data that, though the continental ice may have passed
over this highest point in Maine (there is abundance of local Alpine glaciation
in the heading valleys), evidence to establish complete overriding by the ice-
slieet seems to be wanting. Katahdin has been at least an eminent uunatak.

Presented hy title in lliu absence of the author.

NATURALISTIC LAND MODEL, THE "LAST WORD IN GEOLOGY"
BY GEORGE CARROLL CURTIS *

(Abstract)

strange as it may appear on first consideration, one of the most inclusive
subjects in earth science, calling for much detailed study and critical obser-
^■ation, broad, useful, and illuminating, is generally known only in its smallest
and by far the least interesting aspect — the mechanical rather than rational
side.

After the preliminary work of topographic mapping has been done, the most
complete plotting finished, the culture, forest, vegetation, or other natural
features added, the geology surveyed and placed upon the plan, the step which
follows, in order to present the most complete representation of the earth's
surface, is to gather the remaining data and render it all in the form of a
naturalistic land model. In amount of facts, completeness, accuracy ; in the
matter of permanence and of characteristic natural expression, this medium-
combining data of all other surveys with that especially i-equired l)y its own
dcni.'inds seems to be entitled to the phrase "The last word in the earth sci-
ences."

If it has been difficult for some geologists to see how there can be depth to
such a subject, this may be due to old associations or to a habit of mind: Iiut
it is no fault of the nature of the naturalistic model. When one begins to
realize that the reproduction of the face of the earth as it stands in the field
is a d(>flnite problem in natural science and not, as it ma.v have been hastily
conceived, merely the mechanical raising of maps into relief, the whole aspect
of the subject changes; it is seen to be rational, vital, and of tnilimited possi-
bilities. In tliis niediuni. so peculiarly neglectetl by ucnlogists. tiie earth sci-
ences have one of their greatest opportunities and a future which there is
good reason to lielieve may surpass in general interest anything yet achieved
in geology.

The first naturalistic relief of a land-form type made in this country has
been brought about; it came through the efforts of biologists.' It was Alex-

' Introduced by K. O. iTovcy.

= Tho roral is];in(l iikhIcI i<( r.draliorji, Taliili, inslalli'd in ilir llai'\arii Miisciitii of
("omparativf Zoology in 10(17.

80 PROCEEDINGS OF THE PHILADELPHIA MEETING

ander Agassiz, primarily a zoologist, who, after becoming tlie best informed
authority on coral reefs, piclved a second nugget from the field of geology in
first introducing into an American museum a naturalistic model of a topo-
graphic type. Some geologists apparently do not realize the light in which
their subject has Iteen placed through lack of recognition of the need of expert
direction in this sub.ject, so fundamentally belonging to earth science; nor the
credit lost by first rt^cognition liy other scientific bodies.^ The crude reliefs
that have characterized the works of American geologists, especially in gov-
ernment service, lias presented geology in an unfavorable light and spread an
impression of lack of accuracy and perception which does us injustice. What
is by rights a most expressive and broadly interesting work has been shown
in its smallest phase too arbitrary to attract the interest of any save a few
specialists; and so geology has lost the tmi(iue advantage that might come
from utilizing its best medium of exposition. One result is the maintenance
of a low standard of land relief work throughout the many and varied channels
where its uses are continually sought throughout the country. Government
scientific bureaus are naturally looked to for standards, and failing to recog-
nize expert work in a subject in which they are presumed to be authorized is
bound to uphold poor standards, placing earth science in an unfavorable light.
Is the interpretation of the earth's surface a matter so simple as to call for
no such special training as is foiuid necessary in the other arts? Can geolo-
gists think so poorly of their science as to hold that the training of mechanics
is sufficient to interpret the intricate forms of the landscape, and is so mean
a consideration of earth structure in accord with the spirit of modern nature
study?

After architects, biologists, landscape gardeners, educators, and others into
whose fields of labor this most inclusive branch of earth science has pene-
trated, have derived signal advantage fnim its promotion, it is interesting to
note that now, for the first time. American geologists are entering this field
so intimately a part of their work and the public need in earth study. The
curator of the Harvard Geological Museum has taken this initial step among
his fellow-geologists to bring a natviral history specimen of a type of land
form into an American geological museum. Three months were spent in a
special survey for relief data of the crater of Kilauea, islands of Hawaii, and
after nearly two years' continuous work under direction of a professional land
modeler, the volcano is now approaching completion in the work of naturalistic
relief.

Few realize the field study, planning, vast amount of laboratory work, and
the expert direction (regardless of certain necessary technique gained only
by long and costly experience) that expressive naturalistic relief involves;
and yet when we consider for what it truly stands and can represent in its
very completeness — not maps, but the field as it is and appears — we see that
adequate results could not come otherwise. How many topographic reliefs in
our museums today are based on the special surveys required for naturalistic
models? And how man.v have been carried out for geology by expert land
modelers? What encoui-agement has previously been given such workers by
oui- earth scientists? How uuieh has our government Geological Survey, to

^ "Gpographic scnlptiiip" was first honored iu this country by the American Social
Science Association iu 1014.

ABSTRACTS OF PAPERS 81

which tlie public looks for standards, done for the promotion of land relief
work? How much notable work dignifies and illuminates American geology
in our National Museum? Other institutions have fortunately proven l)y con-
crete example that nothing else is so capable of arousing as large an interest
in earth science as the naturalistic relief.

As land reproduction in relief is one of the most inclusive sulijects in the
earth sciences, it is. old opinion notwithstanding, one of the larger sul)jects
in geology and geography, and it is pertinent to note that some geologists now
iire beginning to see more clearly their great opportunity long overlooked.
This insight should lead to a demand for more dignified work and help to
change conditions (indirectly responsible for the large amount of unsatisfac-
tory work in our museums, institutions, and expositions) whicli have made
it practically impossible to do good work in this subject in our government
bureaus. It may help to pave the way for geology to develop and utilize one
of its best assets.

Presented l)y iillo in the absence of tlie author.
Section adjourned al 5 o'clock p. m.

SECOND SECTION

The Second Section did not convene on the afternoon of the first day
on account of the desire felt by its members to participate in the meeting
of the Paleontological Society.

TITLES AND ABSTRACTS OF PAPERS PRESENTED BEFORE THE THIIJD SECTION

AND DISCUSSIONS THEREON

The Third Section convened about 3.35 o'clock p. ni., with IT. P. dish-
ing in the chair and Ernest Howe serving as secretary. The section took
up the reading of papers in Group C as follows : Petrologic, Mineralogic,
and Economic.

PRE-CAMBlilAN IGNEOUS ROCKS OF THE PENNSYLVANIA PIEDMONT ^

BY F. nASCOM

(Abstract)

Pre-Cambrian igneous rocks of the Pennsylvania Piedmont are pegmatite,
rhyolite, granite (granltite, hornblende granitite. hornblende granite), grano-
dioritp, quartz diorite, andesite. quartz norite. quartz gabbro. gabbro (norite.
augite gabbro, anorthosite, hornblende gabbro), basalt, pyroxenite (webstcr-
ite), and peridotite.

The application to lliem of the quantitative .system of classification shows
(rt) that the.v form :i rcui.iik.iljly cnntiinKnis scries from ;i pors.ilic to ;i jicr-

* By prrmi.ssioii nf (hi> I liicdor nf (ho I'. S. Geological Siirvry.

82 PROCEEDINGS OF THE r-HILADELPHIA MEETING

femic magma, and (b) that a striking uniformity exists tlirougtiout the series
ill rangs and subrangs.

The uniformity denotes consanguinity ; the distribution, through all the
classes (class 1 to class 5), magmatic differentiation. No alkaline differenti-
ates are found ; neither feldspathoid nor soda-bearing pyroxenes are original
( onstituents of any type. The differentiated magmas are almost without ex-
ception alkalicalcic. docalcic or percalcic, and presodic.

In areal distribution the acidic types are most abundant and the gabbroid
types second in abundance ; the most acidic and the most basic differentiates
are least widely distributed.

The possible origin of a peculiar granodiorite through marginal assimilation
by the gabbro of the acidic gneiss into which it intrudes was discussed, and
some features of the anorthosite occurrence were presented.

Presented by title in the absence of the author.

MAGMATIC ASSIMILATION
BY F. BASCOM

(Ahstract)

Near Strathcona, Vancouver Island, Canada, lime and magnesian silicates
(epidote, chlorite, serpentine) have been developed in a diorite batholith to a
distance of 1,400 feet from an included lens of limestone (40 to 50 feet wide) :
750 feet south of the lens small irregular masses of limestone are included in
the altered diorite, while three-fourths of a mile to the south the diorite is
of a normal character. The rocks have been named the Sutton limestone and
AYark diorite by C. H. Clapp (Memoir No. 1.3, Can. Geol. Survey).

Read by title, drawings being on view in exhibition room.

HYPERSTHENE SYENITE (AKERITE) OE THE MIDDLE AND NORTHERN BLUE

RIDGE REGION, VIRGINIA

BY THOMAS L. WATSON AND JUSTUS H. CLINE

(Abstract)

Several seasons of field work by the Virginia Geological Survey in the middle
and northern parts of the Blue Ridge and adjacent portions of the Piedmont
plateau in Virginia have shown the dominant igneous rock of- the granitoid
type to be a quartz-bearing pyroxene syenite, the important facies of which is
similar in composition to the akerites of Norway described by Brogger. This
igneous mass, of which pyroxene syenite is the chief type, probably represents
a pre-Cambi"ian batholithic intrusion exposed more or less continuously for a
distance of 150 miles in a belt up to 20 miles or more in width.

Differentiation of the syenite mass has given rise to a variety of related
rocks, some of which are of unusual types. Microscopic study of many thin
sections shows the important minerals of the syenite in descending order of
abundance to be soda-lime feldspar (albite to andesine-Iabradorite, chiefly

ABSTRACTS OF PAPERS 83

aiidesine), potash feldspar (orthoclase and microcline), pyroxene (hypersthene
and some augite, diallage in part), quartz, hornblende, biotite, and usually
considerable apatite and ilmenite or titanit'erous magnetite. Hypersthene is a
I)rominent mineral in each rock member of the series, and the presence of it
together with that of abundant apatite and titaniferous iron oxides in places
establishes the close petrographic relations of this large syenitic body to tlie
smaller one of high phosphorus and titanium-bearing rocks of the Amherst-
Nelson counties rutile district described in Bulletin III-A of the Virginia Geo-
logical Survey.

Complete chemical analyses have been made of representative specimens of
the syenite collected from a half dozen or more different localities within the
Virginia region. The norms calculated from these analyses show that the
rocks are mostly alkalicalcic, belonging to tonalase, and of the sudipotassic
subrang harzose. Two analyses yielded norms which fixed the position of the
rock as amiatose and dacose, respectively, in the quantitative system.

Presented l)y title in the al)sence of the autlior.

PYRRHOTITE, XORITE, AXD PYROXEXITE FROM LITCHFIELD, CONNECTICUT

BY ERNEST HOWE

(Abstract)

Norites and pyroxenites from I.itch field County, Connecticut, are shown to
contain pyrrhotite and chalcoi^yrite as constituents of magmatic origin. Two
periods of crystallization are recorded, the separation of the sulphides, to-
gether with hornltlende, biotite. and plagioclase. having taken place after oli-
\'ine and i)yroxeue had crystallized and had suffered partial resorption. The
late appearance of the sulphides in the crystallizing magma is attributed to
the pre.sence of mineralizers which held the sulphides in solution. The rocks
are compared with those associated with the copper-nickel deposits of Sudbui-y,
Ontario.

I'resented in ahstract from notes.

Remarks were iiindc liy Messrs. W. TT. Emmons and reply made by the
anthor.

SOME EFFECTS OF PRESfiURE ON ROCKS AND MINERALS
BY JOHN JOHNSTON ^

{Ahstract)

A general discussion of the .'ivailablc exiuM-liut'iital evidence beai'iiig on tlie
influence of pressure on the forma tioii and behavior of rocks and minerals and
of the conclusions which may juslitiaiily be drawn from this evidence.

I'resentcd ill absl raci IVoiii notes.

Iiilrixliici'd hy Arlliur I,. Day.

VII— Bull. Geol. Sue. Am.. Vol. '_'(;. IHU

84 PROCEEDINGS OF THE PHILADELPHIA MEETING

Discussion

Dr. C. N. Fenner pointed out that as regards the question of a eutectic com-
position of pegmatites several points must be held in mind. In the first place,
the solutions from which pegmatites have been deposited undoubtedly con-
tained not only water, but other volatile ingredients, each of which would by
its presence affect the temperatures at wliich tlie nuartz and feldspar would
crystallize out, and also the relative inopoitions in which the two would ap-
pear. Moreover, whei-e more than one land of feldspar molecule is present the
relations become much more complicated because of the formation of solid
solutions, and the .simple eutectic relations no longer hold.

Mr. J. P. WiNTBiNGHAM asked whether a graphic intergrowth was not to be
talien as indicating a eutectic.

Mr. Johnston in reply pointed out that tliere appears to be no character-
istic eutectic structure in silicate systems similar to that well known in metal
systems, though such eutectic structure may appeal' in silicate systems con-
taining \olatile components, this being a point on which there is not laboratory
evidence at present. Again, that though the eutectic is the temperature at
which the last of the mixture solidifies, much of the material will in general
have crystallized out before ; that the eutectic is merely a special point on the
curve, and that in all probability its importance is not so great as has been
supposed, especially in view of the frequent occurrence of solid solutions.

Further remarks were made by W. Cross, W. H. Emmons, and J. E.
Wolff.

PRIMARY CHALCOCJTE IN THE FLUORSPAR VEINS OP JEFFERSON COUNTY,

COLORADO

BY HORACE B. PATTON

(Abstract)

Several sharply defined veins, mainly of fluorspar, but also carrying consid-
erable amounts of chalcocite and of other sulphides, have been opened in Jef-
ferson County, Colorado. The veins have been worked for fluorspar and, to a
lesser extent, for chalcocite. These are clean-cut fissure veins in Archean
schist and gneiss, occurring in close proximity to granite intrusions. The
association of fluorspar and chalcocite is unusual, and in this case the condi-
tions .seem to indicate that the chalcocite is of primary origin.

Presented in abstract extemporaneously.

RECENT REMARKABLE GOLD "STRIKE" AT THE CRESSON MINE, CRIPPLE

CREEK, COLORADO

BY HORACE B. PATTON

(Abstract)

A recent very remarkable "strike" of gold telluride ore has been made in
the Cresson mine at Cripple Creek. The conditions are very unusual for this

ABSTRACTS OF PAPERS 85

camp : first, because of the extraordinary richness and extent of the deposit ;
second, because of the depth of the ore shoot below the surface ; third, because
of very interesting geological conditions that are likely to throw considerable
liglit on the origin of these tellurides. At a depth of 1,265 feet a large cham-
ber was struck on November 25, 1914, the walls of wliich were heavily impreg-
nated with calaverite. The chamber was lined with a white porous material
that consisted mainly of celestite and that ran from $10,000 to $16,000 to the
ton. Evidences point to the chamber being part of a watercourse rising from
considerable depth.

Presented in abstract extemporaneously.

Discussion

Dr. C. N. Fenner inquired whether there was not some similarity between
the general relations of the main ore-pipe at tlie Cresson mine as described by
Mr. Patton and those at the old Bassick mine in Custer County. In the latter
also there was a main ore-pipe of elliptical cross-section filled with a breccia,
whose pebbles were crusted with ore minerals.

Messrs, Whitman Cross and H. B. Patton took part in the discussion.

PLATINUM-OOLD LODE DEPOSIT IN SOUTHERN NEVADA
BY ADOLPH KNOPF

(Abstract)

The ore of the Boss gold mine in the Yellow Pine mining district, Nevada,
has recently been shown to contain considerable platinum. The deposit occu-
pies a vertical zone of fracturing in dolomite of Carboniferous age. The
gangue consists mainly of fine-grained quartz, but streaks of bismuth-bearing
plumbojarosite (a hydrous sulphate of lead and ferric iron) are found carry-
ing as high as 111 ounces gold, 99 ounces platinum, and 16 ounces palladium.
Some 600 feet from the mine is a small intrusion of granite porphyry, but no
basic intrusives occur ; in fact, none are known to occur in the whole district,
which is the most productive lead and zinc district in Nevada.

Eead in full from manuscript.

Eemarks were made by Prof. AV. H. Emmons.

OROANIC ORIGIN OF SOME MINERAL DEPOSITS IN UNALTERED PALEOZOIC

SEDIMENTS

BY GILUEKT VAN INCiEN

{Ahstnirl)

The common association of galena, sphiilcritc, and some other minerals with
reef deposits of early I'alco/olc age was desci'ibed, and a suggestion was
otfert'd that the i-ecf-buildiiig organisms were directly responsible for tlu> pri-
mary concentration of these minerals, and that deposits of the Joplin, Mis-

86 PROCEEDINGS OF THE PHILADELPHIA MEETING

souri, and the Galena limestone type of Wisconsin and the Fenorite of the
Mississippi Valley have had such au origin.

Eead in full from maiinscri]:»t.

Discussion

Mr. John Johnston : I understand that the hlood of oysters and similar
animals contains copper, this copper heing to some extent analogous to the
ii'on in the hiemoglohin of human blood.

Dr. Frank R. Van Hokx : I have been much interested in Professor Van
Ingen's paper, which has treated a new subject from a paleontologic physio-
logic standpoint. For some years I have been of a similar opinion, which was
arrived at on account of cliemico-minera logic reasons. The association of lead
and zinc ores with dolomitic limestones is well known, from various parts of
the Mississippi Valley as well as certain places in (Germany. The association
of lead with limestones can be explained by the isomorphism of the carbon-
ates of calcium, barium, strontium, and lead in the minerals aragonite. wither-
ite, strontianite, and cerussite. The association of zinc with limest(mes can be
explained by the isomorphous calcite group, which consists of calcite, dolo-
mite, magnesite, siderite, rhodochrosite, and, lastly, smithsonlte, which is zinc
carbonate. Doctor \'an Ingen's reasons for assuming that the tissues of vari-
ous mature animals absorb metallic salts will hold equally true for their shells
and other hard parts which are secreted by the soft parts, and it is the hard
parts which originally formed the limestone beds. It Is very clear that there
must have been a chemical rearrangement of compounds, since the metals are
found now as sulphides and sulphates. We know that most limestone has
been more or less dissolved and recrystallized. In this rearrangement the car-
bonates of the metals may likewise have been dissolved and subjected to re-
ducing solutions which have resulted in galena, sphalerite, barite, and celestlte.

Further remarks were made by Messrs. T. L. Watson and W. H.
Emmons.

The section adjourned at 5.1 T) o'clock p. m.

PRESIDENTIAL ADDRESS

At 8 o'clock p. m. the Society convened in the lecture hall of the
Academy of Natural Sciences and listened to the reading by Vice-Presi-
dent W. Lindgren of an abstract of the address of retiring President
George F. Becker, entitled

TSOfiTASY AND RADIOACTIVITY

Publislied as pages 171-204 of this volume.

The address was followed by the complimentary smoker given in honor
of the Geological Society of America and the Paleontological Society by
the local members of the former organization.

abstracts of tapers 87

Session of AVednesday, December 30

The Society convened at 9.30 o'clock a. m. in general session, First
Vice-President W. Lindgren in the chair.

report of auditing committee ^

The Auditing Committee begs to report that they, have examined the
papers and vouchers of the Treasurer and find them to be correct and in
good order.

The investment securities Avill be examined at a later date.

J. M. Clarke,
H. L. Fairchild,
For the Committee.
The report was accepted.

The printed report of the Council was taken from the table and, on
motion, accepted.

titles and abstracts of papers presented in general session and

discussions thereon

REVISION OF PliE-CAMliRIAN CLA.SSIFWATIOy IX ONTARIO
BY WILLKT G. MILLER AND CYKIL W. KNIGHT

(Ahstract)

I>uriii{j the past decarlo the authors have been piifraged in detailed work on
pre-Cainhriau areas in various parts of the Province of Ontario. The results
of tliis work, and that of otlier investij,'ator.s, have made apparent the necessity
for revising the age classification of tlie pre-Cambrian rocks, particularly in
the use of the terras Huronian. Laurentian. and others. The following classi-
fication and nomenclature have therefore been adopted by the Ontario Bureau
of Mines:

Keweenawan,

Unconformity.
Ammikean.

Under this heading tlie authors i)lace not only the rocks that have
heretofore been called Animikie, biit the so-called Huronian rocks
of the "classic"' Lal^e Huron area and the Cohalt and Ramsay Lake
series. Minor unconfonnities occur within the Animikean.
QrenI unconformity.

' I'nflfi- (la(p of I'Vhi-miry 11. 101.";. lOflwanl H. Miitlicwn rcpnrls llinl. artlriB as a mom-

lii'f of ilic Aiulilinj: ComtniKi f \\\r Soclclv. he cxamliicd llio Soc|pty".s srciirlflrs In

tlie hiiiirls of the 'I'rfiisiircr antl found llii'iii to ln' as Usicd in (ho Troasiirpr'.s report
under date oi December 1, 1014.

88 PROCEEDINGS OF THE PHILADELPHIA MEETING

(Algoman Granite and Gneiss.)

Laurentian of some authors, and the Lorrain granite of Cobalt, and
the Killarney granite of Lake Huron, etc.
Igneous contact.

TiMISKAMIAN.

In this group the authors place sedimentary rocks of various localities
that heretofore have been called Huronian and the Sudbury series
of Coleman.
Great unconformity.

There is no evidence that this unconformity is of lesser magnitude
than that beneath the Animikean.
(Laurentian Gbanite and Gneiss.)

Igneous contact.
Loganian.

Grenville (sedimentary), Keewatin (igneous).

The authors have found the Keewatin to occur in considerable volume
in southeast Ontario and have determined the relations of the
Grenville to it.

Investigations by the junior author during 1914 have shown that certain
rocks of the "classic" Huronian area of Lake Huron, the "Thessalon green-
stones," that heretofore have been placed with the Keewatin, are of much
later age, being in intrusive contact with the Animikean, as defined in the
above table.

Presented in abstract extemporaneously by the senior author.

Discussion

Prof. H. P. CusHi.xG stated that the proposed classification was easily ap-
plicable in the Adirondacks, and that he had for some time felt that the
Grenville was most probably to be correlated with the Keewatin. because of
its similar relationship to the oldest granite invasion, the Laurentian. That,
in Professor Cushing's opinion, in pre-Cambrian correlations the wide-spread
intrusions furnish the safest guide ; that in all likelihood the later intrusive
masses of the Adirondacks are to be correlated with the Algoman.

Further remarks were made l)y Messrs. W. S. Bayley and \X. Lindgren,
and reply was made by Dr. W. G. Miller.

NORTH AMERICAN CONTINENT IN UPPER DEVONIC TIME
BY AMADEUS W. GEABAU

(Abstract)

The history of North America in the Upper Devonic has been worked out in
some detail on the basis of physical .stratigraphy combined with paleontology.

At the opening of the Upper Devonic marine waters were much restricted
in North America, the greater part of the United States being exposed to
active erosion of the previously deposited Hamilton or earlier formations, as

ABSTRACTS OF PAPERS 89

indicated by disconformities. The Tully-Genesee Sea was restricted to central
New York, but extended northward over Canada. Appalachia, Atlantica (the
Old Red Continent), and Mississippia were the chief continents. The evidence
liointing to the gradual southward transgression of the sea over the eroded
lands is clear. Three open marine water bodies existed throughout Upper
Devonic time, each with their distinctive faunas : (1) The northern, extending
from central New York across Ellsmere Land to the Urals; (2) the western or
North Pacific, extending across part of Alaska ; (3) the eastern or Atlantic.
The latter entered the interior by way of a narrow strait between Appalachia
and Atlantica, permitting the periodic invasion of the Atlantic or Tropido-
leptus fauna. There may have been a fourth South Pacific water body ex-
tending into Nevada, but this is less certain. Three principal river systems
are recognized in the lowland of Mississippia. These have furnished the black
mud for the black shales which were deposited in embayments of diminished
salinity. The eastern or Genesee beds are restricted to New York and the
States just south. The base of the black shale of Ohio, Michigan, and Canada
is younger than Genesee, as shown by stratigrapliic and paleontologic evidence.
The great fish fauna of these shales is shown, by its occurrence and distribu-
tion, to be primarily the fauna of these sluggish rivers projected at intervals
into the brackish water of the embayments. The land flora of Mississippia
is also pre.served in these shales. The rivers of Appalachia and Atlantica also
had their fish fauna, but these were of diffei-ent types, their smaller size
adapting them to these torrential streams. With them occurred the survivors
of the Eurypterids, which also inhabited the rivers of the Paleozoic lands.
The flora of Appalachia and Atlantica is likewise largely distinct from that
of Mississippia. The deposits made by these rivers were partly preserved as
sandy deltas and alluvial fans.

Presented in al)straet extemporaneonply.

Discussion

Prof. C. S. Prosser stated that in his belief the chart by Professor Grabau
showed in general the changes in the character of the sediments of the Ohio
shale in northern Ohio to the equivalent ones in northwestern Pennsylvania
and western New York.

In Ohio there is a black shale in the Mississippian (called the Sanbury)
separated by the Berea grit and Bedford formation from the subjacent Ohio
shale. .\s these formations are followed across the Ohio River in Kentucky
the Berea and Bedford rapidly thin until when about one-half the distance
across the State the Ohio and Sanbury shales are separated by only a few
inches of deposits representing the Berea and Bedford. It ai»pears probal)le
that fartlier south these two black shales come together and belong in both
Devonian and Mississippian age.

Professor Prosskr called attention to the extension of the Sherburne .sand-
stone (<> tlie sandstone to the east in New York than indicated by Professor
Gral>an"s diagram. He (Professor Prosser) has Iniced the Sherimrne sand
stone from the typical region in tlie Chenango Valley eastward across th»>
Unadilla, Su.squelianna, and Schoharie valleys, and then, after the change in

90 PROCEEDINGS OF THE PHILADELPHIA MEETING

strike of the Paleozoic formations of eastern New Yorl£, southward on the
eastern side of the Catskill Mountains.

lieiiiarks were made )jy Prof. H. P. Cashing, and reply by the author.

SYMPOSIUM ON THE PASSAGE FROM THE JURASSIC TO THE CRETACEOUS

Tlie Society tlieii merged into joint session with tlie Palcontologieal
Society for the "Symposium on the passage from the Jurassic to the
Cretaceous." The speakers and their contributions were as follows :

Willis T. Lee : The Morrison ; an initial Cretaceous formation.
Charles C. Mook : Origin and distrilnitiou of the Morrison.
R. S. Lull : Sauropoda and Stegosauria of the Morrison compared with
those of South America, England, and Eastern Africa.
E. W. Berry : The Paleobota nic CAidence.
T. W. Stanton : The invertebrate fauna of the Morrison.

The a1)s1i-acts and discussions of Ihosc pajiers will be found in the
Proceedings of the Palcontologieal Society in this volume.

The general session adjourned at 12.35 o'clock p. m.

TITLES AND ABSTRACTS OF PAPERS PRESENTED BEFORE THE FIRST SECTION

AND DISCUSSIONS THEREON

The First Section met at 2.30 o'clock, with John M. Clarke in the chair
and D. W. Johnson serving as secretary.

TYPE OF RIFTED RELICT MOUNTAIN. OR RIFT-MOUNTAIN
BY JOHN M. CLARKE

(Abstract)

The Table Rolante, near Perce. Province of Quebec, is an uplifted relict of
the Bona venture (Devono-Carboniferous) conglomerate, bounded by sheer
sides and resting almost horizontally on the upturned older paleozoics. It is
believed that this rolling elevated plateau has' been abruptly isolated by un-
dermining through solution of the limestones on which it rests ; that the sheer
walls are not due to faulting, but to rifting along joint planes, and that by
persistence of this process successive blocks of large size have sunk to lower
levels.

Presented in abstract from notes.

Discussion

Mr. William J. Miller : During the summer of 1914 there came under my
observation an example of rifting, the principle of which is very similar to

ABSTRACTS OF I'APERS

that so well described liy Doctor Clarke. In the Adirondacks, beautifully
stratified (Jrenville rocks, some liuiidreds of feet thick, dip westward at 55°
and rest against Chinniey Moun-tain, consisting of syenite which rises nearly
3,000 feet above the surrounding country. On one summit of the mountain a
block of Grenville one-(iuarter mile long has broken away fi'om the main mass,
leaving a rift 200 to 300 feet wide and 250 feet deep, with very steep walls.
The rifted block dips 20° northeastward. It broke away along a joint plane,
due to solution of underlying calcareous strata, in a manner similar to that
explained by Doctor Clarlie.

EVIDENCE OF RBCEST HUHSIDENCE ON THE COAXT OF }LUNE

BY CHARLES A. DAVIS

{Abstract)

A few weeks during the summer of 1014 were spent on the shores of Dam-
ariscotta River and the adjoining bays and inlets, during which opportunities
were found to study a rocky coastline for evidences of recent subsidence.

Three general classes of such evidence were found.

(1) Dead anil <lying trees and other fresh-water plants
at and below the high tide level on all kinds of
shores.

(2) Forest beds containing stumps of trees outside
the present shoreline down to and below tide
level.

{?>) Salt marshes with fresh-water beds of peat be-
low them.

A. Botanical.

B. Physiographic. .<

C. Historic <

' (1) The present form of the rock coast of the region.
(2) The general existence of ancient weathering on
the rocks extending from above high tide level
to below low water.

(1) Existence of walls, wliarves, and other structures
below high tide level.

(2) Closing of springs formerly used l)y settlers by
sea-deposited debris.

The |);i|)ci- i-ecorded sonio of tlie more iiii[)(iiiaiil fiuis disc-oxci-iMl and
described tlicii' occiiiTcnce. ,

Presented in abstract extemporaneoiisl}'.

Discussion

Mr. ,ToHN T/. PiTcii : Several of the trees and stumps which were shown as
having been invaded Ity salt water occur on relatively steep slopes, covered,
according to the accounl. by (ill. I slmuld like to .isk wbetlier creep has been
eliminated as .i cnnsc of (he ;ipparenl rise of the water level. Conditions seem
iMvondile for it here. and. moreover, sevenil of the trees show .-i down bill
juclination near the bast>, which is a very cliaracleristi<- result of creep. A

92 PROCEEDINGS OF THE PHILADELPHIA MEETING

slow creeping: of soil and trees down the slopes might well account for the
phenomena shown.

Prof. D. W. Johnson analyzed the evidence presented by Doctor Davis and
concluded that it could not properly be regarded as supporting the theory of
recent coastal subsidence, for the reason that all the phenonjena described by
the author are frequently produced by normal retrogression of a vertically
stable shoreline under wave attack and ma.v be observed on lake shores where
no changes of level are involved.

Fiii'ilicr rcmai-ks were made )iy Messrs. H. Ami and Joseph Barrell.

BASIC ROCKS OF RHODE ISLAND: THEIR CORRELATION AND RELATIONSHIPS

BY A. C. HAWKINS AND C. W. BROWN

(Absti-act)

Rhode Island as a whole is underlain by a great granite batholith, now
sheared, of uncertain age, but of high antiquity, together with other sheared
granite types lying to the east and west, of alleged different ages. In these
stocks are found remnants of metamorphosed rocks, quartzites, quartzitic horn-
blende, and biotite schists of so-called sedimentary or comliined sedimentary
and igneous origin. In addition there appear several gabbroid stocks, more
()!• less changed, but rather basic in type, which may in part be pre-granitio.
IMoreover, there appear trappean intrusions of four distinct types, such differ-
ent ones as minette and Triassic diabase dikes. Of these four types, two are
perhaps rather closely associated in age, but the others are more remote from
each other.

From the field relations and from analyses of similar rocks, which show
silica too low and lime and magnesia too high for sediments, it would seem
that the so-called sedimentary biotite schists are distinctly of igneous contact
origin, resulting from the intrusion of granites into earlier basic rocks more,
or less schistose. From the evidence along the borders of the new Carbonif-
erous basin, the Woonsocket basin, extending southward from the Norfolk,
it would appear that some of the granitic stocks asserted to be post-Carbonif-
erous are really pre-Carboniferous in age.

Read in full from manuscript.

Discussion

Mr. Sidney Powers asked why the authors thought the Sterling to be pre-
Carboniferous.

Mr. Hawkins replied that they had found that the Woonsocket basin sedi-
ments (presumably Carboniferous) rested unconformably on granites of Mil-
ford age on its borders and contained blue quartz grains evidently derived
from the latter. Tliey also found that the structure of the granite gneisses
on the borders indicated a possible anticline on whose eroded crest the sedi-
ments were deposited. In response to Mr, Powers's request for proof of the
intrusive nature of Westerly granites into Sterling granite gneiss, Mr. Haw-
kins stated that such contacts had been exposed in quarries at Bradford,
Rhode Island.

ABSTRACTS OV PAPERS 93

Prof. C P. Berkey suggested that much of the larger curving gneissie struc-
ture observed by Messrs. Hawkius and Brown might have been due to original
flow structure.

Mr. Hawkins cited the observations of Loughlin (Bulletin 492. U. S. (ier)-
logical Survey), wlio found crushing in tlie grains of the Sterling, and said
that he and Professor Brown had observed shearing in included fragments in
tlie granite, such shearing being apparently post-inclusion.

ACADIAN TRIASSW
BY SIDNEY POWERS '

{Abstract)

The Acadian Triassic is exposed on both sides of the Bay of Fundy. In
New Brunswiclv the Triassic occurs on the west side of the Island of Grand
Manan, and also at Split Rock (near Gardner's Creek), Quaco. Martin Head,
and Waterside. In Nova Scotia the Triassic borders Minas Basin and tlie
Bay of r^nidy.

The Newai'k group is divided into the following formations, whose thick-
nesses are estimated:

Feet

Scots P.ay formation 2,5- (2,(H)0? )

North Mountain basalt 80O- 1,000

Annapolis formation :

Blomidon shale 500- 1,000

Wolfville sandstone 2,000- 2,500

3,325 6,500

luterbedded with the Annapolis formation, approximately at the horizon ot
the Blomidon shale, are the Five Island volcanics, consisting of tuffs, agglom-
erates, and basalt flows.

'I'1h> Scots Bay formation consists of calcareous gray to green siindstoiie aixl
shale, carrying fish remains. It rests directly on the North Mountain basalts
and is conformable with them. The formation is preserved in small synclines
at Scots Bay. The North Mountain basalt consists of flows of varying thick-
ness. At Cape D'Or, in a 556-foot flow, evidence of gravitative differentiation
of the feldspar and augite and of variation of both grain and spccitii- gia\iiy
with depth have been found. The Annapolis formati<tn is composed nf red-
beds, and in the sandstones at Martin Head plant remains have been found.

The structure of the Acadian Triassic comprises monodinal tilting toward
the northwest and gentle folding. Faulting is abundant, but most of the faults
have a small displacement. The major faults are at the ba.se of liie Cobe(iuid
Mountains, on the north side of the Triassic around Minas Basin, and on the
northwest side of the New T'.runswick areas. The honk in Xoitli Monnlain,
fioin C.-ipc P.loiiiiijoii to (';ipc Si)lit, is ii pitching svncliiic. cut olV on Mm- riorlh
l>y a fault. Another ini|ir>rtiitit syiicliiic is foiiiHl at <,»ii;ico. New i;nin<u ii-i^.

Presented in lull ('\lcin|Miraneously.

'Introduced by U. A. I'al.v.

94 PK0CEEDING8 OF THE PHILADELPHIA MEETING

Discussion

Dr. C. N. Fenner inquired as to tlie character of tlie contacts in those ex-
posures where the basalt sheets rest directly on older rocks not belonging to
the Triassic, especially as to whether the basement I'ocks were absolutely bare
or wliether tliere was some small amount of detrital material between the
basalt and the floor on wliich it rests.

Prof. J. VoLNEY Lewis : Some of the basalt sheets in the Newark formation
of New Jersey are undoubtetlly composite, but the evidence on \\-hich successive
flows are distinguished is not in every case clear cut and decisive. In some
places a platy jointing or bedlike parting is very deceptive. I sliould like to
ask Mr. Powers on what basis he was able to separate the members of the
multiple basalt which lie has described and shown to us from the Bay of
Fundy.

Dr. John M. Clarke stated that he believeil the term Caledonian should l>e
used in preference to Shiclishock and Brunswickian as a name for the mid-
Devonic disturbance.

GEOLUGICAL UltiTOlxy OF THE BAl' OF FUXDY

{Abstract)

The Bay of Fundy lies along orographic axes which appear to liave existed
since the beginning of the Cambrian period. Transgressions of the seas in
Cambrian, Ordovician, Silurian, and Lower Devonian times are recorded in
small remnants of sedimentary rock, but there is a lack of evidence to sliow
that tlie sea at any of these times occupied the entire Fundy region.

A disturl)ance of Middle Devonian age folded the Lower Paleozoic rocks
with a trend similar to that of the pre-Cambrian axes. Minas Basin was
formed as a structural unit at this time by the folding of the Cobequid Moun-
tains. The Nova Scotian granites, and probably the igneous rocks of the
Cobequids. were intruded at tliis time

LHiring a portion of the Mississippian perio<l. sedimentation continued in the
northern part of the Fundy region. In the I'eunsylvanian period, the I'nion-
Riversdale and Mispec-Little River formations were deposited along the axes
of Minas Basin and a portion of the Bay of Fundy. After the Millstone grit
and the Coal Measures had l)een deposited nortli of the Cobequid I\I(nnitains,
another disturbance folded these Lower Pennsylvanian sediments.

The period of deformation in mid-Pennsylvanian (ConemaughV) time is
correlated with the Armorican-Variscan disturbance of lOurope. as the Middle
Devonian disturbance is correlated with the Caledonian of Europe. In the
Armorican-Variscan disturljance tlie Union Riversdale and Mispec-Little River
sediments were greatly folded, wliile the Coal Measures, north of the Cobe-
quids, were not greatly disturbed. The main axis of folding was east-west
from Saint John through Truro.

Following the mid-Pennsylvaiiiaii disturliiiiiic came activ(> erosion and the
deposition of the ITj^per Pennsylvanian-Permian New tilasgow conglomerate

1 Introduced by R. A. Daly.

ABSTRACTS OF PAPERS 95

north of the Cdbequids and of its equivalent, the Carboniferous conglomerate,
south of the Cobequids, along the axis of Minas Basin.

At the close of deposition, with a slight disturbance in the Permian, a pene-
plain was developed in the Fund.\- region, and on the surface of this peneplain
the Tria.ssic sediments were laid in a shallow geosyncline. Block tilting and
faulting closed the Newark stage and changed the geosyncline into a region of
erosion. During the long period of erosion two peneplains have probably been
developed and uplifted by middle and late Tertiary time.

Presented in full extemporaneously.
Eeraarks were made by Di'. W. C. Alden.

The section adjourned.

TITLES AXD ABSTRACTS OF PAPERS PRESENTED BEFORE THE SECOND SECTION

On the conclusion of the presidential address of the Paleontological
Society, at 3.30 o'clock p. m., the reading of papers of Group B was com-
menced, with Vice-President Van Ingen of the Paleontological Society
presiding.

ALEXANDRIAy ROCKS OF NORTHEASTERN ILLINOIS AND EASTERN

WISCONSIN

BY T. E. SAVAGE

(Abstract)

The early [Silurian strata in northeastern Illinois and eastern 'Wisconsin
were described and their fossils listed and discussed. The so-called "Clinton
Ir(jn ore" bed was shown to belong in the Ordovician system as the upper
member of the Ma(iuoketa of this region. The lower part of the Mayville
limestone of Wisconsin contains an Edgewood fauna and is considered the
e(iui\ak'iit in time of the Kdgewood formation of Illinois and Missouri. The
upper strata of the Mayville limestone furnished fossils characteristic of the
fiexton Creek (Bra.ssfield) limestone of Illinois and are regarded as repre-
senting a nortliward extension of that foi'iuation.

liead in lull from manuscript.

Tiie paper was discussed by Messrs. TTIrich and Oi-abau, with re])ly by
the author.

OLENTANGY SHALE AND ASSOCIATED DEPOSITS OF NORTHERN OHIO

BY CLINTON R. STAUFFER

(Ahfilnict)

A recent study of the section and fossils of the Olentangy shale to tiie south
and east of Sandusky, Ohio, indicates that it represents tlie lnwer part of tiie
Hamilton i)eds of Ontario. Tlie I'rout limestone, whicli lies immediately be-

96 PROCEEDINGS OF THE PHILADELPHIA MEETING

neuth the Huron shale in that region, represents tlie Encrinal limestone of the
Thedford, Ontario, region and probably also the similar layer along EighteeJi-
mile Creek in New York. The thinning in the Hamilton beds from Thedford
southward to Sandusky is thei'efore either l)y disappearance of the upper por-
tion of the Hamilton, thus allowing the Huron to rest directly on the Encrinal
limestone, or the lower part of the Huron shale itself must represent the upper
Hamilton beds. Indications to the southward from Sandusky are that the
Huron is continually lapping over on older beds, while the fossils in the lower
Huron south and east of Sandusky indicate that this deposit is about the age
of the black shale at Kettle Point. Ontario. The Huron shale, therefore, rests
unconformably on the Encrinal or Prout limestone of northern Ohio and the
whole upper Hamilton is wanting.

Presented by title in the aljsence of the author.

DIASTROPHIC IMPORTAlSlCE OF THE Vy CONFORMITY AT THE BASE OF THE

BEREA SANDSTONE IN OHIO

BY H. P. CUSHING

(Abstfact)

By description of the character of the unconformity at the base of the Berea
sandstone in Ohio the attempt was made to show that the break between the
Berea and the underlying Bedford shale must be a trifling one, involving no
great lapse of time, and hence of slight diastrophie importance.

Eead in full from manuscript.

Discussed by Messrs. David White, Charles S. Prosser, and A. W.
Grabau. The discussion was discontinued so that the papers by Messrs.
Ulrich and Grabau could be considered together with tliis one.

KINDERHOOKIAN AGE OF THE CHATTANOOGAN SERIES

BY E. O. ULEICH

iAl)Stract)

Recent discoveries in Tennessee and Missouri tend to show that the shale
and sandstone formations comprised in the Chattanoogan series, as defined by
the author in 1912, are really younger than was then supposed. Judging from
the data then in hand, the Chattanoogan was wholly removed from the De-
vonian system and placed as a new series at the base of the Waverlyan (Lower
Mississippian) system. With the new evidence, it now appears that the Chat-
tanoogan is approximately contemporaneous with the Kinderhookian series of
the Mississippi Valley. The principal data on which this conclusion is based
are as follows :

1. In Tennessee and Kentucky the Chattanoogan shale is commonly suc-
ceeded by the New Providence shale. At many other places in these States,
particularly in Tennessee, the top of the Chattanooga is in contact with the
Fort Payne chert. At a few places, however, a third formation — the Ridge-

ABSTRACTS OP PAPERS 97

top shale — rests on the black shale of the Chattanooga. Of these three post-
Chattanoogan formations the Rldgetop shale is the oldest, the New Providence
shale next younger, and the Fort Payne chert the youngest. The last is of
the age of the Keokuk limestone of the Mississippi Valley. Locally its basal
part may include beds corresponding to late Burlington. The New Providence
shale corresponds in age to the Fern Glen formation of Missouri and Arkansas.
Weller and others classify the Fern Glen as late Kinderhookian, but the author
regards it as Lower Burlington, or at least as post-Kinderhookian ; hence, early
Osagian.

So long as the Chattahoogan was regarded as Devonian, and therefore as
distinctly older than the Kinderhookian series, the Ridgetop shale was assumed
to be an early Kinderhookian deposit. Fossil evidence from the concerned
beds was both scanty and of undetermined significance. In the past two or
three years, however, reasonably good collections of fossils have been made
fi'om three zones in the Ridgetop shale. These fossils prove conclusively that
the formation, instead of being early Kinderhookian in age, in fact represents
fi very late fades of this epoch.

2. The contact between the Chattanoogan and succeeding formations gen-
erally indicates a break in sedimentation, except in those sections in which
the Ridgetop shale is developed. In these no evidence of discontinuity has
been discovered. As the fossils of the Ridgetop shale indicate a late Kinder-
hookian age, this continuity of deposition properly leads to the inference that
the underlying black Chattanoogan shale also is, at least in part, of early
Mississippian age.

3. Black shale containing Sporangites, and evidently of Chattanoogan age,
was discovered during the past year by Prof. Stuart Weller in Sainte Gene-
vieve County, Missouri. This bed of shale overlies the Glen Park limestone,
which, farther north, overlies the Louisiana limestone. Faunally and litholog-
ically the Louisiana corresponds best with an upper member of the typical
Kinderhook sections at Kinderhook, Illinois, and Burlington, Iowa. This
transgressing, presumably upper part of the Chattanoogan, is thus proved to
be late Kinderhookian in age.

4. South and west of Irvine, Kentucky, the Chattanooga shale is an indi-
visible stratigraphic unit. The upper part of this unit Is generally concedetl
to be of Mississippian (Sunbury) age. We now learn that the top of the
lormation c-orresponds in position approximately to the top of the Kinderhook.
and is therefore much younger than the base of the Mississippian in the
Mississippi Valley. In seeking to fix the latter boundary in Kentucky and
Tennessee, we may follow the principle of drawing the line at the first impor-
tant break in sedimentation beneath the part of known late Kinderhookian
age. Accordingly, and in the absence of competent evidence of contrary sig-
nificance, the l)ase of the Mi.ssissippian in these States should be drawn at the
base of the CliMltaiKiogiin. Tliat tliis principle is properly api)licaiiie in this
case is intlicated by botli stratigraphic and fauna! evidence.

5. The strongest and most widely recognizable physical break between un-
doubted Devonian and equally well accredited Mississippian deposits In Ohio,
Indiami. Illinois, Iowa. Missouri, Ariv.insas. ni<l:ihonin, Kentucky, Tcnnes.see,
and Alabiini.i occurs at tiie li:ise of tiic CliattMnoogjin or KiM4l<'rhool<i;iii series.
Conunonly the base of this series is marked by a sandy conglomerate; and,

98 PROCEEDINGS OF THE PHILABELPHIA MEETING

except in certain limited areas wliere it is underlain by similar Devonian stiale,
the lithologic break is conspicuous. This break, moreover, marks a strong
transgression unconformity which brings the Chattanoogan in contact with
many widely differing older formations, ranging in age from Ordovician to
late Devonian. The recent tendency to limit the Mississippi in Ohio and
adjacent States at, or at an horizon supposedly corresponding to. the base of
the Bei-ea sandstone is regarded as impractical and generally impossible, ex-
cept in Ohio, and as inharmonious with long-established practice in the Mis-
sissippi Vallej' and in New York. This imperfectly considered effort would
subordinate a highly important and perhaps universally recognizable dias-
trophic boundary to one that is but locally definable and on the whole of
greatly inferior taxonomic significance.

(j. The Louisiana limestone in Missouri and the Chonopectus sandstone at
Burlington, Iowa, are underlain by gray or black shales which have been and
are yet commonly x'eferred to the basal j)art uf the Kinderhookian series.
These basal shales correspond in position with the Cleveland and Huron shales
of Ohio, and on this ground alone may be correlated with them.

7. In Missouri these basal shales contain fossils. None of the species are
of unquestionable Devonian types. On the other hand, a large proportion of
their number, especially of the invertebrates near the top, is identified with
otherwise t.vpioal Louisiana limestone species. The shale contains also re-
mains of fish which are closely allied to, and perhaps in part identifiable with.
Huron shale species. Fossils occur in these shales also at Burlington. Here
they have a more decidedly Mississippian aspect than pertains to the succeed-
ing Chonopectus fauna.

8. Remains of Arthrodirian fishes, especially Dinichthys, occur at different
horizons in the Chattanoogan series, the first being near the base, the last at
the very top. The last being unquestioned Mississipjiian. it follows that
Dinichthys, at least, is not confined to Devonian formations. Indeed, the evi-
dence in hand indicates that most of the genera of fishes found in Upper
Devonian rocks range upward into the Mississippian. None of the Chatta-
noogan fishes, however, are specifically identical with any of those found in
undoubted Devonian rocks.

r>. The evidence of the plants is much the same in tenor as that of the
fishes; but here it seems that at least one long-ranging (Genesee and Portage)
species passes without recognizable modification into the lower part of the
Chattanoogan. This apparent Devonian alliance, however, is offset by another
plant which unites these lower Chattanoogan beds with one at the extreme
top of the series, which all agree is of Mississippian age. Only a few plants
are as yet known from the Chattanoogan series. With the exception of the
first (Pseudohoniia inornata) and possibly another, all of the species are con-
fined to this series; or, if represented elsewhere by identical or closely allied
forms, these occur in beds that are either definitely known to be of post-
Devonian ages or in deposits about which geologists have differed as to whether
they should be called Devonian or MLssissippian.

10. Minute teeth and plates, known as conodonts, are rather generally dis-
tributed in the black shales of the Chattanoogan series and are doubtless the
most abundant of its fossils. American authors commonly have compared
these with the conodonts of the Genesee shale described by Hinde, forgetting

ABSTRACTS OF PAPERS 99

entirely that such teeth occur also in Carboniferous beds in England. Scotland.
Russia, and America. Granting that some of the Chattanoogan conodonts are
not readily distinguishable from the late Devonian species, it is nevertheless
true that on the whole these two microfaunas are far from identical. On the
contrary, it is chiefly among the Mississippian conodonts of Europe and Amer-
ica that the middle and lower Chattanoogan species find their closest allies.
11. Though the general aspect of some of the American faunas of early
Mississippian age, especially those in which the pelecypods and corals pre-
dominate, like the Conewangs ("Bradfordian") of New York and Pennsyl-
vania, the Bedford of Ohio, the Ridgetop of Tenne.ssee. the Chonopectus sand-
stone of Iowa, and the Chouteau of Missouri, is decidedly Devonian, the fact
that these Devonian reminders are holdovers, in every instance sufficiently
modified to be distinguished, must not be ignored. Except the strange types
which .subsequently invaded from other faunal realms, the Devonian faunas
which entered the North American continental basins from the Atlantic and
Gulf of Mexico are but earlier developmental fades of the Mississippian
faunas of the same basins. Naturally, then, the Devonian characteristics are
still obviously displayed in these near descendants. But it is the new things,
like Prodnctus, which have never been seen in standardized pre-Mississippian
formations, that tell the truth unmi.stakably. As such unquestioned Missis-
sippian types are found in the iMississippi Valley beneath, in, and between
each and every one of the pseudo-Devonian faunas mentioned, the a.ssignment
of the whole of the Kinderhookian beds in the Mississippi Valley seems fully
warranted. Granting this proposition, the case may be said to be established
no less firmly with respect to the Chattanoogan series by the physical and
faunal relations shown to exist l)etween the latter and the Kinderhookian.

Eead ill full from manuscript.

The section adjonrned ai 5 o'clock p. m.

TITLE.S AXn A15STKACTS OF PAPERS PRESENTED BEFOKK TIU: I'lrTRD SECTION

AND DISCUSSIONS TIT KR RON

The Third Section met at 2.40 o'clock p. in., with Vico-l'irsiilciii II. I'..
raltnii ill tho cliaii' ami E. O. Ilovey actiiifi" as secretary.

(liar, IS 01' Till': ii;<tN oh'Fft iv kiiwna. swF;nr::v

BY RECil.XALU A. DAI.Y

{Abst7-act)

Field data collected in the snninxM- of 1014 suggest that tho Kiruiia ores,
forming probably the largest higli-grade iron-oro bodies now being worked in
any country, arc difrerciitiatos ;';( situ from a m.ignia. most of which has solidi-
fied as fhe adjacent (luarfz jiorpliyry. Tliat kcratophx ric porphyry, like the
o|(](«i- syenite porphyry of the district, is believed to 1k' of intrusive origin. Tho
two iK)rphyries togetiier ai)pear to represent a fine example of a coinposito
(double) laccolith, injected info a (Iiir-k. chiefly volc-inlc series of ho<ldod rocks.

VIII — Bdll. Geol, Soc. Am., Vol,. J*i, 1014

100 PROCEEDINGS OF THE PHILADELPHIA MEETING

After the injection of the quartz porphyry the magnetite-apatite ores separated
out of its magma in small, nodular units. Many of these units settled to the
bottom of the quartz iwrphyry magma, forming the main ore bodies at the con-
tact with the somewhat older, underlying syenite porphyry. Many other units,
now angular as well as round, were frozen in at higher levels; these are the ore
inclusions of the Aisible quartz porphyry — bodies which some authors have
hitherto regarded as xenoliths, thereby obscuring the genetic problem.

Presented l)y title in the absence of the anthor.

ORIGIN OF THE ROCKY MOUNTAIN PHOSPHATE DEPOSITS
BY ELIOT BLACKWELDER

(Ah sir act)

The author presents this as a preliminary statement concerning the origin
of the Rocky Mountain phosphate deposits.

Among the world's known deposits of lime-phosphates at least six genetic
varieties have been clearly recognized:

Primary :

Pegraatitic (for example. Norway). Gumio (for example, Redonda Is-
land), Marine sediments (for example, Tunis).
Secondary or Metamorphic :

Surface residual concentrations (for example. Quercy). Phosphatized
limestone and other rocks (for example, Florida "hard phosphate"),
Detrital deposits (for example, Florida "river pebble").

The voluminous Permian (?) phosphate strata of Wyoming, Idaho, and ad-
jacent States are marine sediments analogous to dolomite and limestone.
Some points about their origin have already been establishec . Girty. Gale,
or other observers. These are considered, and to them are added other safe
inferences as to the conditions of origin. The Rocky Mountain phosphatic
beds apparently resemble those of Algeria-Tunis, Belgium, Wales, Sweden, and
Tennessee (Devonian only) ; but are unlike tho.se of Estremadura (Spain),
southern France. Norway, Florida, the Carolinas, and the Peruvian Islands.
They belong, therefore, to the third class above noted. The foreign deposits
most resembling those of the Rocky Mountains have been carefully studied,
and the best interpretations of them, appropriately modified, seem to apply
quite as well to oui- western beds. Dmltting arguments, the chief points in the
partial explanation thus far elaborated are the following : In the ocean special
conditions of currents, temperature, etcetera, not yet understood, may have
induced the wholesale killing of animals over a large area and accumulation
of the putrefying matter on the sea-floor in moderate and shallow depths.
Anerobic decomposition produced ammoniacal solutions which dissolved the
solid calcium pho.sphate present in bones, teeth, brachiopod shells, and tissues.
The putrefactive conditions also prevented the existence of sessile bottom
organisms, and most calcareous shells descending from the surface were prob-
ably dis.'^olved i\v the abundant carbonic acid arising from the decay. For
physico-chemical reasons, already partly understood, the pho.sphatic materials

ABSTRACTS OF PAPERS 101

were quickly redeposited in the form of liydrou.s calcium cai'bo-phosphates,
locally filling, incrusting. and replacing shells, teeth, bones, etcetera, but espe-
cially forming oolithoid granules of colophanite, and finally a phosphatic
cemont among all the particles. The granular texture is ascribt^d chiefly to
physico-chemical conditions like those which result in oolithoid greenalite,
limonite, aragonite, etcetera. After having been formed in quiet water, some
of the granules were reached by bottom-scouring currents and incorporated in
clastic deposits, and in some instances were even strewn over eroded rock
surfaces, and so became constituents of basal conglomerates.

One of the chief outstanding pi-oblems relating to the origin of the western
deposits is the nature of tlie environment capable of supplying the inferred
successive layers of animal carcasses. This calls for more exact paleogeo-
graphic data than are now available, although plausible suggestions may be
presented. Other problems lie in the domain of sea-bottom physics and chem-
istry and relate to the exact cycle of changes between dissolved apatite washed
in from the land and the final precipitation of colophanite on the sea-floor.

Presented by title in the absence of the author.

REGIONAL ALTERATION OF OIL SHALES
BY DAVID WHITE

(Abstract)

The examination of "oil rocks," such as cannels anil lichly l)ituminous
shales which yield petroleums on distillation, lying in or beneath coal-bearing
formations, shows that the organic matter of the shales, etcetera, is, in general,
regionally altered and carbonized together with the coals, the alteration of the
organic debris by the dynamic agencies being parallel in both. A study of the
distribution of petroleums and their salient features seems to show that: (1)
No commercial pools of oil are to be found in regions where the coals in or
above the oil-bearing formations have reached the stage of carbonization at
which the fixed carbon (proximate analysis) exceeds 75 per cent of the pure
coal, though gas pools diminishing in importance may lie l)oyond ; (2) in re-
gions of complete anthracitization the carbonaceous matter in the associated
shales is correspondingly fixed; (3) the oils of pools in regions of relatively
high fixed carbon in the rocks are, in general, highest in saturated hydrocar-
bons, and so highest in hydrogen and lowest in gravity; (4) in passing into
zones of successively lesser alteration of the organic debris the oils are of
lower rank and the unsaturated and lieavier hydrocarbons are, on the whole,
more and more in evidence, the lowest grades of oils being found in forma-
tions in which the solid fuels are lignitic in rank; (5) while the residues of
the organic debris are progressively altered, with the elimination of oxygen,
nitrogen, and hydrogen, with some carbon, to composites progressively richer
in carbon, the liquid distillates in the rocks as the alteration advances be-
come richer in hydrogen — that is, while the carbonaceous n>sidues in the rocks
])CCome more distinctly caiiioniz(>d their li(|uid liyrlrocaibon distillates iioconio
more fully hydrogenizod, the processes being in a way comiilcinentary.

Occurrences of abnormally high grade oil in low grade regions are probably

102 PROCEEDINGS OF THE PHILADELPHIA MEETING

due either to filtration or to migration from more altered rocks lielow. In
cases of igneous rock metamorpliism the effects may be erratic, distillates in
small quantities being occluded in the magma, which also may contain inclu-
sions of the mother rock. The limitation of commercial oil pools to regions of
not too advanced alteration of the buried carbonaceous deposits bears unfa-
vorably on the "inorganic" theoi'y of the origin of petroleum.

Presented 1)\' title in the alisence of the autlioi'.

OIL POOLS OF SOUTHERN OKLAHOMA ANU NORTHERN TEXAS

BY .JAMES H. GARDNER

{Abstract)

The Wheeler and Healdton oil pools In southern Oklahoma and the Petrolia
and Electra pools in northern Texas owe their origin to distinct folding of
strata within the influences of the Arlnickle and Wichita ^Mountains in south
ern Oklahoma. I'rominent structural features have been produced subsequent
to the deposition of the so-called Permian Red Beds which, near the uplifts,
lie unconformably on Pennsylvanian and lower beds. The main oil-bearing
sands lie in the Pennsylvanian with the exception of the Wheeler pool, which
bears oil from the basal member of the Red Beds. Structure contour maps of
the Wheeler and Healdton fields compare with Udden's map of the Petrolia
field and are typical of the main pools of northern Oklahoma and southern
Kansas. Underground stratigraphy from comparison of well logs shows per-
sistence of certain beds useful in the correlation of the oil sands in this newly
developed region which offers many possibilities of undeveloped production.

Read in full from luamiscripi liy Arthur M. ]\Iiller in the absence of
the author.

NATURAL GAS AT CLEVELAND, OHIO
BY FRA.XK R. V.\X HORN

(Abstract)

For many years gas has been found in the Upper Devonian Ohio shales at
depths of 600 to 800 feet. From 1905 to 1008 drilling M'as tried at depths of
2,600 to 2,800 feet in the region west of Cleveland, but with little success.
One well Is reported to have produced 250.000 cubic feet daily, but most of
them were left uncapped. Nothing more was done until about three years
ago, when several wells were drilled inside the city limits with considerable
success. Early in 1914 a boom developed, and now probably 600 wells have
been drilled or are partly finished. All reach about 2,700 feet to the Clinton
formation, which is never more than 14 feet thick. It Is very diflicult to ob-
tain any accurate records, but the reported volume ranges from 10 million
cubic feet in some to dry holes in others. Pressures range from 200 to 1,100
pounds per square inch. The writer knows of one well which came in March
with over four million cubic feet. In May it was producing but one million
cubic feet at a pressure of 350 pounds. Now it has dropped to 100,000 feet

ABSTRACTS OF PAPERS 103

dailj'. As yet there is no proof of any geological structure to cause tlie accu-
mulation, which seems to be in a very limited area. The close spacing of the
drill holes, which often does not exceed 100 feet, will probably result in a
rapid exhaustion of the supply.

Read in full from manuscript.

Remarks were made by Messrs. W. Lindgi-en and R. S. Woodward,
and reply by the author.

ORIGIN OF THICK SALT AND QYP8UM DEPOSITS
BY E. B. BRANSON

{Abstract)

The main difficulties in explaining the origin of thick salt and gypsum de-
posits which are not in association are: (1) in accounting for basins deep
enough to hold the necessary volume of water; (2) in explaining the rarity
of other salts in the deposits; (3) in accounting for the absence of salt de-
posits above the gypsum ; (4) in explaining the absence of sedimentary im-
purities, and (5) in accounting for the absence of fossils. These difficulties
are met by a modified bar hypothesis, which assumes that on the drying up
of large interior seas the waters became isolated into smaller basins, with
marginal basins overflowing on account of receiving the drainage formerly
coming into the larger seas, and that in the overflow concentrated waters were
brought to the innermost isolated basins, and evaporation from these caused
riipid deposition of salt or gypsum. The absence of interbedding of salt and
gypsum may be due to the gjpsum having been precipitated out before the
highly concentrated waters entered the innermost basins.

Read in full from manuscript.

Discussion

Prof. L. V. PiRssoN desired to point out that if he understood the purpose
of the paper, it seemed to him that the matter of the lateral circulation of
saline solutions of differing concentration and density had not been sufficiently
discussed. If there were a primary basin of concentration which brought the
sea-water to one-fifth the original volume, when fresh water from the drainage
basin came in on this it would, from its lower density, float on the heavier
solution and rise to the basin rim. An example of this is seen in the Amazon,
whose fresh water floats over the sea-water to a great distance out in the
ocean when the overflow from the first basin took place. If this is due to
seasonal precipitation, it would be liugely of fresh water carrying some of the
denser solution with it, especially toward the end of the overflow; or, in other
words, it is hard to see how the dense solution could be inovcil out oi' its Itasin
into the .second one without mixing :nul coiisciiiUMit dilution.

I'rofessor l'ir.s.son also pointed out that in a suitable arraiigfuient uf salt
lake, bar, and bay, where ev.iporation was greatest over the latter, it was
conceivable Hint tluTc miglit be .iii inward surface current into the bay. a
sinking of tlie concentrating saline w.itci-. ;nid an outward bottom current of

104 PROCEEDINGS OF THE PHILADELPHIA MEETING

the denser solution. When the concentration had reached a proper point, there
might then be precipitated on the bottom of the bay a single salt, such as
gypsum. This process might go on until all the gypsum of the lake was con-
centrated on the bottom of the bay.

Further remarks were made by Dr. H. M. Ami and the author.

CRYSTALLINE MARBLES OF ALABAMA ^
BY WM. F. PEOUTY

{Abstract)

The crystalline marbles of Alabama occur in a long, narrow, and rather
well defined valley, which extends through Talladega and into Coosa County,
H distance of about 35 miles. The width of the marble-bearing portion of the
valley varies from one-fourth to one and one-half miles. The dip of the
marble in this belt is hi an easterly direction and at about thirty degrees. To
the southeast of the marble occurs the Ocoee phyllite mass, from which the
marble is separated for most of the distance by a thrust fault of variable throw.
The strike of the marble is consequently often different from the trend of
the valley, and the age of the marble at different places varies from Cambrian
to Ordovician.

The present development is mainly in the central and southwestern portions,
where there is a greater thickness of the marble.

The marble is highly crystalline, medium to fine grained, with markedly
ijiterlocking crystals and unusual translucency. Beds of talcose schist con-
stitute the main impurity. A number of grades of marble are marketed, rang-
ing from statuary-white through cream-white and blue-toned to the varieties
showing considerable clouding or banding by the greenish-toned schist. The
marble is largely used for interior dec-oration and commands a high price.

The crustal movements in the field are well shown, locally, in the "slicks,"
drag-folds, and elongated crystals, and the field offers interesting opportunity
for the study of the relation of movements to unsoundness. The development
work shows the benefit of careful prospecting for lines of unsoundness and
directing operations to conform to the lines of structural weakness.

Presented l)y title in the absence of the author.
The section adjourned at 3.58 o'clock p. m.

ANNUAL DINNER

The annual dinner of the Society was held at the Hotel Walton, about
140 persons participating. E. 0. Hovey acted as toastmaster, and the
speakers of the evening were W. Liudgren, H. F. Osborn, C. D. "Walcott,
C. E. A^an Hise, W. W. Atwood, and F. R. Van Horn.

I By permission of the State Geologist of .\labama.

abstracts of papers 105

Session of Thursday, December 31

The Society convened at 9.37 o'clock a. m., with Vice-President H. B.
Patton in the chair.

After sundry announcements by the Secretary, the Society proceeded
to the consideration of scientific papers.

TITLES AND ABSTRACTS OF PAPERS PRESENTED IN GENERAL SESSION AND

DISCUSSIONS THEREON

PRESENT CONDITION OF THE VOLCANOES OF SOUTHERN ITALY

BY H. S. WASHINGTON AND A. L. DAY

(Alystract)

A brief description of the general condition and state of activity at Vesuvius,
Etna, Vuleano, and Stromholi, as observed during the summer of 1914,

Presented in full extemporaneously by the senior author.

RECENT ERUPTIONS OF LASSEN PEAK, CALIFORNIA
BY J. S. DILLEB

(Abstract)

Lassen Peali, in northeastern California, at the southern end of the Cascade
Range, has long been considered an extinct volcano, but has recently shown
signs of rejuvenescence. The first of the recent outbreaks occurred at 5 p. m..
May 30, 1914, and since then many eruptions have occurred. The nature of
this remarkable phenomenon was illustrated and discussed.

Eead in full from manuscript.

Remarks on the paper were made by Messrs. W. J. Miller, .7. S. Diller,
and H. B. Patton.

PHYSIOGRAPHIC STUDY OP THE CRETACEOUS-EOCENE PERIOD IN THE
ROCKY MOUNTAIN FRONT AND GREAT PLAINS PROVINCES

BY GEOBGE H. ASHLEY

(Abstract)

The study of the rocks, especially of the cfoal beds, the structure and the
life in the provinces iianiod. :ip|»e:irs to indicate that IJpiter Crelafeous time
in that region was oi-cupied liy a single movement of sult.sidence, somewhat
irregular, but on the whole persistent ; that this was followed by a period
of general and differential uplift, to be followed in turn by renewed subsidence,
interrupted locally from time to time by i)ronounced movements of differential
uplift. Comparison is made between this interpretation and the assumed con-

106 PROCEEDINGS OF THE PHILADELPHIA MEETING

clitions in the eastern United States and certain deductions drawn as to the
point in the time scale at wliich the first general uplift occurred.

Presented in abstract extemporaneously,

RELATION OF PHYSIOGRAPHIC (JHAXGES TO ORE ALTERATIONS

BY WAU^CE W. ATWOOD

(Abstract)

While a land-mass is being dissected, the ground water table is slowly
lowered through that mass until, at the peneplain and baselevel stages, the
ground water table remains almost stationary for long periods of time. During
successive cycles of erosion the position of the baselevel of erosion in the land-
mass being dissected must change, and, if climatic conditions remain constant,
such changes are necessarily accompanied by changes in the position of the
ground water table. If the land-mass is elevated, the baselevel will be lowered
through the land, and the ground water table will be slowly lowered. When
it land-mass is depressed the baselevel of erosion and the ground water table
are elevated throughout that land-mass. Moist climates will raise the ground
\Aater table and dry periods lower that table. As the ground water table is
raised or lowered, the zones in which the chemical changes associated with
the secondary alteration of ore deposits take place are varied in thickness.

These facts indicate that physiographic studies may be profitably applied
in the study of ore alterations, and conversely that the record of ore altera-
tions may furnish important data bearing on the physiographic evolution of
the districts concerned.

The study of secondary ores by various investigators has called for in-
tensive physiographic studies. During the past season field-work was done in
the vicinity of Butte, Montana, and Bingham Canyon, Utah, to determine the
relationship of physiographic evolution to the secondary enrichment of ores
in those regions. In this paper the problem of the application of physiography
to the investigation of secondary ores was defined and some of the results of
the past season's field-work were presented.

Presented in abstract extemporaneously.

GRAPHIC PROJECTION OF PLEISTOCENE CLIMATIC OSCILLATIONS

BY CHESTER A. REEDS

(Abstract)

Penck's curve, as presented on page 1168 of "Die Alpen im Eiszeitalter"
(1909), expresses graphically the climatic oscillations of the alpine district for
Pleistocene and post-Pleistocene time. Tlie key to the four glaciations and
the three interglacial stages indicated in the curve was found in the four out-
wash deposits of glacio-fluvial streams on the northern foreland of the Alps
in the vicinity of Ulm and Munich. Along tlie present stream valleys the
glacio-fluvial deposits are arranged in terraces, the oldest occupying the high-
est position and the youngest the lowest level. When the key was carried in

ABSTRACTS OF PAPERS 107

mind to the French and Italian Alps, the remarkable association of these de-
posits on the northern foreland was found to be applicable throughout. Hence
the names of four small tributaries of the Danube which cross the outwash
deposits on the Bavarian plateau — Giinz, Mindel, Riss, and Wiirm— ^were ap-
plied by Penck and Briickner to the 1st, Ilnd, Ilird, and IVth glaciations.
The deposits of the Tlird or Riss glaciation in the Swiss and French Jura
extend farther out on the foreland than the deposits of the other glacial ad-
vances, but in other districts the morainal deposits of the Ilnd or Mindel
stage extend beyond that of any other ; hence it is regarded as the most exten-
sive of the four alpine glaciations. The morainal and outwash deposits of the
1st or Giinz glaciation are least in evidence, while tliose of the IVth or Wiirm
glaciation, the last, are most in evidence.

Tliat the temperature of the alpine region was considerably colder during
the stages of glaciation than during the interglacial stages and the Present,
wliich is at the close of the retreating liemicycle of the last glaciation, is shown
conclusively by the depressed snow-lines. Penck has determined their posi-
tion in the Alps for all four glaciations. They have a distribution parallel to
that of the present snow-line, but occupying lower levels, namely, Giinz, 1,200
meters ; Mindel. 1,350 meters ; Riss, 1,300 meters, and Wiirm 1,200 meters be-
low the present snow-line. During the interglacial stages the snow-line was
approximately 300 meters higher than the present one. From the Hettinger
breccia, near Innsbruck. Penck determined that there was a temperature
variation of 1° C. for every 200-metei- change in the altitude of the snow-line.

The unit of measurement which Penck used in estimating the duration of
the Pleistocene period is tlie retreating hemicycle of glaciation of the IVth or
Wiirm stage, better known as the post-Glacial period. In the alpine district
Penck and Briickner found that in this retreating hemicycle there were three
minor advances, called the Biihl, Gschnitz, and Daun stadia. These advances
were preceded by a prominent minor retreat — the Achen oscillation. From the
lignite deposits of Diirnten, the deposits of the Muota deltas, and the turf de-
posits in many of the glacial swamps it has been possible to estimate the
duration of this hemicycle of glaciation in years, as follows :

Suhdivisions of post-Glacial Time

Years

Achen oscillation 9,000

Biihl advance and retreat 5,000

Gschnitz advance and retreat 4,000

Daun advance and retreat 3.000

Age of Copper 1,000

Post-Copper time 3,000

Total 25.000

The csthiiatt" mi tlic duration of post-(iUu-ial tiiiu- in .Vniciica is l)ast'd chielly
on the recession of tlic waterfalls of Niagara and Saint .\iitlioM.\. Recently
(Coleman' made an csliniate liased on the rate of wave erosion on the shores of
Lake Ontario and glacial Lake Iio(|iiois. Twenty-tive thous.md years is a tig-

' A. V. C'oleuiun : I'roceedinga Twelfth Interu. Geol. Cong., Canada, liil,!.

108

PROCEEDINGS OF THE PHILADELPHIA MEETING

ure which falls within the estimates made by Coleman, Taylor, Lyell, Cham-
berlin, and Salisbury. It is a bit under those of Fairchild, Sardeson, and
Spencer and above those of Gilbert and Upham. It is considered a conserva-
tive figure.

Estimated Duration of Pleistocene Oscillations

Post-Glacial

25,000

20,000

IVth Glacial

25, 000

50,000

20,000

40,000

3rd Interglacial

100,000

1.50,000

60,000

100,000

Ilird Glacial

25,000

175,000

20,000

120,000

2nd Interglacial

200,000

375,000

240,000

360,000

Ilnd Glacial

25,000

400,000

20,000

380,000

1st Interglacial

75,000

475, 000

100, 000

480,000

1st Glacial

25, 000

500, 000

1
1

20,000

500,000

Pre-transitional

25,000

525, 000

20,000

520,000

Units

Years

Totals

Units

Years

Totals

eeds

1914

^enck

19(19

Penck states that it must have been 16,000 to 24.()(X) years from the Buhl
stadium to the present, with 20,000 years as an average, and 25,000 to 40,000
years from the beginning of the Achen retreat to the present. In selecting a
figure, however, which shall be used as a unit of measurement in calculating
the duration of the entire Pleistocene period, he chooses 20,000 years as the
length of post-Wiirm time.

The correlation of the mountain glaciations of the Alps with those of the
Scandinavian continental ice-fields of Pleistocene time has not been worked
out in all regions, but there is sufficient information at hand to saj- that there
were four advances of the continental ice over northern Europe which corre-
spond to tlie periods of ice-advance on the alpine forelands. Geikie remapped
in 1914 the llnd, Ilird, and IVth glaciation distribution in Europe. G. de
Geer delimited the retreating stages of the IVth glaciation in tlie Scandinavian
peninsula in 1912. »

A correlation of American with European glacial deposits has been made by
Leverett. By considering with Leverett- the so-called lowan glaciation con-
temporaneous with the Illinoisan, it is possible to correlate the Giinz glaciation

2 F. Leverett : Zeitsehrift fur Gletcherkunde, vol. iv, 1910, pp. 282-283.

ABSTRACTS OF PAPTSRS 109

with the Nebraskan, the Kausan with the Mindel, the Illinoisan with the Riss,
and the Wisconsin, early and late, with the Wiirm. There are corresponding
interglacial stages. With the time units of Cliamberlin and Salisl)ury' —
2, 4, 8, 16 — in mind for the duration of the last three glaciations, based on the
degree of weathering of American glacial deposits, it is possible to construct
a curve similar to Penck's, but differing in length and the number of units
assigned to the interglacial stages. In tabular form the data appear as on
page 108.

Presented in abstract from notes.

GEOLOGIC DEPOSITS IN RELATION TO PLEISTOCENE MAN
BY CHESTEK A. KEEUS

(Ahstract)

The iiresent known distril)ution of Pleistocene man through southern Eu-
rope, tlie Mediterranean boi-der, and Java points to the conclusion that this
early man lived along river courses, on the adj.icent uplands, in caves and
grottoes which overlooked well defined river valleys, and on the seashore.
Human remains have been found entombed in a few caves within the region
of mountain glaciation — for example, Freudenthal, Kesslerloch, and Schwei-
zersbild, in Switzerland — but most of the finds have been made in the southern
non-glaciated portions of Europe. The vicissitudes and the ameliorations of
climate during the glacial and interglacial stages no doubt caused southward
or northward migrations of peoples or encoui'aged congestion in the limestone
caverns of Belgium, France, Germany, and northern Spain. With the re-
peated formation of continental ice-slieets on the Scandinavian plateau during
periods of glaciation and their movement outward in all directions across the
adjacent basins and lowlands of northern Europe, together with the appenr-
ance of ice-caps on the high mountains of southern Europe, the lowering of
the snow-line on the mountain slopes, the development of snow-caps on pla-
teaus of but moderate relief, the extension of the glaciers into aprons and
tongues on the piedmont areas, and the choking of the river valleys with ice
and deposits, glacial man must have felt that snow and ice wore the governing
forces. The warmer interglacial epochs were more to his liking. In the pres-
ent terrace and loess deposits along the river courses and in the cave and
grotto fillings eight human culture stages have been delimited within recent
years. They have been called, beginning at the bottom, pre-Chellean. Chellean,
Acheulean, and Mousterian as Lower Paleolithic, and Aurignacian, Solutrean,
Magdalenian, and Azylian-Tardenoisan as Upper Paleolithic. In the cavern
and grotto deposits of tlie Dordogne, southern France, most <>f the culture
stages appear in regular geologic sequence one above tlie other. Human re-
mains and culture stati<ms of Glacial, inter-Glacial, or post-Glacial age have
been riMiinl in sipiirnxiiuately tliice hundred dilft'rent localities.

Presented in abstract fiom notes.

aChamberlln and Salisbury : Text Book of Geology, vol. 111. lyotJ, p. 414.

110 PROCEEDINGS OP THE PHILADELPHIA MEETING

PHYSIOORAPHIC FEATURES OF WESTERN EUROPE AS A FACTOR IN THE WAR

SY DOUGLAS W. JOHNSON

(Abstract)

Every military caiupaigu is controlled to some extent by the surface features
of the country over which the contending armies must move. The physiography
of a region may therefore profoundly affect both the detailed movements of
armies and the general plans of campaign. An examination of the phys-
iographic features of western Europe in the light of recent events enables one
to comprehend more fully the strategic importance of many places mentioned
in war dispatches and throws valuable light upon the question as to why the
neutrality of Belgium was violated.

Presented in abstract extemporaneously.

VOTE OF THANKS

The following- vote of thanks was passed :

The Geological Society of America desires to express its most cordial
thanks to the Academy of Natural Sciences of Philadel])hia for hospitality
extended to the Society on the occasion of its twenty-seventh annual
meeting.

The Society desires further to express to its local committee its high
appreciation of the indefatigable labors which have resulted in one of
the most successful meetings in the Society's history and for the generous
liospitality manifested by the provision of daily luncheons and the gen-
eral smoker of Tuesday evening.

JOHN BOYD THACHER PARK: THE HELDERBERO ESCARPMENT AS A

GEOLOaiCAL PARK

BY GEOEGE F. KUNZ

(Al)Stract)

A most important benefaction to the State of New York is the beautiful
John Boyd Thaeher Park, opened with appropriate ceremonies September 14,
1914. During the winter of 1913-1914 the American Scenic and Historic Pres-
ervation Society cooperated with Mrs. Emma Treadwell Thaeher, widow of
John Boyd Thaeher. to realize her generous purpose of donating to the State
a superb trust of 350 acres of land for a public park, as a memorial of her
husband, and in March, 1914, a bill was introduced and passed in the legis-
lature accepting the gift and constituting the American Scenic and Historic
Preservation Society the custodian. The park embraces the most picturesque
and geologically interesting part of the Helderberg range in Albany County.

The remarkable geologic formations to be seen in this park include one of
the finest exposures of the Upper Silurian and Devonian strata in the country
and offer classic types of several formations, as is shown by the designations

ABSTRACTS OF PAPERS 111

"Helderberg limestone" and "Helderberg group" ; the rocks contain a great
number of characteristic fossils, especially of marine forms. On the slope
appear Hudson shales, and flaggy sandstones of the Hamilton formation crown
Countryman Hill. The deep amphitheater at Indian Ladder lias been worn
out by the water of a small stream.

There is now a small museum and library in the park, and the Geological
Survey has set up a bench-mark. It is hoped that very soon the cottage
building for the reception of guests will be completed, so as to afford com-
fortable shelter for visiting geologists who wish to study this Mecca of geolo-
gists. The library would be glad to receive geological publications linving any
{tearing on the local conditions ; such mail should be addressed to the Curator
of John Boyd Thacher Park, East Berne, New York.

Presented by title in the absence of the author.

The next paper was oii address made by Mr. Diller as retiring Vice-
President of Section E of the American Association for the Advancement
of Science, under the title

RELIEF OF OUR PACIFIC COAST
BY J. S. DILLER

(Ahstract)

The continental feature bordering the Pacific coast of the United States is
a mountain lielt of surpassing grandeur and composed in general of two lines
or ranges of mountain elevations with a depression between. For the most
part the two lines of mountains appear to be parallel with each other and the
coast, the Sierra Nevada and the Cascade ranges on the east and the Coast
ranges, including the Klamath Mountains of California and Oregon and the
Olympic Mountains of Washington, on the west, from the Mexican line to that
of British Columbia. Cross-folds connect the side ranges and separate the
great valley of California from the Willamette Valley of Oregon.

The Sierra Nevada is composed of folded sediments and igneous rocks of
various ages, from Silurian to .Jurassic, and faulted and tilted as one great
block, with long gentle slope to the west and steep slope to the east.

The Cascade Range is essentially volcanic and due mainly to volcanic up-
Iiuilding, though partly to uplifting, from Mount Adams, in Washington, to
liassen Peak, in Califoi'nia ; but beyond these limits the older crystalline rocks
ri.se to the surface.

The Klamath Mountains are in large measure like the Sierra Nevada in
their rocks, although more fossillferous, but differ in structure, being char-
acterized by broadly curved thrust-faults with the overthrust into (he i-oncave
curve and thus toward the Pacific Ocean.

The Coast Ranges of California and Oregon are composed almost wholly of
Me.sozoic and Tertiary rocks. In California the Coast Range rocks arc greatly
crushed and fauKod. hut in Oregon the coinprcssion has liooii nim-li less
intense.

The scclinii MiljdiiiiKMl ill 1 o'clock j). m.

112 PROCEEDINGS OF THE PHILADELPHIA MEETING

TITLES AND ABSTPtACTS OF PAPERS PRESENTED BEFORE THE SECOND SECTION

On Thursday nioruing the Second Section continued the reading of
papers, meeting in conjunction with the Paleontological Society, as
follows :

DEVONIAN OF CENTRAL MISSOURI
BY E. B. BRANSON AND n. K. GREGER

(Abstract)

The Devonian of central Missouri consists of five thin formations. The
lowest of these, which occurs in the eastern part of central Missouri, contains
a fauna closely related to that of the Jeffersonville limestone of Indiana. In the
western part of the area a thin formation of about the same age contains no
species in common with the eastern formation, but bears a fauna closely re-
lated to that of the Otis beds of Iowa. The Callaway limestone lies uncon-
formably on botli formations and is followed in the western part of the area
by the Craghead Creek shale, and both formations bear faunas similar to those
of the Upper Devonian of Iowa. In northeastern Missouri the formation
bearing the Jeffersonville fauna is succeeded by a thin black shale, the main
fauna of which consists of lingulas and dinichthyids.

Presented in abstract extemporaneously by the senior author.
Discussed by Messrs. Schuchert and Savage, with replies by Professor
Branson.

On account of their connection with the black shale problem, Professor
Orabau was requested at this point to give two papers listed under the
Paleontological Society's program.

OLENTANGY SHALE OF CENTRAL OHIO AND ITS STRATIGRAPHW

SIGNIFICANCE

BY AMADEUS W. GRABAU

(Abstract)

In its typical localities the Olentangy shale is intimately associated with
the Huron shale, this latter representing merely a change in facies. without
interruption of stratigraphic continuity. The Olentangy clearly belongs to the
Upper Devonic. resting disconformably on limestones of Lower Hamilton age.
I'he shales and limestones classed as Olentangy in northern Ohio are, how-
ever, early Hamilton, and considerably older than the Olentangy. This name
should therefore not be used for strata of Hamilton age, but instead the name
Trout series is proposed for the northern Ohio deposits of Hamilton age.

Presented in abstract extemporaneously.

ABSTRACTS OF PAPERS 113

HAMILTON aUOUP OF WESTERN NEW YORK
BY AMADEUS W. GRABAU

(Abstract)

The various subdivisions originally made by the author for the Hamilton
of Eighteen Mile Creek have been correlated with a similar number of sub-
divisions in central New York by the New York Survey. The validity of this
correlation will be considered and the facts suggesting that an error has been
made will be given. A new series of names for these subdivisions will be
prepared. A brief comparison with the Traverse group of Michigan will be
made.

Presented in abstract extemporaneously.

Discussion

A general and extended discnssion of the black sliale prol)lem then
followed, which was participated in by IMessrs. David White, Edward M.
Kindle, I. C. White, Charles S. Prosser, A. W. Grabau, E. 0. Ulrich,
H. P. Gushing, M. Y. Williams, and A. F. Foerste.

EXTENSION OF MORRISON FORMATION INTO NEW MEXICO

BY N. H. DARTON

(Abstract)

During the past few years the author has examined nearly the entire out-
crop zone of the Red Beds and their contact with overlying rock,s. It has
been found that in the northern half of the State the Red Beds are overlain
by deposits having all the characteristics of the Morrison formation in Colo-
rado, and in part of the area the outcrop is continuous from one State into
the other.

Presented by title in the absence of the author.

GEOLOGICAL RECONNAISSANCE OF PORTO RICO
BY CHARLES P. BERKEY

(Abstract)

This pai)er was l)asod on work of exploration continued for a month during
the season of 1914 under the joint support of the New York Academy of
Sciences and the insular government of Porto Rico. The primary purpose of
the reconnaissance was to determine the character and structural relations of
the princijial geologic formations of the island and to carry forward investi-
gations far enough to indicate some of the problems that should be made the
objects of special study in work which is to follow. Systematic observations
were made on two lines entirely acro.ss the island in sufficient detail to furnish
data for general geologic cross sections. These sections b.ive been drawn and
illustrate the fundamental structure of the island, as well as the geologic
basis of Its relief.

114 PROCEEDINGS OF THE PHILADELPHIA MEETING

There are two fiiiidanientally different series of formations separated by an
uiiconforniity. The older series is a complex of tuffs, shales, conglomerates,
;ni(l limestones, cut in a complex way by very numerous and occasionally very
large intrusive masses, chiefly of dioritic composition. In many parts of the
Lslaud these beds show complicated structural relations and much disturbance.
The younger series is of Tertiary age and is essentially a succession of marls
and limestone reefs and shale beds of considerable variety, but not affected
at all by igneous activity or very complicated dynamic disturbances.

Peculiar erosional effects are produced in certain districts where this latter
formation is the imderlying rock, and in some districts the inner margin of
the limestone belt, which is usually a narrow strip along the coast, develops
into a pronounced cuesta form. The unconformity between the two great
series is represented by an obscurely marked peneplain, which bevels across
all of the complicated structures of the older series ; but, except in the im-
mediate vicinity of the limestone margin, there is scarcely a trace of this plain
to be seen, because of the maturity of dissection.

A large number of photographs were taken to represent the characteristic
features, and a collection of typical rocks and fossils was made which are now
l)eing studied.

Presented in abstract extempnraneousl3\

Discussed by Messrs. Cbarles Schucbert and Gilbert van Ingen.

RELATION OF CRETACEOUS FORMATIONS TO THE ROCKY MOUNTAINS IN

COLORADO AND NEW MEXICO

BY WILLIS T. LEE

(Abstract)

The paper presented evidence that the unconformity in the Rocky Mountain
region, known as the post-La ramie. post-Vermejo, or post-Cretaceous, according
to locality, is of such magnitude and extent as appropriately to constitute the
Cretaceous-Tertiary boundary for this region. In opposition to the view that
highlands or large "islands" persisted in the Rocky Mountain region through-
out Cretaceous time, the facts now available indicate that the Dakota sand-
stone was laid down on a baseleveled surface, and that it originally extended
continuously over the present mountainous area of Colorado and New Mexico ;
also that the succeeding beds of Upper Cretaceous age covered this area.
Whatever surface warpings may have occurred during Cretaceous time, there
seems to have been formed in the Rocky Mountain region no barrier that
seriously interfered with the free distribution of the sediments in the interior
Cretaceous sea. When the post-Laramie uplift occurred these sediments must
have been removed before the pre-Cretaceous rocks could furnish the pebbles
found in the basal conglomerate of the post-Laramie formations. If the Cre-
taceous sedimentaries extended over the mountains with anything like the
thicknesses found on either side and also within the mountains, the uplift
necessai'y to obtain these pebbles indicates an orogenic movement of such
magnitude as to denote the close of the long period of Cretaceous quiescence
and to inaugurate the tumultuous period of orogenic disturbances of the
Tertiary.

Presented in abstract extemporaneously.

115

POUT-ORDOriCIAN DEFORMATION IN THE SAINT LAWRENCE VALLEY, NEW

YORK

BY GEORGE H. CHADWICK

{Abstract)

On the Canton quadrangle the Cambrian and Ordovician strata are notably
undulatory, the low anticlines trending with the Saint Lawrence Valley.
These Paleozoic structures bear some evident relations to the belts of pre-
Cambrian rocks underlying. The more intense disturbances represent pinch-
ings within pre-Cambrian valleys cut along Grenville limestone belts.

Presented by title in the absence of the author.
Adjourned at 12.30 o'clock p. m.

KeGISTER of THE PHILADELPHIA MEETING, 1911.

FELLOW 8

William C. Alden
Henry M. Ami
George H. Ashley
Wallace W. Atwood
Joseph Barrell
Florence Bascom
R. S. Bassler
W. S. Bayley
Charles P. Berkey
Edward W. Berry
E. B. Branson
Amos P. Brown
Barnum Brown
B. S. Butler
Stephen R. Capps
William B. Clark
John M. Clarke
H. F. Cleland
A. J. Collier
Alja R. Crook
Whitman Cross
E. R. Cummings
Henry P. Cushing
N. H. Darton

IX — Bull. Gkol. Soc. Am., Vol. 2R. 1914

Charles A. Davis
Edward V. d'Invilliers
J. S. Diller
C. R. Eastman
Herman L. Fairchild
Clarence N. Fenner
August P. Foerste
C. E. Gordon
Charles H. Gordon
Amadeus W. Grabau
Walter Granger
Herbert E. Gregory
George P. Grimsley
Baird Halberstadt
Chris A. Hartnagel
C. W. Hayes
Richard R. Hice
Arthur Hollick
Ernest Howe
E. 0. Hovey
l. hussakof
Douglas W. Johnson
George F. T\ay
J. F. Kkmp

116

PROCEEDINGS OF THE PHILADELPHIA MEETING

E. M. Kindle
Cyril W. Knight
S. H. Knight
Adolph Knopf

F. H. Knowlton
Henry B. Kummel
Willis T. Lee

J. VoLNEY Lewis
KicHARD S. Lull
S. AY. McCallie
George C. Martin
W. C. Mendenhall
George P. Merrill
Arthur M. Miller
Benjamin L. Miller
W. G. Miller
William J. Miller
Fred H. Moffit
Ida H, Ogilvie
Henry F. Osborn
Sidney Paige
Horace B. Patton
E. A. F. Penrose, Jr.
George H. Perkins
Louis Y. Pirsson
Joseph E. Pogue
Joseph H. Pratt
Charles S. Prosser
A. H, Purdue
Percy E. Eaymond
Harry Fielding Eeid
William N. Eice
John L. Eich
Heinrich Eies

T. E. Savage
F. C. Schrader
Charles Schuchert
E. H. Sellards
William J. Sinclair
Joseph T. Singewald, Jr.
Burnett Smith
George Otis Smith
Philip S. Smith
C. H. Smyth, Jr.
J. Stanley-Brown
Timothy W. Stanton
Lloyd W. Stephenson
Ralph W. Stone
George W. Stose
Charles K. Swartz
MiGNON Talbot
Frank B. Taylor
m. w. twitchell
Joseph B. Umpleby
Frank E. Van Horn
Gilbert Van Ingen
Thomas W. Vaughan
C. D. Walcott
Henry S. Washington
Thomas L. Watson
Walter Harvey AVeed
Carroll H. AVegemann
Lewis G. AVestgate

G. E. WiELAND

A. W. G. Wilson
John E. Wolff
David White
I. C. White

FELLOW-ELECT

E. J. Holden

In addition to the foregoing, there were registered at the meeting 7
members of the Paleontological Society, fi members of the American
Association for the Advancement of Science, and 63 visitors, including
wives of members and specially invited assistants and students.

OFFICERS, COREESPOXDENTS, AND FELLOWS OF THE
GEOLOGICAL SOCIETY OF AMERICA

OFFICERS FOR 1915

President :
Arthur P. Coleman, Toronto, Canada

Vice-Presidents :

L, V. PiRSSON, New Haven, Conn.
H. P. CusHiNG, Cleveland, Ohio
Edward 0. Ulrich, ^Yashington, D. C.

Secretary:

Edmund Otis Hovet, American Musenni of Natural History, New

York, N. Y.

Treasurer:
Wm. Bullock Clark. Johns Hopkins University, Baltimore, Md.

Editor:
J, Stanley-Bkown, 26 Exchange Place, New York, N. Y.

Librarian:
F. R. Van Horn, Cleveland, Ohio

Councilors:

(Tei-m expires 1915)

Whitman Cross. Washington, D. C.
WiLLET G. Miller, Toronto, Canada

(Term expires 1916)

R. A. F. Penrose. Jr., Philadelphia, Pa.
"W. W. Atwood, Cambridge, Mass.

(Term expires 1917)

Charles K. Letth. Madison, Wis.
Thomas T;. Watson. Charlottesville, Va.

(117)

118 TROCEEDINGS OF THE PHILADELPHIA MEETING

MEMBERSHIP, Wl-'i
CORRESPONDENTS

Charles Barrois, Lille, France. December, 1909.

W. C. Brogger, Christiania, Norway. December, 1900.

Giovanni Capeixini, Bologna, Italy. December, 1910.

Baron Gerhard De Geer, Stockholm, Sweden. December, 1910.

Sir Archibald Geikie, Hasslemere, England. December, 1909.

Albert Heim, Ziirich, Switzerland. December, 1909.

Emanuel Kayser, Marburg, Germany. December, 1909.

W. KiLiAN. Grenoble, France. December, 1912.

J. J. H. Teall, London, England. December, 1912.

Emil Tietze, Vienna, Austria. December, 1910.

FELLOWS
♦Indicates Original Fellow (see article III of Constitution)

Cleveland Abbe, Jr., U. S. Weather Bureau, Washington, D. C. August. 1899.

Frank Dawson Adams, McGill University, Montreal, Canada. Dec, 1889.

George I. Adams, Pei Yang University, Tientsin, China. December, 1902.

Josfi Guadalupe Aguilera, Instituto Geologico, Mexico, Mexico. Aug., 1890.

William Clinton Alden, U. S. Geological Survey, Washington, D. C. De-
cember, 1909.

Truman H. Aldrich, Birmingham, Ala. May, 1889.

John A. Allan, University of Alberta, Strathcona, Canada. December, 1914.

R. C. AiXEN, State Geologist, Lansing, Mich. December, 1911.

Henry M. Ami, Geological and Natural History Survey of Canada, Ottawa.
Canada. December, 1889.

Frank M. Anderson, State Mining Bureau, 2604 ^Etna St., Berkeley, Cal.
June, 1902.

Robert Van Vleck Anderson, 71 Richmond Terrace. Whitehall, S. W., Ix)u-
don, England. December, 1911.

Ralph Arnold. 92.'> Union Oil Building, Los Angeles, Cal. December, 1904.

(iEORGE Hall Ashley, U. S. Geological Survey, Washington, D. C. Aug., 1895.

Waixace Walter Atwood, Harvard University, Cambridge, Mass. Dec.. 1909.

RuFus Mather Bagg, Jr.. Lawrence College, Appleton, Wis. December. 1896.

Harry Foster Bain, 420 Market St., San Francisco, Cal. December, 1895.

Manley Benson Baker, School of Mining, Kingston, Ontario. Dec, 1911.

S. Prentiss Baldwin, 2930 Prospect Ave., Cleveland, Ohio. August. 189r;.

Sydney H. Ball. 71 Broadway, New York City. December, 1905.

Joseph A. Bancroft, McGill University, Montreal, Canada. December, 1914.

Erwin Hinckley Barbour, University of Nebraska, Lincoln, Neb. Dec, 1896.

Joseph Barrell, Yale University, New Haven, Conn. December. 1902.

George H. Barton, Boston Society of Natural History, Boston, Mass. Au-
gust, 1890.

Florence Bascom, Bryn Mawr College, Bryn Mawr, Pa. August, J 894.

Ray Smith Bassler, U. S. National Museum, Washington, D. C. Dec. 1906.

Edson Sitnderland Bastin, U. S. Geological Survey, Washington, D. C. De-
cember, 1909.

LIST OF MEMBERS 119

William S. Bayley, University of Illinois, Urbana, 111. December, 1888.
* George F. Becker, U. S. Geological Survey, Washington, D. C.

Joshua W. Beede, Indiana University, Bloomington, Ind. December, 1902.

Robert Bell, Geological Survey, Department of Mines, Ottawa, Canada. May.
1889.

Charles P. Berkey, Columbia University, New York, N. Y. August, 1901.

Edward Wilber Berry, Johns Hopkins University, Baltimore, Md. Dec, 1909.

Samuel Walker Beyer, Iowa Agricultural College, Ames, Iowa. Dec, 189G.

Arthur B. Bibbins, Goucher College, Baltimore, Md. December, 1903.

Eliot Blackwelder, University of Wisconsin, Madison, Wis. Dec, 1908.

John M. Boutwell, 1323 De la Vine St., Santa Barbara, Cal. Dec, 1905.

John Adams Bownocker, Ohio State University, Columbus, Ohio. Dec, 1904.
*John C. Branner, Leland Stanford, Jr., University, Stanford University, Cal.

Edwin Bayer Branson, University of Missouri, Columbia, Mo. Dec, 1911.

Albert Perry Brigham, Colgate University, Hamilton, N. Y. December, 1893.

Reginald W. Brock, University of British Columbia, Vancouver, B. C. De-
cember, 1904.

Alfred Hulse Brooks, U. S. Geological Survey, Washington, D. C. Aug., 1899.

Amos P. Brown, University of Pennsylvania, Philadelphia, Pa. Dec, 1905.

Barnum Brown, American Museum of Natural History, New York, N. Y. De-
cember, 1910.

Charles Wilson Brown, Brown University, Providence, R. I. Dec, 1908.

Henry Andrew Buehler, Rolla, Mo. December, 1909.

Bert S. Butler, U. S. Geological Survey, Washington, D. C. December, 1912.

G. Montague Butler, School of Mines, Corvallis, Oregon. December, 1911.

Charles Butts, U. S. Geological Survey, Washington, D. C. December, 1912.

De Lorme Donaldson Cairnes, Geological Survey Branch, Department of
Mines, Ottawa, Canada. December, 1912.

Fred Harvey Hall Calhoun. Clemson College, S. C. December, 1909.

Frank C. Calkin, U. S. Geological Survey, Washington, D. C. Dec, 1914.

Henry Donald Campbell, Washington and Lee University, Lexington, Va.
May, 1889.

Marius R. Campbell, U. S. Geological Survey, Washington, D. C. Aug., 1892.

Charles Camsell, Geological Survey of Canada, Ottawa, Canada. Decem-
ber, 1914.

Stephen Reid Capps, Jr., U. S. Geological Survey, Washington, D. C. Dec,
191L

Frank Carney, Granville, Ohio. December, 1908.

Ermine C. Case, University of Michigan, Ann Arbor, Mich. December. 1901.

George Halcott Chadwick, University of Rochester, Rochester, N. Y. De-
cember, 1911.

RoLLiN T. Ciiamberlin, University of Chicago, Chic-ngo, 111. December, 1913.

*T. C. Chamberlin, University of ('hicago, Chicago, IH.

Clarence Raymond Claghorn, Tacoma, Wash. August, 1891.

Charles H. Clapp, University of Arizona, Tucson. Arizona. Deivinber, 1914.
Frederick G. Clapp, 502 Fit/.simons BIdg., Pittsburgh, I'a. December. 1905.

*Wa.LiAM Bulujck Ciark, Johns Hopkins University. Baltimore. Md.

John Mason Clarke. Albany. N. Y. December. 1897.

Herdman F. Cleland. Williams College, Wlillamstown, Mass. Dec. 1905.

120 PROCEEDINGS OF THE PHILADELPHIA MEETING

J. MoBGAN Clements, 20 Broad St., New York City. December, 1894.

Collier Cobb. University of Nortli Carolina. Chapel Hill. N. C. Dec, 1894.

Arthur P. Coleman, Toronto University, Toronto, Canada. December, 1890.

George L. Collie. Beloit College, Beloit, Wis. December, 1897.

Arthur J. Collier, U. S. Geological Survey, Washington, D. C. June, 1902.
*Theodore B. Comstock, Van Nuys Bldg., Los Angeles, Cal.

Eugene Coste, 1943 11th St., West, Calgary, Alberta, Canada. Dec, 1906.

Alja Robinson Crook, State Museum of Natural History, Springfield, HI.
December, 1898.
*WiLLiAM O. Crosby, Massachusetts Institute of Technology, Boston, Mass.

Whitman Cross, U. S. Geological Survey, Washington, D. C. May, 1889.

Garry E. Culver, 1104 Wisconsin St., Stevens Point, Wis. December, 1891.

Edgar R. Cumings, Indiana University, Bloomington, Ind. August, 1901.
* Henry P. Gushing, Adelbert College, Cleveland, Ohio.

Reginald A. Daly, Harvard University, Cambridge, Mass. December, 1905.

Edward Salisbury Dana, Yale University, New Haven, Conn. Dec, 1908.
*Nelson H. Darton, U. S. Geological Survey, Washington, D. C.

Charles Albert Davis, U. S. Bureau of Mines, Washington, D. C. Dec, 1910.
*WiLLiAM M. Davis, Harvard University, Cambridge, Mass.

Arthur Louis Day, Geophysical Laboratory, Carnegie Institution, Washing-
ton, D. C. December, 1909.

David T. Day, U. S. Geological Survey. Washington, D. C. August, 1891.

Bashford Dean, Columbia University, New York, N. Y. December, 1910.

Obville A. Derby, Serv. Geol. & Mineral. d'Brazil, Praia Vermillia, Rio de
Janeiro, Brazil. December, 1890.

Frank Wilbridge De Wolf, Urbana, 111. December, 1909.
♦Joseph S. Diller, U. S. Geological Survey, Washington, D. C.

Edward V. d'Invilliers, 518 Walnut St., Philadelphia, Pa. December, 1888.

Richard E. Dodge, Teachers' College. New York, N. Y. August, 1897.

Noah Fields Drake, Fayetteville, Arkansas. December, 1898.

John Alexander Dresser. 10 Forest Ave., Saulte Ste. Marie, Ontario, Canada.
December, 1906.

Charles R. Dryer, Oak Knoll, Fort Wayne, Ind. August, 1897.
♦Edwin T. Dumble, 1306 Main St., Houston, Texas.

Arthur S. Eakle, University of California, Berkeley, Cal. December, 1899.

Charles R. Eastman, American Museum of Natural History, New York,
N. Y. December, 1895.

Edwin C. Eckel, Munsey Building, Washington, D. C. December, 1905.
♦Benjamin K. Emerson, Amherst College, Amherst, Mass.

William Harvey Emmons, University of Minnesota, Minneapolis, Minn. De-
cember, 1912.

John Eyerman, Oakhurst, Easton, Pa. August, 1891.

Harold W. Fairbanks, Berkeley, Cal. August, 1892.
♦Herman L. Faibchild, University of Rochester, Rochester, N. Y.

Oliver C. Farrington, Field Museum of Natural History, Chicago, 111. De-
cember, 1895.

Nevin M. Fenneman, University of Cincinnati, Cincinnati, Ohio. Dec, 1904.

Clarence Norman Fenner, Geophysical Laboratory, Washington, D. C. De-
cember, 1911.

LIST OF MEMBERS 121

Cassius Asa Fisher, 711 Ideal Building, Denver, Colo. December, 1908.
August F. Foerste, 128 Rockwood Ave., Dayton, Ohio. December, 1899.
Myron Leslie Fuller, 185 Spring St., Brockton, Mass. December, 1898.
Henry Stewart Gane, Wonalancet, New Hampshire. December, 1896.
James II. Gardner, 212 Clinton Bldg., Tulsa, Oklahoma. December, 1911.
Russell D. George, University of Colorado, Boulder, Colo. December, 190(3
♦Grove K. Gilbert, U. S. Geological Survey, Washington, D. C.
Adam Capen Gill, Cornell University, Ithaca, N. Y. December, 1888.
L. C. Glenn, Vanderbilt University, Nashville, Tenu. June, 1900.
James Walter Goldthwait, Dartmouth College, Hanover, N. H. Dec, 1909.
Charles H. Gordon, University Library, University of Tennessee, Knoxville,

Tenn. August, 1893.
Clarence E. Gordon, Mas.sacliusetts Agricultural College, Amherst, Mass.

December, 1913.
Charles Newton Gould, 408 Terminal Bldg., Oklalioma City, Okla. ipecem-

ber, 1904.
Amadeus W. GRABAir, Columbia University, New York, N. Y. December, 1898.
Walter Granger, American Museum of Natural History, New York, N. Y.

December, 1911.
Ulysses Sherman Grant, Northwestern University, Evanston, 111. Dec, 1890.
John Sharshall Grasty, University of Virginia, University, Va. Dec, 1911.
Louis C. Graton, Harvard University, Cambridge, Mass. December, 1913.
Herbert E. Gregory, Yale University, New Haven, Conn. August, 1901.
George P. Grimsley, Geological Survey of West Virginia, Martinsburg, W. Va.

August, 1893.
Leon S. Griswold, Plymouth, Mass. August. 1902.

Frederic P. Gulliver, 1112 Morris Bldg., Philadelphia, Pa. August, 1895.
William F. E. R. Gurley, University of Chicago, Chicago, 111. Dec, 1914.
Arnold Hague, U. S. Geological Survey, Washington, D. C. May, 1889.
Baird Halberstadt, Pottsville, Pa. December, 1909.
Gilbert D. Harris, Cornell University, Ithaca, N. Y. December, 1903.
John Burchmore Harrison, Georgetown, British Guiana. June, 1902.
Chris. A. Hartnagel, State Museum, Albany, N. Y. December, 1913.
John B. Hastings, 1480 High St., Denver, Colo. May, 1889.
*Erasmuth Haworth, University of Kansas, Lawrence, Kans.
C. Willard Hayes, 47 Parliament St., London, England. May. 1889.
Ray Vernon Hennen, West Virginia Geological Survey, Morgantown. W. Va.

December, 1914.
Oscar H. Hershey, Kellogg, Idaho. December, 1909.
Richard R. Hice, Beaver, Pa. December, 1903.
Frank A. Hill. 1315 Mahantango St., Pottsville, Pa. May, 1889.
♦Robert T. Hill, Federal Bldg., Los Angeles, Cal.
Richard C. Hills, Denver, Colo. August, 1894.

Henkv Hinds, U. S. Geological Sui-vey, Washington, D. C. December. 1912.
♦Charles II. Hitchcock, Honolulu, Hawaiian Islands.
William Herbert Hobbs, University of Micliigan, Ann .\rbor, Mich. August.

1891.
♦Levi Holbrook, P. O. Box 530, New York, N. Y.
Roy J. Holden. Virginia Polytechnic Institute, Blacksburg. Va. Dec, 1914.

122 PROCEEDINGS OF THE PHILADELPHIA MEETING

William Jacob Holland, Carnegie Museum, I'ittsburgb, Pa. December, 1910.

Arthue Hollick, Staten Island Association of Arts and Sciences, New
Brighton, S. I. August, 1898.
*JosEPH A. Holmes, U. S. Bureau of Mines, Washington, D. C.

Thomas C. Hopkins, Syracuse University, Syracuse, N. Y. December, 1894.

William Otis Hotchkiss, State Geologist, Madison, Wis. December, 1911.
* Edmund Otis Hovey, American Museum of Natural History, New Yorlc, N. Y.

Ernest Howe, 77 Rhode Island Ave., Newport, R. I. December, 1903.

George D. Hubbard, Oberlin College, Oberlin. Ohio. December, 1914.

Lucius L. Hubbard, Houghton, Mich. December, 1894.

Walter F. Hunt, University of Michigan, Ann Arbor, Mich. December, 1914.

Ellsworth Huntington, Yale University, New Haven, Conn. Dec, 1900.

Louis Hussakof, American Museum of Natural History, New York, N. Y.
December, 1910.

Joseph P. Iddings, Brinklow, Md. May. 1889.

John D. Irving, Yale University, New Haven, Conn. December, 1905.

A. Wendell Jackson, 482 Saint Nicholas Ave., New York. N. Y. Dec, 1888.

Robert T, Jackson, 195 Bay State Road, Boston, Mass. August, 1894.

Thomas Augustus Jaggar, Jr., Hawaiian Volcano Observatory, Territory of
Hawaii, U. S. A. December, 1906,

Mark S. W. Jefferson, Michigan State Normal College, Ypsilauti, Mich. De-
cember, 1904.

Edward C. Jeffrey, Harvard University. Cambridge, Mass, December, 1914.

Albert Johannsen, University of Chicago, Chicago, 111. December, 1908.

Douglas Wilson Johnson, Columbia University, New York, N. Y. Dec, 1900.

Alexis A. Juijen, South Harwich, Mass. May, 1889.

Frank James Katz. U. S. Geological Survey, Washington, D. C. Dec, 1912.

George Frederick Kay, State University of Iowa, Iowa City, Iowa. Dec, 1908.

Arthur Keith, U. S. Geological Survey, Washington, D. C. May, 1889.
*James F. Kemp, Columbia University, New York, N. Y.

Charles Rollin Keyes, 944 Fifth St., Des Moines, Iowa. August, 1890.

Edward M. Kindle, Victoria Memorial Museum, Ottawa, Canada. Dec, 1905.

Edwin Kirk, U. S. Geological Survey. Washington, D. C. December, 1912.

Cyril Workman Knight, Toronto, Ontario, Canada. December, 1911.

Adolph Knopf, U. S. Geological Survey, Washington, D. C. December, 1911.

Frank H. Knowlton, U. S. National Museum, Washington, D. C. May, 1889.

Edward Henry Kraus, University of Michigan, Ann Arbor, Mich. June, 1902.

Henry B. Kummel. Trenton. N. J. December. 1895.
*George F. Kunz, 401 Fifth Ave., New York, N. Y.

George Edgar Ladd, State College, N. M. August, 1891.

Lawrence Morris Lambe, Department of Mines, Ottawa, Canada. Dec, 1911.

Henry Landes, University of Washington, University Station, Seattle, Wash.
December, 1908.

Alfred C. Lane, Tufts College, Mass. December, 1889.

Esper S. Labsen, Jr., U. S. Geological Survey, Washington, D. C. Dec, 1914.

Andrew C. Lawson, University of California. Berkeley, Cal. May, 1889.

Willis Thomas Lee, U. S. Geological Survey. Washington, D. C. Dec, 1903.

James H. Lees, Iowa Geological Survey, Des Moines, Iowa. December. 1914.

Charles K. Leith, University of Wisconsin, Madison, Wis. Dec, 1902.

LIST OF MEMBERS 123

Abthub G. Leonard, State University of North Dakota, Grand Forks, N. Dak
December, 1901.

Frank Leverett, Anu Arbor, Mich. August, 1890.

Joseph Volney Lewis, Rutgers College, New Brunswick, N. J. Dec, 1906.

William Libbey, Princeton University, Princeton, N. J. August, 1899.

Waldemab Lindgben, Massachusetts Institute of Technology, Boston, Mass.
August, 1890.

Miguel A. R. Lisboa, Irrigation and "Water Supply Service, Rio de Janeiro,
Brazil. December, 1913.

Frederick Brewster Loomis, Amherst College, Amherst, Mass. Dec, 1909.

George Davis Louderback, University of California, Berkeley, Cal. June, 1902.

Robert H. Loughridge, University of California, Berkeley, Cal. May, 1889.

Albert P. Low, Department of Mines, Ottawa, Canada. December, 1905'.

Richard Swann Lull, Yale University, New Haven, Conn. December, 1909.

Samuel Washington McCallie, Atlanta, Ga. December, 1909.

Hiram Deyeb McCaskey, U. S. Geological Survey, Washington, D. C. De-
cember, 1904.

Richard G. McConnell, Geological and Natural History Survey of Canada,
Ottawa, Canada. May, 1889.

James Rieman Macfablane, Woodland Road, Pittsburgh, Pa. August. 1891.

WiiiiAM McInnes, Geological and Natural History Survey of Canada, Ot-
tawa, Canada. May, 1889.

Peter McKellar, Fort William, Outario, Canada. August, 1890.

George Rogers Mansfield, 2039 Park Road N. W., Washington, D. C. De-
cember, 1909.

CuBTis F. Marbut, Bureau of Soils, Washington, D. C. August, 1897.

Vebnon F. Mabsters, San Juancito, Honduras, C. A. August, 1892.

George Curtis Mabtin, U. S. Geological Survey, Washington, D. C. June, 1902.

Lawbence Martin, University of Wisconsin, Madison, Wis. December, 19U9.

Edward B. Mathews, Johns Hopkins University, Baltimore, Md. Aug., 1895.

Francois E. Matthes, U. S. Geological Survey, Washington, D. C. Decem-
ber, 1914.

W. D. Matthew, American Museum of Natural History, New York, N. Y.
December, 1903.

Thomas Poole Maynard, 1622 D. Hurt Bldg., Atlanta, Ga. December, 1914.

P. H. Mell, 105 East 10th St., Atlanta, Ga. December, 1888.

Walter C. Mendenhall, U. S. Geological Survey, Washington. D. C. June,
1902.

John C. Mebbiam, University of California, Berkeley, Cal. August, 1895.
♦Frederick J. H. Merrill. 624 Citizens' National Bank Bldg.. Los Angeles, Cal.

George P. Merrill, U. S. National Museum, Washington. D. C. Dec, 1888.

Herbert E. Mebwin, Geophysical Laboratory, Washington, D. C. Dec, 1914.

Arthur M. Miliar, State University of Kentucky, Lexington. Ky. Dec. 1897.

Ben.iamin L. Millkk, Lehigh University. South Bethlehem, I'a. Dec, T.hH.

WiLLKT (J. Miller, Toronto, Canada. Decomlicr, 1!M)2.

William John Millkk, Smith College, Nortliaiiii)(ou, Ma.ss. December, 1909.

Fred Howard Moi'mt, U. S. Geological Survey, Washington, D. C. Det-., 1912.

(J. A. F. MoLENGRAAF, T<'chuical High School, I>elft, Holland. Decemlier. 19i:{.

Henuy Montgomery, University of Toronto, Toronto, Canada. Dec, 1904.

124 PROCEEDINGS OP THE PHILADELPHIA MEETING

Elwood S. Moore, Pennsylvania State College, State College, Pa. Dec, 1911.

Malcolm John Munn, Clinton Bldg., Tulsa, Okla. December, 1909.
♦Frank L. Nason, West Haven, Conn.

David Hale Newland, Albany, N. Y. December. 190G.

John F. Newsom, Leland Stanford, Jr., University, Stanford University, Cai.
December, 1899.

William II. Norton, Cornell College, Mount Vernon, Iowa. December, 1895.

Charles J. Norwood, State University, Lexington, Ky. August, 1894.

Ida Helen Ogilvie, Barnard College, Columbia University, New York, N. Y.
December, 1906.

Cleophas C. O'Harra, South Dakota School of Mines, Rapid City, S. Dak.
December, 1904.

Daniel Webster Ohern, University of Oklahoma, Norman, Okla. Dec, 1911.

Ezequiel Ordonez, 2 a General Prim 43, Mexico, D. F., Mex. August, 189(5.

Edward Orton, Jr., Geological Survey of Ohio, Columbus, Ohio. Dec, 1909.

Henry F. Osborn, American Museum of Natural Histoi-y, New York, N. Y.
August, 1894.

Sidney Paige, U. S. Geological Survey, Washington, D. C. December, 1911.

Charles Palache, Harvard University, Cambridge, Mass. August. 1897.

William A. Parks, University of Toronto, Toronto, Canada. December, 190t>.
♦Horace B. Patton, Colorado School of Mines, Golden, Colo.

Frederick B. Peck, Lafayette College, Easton, Pa. August, 1901.

Richard A. F. Penrose, Jr., 460 Bullitt Bldg., Philadelphia, Pa. May, 1889.

George H. Perkins, University of Vermont, Burlington, Vt. ; State Geologist.
June, 1902.

Joseph H. Perry, 276 Highland St., Worcester, Mass. December, 1888.

Olaf August Peterson, Carnegie Museum, Pittsburgh, Pa. December. 1910.

William Clifton Phalen, U. S. Geological Survey, Washington, D. C. De-
cember, 1912.

Alexander H. Phillips, Princeton University, Princeton, N. J. Dec, 1914,

Louis V. Pihsson, Yale University, New Haven. Conn. August. 1894.

.Joseph E. Pogue, Northwestern University, Evanston, 111. December, 1911.

Joseph Hyde Pratt, North Carolina Geological Survey, Chapel Hill, N. C.
December, 1898.

Louis M. Prindle, U. S. Geological Survey, Washington, D. C. Dec, 1912.
♦Chaeles S. Prosser, Ohio State University, Columbus, Ohio.

William Frederick Prouty, University of Alabama, University, Ala. De-
cember, 1911.
♦Raphael Pumpelly, Newport, R. I.

Albert Homer Purdue, State Geological Survey, Nashville, Tenn. Dec, 1904.

Frederick Leslie Ransome, U. S. Geological Survey, Washington, D. C. Au-
gust, 1895.

Percy Edward Raymond, Museum of Comparative Zoology, Cambridge, Mass
December, 1907.

Chester A. Reeds, American Museum of Natural History, New York, N. Y.
December, 1913.

Harry Fielding Reid, Johns Hopkins University, Baltimore, Md. Dec, 1892.

William North Rice, Wesleyan University, Mlddletown, Conn. August, 1890.

John Lyon Rich, University of Illinois, Urbana, 111. December, 1912.

LIST OF MEMBERS 125

Charles H. Richardson, Syracuse University, Syracuse, N. Y. Dec, 1899.
George Burr Richardson, U. S. Geological Survey, Washington, D. C. De-
cember, 1908.
Heinrich Ries, Cornell University, Ithaca, N. Y. December, 1893.
Elmer S. Riggs, Field Museum of Natural History, Chicago, 111. Dec, 1911.
Jesse Terry Rowe, University of Montana, Missoula, Mont. December, lUll.
Rudolph Ruedemann, Albany, N. Y. December, 1905.
John Joseph Rutledge, Experiment Station, Pittsburgh, Pa. Dec, 1911.
Orestes H. St. John, 1111 Twelfth St., San Diego, Cal. May, 1889.
*Rollin D. Salisbury, University of Chicago, Chicago, 111.
Frederick W. Sardeson, University of Minnesota, Minneapolis, Minn. De

cember, 1892.
Thomas Edmund Savage, University of Illinois, Urbana, 111. December, 1907.
Frank C. Schrader, U. S. Geological Survey, Washington, D. C. Aug., 1901.
Charles Schuchert, Yale University, New Haven, Conn. August, 1895.
Alfred Reginald Schultz. U. S. Geological Survey, Washington, D. C. De-
cember, 1912.
William B. Scott, Princeton University, Princeton, N. J. August, 1892.
Arthur Edmund Seaman, Michigan College of Mines, Houghton, Mich. De-
cember, 1904.
Henry M. Seely, Middlebury College, Middlebury, Vt. May, 1889.
Elias H. Sellards, Tallahassee, Fla. December, 1905.
JoAQUiM Candido da Costa Sena, State School of Mines, Ouro Preto. Brazil.

December, 1908.
Millard K. Shaler, 4 Bishopsgate E. C, London, England. December, 1914.

George Burbank Shattuck, Vassar College, Poughkeepsie, N. Y. Aug., 1899.

Eugene Wesley Shaw, U. S. Geological Survey, Washington, D. C. Dec, 1912.

Solon Shedd, State College of Washington, Pullman, Wash. Dec, 1904.

Edward M. Shepabd, 140.3 Benton Ave., Springfield, Mo. August, 1901.

Will H. Sherzer, State Normal School, Ypsilanti, Mich. December, 1890.

Bohumil Shimek, University of Iowa, Iowa City, Iowa. December, 1904.

Hervey Woodbubn Shimeb, Massachusetts Institute of Technology, Boston,
Mass. December, 1910.

Claude Ellsworth Siebenthal, U. S. Geological Survey, Washington, D. C.

December, 1912.
♦Frederick W. Simonds, University of Texas. Austin, Texas.

William .John Sinclair, Princeton University, I'rinceton, N. J. Dec, 1900.

Joseph Theophilus Singewald, Johns Hopkins University, Baltimore, Md.
December, 1911.

Earle Sloan, Charleston, S. C. December, 1908.

Burnett Smith, Syracuse University, Skaneateles, N. Y. December, 1911.

Carl Smith, U. S. Geological Survey, Washington, D. C. December, 1912.
♦Eugene A. Smith, University of Alabama, University, Ala.

George Otis Smith, U. S. Geological Survey, Washington. D. C. •\ug.. 1897.

Phtlip S. Smith, U. S. (Jeological Survey. Washington. D. C. Dec, llKl'.t.

Warren I)u 1'k6 Smith, University of Uregt)n. Eugene, Oregon. Dec, llK«t.

W. S. Tangier Smith, Lodi, Cal. June, 1902.
♦John C. Smock, Trenton, N. J.

Charles H. Smyth, Jr., Princeton University, Princeton, N. J. .\ug.. 1892.

126 PROCEEDINGS OF THE PHILADELPHIA MEETING

Henry L. Smyth, Harvard University, Cambridge, Mass. August. 1894.
Arthur Coe Spencer, U. S. Geological Survey, Washington, D. C. Dec, 1896.
*J. W. Spencer, 2019 Hillyer Place, Washington, D. C.
Frank Springer, U. S. National Museum. Washington, D. C. December. 1911.
JosiAH E. Spurr, Bullitt Bldg., Philadelphia, Pa. December, 1894.
Joseph Stanley-Brown, 26 Exchange Place, New York, N. Y. August, 1892.
Timothy William Stanton, U. S. National Museum, Washington, D. C. Au-
gust, 1891.
Clinton Raymond Stauffer, University of Minnesota, Minneapolis, Miim.

December, 1911.
Lloyd William Stephenson, U. S. Geological Survey, Washington, D. C. De-
cember, 1911.
*John J. Stevenson, 215 West 101st St., New York. N. Y.
Ralph Walter Stone, U. S. Geological Survey, Washington, D. C. Dec, 1912.
George Willis Stose, U. S. Geological Survey, Washington, D. C. Dec, 1908.
William J. Sutton, Victoria, B. C. August, 1901.

Charles Kephart Swaetz, Johns Hopkins University, Baltimore, Md. De-
cember, 1908.
Stephen Taber, University of South Carolina, Columbia, S. C. Dec, 1914.
Joseph A. Taff, 781 Flood Building, San Francisco, Cal, August, 1895.
MiGNON Talbot, Mount Holyoke College, South Hadley, Mass. Dec, 1913.
James E. Talmage, University of Utah, Salt Lake City, Utah. Dec, 1897.
Frank B. Taylor, Fort Wayne, Ind. December, 1895.
*James E. Todd, 1224 Rhode Island St., Lawrence, Ivans.

Cyrus Fisher Tolman, Jr., Leland Stanford, Jr., University, Stanford Uni-
versity, Cal. December, 1909.
Arthur C. Trowbridge, State University of Iowa, Iowa City, Iowa. Decem-
ber, 1913.
*IIenry W. Turner, 209 Alaska Commercial Building, San Francisco, Cal.
William H. Twenhofel, University of Kansas, Lawrence, Kaus. Dec, 1913.
Mayvilij: William Twitchell, State Geological Survey, Trenton, N. J. De-
cember, 1911.
Joseph B. Tyrrell, Room 534, Confederation Life Building, Toronto, Canada.

May, 1889.
JoHAN A. Udden, University of Texas, Austin, Texas. August, 1897.
Edward O. Ulrich, U. S. Geological Survey, Washington, D. C. Dec, 1903.
Joseph B. Umpleby, U. S. Geological Survey, Washington, D. C. Dec, 1913.
*Warben Upham, Minnesota Historical Society, Saint Paul, Minn.
♦Charles R. Van Hise, University of Wisconsin, Madison, Wis.
Frank Robertson Van Horn, Case School of Applied Science, Cleveland.

Ohio. December, 1898.
Gilbert van Ingen, Princeton University, Princeton, N. J. December, 1904.
Thomas Wayland Vaughan, U. S. Geological Survey, Washington, D. C. Au-
gust, 1896.
Arthur Clifford Veach, 7 Richmond Terrace, Whitehall, S. W., London,

England. December, 1906.
♦Anthony W. Vogdes, 2423 First St., San Diego, Cal.

*M. Edward Wadsworth, School of Mines, University of Pittsburgh, Pitts-
burgh, Pa,

LIST OF MEMBERS 127

*Chari,es D. Walcott, Smithsonian Institution. Washington, D. C.

Thomas L. Walker, Univei-sity of Toronto, Toronto, Canada. Dec. 1003.

Charles H. Warren. Massachusetts Institute of Technology. Boston, Mass.
December, 1901.

Henry Stephens Washington, Geophysical Laboratory, Washington, D. C.
August, 1896.

Thomas L. Watson, University of Virginia, Charlottesville. Va. June. 1900.

Charles E. Weaver, University of Washington, Seattle, Wash. Dec, lOlo.

Walter H. Weed, 29 Broadway, New York, N. Y, May, 1889.

Carroll Harvey Wegemann, U. S. Geological Survey, Washington. D. C. De-
cember, 1912.

Samuel Weidman, Wisconsin Geological and Natural History Survey, Madi-
son, Wis. December, 1903.

Stuart Weller, University of Chicago, Chicago, 111. June, 1900.

Lewis G. Westgate, Ohio Wesleyan University, Delaware, Ohio.

David White, U. S. National Museum, Washington, D. C. May, 1889.
♦Israel C. White, Morgantown, W. Va.

George Reber Wieland, Yale University, New Haven, Conn. December, 1910.

Frank A. Wilder, North Holston, Smyth County, Va. December, 1905.
♦Edward H. Williams, Jr., Woodstock, Vt.
♦Henry S. Williams, Cornell University, Ithaca, N. Y.

Ira a. Wiluams, Oregon School of Mines, Corvallis, Ore. December, 1905,

Bailey Willis, U. S. Geological Survey, Washington, D. C. December, 1889

Alfred W. G. Wilson. Department of Mines, Ottawa, Canada. June, 1902.

Alexander N. Winchell, University of Wisconsin, Madison, Wis. Aug., 1901.
♦Horace Vaughn Winchell, 505 Palace Building, Minneapolis, Minn.
♦Arthur Winslow, 131 State St., Boston, Mass.

John E. Wolff, Harvard University, Cambridge, Mass. December, 1889.

Joseph E. Woodman, New York University, New York, N. Y. Dec. 1905.

Robert S. Woodward, Carnegie Institution of Washington, Washington, D. C.
May, 1889.

Jay B. Woodworth, Harvard University, Cambridge, Mass. December. 1895.

Charles Will Wright, Ingurtosu. Arbus, Sardinia, Italy. December, 1909.

Frederic E. Wright, Geoph.ysical Laboratory, Carnegie Institution, Washing-
ton, D. C. December, 1903.
♦G. Frederick Wright, Oberlin Theological Seminary, Oberlin. Ohio.

George A. Young, Geological Survey of Canada, Ottawa, Canada. Dec, 1905.

CORRESPONDENTS DECEASED

Hkrmax CREDNiiR. Died July 22. 1013. Edward Subss. Died April 20, 1914.

.\. MicHEL-LfivY.. Died September, 1011. Th. Tscherny.schew. Died .Tan. 1.5, 1014.

H. RosKNBi'.scH. Died .January 20, 1914. Ferdinand Zerkel. Died June 11. 1012.

FELLOWS DECEASED

* IndicafpR Original Fellow (see article III of Constitution)

♦CiiA.s. A. AsHBORNER. Died Dcc. 24, 1880. Amos Bowman. Died Juno IS, 1S04.

Alfred E. Barlow. Died May 28. 1014. Erxesst R. Buckley. Died Jan. 10. 1012.

riiARLKs E. Beecher. Died Feb. 14, 1004. *Samhel Calvin. Died April 17. 1011.

Albert S. BiPKMORE. Died ;\uk. 12, 1014. Franklin R. Carpenter. Died April 1,
Wm. Phipps Blake. Died May 21, 1910. 1910.

128

PROCEEDINGS OF THE PHILADELPHIA MEETING

*.T. H. Chapin. Died March 14, 1892.
*Edward W. Claypole. Died Aug. 17, 1901.

George H. Cook. Died Sept. 22, 1889.
♦Edward D. Cope. Died April 12. 1897.

Antonio Del Castillo. Died Oct. 28, 1895.
*.Ta.mes D. Dana. Died April 14. 189.5.

George M. Dawson. Died March 2, 1901.

Sir .T. Wm. Dawson. Died Nov. 19. 1899.

Clarence E. Ddtton. Died .Tan. 4, 1912.
♦WiLLiA.M B. DwiGHT. Died Aug. 29, 1906.
♦George H. Eldridge. Died .Tune 29, 190."i.
♦Samuel P. Emmons. Died March 28, 1911.

W.M. M. Fontaine. Died April 29, 1913.
♦Albert E. Foote. Died October 10, 1895.
♦Persifor Frazer. Died April 7, 1909.
♦Homer T. Fuller. Died Aug. 14, 1908.

N. .T. GiROU-X. Died November .30. 1891.
♦Christopher W. Hall. Died May 10, 1911.
♦.Tames Hall. Died August 7, 1898.

.ToHN B. Hatcher. Died .Tuly S, 1904.
♦Robert Hay. Died December 14, 189,5.
♦Angelo Heilpkin. Died .Tuly 17, 1907.

David Honeyman. Died October 17, 1889.
Died April 16, 1911.
Died .Tuly 27, 1914.
Died Feb. 12, 1892.
Died Jan. 15, 1902.

Thomas M. Jackson. Died Feb. 3, 1912.
♦Joseph F. James. Died March 29, 1897.

Wilbur C. Knight. Died .Tuly 28, 1903.

Ralph D. Lacoe. Died February 5. 1901.

J. C. K. Laflamme. Died July 6. 1910.

Daniel W. Langton. Died .Tune 21, 1909.
♦Joseph IvE Conte. Died July 6, 1901.
* J. Peter Lesley. Died June 2, 1903.

♦Edwin B. Howell.
♦Horace C. Hovey.
Thomas R. Hunt.
♦Alpheus Hyatt.

Henry McCalley. Died Nov. 20, 1904.
♦W J McGee. Died September 4, 1912.

Oliver Marcy. Died March 19, 1899.

Othniel C. Marsh. Died March 18, 1899.

.Tames B. Mills. Died July 25, 1901.
♦Henry B. Nason. Died .Tanuary 17, 1895.
♦Peter Neff. Died May 11, 1903.
♦John S. Newberry. Died Dec. 7, 1892.

Willia.m H. Niles. Died Sept. 12, 1910.
♦Edward Orton. Died October 16, 1899.
♦Amos O. Osborx. Died March, 1911.
♦Richard Owen. Died March 24, 1890.

Samuel L. Penfield. Died Aug. 14. 1906.

David P. Penh.\llow. Died Oct. 20. 1910.
♦Franklin Platt. Died July 24, 1900.

William H. Pettee. Died May 26, 1904.
♦.Tohn W. Powell. Died Sept. 23, 1902.
♦Israel C. Russell. Died May 1. 1906.
♦Ja.mes M. Safford. Died July 3, 1907.
♦Charles Schaeffer. Died Nov. 23, 1903.
♦Nathaniel S. Shaler. Died April 10, 1906.

Ralph S. Tarr. Died March 21. 1912.

William G. Tight. Died .Tan. 15, 1910.

Charles Wachsmuth. Died Feb. 7. 1896.

Thomas C. Weston. Died .Tuly 20. 1910.

Theodore G. White. Died July 7, 1901.
♦Robert P. Whitfield. Died April 6, 1910.
♦George H. AVilliams.
♦J. Francis Williams.

Arthur B. Wilmott.
♦Alexander Winchell.
♦Newton Winchell.

Died July 12, 1894.
Died Nov. 9, 1891.
Died May 8, 1914.
Died Feb. 19, 1891.
Died May 1, 1914.

Albert A. Wright.
William S. Yeates.

Died April 2. 1905.
Died Feb. 19, 1908.

Summary

Correspondents 10

Original Fellows 46

Elected Fellows 334

Member.ship 390

Deceased Correspondents 6

Deceased Fellows 78

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA
Vol. 26, pp. 129-140 March 31, 1915

PEOCEKDINGS OF THE FIFTEENTH ANNUAL MEETING OF
THE CORDILLERA N SECTION OF THE GEOLOGICAL SO-
CJKVY OF AMEIH(L\, HELD AT SEATTLE, AVASHINGTON,
MAY 31 AND 32, 1914.^

George D. Loudekback, Secretary

CONTENTS

Page
Session of Thur.sday, May 21 180

Pre-Pleistocene geology in tlie vicinity of Seattle [abstract and
fliscn.ssion] : by Charles E. Weaver 1?,0

Pleistocene of vrestern Washington [abstract] ; by Charles E.

Weaver 131

Election of officers 131

Summer meeting 131

Affiliation with the American Association for the Advancement of
Science 132

Structure of Pierce County coal field of Washington [abstract
and discussion] ; by Joseph Daniels 132

Tertiary rocks of Oahu [abstract and discus.sion] ; by C. H. Hitch-
cock 13'.

Pea for uniformity and simplicity in petrologic nomenclature [ab-
stract and discussion] ; by G. Montague Butler 134

Session of Friday, May 22 135

Geologic structure in western Washington [abstract and discus-
sion] ; by Charles E. Weaver 135

Eocene of the Cowlitz Valley, Washington [abstract and discus-
sion] ; by Charles E. Weaver 136

Relation of the Tertiary geological scale of the Great Basin to
that of the Pacific Coast marginal province [abstract and dis-
cussion] ; by J. C. Merriam 136

Relation between the Tertiary sedimentaries and lavas of Kittitas
County, Washington [abstract]; by E. J. Saunders 137

Oregon Bureau of Mines and Geology [abstract and discussion] ;
by Ira A. Williams 137

R61e of sedimentation in diastrophism and vulcani.sm; by F. M.
Handy 13S

Basin Range faulting in the northeastern part of the Great Basin

[abstract] ; by George D. Louderback 138

1 Manuscript received by the Secretary of the Geological Society .June 22, 1014.

(129)

130 ■ proceedings of the cordilleran section

Session of Thursday, May 21

The Fifteenth Annual Meeting of the Cordilleran Section of the
Geological Society of America was held in conjunction with the Pacific
Association of Scientific Societies, at the University of Washington,
Seattle, Washington, j\Iay 21 and 23, 1914, in room 3, Science Hall. In
the absence of the cliairman, the meeting was called to order at 10.15
a. m. by the secretary of the section. Prof. A. C. Lawson was elected
temporary chairman.

It was voted that the business session be held at 1.30 p. m., and that
the morning be devoted to the "reading of scientific papers. The secre-
tary reported that the nominations sent in by mail were too scattering
to definitely indicate a nomination for chairman for the ensuing year,
and moved that a nominating committee be appointed to report at the
business session. The motion was seconded and carried and the tem-
porary chairman a]ipoiiit(Ml Londerback, Weaver, and Saunders as such
committee.

The following papers were then presented in the order given:

PRE-PLEISTOCENE GEOLOGY IN THE VICINITY OF SEATTLE '
BY CHARLES E. WEAVER

(Ahstract)

The larger part of Seattle is heavily covered over with deposits of glacial
drift. From the western foothills of the Cascades a prominent structural up-
\\arp extends northwesterly through Seattle into Kitsap County. Along the
axis of this uplift the older Tertiary formations are exposed. They consist
of approximately 4,000 feet of EJocene sedimentaries and volcanics containing
a Tejon fauna and productive coal measures. Overlying these are at least
7.000 feet of Lower Miocene sandstones and shales. These strata have been
folded. A prominent anticlinal axis extends along the line of uplift. On the
north and south flanks of this fold north and south minor anticlinal and
synclinal folds have been developed. During the late Tertiary these were sub-
jected to vigorous erosion and during the Pleistocene were glaciated.

Presented from notes and illustrated by geologic map.

Discussion

In reply to question by Mr. Bretz. the author explained that the south limb
of the anticline was covered and its detailed structure not known. Answering
question by Merriam, he stated that the Miocene involved includes the lowest
zone. In reply to question by Londerback, author held that there were no pre-
Eooene lavas involved, as at certain localities fossiliferous Eocene strata are
found below the lowest lavas.

ABSTRACTS OF PAPERS 131

PLEISTOCENE OF WESTERN ^7ASHIN(JT0N
BY J. HARLEN BRETZ

(Abstract)

An early Pleistocene gravel deposit, the Satsop formation, is widely dis-
tributed along the Washington coast and In the Chehalis Valley. The Satsop
formation Is not found in the Puget Sound region, where glacial deposits cover
most of the country.

Two glaciations are known in western Washington — the Admiralty and the
Vashon. A thick formation of stratified drift, the Admiralty sediments, was
deposited during the retreat of the Admiralty ice. During the succeeding
inter-Glacial epoch the Puyallup epoch, these deposits were eroded by streams
to form valleys now constituting Puget Sound. No truly interglacial deposits
are known in Puget Sound. The region appears to have been fully a thousand
feet higher during this inter-Glacial epoch than during the preceding Admiralty
or the following Vashon epochs.

The Vashon glacier failed throughout most of the region to modify materi-
ally the topography produced during the Puyallup epoch. During its retreal
a series of glacial lakes formed in the valleys of inter-Glacial age. The region
at this time lay 50 or 75 feet lower than at present.

Postglacial diastrophism embraces a complete oscillation of the Puget Sound
region, the sea having stood at least 290 feet above present tide at some time
subsequent to the Vashon epoch.

Except for outwash of both Admiralty and Vashon age in certain valleys
of the Chehalis system, no events other than stream erosion are known to
record the later Pleistocene epochs in southwestern Washington.

Presented without notes and illustrated by lantern slides.
The author replied to several questions raised by Lawson.

The section adjourned for lunch at 11.55 to reconvene at 1.30.

The afternoon session was called to order by the temporary chairman
at 1.55, and the minutes of the Fourteenth Annual Session were read
and approved.

ELECTION OF OFFICERS

After the report of the Nominating Committee, fho fol having were
elected as section officers for the year 1914-1915 :

H. Poster Bain^ Chairman.
George D. Louderback, Secretary.
• Charles E. Weaver, Councilor.

RUMMER MEETINC

The secretary announced the decision of the Geological Society of
America to accept the invitation of the ( 'ordillcraii Section and hold a
X— Bull. Gkol. Soc. Am., Vol. -tl, r.»14

132 FROCEEDINGS OF THE COROILLERAN SECTION

special session in California in August, 1915. It is planned to hold the
meetings at the University of California, Berkeley, and at least one
session at Stanford University. In consideration of this, the section
voted to hold no separate meeting in 1915, but to use its efforts to make
the meeting of the General Society a success.

AFFILIATION WITH THE AMERICAN ASSOCIATION FOR THE ADVANCEMENT

OF SCIENCE

The secretary announced the proposed organization of a Pacific Di-
vision of the American Association for the Advaucement of Science and
explained its constitution, and also brought up the matter of affiliation
of the Cordilleran Section with this Pacific Division. It was pointed out
that, according to the constitution of the Pacific Division, if the Cor-
dilleran Section became affiliated, no geological section would be estab-
lished by the division; but that programs in geology and the organization
of geology on the coast would be left entirely in the hands of the Cor-
dilleran Section; also that the section would not be obliged to meet with
the division if in its judgment it would be better for the coast geologists
to meet elsewhere or at a different time; also that it would in no way
effect the section's relationship to the Geological Society of America.

The section voted in favor of affiliation with the Pacific Division of
the American Association for the Advancement of Science, gave its dele-
gates full power to act, and to sign the constitution if in their judgment
the rights and position of the section were fully protected.

It was voted that, if the chairman of the section was not present to
represent the section at the Pacific Association's Executive Committee
Meeting, the temporary chairman be given the above powers to represent
and act for the section.

There being no further business, the scientific program was taken up
and the following papers presented:

STRUCTURE OF PIERCE COUNTY COAL FIELD OF WASHINGTON

BY JOSEPH DANIELS

(Abstract)

The Pierce County coal field, the Puyer formation of Eocene age, consists
of a broad, abnormal anticlinorium, having a main persistent anticlinal axis
and a series of minor anticlinal and synclinal axes, all of which pitch to the
north. A known series of 12.000 to 14,000 feet is thus exposed in a chain of
isolated mines which develop the seams along a north-south line, thus exposing
the upper part of the series in the northern mines and the lower part in the
southern portion of the field. The flexing of the strata has been accompanied

AP.STRACTS OF PAPERS 133

by overtbrust faulting giving displacement of 1,500 feet, and normal faulting
isbowing horizontal displacement of 1,200 feet.

Presented from notes and illustrated by maps and seciiuns.

Discussion

In reply to question by Professor Lawson, autbor stated tbat tbe so-called
pivotal faults were in form as if produced by rotation of block about a pivot,
but really not so formed. Answering question by Louderback, he explained
tbat all of tbe faults described were thrust faults, except the two major
normal faults; also that faults were more abundant on the steeper limbs of
the anticlines.

TERTIARY ROCKS OF OAHU
BY C. H. HITCHCOCK

i Abstract)

Basalt constitutes the foundations of the mountains of the Waianae and
Koolau ranges, reaching the altitudes of 4.000 and .3,.300 feet. The first named
occupy the southwest bordei- and the second named extend parallel to the
eastern coast. The sedimentary- members rest on the Koolau range, dipping
gently to the southwest. The sides of both ranges near the ocean are precipi-
tous, the one having been eroded by storms from the southwest and the other
by the trade-wind rains from the northeast. The rainfall may exceed 175
inches on the summits and diminish to 2 or .3 feet adjacent to the ocean.
There are sediments attaining a thickness of 1,000 feet resting on the basalt,
as made known by well borings. The water flows from the base of the sedi-
ments, rising 30 to 40 feet above the sealevel.

The uppermost rock is limestone carrying many oyster-shells of Ostrcd
rctusa Sby., now extinct, and therefore esteemed to be of Pliocene age. No
other .shell has yet been -proved to be extinct. Below the limestone is a coarse
conglomerate more or less continuous from Diamond Head to near Barbers
Point. Beneath the conglomerate are masses of clay and volcanic ashes ex-
tending to the base of the scries. The succession of strata is not uniform in
contiguous wells. As a rule, limestones abound near the top and the clays near
the bottom.

The government is endeavoring to establish a dry dock on the eastern of
the Pearl River locks. Borings indicate that the materials i)enetrated consist
of volcanic ashes, loose limestones, clays, silts, and other fluviatile deposits.
The ashes came from the extinct craters Makalapa and Salt Lake to the
northeast.

After the dry dock had been completed the water was pumped out and the
cement floor aijd sides were not strong enough to prevent rupture by the
pressure from below. As firm rock can not be reached within 500 feet from
the snrfac<>. a niucb stronger ccnicnt liaso must 1)0 built into tbe floor and
walls to resist the pressure from below.

Dikes of basalt penetrate tiie lavas alotig tin- sumnul of lin' Kool.iu range

134 PROCEEDINGS OF THE CORDILLERAN SECTION

and act as dams to prevent tbe flow of water from the east to the west, as now
iin<lprstood.

There are more than 400 artesian wells in the area of tlie Plioeene sediments.

Paper presented witlioiit notes.

Discussion

In I'eply to question by Doctor Merriam, author discussed the number of
species represented in tlie supposed Plioeene, and claimed that only one was
definitely known to be extinct. Answering questions by Louderback, he said
that no deeper strata of possibly earlier age are known, and that no fauna
similar to the Ostrca retusa existed on the islands at the present time.

Professor Lawson pointed out that the water found behind the dikes might
not be diverted flows, but natural reservoirs in which water was standing at
the time it was tapped, and compared some mine waters found behind gouge.

PLEA FOR UNIFORMITY AND SIMPLICITY IN PETROLOOIC NOMENCLATURE

BY G. MONTAGUE BUTLER

(Abstract)

In the nomenclature of no other science is there probably so much confusion
and uncertainty as in petrology and petrography. This is especially true as
regards the macroscopic classification of igneous rocks.

A practical system is a necessity to mining engineers and field geologists, and
uniformity of nomenclature is undoubtedly highly desirable. The Geological
Society of America can well consider and decide this matter, as it has done in
the case of fault nomenclature.

The classification adopted should fulfill the following conditions :

1. The terms used should be old, well known ones so far as possible, and
the meanings assigned to them should correspond with common usage where .
this is practicable.

2. The distinctions should be based only on features readily recognizable in
the field.

H. The meanings attached to the various names should not be so compre-
hensive as to vitiate the usefulness of such names.

4. The classification should be of such a nature that it may be readily ex-
tended, so as to include rocks whose identification depends on microscopic
iin estigation.

Such a classification is offered. In it the igneous rocks are divided accord-
ing to textural distinctions, which result from solidification under different
conditions into three series, and the criteria of each series are given.

The identification of individual rock species is then based on the recognition
of constituent minerals, and in the case of aphanitic rocks on color luster and
other features.

In conclusion, the practical value of the conception of rock types is pre-
sented and the placing of emphasis on such types is defended, although it is
admitted that precautions must be taken to prevent the growtli of misconcep-
tiims in the minds of students when this practice is followed.

Eead from manuscript.

ABSTRACTS OF PAPERS 135

Discussion

I'rofessor Louderback poiuted out that while all recognized the desirability
(if uniformity, the dithculty was in agreeing on any uniform system. The
system i)roiJOsed by the athor is not strictly a jjeti-ologic system, but a tiekl
flassiticatiou, and the question arises as to wliether such classification is to be
complete in itself or shall simply attempt to approximate a more refined classi-
fication, which latter shall determine the definitions. In the former case the
names used by author might each ha\e two definitions, thus perpetuating con-
fusion. In the latter case the field classification would be merely approximate
and temporary until more accurate determination could be made. It was also
pointed out that the strict use of the author's tables would yield results at
\ariance with the standard nomenclature based on microscopic and chemical
analysis. Tlie great bulk of the andesitcs — the augite andesites, for example —
would by the table be placed among the basalts. The table uses physical
characteristics for major groups, but uses names based on field occurrence,
and instances were cited of common western types where volcanic fiows would
be called intrusives and vice versa. Agreement was bad with the author that
an oversimplified system, such as has been presented by certain American
petrographers for field u.ses, is of no practical value. It slurs over important
distinctions which can usually easily be made.

The meeting adjourned for the day at 4.15 p. m.

Sessiof of Friday, May 33.

The meeting was called to order at 9.55 a. m. by the chairman, Presi-
dent Branner, and the scientific program was continued as follows :

GEOLOaiC STRUCTURE IN WESTERN WASHINGTON
BY CHARLES E. WEAVER

i Abstract)

The geologic structure in western Washington consists of three nearly par-
allel predominant upwarps and three intervening downfolds extending from
the Cascade Mountains to tlie Pacific Ocean. Major and minor anticlinal and
synclinal folds have been developed parallel and ti-ansverse to these. The pre-
dominating trend of all folds in the western half of the State and on Van-
couver Island is approximately north 60° west. The minor folds on tlie flanks
of the major folds are nearly north and .south. The iiiKiation of movements
producing such strucliire appears to have been al or near (lie dose of (be
Juras.sic. It was intensified toward the close of ibc Tertiary.

Presented uithouL Jioles and illusiniird l.v si iml uml niiips.

136 PROCEEDINGS OF THE CORDIT^LERAN SECTION

Discussion

Professor Louderback asked to have explained the relation between the
northwest-southeast axes of folding and the Cascade uplift, in particular
whether they might not correspond to pre-Sierran deformation and Sierran
faulting in the Oalifurnia region. The author replied tliat lie believed they
were formed cuntemporaueously and as parts of the same general movement.

EOCENE OP THE COWLITZ VALLEY, WASHINGTON
BY CHARLES E. WEAVER

{Abst7'act)

The Eocene of Washington is extensively developed in that portion of the
Cowlitz Valley situated in Lewis and Cowlitz counties. From the town of
Wiuloek southward to Castle Rock there is a series of interbedded marine,
brackish water and fresh water sediments having a thickness of at least 8,000
feet. These strata have a northwest to southeast strike, with a low dip to the
northeast. In the lower portion of the series numerous layers of basaltic lava
and tuff are intercalated. About one mile north of Vader a minor local fold
has been developed on the northeasterly pitching flank of the series. On the
basis of marine faunas, no distinction can be made between the upper and
lower portion of the formation. The fauna is typically Tejon.

Presented without notes and illustrated by diagrams and maps.

Discussion

Doctor Branner expressed his approval of the fact that the author used the
engineer's methods of determining the relative positions of the outcrops studied
instead of relying on maps that could not be depended on.

RELATION OF THE TERTIARY QEOLOGICAL SCALE OF THE GREAT BASIN TO
THAT OF THE PACIFIC COAST MARGINAL PROVINCE

BY J. C. MERRIAM

[Ahsti-act)

Although we are acquainted with the nearly complete series of geological
formations on both sides of the Sierra Cascade Range, there are very few
places at which any definite connection between the two sets of deposits has
been recognized. A satisfactory interpretation of West American Geology
must include reasonably certain determination of the time relations between
tlie Great Basin and the marginal marine provinces.

Correlation between the two regions is based partly on lithologic evidence,
partly on the study of crustal movements and on the evidence of paleontology.
The paleontologic materials used in these correlations up to the present time
have been almost exclusively plant remains. Very recently remains of land
vertebrates found in the marginal marine province have offered an exceptional
opportunity for correlation.

ABSTRACTS OF PAPERS 137

The present paper presents a summation of the results in the study of this
problem.

Presented without notes and illustrated by lantern slides.

Discussion

111 reply to question by Professor Louderback, the author stated that the
Rattlesnake of eastern Oregon corresix)nds to the Jaealitos of the Goalinga
district, California.

RELATION BETWEEN THE TERTIARY SEDIMENTARIE8 AND LAVAS IN
KITTITAH COUNTY, WASHINGTON

BY E. J. SAUNDEBS

Presented from notes and illustrated hy maps and sections.

Discussion

Doctor Bkanner asked as to the occurrence of coal in relation to the for-
mations described. Doctor Merriam asked if the base of the Keechelus were
older than the EUenburg basalt. Mr. Weaver suggested that the Keechelus
may there represent part of the series, due to overlapping. In reply to ques-
tion by Professor Lawson as to size of dikes, the author stated that they
ranged from at)out 3 to 40 feet thick, and the space occupied by them may
represent 10,000 to 20,000 feet. The mechanism by which this amount of space
was made available was not clear. The dikes lie across the axes of the folds.

The section adjourned at 12.10 for lunch.

The meeting was resumed at 1.48 p. m., with Chairman Braiiner in
the chair, and proceeded with the scientilic program as follows :

OREQON BUREAU OF MINES AND GEOLOGY
BY lEA A. WItXIAMS

(Abstract)

While California on the south and Washington on the north have been for
years spending considerable amounts of money in the investigation of their
mineral resources, Oregon, as a State, has, until the present year, Invested
but $2,000 in a study of its mineral resources. The 1913 Legislature formally
(;stabllshed the Oregon Bureau of Mines and Geology and provided an appro
l»riation of $4D,0000 for carrying on its work for two years. According to the
act creating the Bureau, its duties cover a study of all of the geological re-
sources of the State and the publication of reports relating to these resources.
It is e.xpected also to conduit studies of the geological formations of Oregon.

In the past year four parties liave Iteeii in the held among the mining sec-
tions of the State. Investigations of the ceramic materials and of the building

138 PROCEEDINGS OF THE CORDILLERAN SECTION

stones are also under way. A large scale relief map of Oregon is being con-
structed, and a treatise covering the scattered geological data concerning
Oregon is also in preparation.

The laboratory equipment in all departments of the State University and
of the Oregon Agricultural College have been made available for the use of
the Bureau by the authorities of these two institutions.

Aside from the regular work outlined, a number of special problems have
been presented to the Bureau. Assistance has been rendered a large mining
( ompany in working out some of its metallurgical problems. About three
months' time was spent by a representative of the Bureau at the plant of this
company. Through the Bureau an anthracite coal project, which proved to
be based on a heavy deposit of black volcanic glass and in which several
thousand dollars had been invested, was finally cleared up. An investigation
of the possibility of using an acid volcanic tuff in the manufacture of Portland
cement at a point in ea.stern Oregon also promises to afford some valuable
results.

Presentetl froiii manuscript.

Discussion

Profes.sor Hitchcock explained the State Survey methods in the New Eng-
land States, especially in New Hampshire. Doctor Branner discussed the
organization of the Geological Survey of Brazil and the plans of the new
Oregon Bureau.

ROLE OF SEDIMENTATION IN DIA8TR0PHI8M AND VULCANI8M

BY F, M. HANDY

Read from manuscript^, in absence of author, by H. C. Culver.

The section adjourned at 2.50 in view of the meeting of the Seismolog-:
ical Society, which was to be held at 3.

The annual dinner, held in conjunction with the Paleontological and
Seismological Societies and under the auspices of the Le Conte Geological
Club, was held Friday evening, at 7 p. m., at the Faculty Club of the
University of Washington. After the dinner the following paper was
presented :

BASIN RANOE FAULTING IN THE NORTHWESTERN PART OF THE GREAT

BASIN

BY QEOBGE D. I.OUDERBACK

(Abstract)

The major and certain minor ranges from the Sierra Nevada to the Humboldt
were discussed and stratigraphic evidence was presented which indicates that

ABSTEACTS OF PAPERS 139

the faulting which was the prime agent in producing the present scarps oc-
curred in late Geological time, probably Pliocene or early Pleistocene. It was
further pointed out that this was the prevailing type of origin of the present
ranges throughout this and adjacent areas. Physiographic evidence also serves
to indicate that the present mountain fronts were generated by a continuous
series of elevations, and that it is improbable that they were produced by two
or more widely separated uplifts, with long periods of rest between.

The forms of the scarps were discussed and terracing of the scarps shown,
in such cases as were examiued, to be due to step faulting. The indications
are that these scarps have not suffered great denudation, and that the upper
portions have not migrated far back from their original positions. In a num-
ber of important occurrences cited there has been practically no recession of
the base.

The evidence at hand indicates that the faulting was in general essentially
normal faulting, and it was pointed out that the occurrence of occasional
thrusts ill a large area of normal faults or the passage of normal faults into
flexures is to be expected. Flexures and occasional thrusts do uot necessarily
mean general compression action, and the idea of deformatiou with expansion
is accepted as the best interpretation of the phenomena of the northwestern
Basin region.

An extension of the results to certain other parts of the Great Basin region
was also made.

Presented without notes and illustrated by maps, lantern slides, and
blackboard diagrams.

Discussion by Branner, Merriam, Lawson, and Weaver.

At the conclusion of this paper the section adjourned sine die.

140 proceedings op the cordilleran section

Eegister of the Seattle Meeting

FELLOWS

John C. Branner Andrew C. Lawson

G. Montague Butler George D. Louderback

Arthur J. Collier John C. Merriam

C. H. Hitchcock Charles E. Weaver

Henry Landes Ira A. Williams

Visitors and other geologists taking part in the meeting were :

J. H. Bretz Joseph Daniels

A. C. Culver Milnor Roberts

E. J. Saunders

There were also present a number of students and other visitors.
Altogether the attendance was as follows : Thursday morning session, 33 ;
Thursday afternoon, 18; Friday morning, 40; Friday afternoon, 14.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA
Vol. 26, pp. 141-170 March 31, 1915

PROCEEDINGS OP THE SIXTH ANNUAL MEETING OF THE
PAI.EONTOLOGICAL SOCIETY, HELD AT PHILADEL-
PHIA, PENNSYLVANIA, DECEMBER 29, 30, AND 31, 1914.

R. S. Bassler, Secretarij

CONTENTS

Page

Session of Tuesday, December 29 144

Report of the Council 144

Secretary's report 14ri

Treasui'er's report 145

Appointment of Auditing Committee 146

Election of officers and members 146

Election of new members 147

Ctiapter on paleontology of man 147

New business and announcements 147

Presentation of general papers 148

Occurrence of algal and bacterial deposits in the Aigonkian

Mountains of Montana ; by Charles D. Walcott 148

Fossil algse of the Ordovician iron ores of Wabana, Newfound-
land ; by Gilbert Van Ingen 148

Migration and succession of human types of the Old Stone Age

of Europe ; by Henry F. Osborn 149

Restorations of Pithecanthropus and Piltdown and Neanderthal

man ; by J. H. McGregor 149

Evidence proving that the Belly River beds of Alberta are equiv-
alent to the Judith River beds of Dog Creek and Cow Island,

Montana [abstract] ; by Charles H. Sternberg 149

Session of Wednesday, December 30 150

Completion of papers of general interest 150

Shawangunk formation of Medina age [abstract] ; by Charles

Schucliert 150

Pic d'Aurore section ; by John M. Clarke 150

Peccaries of the Pleistocene of New York; by John M. Clarke

and W. D. Matthew 150

Symposium on the passage from the Jurassic to the Cretaceous 151

Introduction ; by Henry Fairfield Osborn 151

The Morrison; an initial Cretaceous formation; by Willis T. Lee. 151

(Jeologic exposure of the Morrison ; by Charles C. Mook 151

SauroiMKlu and Stegosauria of the Morrison compared with that
of South Anu'iic a. England, and eastern Africa ; by Richard S.

Lull 151

a4i)

142 PROCEEDINGS OF THE PALEOKTOLOGICAL SOCIETY

Page

The paleobotanic evidence ; by Edward W. Berry 151

The invertebrate fauna of the Morrison; b.v T. W. Stanton 151

The addition and evolution of "characters" in paleontologic phyla ;

Presidential address by Henry Fairfield (Jsborn 151

Section of Vertebrate Paleontology 151

Megalocnus and other Cuban ground-sloths |iibstrai-t| : by Cjirlos
de la Torre and W. D. Matthew 15U

Affinities of Hyopsodus [abstract] ; by W. D. Matthew 152

New evidence of the affinities of the Multituberculata labstract] :
by Walter Granger 152

Heads and tails; a few notes relating to sauropod dinosanrs
[abstract] ; by W. J. Holland 153

Obsei'vations on Adapidte and other Leiuuroidea ; by W. K.

(Gregory 153

• Observations on the phylogeny of the higher Pi'imates [ali-
stract] ; by W. K. (iregory 153

Reconstruction of the skeleton of Brachiosaurus [abstrjict] ; t>y
W. D. Matthew 153

Fish fauna of the Conodont bed (basal Genesee) at Eighteen-
mile Creek, New York; by L. Hussakof and W. L. Bryant 154

Stratigraphic relations of the fossil vertebrate localities of Flor-
ida [abstract] ; by E. H. Sellai-ds 154

Scaled Amphibia of the Coal Measures ; by Roy L. Moodie 154

Section of invertebrate, paleobotanic, and general paleontology 154

Alexandrian rocks of northern Illinois and eastern Wisconsin ;
by T. E. Savage 155

Diastrophic importance of the unconformity at the base of the
Berea sandstone in Ohio ; by H. P. Cushing 155

Kinderhookian age of the Chattanoogan series ; by E. O. Ulrich . . 155
Session ot Thursday, December 31 .... .* 155

Devonian of central Missouri ; by E. B. Branson and D. K. Gregor. 15G

Olentangy shale of central Ohio and its stratigraphic signiticance
[abstract] ; by A. W. Grabau 156

Geological reconnaissance of Porto Rico ; by Charles P. Berkey . . 156

Relations of Cretaceous formations to the Rocky Mountains in
Colorado and New Mexico ; by Willis T. Lee 156

Evolution of the Anthozoa and the systematic position of Paleo-
zoic corals [abstract] ; by T. C. Brown 157

New facts bearing on the Paleozoic stratigraphy of the region
about Three Forks, Montana [abstract]; by W. P. Haynes 157

Studies of the morphology and histology of the Trepostomata
(Mouticuliporoids) [abstract] ; by E. K. Cuuiings ;ind ,1. J. Gallo-
way 158

Hamilton group of New York [abstract] ; by A. W. Grabau 158

A classification of aqueous habitats [abstract] ; by Marjorie
O'Connell 159

New .species of Ficus from the interglacial deposits of the Koote-
nay Valley, British Columbia [abstract]; by Arthur Hollick... 159

CONTENTS 143

Page
Rejrister of the Pliiladelpliin mectiiii;. 1014 160

Officers, correspondents, and members of the Paleontological Society 160

Minutes of the flftli annual meeting of the Pacific Coast Section of tlie

Paleontological Society ; C. A. Waring, Secretary 16<)

Election of officers 166

Papers of the Stanford meeting 166

Note on the Cretaceous Echinoderms of California ; by W. S. W.
Kew 166

Kelations of tlic Santa Margarita formation in the Coalinga East
Side Field [abstract] : l)y John H. llu(,'kman 166

Tentative correlation tabic of tlic Neocene of California ; 1)\
Bruce L. Clark 167

Fauna of the rx)wer Monterey of Contra Costa County, Califor-
nia ; l)y Bruce L. Clark 167

Extinct toad from Rancho La Brea [abstract] ; by Charles L.
Camp 167

Rodents of Rancho La Brca [ai)stract] ; by Lee R. Dice 167

Occurrence of mammal remains in the asphalt beds of McKit-
trick. California [abstract]; liy Neill C. Cornwall 167

Outline of the history of the Castoridfe [abstract] ; by W. P.
Taylor 167

('retaceous-Eocene contact in the Atlantic and Gulf Coastal Plain
I abstract] ; by L. W. Stephenson 168

lone formation of the Sierra Nevada foothills, a local facies of
the TIppei- Tejon-Eocene [abstract]; by Roy E. Dickerson 168

Sti-atigrapliic and faunal relations of the later Eocene of the
Pacific [abstract] : by Harold Hannibal 168

Fauna and relations of the white shales of the Coalinga District;
by John H. Ruckman 168

A'ertebrate fauna in the marine Tertiary of California; their sig-
nificance in determining the age of California Tertiary forma-
tions ; by J. C. Merriam 168

Geology of a portion of the McKittrick oil field; by G. C. Gester. . 16!l
Papers of the University of Washington meeting 161)

Sti-atigraphic and faunal relations of the Lincoln roiuialinii in
Washington ; by Charles E. Weaver 160

Cretaceous faunas of the Santa Ana Mountains [alistract] ; by
Earl L. Packai-d 16n

I{«'\ iew of the fauna of the Rattlesnake Pliocene of eastern Ore-
gon [al>stiact] ; by John C. Merriam 160

Eocene of the Cowlitz Valley : hy Charles E. Weaver 160

I"\iuna of the f^ipliomilia suttrrrnsis /one in the Roselnn-g quad-
rangle. Oregon [abstract] ; by Roy E. Dickerson 160

Evolution of tlic I'acific Coast Mactriche [abstract]; by Earl Ti.
Packard 170

Correlation of the Tertiary formations in western Wasliington :
b\ Chailrs 1]. WcaMT 170

144 proceedings of the paleoktological society

Session of Tuesday, December 29

President Henry Fairfield Osboru called the general session of the
Society to order at 2 o'clock, December 29, in the library of the Phila-
delphia Academy of Sciences. After some introductory remarks by the
President, the business session of the Society was opened with the read-
ing of the report of tlie Council by the Secretary.

REPORT OF THE COUNCIL

To the PaJconfoJngiral Society in Sixth Annual Meeting assemhhrl:

The first meeting of this year's Council was held at Princeton, New
Jersey, January 1, 1914, immediately following the adjournment of the
Society on that day. Pontine business, such as the suggestion of a ticket
for the following year and the consideration of new nominations for mem-
bership, was considered then ; but since this meeting all business of the
Society has been arranged by correspondence. A resume of administra-
tion for the Society's sixth year is presented in the following reports of
officers.

Secretary's Report

To the Council of the Paleontological Society:

Meetings. — The proceedings of the fifth annual meeting of the Society,
held at Princeton, New Jersey, December 31, 1913, and JaniiaiT 1; 1914,
have been published in volume 25, pages 127-156, of the Bulletin of the
(xeological Society of America and distributed to the members in March,
1 914. Besides this publication, the scientific papers of the Society printed
and distributed during the year occupy all of number 3 of volume 25,
Bulletin of the Geological Society of America, consisting of twelve
articles, totaling 170 pages.

The Council's proposed nomination for officers and announcement that
the sixth annual meeting of tlie Society would occur at Philadelphia,
Pennsylvania, at the invitation of the local members, were forwarded to
the members on March 10, 1914.

Membership. — During the year the Society has lost by death two of
its members — Dr. Theodore M. Gill, of the Smithsonian Institution, who,
although interested in paleontology, was best known for his researches on
recent animals, particularly fish, and Dr. J. C. Hawver, educator and
scientist, of Auburn, California, whose name will always be associated
with the celebrated Hawvor Cave of El Dorado County, California.

One resignation has occurred during the year and two members have
been dropped for non-payment of dues. The 11 candidates elected at

REPORT OF THE COUNCIL 145

the fifth annual meeting have been placed on the rolls, making the present
enrolment 158. Ten candidates are under consideration for election to
membership at the present meeting, so that the steady growth of the
Society is being maintained.

At this year's election for Fellows of the Geological Society of America,
Messrs. E. C. Jeffrey and T. Poole Maynard, of the Paleontological So-
ciety, were elected to Fellowship.

Pacific Coast Section. — The fifth annual meeting of the Pacific Coast
Section of the Society was held at Stanford University, commencing
Friday, April 84, 1914. Fifteen papers, dealing mainly with Vertebrate
Paleontology of the West Coast, were read at this meeting. The minutes
of the section are printed, pages — to — of this Bulletin.

Respectfully submitted, R. S. Bassler,

Secretary.

Washington, D. C, December 28, 1914.

Treasurer's Report

To the Council of the Paleontological Society:

The Treasurer begs to submit the following report of the finances of
the Society for the fiscal year ending December 24, 1914:

RECEIPTS

Cash on hand December 24, 1913 $227.83

Dues from 64 members 192 . 10

$419.9.3

EXPENDITURES

Treasurer's office :

Postage $3 . 66

Printing and stationery .34

$4.00

Secretary's offiee :

Secretary's allowance $!')0 . 00

Expen.ses 39.05

89.05

Geological Society of America :

Share of expenses, Princeton meeting $10.10

Separates 38.60

48.70

Pacific Coast Section :

Secretary's exi)oiises $18.20 18.20

$l.'i9.95

Balance on hand Deceral)er '24. 191 1 259. 9S

1^419.93

146 PROCEEDINGS OF THE PALEOKTOLOGICAL SOCIETY

Net increase in funds $32 . 15

Outstanding dues 51 . 00

Respectfully submitted, Richard Swann Lull,

Treasurer.
New Haven, Coxnectic;ut, December 34, 1914.

APPOINTMENT OF AUDITING COMMITTEE

Tlip appointment of a committee to audit the Treasurer's accounts was
next in order and the President selected II. F. Cleland and C. R.. East-
man.

ELECTION OF OFFICERS AND MEMBERS

The results, of the ballot for officers for 193 5 and election of members
was the next matter of business and was announced by the Secretary as
follows :

OFFICERS FOR 1915

President:
Edward 0. Uleich, Washington, T). C.

First Vice-President:
J. C. Merriam, Berkeley, Cal.

Second Vice-President :
Gilbert Van Ingen, Princeion, N. J.

Third Vice-President:
F. II. Knowlton, Washington, D. C.

Secretary:
R. 8. l)A,s,sj>i;i;. W'ashinglon, i). C.

Treasurer:
Richard S. Lull, Xew Haven, Conn.

Editor:
Charles R. Eastman, New York City

MEMBERS

Junius Henderson, University of Colorado, Boulder, Colo.
Charles C. Mock, American Museum of Natural History, New York City.
Charles E. Resser, U. S. National Museum, Washington, D. C.
Merton Y. Williams, Geological Survey of Canada, Ottawa, Canada.
Alice E. Wilson, Victoria Memorial Museum, Ottawa, Canada.

NEW MEMBERS 147

ELECTION OF NEW MEMBERS

The President then called the attention of the Society to five nomina-
tions for membership which had been received and indorsed by the Coun-
cil too late to be placed on this year's printed ballots. The names and a
brief statement regarding these proposed members follow.

Albert L. Barrows (M. S., University of California, 1912), Instructor in
Department of Zoology, University of California, Berlieley, Cal. Engaged
in invertebrate paleontology. Proposed by J. C. Merriam and F. M.
Anderson.

John A. Guintyllo, Assistant in paleontology. University of California. Pro-
posed by J. C. Merriam and F. M. Anderson.

WiNTHROP P. Haynes (Ph. D., Harvard, 1914), Instructor in Geology, Welles-
ley College, Wellesley, Massachusetts. Engaged in stratigraphic paleon-
tology. Proposed by P. E. Raymond and H. W. Shimer.

Clarence L. Moody, Student of paleontology. University of California. En-
gaged in invertebrate paleontology. Proposed by J. C. Merriam and F. M.
Anderson,

Jorgen O. Nomland (B. S., University of North Dakot.M, 1010), Graduate Stu-
dent, University of California. Engaged in invprtebrate paleontology.
Proposed by J. C. Merriam and F. M. Anderson.

In the discussion that followed the motion to suspend the by-laws in
order to elect these members at the present meeting, John M. Clarke
asked that the name of Winifred Goldring (M. A., Wellesley College,
1913), assistant in paleontology, New York State Museum, proposed by
John M. Clarke and A. W. Grabau, be added to the list. On motion, it
was then voted by all members present that these six nominees be elected
to membership in the Society.

CHAPTER ON PALEONTOLOGY OF MAN

At the fifth annual meeting the proposition to organize a chapter deal-
ing with the paleontology of man was discussed, but action was deferred
and the matter was referred back to the Council. After further consid-
eration, the Council reports that it seems inadvisable to organize such a
chapter, because papers dealing with this subject are of general interest
to all of the members and should be presented before the Society in gen-
eral session.

NEW BUSINESS AND ANNOUNCEMBNTS

President Osbnrn then road a comnmnicalion fnun .1. ( '. Merriam. who,
by previous vote of the Council, had been placed in iliarge of arrange-
ments for the meeting of the Paloontological Society to be held in Cali-

XI— Bull. Gkol. Soc. Am., Vol. 20. 1014

148 PROCEEDIKGS OF THE PALEOJS'TOLOGICAL SOCIETY

fornia in August, 1915. Professor Merriam reported that this meeting
bad been arranged for the first week in August, and that the sessions
would occur as follows : The first session will be at the University of
California on August 3, the second at Stanford University on August 4,
and the remaining sessions at the University of California. Feeling that
the most important features of the program should relate to matters of
mutual interest to the members of the East and of the extreme West, and
coDsidering further that material of the Pacific area might be of especial
interest to those visiting California, the Pacific Coast members have ar-
ranged for a series of papers on correlation between the paleontologic
record of the far West and the standard records of the better known
portions of the earth's surface. This series will include a general dis-
cussion of paleontologic criteria used in determining time relations be-
tween stratigraphic units and several symposia on correlation between
the West and other parts of the world.

After some general announcements by the President as to arrangements
for the several sectional meetings, and there being no further matters of
business, the Society proceeded to the reading of papers of general in-
terest.

PRESENTATIOX OF GENERAL PAPERS

The first paper of this section, which was presented by the author and
illustrated with lantern slides and specimens, brought forth a general
discussion of the problem, in which C. A. Davis, Charles Schuchert, E. 0.
Ulrich, G. R. Wielaurl, and the author took a prominent part; 15
minutes.

OCCURRENCE OF ALGAL AND BACTERIAL DEPOSITS IN THE ALGONKIAN

MOUNTAINS OF MONTANA

BY CHARLES D. WALCOTT

Another paper on fossil algfe was selected for presentation next and
was illustrated by the author with lantern slides ; 30 minutes.

FOSSIL ALO^ OF THE ORDOVICIAN IRON ORES OF WABANA, NEWFOUNDLAND

BY GILBERT VAN INGEN

Two papers on the paleontology of man were next in order. The first
was presented by the author and was illustrated by lantern slides; 15
minutes.

ABSTRACTS OF PAPERS 149

MIGRATION AND SUCCE8ISI0N OF HUMAN TYPES OF THE OLD STONE AGE OF

EUROPE

BY HENRY FAIRFIELD OSBORN

Following President Osborn's paper and supplementing it was a dem-
onstration of models of ancient man, which was further illustrated with
lantern slides; 15 minutes.

RESTORATIONS OF PITHECANTHROPUS AND PILTDOWN AND NEANDERTHAL

MAN

BY J. H. MC GREGOR

The above two papers brought forth a discussion in which J. M. Clarke
and the two authors took part.

There was next read from manuscript by the author and illustrated
with lantern slides and panoramic views a paper of general interest on
account of its bearing on Upper Cretaceous stratigraphy.

EVIDENCE PROVING THAT THE BELLY RIVER BEDS OF ALBERTA ARE
EQUIVALENT TO THE JUDITH RIVER REDS OF DOG CREEK AND
COW ISLAND, MONTANA

BY CHARLES H. STERNBERG

iA1)stract)

This paper will be illustrated with lantern .slides and several photographs,
including a panoramic view of Dog Creek, showing tlie three distinct horizons
of the Eagle sandstone, Clagett shales, and Judith River beds. The slides
show the Bear Paw shales on top of the Judith River beds at the head of an
eastern branch of Dog Creek called Taffy Creek. In the Bear Paw shales were
secured Fort Pierre Ammonites, Baculites, a new Clidastes, and bones of ple-
siosaurs. Immediately below, in the Judith River beds, we found a typical
locality for the vertebrates and made a large collection of Dinosaur, Myleda-
phus teeth, and vertebrae of Campsosaurus and the footed ischium of Lambe's
Stephanosaurus and other Belly River vertebrates. We found Myledaphus
teeth in the Eagle sandstones, leaves belonging to Belly River types, as well
as numerous shells from the .same horizon. We followed the strata down to
Cow Island and found the stratigraphy simple, but for the uplift of the strata,
everj^where. My work there substantiated Hatcher and Stanton in every par-
ticular, as noted in their bulletin of the U. S. Geological Survey.

At 5 o'clock the Society adjourned for the day. In the evening the
members assembled to hear the address of the retiring President of the
Geological Society of America, and attended the iiomplimentary smoker
following this address.

150 PROf'EEDINGS OF THE PALEONTOLOGICAL SOCIETY

Session or Wednesday, December 30

Wednesday morning, at 9.30, the Society was called to order by Presi-
dent Osborn, who asked for the report of the Auditing Committee as the
first matter of business. The committee reported that the accounts of
the Treasurer were found to be correct ; whereupon it was voted that their
report be accepted. The chairman next announced that as the sym-
posium, in joint session Avith the Geological Society of America, would
commence at 10.30, the intervening time would be devoted to papers of
general interest.

completion of papers of general interest

The first paper of the morning was then presented by the author and
illustrated by lantern slides; 15 minutes. Discussed by J. M. Clarke,
A. W. Grabau, and C. J. Sarle. with replies by the author.

SRAWANGUNK FORMATION OF MEDINA AGE
BY CHARLES SCHUCHERT

(Abstract)

The Shawangunk has furnished Arthrophycus harlani (A. alleohamoise)
and eurypterids. The formation will be traced from Kingston, New York, to
Lewiston, Pennsylvania.

The next paper was transferred to the Paleontological Society from
the program of the Geological Society of America and was illustrated
by the author with a large drawing shoAving this splendid section in the
colors of the rocks themselves; 10 minutes. Discussed by Charles Schu-
chert.

PIC D'AURORE SECTION
BY JOHN M. CLARKE

Announcement of an interesting discussion of vertebrate remains in
the Pleistocene of New York was then made by the senior author under
the following title :

PECCARIES OF THE PLEISTOCENE OF NEW YORK
BY JOHN M. CLARKE AND W. D. MATTHEW

The hour for the symposium having arrived, the Society adjourned
to the general lecture hall of the Philadelphia Academy of Sciences,

ABSTRACTS OF PAPERS 151

meeting in joint session with the Geological Society of America. The
speakers and titles of their special subjects in the symposium are as
follows :

SYMPOSIUM 0\^ THE PASSAGE PROM THE JURASSIC TO THE CRETACEOUS

INTRODUCTION
BY HENRY FAIRFIELD OSBORN

THE MORRISON; AN INITIAL CRETACEOUS FORMATION
BY WILLIS T. LEE

GEOLOGIC EXPOSURES OF THE MORRISON
BY CHARLES C. MOCK

8AUR0P0DA AND 8TEG0SAURIA OF THE MORRISON COMPARED WITH THAT
OF SOUTH AMERICA, ENGLAND, AND EASTERN AFRICA

BY RICHARD S. LULL

THE PALEOBOTANIC EVIDENCE
BY EDWARD W. BERRY

THE INVERTEBRATE FAUNA OF THE MORRISON
BY T. W. STANTON

With the completion of the symposium, at 1 p. m., the Society ad-
journed for luncheon, meeting again in general session at 3.30 in the
library. There was then presented the presidential address of the retir-
ing President, on the subject,

THE ADDITION AND EVOLUTION OP "CHARACTERS" IN PALEONTOLOGIC

PHYLA

BY HENRY FAIRFIELD OSBORN

Following this address, which was illustrated by lantern slides, Presi-
dent Osborn announced that the Society would then meet in two sections
for the rest of the program, a vertebrate section to occupy an adjoining
room and a section of invertebrate, paleobotanic, and general paleontology
to remain in session in the library. The minutes of the first section
follow.

SECTION OF VERTEBRATE PALE()N'l'OLO<iY

The section was called to order by l^resideiit Osborn, cliairman, at
13.35, Wednesday afternoon, for the reading of sectioiial papers. W. D.

152 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

Matthew was requested by the chair to act as secretary. The following
papers were submitted :

MEOALOCNUS AND OTHER CUBAN OROUND-SLOTHS
BY CARLOS DE LA TORRE AND W. D. MATTHEW

(Abstract)

Four genera of ground-sloths are represented in the Cuban Pleistocene col-
lections made by La Torre, Brown, and Moreno. The largest and most abun-
dant is Megalocnus Leidy, of which the complete skeleton has been articulated
and mounted. The other genera, Mesoonus. Miocnus, and Microcnus, are
smaller animals, the last no larger than a woodchuck. Although well distin-
guished, they form a related group, their nearest continental allies being
Megalonyx of Pleistocene North America and Euehotocops of Miocene South
America. Affinities to the modern tree-sloth Choluepus are not to be excluded
for the smaller genera.

AFFINITIES OF HY0P80DU8
BY W. D. MATTHEW

(Abstract)

Jaws of Hyopsodus are very common in the Eocene, but skulls and skeleton
parts are rare. The zoological position of this small mammal has been much
questioned. It has been referred by different authors to the Suillines, to the
Primates, to the Insectivora. Evidence is now brought forward for its refer-
ence to the order Coudylarthra.

NEW EVIDENCE OP THE AFFINITIES OF THE MULTITUBERCVLATA

BY WALTER GRANGER

(Abst7-act)

These Mesozoic and early Tertiary mammals have been regarded by some
authorities as Marsupials, by others as Monotremes. Additional and more
complete skeleton material from the Paleocene of New Mexico indicates that
they are not nearly related to either, but are probably entitled to rank as a
distinct primary division of the Mammalia, equivalent in evolutionary stage
to the Marsupials, but not closely related, and more remote from either Mono-
tremes or Placentals.

The paper was discussed by Messrs. Gidley, Gregory, Osborn, and
Matthew.

The meeting then adjourned.

ABSTRACTS OF PAPERS 153

The section reconvened at 9.10 a. m., Thursday, January 31, and the
program of sectional papers was continued as follows :

HEADS AXD TAILS; A FEW NOTES RELATING TO SAUHOPOD DINOSAURS

BY W. J. HOLLAND

(Abstract)

The author aimounced the discovery of many dinosaur skeletons, some re-
markably complete, iu the quarries worked by the Carnegie Museum In the
Morrison formation of Uiiita County, Utah. He presented the evidence for
associating vpith the skeleton of Brontosaurus a skull unlike that arbitrarily
referred to this genus by Professor Marsh, and much more nearly resembling
the skull of Diploducus. The tail of Brontosuurus is extended in a long,
slender whiplash, as in Diplodocus.

llie papoi- was discussed by Messrs. Osborn, Lull, Granger, and
Matthew.

Mr. Granger's paper, submitted at the preceding session, was then
brought up for further discussion by Professor Osborn, Doctor Matthew,
and Mr. Granger.

The next two papers read were:

OBSERVATIONS ON ADAPID^E AND OTHER LEMUROIDEA
BY W. K. GREGORY

OBSERVATIONS ON THE PH7L00ENY OF THE HIGHER PRIMATES

BY W. K. GEEGORY

(Abstract)

The author presented certain conclusions from recent researches on living
and extinct primates, with the aid of more complete materials than had hith-
erto been available. The importance of the basicranial characters and their
interpretation were discussed and present conclusions stated as to the affini-
ties of the several living and extinct groups.

The papei's were discussed by Professor Osborn and Doctor Matthew.

RECONSTRUCTION OF THE SKELETON OF BRACHIOSAURUS

BY W. D. MATTHEW

(Abstract)

Tiio author presented a sketch reconstruction of the skeleton of tliis genus,
tlie largest known lUnosaui', based on the skeletons iu the Field Miiseum,
Chicago, described by E. S. Itiggs, and partial descriptions by Professors
Branca and Janensch of the skeleton from German East Africa in the Berlin
Museum.

154 PROCEEDI^^GS OF THE PALEONTOLOGICAL SOCIETY

FISH FAUNA OF THE GONODONT BED (BASAL GENESEE) AT EIGHTEEN-MILE

CREEK, NEW YORK

BY fv. HUSSAKOF AND W. L. BRYANT

(Ahstract)

The conodont bed is a thin layer of imimre limestoue at the base of the
Genesee at Eighteen-mile Creek, New York. Tt has a maximum thickness of
four or five inches, thins out in either direction, and in some sections is absent
altogether. It thus seems to occur in lenticular patches. Conodonts are ex-
tremely abundant in it, to which circumstance is due its name.

Until a few years ago no vertebrate remains were known to occur in this
bed ; but an extensive and very remarkable fish fauna has since been obtained.
This includes sharks, Arthrodires, Ptyctodonts, Ichthyodorulites, Dipnoans,
and Ganoids. There are four or five new genera and about a d(jzen new spe-
cies in the materials. The remains are generally fragmeutal, but complete
dental elements and other plates have been collected. The assemblage consti-
tutes one of the most remarkable Devonic fish faunas known. It will be de-
scribed and fully illustrated by the authors in a catalogue of the fossil fishes
in the Museum of the Buffalo Society of Natural Science, now nearly ready
for press.

Discussion by Messrs. Wieland and Burnett Smith.

8TRATIGRAPHIC RELATIONS OF THE FOSSIL VERTEBRATE LOCALITIES OF

FLORIDA

BY E. H. SELLARDS

(Ahstract)

Two principal faunal horizons were considered, the Alachua clays and the
Peace Creek beds. The latter have been thought to be intercalated between
marine Pliocene strata, but the evidence for this is inconclusive, and there
appears to be no reason against regarding the fauna as Pleistocene. The
Alachua clays are probably Upper Miocene,

The paper was discussed by Messrs. Osborn, Gidley, and Matthew.

SCALED AMBHIBIA OF THE COAL MEASURES
BY ROY L. MOODEE

Tlie paper was presented and briefly discussed by Doctor Grregory.
This being the last paper on the program, the section then adjourned.

SECTION OF INVERTEBRATE, PALEOBOTANIC, AND GENERAL PALEONTOLOGY

This section was called to order for its first session at 3.30, Wednesday
afternoon, wit^i Vice-President Van Tngen presiding. The chairman

TITLES OF PAPERS 155

announced that, on account of a conflict in the program, the papers of
Group B of the Geological Society of America had been transferred to
the Paleontological Society for reading.

The first paper of Group B was presented by the author and illustrated
by lantern slides; 10 minutes. Discussed by E. 0. Ulrich and A. W.
Grabau, with replies by the author.

ALEXANDRIAN ROCKS OF NORTHEASTERN ILLINOIS AND EASTERN

WISCONSIN

BY T. E. SAVAGE

There was next presented by the author, illustrated by diagrams and
lantern slides, a paper transferred from Group A of the Geological
Society of America to tlie Paleontological Society in order that all
papers bearing on the black shale problem should be read in succession.
The discussion on this paper was postponed until all of those dealing
with the subject had been read.

DIASTROPHIC IMPORTANCE OF THE UNCONFORMITY AT THE BASE OF THE

BEREA SANDSTONE IN OHIO

BY H. P. GUSHING

The second paper in the black shale discussion was read by the author
and illustrated by drawings; 30 minutes.

KINDERHOOKIAN AGE OF THE CHATTANOOGAN SERIES

BY E. O. ULRICH

At 5.30 the Society adjourned for the day. Wednesday evening the
members attended the annual dinner with the Fellows of the Geological
Society of America at the Hotel Walton.

Session of Thursday, December 31

Thursday morning the section met at 9, with Ibe com])letiiin of the
black shale and related papers first on the pi-ograni. Vice-President Van
Tngen presided.

Tile first paper was presented by the senior aullior and was illustrated
by di'awings; 10 minutes.

156 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

DEVONIAN OF CENTRAL MISSOURI
BY E. B. BRANSON AND D. K. GKEGOB

Next was presented by the autlior, illustrated by diagram, the foliuw-
iug paper of the Paleontological Society's program ; 30 minutes.

OLENTANOY SHALE OF CENTRAL OHIO AND ITS STRATIORAPHIC

SIGNIFICANCE

BY A. W. GBABAU

(Abstract)

lu its typical localities the Olentaugy shale is intimately associated with the
Hurou shale, this latter represeiitiug merely a change in faoies, without inter-
ruption of stray graphic continuity. The Olentaugy clearly belongs to the
Upper Devonic, resting discouformably on limestones of Lower Hamilton age.
The shales and limestones now classed as Olentaugy in northern Ohio are.
however, early Hamilton, and considerably older than the Olentaugy. This
name should therefore not be used for strata of Hamilton age, but instead the
name Prout series is proposed for the northern Ohio deposits of Hamilton age.

This concluded the series of black shale papers and a general discus-
sion followed, in which Messrs. Branson, Gushing, Foerste, Grabau,
Kindle, Prosser, Savage, Schuchert, David White, I. C. White, and M. Y.
Williams took part.

There was then presented by the author a stratigraphic paper, illus-
trated by lantern slides and diagrams; 30 minutes. Discussed by Charles
Schuchert and Gilbert Van Ingen.

GEOLOOICAL RECONNAISSANCE OF PORTO RICO
BY CHASLES P. BEBKEY

The last paper of Group B was presented by the author and illustrated
by lantern slides ; 15 minutes.

RELATIONS OF CRETACEOUS FORMATIONS TO THE ROCKY MOUNTAINS IN

COLORADO AND NEW MEXICO

BY WILLIS T. T.F.R

By previous arrangement the two sections of the Society met in gen-
eral session at 12.30, when matters of business relating to the next meet-
ing place, etcetera, were discussed.

In closing the session, the splendid arrangements to make the Society's
Philadelphia meeting a pleasant one were also discussed, and the Secre-

ABSTRACTS OF PAPERS 157

tary was authorized to convey the Society's appreciation to the members
of the local committee.

At 1 o'clock the Society adjourned for luncheon, to meet again at 2
p. m. in two sections.

The first paper in the afternoon session of the section of invertebrate,
paleobotanic, and general paleontology was presented by the author and
illustrated by drawings; 15 minutes.

EVOLUTION OF THE ANTHOZOA AND THE SYSTEMATIC POSITION OF

PALEOZOIC CORALS

BY T. C. BKOWN

(Abstract)

lu the developuieut of the zooids of modern Anthozoa a stage is always
observed in whicLi there are eight mesenteries present. This condition may
persist throughout life, as, for example, in the subclass Alcyouaria ; or it may
be only transitory, as it is in the subclass Zoantharia.

To the subclass Alcyouaria probably belong those Paleozoic corals that are
either without septa or iu which the septa probably were not directly related
to the internal mesenteric structure of the zooid — Columnaria, Favosites.
Syringopora, etcetera.

In the subclass Zoantharia four distinct orders can be recognized, and these
orders are distinguished by the number and arrangement of the mesenteries
added beyond the primitive number eight. In the Cerianthidea new meseu-
teries are added at only one point in the periphery of the zooid ; in the
Zoanthidea they are added at two points ; in the Tetracorallidea at four points :
in the Actiniidea at many points; generally some multiple of six. The first
two of these orders are known only from modern forms; the third is confined
to the Paleozoic ; the fourth probably begins in the Mesozoic and is dominant
at the present time.

The second paper of the afternoon was given by the author and illus-
trated by lantern slides and diagrams; 15 minutes. Discussed by Charles
Schuchert, P. E. Raymond, J. M. Clarke, and A. W. Grabau.

NEW FACTS BEARING ON THE PALEOZOIC STRATIGRAPHY OF THE REGION

ABOUT TJlin:E FORKS, MONTANA

BY W, P. HAYNES

(Abstract)

Iu the various sections studied in the region about Three Forks and the
adjacent country to the south, in southwestern ^^ontana, the Jefferson lime
stone lies in apparent conformity on the Cambrian limestone, without any
intervening formations. From I'aleozoic evidence all of the Jefferson lime-
stone is regarded as of Devonian age, and it is considered to lie disconform-
ably on the Cambrian limestone iu this region.

158 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

The presence of intervening strata of different lithologieal character, con-
taining in some cases fossils of Ordovician and Silurian ages, between the
Cambrian limestone and the Jefferson limestone, as noted by various writers,
iu sections in neighboring regions to the west and southwest, points to a
stratigraphic overlap which involves a hiatus in sedimentary record for the
i-egion about Three Forks.

The Three Forks formation overlies the Jefferson limestone in this region,
but differs greatly in its lithologieal characters from north to south. In the
type region at Three Forks and to the north, along the Missouri River, it
consists of seven fairly distinct shale and limestone members, the upper five
of which are generally fossiliferous and contain a late Devonian faunule. In
the southern sections the formation is chiefly limestone and sparsely fossilif-
erous. The Three Forks formation is not nearly so widely distributed as the
Jefferson limestone or the overlying Madison limestone.

The next paper was given by the senior author and illustrated by lan-
tern slides; 20 minutes. Discussed by E. S. Bassler and E. E. Cumings.

STUDIES OF THE MORPHOLOOY AND HISTOLOGY OF THE TREP08T0MATA

(M0NTICULIP0R0ID8)

BY E. B. CUMINQS AND J. J. GAIXOWAY

(Abstract)

This paper is a minute study of wall structure, with reference to its
taXonomic significance; of the exact nature and function of aeanthopores in
the genus Dekayia; of certain peculiar cystlike structures in a number of
genera ; of communication pores iu numerous genera, and of the structure and
relationships of the recent sponge genus, Merlia.

Then followed a paper presented by the author, with diagram ; 30
minutes. Discussed by John M. Clarke, with reply by the author.

HAMILTON GROUP OF NEW YORK
BY A. W, GBABAU

(Abstract)

The various subdivisions originally made by the author for the Hamilton of
Eighteen-mile Creek have been correlated with a similar number of subdi-
visions in central New York by the New York Survey. The validity of this
correlation will be considered and the facts suggesting that an error has been
made will be given. A new series of names for these subdivisions will be
proposed. A brief comparison with the Traverse group of Michigan will be
made.

The next paper was read by the author; 15 minutes. Discussed by
C. J. Sarle, Charles Schuchert, J. M. Clarke, M. Y. Williams, Charles
Prosser, and Henry M. Ami.

ABSTRACTS OF PAPERS 159

A CLASSIFWATION OF AQUEOUS HABITATS
BY MARJORIE O'CONNELL

(Abstract)

All attempt will be made to classify aqueous habitats on the basis of
salinity. A table of salinity ranges for the various tyi)es will be given. \Aitli
a discussion and restriction of the terms fresh, brackish, and marine waters.
The faunal significance of these habitats will be considered and several illus-
trations given, with especial attention to the relation between salinit.v and
faunas. The purpose of the study is to obtain a faunal standard for each
habitat by which faunas of former periods can be judged and interpreted in
terms of habitat.

The final paper of the program was g-iven by the author, who illus-
trated it by drawings.

NEW SPECIES OF FICUS FROM THE INTEROLACIAL DEPOSITS OF THE
KOOTENAY VALLEY, BRITISH COLUMBIA

BY ARTHUR HOLLICK

{Ahstract)

Fossil plants, if their generic relationships to living plants can be satis-
factorily determined, are generally regarded as excellent climatic indices.
Remains of a species of Ficiis, for example, in strata of any geologic age would
at once be recognized as good evidence that a tropical or subtropical climate
must have prevailed in the locality where the strata are, at the time when
they were laid down. The generic identiflcationi of fossil leaves can not al-
ways be relied on as correct ; but well preserved remains of fruit are generally
very satisfactory subjects for determination, especially if the generic char-
acters are peculiar or striking. Recently a study was made of a collection of
fossil plants, stems, leaves, and fruit from interglacial deposits in the Kootenay
Valley, British Columbia, sent for examination and report by the Director of
the Canada Geological Survey.

At 4.30 p. 111. the Society adjourned.

160

PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

Heney M. Ami
Paul Bartsch
Ray S. Bassler
Edward \V. Berry
E. B. Branson
Barnum Broavn
Thomas C. Brown
William B. Clark
John M. Clarke
Herdman F, Cleland
Will E. Crane
Edgar R. Cumings
Charles R. Eastman
August F. Foerste
J. W. GinLEY
C. E. Gordon
Amadeus W. (tRABAU
Walter Granger
W. K. Gregory
Chris A, Hartnagel

WiNTHROP P. HaYNES

Arthur Hollick
l. hussakof
Edward M. Kindle
Frank H. Knowlton
Richard S. Lull
J. H. McGregor

W. D. Matthew
Charles C. Mook
Marjorie O'Connell
Henry F. Osborn
R. W. Pack
Charles S. Prosser
Percy E. Raymond
Chester A. Reeds
Thomas E. Savage
Charles Schuchert
William J. Sinclair
Burnett Smith
T. W. Stanton
L. W. Stephenson
Charles H. Sternberg
Charles K. Swartz
Mignon Talbot

E. L. Troxell

M. W. Twitchell
Edward 0. Ulrich
Gilbert Van Ingen

F. M. Van Tuyl

T. Wayland Vaughan
Charles D, Walcott
David White

G. R. Wieland
Merton Y. Williams

OFFICERS, CORRESPONDENTS, AND MEMBERS OF THE
PALEONTOLOGICAL SOCIETY

OFFICERS FOR 1915

President:
Edward O. TTlrioh, Washington, D. C.

First Vice-President:
J. C. Merhiam, Berkeley. California

Second Vice-President:
Gilbert Van Ingen, Princeton, New Jersey

Third Vice-President :
F. IT. Knowlton, Washington, D. C.

Secretary:
R. S. Bassler, Washington, D. C.

Treasurer:
Richard S. Lull, New Haven, Connecticut

Editor:
Charles R. Eastman. New York Citv

MEMBERSHIP, 1915
CORREFtPONDENTff

Dr. A. C. Nathorst, Royal Natural History Museum, Stockholm, Sweden.

S. S. BucKMAN, Esq., Westfield, Thame, England.

Prof. Charles DfePERET, University of Lyon, Lyon (Rhone), France.

Dr. Henry Woodward, British Museum (Natural History), London. England.

MEMBERS

Jos6 G. Aguilera, Institute Geologico de Mexico, City of Mexico, Mexico.

Truman H. Aldrich, care post-office, Birmingham, Ala.

Henry M. Ami, Geological and Natural History Survey of Canada. Ottawa,

Canada.
F. M. Anderson, 2604 Etna Street, Berkeley, Cal.
Robert Anderson, 7 Richmond Terrace, London, England.
Ralph Arnold, 021 Union Oil Building, Tx)s Angeles, Cal.
RuFUS M. Bagg, Jr., Lawrence College. Appleton, Wis.
Charles L. Baker, 71 fi Southern Pacific Building, Houston, Texas.

(161)

162 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

Erwin H. Barbour. University of Nebraslia, Lincoln, Nebr.

Paul Babtsch, U. S. National Museum, Washington, D. C.

Harvey Bassler, Geological Department, Johns Hopkins University, Balti-
more, Md.

Ray S. Bassler, U. S. National Museum, Washington, D. C.

Joshua W. Beede, Indiana University, Bloomington, Ind.

Walter A. Bell, 8 Prospect Place, New Haven, Conn.

B. A. Bensley, University of Toronto, Toronto, Canada.

Fritz Bkrckhemer, Department of Paleontology, Columbia University, New
York City.

Edward W. Berri% Johns Hopkins University, Baltimoi'e, Md.

Arthur B. Bibbins, Woman's College, Baltimore. Md.

Walter R. Billings, 1250 Bank Street, Ottawa, Canada.

Thomas A. Bostwick, 43 Livingston Street, New Haven, Conn.

R. B. Branson, University of Missouri, Columbia, Mo.

Barnum Brown, American Museum of Natural History, New York City.

Thomas C. Browx. Bryn Mawr College, Bryn Mawr, Pa.

William L. Bry'ant, Buffalo Society of Natural History, Buffalo, N. Y.

IjANCASTER D. Burling, Geological Survey of Canada, Ottawa, Canada.

Charles Butts, U. S. Geological Survey, Washington, D. C.

John P. Buwalda. 2m0 Ridge Ifoad. Berkeley, Cal.

Ermine C. Case, University of Michigan, Ann Arbor, Mich.

George H. Chadwick, University of Rochester, Rochester, N. Y.

Bruce L. Clarke, University of California, Berkeley, Cal.

William B. Clark, Johns Hopkins University, Baltimore, Md.

.ToHN JM. Clarke, Education Building, Albany, N. Y.

Herdman F. Cleland, Williams College, Williamstown, Mass.

Harold J. Cook, Agate, Nebr.

Will E. Crane, Swissvale post-office, Pittsburgh, Pa.

Edgar R. Cumings, Indiana University, Bloomington, Ind.

W. H. Dall. U. S. National Museum. Washington, D. C.

Bashford Dean, Columbia University, New York City.

Okville a. Derby. SO Rua do Rio Branco, Sao Paulo. Brazil.

RoY E. Dickerson, 1320 Fifth Avenue, San Francisco, Cal.

John T. Doneghy. Jr., 963 Yale Station, New Haven, Conn.

Earl Douglass. Carnegie Museum, Pittsburgh, Pa.

Charles R. Eastman, American Museum of Natural History, New York City.

George F. Eaton, 80 Sachem Street, New Haven, Conn.

John Eyerman, "Oakhurst," Easton, Pa.

August F. Foerste, 128 Rockwood Avenue. Dayton, Ohio.

Julia A. Gardner, Department of Geology, Johns Hopkins University, Balti-
more, Md.

G. S. Gester, 711 Flood Building. San Francisco, Cal.

Hugh Gibb, Peabody Museum. Yale University, New Haven, Conn.

J. W. Gidley, U. S. National Museum, Washington, D. C.

J. Z. Gilbert, Los Angeles High School, Los Angeles. Cal.

Clarence E. Gordon, Massachusetts Agricultural College. Amherst, Mass.

Charles N. Gould, 408 Terminal Building. Oklaiioma City. Okia.

Amadeus W. Grabau, Columbia University, New York City.

LIST OF MEMBERS 163

Walter Gbangeb, American Museum of Natural History, New Yorlj City.

F. C. Greene, U. S. Geological Survey, Washingtou, D. C.

W. K. Gregory, American Museum of Natural History, New York City.

Norman McD. Gkier, 399 Elm Street, New Haven, Conn.

Harold Hannibal, Stanford University, Stanford. Cal.

George W. Harper, 2139 Gilbert Avenue. Cincinnati, Ohio.

Gilbert D. Harris, Cornell University, Ithaca, N. Y.

Chris. A. Hartnagel. Education Building, Albany, N. Y.

Adam Hermann, American Museum of Natural History, New York City.

William J. Holland, Carnegie Museum, Pittsburgh, Pa.

Arthur Hollick, New York Botanical Garden, Bronx Park, New York City.

George H. Hudson. 19 Broad Street, Plattsburgh, N. Y.

Louis HussAKOF, American Museum of Natural History, New York City.

Jesse Hyde, School of Mines, Kingston, Ontario.

Robert T. Jackson. 195 Bay State Road, Boston, Mass.

E. C. Jeffrey, Harvard University, Cambridge. Mass.

Otto E. Jennings, Carnegie Museum, Pittsburgh, Pa.

W. S. W. Kew, 1522 Grove Street, Berkeley. Cal.

Edward M. Kindle, Geological Survey of Canada, Ottawa, Canada.

Edwin Kirk, U. S. Geological Survey, W:isbington. D. C.

Frank H. Knowlton. U. S. Geological Survey. Washington. D. C.

Lawrence M. Lambe, Geological Survey of Canada, Ottawa, Canada.

Frederick B. Loomis, Amherst College, Amherst. Mass.

Richard S. Lull, Yale University, New Haven, Conn.

D. D. Luther, Naples, N. Y.

Victor W. Lyon, Jeffersonville, Ind.

Thomas H. McBride, University of Iowa. Iowa City, Iowa.

J. H. McGregor, Columbia University, New York City.

Wendell C. Mansfield, U. S. Geological Survey, Washington, D. C.

Clara G. Mark. Department of Geology, Ohio State University, Columbus. O.

Bruce Martin, California Academy of Sciences, San Francisco. Cal.

George F. Matthew, 71.''» Germain Street, St. .Tohn. New Brun.swick.

W. D. Matthew, American Museum of Natural History, New York City.

T. PooLE Maynard, 321 James Building, Chattanooga. Tenn.

Maurice G. Mehl, University of Wisconsin. Madison. Wis.

John C. Merriam, University of California, Berkeley, Cal.

Rector D. Mesler, U. S. Geological Survey, W.Tshington, D. C.

Roy L. Moodie, University of Illinois, Chicago, 111.

Clarence L. Moody, University of California, Berkeley, Cal.

G. B. Moody. 2618 Etna Street, Berkeley, Cal.

W. O. Moody, 2618 Etna Street. Berkeley, Cal.

Robert B. Moran, 311 California Street, San Francisco, Cal.

William C. Morse. Ohio State University. Columbus. Ohio.

James E. Narraway. Department of .Justice, Ottawa, Canada.

Mar.jorie O'Coxnell, Adelphi College, Brooklyn, N. Y.

Henry F. Osborn, American Museum of Natural History. New York City.

R. W. Pack, U. S. Geological Survey, Washington, D. C.

Earl li. Packard, 1.522 Grovo Street, Berkeley. Cal.

WiLUAM A. Parks, University of Toronto. Toronto. Canada.

XII— Bull. Oeoi,. Ror. Am., Vot,. 26, tOH

164 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

William Patten. Dartmouth College, Hanover, X. H.

John R. Pemberton, Hydrographic Survey, Argentina.

O. A. Peteeson, Carnegie Museum. Pittsburgh. Pa.

Alexander Petrunkevitch, 266 Livingston Street. New Haven. Conn.

Charles S. Prosser, Ohio State University, Columbus. Ohio.

Percy E. Raymond. Museum of Comparative Zoology, Cambridge, Mass.

Chester A. Reeds, American Museum of Natural History, New York City.

E. S. RiGGS, Field Museum of Natural History, Chicago, HI.

Paul V. Roundy, U. S. Geological Survey, Washington, D. C.

Robert R. Rowley, Louisiana, Mo.

Rudolph Ruedemann, Education Building, Albany, N. Y.

Frederick W. Sardeson. 414 Harvard Street, Minneapolis. Minn.

Thomas D. Savage, University of Illinois, Urbana, 111.

Charles Schuchert, Yale University, New Haven, Conn,

William B. Scott. Princeton University. Princeton. N. J.

Henry M. Seely, Middlebury College, Middlebury, Vt.

Elias H. Sellards, Tallahassee, Fla.

Henry W. Shimer, Massachusetts Institute of Technology, Boston, Mass.

William J. Sinclair, Princeton University, Princeton, N. J.

Burnett Smith, Syracuse University, Syracuse, N. Y.

Frank Springer, U. S. National Museum, Washington, D. C.

T. W. Stanton. U. S. Geological Survey, Washington, D, C.

Clinton R. Stauffer, University of Minnesota, Minneapolis, Minn.

L. W. Stephenson, U. S. Geological Survey, Washington, D. C.

Charles H. Sternberg, Victoria Memorial Museum. Ottawa. Canada.

Chester Stock, 492 Seventh Street, San Francisco, Cal.

Charles K. Swartz, Johns Hopkins University, Baltimore, Md.

Mignon Talbot, Mt. Holyoke College, South Hadley. Mass.

Edgar E. Teller, 3321 Sycamore Street, Milwaukee, Wis.

Albert Thompson, American Museum of Natural History, New York City.

Edward L. Troxell. Amherst College. Amherst. Ma.'W.

William H. Twenhofel, University of Kansas, Lawrence, Kans.

M. W. Twitchell. Geological Survey of New Jersey. Trenton, N. J.

Edward O. Ulrich, U. S. Geological Survey, Washington, D. C.

Claude W. Unger, Pottsville. Pa.

Jacob Van Deloo, Education Building. Albany, N. Y.

Gilbert Van Ingen, Princeton University, Princeton, N. J.

Francis M. Van Tuyl, Department of Paleontology, Columbia University,

New York.
T. Wayland Vaughan, U. S. Geological Survey, Washington, D. C.
Anthony W. Vogdes. 2425 First Street. San Diego, Cal.
Charles D. Walcott, Smithsonian Institution, Washington, D. C.
Clarence A. Waring, Box 162, Mayfield. Cal.
Stuart Weller, University of Chicago, Chicago, 111.
David White, U. S. Geological Survey, Washington, D. C.
G. R. Wieland, Yale ITniversity, New Haven, Conn.
Henry S. Williams, Cornell University, Ithaca, N. Y.
Samuel W. Williston. University of Chicago. Chicago, 111.
Herrick E. Wilson. 224 W, College Street. Oberlin, Ohio.

LIST OF MEMBERS 165

William J. Wilson, Geological Survey of Canada, Ottawa, Canada.
Elviba Wood, Museum of Comparative Zoology, Harvard University, Cam-
bridge, Mass.

CORRESPONDENT DECEASED
E. KoKEN, died November 24, 1912.

MEMBERS DECEASED

Samuel Calvin, died April 17, 1911.
William M. Fontaine, died April 30, 1913.
Theodore M. Gill, died September 25, 1914.
Robert H. Gordon, died May 10, 1910.
J. C. Hawver, died May 15, 1914.

MEMBERS-ELECT

Albert Ti. Barkow.s, University of California, Berkeley, Cal.

WiNiB^KEu GoLDRiNG, New York State Museum. .Vlbany, N. Y.

John A. Guintyllo, Univer.sity of California, Berkeley, Cal.

WiNTHROP P. Haynes, Wellesley College, Wellesley, Mass.

Junius Henderson, University of Colorado, Boulder, Colo.

Charles C. Mook, American Museum of Natural History, New York City.

JoRGEN O. NoMLAND, University of California, Berkeley, Cal.

Charles E. Resser, U. S. National Museum, Washington, D. C.

Merton Y. Williams, Geological Survey of Canada, Ottawa, Canada.

Alice E. Wilson, Victoria Memorial Museum, Ottawa, Canada.

166 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

Minutes of the Fifth Annual Meeting of the Pacific Coast
Section of the Paleontological Society

C. A. Waring, Secretary

The fifth annual meeting of the Pacific Coast Section of the Paleon-
tological Society was held in divided session at Stanford University,
California, and at Seattle, Washington. The Stanford meeting was held
in the Geology Building, on Friday, April 24, 1914; the Seattle meeting
was held in Science Hall of the University of Washington, on Friday,
May 32, 1914. President J. C. Merriam presided at both meetings.

The relation of the paleontological series of the Pacific coast to that
of the Atlantic coast and outside areas, with special reference to methods
of correlation of the Triassic, Cretaceous, and Miocene, was suggested as
the general topic of discussion for the meeting of the Paleontological So-
ciety to be held in San Francisco in 1915. A motion was made and
carried ratifying this report as made by Doctor Merriam, chairman of the
Program Committee.

election of officers

The following officers were elected for the ensuing year :

President, Boy E. Dickerson, 114 Burnett Ave., San Francisco.
Vice-President, H. Hannibal, Stanford University.
Secretary-Treasurer , E. L, Packard, Berkeley, Cal.

It was voted to hold the next meeting at the call of the President.
Following are the programs and abstracts of the papers presented at
the two divisions :

PAPERS OF THE STANFORD MEETING
'NOTE ON THE CRETACEOUS ECHINODEIiMS OP CALIFORNIA

BY W, S. W. KEW

RELATIONS OF THE SANTA MARGARITA FORMATION IN THE COALINGA EAST

SIDE FIELD

BY JOHN H. RUCKMAN

(Abstract)

A discussion of evidences of unconformity with the Jacalitos above and Big
Blue below.

ABSTRACTS OF PAPERS 167

TENTATIVE CORRELATION TABLE OF THE NEOCENE OF CALIFORNIA

BY BRUCE L. CLAKK

FAUNA OF THE LOWER MONTEREY OF CONTRA COSTA COUNTY, CALIFORNIA

BY BRUCE L. CLARK

EXTINCT TOAD FROM RANCHO LA RREA
BY CHARLES L. CAMP

{Ah sir act)

Amphibian boues from Rancbo La Brea stiow tlie existence there of a toad
closely allied to present-day forms of the Pacific coast.

RODENTS OF RANCHO LA BREA
BY LEE R. DICE

(Abstract)

The rodents found at Rancho La Brea are closely related to the forms living
in the same region.

OCCURRENCE OF MAMMAL REMAINS IN THE ASPHALT BEDS OF MC KITTRICK,

CALIFORNIA

BY NEILL C. CORNWALL

{Abstract)

In the asphalt deposits of McKittrick certain mammal remains have been
found. These seem to indicate that the formation of the asphalt was not
later than Lower Pleistocene.

OUTLINE OF THE HISTORY OP THE CA8T0RIDJE
BY W. P. TAYLOR

(Abstract)

The beaver family was doubtless derived from Eocene Ischyromyidae. The
genera, Par aw j/s (Eocene), Sciuravus (Eocene), and Steneofiber (Oligocene
and Miocene), are near, if not actually, members of the phylogenetic series, of
which the genus Castor is the latest development. There have been probably
at least three beaver intercontinental migrations. The determinations of the
age of the Etchegoin formation bears directly on the problem of the first ap-
pearance of the genus Castor.

168 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

CRETACEOUS-EOCENE CONTACT IN THE ATLANTIC AND GULF COASTAL
» PLAIN

BY L. W. STEPHENSON

{Abstract)

The paper emphasizes the fact that the Cretaceous aud Eocene deposits of
the Atlantic and Gulf Coastal Plain are separated by an unconformity of
regional extent. Faunal evidence is offered to show that, in terms of geologic
time, this unconformity represents a very great hiatus. The differences ex-
hibited by the faunas on either side of the contact indicate changes greater
than those effected through evolutionary development during the time repre-
sented by the Exoyyra ponderosa and Exogyra custata zones of the Upper
Cretaceous ; the differences are also greater than the faunal changes effected
between the lowermost Eocene and the Recent, in the same province. The
unconformity marks a great diastrophic movement which involved the entire
Atlantic and Gulf Coastal Plain,

lONE FORMATION OF THE SIERRA NEVADA FOOTHILLS, A LOCAL FACIES OF

THE UPPER TEJON-EOCENE

BY BOY E. DICKEESON

{Abstract)

The lone, in part at least, is marine and of Tejon-Eocene age. Marine fossils
have been found in the upper portion of the lone formation at Marysville
Buttes, Oroville South Table Mountain, Merced Falls, and lone. Apparently
the same faunal zone, the Siphonalia siitterensis zone, is represented in all
these places.

STRATIORAPHIO AND FAUNAL RELATIONS OF THE LATER EOCENE OF THE .

PACIFIC COAST

BY HABOLD HANNIBAL

(Abstract)

Illustrated discussion of the stratigraphic and faunal relations of the Che-
halis, Olequa, and Arago formations of Oregon and Washington, and the Tejon
and lone formations of California,

FAUNA AND RELATIONS OF THE WHITE SHALES OF THE COALINOA

DISTRICT

BY JOHN H. BUCKMAN

VERTEBRATE FAUNA IN THE MARINE TERTIARY OF CALIFORNIA; THEIR
SIGNIFICANCE IN DETERMINING THE AGE OF CALIFORNIA TERTIARY
FORMATIONS

BY J. C. MERRIAM

AESTKACTS OF PAPERS 169

GEOLOGY OF A PORTION OF THE MC KFrTRICK OIL FIELD

BY G. C. GESTER

PAPERS OF THE UNIVERSITY OF WASHINGTON MEETING

8TRATIGRAPHIC AND FAUNAL RELATIONS OF THE LINCOLN FORMATION IN

WASHINGTON

BY CHARLES E. WEAVER

CRETACEOUS FAUNAS OF THE SANTA ANA MOUNTAINS
BY EARL L. PACKARD

(Aist7'act)

The Santa Ana Mountains afford a Chieo-Cretaceoiis section of simple
structure, yielding a rich invertebrate fauna, which is divisible into four
faunal zones. The section may serve as a faunal type section to which other
Chico localities may be referred.

REVIEW OF THE FAUNA OF THE RATTLESNAKE PLIOCENE OF EASTERN

OREGON

BY JOHN C. MERBIAM

(Abstract)

The Rattlesnake formation of the .John Day Valley contains a fauna which
has been presumed to be of late Miocene or early Pliocene age. The material
known from this formation is very fragmentary and commonly of uncertain
occurrence. The paper i)resents a review of the fauna, with a statement as
to the probable age and correlation of the formation.

EOCENE OF THE COWLITZ VALLEY
BY CHARLES E. WEAVER

FAUNA OF THE SIPHONALIA SUTTERENSIS ZONE IN THE ROSE BURG

QUADRANGLE, OREGON

BY ROY E. DICKERSON

(Abstract)

A collection made by Mr. Bruce Martin from the Umpqua formation, on the
Umpqua River, at the mouth of Little River, contains several forms, such as
Cbrt/finfloninis uiarthii, Cardimii mnrjfuvillrnsis, FUpboimUn siittrrrnsifi, Cnri-
crlla stoiwsiana. S)nyiil.n dovininna. and Vrnrrirnrdia phniicosfn. new v;iriety.
which are characteristic of the fiipbniialio sutirrensis 7,one of the Tejon group

J70 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

of California. The paper presents a fauna obtained from the Umpqua for-
mation and a tentative correlation of the beds containing the fauna with the
uppermost Tejon of the California province.

EVOLUTION OF THE PACIFIC COAST M ACRID JE
BY EABt, L. PACKARD

{Abstract)

The genus Spisiila, represented in the Horsetown beds by Spisula ashburneri
(Gabb) became dominant in the Middle Miocene, thence gradually declining
to the present day. The earliest undoubted mactroid species occurs in the
Miocene, reaching its greatest development at the present time. The mulinoid
forms appeared suddenly in the early ]\Iiocene, spread rapidly, and then
quickly disappeared from the region north of Mexico.

CORRELATION OF THE TERTIARY FORMATIONS IN WESTERN WASHINGTON

BY CHARLES E. WEAVER

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA
Vol. 26, pp. 171-204 March 31, 1915

ISOSTASY AND EADIOACTIVITY '

PRESIDENTIAL ADDRESS BY GEORGE F. BECKER

{Read before the Socieltj December 2'.), IDlJf)

CONTENTS

Page

Introductory ITl

Premonitions of isostasy 172

Direct investigations of isostiisy 178

Discussion of isostasy 185

Note on epeirogeuy 188

Recent advances in radiology 189

On tlie earth's radiation 195

I 'Onclusions -02

Introductory

It is the purpose of this paper to point out some apparent discrepancies
between the observations of geodesists on isostasy and the inferences
which some radiologists have drawn as to the great age of certain speci-
mens of minerals. It seems well to begin by reviewing the results of
isostatic investigations, in order to estimate the degree of confidence to
which they are entitled; and recent advances in radiology demand similar
attention.

Correlation of these widely distinct researches is possible because it
happens that the emission of heat by a globe whose excess temperature is
due solely to radioactivity obeys Fourier's law exactly as does that emitted
by a hot but radioinactive 'globe. It is tims easy to plot the distribution
of temperature in a globe which at the consistentior status had a high
temperature due in part to radioactivity and in part to compression, the
diagram being strictly analogous to that given l)y Kelvin for a cooling
globe.^ By trial and error it is possible to obtain an approximate answer
to the question whether in the present state of science it can be admitted
that the greater part of the heat radiated 1)\ the earth is of radioactive
origin ;iiiil wliother approximately complete isostatic compensation ;it such

' Manuscript receivod by Hio Socrot.ii-y of (ho Society Decpmhpr 20, 1014.

By reason of illness, Dr. Becker was unable to present his paper in person.
2 Nat. Phil., part 2, p. 477.

XIII— Bull. Gkol. Soc. Am., Vol. 26, 1914 (171)

172 Cx. F. BECKER ISOSTASY AND RADIOACTIVITY

deptlis as are reported by the geodesists is compatible with the lapse of
something- like a thousand million years since the ocean was gathered
together.

Geolog}' as a science is conditioned by the state of the earth's interior
and our knowledge of its constitution is now advancing. So late as the
foundation of this Society, in 1889, the Cartesian doctrine of a fluid
earth, inclosed in a very rigid shell, a score or two of miles in thickness,
was held by most geologists. We now know that the globe is solid and,
on the whole, of great rigidity, and probably divisible into at least four
distinct shells, each more rigid than that overlying it;^ that the irregu-
larities in density and structure, which are so marked at the surface,
extend only to a depth of something like a fiftieth of the earth's radius;
that open cavities or cracks may exist at depths of 20 miles and very
possibly down to the level of isostatic compensation. We know, too, that
the earth is radioactive, but tliat the radioactivity is superficial, reaching
only to a moderate, though uncertain, level; we also know, however, that
the earth's heat is not wholly of radioactive origin. ]\]"ore information
is certainly in store for us, for Mr. Michelson is now measuring the
terrestrial tides in terms of the wave-length of light,* while methods
have been developed by which the distribution of density above the level
of isostatic compensation can be studied.

Thus the future is full of hope. The rational method of attaining it
is to make trial hypotheses and to devise methods of testing them.

Premonitions of Isostasy

Observations bearing on the problem of isostasy are as old as geodesy
itself. During the measurement of the Peruvian arc, 1T35 to 1745,
Pierre Bouguer^ observed and computed the attraction of Chimborazo.

^ L. Geiger and B. Gutenberg, continuing Investigations by Wiechert, Zoeppritz, and
themselves on the intensity of longitudinal and transverse earthquake waves, find in the
earth three surfaces of discontinuity at depths of 1,1^^3, 1,712, and 2.454 kilometers.
The values found for Poisson's ratio only slightly exceed one-fourth. Gottingen, Nach-
richten, 1912, p. 675.

* The first attempts to measure bodily tides in the earth were made by George H. and
Horace Darwin with the horizontal pendulum, but without satisfactory results. Better
success attended the experiments by B. von Rebeur-Pashwitz with a similar instrument.
O. Hecker at Potsdam, in 1907, and A. Orloff at Dorpat, in 1911, demonstrated small
terrestrial tides and the high rigidity of the earth, also with the horizontal pendulum.
Their results and others were discussed by W. Schweydar, Roy. Preus. Geod. Inst, 1912.
To obviate certain difficulties and uncertainties attending the use of the horizontal pendu-
lum. A. A. Michelson is experimenting with an apparatus consisting of two water-levels
(acting on the principle of a spirit-level) at right angles to one another, each about 500
feet long. Astrophys. Jour., vol. 39, 1914, p. 97.

■^ La figure de la terre, 1749, p. 379. On page .391 he remarks that mountains attract
much less than the greatness of their volume would promise.

PREMONITIONS OF ISOSTASY 173

From the unexpectedly small observed deflection of the vertical he in-
ferred, just as a modern geodesist would have done, that the volcano
must contain cavities. On tiie other hand, Charles Hutton" perverted
I lie attraction of Schehallien to a determination of the density of the
earth and entertained a poor opinion'^ of Cavendish's method,* now be-
come the standard means of determining this constant. Tliitton, how-
ever, introduced the method of dissecting a mountain mass into elements
bounded by two horizontal planes, tM-o vertical cylindrical surfaces, and
I wo vertical planes, radiating from tlio station, wliicli is still in use
much as he developed it.

Laplace seems to have been the first to grasp the problem of isostasy.
In 1818 he pointed out that Bouguer's pendulum experiments at Quito
demonstrate that the Cordillera is of very low density, far smaller than
the mean density of the earth, which, following C^avendish, he takes at
5.5. This is a distinct recognition of compensation. Between the years
1735 and 1818 a considerable uimiber of observations in both hemispheres
had been made on the length of the pendulum beating seconds, and dis-
cussion of these, together Avith measurements of degrees and lunar obser-
vations, led Laplace to conclusions which may be expressed as follows:
The earth was once liquid and shells of equal density were approximately
spherical; it solidified throughout, for the most part with very slight
changes of configuration or disturbances of isostasy, and the irregularities
manifest at the surface then extended and still extend to a very small
depth compared with the earth's radius. The argument for the super-
ficiality of these irregularities, as I understand it, is substantially that
if Legendre's law of density (often referred to as Laplace's law) is as-
sumed, the computed attractions agree with those observed extremely
well, l)etter than they could agree if such irregularities in the distribution
of mass as are observahle at tlie surface prevailed at great depths.^ I
find nothing like a rigorous demonstration of this probable thesis.

«PhiI. Trans., London, 1778. Button's Abridgment, vol. 14, p. 408.

■^ Phil. Trans.. London. 1821, Part I, p. 276.

" Phil. Trans.. London, 1798, p. 469.

" Laplace's memoir on the figure of the earth appeared in the M^moires de I'Acad^mle
for 1817, printed in 1819. It is reprinted in his complete works, vol. 12, 1807. It Is
only partially reproduced in the chapter on the figure of the earth in Book XI of the
M<5canique r<?leste. A summary Is given in the memoir, but not in the magnum opus.

His mathematical analysis he says :

. . "compared with pendulum determinations, with the measurements of degrees,
and with lunar observations leads to these results :

"1. The density of the shells of the terrestrial spheroid Increases from the surface to
(he center.

"2. These shells are to a close appro\-iniaH<)n symniotrlcal with reference to the renter
of gravity.

".S. The surface of this spheroid, a part of which Is covered by the sea, has a flgure

174 G. F. BECKER ISOSTASY AND RADIOACTIVITY

In 1849 stokes^" showed that to the first order of small quantities the
relation between gravit}^ and latitude discovered by Clairaut can be de-
duced from the Newtonian law of gravitation without any explicit as-
sumption as to the form of shells of uniform density. The only express
assumption made is that equipotential surfaces, external or internal, are
approximately spherical. It follows that the mean figure of the earth,
though not its dimensions, can he determined from pendulum observa-
tions alone, a task actually performed some time later by the famous
geodesist, F. R. Helmert."

differing but little from that which it would asi5ume in virtue of the laws of equilibrium
if, the sea ceasing to cover it, the spheroid were to become fluid.

"4. The depth of the sea is a small fraction of the difference between the two axes of
the earth.

"5. The irregularities of the earth and the causes which disturb its surface extend to
but a small depth.

"6. Finally, the whole earth was originally fluid.

"These results of analysis, observation, and experiment ought, it seems to me, to be
set down among the few truths which geology' has to offer."

Laplafp in many passages refers to the earth as solid. The liquid shells, he says,
"would changp their shape only very slightly during solidification." Nearly a century
has elap.'jed since these conclusions of Laplace were made known, yet it is dotibtful
whether they could be modified to advantage.

In this memoir Laplace is by many supposed to have extended Clairaut's theorem on
the variation of gravity with latitude ; but Todhunter's review in his histoiT of the
theories of attraction and the figure of the earth, vol. 1, p. 229, denies this, splendid as
he considers Laplace"s analysis. Clairaut did not assume, according to Todhunter, that
the component shells were fluid or of the configuration corresponding to fluidity, but
only that the bounding outer surface has the same form as if it were fluid, and that it is
in relative equilibrium when rotating with uniform angular velocity. In the 11th edi-
tion of the Encyc. Brit, the article on the figure of the earth is by Clarke, revised by
Helmert, and in it Todhunter's conclusion is accepted.

10 Stokes published two papers on this subject : Camb. and Dublin Math. .Tour., vol. 4.
1849, p. 194. and Trans. Camb. Thil. Soc, vol. 8, 1849. p. 672. Both are included in his
Collected Papers.

" Stokes's investigation has been extended by Helmert, who has added to the expres-
sion for the variation of gravity with latitude a small negative term of the second order,

which is maximum in latitude 45°, and there amounts to 7 X lO"*" times gravity at the
equator. All modern geodesists accept Helmert's emendation, which is in accord with
investigations by George H. Darwin and E. AViechert, indicating a depression of sealevel
in latitude 45° of some 3 meters. Besides being an essential part of the history of the
subject, this correction serves to show how very nearly the geoid coincides with the
ellipsoid excepting for local attractions.

For a rotating homogeneous mass without rigidity the only figure of equilibrium is an
oblate ellipsoid. Strictly speaking, this figure is that of equilibrium only for the case of
homogeneity. The external equipotential surface of a heterogeneous globe, in which the
masses are either liquid or disposed as if they were liquid, is represented by an algebraic
equation of the tenth degree, differing but little, however, from an ellipsoid. The equa-
tion of the potential, V, may be written as in Pratt's Figure of the Earth, article 122,

Here /a. = z'r and of course r^ = x'^ -\- ■tp -'r i*.
Making V = C, a constant,

PREMONITIONS OF ISOSTASY 175

Though no explicit assumption was made by Stokes as to the distri-
bution of density, there is none the less a very important implicit postu-
late. It requires no analysis to show that if there were very great
irregularities in the distribution of density the level surfaces or equipo-
tentials of the globe would not necessarily be approximately spherical,
and it is essential to make some estimate of the degree of irregularity
implied in Stokes's theorem.

Clairaut's theorem is expressed in terms of the flattening or ellipticity
of the earth, known to be about 1/298 (though possibly it is a little
larger), and is denoted by e.^- If the mean radius of the earth is taken
as unity, e is 1/298 of a radian, or 11' 32" = 692". Stokes neglects all
terms in e^, and e^ is equivalent to 2". 3. Now if the ellipsoid of revolu-
tion whose ellipticity is e is an equipotential surface, it is easy to prove
that the maximum angle between the normal to the equipotential surface
and the radius vector is e. Stokes's theorem is consequently true only of
an earth on which the angle between the geocentric vector and the normal
to the geoid does not exceed a quantity of the same order as e. Otherwise
expressed, its truth is limited to cases in which the deflection of the ver-
tical is of the order of e-. Now observation shows that a deflection of
23" is, relatively speaking, very large. Mr. Hayford in his first memoir,
which will presently be noticed more at length, records the observed de-
flection at 509 stations, and only at 7 of them does this exceed 20", the
highest approaching 30", which is also about the maximum observed in
any country. At seven-eighths of these stations the deflection is less
than 10".

Thus, closely enough, the assumption implied in Stokes's theorem may
be said to be that

e + 23" = e + e/30 = 1.033 e

is to be regarded as of the same order of magnitude as e or, since

23" = 10 e-,

substituting the value of r and squaring each side of this equation reduces it to the re-
quired algebraic form. E is the earth's mass, e the ellipticity of the meridian, a the
mean radius of the earth's surface, ;• the geocentric radius vector, and m the ratio of
centrifugal force at. the equator to gravity at the equator.

The geoid Is a far more complex solid, being one in which all irregularities due to
local attraction are superposed upon the surface of the tenth degree. The maximum de-
parture of the geoid from the theoretical spheroid is supposed to be about 100 meters
and to occur under "the roof of tlie world" in central Asia,

"Stokes extends the application of the term ellipticity to a slightly irregular figure,
such as the geoid, or sealevel surface. At a distance from the eartli such as that of the
moon, the attraction of the geoid would coincide with that of the mean ellipsoid; conse-
quently the mean flattening of the geoid may be regarded as the ellipticity of the mean
ellipsoidal spheroid.

176 G. F. BECKER ISOSTASY AND RADIOACTIVITY

that quantities as great as 10 e^ may be neglected in determining the
mean figure of the earth. ,

To illustrate in terms of geology the. meaning of these figures, suppose
a spherical batholith of peridotite embedded in the outer shell of a
spherical earth, so as just to reach the surface at its uppermost point, and
consider what must be the radius of the batholith to produce a certain
maximum deflection. The problem is a very simple one and has been
fully discussed. ^^ Taking the earth's mean density at 5.5 and the surface
density at 2.75, let the peridotite have a density of 3.25. Then if the
batholith is to produce a maximum deflection of 23", it appears that the
radius of the batholith must be 414 miles; that it will produce this de-
flection at a distance of 3 miles from its point of contact with the surface,
and that just above its highest point it would raise the surface of the sea
or of the geoid by 2 feet 2 inches.

No geologist would be surprised at the occurrence of a batholith whose
greatest dimension is 8i/^ miles or at the contiguity of rocks whose densi-
ties differ by 0.5. Now since Stokes's postulate applies not merely to the
external equipotential surface, but also to the interior level surfaces of
the globe, it would appear that such a batholith as that described repre-
sents the order of magnitude of the largest heterogeneities occurring
anywhere in the globe.

Possibly this agreement might be pushed a little farther. Various,
phenomena show that the ellipticity of the equipotential surfaces dimin-
ishes from the exterior of the earth to its center, and so also must e/30
or 10 e' If this quantity measures the heterogeneity, then this must also
diminish toward the center ; but it would be very unsafe to conclude from

1* It may be well to note here the formuljc for the effects produced by a spherical
batholith. The proof may be found- in Thomson and Tait, Nat. Phil., sections 786 and
787. Let a be the radius of the earth supposed spherical and r the radius of the batho-
lith. Let c r be the depth of the center of the batholith, p' its density, and p the
density of the earth's surface, while a is the earth's mean density. If i// is the maxi-
mum deflection of the plumb-line due to the attraction of the batholith

r _\/ W a c-
o" " 2~ p'—p *

The elevation of the geoid over the central point of the batholith is, say, h and

A = p'— p !:°

a a- c a-

In the text results are given for the very high value for >(/, 2.3' '. Far commoner, though
still high, would be 10'' =0.0000 4848 radi'ans. With p'--p =0.5 and c=l, this gives
»/a = 0.00046, and with a =: 4,000 miles, » = 1.84 miles. Then h would be nearly 5
inches.

It should be observed that the internal variations in density considered in this note
differ essentially from the variations in external form which lead to the larger irregu-
larities of the geoid. The great mass of the Thibetian Mountains stands above or outside
of the geoid.

PREMONITIONS OF ISOSTASY 177

such reasoning more than that conditions are quite compatible with the
hypothesis of increase of homogeneity with deptli.

Thus it follows from Stokes's theorem that the observed deflections of
tlie plumb-line may be due entirely to the heterogeneity of the earth's
outer sbell; but it does not follow tbat only the outer layer is heteroge-
neous. If the center of the batholith I have imagined were at 8I/2 miles
beneath the surface instead of at 414 miles, its mass remaining un-
changed, it would cause a deflection of only a fourth of 23" or, say, 6".
Consequently deflections alone give no direct information as to the dis-
tribution of density in depth.

If indeed it could be assumed that the primitive earth was fluid
throughout, or to a great depth from its temporary surface, such irregu-
larities as are observed at the present surface could scarcely be supposed
to exist far below it. To be sure, there is seemingly no limit to thinkable
viscosity; an earth can be imagined so viscous that density would not
efi'ectively control configuration. But there is enough evidence of gravi-
tative differentiation of rocks to show that many magmas yield at a sensi-
ble rate to the stresses produced, even by very small phenocrystic crystals,
and therefore with much greater velocity to bodies of batholithic dimen-
sions. The respective velocities for highly viscous magmas are doubtless
proportional to the cross-sections.

Laplace, Pratt, and Kelvin were all convinced that the earth had been
fluid originally, while Stokes considered the evidence very strong, though
not conclusive. Recent investigations in isostasy strengthen this evi-
dence and seem to confirm Laplace's view as to the superficiality of the
heterogeneous shell. ^*

So far as I can see, the investigations which have been passed in review
lead to no definitive conclusion as to tbe condition of tlie interior of the
earth, although they leave no question that the material of the globe is
arranged nearly as if it had been fluid. On the other hand, they estab-
lish a presumption that irregularities in density, such as are encountered

"Thomson and Talt (Nat. Phil., 1883, section 821) summarize tlie evidence then avail-
able as follows :

"There is, as we shall see in later volumes, a great variety of convincing evidence In
support of the common geological hypothesis that the upper crust was at one time all
melted by heat. This would account for the general agreement of the boundary of the
solid with that of fluid equilibrium, though largely disturbed by uitheaval and shrinkiugs
In the process of solidiru'atioii, which has probably been going on for a few miUiou years,
but is not quite complete (witness lava llowing from still active volcanoes). Tbe oblate-
ness of (lie deeper layers of e(iual density vvliicli we now infer from the ligure of sealevel,
the observed density of the upper crust, and Cavendish's weighing of the earth as a
whole, renders it highly probable that the earth has been at one time melted not merely
all round its surface, l)ul either throughout or to a great deptli all round."

It is probable (hat the liquid portion of the earth was approximately In couvectlve
equilibrium, and that consolidation began at the centei*.

178 G. F. BECKER ISOSTASY AND RADIOACTIVITY

at the surface, are confined to a superficial shell; in other words, they
lend probability to the hypothesis that a level of approximate isostatic;
compensation underlies an heterogeneous external shell.

Direct Investigations of Isostasy

Turning now to researches addressed more directly to elucidating the
conditions existing in the earth's superficial shell. Sir John Herschel and
Charles Babbage seem to have been the first to indicate a tendency to
isostasy as the controlling factor in at least some recent upheavals and
subsidences.^^ Babbage confined himself to eft'ects of temperature change.
Herschel relied on "the variation of the pressure, and the infinity of sup-
ports broken by weight, or softened by heat, to jn-oduce tilts." He finds
in erosion and deposition the primuvi mobile of geology through the sub-
version uf equilibrium of pressure. Neither of these authorities appears
to have pursued the matter, nor was the subject resumed for many years.

Archdeacon John H. Pratt, in 1855, called attention to the fact that
the attraction of the Himalayan range produces in the plains of India a
deflection of the plumb-line far smaller than was to have been expected,
but he then ofliered no satisfactory explanation.^*' Airy in the same year
attempted to explain the facts by the hypothesis that the solid crust of
the liquid earth, supposed only a score or two of miles in thickness, extends
downward under mountain chains and is of relatively small density,
while beneath the oceans it is thin, the whole crust being supported by
fiotation.^^ In answer Pratt pointed out that no possible law of cooling
could produce such a crust as Airy described, and furthermore that W.
Hopkins^^ had shown the crust to be at least 900 miles thick and prob-
ably more than 1,000 miles. ^^ But in 1858 Airy's hypothesis gave Pratt
an idea, namely, that although the earth is solid to a very great depth, if
not throughout, there is a relative deficiency of matter under mountain
ranges and relative excess of matter beneath oceanic depressions; in short,
an approach to isostasy.'" This idea, not unknown to Laplace, he elab-
orated in a number of papers, most authoritatively, of course, in his well
known work on Laplace's Functions and the Figure of the Earth.^^

1^ Babbage's paper on the Temple of Serapis was read before the Geol. Soc. Lond. iu
March, 1834, but published in full in the Proceedings, vol. 3, 1847, p. 186. Herschel's
letters to Leyell and Murchisou were printed in I'roc. Geol. Soc. Lend., vol. 2, 1833-1838,
pp. 548 and 596.

i" Phil. Trans., vol. 145, 1855, p. 53.

" Phil. Trans., vol. 155, 1855, p. 101.

i»Phll. Trans., 1830 to 1842.

1" Airy does not seem to have made any reply at the time, but in a popular lecture in
1878, Nature, vol. 18, 1878, p. 43, again expressed his belief in a lumpy crust.

-^ Phil. Trans., vol. 149, 1859, p. 747.

21 The copy before me is the 4th edition, 1871.

DIRECT INVESTIGATIONS OF ISOSTASY 179

Geodesists, I have been tokl, were well aware for many years that with
sufficient labor it would be possible to test Pratt's theory, to which C. E.
Button gave the name isostasy.-- They recognized, however, that the
task would be a very formidable one. As we all know, it was at last
undertaken by Mr. John F. Hayford,"^ in what Mr. Helmert character-
izes as a "truly magnificent investigation.'' The same veteran geodesist
renamed the underlying idea "the Pratt-Hayford hypothesis" in recog-
nition of the importance of Hayford's work in establishing the actuality
of isostasy.

Mr. Hayford's second memoir-'* is a supplement to the first and the two
should be considered together. In all they embrace and discuss 765 de-
flections of the vertical in the United States. In the nature of the case,
isostasy can be investigated only by trial and error. Among many hy-
potheses, reasonable or unreasonable, as to the distribution of isostatic
compensation, one is selected and all of the deflections are computed as
if it were true. The results of such a discussion are called by Mr. Hay-
ford a "solution." Those portions of the deflections which remain unex-
plained after each solution are known as residuals. Pretty nearly, but not
exactly, a residual is the difference between the observed deflection and
the computed deflection.-^ This is not an exact definition because the
observed deflection involves errors of observation and instrumental errors,
while the computed deflection may be inaccurate from many causes; thus
the maps from which the volume of topographic features is derived are
not perfectly accurate, nor is the density of the rocks accurately known,
while the determination of the latitude, longitude, azimut]i, zenith, etcet-
era, are all to some extent imperfect. The residuals include errors of all
descriptions, and would reduce to zero only if ideal conditions were dealt
with by infallible observers and computers. Among trial hypotheses that
is the best in which the sum of the squares of the residuals is smallest.

For each observed deflection Mr. Hayford computes the deflection
which would be produced by all the topography within 2,564 miles or
4,126 kilometers.-^ This so-called topographic deflection (or perhaps
better orographic deflection) always differs from the observed deflection
in the sense to be expected on the hypothesis of isostatic compensation —

-" Phil. Soc. Washington, vol. ii, 1889, p. 51.

'■a The flgure of the earth and Isostasy from mcasiirt'iiifuts iu the U. S. Coast and
Geod. Surv., 1000.

-* SuppU'iiieiilary iiivesi in;! I ion in I'.Kiil of the ligiire of the earth ;in(l isostasy. t'oast
and Ceod. Surv., 1010.

-'^ C"f. Hayford's first moiioKra|)h, p. lOO, and his second nionosi'aph, p. tiO, footnote.

=» Helmert considers 1,000 kilometers a sufficient radius, and disagrees witli Hayford's
method of dealing with the more distant masses. Sitzungsber. k. I'reuss. Akad. der Wlss.,
1914, p. 440.

180 G. p. BECKER ISOSTASY AND RADIOACTIVITY

that is, mountains attract less than would be anticipated from their vol-
ume, as if they overlay regions of relatively small density ; while lakes or
other depressions diminish the attraction less than would be expected if
the underlying material were of average density.

Mr. Hayford has considered eight trial hypotheses as to the distribu-
tio]i of compensation, of which five suppose uniform distribution each to
some particular depth. Of these, two represent extremes; one, solution
B,-" supposes the depth infinite, which is equivalent to assuming that
there is no compensation at all, while the other solution, A, assumes that
it is complete at the surface, which amoimts to the assumption that topo-
graphic forms exert no effect on the direction of the vertical. Three solu-
tions, called E, H, and G, assume uniform complete compensation at
depths of 162.2 kilometers, 120.9 kilometers, and 113.7 kilometers re-
spectively. Three other hypotheses which deal with selected representa-
tive data are (1) that compensation is confined to a layer 10 miles in
thickness at a mean depth to be determined, and which turns out to be 40
miles; (2) that it diminishes uniformly from the surface; (3) that it
diminishes by a law suggested by Mr. T. C. Chamberlin.

Discussion of the residuals by least squares at once throws out the hy-
potheses of no compensation or of compensation complete at the surface.
Hence there really is compensation nearly or quite complete at a finite
depth. Thus Hayford has proved Laplace's dictum that the irregulari-
ties of the earth and the causes which disturb its surface extend to but a
small depth compared with the earth's radius. Of the three hypothetical
depths for imiform compensation, solution H, or 120.9 kilometers, gives
the smallest sum of the squares of the residuals, and this sum is less than
a tenth of that found on the assumption that there is no compensation.
Compared with the opposite extreme of complete surface compensation,
the sum of the squares of the residuals for solution H is 53 per cent.
Thus for miiform distribution the depth of complete compensation is
near 120 kilometers.

As might have been anticipated from Stokes's investigation, however,
the defiections of the vertical do not decide between various configurations
of compensation. Within the limits of errors of observation a compen-
sating layer 10 miles thick, at a mean depth of 40 miles, or a wedge,
widest at the surface and extending to a depth of 117 miles (or having

^ Solution B corresponds to the Bouguer reduction. Althougli Boiigner recognized that
some mountains did not exert the attraction he expected of them, he would have been
rash to assume that a mountainous conformation was in general attended by correspond-
ing subterranean defleiencies of mass. Helmert 30 years ago found it best, as suggested
by Faye, to rely on the free-air reduction, or solution A, which leads to errors in a sense
opposite to those of Bonguer"s reduction, but affords a closer approximation to the ob-
served deflections. Sitzangsber. k. Preuss. Akad. der Wiss., 1912, Jan. to June, p. 308.

DIRECT INVESTIGATIONS OF ISOSTASY 181

its center of inertia at 39 miles), will satisfy the conditions as well as a
uniform compensation to a depth of 76 miles or 132 kilometers.-^

In 1913 Hayford and Bowie published a memoir on the effect of topog-
raphy and isostatic compensation on the intensity of gravitation.^^ For
105 stations they computed the effect of the topographic features of the
entire earth on attraction at the station and assumed uniformly dis-
tributed compensation complete at a depth of 113.7 kilometers, corre-
sponding to solution G of Mr. Hayford's investigations. This study was
begun before Mr. Hayford had reached the conclusion that 133 kilometers
is more probable than the smaller depth, but Hayford and Bowie show
that the difference in the conclusions reached would be negligibly small.

While their results are confirmatory of the hypothesis of compensation,
studies of the intensity of gravitation are very inferior to the deflection
method for the determination of the depth of the level at whic;]i com-
pensation is complete.

As in the former investigation, Hayford deduced residuals ; so here he
and Bowie obtain from comparison of observations and computations
what they call new method anomalies. These consist of observed in-
tensities less computed intensities plus a small constant systematic cor-
rection to the Helmert formula of 1901. This correction is onlv 0.009
dyne, and if it were applicable at the equator would reduce gravity there
to 978.039 dynes.^" Like the residual, an anomaly lumps together all
sorts of errors of assumption and observation. Two of its components
are of special geological importance. If compensation is supposed com-
plete and there were no errors in maps or mean density and the like, then
for a given region the new method anomaly, if positive, would indicate
excess of material or of pressure, an overload. Similarly a negative
anomaly would be interpreted as a deficiency of mass in the column
underlying the surface area; but an anomaly might equally well be due
to irregular distribution of compensation. A very moderate batholith of
peridotite just below the station might be accurately compensated by
deficiency of mass at a depth of 50 miles so that there would be complete

2* Although these compensating excesses or deficiencies of matter cannot be considereil,
strictly speaking, as concentrated at their centers of inertia, the depths of these points
are not very different ; 40 miles for the thin layer, 89 for the wedge, 38 for a shell
reaching the surl'acc.

^ The effect of topography and isostatic compensation on the intensity of gravity.
Coast and Oeod. Siirv., IDlL'.

=«* Helmert's foriimla ol' IDOl, <.ii Hit- Potsdam system, for the tlicori'tical value of
gravity at seaJevd is

yo = 978.030 ( 1 4- Ii.il()o30'2 sin^ <f> — O OOOOOT sin- ■-' </))

The corresponding formula of Hayford and Bowie on which tlulr "new method anom-
alies" are based is

7u ^ 978.039 (I + 0 U0o302 sin* <f> — O.0O0OO7 sin- ■! </>).

182 G. P. BECKER ISOSTASY AND RADIOACTIVITY

isostasy at 120 kilometers and yet produce a very considerable anomaly
at the surface. If this batholith were 4^4 miles in radius, as in a previous
example, and only just buried, it would increase the attraction by 0.094
dynes, which is almost exactly the largest anomaly detected in the United
States, the mean anomaly being only 0.01 T dyne.

Hayford and Bowie compare their anomalies with what they call the
Bouguer and free-air anomalies. Of these the former corresponds to
solution B and implies that there is no compensation, or that the earth
is infinitely rigid. The free-air anomalies answer to solution A and
imply that topographic forms exert no attraction. Comparison shows
that the new method anomalies are only a fourth as great as the Bouguer
anomalies if all stations are considered, whereas if only mountainous
regions (whei'e the Bouguer correction is of great moment) are included
this is twelve times as large as the Hayford and Bowie anomaly. As
has long been known, total neglect of the attraction of mountains gives
better results than their consideration by Bouguer's methods; but in
mountainous areas the new method anomalies are only a third as great
as the free-air anomalies.

Hayford's investigations on deflection were confined to the United
States. Hayford and Bowie's study of the intensity of gravity included
89 stations in the United States, besides 16 selected stations outside of
that area, and scattered all over the world, seven of them being at sea
and having been occupied by Mr. 0. Hecker, of whose work more will be
said presently. In Switzerland the method developed by Hayford and
Bowie has been applied to 13 stations. This is too small a number to
give strong evidence, but, so far as it has gone, the investigation indicates
an isostatic condition in that country of mountains and a mean anomaly
scarcely differing from that in the United States.^^ Mr. Bowie has also
discussed 14 gravity stations in British India. ^- The number is again
very small, but the results tend strongly to confirm those obtained in this
country.

That eminent veteran in geodesy, Mr. F. R. Helmert, has not only
expressed the warmest interest in the American investigations on isostasy,
but has made very important contributions of his own to the subject.
While Hayford determined the level of isostatic compensation from de-
flections of the vertical alone, Helmert devised a method of finding this
level from observations on the intensity of gravity without reference to
deflections, the numerical result being substantially the same. This ac-
cordance is most gratifying. A conclusion i-eached in only one way can

2^ Hayford and Bowie, p. 122.

32 Jour. Wash. Acad., vol. 4, 1911, p. 245.

DIRECT INVESTIGATIONS OP ISOSTASY 183

never be quite free from the suspicion of some hidden fallacy, while a
result obtained by independent methods commands great confidence.

Mr. Helmcrt's method, printed as long ago as 1909,^^ is applicable only
at selected stations, Avliere a rather level coastal plain and a tolerably
deep sea are connected by a fairly smooth and steep slope. The coast
must also be assumed to be part of a great circle. On the hypothesis
that there is a level of isostatic compensation, it is easy to prove that in
such a region the intensity of gravity will reach a maximum at the shore
and a minimum at the junction of the submarine slope with the level
sea-bottom; and from the observations it is possible to make a choice
between various assumptions as to the depth of the level of isostatic
compensation. Like Hayford, Helmert prefers the hypothesis that com-
pensation is uniformly distributed.

IMr. Helmert found on record 51 localities, widely distributed over
the world, which were suitable for treatment by his method. From them
lie deduced for the depth of the level in (|uestion as a simple mean
118 d= 2;;J kilometers; but he tonk tlio superficial density of the earth at
2.73, while Hayford assumed it at 2.67. In a second paper Helmert so
modified Hayford's equations as to render them suitable for the compu-
tation of the mean and probable errors and, with the superficial density
2.67., derived from them a depth of 123.5 ± 14 kilometers mean error.'"*^
Assuming the same superficial density of the earth, Helmert finds from
his own investigation 124 ± 22 kilometers mean error. That the two
results substantiate one another is evident ; indeed, so close an agreement,
apart from the error, must be considered accidental, and in later papers
Helmert rounds off the figures to 120 kilometers. He points out that
his mean error of ± 22 kilometers is larger than Hayford's and suggests
that this may be due to the world-wide distribution of his stations.^®

At Mr. Helmert's instance, Mr. 0. Hecker made several voyages in
the first years of the century for the purpose of determining the intensity
of gravity at sea. The method employed was devised by Mr. H. Molin,
who found that the gravity correction of the quicksilver barometer on
land could be determined by the help of the boiling-point thermometer.^'"'
This method carried out on a moving vessel is not of a high degree of

^Sitznngsber. k. Preuss. Akad. der Wiss.. lilOO, July to Doc. p. 1192.

3* The probable error as derived from the theory of least squares is ± 0 kilometers.
The actual errors are probably larger than the probable eri-ors because of undetected
systematic errors. As I understand it, Helmert takes (he moan error in order to leave a
margin for undetected errors. The difference is a mere estimate, not a conclusion from
theory. The mean error is 1.4S2fi times the prnbnble error.

■'^■' Sltzungsbor. k. I'reuss. Akad. dor Wiss., 1011. .T.in. to .rune. p. 10.

■"^ Sltzungsber. k. Preuss. Akad, der Wls.s., 1902, p. 120, and Enoyc. der Math. Wiss.,
vols. 6, 1, 7, p. 125.

184 G. F. BECKER ISOSTASY AND RADIOACTIVITY

accuracy^ but yet accurate enough to establish a fact of great importance,
namely, that over the widely extended oceans of nearly uniform depth the
intensity of gravity is substantially the same as on continental plains.
Till Hecker's determinations were made, there was no assurance that this
was the case. Tlis results shoAv that the greater volume of continents is
compensated by their smaller density, and therefore that isostasy prevails
under the ocean as well as on those continental areas within wliich it ha.s
been tested. That improved methods of determining gravity at sea will
be evolved is scarcely to be doubted, but the most vital point at issue
seems to me to have been settled by Mr. Hecker's observations.^''

From his studies on deflection in the United States, Hayford got a
value of the ellipticity of the meridian which depends on the depth of
the level of isostatic compensation. If this is 120.9 kilometers, then the
reciprocal of the ellipticity so.found is 297.0 ± 0.5. One of the questions
still to be solved is whether the same value of the flattening will result
from similar surveys in other countries; or, in other words, whether the
depth of the level of compensation will be found constant. There seems
a possibility that it may vary with latitude,^^ and the data for the deter-
mination of this point already exist in the records of the geodetic surveys
of northern Europe, as Mr. 0. H. Tittmann informs me. Unfortunately
the subject of compensation has not there been methodically investigated.
This particular point is of the more interest since Mr. E. W. Brown's
recent researches on the moon^^ give for the flattening of the earth very
accordant values of about 1/294. Some means of reconciling so large a
difference must be found, and possibly it may be discovered in a variation
of the depth of compensation with latitude.

Hayford, Bowie, and Helmert all regard gravity anomalies as repre-
senting real loads, positive or negative. For this view there seem to be
two good reasons: this assumption strains to the utmost the Fratt-Hay-
ford hypothesis and it also lends itself readily to computation. Of
course, they do not deny that the anomalies might be due wholly or in
part to irregular distributions of density; but this explanation does not
appeal to them as it does to Mr. G. K. Gilbert*" and, as T shall explain
presently, to me also. The geodesists are at least ' on safe groimd.
Messrs. Hayford and Bowie conclude that the average excess or deficiency

^ See Helmert's luminous discusf5ion. Sltzungsber. k. Preuss. Akad. der Wlss., 1912,
Jan. to June, especially p. 309.

^ To my thinking, it would be very strange if the depth at the pole should be the
same as at the equator, for it is difficult to conceive that the physical conditions to
which compensation is due can have lieen tho same at the axis of rolalinn and the
extreme periphery.

•"""Science, vol. 40. 1914, p. .389. Vice-presidential address, B. A. A. S.

«U. S. Geol. Surv. Prof. Paper, 8.5-C, 1913.

DIRECT INVESTIGATIONS OF ISOSTASY 185

of matter is equivalent to that of a layer of rock about 570 feet or 174
meters in thickness with a density of 3.67.*^ As they point out, this
is small as compared with a safe working load for granite — only 660
])()un(ls per square incli against 1,200 for masonry — but the conditions
are very different. In masonry the principal joints or contacts are hori-
zontal. In nature joints are usually at an angle approaching 45° to the
horizon, while a dry stone wall with courses inclined at 45° would have
no sustaining power.*^

Discussion of Isostasy

This long review has been written with a view to deciding what geo-
logical results of geodetic research we are bound to accept. That ap-
proximate isostasy is a reality when areas of sufficient size are considered
seems to me to have been fully demonstrated. As for the unit area
within which it may l)c takcji for granted that isostasy is complete, opin-
ions differ, Mr. Helmert's estimate lieing far larger than Mr. Ilayford's.
This question will be settled to all intents and purposes within a few
years, at least so far as the United States is concerned ; for fresh stations
are being occupied each year, and before very long gravity maps will show
a mosaic of intersecting lines of zero anomaly, each closed area overlying
a column within which isostasy is complete. ^^ At present such informa-
tion as I have seems to indicate areas of from one square degree to several
square degrees.

Subject to a mean error, the center of inertia of the compensation lies
38 or 40 miles below the surface. If compensation is uniformly distrib-
uted, this center lies at a depth of 38 miles, while if it diminishes linearly
with depth it is 39 miles.

As yet the data are inadequate to decide between various hypotheses as
to the distribution of density in the active shell overlying the level of
isostatic compensation. This does not mean that the vertical distribution
of density is beyond investigation. Helmert's method of finding the
depth of this level is more promising in tliis respect than ITayford's, be-
cause it implies a determination of tlic \ci'tical couiponont of local attrac-

*i This density is adopted from Harkness. Mr. Helmert prefers 2.73, wlilch seems to
me nearer the truth for the surface. For the mean density down to 120 Isilometers I
believe a larger figure would be preferable, perhaps 2.80.

*= In his first paper Mr. Hayford adopted a lower estimate of the average sustaining
power. 'I'he mode of inference was not satisfactory and was ciilled in question by Mr.
Helmert.

^•''It may be well to remember that two columns, in each of which the anotualy has the
same sign, may slaiul in juxtjiposlticm and convi'y the impression of a unit area larger
than really subsists. Possibly some of the large areas pointed out by Helmert are thus
composite.

1 86 G. F. BECKER ISOSTASY AND RADIOACTIVITY

tiuu as well as the horizontal component. But Helmert's method is ap-
plicable at a comparatively small number of stations. Baron Roland
Eotvos's torsion balance** seems to afford a means of fixing the position
of locally attracting masses with some accuracy, since by it the radius of
curvature of the geoid is determinable; but this method is laborious in
the extreme, and many years must elapse before thorough surveys with
the torsion balance can be completed, even for a moderate number of
small areas.

Meantime the only recourse is to general reasoning, trial hypotheses,
and experiments on the properties of matter. To me it seems clear that
gravity anomalies must be of two classes, which I shall take the liberty
of calling real anomalies and pseudo-anomalies, the latter being due to
irregular distributions of density and not affecting the real load per unit
area at the level of isostatic compensation, while the real anomalies rep-
resent real differences in load at that level.

Areas of denudation and of deposition would seem to represent, at least
in part, what I have called real anomalies, for the removal of matter from
the outer surface of a column must reduce the pressure at its base, and
vice versa. But Messrs. Hayford and Bowie find it impossible to trace
any relation between the distribution of gravity anomalies and erosion or
sedimentation. This suggests that the effects of this actual transfer of
matter are masked by the effects of irregular distributions of density or
that the real anomalies are relatively small.

As for the pseudo-anomalies, we know for a certainty that the distribu-
tion of densities in horizontal directions at the earth's surface is very
variable, while the exposures in deep wells or in deep cuts, such as the-
Grand Canyon of the Colorado, give no evidence that heterogeneity di-
minishes with depth. On the contrary, the existence and abundance of
dikes, sills, laccoliths, and batholiths make it highly improbable that
homogeneity, or even a gradual and regular increase of density, prevails
at any level above the deeper volcanic foci. Differences in density as-
cribable to mineral composition are not the only cause of these pseudo-
anomalies. It is well kno'WTi that the thermometric gradient varies
greatly with the locality and in a seemingly capricious manner. Of
course, this distribution of temperature also affects density. Voids, too,
give rise to differences in density, and these, whether as geodes or as
joints, may be sparsely scattered or closely grouped. With the assistance
of Mr. A. F. Melcher, I have recently shown that the volume of a column
or stratum of rock may incroaso tlirougli cvushing by an nnimint the

** See Helmert's memoir on gravity and the mass distribution of tlie earth. Encyc.
der Math. Wiss,, vols. 6, 1, 7, article 23.

DISCUSSION OF ISOSTASY 187

apparent maximum value of which is 6.73 per cent*" of the original
volume.

How far down voids can exist is not fully determine*!. Mr. Frank
Adams has subjected cylinders of granite with holes drilled in them to
pressures corresponding to a depth of 35 miles without completely closing
the apertures; hut, making allowance for time and heat, he limits his
conclusion to the statement that openings may be permanent at least as
far as .1 1 miles from the surface.*" Mr. P. W. Bridgman*^ has subjected
sealed hollow cylinders of glass to a pressure of 24,000 atmospheres with-
out measurable permanent distortion, but he feels no confidence that a
crystalline solid would behave in the same way as glass at a depth of 56
miles. He tells me that in his experiments on rock specimens provided
with drilled holes these closed not by plastic flow, but by crumbling of
the walls. Since Mr. Bridgman can command a pressure of 40,000 at-
mospheres, corresponding to a depth of over 90 miles, there is no doubt
that more information is in store for us.

Pseudo-anomalies then certainly exist; indeed they seem of the order
of magnitude of the observed or apparent anomalies, namely, ± 0.017;
for, as was shown ahove, even tlie largest gravity anomaly observed in the
United States, 0.095, could bo accounted for by the presence of a batho-
lith less than 9 miles in diameter. But the gravity anomalies when con-
sidered with regard to sign have a mean value of 0.000, just as would be
the case were there only pseudo-anomalies and were isostatic compensa-
tion perfect at about 120 kilometers. It is barely possible that the real
anomalies are of the same order of magnitude as the pseudo-anomalies,
and that the mean value of each species with regard to sign is 0.000 ; but
were this the case I should expect greater local apparent anomalies than
Messrs. Hayford and Bowie have observed ; for there is little direct con-
nection between the pseudo-anomalies and tlie real ones, so that they
might be expected to reinforce one another at something like one-half of
the whole number of stations. But that the real anomalies and the
pseudo-anomalies should each average 0.000, though conceivable, is very
improbable. The oidy way I can see of reconciling the observations with
probability is to suppose that the real anomalies, though not zero, are so
small as compared with the pseudo-anomalies that their effect on the
average is insensible, or, in other words, that the real anomalies are small
quantities of the second order.

This conclusion, if conceded, means that the earth below the level of

<5.Tour. Wash. Acad. Sci., vol. 4. 1014, p. 420.
^''.Toiir. Geol., vol. 20, 1012, p. 07.
« Phil. Mag., vol. 24, 1012, p. 63.

XIV— BnLL. Geol. Soc. Am., Vol. 26, 1014

188 G. F. BECKER ISOSTASY AND RADIOACTIVITY

isostatic compensation has cooled only to a trifling extent, or that it is
there nearly in a state of ease, although since it is solid and has cooled
somewhat it must also be to some extent in a state of elastic strain. As
a matter of course, solid flow does not supervene until a mass of matter
has been strained to its elastic limit, and in spite of the flow such a mass
retains the maximum strain it is capable of enduring.*^

From the preceding discussion my main conclusion is that the real
differences in load per unit area at the level of isostatic compensation are
very small, not merely compared with total gravity at the equator, but
small relatively to the apparent gravity anomalies at the surface, and that
therefore the amount of shrinkage or cooling which has taken place below
that level is also exceedingly small.

Note on Epeirogent

That approximate isostatic compensation exists in the outer shell of the
earth must be accepted as demonstrated by the geodesists. How to ac-
count for this very fundamental fact is a geological problem which is too
complex for full discussion here. In another paper I have endeavored to
prove that if the earth's surface had originally been a perfectly smooth
equipotential surface, uniform in all properties excepting only in con-
ductivity, the areas of low conductivity would undergo relative uplift be-
cause the material underlying them would cool more slowly and would
ultimately develop into continents.*^ These would be subject to great
pressure by the more rapid contraction of the surrounding areas and
ultimately, for a sufficient temperature difference, to systematic Assuring.

So soon as the oceans came into existence and erosion began, the super-

** This strain, however, is probably smaller than is indicated by ordinary, brief experi-
ments on the strength of materials. After-effects appear to be small quantities of the
second order.

*" Areas of low condtictivity will also be areas of low diffusivity, provided that either
is the only constant subject to variation. The superficial temperature gradient for a
globe of very large radius, (clv/(lx)<,, may be expressed thus :

where V is the initial surface temperature, v the initial temperature gradient, and k the
diffusivity, or li/c, the conductivity divided by the thermal capacity. Now the heat
emitted is

so that if the diffusivity is constant the emission is simply proportional to the con-
ductivity, while if the thermal capacty is constant the emission increases with the dif-
fusivity. The values of n are more nearly constant than those of k or of k See Proc.
Nat. Acad. Sci., vol. i, 1915, p. 81. In preparing this the paper cited, I misplaced the
decimal point in the coefficient of expansion of typical rock ; an error affecting some of
the conclusions though not the main thesis. These will be corrected in the Proceedings.

NOTE ON EPEIROGENY 189

ficial transfer of material combined with a deep-seated solid flow in the
nature of an undertow would establish a system analogous to incipient
convective circulation in a mass of hyperviscous liquid. Such an un-
equally heated globe reduces to a species of heat engine. The outer layer
down to about the level of isostatic compensation takes in heat energy of
very high temperature, discharging it at little above zero, while a part
of the energy thus rendered available is converted into the mechanical
work implied in uplift (partly balanced by erosion) rupture and plica-
tion of the continents. The prominence of the continents above sea-
bottom indicates that the mean density of the subcontinental columns of
rock down to the level of compensation is lower than the density of the
suboceanic columns. This difference might be due to a moderate excess
in the proportion of voids beneath the continents (about 3 per cent), or
to an excess in mean temperature (some hundreds of degrees), or to any
appropriate combination of the two causes. The general features of the
dynamical system resulting in isostasy thus become intelligible if the one
simple postulate of non-uniform conductivity he accepted.-"

Eecent Advances in EADiOLoay

Only a few years since one of the most remarkable features of radiology
was the extreme simplicity of the known relations between the elements
of the uranium-radium group. It was known that after a moderate time
an equilibrium must be established between the various members of this
group, since each member could decay only as fast as it was generated,
and the law of decay was considered as absolutely established. This law
for a single element is expressed by

where I„ is the initial intensity of radiation I, the intensity at time
t and X is the radioactive constant. Many experiments had been made
to ascertain whether the value of A was modified, for instance, by high
temperature or high pressure; but no evidence of variability was dis-
covered then and, for that matter, none has been detected up to the
present time. So confident have radiologists been of the constancy of A
that they have not hesitated to extrapolate the law of decay, verified for
a year or two, over millions or thousands of millions of years.

When the law of decay had been established and the a particles had
been identified with helium, it became practicable In compute the Jimonrii

"^ Itplvin discussed the restoration of mechanical energy from an unequally heated
space. Phil. Mag., vol. 5, 1853, p. 102.

190 G. F. BECKER ISOSTASY AND RADIOACTIVITY

of helium Avliieh would escape from a system in equilibrium in a given
time. Then, after it had been shown by Mr. Strutt that some minerals,
notably zircon, retain at least most of the helium developed in them,
the time within whicli this helium could be evolved could be calculated
and Avas supposed to give an inferior limit for the age of the crystal.®^
Similarly, after Mr. Boltwood had shown it probable that lead is a stable
end product of the decay of radioactive substances, he suggested that the
Ph/lJ ratio would serve as a means of determining the age of plumlufe-
rous uraninites.

These interesting and perfectly legitimate efforts, however, led to diffi-
culties of which more hereafter.

Largely through researches in radiology, several investigators, chief
among them Sir Ernest Eutherford, have developed new ideas of the
structure of atoms, and indeed of the nature of the chemical elements.

It is Avell known that the Periodic Table of Mendeleef, arranged in the
order of the atomic weights of the elements, has been of great service to
chemistry and led in the hands of its inventor to the prediction of new
elements, which were duly discovered; yet the table was empirical and
exhibited puzzling irregularities. In recent years it has been given a
new and more satisfactory inteip relation, originating with Mr. A. van
den Broek,^^ who arranges the elements according to the number of
positive electric charges on the nucleus of the atom as conceived by
Rutherford. These charges advance by units from 1, the so-called
"atomic number" of hydrogen, to 92, the atomic number of uraniuin.
To eacli atomic number is supposed to belong an element (or possibly
a grou]) of elements), and only three or four gaps in the series now.
remain to be filled by discoveries.

Now comes the astounding feature of the subject. It has been defi-
nitely discovered bv ^fr. Soddv, Sir Ernest Eutherford, and others that
a single atomic number may be borne by each of several substances which
may have different atomic weights and, in the case of radioactive sub-
stances, different stabilities, but which are inseparable by ordinary chem-
ical or physical properties. They display the same chemical reactions,
the same electrochemical behavior, the same spectrum, the same volatility.
It would appear, according to Eutherford, that the charge on the nucleus
is the fundamental constant which determines the physical and chemical
properties of the atom.^^ Soddy calls the members of a group of elements

^1 Joly and Rutherford have devised a means of estimating the age of rocks from the
pleochroic halos in mica foils, these halos being due to radloactivitv. Phil. Mag., vol. 2.5,
ini3, p. 644.

M Nature, vol. 92, lOl."?. pp. ."^72 and 476.

°3 Nature, vol. 92, 191.S, p. 423, and Phil. Mag., vol. 27, 1914, p. 488.

RECENT ADVANCES IN RADIOLOGY 191

bearing a single atomic number, and occupying therefore a single place
in the periodic table, "isotopes." There has not been time as yet for
exhaustive investigation, but the only means which has yet been found
adequate to a separation of isotopes is diffusion (neon and metaneon),
while Sir J. J. Thomson's new positive ray method of gas analysis and
atomic weight determinations make it possible to distinguish isotopes
from one another. It is needless to say that other methods are being

sought.

Among the radioactive substances, or "radiants," as Mr. Eve^* calls
them, 34 elements have been discovered; but the study of their isotopic
relations reduces them to a much smaller number of groups, about 10
in all.^^ Representatives of five of these groups have long been known
(IT, Th, Bi, Pb, Tl), while the remainder have been discovered through
radioactive researches. Lead is isotopic with Eadium B, Thorium B.
Actinium B, and Radium I), while Radium itself is isotopic with Meso-
thorium I, Thorium X, and Actinium X.^^

Since the chemical reactions and, in great part at least, the physical
properties of isotopic elements are indistinguishable, it is very evideni;
that in nature they must be close companions. It is well known to all
of us that natural minerals are, as a rule, very impure, or that even great
chemical differences do not preclude inclusions in crystals or ])revent the
simultaneous crystallization of different substances. Hence it is to })e
expected that isotopic elements should l)e associated in radioactive min-
erals; for example, mesothorimn I with radium. But the period of
mesothorium I is several hundred times shorter than that of radium;
and, according to Mr. Soddy, a preparation containing 99 per cent
radium, together with 1 per cent of mesothorium I, is no less than four
times as radioactive as pure radium.^^ Yet being isotopes, radium and
mesothorium I are absolutely identical from a chemical point of view
and can not be separated. Hence there is no practicable means of ascer-
taining whether or not the helium found, say, in a zircon is derived
from mesothorium I or from radium.

Similarly lead or an isotope of lead may be derived from niem1)ers of
the radium series, the actinium series, or the thorium series. Only an
atomic weight determination of the lead would indicate its origin, and

■>» See his very readable, and of course authoritative, at'connt "f recent researches on
atomic structure in Science, vol. 40, 1914, p. 115.

"• F. Soddy, the chemistry of the radio elcnients, part 1, li»ll, :iii<l i>Mrl 'J, 1014. Much
of what follows Is taken from these admirable mcniographs.

"■The atomic number of lead Is 82 and that of uranium Is 92. Elements of the atomic
numbers 85, 87 seem not to have been found as yet. Mr. Soddy puts actinium In the
place whose atomic number should be 89.

WF. Soddy, op. clt., part 1, p. G9.

192 G. F. BECKER ISOSTASY AND RADIOACTIVITY

this origin is likely to be at least twofold. As Mr. Joly points out/'*
normal lead, with an atomic weight of 207, might be regarded as a mix-
ture of uranium-derived lead, with an atomic weight of 206, and of
thorium-derived lead, with an atomic weight of 208. Messrs. T. W.
Richards and M. E. Lambert have made comparative atomic weight
determinations of lead from five radioactive deposits and of common
lead, getting from the lead of a North Carolina uraninite deposit 20G.40^^
and for common lead 207.15. As they remark, "The result is amazing."
The various samples were treated exactly alike; protracted purification
had no effect on the atomic weight of any sample and no difference could
be detected in the spectra.®"

Isotopism seems to be established in principle. So far as I can see,
it precludes age determinations in minerals, even if the radioactive con-
stant A has undergone no change since a given mineral crystallized.
Isotopism also sufficiently explains the very wide differences in the ages
indicated for different crystals.

Ever since the earliest attempts to determine the age of minerals by
radiological means it has been observed that the agreement between dif-
ferent specimens of approximately equal geological age, or even between
specimens from the same deposit, was extremely poor. In the case of
helium this was explicable by the escape of a portion of the gas. Changes
in the lead-uranium ratio were less easily explained, since a variety of
lead compounds and uranium compounds are very insoluble. I pointed
out®^ that Boltwood's method gave ages for the minerals of Barringer
Hill varying from 1,671,000,000 years to 11,470,000,000 years, and more
recently Mr. F. Zamlionini'''^ has shown that the lead-uranium ratios, of
minerals from the neighborhood of Christiania indicate ages varying
between 41,000,000 years and 17,302,000,000 years. Because Brogger's
observations showed that galena in many cases crystallizes during "the
principal phase of pneumatolitic minerals," I inferred that lead minerals
were occluded in the uraninite.

Similar variations occur in the helium-uranium ratio and possibly also
for a similar reason. Helium received its name because it is a promi-
nent constituent of the sun, and it is difficult to suppose that it was not
also one of the original constituents of the earth. Mr. Strutt found that

^Science Progress, July. 1914, p. 52.

6»Tlie 1914 atomic weights are U = 238.5. He = 3.99 ; so that U — 8He = 206.6, cor-
responding almost precisely to Richards's 206.4.

*>Jour. Amer. Chem. Soc, vol. 36, 1914, p. 87. It is well to note that similar investi-
gations have been made in the Harvard Laboratory ou other elements — notably copper,
silver, iron, sodium, and chlorine — which gave constant atomic weights, irrespective of
their source. One of the irons was from a meteorite.

«Bull. Geol. Soc. Am., vol. 19, 1908, p. 134.

•2AttI. Accad. LIncei, vol. 20, part 2, 1911, p. 131.

RECENT ADVANCES IN RADIOLOGY 193

it exists in some beryls from which radium is absent. More recently
Mr. A. Piutti*'^ has examined 26 glucinum minerals which were not radio-
active, though they contained helium. The amount of this gas varied in
the same locality and appeared to bear no relation to the age of the
crystals. Helium also occurs in large quantities in mineral springs.
Messrs. Charles Moureu and A. Lepape found that the Carnot spring at
Santenay (Cote-d^Or) gives out no less than 17,845 liters of helium an-
nually.'^'' Now, according to Eutherford,^® 1 gram of radium in radio-
active equilibrium yields 158 cubic millimeters of helium annually. It
follows that if the helium of this spring is set free by radium there must
be present no less than 113,000 kilograms of radium. The Cesar spring
at Nevis (Allier) yields far more helium — 33,990 liters a year. The
French physicists conclude with ample reason that this helium is "fossil,"
or that it has been stored up for an indefinite time and is not a nascent
product of radioactivity.

All attempts to determine age by radiological methods assume that the
radioactive constant. A, is truly constant and finite; but, although no one
has yet succeeded in proving its variability, there are very serious doubts
about the matter. From the dawn of science philosophical investigators
have had in mind something corresponding to Eoger Bacon's protyl or
Kant's Urstofi:. Lavoisier was well aware of the existence of organic
radicles, gi-oups of atoms known to be composite, but behaving like ele-
ments. Ammonium and cyanogen are familiar inorganic examples of
complex bodies which take the place of supposedly elemental substances,-
while if complex substances may behave as elements, substances sup-
posedly elemental may be complex. The protylic idea underlay Front's
hypothesis and Mendeleef's periodic table; Dmnas also boldly asserted
his belief in the transmutability of the so-called elements. Astronomical
"observations indicate an increasing complexity in composition during the
evolution of stars. John Herschel thought that atoms bore the unmis-
takable stamp of a "manufactured article." In 1873 Mr, F. W. Clarke
suggested the evolution of one element from another. In 1904 Sir J. J.
Thomson asserted that as the universe gets older elements of higher and
higher atomic weight may be expected to appear. Finally, by showing
that many elements may be made to evolve helium and all elements
identical coi'puscles or electrons, the radiologists have prepared the way
for a greatly simplified conception of matter.

Now, if there are any circumstances in which a radioactive substance
is stable, A must become zero; and if we could reproduce sueli circum-

<»Attl. Accad. LIncel. vol. 22, part 1, 1913, p. 140.

•"C'omptes Keudus, Purls, vol. 155, 1912, p. 107.

"^ Had. substances and tbelr radiations, 1913, p. 5GU.

194 G. F. BECKER ISOSTASY AND RADIOACTIVITY

stances, it would be possible to manufacture synthetic radioactive sub-
stances. This. has not been accomplished, but I venture to say that it is
an achievement which would cause little surprise, though much admira-
tion. Suppose that ammonium had recently been discovered and proved
to consist of hydrogen and nitrogen; would any one doubt that the
synthesis of ammonium would eventually be effected?

Mr. Barrel prior to 1906 suggested to Sir Ernest Eutherford that the
gradual building up of the heavy and more complex atoms of matter may
be slowly taking place in the interior of the earth.*"^ In 1908 I pointed
out that the bounds of legitimate hypothesis are not transgressed by sup-
posing that at the consistentior status the surplus energy of aqueo-igneous
fusion was potentialized by the formation of uranium. In 1909 Mr.
Arrhenius expressed his opinion''^ that at higher temperatures the process
uf the evolution of heat by radium must take place in the inverse direc-
tion under consumption of this inconceivable amount of energy. Mr.
Joly regards the mode of origin of uranium and thorium as question-
able.*^" Mr. F. C. S. Schiller,''^ Mr. Leigh Fermor,^« and Mr. Arthur
Holmes'^ all consider it doubtful whether radioactive transformations
can take place at very high temperatures and pressures.

Thus the constancy of A or the uniformity of the disintegration of
radioactive substances is contrary to analogy and by no means generally
conceded. These substances are more endothermic than any others
known, and if their synthesis is possible it must be under extreme condi-
tions of temperature and pressure, such as have not yet been realized in
laboratories.'^^

"8 Radioactive transformations, 1906, p. 194.

8' Tlie life of the universe, vol. 2, 1909, p. 236. This is a translation. I do not know
the date of the original.

•^ Science Progress, July, 1914, p. 51.

«» Nature, vol. 91, 1913, p. 424.

71 Ibid., p. 476.

''^ Science Progress, July, 1914.

'2 The sun is not known to contain uranium. Rowland found none. In 1908 Mr. P. G.
Nutting was good enough to compare for me Exner and Haschek's table of the spectrum
of uranium with a 30-foot reproduction of the solar spectrum, but found no evidence of
its existence. In 1911 Mr. B. Hasselberg made a very elaborate investigation of the
spectrum of uranium and failed to identify any of its lines in the solar spectrum. Kgl.
Soc. Vetensk. Akad. Handl., vol. 45, 1911, No. 45. Mr. F. VV. Dyson has discussed sis
lines in the chromosphere which might be due to radium but coincide with lines of
other elements. The identitlcation seems to me unsatisfactory. Astr. Nachr., vol. 192,
1912, No. 4589. Mr. H. Gieljeler has apparently identified radium, uranium, and radium
emanation in Nova Gemiuorum 2. His conclusion is indorsed by Mr. F. Kiistner. .\str.
Nachr., vol. 191, 1912, No. 4582. Like the earth, the nun can not owe all of the heat it
radiates to radioactivity, and Sir B. Rutherford states that "if the sun consisted entirely
of uranium in equilibrium with its products, the generation of heat due to active matter
would only be about one-fourth of the total heat lost by radiation."' He suggests that
some of it may be due to the atomic disintegration of ordinary elements at the high
solar temperature. Op. clt„ p. 656.

RECENT ADVANCES IN RADIOLOGY 195

In the present state of knowledge, estimates of tlie age of minerals
founded on radioactivity can not command confidence. But since the
time element enters in a most pronounced manner into all radiological
processes, this science may eventually develop methods of age determina-
tion which will be a boon to geologists.

On the Earth's Eadiation

During the past few years many determinations of the radioactivity of
rocks and meteorites have been made by various analysts and the activity
of thorium minerals has been determined. New determinations have also
been made of the calorific eifect of radium and of thorium. Some six
years ago, while I was preparing a paper for this Society on the relations
of radioactivity to geology, the best available average content in radium
of surface rock was 1.4 X 10~^- grams radium per gram of rock as deter-
mined by Mr. Strutt, and the heating effect of radium was believed to be
about 100 gram calories per gram of radium per hour, this value having
been found by Madame Curie.

In 1913 Kutherford concluded that the amount of radium per gram of
surface rock was about 2 X 10"^-, and that it is accompanied by 1.3 X
10~5 grams of thorium. The heating effect of radium as determined by
St. Meyer and Hess and adopted by Rutherford is 133 gram calories per
gram per hour, while Pegram and Webb find that one gram of thorium
in equilibrium with its products gives 3.4 X 10"^ calories per hour. With
these data and taking the average density of surface rocks at 2.7, Ruther-
ford from the equilibrium theory" finds the heating effect of the uranium
present in 1 c. c. of rock 11 X 10~® calories per annum and of the thorium
8 X 10"^ calories per annum.'^ The sum is 19 X 10"^. The origin and
relations of actinium are still midetermined, and it is possible but not
certain that a further addition should be made for the heating effect of
this substance.

Still more recent determinations by Mr. Arthur Holmes''^ indicate that

^» A somewhat puzzling anomaly iu the behavior of certain radioactive minerals has
Just been explained by Messrs. S. C. Lind and C. K. Whittimore in a suggestive manner.
It has been known for some years that autunite and some other secondary uranium
minerals gave U/Ka ratios which did not accord with the theory of radioactive equilib-
rium. XAnd and Wliiltimore found that specimens of carnolite showed a similar abnor
mal behavior w Ikmi llu- samples lesU'd were small, but that when the samples rei)resfUted
large lots of ore the IJ/Ua ratios were normal. Tlu>y infer that radium is in some cases
transposed within a deposit giving rise to' local ineiiualities which are etpiali/ed by mix-
ing large (luiuitities of ore. It Is thus apparent that the equilibrium theory has with-
stood successfully a very severe lest. The possibility of local inequalities even in the
radium content of rocks should be borne in mind. .Jour. Amer. I'hem. Soc, vol. 30, 1914,
p. -JOdO.

" Uadioactive substances and their radiation, l'J13, p. 650.

"" Science Progress, July, li)14, p. 15.

196 G. F. BECKER ISOSTASY AND RADIOACTIVITY

Eutherford's estimate for the amoimt of radium in rocks is somewhat too
low. Holmes finds for the radium in acid rocks no less than 2.8 X 10~^-,
but the selection of the best average value is complicated by the fact that
the radium content of acid or persilicic rocks is a maximum. For medio-
.silicic, subsilicic, and ultra-subsilicic rocks respectively Holmes gets 2.45,
U.85, and 0.51 all multiplied by 10~^-. It is almost certain that radio-
activity is confined to a superficial shell of the earth only a few miles in
thickness/^ and in such a shell persilicic and mediosilicie rocks prepon-
derate, so that with his data 2.5 X 10~^- would be nearer the truth than
2 X 10-12.

I shall adopt the lower value for a reason which at first sight seems
strange. On the hypothesis that all of the heat emitted by the earth is
due to radioactivity, the higher the surface value of radioactivity the
smaller will be the earth's internal temperature. '^^

Suppose the highly artificial case of a globe of uniform ordinary tem-
perature, say 10°, provided suddenly with a uniform layer of radioactive
material just sufficient to supply the amount of heat now escaping. Then
assuming (as indicated by the half value period of uranium) that the
supply of heat is substantially imdiminished for a couple of thousand
million years, it is easy to compute the distribution of temperature for
any epoch. Rutherford's'^ estimate, given above, of the heat developed
by radioactivity in surface rocks, when expressed in c. g. s. units, is equiv-
alent to 6 X 10"^^ calories per cubic centimeter per second. I shall call
this constant q. The conductivity,'^ h, Eutherford puts at .004, while
for the observed gradient at the surface he adopts 1° C. for each 32
meters, or .00031° C. per centimeter. If this gradient is denoted by
{dv/dx)o and if s is the thickness of the layer of uniform radioactive
matter which will maintain the gradient

\dx) o

Substituting the numerical data cited in c. g. s. units gives

s = 20.7 X 10^ em. = 20.7 kilom.

'8 That aU of the heat emitted by the earth might be due to a relative thin layer of
surface rock seems to have been suggested independeutly by C. Liebenow, Phys. Zeitsch.,
vol. 5, 1904, p. 625, and by Rutherford, Radio-activity, I'd ed., 1905, p. 644.

'''' See the value of Vm below. ,

■'^ Radioactive substances and their radiations, 1913, p. 650.

™ Mr. H. H. Poole concludes from experiments on granite and basalt "that for tem-
peratures up to 500° or 000" C. the conductivity of the earth's crust may be taken at
about 0.004 without risk of serious error unless the conductivity is sensibly affected by
the large pressures involved." Phil. Mag., vol. 27, 1914, p. 58.

THE earth's radiation 197

With s given the excess of temperature, v, at any distance x from the
surface is*°

_ gx ( x\

so that at the bottom of the radioactive stratum ; that is, for x = s; the
maximum temperature is

""- 2A- ^ k' ' 2g \dx)o ' 2q

But for the elevation of melting point by pressure, therefore, the maxi-
mum temperature developed by radioactivity in the hypothetical earth
would about suffice to melt lead. Observe that for a given gradient v„,
is inversely proportional to q.

The hot stratum would somewhat gradually warm up the underlying
mass, and it is worth the while to ascertain its effect at Mr. Hayford's
level of isostatic compensation, which lies at a depth of 121 kilometers.
If u is the distance of this level below the radioactive layer, about 99
kilometers, the temperature excess, v, in accordance with Fourier's law,
is given by

Here < is the diffusivity of the rock or the ratio of the conductivity to the
thermal capacity. For the Calton Hill trap this is .00786 in c. g. s. units,
or per year and square meter « = 24.8037. If v = vy2, or 161°, so
that Hayford's level acquires half the temperature excess of the radio-
active shell, then

= .4769 or i = 434 X 10' years.

2 }/ Kt

Thus it appears that heat traverses a layer of rock a hundred kilometers
in thickness with extreme slowness.

It does not seem to me that on such an earth as that just considered
there would be any geology. No evident source of energy is available to
bring about upheaval, subsidence, or vulcanism, and therefore baseleveling
would obliterate the continents.

On the other hand, as is pointed out above, a superficial shell (»t' a cool-
ing earth, extending from the surface down to the level of isostatic com-

^ Proof of this pquatlon, established Independently by Messrs. R. .T. Strutt and Jobaun
Koeulgsberger, may be found In Bull. Geol. Soc. Am., vol. 19, 1908, p. 137.

198 G. P. BECKER ISOSTASY AND RADIOACTIVITY

pensation, may be considered as a heat engine. In such an earth there
is abundant energy available for geological processes, only a portion of
which is dependent on the sun.

Sir Ernest Eutherford, after giving the maximum temperature due to
a layer of uniform radioactive matter at, in roimd numbers, 300° C,
continues : "This maximum temperature seems too small to fit in with
the facts, for there is reason to believe that a temperature of about 1,300°
exists some distance below the surface."^^ He goes on to show that by a
logarithmic distribution of the radioactive matter an internal tempera-
ture excess just double that due to a homogeneous layer may be attained,
though only at a great depth ; but even in that case there remain at least
600° or 700° of temperature unaccounted for. It is clear that if the
earth at some distance below the surface is hotter than it would be if all
the emission were due U> radioactivity, a part of the gradient at the sur-
face must be due to some distinct cause, which can hardly be other than
an initial excess of temperature, and consequently the shell of radioactive
matter must be thinner than 21 kilometers.

Since the conduction of heat out of the earth complies with Fourier's
law, no matter what the origin of that heat may be, the superficial tem-
perature gradient is the sum of the gradients due to several causes. Of
these there appear to be three only, namely, an initial high temperature of
the exterior shell, an original temperature gradient due to the rise with
pressure of the temperature of consolidation,^- and exothermic transfor-
mations, including radioactivity. The evidence that the external portion
of the globe has been liquid to a considerable depth is well known and
Kelvin's summary of it has already been cited. Now, the initial surface
temperature was determined by the nature of the rocks composing the
original outer shell, and these must have been rhyolites, trachytes, and
andesites, in the main of holocrystalline texture. The temperature
gradient must also have been influenced by the composition of the rocks.
At the surface the temperature in question can not have differed much
from 1,300°, which is only about a hundred degrees higher than the
melting point of the more fusible basalt or diabase. The initial gradient
must have been less than the gradient of Mr. Barus's diabase melting-
point curve, and I have given reasons elsewhere, based on the law of
density proposed by Legendre and adopted by Laplace,, for believing that
it intersected his line at about 40 miles frum the surface.^^ These reta-

il Op. cit., p. 652.

*- This gradient answers to the hypothesis that the fluid portion of the earth was in
convective equilibrium.

»3 SmithsoniaD Misc. Coll., vol. 56, 1910, No. 6, p. 17.

THE earth's radiation 199

tions are unaffected by any hypothesis as to the origin of the lieat; f(n-
even if all the heat had been due to atomic disintegration, the rocks could
not solidify until the temperature sank to their melting points at the
prevailing pressure.

Let Y be the initial surface temperature (1,300°) and let c be the
initial gradient, 300/63,710 degrees per meter.** Then the- present
superficial gradient is

(^'-•)=^L. + .+f

Vrfx/o V TT K t 1^

k Udv\ V 1 )

_k I fdv\ _
q I \r/,r/o

q \ \(l.e)o V K K V t )

so that if / is assumed s can be found, or vice versa. Rutherford gives
g at 19 gram calories per annum, and the conductivity A- T shall take as
that of the Calton Hill trap, .00415 in c. g. s. units, or per meter per
year, 13.096 X 10*^. For the present surface gradient my preference is
1° C. in 38 meters. Rutherford's l''/32" is a fair average of observed
values, but there are reasons*^ for selecting as normal the gradients in
undecomposed massive rocks in relatively level country rather than a
mere average of observations. Many influences tend to raise the gradient
abnormall}', while none, excepting the neighborhood of large bodies of
cold water and the escape of gas, are known to lower it.

With ^ =co and c = o the data I have chosen would give a maximum
value of the uniform radioactive shell, say, .5,,, = 18.14 kilometers, and
all of the emission would be due to radioactivity. For any other case —
that is, if only a part of the heat lost by the earth is of radioactive
origin — the thickness of the radioactive layer would be in kilometers

s = 14.893 - 101509/ i/T

111 a little table below will be found values of .« for / i-anging fnun
68 X 10^ years to 1,314 X 10*^ years. This latter portentous age is
chosen because it would seemingly satisfy even the requirements of the
uranium-lead ratios and because it gives s/s_,^ = 2/3, meaning that just
2/3 of the heat emitted is of radioactive origin. Tf this age is regarded
as a superior limit, then at least one-lliird of (lie surface gradient is due
to initial heat, and the maximum tempcraluic due to the radioactivity of

"•In oHuT worfls, (lip initial tPtTipr-raliirc oxcoss is (aknn as ."'.on" af a dopdi ri|iial lo
1 per cpnt of the partli's radius, or (!:?,710 mptpis.
w Smithsonian Misc. Coll., vol, 56, 1010, No. 6, p. 26.

200 G. F. BECKER ISOSTASY AND RADIOACTIVITY

a uniform shelP® is 106°. To be sure, the limit of s/s^^ chosen is an
arbitrar}^ one, but it will answer the purpose in view. Were three-fourths
of the heat emitted due to radioactivity, the age would be over 6,200 X
10^ years. Even so, initial heat would play an important part in the
earth's heat emission. Thus it appears that thermal equilibrium can not
have been attained by the earth as yet, and that however important
radioactivity may be, the earth must be considered as a cooling globe.
While these results are dependent on the choice of constants, those
selected can not be very erroneous, and it seems impossible to avoid the
conclusion that, even if the earth is 1,300,000,000 years old, something
like a third of the surface gradient, and therefore also approximately one-
third of the earth's emission, is due to initial heat, while the contribution
of radioactivity to the earth's internal temperature is hardly great enough
to account for hot springs.

That depth at which the excess of temperature curve most nearly
approaches the diabase melting-point curve I have called the eutectic
level, because a smaller heat increment will bring about fusion at this
level than at any other. For any age equal to or greater than 68 X 10^
years the eutectic level lies 70 miles or more below the radioactive layer,
and the temperature gradient at this level will be independent of q. It
can readily be proved^' that if .r^ is the distance of the eutectic level
from the surface the conditions stated above are satisfied by

- '- 1

V TT K t ■ • = £ •* * '

.01 /• r

r being the earth's radius and b the melting point of diabase at the sur-
face, or 1,170°, according to Barus. The values of x^ for each of the
ages is given in the table. For f = 68 X 10^, a\ = 121 kilometers, and
for t = 1,314 X 10^, .Ti = 300 kilometers.

^ If the radioactivity were to diminish linearly with depth, the total amount remain-
ing the same as in the uniform shell, activity would vanish at a depth, say. o- = 2s, and
at this depth the temperature would be four-thirds of that computed for the bottom of
the uniform shell. Thus redistribution in this sense would increase the value 106' to
141°. Bull. Geol. Soc. Am., vol. 19, 1908. p. 144. On the other hand if, following
Holmes, I had taken the Ra- content of surface rock at 2.5 X 10 ~'^, the temperature
of 106° would sink to 91°.

« Smithsonian Misc. Coll., vol. 56, 1910, No. 6, p. 24.

S/?m.

.1425

in kilom
121

.26

140

.43

180

.50

206

.59

254

.64

286

.6667

300

THE earth's radiation 201

.Agf. in kilom.

68 X W If 2.58

100 " 4.74

200 " 7.72

300 " 9.03

600 " 10.75

1,000 " 11.68

1,314 " 12.09

The second column gives the thickness of the active shell, the activity
being supposed constant, and the third column states the proportion of
the emitted heat which is due to radioactivity.

Mr. Hayford^s level of isostatic compensation lies at a depth of 120,900
meters, or, not to be meticulous, at 121 kilometers.^® Such compensation
at an eutectic level seems natural and comprehensible; but under that
interpretation the age of the earth, with the data now available, is only
68 X 10^ years, and it does not seem possible that any corrections in the
values of the constants should increase the a.ge thus determined to more
than 100 X 10^ years.''^ On the other hand, if the eutectic level is at

"^ Supplementary investigation of the figure of the earth and isostasy. Coast and
Geod. Surv., 1910.

^^ To avoid a possible misinterpretation, it may be expedient to refer to a difference
of opinion which has arisen between Mr. .loly and myself. In discussing the age of the
earth from the accumulation of sodium in the ocean, as first suggested in modern times
by Mr. .Toly, I made allowance for the continual diminution of the exposed area of
Archean and igneous rocks from which the sodium is ultimately derived. The computed
age came out about 70 X 10" years. (Smithsonian Misc. Coll., vol. 56, 1910, No. 6.)
In Science I'rogross for .luly, 1914, p. 4.5, Mr. Joly expresses his dissent from my view,
maintaining the uniformity of the sodium supply and referring to his paper of 1890 in
the Trans. R. Dublin Soc. for reasons. In that paper he stated that the possible
diminution in the area of feldspathic rocks "should undoubtedly lead us to widen the
margin we allow for error in our estimate of geological time ;" and he drew attention to
the fact that such analyses of ancient slates and modern silts as were at his comtnand
tended to show a decrease with increasing age of the content in alkalies. He neverthe-
less adhered to the hypothesis of uniformity seemingly because old sediments freshly
eroded give up a fresh portion of their sodium content. This, of course, is true. Sodium
extraction is a slow, perhaps asymptotic process. But ultimately the alkali all comes
from the Archean and igneous rocks, and if the source of supply wore cut off it would
gradually cease or approach zero. Suppose that the original feldspathic rocks had been
in some way protected from decomposition or denudation once for all at the beginning of
the Cambrian. Would the reworking of pre-Cambrian sediments still be yielding as much
sodium as is now derived from continental areas about one-fourth of the area of which
is occupied by ancient feldspathic rocks? Surely not. The supply could be kept up only
if decomposition were undiminished by a superjacent detrital layer. But every member
of this Society knows that at many points In the northern part of the continent a layer
of compact tnrf, only .3 or 4 inches thick, has been sufficient to preserve intact glacial
scratches and polish, while exposed areas of the same rocks in the same region have lost
both. In the south a coating of saprollte a score or two of feet in thickness seems like-
wise a complete protection against weathering. In short, I adhere to my opinion that
as the amount of sodium In the ocean increases the available continental supply of
Bodltim decreases.

202 G. F. BECKER ISOSTASY AND RADIOACTIVITY

300 kilometers from the surface, isostatic compensation takes place with-
out fusion — indeed, without any known cause; and this is not the whole
mj^stery, for it would seem that a shell no less than 180 kilometers in
thickness bounded by tlie eutectic level and Hayford's level must have
cooled many hundreds of degrees below its melting point without dis-
turbance of its isostatic equilibrium. I can not grasp such a situation.
It does not appear certain that on a globe so old as 1,300,000,000 years
there could be much more geology than on the purely radioactive earth
first discussed. In a cooling sphere the temperature at the eutectic level
sinks with the progress of time more and more below the temperature of
fusion. In a 68 X 10® year earth a rise in temperature of about 150°
would cause fusion, while in the 1,314 X 10® year earth an additional
600° would be needed to melt the rock at the eutectic level. It would
seem to me that as such a globe gTew old fusion would be a more and
more infrequent phenomenon, and that fusion would be more and more
rarely accompanied by effusion. It is even questionable whether any
eruptions could occur on a globe in wliich the eutectic level is 300 kilo-
meters beneath the surface.

Conclusions

The geodetic evidence for isostasy is so manifold and so consistent as
to amount to proof. Observed anomalies appear due in large measure
to irreguar distributions of density, and I conclude that the variations
in the load per unit area at the level of compensation are very much
smaller than the surface anomalies, while beneath this level the strains
are probably small quantities of the second order.

Considered physically, the only interpretation I can put upon the
level of compensation is that it is the level of easiest fusion or of eutexia;
and, if so, at that level the tangent of the curve showing the temperature
of the earth as a function of depth is parallel to the curve representing
the melting point of the rock as a function of depth. Local fusion would
bring about compensation. Where, then, should we look for compensa-
tion, if not at the eutectic level ?

Independently of this physical interpretation, the two curves just
referred to can not be far apart at the compensation level, for otherwise
a thick shell underlying this level must have cooled through, a large
temperature interval and must have undergone strains inconsistent with
compensation.

Epeirogeny and orogeny may be explained as due to the conversion into
mechanical work of a part of the heat received by the outer shell of the

CONCLUSIONS 203

earth at the compensation level and emitted at a comparatively low tem-
perature by the outer surface of the globe. To account for such a mech-
anism it is sufficient to assume that conductivity of certain areas, destined
to be occupied by continents, was lower than that of the remaining sur-
face of the globe.

Very early in the history of radiology — the greatest achievement of
physics since the establishment of the second law of thermodynamics —
means were suggested for determining the ages of minerals. They seemed
plausible, but gave results agreeing very badly among themselves, and for
the most part many times as great as those deduced from study of the
earth as a cooling body or of the ocean as the depository of the sodium
extracted from continental rocks.

Eecent advances in the study of atomic structure, and especially the
discovery of isotopic elements — that is, different elements occupying the
same place in the periodic table but inseparable by ordinary chemical
means — render the uranium-helium ratio and the uranium-lead ratio
practically valueless for the determination of the age of minerals.

If it is granted that the compensation level is an eutectic level, and
this seems the only intelligible theory, the age of an earth heated both by
compression and by radioactivity can be computed.

Geodesists assert that the compensation level is between 110 and 140
kilometers from the surface. The smaller depth would correspond to an
age so small as to be unacceptable to geologists. For a depth of 121 kilo-
meters the age would be 68 X 10^ years and one-seventh of the heat
emitted would be due to radioactivity. For a depth of 1-10 kilometers the
age would be 100 X 10^ years and 26 per cent of the heat lost would be
ascribable to radioactivity. Greater depths of the compensation level
seem incompatible with slight strain beneath that level, and can not be
accepted from the point of view of this paper, but data are given for an
earth no less than 1,314 X 10^ years old corresponding to the hypothesis
that two-thirds of the heat emitted by the globe is due to radioactivity.

To some extent the results reached depend on the constants adopted,
but there is strong reason for believing these so nearly correct that a large
percentage change in the results is very improbable.

It appears, then, that the position of the level of compensation is in-
compatible with any immense age for the earth, while the discovery of
isotopic elements throws us back on means not involving the uranium-
helium or the uranium-lead ratios for the determination of this age. In
particular the age of a radioactive earth which is also initially hot may
be computed from Fourier's law of conduction as readily as if it were not

XV— Bull. Ckol. Sor. Am.. Vol. -JO. 1!»14

204 G. F. BECKER ISOSTASY AND RADIOACTIVITY

radioactive. There is even a possibility that radioactive energy has been
potentialized at the expense of energy of compression.^"

It has often been asserted that the discovery of radioactivity indefi-
nitely prolongs the probable age of the earth. To me it seems that the
determination of the level of compensation limits both the age of the earth
and the amount of radioactive matter in its outer shell.

"" Ascription of the heat of stellar bodies to compression originated with Kant in 1785,
not with Helmholtz in 1854. Cf. Bull. Oeol. Soc. Am., vol. 19, 1908, p. 130.

BULLETIN

OF THE

Geological Society of America

Volume 26 Number 2
JUNE, 1915

JOSEPH STANLEY. BROWN. EDITOR

PUBLISHED BY THE SOCIETY
MARCH, JUNE, SEPTEMBER, AND DECEMBER

CONTENTS

Pages

Diastrophic Importance of the Unconformity at the Base of the Berea

Grit m Ohio. By H. P. Gushing 205-216

Origin of the Red Beds of Western Wyoming. By E. B. Branson 21 7-230

Origin of Thick Gypsum and Salt Deposits. By E. B. Branson - 231-242

Length and Character of the Earliest Inter-Glacial Period. By

A.P.Coleman - 243-254

Obsidian from Hrafntinnuhryggur, Iceland : Its Lithophysae and Sur-
face Markings. By Fred. E. Wright 255-286

Post-Ordovician Deformation in the Saint Lawrence Valley, New

York. By George H. Chadwick 287-294

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Communications should be addressed to The Geological Society of America,
care of 420 11th Street N. W., Washington, D. C, or 77th Street and Central
Park, West, New York City.

Entered as second-class matter in the Post-Offlce at Washington, D. C,
under the Act of Congress of July 16, 1894

PRESS OF JDDD & DETWEILEB, INC., WASHINGTON, D. C.

BULL. GEOL. SOC. AM.

VOL. 26, 1914. PL. 8

FiGUKE 1. — West Wall of Bi;ooklyn Ciia.vxel

'I'he view is on the north side of the cut. On the right is sandstone at the track level..
On the left is Bedford shale, reaching 10 feet above the track level

FiouKE 2. — East Wall ok Buookly.n Channel

On south side of cut is shown steeply inclined contact of shale and sandstone in center
of view. Sandstone at track level on right and 30 feet of Bedford shale on left

EAST AND WEST WALLS OF BROOKLYN CHANNEL

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA
Vol. 26, pp. 205-216, PL. 8 JUNE 15, 1915

DIASTROPHIC IMPORTANCE OF THE UNCONFORMITY AT
THE BASE OF THE BEREA GRIT IN OHIO ^

BY H. P. GUSHING

{Presented before Ihe Society December SO, 1914)

CONTENTS

rage

I ntroduction 205

Description 20()

The Brooklyn channel 20f;

The underlying formations 208

Extent of the Berea sandstone • 20l>

Ohio Berea a non-marine formation 210

Uplift following the Bedford 210

Importance of the unconformity 211

Comparison with the Pottsville unconformity 21.3

Conclusion 215

Inteoduction

In 1874 J. S. Newberry made the following statements in the Ohio
reports :

"In most localities where the Bedford shale is exposed the upper surface is
\ery irregular, and it^ is evident that the formation has heen extensively
eroded by the agency which transported the beds of sand, now consolidated
into the Berea grit." -

"The best exposures of the entire thickness of the Bedford shale are on the
Black River below Elyria. ... It will also be noticed here that the upper
surface of the shale is very irregular, showing that the currents of water
which transported the sand — now the Berea sandstone — cut away the shale,
then a red clay, in broad and deep channels. As these were filled with sand,
the under surface of the sandstone is very uneven and its thickness variable." '

This imconformity, noted so long ago by Newberry, is wide-spread, and
has attracted the attention of all the more recent workers in the State.

» MannscHpt received by the Secretary of the Geological Society February 8, 1915.
*r,eol. Surv. Ohio, (ieol., vol. 2, p. 01.
=■ Ibid., p. 212, Geology of Lorain County.

(205)

206 H. p. GUSHING UNCONFORMITY AT BASE OF BEREA GRIT

Orton mentions it, and seems to have attributed no more importance to
it than did Newberry. Burroughs has described some phases of it in
Lorain County, Prosser has treated of it in the central and northern
parts of the State, and the writer has been familiar with it for many
years, and has long had a description of it as it occurs in Cuyahoga
County in a manuscript whose publication has been greatly delayed/ It
is an extremely obvious discordance, is at once noted in any good section,
and for several reasons the present seems an auspicious time to discuss its
significance.

Description

Unquestionably this unconformity is most prominent in the district
described by Burrows in Lorain County and westward, where the most
northwesterly outcrops of the formation in the State occur and where the
strike swerves from an east-west to a north-south direction along the east
side of the Cincinnati anticline. Here its type is of deep, sand-filled
channels cut out in the underlying shales. These reach an extreme depth
of from 150 to 175 feet, are fairly steep-sided, and have apparently a
width of but a few hundred feet, only from three to five times the depth.

East and south from this northwest angle the unconformity rapidly
loses this prominent character. Considerable channels are present in
Cuyahoga County, next east of Lorain, though much smaller than the
Lorain examples; but the general character of the contact is that of
rather slight irregularity, the surface of the shale being etched with
small, shallow channels wliich ai'c filled with sand. In general a thick-
ness of less than 10 feet is involved, and usually much less. The in-
stances described by Prosser from central Ohio seem all of this type.

The Brooklyn Channel

Perhaps the best exposure yet seen in illustration of the miconformity
is one on the southwest edge of Cleveland, first studied by the writer in
1907, soon after it had been developed by a deep cut made in construc-
tion of the Belt Line Railroad. A glance at the accompanying map,
figure 1, which is a reproduction of a small portion of the western mar-
gin of the Cleveland topographic sheet, will show the 840-foot contour
projecting northward in a long, narrow promontory, reaching out three-
fourths of a mile beyond its normal line. It forms a prominent cusp
which, as seen from the north, constitutes a bold and striking feature of

* .Tour. Geol.. vol. xix. pp. 655-659 ; vol. xx, pp. 585-604 ; voL xxii, pp. 766-771 ; Bull.
15, Geol. Surv. Ohio, 4th series.

BROOKLYN CHANNEL

207

the topography. The Belt Line makes a deep cut from west to east
squarely across this promontory, with the track level at about 800 feet
altitude. The section sho^\^l in the cut is sketched in figure 2. Midway
is a filled channel of Berea sandstone, whose deeper central portion is

Figure 1. — Portion of Clerelaml Quadrangle, showing Location of Brooklyn Channel

below the level of the road-bed, hence unexposed. The walls of the chan-
nel are of red Bedford shale. The east wall is steep, the inclination
being about 35 degrees, with the Bedford shale rising rapidly above the
base of the cut until it attains a height of 30 feet above the level of the

O FEET

FiciUKE 2. — Section of the Belt Line Railroad Cut
This cut Is across the Brooklyn Channel of Berea sandstone cut hi Bedford shale

road-bed. The west wall has a much more gentle inclination, only about
10 degrees; the Bedford rises much less rapidly from beneath and attains
a height of only 10 feet above the track at the west end of the cut. The
two reproduced photographs which form plate 8 show tliese two contacts,

208 H. p. CUSHIXG INCONFORMI'IY AT P.ASE OF BEREA GRIT

the cut being altogether too long to he compressed into a single view.
The Berea is below the track level for a distance of about one hundred
yards and likely attains there an additional thickness of from 15 to 20
feet; but as the exposures stand they show a channel, probably a stream
channel, cut into the shales to a depth of certainly over 30 feet, probably
oO feet, and with a width of some one hundred yards at the level of the
road-bed. The greater steepness of the east side indicates that the cur-
rent was cutting asrainst that bank. The sandstone in the channel is verv
unevenly bedded and the adjacent shale is disturbed, chiefly by a bending
do\^'n parallel to the slopes of the channel sides.

So far as known to me, this is the most easterly of the channels of good
size that has been discovered. "While by no means so large as some of
those farther west, it is of the same type and the excellent exposures
justify its lengthy description. Unfortunately today the showing is by
no means as good as it formerly was. The Bedford shale, especially in
its upper red portion, is an extraordinarily weak formation, crumbling
with great rapidity and becoming covered Avith vegetation in a single
season ; but the base of the Berea still shows as sharply as in 1908, when
photographed.

Elsewhere in the Cleveland vicinity the contact shows only minor
irregularities. The shale surface is repeatedly channeled, but the chan-
nels are small and shallow, and this is the general character of the contact
all across northern Ohio.

. The underlying Formations

Beneath the Berea is a thickness of many hundreds of feet of shales.
Directly beneath lies the Bedford shale, with a thickness of from 75 to
100 feet where fully developed. For the most part it is an exceedingly
weak, clay shale. In the western sections, those containing the channels,
the formation is mostly a red shale of this type which, when freshly ex-
posed, breaks down to a sticky, red clay in a very few days. In the basal
portions are some thin, harder bands of shale and an occasional thin band
of sandstone. In the Cleveland district the formation carries a 20-foot
sandstone lentil, the Euclid bluestone, in its basal portion; l)ut I know
of no channel which has cut dowai to the bluestone horizon. The blue-
stone has an interest from the standpoint of this paper, since it shows at
its base irregularity of the channel type, quite like that at the base of the
Berea, though on a much smaller scale. In the quarry floors of some of
the quarries at Euclid excellent illustrations of this are shown. It is an
interformational irregularity and due to contemporaneous erosion, with

UNDERLYING FORMATION 200

the change of conditions from mud to sand deposit; but it seems to me
of distinctly the same type as the channeling at the base of the Berea.

In central Ohio there are some sandy beds near the summit of the
Berea, so much so that there have been differences of opinion as to where
to place the line between the two. Prosser thinks these sandy beds have
been eroded away over areas of considerable extent prior to Berea deposi-
tion, and argues a time interval of considerable extent between the two
to account for this erosion. The writer is unfamiliar with those sections,
but in conversation with other geologists, who do know the region, ex-
pressed interpretations of the phenomena did not correspond with Pros-
ser's interpretation.

Below the Bedford lies the Cleveland shale, a black, slaty shale, which
today is a much more resistant formation than the Bedford ; but it
breaks down rapidly on exposure to the weather, when exposed in banks,
and certainly is not a formation of any particular resistance to erosion
as compared with ordinary sandstones and limestones. In the post-
glacial valleys of the small streams in northern Ohio an excellent idea of
the erosional resistance of this formation can be obtained. It comes into
the problem at all only because the deep channels of the northwest dis-
trict cut into it.

Beneath the Cleveland in the eastern sections lies the gray Chagrin
shale. It is weak, but the Berea erosion nowhere reaches it. West of
Cleveland a blackish shale, with occasional blue bands, lies beneath and
is a weaker rock than the typical Cleveland shale. The bottoms of the
deeper western channels are in this rock.

Extent of the Berea Sandstone

The Berea extends out of Ohio into Michigan on the north, Kentucky
on the south, and Pennsylvania on the east. In Michigan it is kno\\Ti
only on the east side of the Carboniferous basin and does not show in
outcrop. Lane, from study of the drill records, reports it as varying in
thickness from 40 to over 300 feet, as being thickest and coarsest on the
west, and then suddenly disappearing.^ In all probability this means
also the occurrence of channels similar to those on the northwest in Ohio,
perhaps somewhat deei)er, since the greatest known tliickness in Ohio
does not much exceed "iOO feet. Lane states that the Michigan Berea
forms a deposit along a shore facing east and running nearly north-
sduth, and this corresponds well to the Oliio conditions.

" Jour. Geol., vol. 18, p. 418.

210 H. p. GUSHING UNCONFORMITY AT BASE OF BEREA GRIT

Southward in Kentucky the Berea rapidly thins, becomes indistin-
guishable from the underlying Bedford, which also thins, and both dis-
appear before central Kentucky is reached, according to Foerste and
Morse.^ Either the Berea was not deposited so far south or else the de-
posits swerve to the east of the present erosion surface, so that their west-
ern edge is still under cover.

Traced into western Pennsylvania, the Berea is found to be the equiva-
lent of I. C. AATiite's Corry sandstone, at least in part. Whether it in-
cludes more than that and comprises the Cussewago sandstone and shale
also, as urged by Prosser, is quite likely.'

Xow the Corry sandstone in western Pennsylvania, notably at Corry,
carries a marine fauna, as White long ago sliowed. Eecently Girty has
published a faunal list from this formation.^ Evidently the Berea here
is, at least in its upper portion, a marine formation.

Ohio Berea a xon-marine Formation

In outcrop in Ohio certainly the entire Berea must be classed as non-
marine. It holds occasional fossil fishes, notably at Chagrin Falls, and
contains plant fragments in abundance in certain layers at many locali-
ties, but practically no other fossils. The plant fragments are in gen-
eral converted into coal, and layers with abundant plants often carry
clay lumps in the sand. The formation must be regarded as a continental
one, probably a delta deposit.

Uplift following the Bedford

The foregoing account enables us to picture the events which closed
Bedford and inaugurated Berea deposition. The Bedford is a marine
deposit, with the possible exception of its extreme upper portion. At its
close the land which lay to the north of the Bedford basin was given in-
creased altitude above sealevel, streams were invigorated and brought
down a plentiful sand supply in place of the fine muds of the Bedford.
The northwestern district was sufficiently far inland and of sufficient
altitude to enable the currents to channel deeply and efficiently. East
and south the sand was spread broadly over the low delta region, with
much minor channeling of the underlying surface, but no deep channels.
The sealevel was slowly rising, so that ultimately delta conditions pre-

8 Ohio Naturalist, vol. 9, p. 516.

7 Bull. 15, Geol. Surv. Ohio, pp. 375-377, 390-404.

s Annals N. Y. Acad. Sci., vol. 22, p. 303.

UPLIFT FOLLOWING THE BEDFORD 211

vailed over the channeled district, while marine conditions were brought
about in western Pennsylvania.

Importance of the Unconfokmity

Unlike many imconformities in horizontal rocks, that between the Bed-
ford and Berea is exceedingly plain. Evidence for it fails in few good
sections. But how much of a time gap is indicated by it?

The answer to this question is somewhat affected by two considerations,
for which there is little obtainable evidence one way or the other. Had
the underlying rocks become indurated during the interval between their
deposition and the beginning of Berea time, and if so how thoroughly ?
Did perhaps a long time gap intervene between the close of the Bedford
and the beginning of the Berea, a time during which the land lay quiet
at low altitude, experiencing neither erosion nor deposit?

Even with the present degree of induration the rocks which underlie
the Berea across Ohio are for the most part so weak that they afford little
resistance to currents of even weak erosive power. Many of the shale
banks along the stream courses even show rain-gulleying. This is espe-
cially true in the western district where the prominent channels occur.
They are chiefly cut out in soft red and blue shales, which are even less
resistant than a heavy clay soil would be, since they crumble on exposure.
The black shales beneath, those in which the bottoms of the deep chan-
nels are cut, are not greatly more resistant. They are weak rocks today.
The occasional thin sandstones which are cut out present a greater ob-
stacle on the supposition that they had so quickly attained their present
degree of induration, and it is on their evidence that Prosser chiefly bases
his conception of the importance of the unconformity. But if the time
gap was small, as we conceive it, it is certainly not illogical to hold tliat
it is unlikely that these sands had so quickly attained their present com-
[)actness. Tlie quotations from Newberry, with which this paper begins,
shows this to have been his view. When one considers the general condi-
tion ill wliicli many rocks of Tertiary age are found today, in districts
unaffected by orogenic or igiieous activity, the supposition seems not
unreasonable. But we may grant that the rocks had attained their pii-s-
ent <legree of indiii'at ion lid'occ Borca deposition began and yet not ma-
terially alTect our argument. We regard it as prol)at)le that induration
was not far advanced, because all other features of the break speak for a
very short time gaj). Jiut tlie present degree of indnration may be ad-
mitted and still not materially affect the force of llie argument.

The minoi' cliannclin" in the eastern region is likelv the result of scour

212 H. p. GUSHING UNCONFOR]MITY AT BASE OF BEREA GKIT

and fill action on a delta floodplain. The more prominent channels on
the northwest seem more like definite stream channels, yet their depth,
their varying direction (they trend all the way from north-south to east-
west), and the evidence of rapid filling suggest that they may be scour
channels also. But definiteness here is not necessary to the point v/hich
we wish to make, namely, that on either view the erosion stage indicated
is a very juvenile one and points to a very short time gap between the two
formations. If the process was one of scour and fill in soft muds, cur-
rents adequate to the transportation of quantities of coarse sand and of
complete removal of all finer material from it as it was deposited were
competent to do the work in a very short time. If the westerly channels
were cut by individual streams and the rocks had their present degree of
induration, the time required would be longer, several times longer; but
even then the character of the channels is indicative of a very immature
erosion stage. They are cut in weak rocks, mostly very weak. They are
not broad; in fact, when the nature of the banks is considered, they may
all be said to be very narrow. Their tops are all at the same geologic
horizon and their bottoms at quite different horizons, even in the same
restricted district. There is not even an approximation to gradation in
the channel beds when compared with one another. Between channels
there was no removal of material at all. The whole physiography be-
speaks immaturity of erosion stage. And it was, no doubt, this phase of
the subject which impressed ISTewberry so forcibly that he made no point
whatever of the break when he built up his Ohio section. In these weak
materials wide-spread baseleveling would have resulted from a long ero-
sion interval, and the stream beds at least would have been thoroughly
graded in a shorter interval; but there is no approximation, even to the
latter.

Precisely the same phenomena on a smaller scale are shown at the base
of the Euclid sandstone lentil in the basal Bedford shale. The sandstone
is argillaceous and of finer grain than the Berea; and though a shore
deposit, it is a marine one, even though the appearance of the sand badly
discouraged the marine fauna of the Bedford; yet the soft, underlying
shale is channeled in moderate fashion, and at the westerly margin of
the lens, in west Cleveland, sand-filled channels several feet in deptli
occur, with great disturbance of the underlying black muds. No one
calls this anything but contemporaneous erosion.

The Berea rests always on the Bedford. To us the most obvious and
most conclusive evidence in support of our view of the trifling character
of the Bedford-Berea break is the fact that all across Ohio, along a meas-
ured length of oiitcrop of about 300 miles, from the Ohio Eiver north to

IMPORTANCE OF THE UNCONFORMITY 213

the lake and then eastward to the Pennsylvania line, the Berea rests on
the Bedford shale. The Bedford is both a thin and a weak formation,
susceptible of easy and rapid erosion. It seldom exceeds 100 feet in
thickness and seldom falls below 50 feet, except along the channel bot-
toms in the northwest corner, in the deeper of which it is entirely cut
out. To believe in a considerable time gap between the two formations,
one is forced to believe that along this entire long line oscillation took
place, with no warping whatever. The land was either so low that no
erosion took place, and the channels seem to negative that, or else it was
so evenly uplifted that the same amount of erosion took place everywhere.
There is nowhere, so far as known to us, an oscillation involving so long
a line without some local warping being involved. We have had occa-
sion in the past ten years to study many of the unconformities within
the Paleozoic series in New York. Without exception, they are charac-
terized by the fact that the formation which follows the break rests on
underlying beds which vary in horizon from place to place. The oscilla-
tion has been always accompanied by gentle, very gentle, warping, and
the upwarped beds have been truncated by erosion before renewed deposit
took place. This is the one feature which they all have in common, and
the one feature unexplainable on any other theory than that of a pro-
tracted erosion interval between the two sets of deposits. It is wholly
lacking at the Berea base in Ohio. We are personally unable to conceive
of the possibility of an oscillation of the type, involving such a long line,
without the appearance of some warping, with ensuing truncation should
an erosion interval follow.

Comparison with the Pottsville TJnconfoumity

The break at the base of the Pottsville in Ohio furnishes an excellent
ilhistration of this ordinary type. It is a real break. It rests on the
gently truncated edges of several of the Waverly formations, as it is fol-
lowed across Ohio. In the Cliagrin A'alley, east of Cleveland, the Potts-
ville base is only 100 feet above the Berea summit and rests on the
()niiigc\ ille. Eastward other bed.s conie in. and when the Pennsylvania
line is reacheti the I'ottsville is some 3o0 feet above the Berea, the thick-
ness being a<l(!e(l, heij l)y l»e(|. in passing east. West I'loni the Chagrin
\'iilliy tlu! same thing takes place, and somewhat more rapidly than in
ihe otlier direction. Over most of northern Ohio the Pottsville rests on
various beds of the lloyalton i'orniation. West of the Cnyahoga tiie Potts-
ville-Berea interval is from .")<»() to I0() feet. \\\ the time lentral Ohio is
readied the entire Blaek Hand and Logan formations have come in and
the interval expanded to .something like 1,000 feel.

214 H. p. GUSHING UNCONFORMITY AT BASE OF BEREA GRIT

At the base of the Berea we utterly miss this sort of evidence. The
underlying horizon is unvarying. To be sure, when we pass out of Ohio
the Berea is found resting on the Chagrin formation, in the comities of
western Pennsylvania. To Ulrich and myself the Bedford absence there
seems a ease of overlap. It is absent because it was never deposited there,
the district lying without its basin. Prosser does not accept this view,
but holds, if I understand him correctly, that the Bedford disappears by
lateral gradation into beds which carry a Chemung fauna. The sections
are scattered and poor and the evidence incomplete either way; but to
the writer it seems a clear case of overlap. Along the Ohio-Pennsylvania
line there seems to have been a barrier formed between two separate
troughs of deposit. On the Pennsylvania side the EJiapp and Conewango
formations were laid down on the Chemmig, but did not get into Ohio to
any extent. On the Ohio side the Bedford was deposited, but failed to
pass over into Pennsylvania. Along the barrier both substantially fail
and the Berea lies on the Chagrin. It so lies not because of erosion of
the other formations, but because they were never deposited there.

It is frankly admitted that the above interpretation does not meet the
views of many geologists. It seems to us, however, that we may also
waive this and not greatly affect the force of our contention that the
uniform resting of the Berea on the thin and weak Bedford formation
ail across Ohio makes it exceedingly improbable that their contact can
mark a time interval of any particular import^ance.

Prosser has described a Berea-Bedford contact at Warner Hollow,
Ashtabula County, where the upper Bedford has been slightly crimipled
and also slightly faulted before Berea deposition began.'' He emphasizes
the locality as of exceptional importance in demonstrating a disconform-
ity, between the two formations. AVe can not see it in the same light.
The disturbance is exceedingly local and exceedingly small in amount.
The locality is not many miles west of the meridian along which the Bed-
ford disappears, hence near what we regard as its eastern shoreline. Very
trifling local causes could produce disturbances of this character in uncon-
solidated muds and sands. It seems to us to have no weight whatever in
comparison with the great general fact that the Berea base j^ractically
does not change horizon all across Ohio, but rests everywhere on the tliin
Bedford shale.

In Kentucky the Berea disappears by overlap. It may also be noted
that the Bedford is a partner in this transaction, the two both thinning
and pinching out together, letting the Sunbury black shale down on the

» Bull. 15, Geol. Surv. Ohio, pp. 312-315.

COMPARISON WITH POTTSVILLE UNCONFORMITY 215

Cleveland shale as contributing elements to the Chattanooga shale. This
does not seem to us indicative of any particular time gap between the
Berea and Bedford.

At the base of the Pottsville in northern Ohio precisely the same sort
of channeling of the underlying surface is observable as at the Berea base.
This seems to us a feature produced entirely subsequent to the general
long period of erosion which truncated the gently warped surface of the
Mississippian rocks before Pottsville deposition began. After the base-
leveling was complete the surface was channeled by the currents, which
transported the gravel and sand which constitute the basal Pottsville.
The channeling does not of itself suggest a time gap; it is the previous
warping and the truncation of the warped beds by long erosion, so that
the rock just under the Pottsville varies much in horizon across tlie
State, which demonstrates the unconformity and proclaims its impor-
tance. It is just this sort of evidence which absolutely fails in the case
of the Berea base.

Conclusion

The matter is here discussed and this view emphasized because of the
present tendency on the part of several geologists to draw the line be-
tween tlie Devonian and Mississippian at this Bedford-Berea horizon and
to quote the imconformity as evidence justifying the procedure. If this
were a m.ere local question affecting only Ohio and Michigan, I should
not have discussed it. I readily admit that, in so far as considerable
parts of tliose two States are concerned, this is perhaps the most con-
venient and easily recognizable horizon at which to draw this line. I
also willingly admit that it is a better place to draw it than at the base
(){' the Beilford shale, where it was placed by Orton and where there is no
break at all, so far as I can discover. But it would seem that this con-
venient line in Ohio is located at the expense of the geologists of Ken-
tucky, New York, and Pennsylvania, in which States it is far less easy
of recognition or else not recognizable at all. But this is a long ami in-
volved question, with many phases, and my purpose is simply to empha-
size one of these.

In ni;iny districts the line between the Devonian and Mississippian is
a confessedly difficult one to draw. Nowhere is this more true than in
Ohio, where difference of opinion cimcerning its proper location has long
prevailed and still prevails. Unless we are totally at fault in our at-
tempted locations of this boundary, we must conclude that eitli'T in many
localities the Devonian passed into the Mississippian without any con-

216 H, p. GUSHING UNCONFORMITY AT BASE OF BEREA GRIT

siderable break or else that the break is a peculiarly elusive one, hidden
in weak and poorly exposed shales in such wise that it is very difficult to
detect. If it be true that in the northern Appalachian basin the De-
vonian passed into the Mississippian without diastrophic oscillation and
sea withdrawal, then the trifling character of the break at the base of the
Berea would have no significance; but if this be not true, if diastro-
phism be periodic and is to be used as the basis of geologic classification,
it is not out of place to urge that this break is of too minor a sort to be
successfully used as an argument for drawing the line between two geo-
logic systems at its horizon. The immature stage of erosion represented
by the channels and the fact that the Berea base rests on the same thin
underlying formation all across the State seem to us cogent arguments
against the break being other than a most trifling one.

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BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Vol. 26, pp. 217-230, PL. 9 JUNE 28, 1915

OEIGIN OF THE RED BEDS OF WESTERN" WYOMING ^

BY E. B. BRANSON

(Presented before the Society December 29, 19H)

CONTENTS

Page

Introduction 217

Historical 218

Description of ttie Red Beds of western Wyoming 218

Conditions of the upper Red Bed gypsum deposits 222

Hypothesis for origin of gypsum deposits 223

Statement of the hypothesis 223

Topography of drainage area supplying water for the deposits 223

Relation of run-off to precipitation 223

Materials in solution in river waters 224

Assumptions made in working out hypothesis 225

( 'onditions not explained hy the hypothesis 22(5

What became of the calcium carbonate? 226

What became of the sodium chloride and other salts? 227

Time, erosion, and purity 228

General conclusion 228

Summary 228

Succession of events 229

Age of the Red Beds 229

TNTKOnUCTION

After woi-kiiif;- on the Red Beds (Chngwater formation) of western
Wyomin<; for four summers, the writer is convinced that some recent
investifratoi'S are assigning their origin too largely to subaerial forces.
He has found proof of such origin in one member about 60 feet in thick-
ness, evidence of scolian origin in another member of about the same
thickness, and abundant indications of subaqueous origin for all of the
rest.

The writer's investigations were made during the summers of 1904 and
1905, when he worked on the Rod Beds from about 20 miles south to

' Manuscript r«»coivpd by tho Secretary of Ihe Oeologlcal Society February 8, 1915.
XVII— Bull. Giool. Soc. Am., Vou 26, 1914 (217)

218 E. B. BRANSON ORICxIN OF RED BEDS OF WESTERN WYOMING

about 35 miles northwest of Lander and examined the exposures about
15 miles north of Rawlins, and in the summers of 1911 and 1913, when
tlie studies were continued from about '25 miles south of Lander to near
Dubois, a distance of about 100 miles; but the investigations on the Red
Beds were incidental to other work. In the main the discussion in this
paper is confined to the western outcrops.

Historical

Darton says of the Red Beds in Wyoming :

"In the latter part of tbe Carboniferous time, and probably during the Per-
mian also, there was a widespread emergence, resulting in shallow basins with
very wide mud-flats which occupied a large portion of the Rocky Mountain
province. In these regions were laid down the last deposits of the Pennsyl-
vanian division and the great mass of red clay and sands constituting the
Chugwater formation. These beds probably were deposited by saline water
under ai-id climate conditions and accumulated in a thickness of 1,000 feet or
more. The waters were shallow much of the time, and there were wide, bare,
wash-slopes and mud-flats, as is indicated by the frequent mud cracks, ripple-
marks, and impressions of various kinds on many of the layers throughout the
formation." "

With this the writer agrees, but in western Wyoming the mud-flats
appeared only two or three times.

Schuchert says:^ "The marine Triassic of California, Oregon, and
T^Tevada early in this period extended into Idaho and as continental de-
posits continued thence into eastern Wyoming." Referring to the Wy-
oming Triassic, he says: "Farther to the east all the Triassic appears to
be devoid of marine strata." Schuchert's maps in his Paleogeography
of North America show all of the Wyoming Triassic as of continental
origin, but in continuous connection with the marine formations of
Idaho, Nevada, and California.

Description of Red Beds of western Wyoming

For about 60 miles along the eastern slope of the Wind River Moun-
tains the outcrops of the Red Beds are almost continuous and the beds
reappear in a small anticline 10 to 15 miles east of the main outcrops,
though they are never exposed to the bottom in the anticline. Darton's
map* shows their distribution in a general way.

The Red Beds on the Little Popo Agie River, 15 miles south of Lander,

2 Bull. Geol. Soc. Am., vol. 19, 1008, pp. 465-466.
•^Bnll. Geol. Soc. Am., vol. 20, p. 579, pis. 86 and 87,
*Bull. Geol, Soc. Am., vol. 19, pi. 22.

DESCRIPTION OF THE BEDS 219

are 1.421 feet thick, according to Woodruff,^ and just soutli of the Big
Popo Agie Eiver stadia measurements by the writer and his party showed
1,453 feet. No complete measurements were made in other places, but
the thickness seems to run about the same in the entire region studied.

The contacl wiili i\\v ovei'lyiii.u formation, whicli in this region is the
Sundance, is usually covered; but on the west side oL' 'Table Mountain,
? miles south of Lander, tlie exposure is good in a small valley. The
contact is one of disconformity, as evidenced l)y the weathered surface of
the Red Beds on which the sandstone of the Sundance was deposited.
The same phenomenon appears in the anticline near the Dallas oil wells,
but no other evidence was found at any place.

The contact with the underlying formation is rarely seen, but on Bull
Lake Creek, 40 miles northwest of Lander, the exposure is excellent.
The beds at the bottom are of red shale, containing much pyrite; the
change to the uncJerlying Embar is merely change of color from red to
green, and sedimentation appears to have been continuous from the older
formation into the younger. ISTear Ed Young's house, on the Little Popo
Agie River, 16 miles south of Lander, a massive conglomerate up to 30
feet in thickness occurs at the contact in at least tAvo places. In neither
place was the red rock found immediately overlying the conglomerate,
but the situation was such as to leave no doubt concerning the relation-
ships of the conglomerate, and evidently a slight disconformity occurs
between the Embar and the Red Beds.

The lower 800 feet of the Red Beds in the rea^ion near Lander is
largely dark red, shaly sandstone, extensively ripple-marked and becom-
ing more and more calcareous toward the top. Some of the beds stand
out as though made of thick-bedded sandstone, uniform in iexture, color,
mill thickni'ss for long distances; but on weathering these appear shaly.
.Vt about 800 feet from the bottom the incrcasins' amount of lime in the
water terminated with a deposit of from 1 to 6 feet of limestone, which
thickens away from the mountains. The limestone was not seen in the
region north of Rawlins, though it may have been present; but in the
next outcrops, about 25 miles southeast of Lander, it apjiears and extends
northwestward for at least 50 miles. The stone is magnesian. fine
grained and compact, and is locally designated as marble. The writer
has never found a fossil in il. \A'oodiiiff says: "Locally this bed is thin-
bedded and irregular, as if deposited from hot springs." "

As it has very little pore space and is in the main non-crystalline, it
can not be secondary in origin. Tt shows no sign of being clastic. Tt is

"BiiM. 4.'>2, U. S. Oool. Siirv.. p. IK.
*]U\\\. l.M', V. S. Cool. Siirv., p. I.''..

220 E. B. BRANSON ORIGIN OF RED BEDS OF WESTERN WYOMING

not made up of shells of animals. Woodruff's theory could apply for only
very small areas, where the beds are irregular in thickness. All evidences
seem to indicate an origin from chemical precipitation, and the absence
of fossils is not peculiar with the waters so highly charged with mineral
matter.

Bed sandstone continues for 80 to 90 feet above the limestone and is
then succeeded by a heterogeneous member called by Williston^ the Popo
Agie beds. As the lower contact is always covered, the exact thickness
of these beds has not been determined, but seems to vary from less than
20 feet to more than 60 feet. For the most part the member consists of
sandy shales and mudstones. At the top a mudstone that shows no sign
of bedding ranges up to 15 feet in thickness and consists of nodules of
purplish, argillaceous sandstone. The mud seems to have been cracked
by the sun and the cracks filled in by wind-blown or flood-washed ma-
terials and the bedding destroyed, as described by Barrell.^ Much of the
formation contains rounded white spherules, usually about 0.6 millimctei-
in diameter, that appear like grains of oolite and that have concentric
structure.

In color the Popo Agie beds are usually red to yellow, but range
through various shades of green, brown, purple, and orange, with occa-
sionally white beds and uow and then carbonaceous bands. Not infre-
quently included fossil bones are black, owing to carbonization.

Here and there a conglomerate, varying in composition from pebbles
of various kinds of rocks to pieces of bone and teeth of reptiles and
amphibians, occurs among the other rocks, and this thickens and thins
remarkably in short distances. Beds of sandstone or shale 20 feet thick
may give way to something entirely different within a few feet. The
colors change abruptly and in a way that gives striking effects. The top
was eroded before the deposition of the overlying formation, giving rise to
a slight unconformity, that may be observed at most places Avhere the
contact is well exposed.

Fragments of bone and teeth are common near the upper part of the
member, but articulated bones are extremely rare. Nearly all of the
bones have been worn by being washed about, but the writer and his
party found one nearly complete crocodile skeleton and two or three
others more or less complete, and Mr. N. H. Brown collected two almost
complete amphibian skulls. These remains showed no signs of having
been transported and were probably fossilized where the animals died.

Plant remains are common and most of them consist of lanceolate

TJour. Geol., vol. 12, 1904, p. 688.

*Bull. Geol, Soc, Am., vol. 23, 1912, p. 426.

DESCRIPTION OF THE BEDS 221

leaves, though some trunks up to 4 or 5 inches in diameter occur. Fresh-
water pelecypod shells occur in a few places.

Above the Popo Agie beds there is about 20 feet of reddish, thin-bedded,
much ripple-marked sandstone that is uniform in thickness and color
over large areas. One peculiarity of this member is uniformity of joint-
ing, running almost at right angles, vertical, and usually 2 to 4 feet
apart. With the weathering away of the softer beds beneath these beds
are left standing with vertical faces, which are determined by the joint
planes. The joints are shown at the left in figure 1, where they appear
in striking contrast with the irregular jointing of the nodular beds below.

Sandstones succeed for about ISO feet, but are interrupted four or five
times by beds of chocolate-colored sandy shale, 6 inches to 4 feet in thick-
ness, that maintain the same thickness for long distances and are regular
in texture and color.

These sandstones are followed by some 50 feet of a very strikingly
cross-bedded sandstone of lighter red color than the other sandstones.
The bedding is of a type that originates from wind action,^ which the
figures of plate 9 show better than it can be described. The false beds
dip in various directions, differing from the type developed by stream
work, in which the false beds dip rather uniformly in one direction.^''
This sandstone decreases in thickness to the east and may entirely dis-
appear within a few miles, though some of it appears in the small anti-
clines some 10 miles east of the outcrops along the mountains. It was
probably subaerial in origin ; but if so, waters soon overspread the region
again and thick beds of gypsum were deposited not far above it. The
gypsum is almost pure from top to bottom, though the beds may thin
rapidly from 40 feet to 0.

If the cross-bedded sandstone is wind-blown, as according to my in-
terpretation, there is only slight change in color to separate marine from
non-marine. But great change in color is scarcely to be expected. If
tlie climate is arid, oxidation has no large effect on the wind-blown sand,
and the seas covering thin beds of such sand place them under almost
exactly the same chemical conditions as though they had been deposited
under the sea. If the coloring matter is due to some impurity deposited
with the sands, the wind-blown sand is likely to be less liighly colored,
ns it will have a smaller amount of such impurities than the subaqueous
deposits. The cross-be* I ded sandstone of the I?ed Beds is lighter colored
tlian the other sandstone.

"Bull. GpoI. Soc. .\ni., vol. 24, pp. 403 and 404.

10 J. Bancll : Criteria foi- tlic recognition of ancient delta deposits. Bull. Geol. Soc.
.\m., vol. 2n. p. 452.

222 E. B. BRANSON ORIGIN OF RED BEDS OF WESTERN WYOMINO

Almost all the Eed Bed sandstones are ripple-marked on plane surfaces
and the beds are uniform in thickness and texture for long distances.
Beds that occur 15 miles south of Lander may be traced along the out-
crops almost continuously to Bull Lake Creek, a distance of some 60
miles, with slight variations in thickness and texture — variations so small
that only detailed measurements could detect them if they are present.
This is true for all the beds noted by the writer excepting the gypsum,
Popo Agie beds, cross-bedded sandstone, and the limestone. Such regu-
larity is found only in deposits made in bodies of standing water. Bar-
rell says: "It appears, therefore, that typical water-made ripple-marks
associated with regularity of bedding in sandstones is especially associated
with the subaqueous plain of deltas and the bottoms of shallow seas." ^^

The cross-bedded sandstone is succeeded by red sandstone, and gypsum
beds occur only a few feet above it. In the Lander region the gypsum
rano-es from a few inches to 40 feet, but maintains a thickness of a few
feet for long distances along the outcrop. The thick deposits are limited
in extent, rarely running for more than a mile, and seem to be fillings
of depressions in the main basin floor when the deposition took place.
The g}'psum is remarkably pure and deposits 40 feet in thickness contain
only a few thin partings.

It is the writer's opinion that the gypsum beds are strong evidence of
the subaqueous origin of the Eed Beds, but Mr. Scliuclieit nia])S the IJecl
Beds as subaerial in his paleogeographic maps, and an eminent stratigra-
pher wrote me, after reading the first draught of this paper: "Xote the
extreme vai-iiil)ility of your gypsum deposits. Translate this into topog-
raphy and you get a series of pools. . . . T would rather you test out
the idea that these are fresh-water deposits under an arid climaTe such
as the Triassic was in this region."

It seemed worth while to give this liyjiothesis n quantitative test and
the results are outlined below.

CoxDrriONs of the uppki; 1\i:i) I>ki) (ivi'sr:\[ Drposits

L The gyi'suni outcrops in ])laces oxci- an area of at least "iO,!)!)!!
square miles.

2. Probably half of the 20,000 square miles is underlain by gypsum
averaging 1 foot thick and one-tenth oL' ihe ai'ea by beds 10 feet thick
or more.

3. It thickens and thins reinarkal)ly in <lioii dis(;in(a'<. i^angini; fi-oni
a few inches to 40 feet.

liBull. Geol. Soc. Am., vol. 23, p. 420.

CONDITIONS OK THE (iVPS^'^[ DEPOSITS . 223

4. The beds are often discontinuous.

5. The beds occur at many horizons, but in western Wyoming ;iiv
mainly near the top, and some are near the top in must ot the nivas ot
outcrop.

6. The gypsum is remarkably pure and salt has nevei' been reported

in association with it.

Hypothesis por Origin op Gypsum Deposits
statement of the hypothesis

The gypsum deposits of the upper Eed Beds originated Itohi concen-
tration of fresh water under arid climatic conditions.

In order to test this, tlie topography of the area, drainage conditions,
content of stream waters, and rate of evaporation were studied.

TOPOGRAPHY OF DRAINAGE AREA SUPPLYING WATER FOR THE DEPOSITS

The topography of the region surrounding the Eed Beds basin in
which the gypsum was deposited is conjectural, but the topography of
the area of the basin itself may be postulated with tolerable certainty.
No unconformity that is detectable has been seen in the upper beds, and
if the red sandstone was exposed for many thousands of years, it must
have been very low and flat to avoid leaving traces of erosion. The Red
Beds occur over most of eastern Wyoming, with an area of some 40,000
square miles, and the sand-covered plain must have been of about that
extent. The source of the red sands is uncertain, but the uniformity in
thickness and continuity of the Eed Beds indicates that the places in-
vestigated are not near the margin of the area of sedimentation, and
thinning to. the eastward indicates that the highlands were to the west.

RELATION OF RUN-OFF TO PRECIPITATION

Streams with low gradients flowing through arid regions are likely to
carry only a small amount of the rainfall of their drainage basins. At
Uva, Wyoming, the run-off carried by the Laramie Eiver is usually les-^
than 10 per cent of the rainfall of its basin, with an area of 3,1?9 square
miles.^- In 3896, 1897, and 1898 Ihe run-off of the Arkansas Eiver at
Hutchinson, Kansas, with a fall of 5.G feet per mile, was less than .3
of 1 per cent of the rainfall of its basin; at Canon City, Colorado, I'M
miles from the head of the Arkansas, and above which the fMll langes
from 30 to 63 feet per mile, the run-off is 20 to 30 per cent of llic rnin-
iidl ; at Oranite, Colorado, 2 I miles from the head of the Arkaii<,is. ,ind

'* Twentieth Annual Report of U. S. Geological Survey, vol. Iv. p rA.

224 E.. B. BRANSON ORIGIN OF RED BEDS OF WESTERN WYOMING

above which the fall is 55 to 63 feet per mile, the run-off measured in
1897 was 70 per cent of the rainfall.^"' llelatioiis of like character hold
for nearly every river that leaves the mountains and flows across the
more arid plains. A run-off of 30 to 70 per cent is to be expected of
streams emerging from mountain regions and of 1 to 20 per cent for
streams that have run for some distance through arid plains.^*

MATERIALS IN SOLUTION IN RIVER WATERS

When waters from the upper reaches of rivers are analyzed they gen-
erally have only a small amount of mineral matter in solution and show
iriore and more concentration as arid plains are crossed and the water
taken by evaporation is replaced from underground sources, but salinity
may decrease or increase if the stream continues to flow through arid
plains.

The Arkansas Eiver has a salinity of 148 parts per million at Caiion
City, Colorado, where the run-off is 20 to 30 per cent; 2,134 parts per
million at Eoeky Ford, Colorado, and an average of 630 parts per million
at Little Eock, Arkansas. ^^

In streams flowing over sedimentary rocks in arid regions the sulphates
frequently become more abundant than the carbonates. Clarke says:'"
''In arid regions sulphates and chlorides prevail." But on an average
the sulphates are only slightly in excess of the carbonates.

The region postulated consisted of horizontal sandstone, probably
poorly consolidated, with an area of some 40,000 square miles and with
slight relief. No stream analyses from such a region are available, but
it is probable that stream data from the loveler parts of Wyoming, where
the rocks are sedimentary, will answer as well as any to be found.

Slosson^^ g'wes six analyses of waters from the Popo Agie Eiver,
Laramie Eiver, and Little Goose Creek, streams that occur in the region
under discussion and are typical of it. The Popo Agie analysis is of
waters emerging from the mountains into the plains niid the Laramie
and Goose Creek analyses are of waters that have run for some distance
through arid plains.

In stating the analyses in hypothetical combinations, Slosson gives
calcium sulphate in the Laramie Eiver only, and three out of five analyses
f]-om it show none. Eecalculation of tliree of Sk)sson's analvses of waters

" Ibid., pp. 56-57.

"Water Supply Paper 306 of the U. S. Geological Survey contains maps, plates 1 and
2, showing relationship of run-off to precipitation.
i» Clarke: Bull. 11. S. Geol. Surv., 491. p. 70.
" Ibid., p. 81.
1" Wyoming Experiment Station, Bull. 24.

HYPOTHESIS FOR ORIGIN OF GYPSUM DEPOSITS 225

of the Laramie, using all of the SO4 in CaSO^, gives oo.S parts CaSO^
per million. Eecalculation of an analysis of water taken TO miles below
that given above and "more or less contaminated by seepage from the
canals/' using all of the Ca and 36/37 of the SO^, gives CaSO^ about
220 parts per million. ^^ Eecalculation of the Popo Agie analyses, using
all of the SO4 in CaSO^, gives 8.67 parts per million.^® Recalculation
of the mean of 29 composites of the North Platte, at North Platte,-''
Nebraska, using all of the SO^ in CaSO^, gives a calcium sulphate con-
tent of about 198 per million.-^ (The North Platte analyses are used
because the river flows almost entirely on sedimentary beds across Wy-
oming and Nebraska.)

All of these waters are high in calcium carbonate, and in only one
analysis is there more than enough calcium to unite with the CO3, but in
most cases this union takes place early in the process of concentration
and limestone is precipitated. Most of the sulphuric ions would prob-
ably unite with sodium and magnesium, as they have done in the pre-
cipitates formed in the alkaline lakes of Wyoming, where sodium sulphate
and magnesium sulphate make up most of the deposits and calcium sul-
phate is present in small amounts.^- The calculated amount of CaSo^ is
then much too high, as all of the sulphuric ions should not be used with
calcium. From the data available it seems that 50 parts of calcium
sulphate per million is more than would precipitate from waters that
have run some distance, at low grade, through arid regions, and that the
amount furnished by streams as they emerge from regions of high relief
would be less than 10 parts per million.

Analyses of six streams tributary to Great Salt Lake show an average
calcium siilpliate content of 120 parts per million, if all of tlio sulphuric
ions are used with calcium; but in all but one of these analyses there is
not enough calcium to combine with all of the CO3 ions. All of the
calcium luis been precipitated fi-oni the lake, much of it as calcium cai'-
bonalc. As with the W'vorninu- ri\crs. it seems ])i'()l)al)le that .")0 parts
per million calcium sulphate in the water is more than would he pre-
cipitatiMl on e\aporation.

ASSUMPTIONS MADE IN ^VORKINO OUT HYPOTHESIS

Assumptions foi- origin of 1-foot bed of gypsum over 1(1.00(1 square
miles, but with the deposit ion in nianv. nioi'c or less isolated, lakes:

'* Runoff al)Out 10 i)er cent.

'" 'riie run-off probably 50 to 70 per cent, but rolialjle data is n(jt availulile.

-" Kun-offi less than 10 per cent. Data not satisfactory.

■-■'Clarke: TT. S. Geological Survey, Bull. 4f)l, p. 74.

•^Wyoming E.xix^rluieut Station, Bull. 40, pp. 110-121.

226 E. B. 15KANS0N ORIGIN OF RED REDS OF WESTERN WYOMING

1. Lakes must have depths of hundreds of feet to prevent concentra-
tion to point of precipitation for salt.

2. Conditions of drainage basin, part 1 : (a) Eelatively flat sandstone
area 30,000 square miles in extent; (h) rainfall, 10 inches; (c) nin-
off, 10 per cent; (d) 50 parts per million calcium sulphate in the run-off
waters. Enough calcium sulphate brought in each year to make a layer
.000075 inch thick.

3. Conditions of drainage basin, part 2: (a) Highlands area of -13,000
square miles; (h) rainfall, 15 inches per year; (c) run-off, 10 inches
per year; (d) 10 parts calcium sulphate per million in inflowing waters.
Enough calcium sulphate brought in each year to make a layer .000221:
of an inch thick over the receiving basin.

Total calcium sulphate brought in each year about .0003 of an iucli,
and about 40,000 years required to bring in 1 foot. Evaporation required
over the receiving basin, 58 inches per year.

Assumptions for 10-foot gypsum deposits over 2,000 square miles:

1. Basins must have a depth of hundreds of feet to prevent dry
seasons from bringing water to point of saturation for salt.

2. Conditions for drainage basin, part 1 : (a) Relatively flat sandstone
area 38,000 square miles in extent; (h) i-ainfall. 10 inches per year;
{<■) run-off, 10 per cent; (d) 50 parts calcium sulphate brought in each
year to make a deposit .000475 iuoli thick ovei- the 2.000 square mile
basin.

3. Conditions for drainage basin, part 2 : (a) Highlands of 43,000
square miles: (/)) rainfall, 15 inches; (r) run-off', 10 per cent; (//) 50
parts per million calcium sulphate. ( A lower run-off and higher calcium
sulphate content assumed because the mountain streams now flow for
some distance over the arid plains.)

Enough calcium sulphate brought in each year to make a deposit
.0008 inch thick over the 2,000 square mile basin.

Total of .001275 iuc-li of gypsum per year, x^bout 85,000 3'ears re-
quired to get 9 feet of gypsum.

Sixty-one inclies of water per year over the entire surface of tlie basins
must be evaporat<'(l on the above assumptions.

("OVDITIOXS XOT EXPLAIXEI) HY TIIR HYPOTHESIS '
WHAT BECAME OF THE CALCIUM CARBONATE*

As previously stated, the carbonates are nearly as abundant in the
sTreani waters as the sulphates. Calcium carbonate would be in practi-

CONDITIONS NOT EXPLAINED BY HYPOTHESIS 227

cally the same amount as oalcinm sulphate, and if the concentration took
])lace from fresh water in inclosed basins, limestone of practically the
same thickness as the g}'psum should be present with the gypsum. But
limestone is rarely associated with the gypsum and is never interbedded
with it, as would necessarily be the case unless the gypsum and lime
were deposited together and the resulting rock were a mixture.

In the waters of Great Salt Lake, Sevier Lake, and other lakes of high
concentration little or no calcium and CO3 are present. Clarke says that
"all of the waters tributary to Great Salt Lake, so far as they have been
examined, contain notable quantities of carbonates, which are absent
from the lake itself. These salts have evidently been precipitated from
solution, and evidence of this process is found in ])eds of oolitic sand,
composed mainly of calcium carbonate, which exist at various points along
the lake shore." ^^

Lake Lahontan, with watci-s of a siliiiity one-fifth to one-tenth as high
as the Great Salt Lake, has already had most of the lime salt thrown
down as tufa, while the SO^ content remaiiis liigh. Lake Lahontan
represents concentration of fresh waters, but as its ili-ainage basin is
largely composed of igneous rocks, the sulphates would probably be lower
Ihan in the fresh -water pools postulated.

WHAT BECAME OF THE SODIUM CHLORIDE AND OTHER SALTS?

Deposits of salt are not mentioned in connection uiili tlu' upper llr^l
Beds, but it is frequently equal in amount to gypsmn in streams in arid
regions and probably averages one-half to one-fourth as al)undant. As
no salt beds occur, the solutions must have remained considerahly above
saturation, ami ')i> to 100 feet of water must have been left in eaeli pool
to contain the salt ; but it seems almost certain that some ]Wols woulil
have dried up and the more soluble salts have been precipitated. Some
salt may have been deposited and redissolved, !)ut there are no t'\ idences
of this in the rocks, and waters from wells ]»enetrating tlie l)eds do not
carry unusual quantities of salt. If some of the pools had dried up, a
series of alternating \H'i\<- of \ai'ious salts wouM lia\'e been foi-nuMl : but
such deposits ai'e ne\cr found in the T»cd Ileds. 'I'lie waters e()uld not
escape fi'oni the region without reuniting, and if they reunited and
were di-ainc(| hy land \\;ir|)ing. a large pari of the region must have been
submergeil and suha(pieous deposits must have heen loi'me(| over the
gypsum.

=»U. S. Geol. Siiiv. IJiill. i<M, p. ]4<i

228 E. B. BRANSON ORIGIN OF RED BEDS OP WESTERN WYOMING

Sodium sulphate and magnesium are not associated with the gypsum,
but are very abundant in most waters of arid regions, and the concentiu-
tion could not have reached the place where they would be deposited.

TIME, EROSION, AND PURITY

The time necessary for the deposits from fresh water seems prohibitive
when it is considered that there is no sign of erosion laterally from the
gypsum beds before the next beds were laid down. More or less uncon-
solidated sand would erode rapidly and it seems necessary that the
erosion time be short. The purity of the beds seems to preclude great
length of time. Some sediments must have been brought in by streams,
and the winds would have brought in large amounts, but these thick
beds of gypsum are in most cases relatively pure from bottom to top.

General Conclusion

It is practically impossible for thick beds of pure gypsum to form from
fresh water under arid climate conditions.

Summary

The following evidences are presented as indicating marine origin for
most of the Eed Beds of western Wyoming and the presence of the
gypsum as pointing to marine origin for the upper Eed Beds of most of
W'^yoming :

1. Uniformity in thickness of beds over wide areas.

2. Uniformity in texture of rocks over wide areas.

3. Eipple-raarking on horizontal beds through most of the formation.

4. Chemical precipitate of limestone at the 800-foot level.

5. Chemical precipitate of gypsum near the top over wide areas and
at various levels in many places.

6. Absence of sun ci'acks and fossils of land animals excepting in the
Popo Agie beds.

7. Presence of undoubted subaerial evidences in the Popo Agie beds,
with textures and materials like much of the rest of the Eed Beds.

succession of events 229

Succession of Events

1. The Eed Beds began nnfler marine conditions and the sea gradually
became more and more charged with calcium carbonate and magnesium
carbonate until a dolomitic limestone was precipitated.

2. Above the limestone the sea gradually filled with sand until the
sediments were exposed and the Popo Agie beds were formed under sub-
aerial conditions.

3. The sea in Upper Triassic time readvanced and some 200 feet of
sandstone and shales filled the western margin.

4. Subaerial deposition, mainly of wind-blown sand, succeeded and
lasted while beds varying from a few feet to 60 feet in thickness were
deposited,

5. The sea readvanced, but concentration of calcium sulphate had been
in progress for a long time and soon resulted in wide-spread deposits of
gypsum.

6. Usually some sandstone and some thin layers of limestone were
deposited above the gypsum before the withdrawal of the sea at the close
of the period.

Age of the Eed Beds

The age of the upper Red Beds in western Wyoming deserves passing
notice, though Williston^* has recently stated the evidence. The writer
and his parties have never found a fossil in the formation outside of the
Popo Agie beds. From these beds Williston^^ has described four genera
of reptiles, one closely related to Keuper forms of Europe and the others
to South African forms. Tlic writer has described^" two species of
amphibians similar io Kciijicr foi'ms of Europe, and Mehl has described^^
a phytosaur similar to those of tlio Keuper of Europe and Newark of
North America. To any one fa mil in i' with Triassic reptiles and am-
phibians the evidence of tlio Upper 'I'riassic age of the Popo Agie beds
is conclusive.

Below the Popo Agie beds no evidence of a break in the continuity
has been seen by the writer a.nd it is possible that the sedimentation was
continuous through Upper Permian and Lower Triassic. As mentioned

« Jour. Geol., vol. 17, p. 396.

= .Tour. Geol., vol. 12, pp. 688-«r»6.

'^ .Tour. GpoI., vol. l."'.. pp. .''.60-.'')S0.

=^Jour. Geol., vol. 21, pp. 186-101,

230 E. B. BRANSON ORIGIN OF RED BIRDS OF AVESTERN WYOMING

before, the contact of the Popo Agie beds with the under] vino- sandstones
is always covered and a disconformity may exist at that place. It is
possible that the Eed Beds below are Permian, and that the Upper
Triassic rests disconformably npon them. The Red Beds above tlie Popo
Agie beds arc surely Triassic in age for some tliickness, and probably to
the top, though there is no positive evidence tliat the upper ipari is not
Jurassic. The marine Upper Jurassic lies unconformably on the Red
Beds.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA
Vol. 26, PP 231-242 JUNE 28, 1915

OKIGIN OF THTC'K GYPSUM AND SALT DEPOSITS^

BV E. B. BRANSON

(Read before flie Society Becemher 30, U'l.'^)

CONTENTS

Page

Introduction 231

Phenomena not explained by published hypotheses 231

Some conditions for salt and gypsum deposits 232

Modified bar hypothesis 235

Origin of thick salt deposits 237

Tlie example of the Caspian Sea 238

The Salina salt 238

The gypsum deposits of the upper Red Beds of Wyoming 240

Summary 241

Introduction

The origin of thick deposits of gypsum without associated deposits of
salt and of deposits of salt of great thickness are still open questions and
no published hypothesis seems adequate to explain them. This was
brought forcibly to the writer's attention by a study of the gypsum
deposits of the Red Beds of Wyoming, some of which are more than 40
feet thick, and the modified bar hypothesis outlined below was gradually
evolved. As the various theories have Ijeen fully explained in many
pUices,^ it is not necessary to restate them; but a consideration of the
more important phenomena that thoy do not explain seems worth while.

Phenomena not exi'i.aim;i) i'.v itiblished Hypotheses

The main diflRculties in explaining the origin of thick gypsum deposits
are: 1. In accounting for the volume of water required to contain the
calcium sulphate in solution, necessitating a depth of basin in excess of
any kno^vn continental depression; 2. In explaining the rarity of other

> Manuscript rpcelvrrl hy ihc Socrptary of the Society February 8, Ifllo.
= See particularly A. W. Oraban : rrinclples of stratlprnphy. pp. 347:180.

(231)

232 E. P>. BRANSON THICK GYPSUM AND SALT DEPOSITS

salts in the deposits; 3. In accounting for the absence of salt deposits
above the gypsum; 4. In explaining the absence of sedimentary impuri-
ties; and 5. In accounting for the absence of fossils. The diflBculties in
explaining thick deposits of almost pure salt are : 1. Prohibitive depth of
water required to contain the salt in solution; 2. Lack of alternation of
salt and gypsum in many thick deposits ; 3. Thick salt deposits without
gypsum below ; 4. Absence of fossils in the deposits.

Some Conditions for Salt and Gypsum Deposition

Sea-water contains 1.7488 parts per thousand calcium sulphate in
solution, but as salt begins to precipitate rapidly soon after 1.4 parts of
gypsum have been deposited, only about 1.4 parts per thousand is avail-
able for deposition in pure gypsum beds. Usiglios' experiments^ show
gypsum beginning to deposit from sea-water after .81 of the volume has
been removed by evaporation and sodium chloride beginning to precipitate
after .905 has been removed in that way. The total amount of gypsum
precipitated in the evaporation from .19 original volume to .095 original
volume is 1.466 parts per thousand. As gypsum contains 18 parts water
for every 127 parts calcium sulphate and its specific gravity is slightly
above 2.3, the volume of gypsum pi'ecipitated would be about as 1 to 2
compared to the weight of calcium sulphate in solution. From 1,000
feet of normal sea-Avater about .7 feet of gypsum would be precipitated
before the point of saturation for sodium chloride would be reached, and
it would require a depth of 57,000 feet of water for 40 feet of gypsum.
Thick deposits would probably result from the drying up of extensive
interior seas, and M'ith the drying up the waters would occupy smaller
and smaller areas and become more and more concentrated. Gypsum
would not begin to precipitate until four-fifths of the water had been
evaporated, and the depth of -water to contain 40 feet would need to be
only about 11,500 feet; but this is still much greater than the depth of
any continental depressions.

The bar theory of Ochsenius helps this out to some extent, for if a
new supply of sea-water were brought in over a bar as fast as evaporation
took place, not all of the water would need to be in the basin at the same
time, and the minimum depth of the basin would be regulated finally
by the water required to keep the sodium chloride in solution. As sodium
chloride begins to deposit when sea-water has been reduced by evapora-
tion to .095 its original volume, the evaporation of the 57,000 feet must

» stated In several recent English works. See U. S. Geol. Surv. Bull. 491. Clarke :
The data of geochemistry, p. 208, and Grabau : Principles of stratigraphy, p. 349.

CONDITIONS OF DEPOSITION 233

not reach that stage, or there will Ije salt deposits above the gypsum.
'I'herefore the water will have to have a depth of more than 5,400 feet
when the last gypsum is deposited.

Beds of gypsum 40 to 50 feet thick occur in many places, but seem to
be veiT limited in extent, and tliey often grade laterally into deposits of
wide extent, 10 feet or less in thickness. 'i4ie literature on gypsum
places little emphasis on the small extent of the thick deposits, but a
careful study of the sections given in various publications indicates the
patchiness. The thick Eed Bed gypsum deposits of Wyoming are rarely
more than 1 square mile in extent and occupy a small area compared to
the total. A rough estimate would be 100 square miles of 40 to 50 foot
gypsum and about 2,000 square miles of 10 -foot. If 11% feet were de-
])osited over the entire area, the thicker beds could originate by currents
shifting gypsnm along the bottom and filling up the deeper depressions.
All of the thick deposits noted by the Avriter in the Red Beds were related
to the thinner deposits, as indicated in figures 1 and 2, and this is con-
clusive proof that the waters were not much deeper above the thick
deposits than above the thin. The extra depth of water required for 40-
foot l)eds over that for 10-foot beds is about 9,000 feet, if the precipita-
tion is from water five times as concentrated as normal sea-water, and it
follows that if the extra thickness was from direct precipitation the beds
should be depressed some 9,000 feet below the 10-foot beds. Deposits
10 feet thicker than the surrounding beds would require an extra depth
of water of about 3,000 feet. These relations are shown to scale in fig-
ures 1 to 4.

If tlic 10-foot beds were deposited and the waters then gathered in
smaller pools, ihc gypsum might be redissolved and carried in by stvoaius.
Sli-('iiiiis llowiiiL:' over gypsniu bods c;irrv more calcium sulphate in soln-
lion than oi'dinary streams, Init do not carry enough to add rapidly to
the in(lose(l waters. Tn Clarke's "Data of Geochemistry" the highest
lalcinin snlpiiate content given for any stream water is about ! part to
1.000 by weight (using all of the Ca in the water in forming CaSO^)
for the Santa Maria River, 25 miles above Santa Maria, California.* If
such water came in fast enough to balance 5 feet of evaporation per year,
1 foot of gypsum would be supplied every 400 years; but calcium sulphate
makes up only about .4 of the material in solution in this water, and a
larger volume of other salts would probably be deposited than of gypsum.
The sediments carried in by the streams would probably amount to sev-
eral times as much as the materials carried in solution and the gypsum
would make up only a small part of the total deposit. In this connection

" Data of peochomisti-v. Hull. 4;il. I'. S. CJpoI. Siirv.. p. 70.
Win -Bull. Okoi,. Soc. Am.. Vol. :^6, 1014

284 E. a. BKANs'iso^ — THICK avrtsL M a:sd salt j)eposits

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FiGURic 1. — Idealized Section of (lyiisinii lu-dx
To show relation of 20-foot: beds of gypsum to 10-foot beds jis they ncciir near Lander.
Wyoming. Scale, 1 inch to 1.200 feet. Gypsum bed between (he black lines bounding
the stippled ai'eas.

FiGUHE 2. — Idealised Section of Gi/pfudii lieds
To show relation of 40-foot beds of gypsum to 1.5-foot beds as they occur near I,anrtcr,
Wyoming. Scale, 1 inch to 1,200 feet. Gypsum bed' between the blaciv lines bounding
I he stippled areas.

Figure 3. — Idealized Section of Gypsum Beds drawn to Scale
To show relation of 20-foot beds of gypsum to 10-foot beds if the deposits originate
from direct precipitation from waters five times as concentrated as normal sea-water.
Scale, 1 inch to 1.200 feet. The receiving basin would have slopes of 50° or greater.
Gypsum bed between the lower lines. The 20-foot bed is at .3, about 3,000 feet below
the 10-foot bed, into which it grades at the upper corners of the diagram.

Figure 4. — Idealized Section of Gypsum Beds drawn to Scale
To show relation of 40-foot beds of gypsum to 10-foot beds if the deposits originate

from direct precipitation from waters five times as concentrated as normal sea-water.

Scale, 1 inch to 5,000 feet. Gypsum represented by the heavy black line.

The diagrams illustrate the impossibility of thick deposits, in continuous beds with

thin deposits, originating from direct precipitation without lateral shifting of the gj-psum

along the bottom. In diagrams 3 and 4 the space between the stippled, horizontal bed

and the gypsum bed represents sandstone.

('()M)jTi()i\s ()i<^ DErobiTioN; 235

it should 1)0 horuv in mind that tlie tliick deposits arc only a few square
miles in extent in any basin, and that the waters would necessarily remain
deep enough to keep all sodiuju chloride and more soluble salts of the
original ocean water in solution.

With a number ol' deeper pools m which the thick gy[)siim deposits
are made it seems highly improbable that none of them would evaporate
lo the stage where sodium chloride and the more soluble salts would be
deposited. Perfect Ijalance between inflow and evaporation would be
ha 1(1 to maintain in a considerable number of unconnected pools, and
l)robably some of them would have no inflowing streams and would dry
u|) very r-apidly. But the ^Vyoming deposits seem never to be associated
with salt beds.

A 40-foot bed of gypsum, resulting from the evaporation of 57,000
feet of normal sea-water, should have nearly •'! feet of limestone below it
if the evaporation all took jdace in a I'estricted basin; but if the waters
were wide-spread in the beginning, al)Out half of the limestone might be
deposited over the widei' area, as more than half of the CaCO,, precipi-
tates when the Noluine of sea-water is reduced about 50 per cent, and the
limestone below the gypsmn might be less than 2 feet in thickness. The
writer has not seen limestone immediately below the gypsum at any place
in the Eed Beds.

Grabau discusses^ the abundance of animals that are brought into in-
closed basins that ha\o partial connection with bodies of Avater that supply
as fast as eva]ioratioii depletes their waters, and concludes that gypsum
and salt deposits, formeil where normal sea-waters supplv, across a bar.
the watei's taken liy e\aporation, should be highly fossiliferous. 'I'hiek
gypsum and salt de|)osits are usually non-l'ossiliferous.

drahau" emphasizes the agency (d' streams and winds in cari'ving
enioi'esccnf gypsum lo inlei'ior basins, hut it is e\'ident that such deposits,
ir they are e.xtensixc. can not be pure, as the sti'eams and winds would
cari'y silt, sand, and otluu' minerals with the gy])sum. The gypsum of
ihe Wyoming i?ed Beds is remarkably free from sediments and other
minerals, and I hough the entire r(\a'ion surrounding must have been of
led sands and cdays. the gypsum beds are white and pui'o.

Modi m i:n \\\u Ih I'OTFiKsrs

.\ modified bar theory seems to explain the phenomena of thick gypsum
and salt deposits, and the niodifleation consists of supplying the receiving

^ I'rinclples of stnitiprii-ih.v. p. :^66.
» I'liiKiplcs of Klriillgraidi.v. p. :!f!7.

236 E. B. BKAKSON THICK GYPSUM AND SALT DEPOSITS

basins with liighly concentrated waters instead of normal sea-water. In
the drying up of a large interior sea the waters might come to lie in
separate basins if the bottom were uneven. Evaporation over the full
expanse of the interior sea might be rapid enough to decrease the depth
and area in spite of the inflow of some stream, but when considerable
areas of bottom had become exposed the total evaporatiou would have
become less and the inflow nearer to the amount of evaporation. As-
suming that isolated basins would be formed, separated by low barriers,
and that the main streams would empty into the marginal basins, the
inflow might be sufiicient to cause these basins to overflow and supply
the inner basins, that had no direct stream connections, with highly
charged Avaters as fast as their own waters evaporated. As licds of gyp-
sum 10 feet in thickness are wide-spread, a depth of water great enough
In contain the salt of sea-water evaporated to deposit them must be as-
sumed, and the evaporation must not be carried beyond nine-tenths of
the original amount if the salt is to remain in solution. The depth of a
basin for 10 feet of gypsum would have to be at least 1,400 feet and
])0ssibly 1,500.

The concentration might have reached one-fifth the original mjIuuk'
of sea-water when the isolated seas were formed, and the waters contain-
ing .3 per cent of calcium sulphate would bring 1 foot of gypsum for
every 333 feet of water. If the excess evaporation from the inner pools
were 5 feet per year, a foot of gypsum would be brought in every 67
years. With the overflow of the outer basins the salinity would decrease
and the amount of gypsum brought in would become progressively
smaller; but, correcting for this, 5 feet of calcium sulphate Avould be
brought in in less than 400 years. The waters of the basin 1,500 feet
(h^ep wduhl contain al)0ut 5 feet of gypsum before the other waters came
ill, and 10 feet in thickness is thus accounted for. With this raj^id
deposition and freedom from stream inflow the deposits would l)e less
likely to contain impurities of a sedimentary nature than witli slower
deposition and inflow from streams.

In the waters of the Caspian Sea calcium sulphate is as about 1 to 8
compared to salt, while in ocean water it is about as 1 to 1 7. The
evaporation of water of this salinity would give gypsum deposits twice
as thick as postulated.

The writer has not been able to find data on the rate and completeness
of mixing of inflowing fresh waters with the saline waters already in the
basins. The surface waters of the Caspian are relatively fresh near the
mouths of the large inflowing rivers, but the salinity seems to be almost
imiform from top to bottom at no great distance from the rivers. The

MODIFIED BAR HYPOTHESIS 237

fresh waters would probably flow over the top of the highly charged
waters if the receiving basins were very small, but they would probably
mix thoroughly Avith the saliue waters in large basins, and the waters
furuislied to the secondary basins would be of the nature postulated.

in discussions of the bar theory of Ochsenius the backflow from the
isolated basin has often been emphasized, but the backflow would be im-
portant only where evaporation did not keep pace with inflow. Accord-
ing to the postulates of this paper, evaporation kept pace with inflow and
the depth of water on the bar was too shallow to allow backflow.

Jf connected with the open sea, across a bar, animals would come in
with the inflowing water, and, perishing on account of the salinity of tlie
waters in the. basin of deposition, would make the deposits abundantly
fossiliferous; but with the. high concentration postulated under the liy-
pothesis outlined above life would have ceased to exist in the supplying
basins before the gypsum deposits began and no fossils would he present.

With the conditions postulated, gypsum deposition might automatically
stop. The filling up of the outer basin with sediments would cause more
water to flow over to the inner basin, and this fresher water might en-
tii'cly stop the gypsum deposition by causing the inner basin to overflow
and would prevent any salt being deposited.

Origin of thick Salt Deposits

The conditions outlined above are much more favoj-able for thiclv salt
deposits than for gypsum. Suppose a sea with a doptli of 1.500 feet
were ten times as concentrated as sea-water and had losi most of its
gypsum as explained above.

The water left above the g}'psum wouUl contain about l-") IVet of salt
per 100 feet, and if this were evaporated to alxmt oiic-roiii-ili its vtduiiu".
or .023 the original volume of normal sea-water, alioiit ! '?'•_. Icot ol' salt
wiMild be deposited for every 100 feet of water. (»r n totnl of 1 1.") feet for
l..")(Mi foot. A\'ith tliis would be associale(l alioiil •.'!._, per cent of iiii-
purities, roiisisting ol CaSO.,, MgSo.,, MgCl.., and Nalir. With A iVcl
excess evaporation per year, tlio deposit of 175 feet of salt would be
foi-iiitMl in 75 years.

But many times there are no thick deposits of gypsum below the salt
and this is easily accounted for. Suppose that the basin is caused to
overllow l)y iiifiow of fresh water and its waters flow into another depres-
sion of oni'-ti'Mlh its area, in which no deposits bad prcviouslv been
formed. If r\ apoiat mn here keeps pace with inflow after tiie basin is
pai'tially filltMl, and if excess eva])oration is 5 feet per year, 820 foet of

238 E. B. BRANSOK THICK GYPSfM AND SALT DEPOSITS

salt, with about 2^ per cent impurities, as listed above, will be deposited
in 1,500 3^eaTS, if the basin is deep enough to receive so miic]i.

The loss from the larger basin would be 6 inches per year and, replac-
ing this with fresh water at the rate of 6 inches per year, its concentra-
tion would be only three-fourths as great at the end of 1,500 years, and
the total amount of salt carried in by the waters would be seven-eighths
as much as though the same concentration had been maintained. This
correction has been applied to the computation in the preceding para-
graph.

The Example of the Caspian Sea

The Caspian Sea and its Gulf of Karaboghaz furnish conditions analo-
gous to those postulated save in the solutions. The area of the Caspian
is about 169,000 square miles and of tbe Gulf of Karal)oghaz 7,100 sqTuire
miles. The gulf is separated from the main sea by a narrow sand-bar
pierced by a strait, 1^ miles long and 115 to 170 yards wide, through
which a current flows continuously into the gulf at the rate of 11/^ to 5
miles per lionr. and there is no cojiipensating outflow. The evaporation
from the gulf is 3.2 feet per year.'''

If the gulf were deep enough to accommodate large amounts of water
and the incoming waters from the Caspian had already deposited most
of their gypsum, great deposits of salt would be formed.

The Salina Salt

Schuchert's map of the Salina Sea shows it covering an area of a little
mure than 220,000 square miles and the salt and gypsum deposits extend-
ing over about 12,000 square miles. If this sea were 900 feet deep and
evaporated to one-third the area and ono-tliird the depth, it would leave
about 73,000 square miles of inland lakes witli a depth of 300 feet and a
concentration nine times as great as in the original sea. ■ Fov convenience
in computation, it is assumed that the concentration was ten times tliat
of the original sea-water. Assume that the drainage from the surround-
ing region practically all came into 60,000 square miles of the lakes and
these overflowed to supply the loss from evaporation of the other 13,000
square miles of lakes. If the rate of evaporation was 5 feet per year, the
rainfall over the inland seas 1 foot, the overflow foirr-fifths of 1 foot, and
the run-off over the drainage basin 8 inelies, tlie area of tbe drainage
basin must have ])een al)out 360.000 s(|u;ii'(' miles, in .-idditiii;! td tbe area
of the lakes, to supply the necessarv water. 'I'his is ;i little less tlinii oiie-

Bncyclopedia Britauuica, 19\'2.

TIIK 8ALINA 8AT-T

239

third the area of the Mississippi basin — a little less than the area of
Ontario, Michigan, Ohio, Pennsylvania, and New York. The 100 feet
of salt mig-ht be brought to the settling basins in about 166 years, as ex-
plained in an earlier paragraph.

FlGUUE 5. — Mai' sJioiriinj Ii miothetivul merftuir Bdniiis (i)i(l Ihisinn of Salt unii Uihikuiii

Deposition duriny tiaiina Time

The outline and salt and gypsum areas are copied from Schiichert's map of the Saiina
Sea as jiiven in Bulli'tin of the Geological Society of America, vohime '20. plate 69. The
map is presented to illustrate an liyi)«)thesis and uo claim is made that it shows actual
conditions.

(Jrabau says'* thai a salt hi'd 100 iVct iliick and covering :^'').()0(J square
iiiilcs is proliaWh in i-xcrss of llic area con ci'i'tl Ky tliick salt IxmIs. If tlif

■< MIchiuaii Cci.liiKic'iil niul r.ii.I,.i:iciil Survey. I'ulill.'adon •_', p. 'j:^!!.

240 E. B. BRANSON THICK GYPSUM AND SALT DEPOSITS

salt beds had this extent the basins may have been on a larger scale, but
as the beds are not all contemporaneous the l)asins postulated are prob-
ably larger than are required.

The same author states "that for every great salt deposit formed in
the neighborhood of the sea by concentration of sea-water, there should
be a corresponding fossiliferous series of normal marine type of sedi-
ments.'^ ^ For salt and gypsum deposits formed as postulated in this
paper this would be true only in part. There would be no fossils in the
contemporaneous deposit, as the waters in the supplying basins were too
highly concentrated to support abundant life, and as the salts were de-
posited Avith great rapidity the clastic deposits would be thin and it
would be difficult, if not impossible, to correlate the salt beds with them.

The accompanying map makes no attempt to postulate the areas of the
overflow basins, but is presented to illustrate the hypothesis. The outline
of the sea and the areas of salt deposits are copied from Schuchert's map
of the Salina Sea.

The Gypsum Deposits of the upper Red Beds of Wyoming

In as far as the writer has been able to learn from the literature and
from his own observations, the gypsum of the upper Red Beds of Wyo-
ming covers an area of some 10,000 square miles. Over about four-fifths
of the area the deposits are thin, probably not averaging over 1 foot in
thickness; over some 2,000 square miles they average 9 or 10 feet, and
over some 200 square miles the beds are 30 to 50 feet thick in widely
scattered patches. The gypsum is remarkably pure and has no salt asso-
ciated with it. The following is a brief statement of the application of
the modified bar hypothesis to these deposits :

1. Original area of isolated sea, 1:0,000 square miles.

2. The average depth of the water necessary was 1,080 feet, but l)asins
500 to 800 feet deeper occurred.

• 3. By the time 80 per cent of the water had been evaporated the area
had decreased to 10,000 square miles.

4. The time necessary for this reduction, with GO inches evaporatiou,
10 inches of rainfall, and 10 inches of inflow, was 260 years.

5. At the time of 3 it is assumed that the water was in isolated lakes,
about four-fifths of it being near the lands to the west and one-fifth to
the east, separated by low barriers from the western lakes. The eastern
lakes had a depth of at least 1,400 feet.

= Principles of stratigraphy, p. 366.

SUMMARY 241

6. The western lake had 5 feet of evaporation and 1 foot of overflow
per year, and this was supplied by 10 inches of rainfall and 5 feet 2
inches of inflow from the drainage basin.

(Note. — With a 15-inch rainfall and 10 inches of run-off, about the
same as the headwaters of the Missouri today, the drainage basin would
luive to be a))out 50,000 square miles in extent, or lialf the size of tbe
State of Wyoming.)

7. The 1 foot of outflow per year from 8,000 square miles would sup-
ply the inner lakes, with an area of 2,000 square miles, with l feet of
water per year; the rainfall would supply 10 inches and the water level
would remain about constant, with an evaporation of 5 feet per year,

8. The concentration in the lakes was about 1 part gypsum to ;)()0
parts water 1)y volume at the end of 3, and 4 feet of watei- coming in
fruni the overflowing lakes would add 1 foot of gypsum every 75 years
to the inner basins, or 5 feet in 375 years.^° Correcting this for the
decrease in concentration of the outer basin waters, it would take about
500 years to add the 5 feet of gypsum.

9. If the inner basin was 1,500 feet deep, there was enough water in
it to supply 5 feet of gypsum. Total of 10 feet of gypsum at the close
of 8.

10. Time for 4, 260 veais; for 8, 500 vears. Total time. :(iO vears.

11. The thin deposits over 8,000 square miles nuiy have originated by
piccipitation from shallow concentrated waters soon after 3 and the pre-
cipitation liave lieen interrupted l)y inflow from riveis.

Summary

Tlic iiiiiiii (liHirult ics in exphiining thii-k ileposits of gypsum were
stated oil ihe lirst page of this paper.

1. The \o!iiiiie of water for the thicknesses of gypsiiin greater than Id
feet is not e.\phiiiie(l hv the pre>eiit h\potheses. excepting h\ having
hasjiis (lee])ei' than 1.5(i() feet or hv ha\iiii; a higher proport idn of caiciiiiii
sulphate to sodimn chh»ri(h': hut it is shown that such (le[)osit- lie in
basins just enough helow the sni KniiKhngs to contain the extra thickness,
and that the givater thickness may have resulted from currents shifting
the unconsolidat('(l i:vp>iiiii aloni;- the bottom.

'"If llic DiiliT liil<cs wcrt' .")(M) feci ilrc|i :inil llhTc \\;iv mu' I'ikiI iif (i\ I'l'lluw per vciir.
Ilicli- wjilfi's WDiild he piaci iciill.v one hair iis ciiiicinlrM led Ml iln- cikI ol' ."lUd vi'ius as at
llif bi'niiiiiliiK. ami iIk' aiiiuinil ul' jiypsuiii cariii'd Im i lif inner liasiiis would Im> tliree-
lOiirtlis as ninili in ."lOli years as il' Ihe cuncen Oa I imi Ilk! remained Ihe same as In the
he^innlnn.

242 E. B. BRANSON THICK GYPSUM AND SALT DEPOSITS

2. The evaporation causing the precipitation of gypsum lies between
.19 and .095, the original volume of sea-water, and the only other salt
precipitated at that stage is CaCOg, which amounts to less than '.] per
cent of the whole.

3. The absence of salt is accounted for by the precipitation being in-
terrupted before the salt stage is reached, either by freshening from the
inflow from rivers, by increase in rainfall, or by the filling of the outer
basins with sediments so that the overflow exceeds that necessary to bal-
ance the evaporation from the inner basins.

4. The absence of sedimentary impurities is explained by the rapid
accmnulation of the deposits and by their having no inflowing streams
bearing sediments.

5. The absence of fossils is due to tlie waters being so highly concen-
trated that life had ceased to exist in them before gypsum began to be
deposited. 'J'he percentage of salt in the water when the first precipita-
tion of gypsum occurred was four-fifths tluit in the waters of the Great
Salt l^ake at the present time and greater than in tlie Great Salt I.ake
when the first analyses were made.

All difficulties mentioned on the second page of this article in explain-
ing thick deposits of almost pure salt are met by the hypothesis :

1. The de])th of water is ample, even in relatively shallow basins.

'2 and 3. The gypsum was precipitated out before salt deposition be-
gan and when the waters occupied much wider areas, and was relatively
unimportant below the salt or might be entirely lacking, as explained on
page 232.

4. Fossils would 1)e absent in the >;ilt jind in tlie sediments associated
with it for the same reasons as, with the uvpsutn.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Vol. 26, pp. 243-254 JUNE 28, 1915

LENGTH AND CHARACTER OF THE EARLIEST INTER-
GLACIAL PERIOD '

BY A. P. COLEMAN

{Read before tJie Society Decemher 30, P.J13)

CONTENTS

Page

Introduotiou 24:)

The Dou bed.s 244

The Scarboro beds 247

Difficulties of Professor Wrighfs iiiteiiiict.ition 248

Interglacial deposits in other places 251

Length of inter-Glacial time 252

Inti.'odiction

The earliest inter-Glacial period known in Canada is l!i:it of the To-
ronto formation, which has heen described more tliaii (Hicc. iind is some-
what well known to Pleistocejie geologists. K.\ca\alions nc;ii' Toronto
and elsewhere provide fresh information in I'cgard lo it fi-itni time to
time and give emphasis to the conclusions already reached as U) its length
and the charactei- ot its climate, and special studies of llic gciu'ral rela-
tionships have been made by the writer in connection with the recent
visit to Toronto oL' the Geological Congress. As there arc still some
|ii'oniiiicnt Pleistocene geologists who refuse to admit an iiiici'-Glaciai
inlerxal of gi-cat length and of mild climalr, it is ])roposi'(l to hi'iiig to-
gctluM' here the latest evidence of the reality and imporlaiiee of ibis iiiter-
Glaeial pei'iod.

\\ Toronto li\c well de!iiie(! sheets o[" boiddei'-elav ai'c knoviii, willi
Tour sheets of interglacial stratilled sand and clay separating them,
'i'liese inlerghu'ial deposits vary from ■'."> to is,") j't'ei in tliickncss and
donbtless represent very dilTei-eiit interval^ (d' lime. In 1 wo of them
fossils have been obtained; but the lowest, ;ind iberefoi'e oldest of lliem

MiiniiMcrlpI riTi'lvid liy llic .SiM-n-iar.v nf ilic Si)i'li'i> .\|iril '_', I'.Ml.

244 A. p. COLEMAN THE EARLIEST INTER-GLACIAL PERIOD

is much the most important in thickness of the deposits and in the
great amount of fossil materials which have been obtained from it. The
lowest of the four interglacial beds only will be considered here. It is
intended to show that the time interval was very much longer than post-
Glacial time, and that the removal of the ice was very widespread, in-
cluding a recession beyond the James Bay slope toward the north. It
is probable that the Toronto inter-Glacial period is the same as the
Aftonian.

The Toronto formation includes two divisions — a lower one, best shown
at the Don Valley brickyard, which may be called the Don stage, and an
upper one, best seen at Scarboro Heights, the Scarboro stage. There is
no unconformity between the two ; but the fossils of the Don indicate a
warmer climate than the present, while tiiose of Scarboro suggest a some-
what cooler climate than the present. However, the fossils of the Scar-
boro beds are not arctic nor subarctic, as might be supposed, but tem-
perate forms. All of the living species represented in the beds are now
inhabitants of southern Ontario. Of the larger number of extinct beetles
little can be said with certainty as to climate. The change of climate
within the time of deposit of the interglacial beds was distinct, but not
extreme.

The Don beds will be taken up first.

The Don Beds

The preglacial surface at Toronto had a somewhat high relief and
was made up, so far as known, of weathered Lorraine shale, more or less
carved into river valleys. The oncoming ice swept otf the weathered ma-
terial, mixing it with solid blocks of shale and limestone, as well as the
varieties of Archean rocks which occur to the north. Granites, green-
stones, and green schists are common, and also well polished and striated
blocks of solid Trenton limestone and smaller fragments of black Utica
shale. No rocks of later formations than the Lorraine have been found,
so that the ice must have advanced from the east or northeast. If it had
come from the northwest or west, one should find fragments of the Red
Medina sandstones or shales or of the Clinton or Magara or Guelph
limestones, all easily recognized rocks; but none have been found. There
should also be blocks of the jasper conglomerate and the red quartzite of
the Huronian region, which likewise have never been fouiul, though tiio
lowest boulder-clay has been carefully studied at more than one point.
The first ice-sheet came, therefore, from the Labrador center, 700 miles

THE DON BEDS

245

away, and not from the Keewatin center, 1,400 miles away, as suggested
by Professor Wright.

The lowest boulder-clay in most parts of the Don A'alley rests on the
Lorraine shale, with a thickness of 3 or i feet ; but at one point, near the
bend of the Don, both the boulder-clay and the shale beneath were cut
away by a small intergiacial river to the depth of 16 feet, over a breadth
of 400 feet. The cutting into the shale, with its resistant layers of thin
limestone, was as deep as that made by the Don in post-Glacial times,
and probably required as long a time to accomplish.

In this old river valley a fairly swift current deposited shingly gravel
made from the underlying shale mixed with leaves, Avood, bark, and other
vegetable material, including wood of the red cedar and pawpaw, showing
that the climate was no longer glacial, but had already become warmer

30\

rr^TTuw ;i ■■■'■fPecgh'?-} \ '-. ■{•■.'■.•.•.'•.■;.•

Don BedsJUnios, etc.)

L orraine

Level o/" Don ff/ver

fiorizon/a/ ySc^e. of feet
<2 £o /j^o

Section at bend of Don
Figure 1. — -Cross-section of the Don Beds

Lorraine

than lliat of Toronto at present, 'i'hei'e are many iiiibrolscn niiios. a.no-
tions, and gastropod shells in the Finer beds above.

At the Don Valley brickyard wood, sometimes as tree trunks 1'^ (u* 15
feet long and still retaining branches, is found flattened into the surface
of the boulder-clay, and many unios arc embedded in a few inches of
clay resting on the till. These shells are often in pairs and are still cov-
ered \vith the greenish epidermis found on living unios in the Don near
by. It is evident that they lived and died on the spot where they are
Pound.

Above the blue clay resting on the till there are well stratified beds of
sand and clay, rising for about 17 feet, laid down in the shallow water of
a lake. They contain many shells, especially unios, sphiBriums, and pleuro-
(teras, seldom broken, thougli many are worn by ihe sand and flue gravel
willi wliich they were deposited. In a few of the thin beds of clay be-

246 A. p. COJvKMAX TlIK EAKLIKST 1 N TKK-f : LA( lAL PERIOD

tween the sand layers there are great numb<^rs of leaves of deciduous trees,
usually perfectly preserved, though hard to extract as complete leaves
because of the difficulty in splitting the clay in precisely the right way to
expose the whole of a leaf. Hundreds of leaves have been obtained, and
most of the 35 species of trees reported from these beds have been deter-
mined from them. The leaves evidently settled to the muddy bottom in
quiet water. They were not crumpled nor wcatlicred nor tmii bei'oi'o
they were embedded, and the organic niattci' is still preserved as a thin
brownish layer.

Above the highly fossiliferous beds there are ;J feet of blue sandy chiy,
with fewer shells, and 5 feet of brown sand which occasionally contains
wood. The brown or yellow sand is more or less cemented witli iron
oxide and must have been formed in shallow water under oxidizing con-
ditions. The whole thickness of beds at the brickyard is about 25 feet,
but including the beds in the old rivei\ channel half a mile east at the
bend of the Don the thickness becomes 40 or 45 feet.

Blue, finely stratified clay, resting evenly on the l)rown sand and rising
for 23 feet at the brickyard, is considered to rei)i'esent the lowest Scar-
boro beds.

The Bon beds occur over almost the wliole area of Toronto and haxc
been found 14 miles to the north at Thoridiill. where wood, a pine cone,
and shells Avere obtained, after penetrating a great thickness of till, in
stratified sand and gravel 200 or 300 feet below the surface. The warm-
climate beds have been found also in a well at Scarboro Heights. 7 miles
east of the Don. The kno«ai width of the l)eds near Lake Ontai-io is l:!
miles, and with a length of 14 miles iidand the area ciin hai-dly he less
than 100 square miles and may be much greater.

The natural explanation of the facts just described is iluil nflei' I he
earliest ice-sheet had withdrawn for ;i limc long enough for a stream to
ciit a valley 16 feet into shale and to allow forest trees like those of Penn-
sylvania to reach the Don Valley, the outlet of the Ontario basin was
slowly lifted, ponding back the waters so as to form a lake, which grad-
ually rose to a height of 50 or 60 feet above that of Lake Ontario. Unios
and other shell-fish, some of them Mississippi forms, throve on the mnddy
bottom ; floating tree trunks got water-logged and sank into the mud, and
all were buried under sand and clay brought by a great river from the
north. Fresh trunks and leaves from trees that grew on the banks of the
river were carried down from time to time during hundreds or thousands
of years, all being quietly entombed in the beds of the growing delta, and
with them were preserved bones and horns or tusks of extinct mammals

THE SCARUOKO BEDS 247

like those found in the Aftoniiui bods. Everything went on quietly and
ill oi-dev. without great floods or catastrophic action ot any kind, and the
whole demanded a warm climate and much time.

The Scakbuko Beds

lasting on the Don beds at Scarboro and elsewhere we find 95 feet of
stratified clav and 55 feet of stratified sand, in which none o£ the warm-
climate wood or leaves have been found. The mud and sand of the delta
brought down from the north by the great river were spread out in the
interglacial lake, which at length rose to 150 feet above the present Lake
Ontario. The mud deposited by the river consisted of thoroughly weath-
ered material from which the lime had been leached, providing clay that
makes bright red brick. The boulder-clay near Toronto is highly charged
with lime, and the stratified glacial clay derived from it above the inter-
glacial beds retains so much lime as to burn to a gray or buff brick, the
red color of the iron oxide being entirely masked by the lime. It is evi-
dent that the country to the north had been long exposed to the weather,
and that no glacier mud was being delivered to the interglacial river or its
ceras, seldom broken though many are worn by the sand and fine gravel
tributaries. There was no ice lurking on this side of the northern water-
shed.

The fossils derived from the Scarboro beds include 72 species of beetles,
of which only two still live. Doctor Scudder, who determined them, says :
"Looking at them as a whole and noting the distribution of the species to
which they seem most nearly related, they are plainly indigenous to the
soil, but would perhaps be thought to have come from a somewhat more
northerly climate than that in which they were found."

The plant remains are on the whole less satisfactory for dclerminatinii
than, the trees of the Don beds. Among trees, Lari.r anwricana, Abies
halsaniea, Picea, Salix, and AIniis have been determined : anu)ng smaller
plants, Oxycoccus vulgaris and \'acriniuni uliginosum are mentioned by
Docfor Macoun. A large number of seeds are found in the peaty matter,
and Dr. W. L. McAtee^ has determined from them Scirpus fliiviatilis,
Potainogeton sp., Hrasenia purpurea, Prunus, probably Pennsylvanica,
Pofi/gonuni, sp., ChenopodiiLvi sp., and CpratopliyUuiii deiiiorsuni. A
number of species f»f mosses have been obtained also. Doctor Macoun.
wlio determined Ihc upper part of the list, believes that the climate was
like that of the northern part of Ihe Oulf of Sainl Law icnre or southern

= r. S. Biolofdcal Survey. Washin^'ton, D. C.

248 A. p. COLEMAN TPIE EARLIEST IXTER-GLACIAL PERIOD

Labrador, cool and wet; but all the plants he mentioned still live in
swamps to the north of Toronto and all the trees occair at Toronto. The
plants determined from the seeds indicate a climate like the present, as
all of them are found here now, and most of them extend much to the
south of Toronto. The later evidence just given modifies considerably
the conclusion reached by Dootor Macoun, and I am told by botanists
that northern forms are often found in peat-bogs or swamps far soutli of
their usual habitat. In general, it may be said that the climate of Scar-
boro times was distinctly cooler than that of the Don beds and probabl)'
somewhat cooler than that of the present, but that it was far remo\e(l
from arctic conditions.

Difficulties of Pkofessoe AVtugiit's Intekpketation

Prof. G. F. Wright, who has visited the sections at the Don and St-ar-
boro, does not accept the interpretation given in the foregoing pages, and
suggests another way of accounting for the facts by which the inter-
Glacial interval is to be eliminated and the whole series of events is to be
condensed into the briefest possible time, apparently a few thousand
years. The mechanism by which he would accomplish this is not entirely
evident to the present writer, but the following ideas seem to cover the
essential points:

1. The lowest boulder-clay at the Don was not formed by ice from the
Labrador center, but by an advance from the Keewatin center to the
northwest. This has been shown to be incorrect.

2. The supposed warm-climate beds, admitted by Professor Wright to
imlicate a climate warmer than the present, consist of materials dej)osit('(i
in late Tertiary times, transported from somewhere by mysterious nutans
and placed gently and deceptively on the lowest boulder-clay. He thinks
that the specimens of warm s]iecies of plants and animals may have been
'^ploughed up by a readvance of the ice after a temporary recession and
raised without much disturbance to the higher beds where they are now
found." He supports this view by a reference to the well known but still
enigmatic Moel Tryfaen deposits in Wales, where marine shells are sup-
posed to have been lifted by the ice and afterward laid down in beds of
stratified sand. He says that in a few hours several whole shells could
be found, though "most of the specimens are fragmentary."

Apparently some doubts existed in his mind as to whether the innu-
merable whole shells, with no broken frag-ments, and the hundreds of
perfectly preserved leaves in the Don beds could have reached their pres-

DIFFICILTIKS OK PROFESSOR WRIGHT's INTERPRETATION 249

ent position in this way, for he refers later to the great masses of chalk
in Sweden, one of them 3 miles long, 1,000 feet wide, and 100 or 200 feet
thick, shifted by the ice and now inclosed above and below by glacial
materials.

Tertiary beds have not yet been found in Ontario from which the warm-
climate fossils of the interglacial could be derived, and in any case it is
incredible that the 100 square miles of fossiliferous deposits should not
somewhere show evidence of the strange history they are supposed to have
passed through. The interglacial leaves and shells, all whole and sound,
could not have survived the Moel Tryfaen experience, in which the great
majority of the shells were broken ; and Professor Wright will hardly
suggest that a sheet of sand and clay 100 square miles in area could be
transported bodily for an unknown distance to be laid gently on the lower
bed of boulder-clay. The immense disturbance must somewhere have left
its marks.

Even if this extraordinary theory were accepted the real difficulty has
not been touched, for it has been shown that the warm-climate beds are
buried conformably by the later Scarboro beds. If the Don ])eds were
shifted bodily, they could hardly be laid down so evenly that the delta
clavs and sands of the Scarboi'O stage should not show some unconformity.
If it be suggested that the whole series, including both Don and Scarboro
beds, was shifted together, the difficulty of transport is still further in-
creased, since the Scarboro beds have a width of 35 miles as compared
with the 13 miles of the Don beds, and the area of flat, undisturbed clay
and sand to be transported is increased to probably 150 or 1?5 square
miles.

However, it is prol)able that Professor Wright had no such thought in
mind, since in his concluding statements he suggests that the Keewatin
(rlacier extended in the vicinity of Toronto into a region "occupied by
some species of piants and iininials which now exist only at a considerable
distance to the south. At that time the lower Don beds were fomied.
Later the Labrador rilacier pushed outward as the Keewatin Glacier re-
ceded. . . . During this advance over the deserted Keewatin deposits
in the vicinity of Toronto, the Scarboro beds, overlying the Don beds,
were deposited and some of the fossil plants and animals native to the
lower beds were incorporated into the lower portions of the upper beds."

How this is to be reconciled with the drainage of the interglacial waters
to a depth below that of Tjakc Ontario, as ])roved by the Dutch Church
Valley, at Scarboro is iuird to see. This interglacial valley, a mile wide
and 166 feet deep, could not have been carved while the Labrador ice-

XXIX — Bri.i,. Gkou Soc, .V.m., Vol,. 20, lOH

250 A. p. COLEMAN THE EARLIEST INTER-GLACIAL PERIOD

INTERGLACIAL B£.D3

IN
ONTAf^/O

Scale,
/oo mi Iks

Figure 2. — MaiJ shoicing interglacial lieds in Ontario

DEPOSITS IN OTHER PLACES 251

sheet blocked the Saint Lawrence. This theory ignores also the fact that
later ice-advances — for instance, the Wisconsin — passed right across the
interglacial beds, filled the Ontario basin, and spread out a sheet of till
and a series of moraines in the States to the south.

Interglacial Deposits in other Places

The case for a great inter-Glacial period in the early Pleistocene is,
however, much stronger than even the beds at the Don and Scarboro
would suggest, for there is evidence to show that similar beds are much
more widely distributed. Land and fresh-water shells occur in thick
interglacial beds at the west end of Lake Erie,^ and certain beetle-bearing
peaty clays at Cleveland, Ohio, are precisely like those of Scarboro, and
include two of the extinct species found at Scarboro, while leaves of
maple and other trees have been obtained in interglacial beds north of
Lake Erie near Port Eowan. Interglacial wood has been found beneath
boulder-clay by Doctor Spencer near the bottom of the ancient Saint
Davids Valley west of the Whirlpool at Niagara, and Miss Maury has
described an interglacial bed near Cayuga Lake, 'New York, containing
eleven of the unios, sphaeriums, and other shells of the Don beds. This
interglacial stage has left its mark on both sides of the two southern great
lakes at points 300 miles apart.

A series of interglacial deposits 350 to 400 miles to the north of To-
ronto presents much the same character. The flattened trunks of trees
and the peaty matter are closely like those from the Don. No less than
27 outcrops of lignite or peat of this kind are found in the river valleys
of the James Bay slope, extending for 150 miles from east to west and
for 50 from north to south. The climate in that northern region was
mild enough for trees of large size to mature, and Professor Baker, the
latest geologist to report on the region, believes that there was time
enough for the vegetable matter to be buried and thoroughly carbonized
before the next glariation.* Either the ice retreated more than 400 miles
beyond Toronto or the ()])ponents of inter-Glacial periods have a second
important inter-Glacial interval to account for. That the two sets of de-
posits, each demanding a great length of time, were formed contempora-
neously seems most probable.

■'' GeoIoL'icjil Siirvrv ul' (•iiiiiiilii. M)l. xlv. I!>(i1. |i. ]C,f<. A s\iminary report by Doctur
Chalmers.

♦Bureau of Mines. <»nt!iri<,. vol. xx. imrt 1. pp. :i:i4-2."{S. r>etalls of authorllles for

pi'evlously mentioned localities iii!i.\ he found In "An estimate of post-Olaelal nnfl Inter-

Olac'lal time in North .Vmcrica." n piiper presented to the (Joolopical Conpress.

252 A. 1'. COLEMAN THE EARLIEST J XT1':H-(;LA< ] AL PERIOD

There are reasons also for thinking that tlie Aftonian beds of Oliio and
adjacent States are of the same age. In both cases there is only one slieel
of bonlder-clay beneath, while there are four, separated by layers of iiitcr-
glacial materials, above. All of the genera of trees mentioned in ila-
Aftonian occur in the Toronto formation, and probably all but oue of the
seven mammals found at I'oronto are of the same genera as Aftonian
mammals. The Ohio region has mostly been glaciated by ice-sheets com-
ing from the Keewatin center, and if we correlate the Toronto and Afto-
nian formations it implies that the ice-sheets of the two centers had
parallel histories, which seems highly probable.

Length of inter-Glaciat. Time

The total length of the earliest inter-Glacial interval must haw been
far greater than that of post-Glacial time. It begins, as shown in the
Toronto region, with a period of. river erosion comparable to that needed
by the Don to cut its channel since the ice departed ; is continued by the
deposit of delta materials to the depth of 185 feet, reqtiiring thousands
of years, and ends with the cutting of river valleys much more mature
than the postglacial valleys. Attempts have been made to estimate these
different processes with the general result of tripling or quadrupling post-
Glacial time. Tn a jiaper read by the present writer before the Geological
Congress it has been shown from the rate of recession of Scarboro Heights
through wave erosion that Lake Ontario is at least 8,000 years old. This
result is corroborated by the rate of building of Toronto Island, which is
formed of materials transported from Scarboro. The method of calcula-
tion is far more definite and accurate than estimates formed from the
dunes of southern Lake Michigan.

The 8,000 years reqttired by Lake Ontario to give its shores their pres-
ent development must have been required also by Lake Iroquois, with
shores of equal maturity. The marine episode coming between the two
and certain preliminary stages of the two lakes not included in the time
required to form their present shores probably demand an equal amount
of time. The whole time since the ice left the Ontario basin can hardly
be less than 25,000 years.

This estimate, which is based on definitely measured factors and is not
merely a guess, gives a fair idea of post-Glacial time, probably under
rather than over the true amount, and may be used as a measure for cer-
tain interglacial phenomena. The preliminary stages of the inter-Glacial,
including the cutting of a river valley 16 feet into shale, may be esti-

LENGTH OF INTER-GLACIAL TIME

253

mated as equal to post-Cllacial time, say 25,UOO years. Tlie deposit of the
interglacial beds, checked by the counting of 672 annual layers of clay
in a thickness of 19 feet G inches, is considered to have required not less
than 4,300 years. The broad, gently sloping interglacial valley of the
Dutch church at Scarboro required for its formation a time much greater
than the far less mature postglacial valleys. If we say only twice as much,
50,000 years. The wliolc of the inter-Glacial interval must liave been
75,000 or 100,000 years in length.

Even if the much too sliort estimate of post-Glacial time given by Pro-
fessor Wright — 10,000 years — is employed in computing the length of the

Section of Don valley; narrow part

Section of Don valley; wide part

Level of

LaHe Ontario

Section of interglacial valley; Dutch church

ScaJe of Fee A

O lOO

I I — i — 1 — I — I — I—

/ooo

l_l

l''i(:r];i-; ;{. — Si'cliuiix nf iiiti'iiiliuiul iiiiil iKixhjhiiiiit \ itlleijH

inter-({lacial period, il amounts to 3-1,000 years. From the evidence as
to climate given above it can not be denied that as high a temperature
existed both at Toronto and on the James Bay slope in inter-Glacial times
as now. The Labrador ice-sheet, which centered only 300 miles northeast
of tlic James Bay lignite deposits, docs not exist now and could not exist
in the equally warm or j)robably warmer inter-Glacial time. If the great-
est of all the ice-sheets, that of Labrador, was melted in the earliest inter-
Glacial j)rrii>d. what iiic the probabilities in I'egai'd to ihe smalK-r ice-shee!
fore.st growth ;it least us i-icli as the |ii'c<cnl on the west sitU" of James
Bay? Tt seems higidy improbable tliiil the Keewatin ice coidd survixe a

254 A. p. COLEMAN THE EARLIEST INTER-GLAClAL PERIOD

climate like the present for more thousands of years than have elapsed
since the end of the Glacial period, and we may conclude that during the
earliest inter-Glacial time no ice-sheets remained in North America except
alpine glaciers on the loftier mountains of the west.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA
Vol. 26, pp. 255-286 JUNE 29, 1915

OBSIDIAN FEOM HRAFNTINNUHEYGaUR, ICELAND: ITS
LITHOPHYS.'?] AND SURFACE MARKINGS '

]SY FRED. E. WRIGHT
(Preaenlfil in abstract before the Society Deceinljer SO. 1000)

CONTENTS

Page

Historical review 255

The Hrafntinnuliryggur ob.sidian 258

General description 258

Chemical characteristics 259

Spherulites and lithophysse 262

Secondary minerals and etching phenomena produced by hot circulat-
ing solutions 275

The moldavites 280

Summary 285

Historical Review

To the student of rocks the forms and relations of crystals and of
cr\^stal aggregates precipitated from a cooling magma are in large meas-
ure the expression of the physical conditions under which the magma
solidified. This was thoroughly appreciated by the' pioneers in petrology,
who observed that as the physical conditions of freezing of such magmas
varied, so also did the resulting products of crystallization, with respect
both to the kinds of crystals formed (mineral composition) and to the
habits and relations between the crystals (rock texture). Of the differ-
ent kinds of crystals thus studied none has received more attention tliaii
tlie sphoi'ulites; and yet oiii- knowledge of them is still iiuomplete, espe-
cially of the hollow spherulites or lithophysse, the best examples of which
have been roniid in llic obsidian of Yellowstone National Pai'k. These
were studied many years ngo by Tddings^ in detail and with special rtWcr-
ence to their mode of formation. At that time petrologists wi'ic mil

' Mamiscripi i-ccclvcd li.\ tlif Secret a r.\' i>r llif Society .\\iyi\ l;0, ini.'i.
- T'. S. f!e(>li>ulc;il .Siirvi'.v, Seventh .\nn. lieport, ISS.'i. pp. L'."i:!-i!0;"i.

{ 255 )

'2'A') v. K. WRKUIT OBSIDIAN FROM ICELAND

ill accord as to the genesis of the lithophysae. Yon Eichthofen had
•suggested in 1860 the name Lithophysen' (Greek Xl6o<;, stone, and <l>vaa,
■l)ubhle) for the hollow spherulites m the Hungarian rhyolites, on the
assumption that their formation is due to the expansion of gas bubbles
which, liberated during the crystallization of tlie spherulites, are unable
to escape from the viscous magiiia and lience force out the walls of a
cavity, each successive bubble carrying a thin film (bubble) or shell of
the magma into the cavity, and thus producing the concentric structure.
During this process chemical reactions between the gases and the crystal-
lized material of the spherulites take place and cause solution, reciys-
tallization, and a general rearrangement of the original material pre-
cipitated from the magma. Zirkel'* in 1876 practically adopted von
liichthofen's hypothesis of chemical alteration. S. Szabo'^ and Eoth,*^ on
'the other hand, considered that the lithophysa^ are tlie result of chemical
and mechanical alteration of solid spherulites, the solul)le portions being
removed chemically, the insoluble mechanically, with the exception of
silica, which constitutes the major part of the lithophysa?. This view
involves transfer of material away from the cavity, wJiile according to
von -Richtliorcirs idea there is no such transfer, only rearrangement
within the cavity. Still other views were held by von Hauer' and AVeiss,®
Avho considered that lithophysai are linllow s])h('rnlit('s fdrnicd about the
gas bubbles which escape from th(> coDJiiig mauina. ('I'oss" concluded
from his study of litho])hysa? that the minerals. t()])az and garnet, which
occur therein, were '"produced by sublimation or crystallization from pre-
sumably heated solutions, contemporaneous or nearlv so with the final
consolidation of the rock. The litho])hysal cavities seem plainly caused
by the ex])ansive tendency of confined gases or \apois. while the shrinkage
cracks in the walls and white masses of (he Xathvo]-) I'ock suggest the
former presence of juoisture."

Iddings found "that the lithophysae in the obsidian of Obsidian Cliff,
with their contents of prismatic quartz, tridyniite, adnlar-like and tabular
soda-orthoclase, magnetite and well ciwstallized fayalite, are of aqueo-
igneous origin, and result from the action of absorbed vapors on the
molten glass from which they were liberated during the jirocess of crvs-
tallization consequent upon cooling."" An arching of the la vers around

3 Jahrb., K. K. Geol. Reichsanstalt, vol. 11. 1860. p. 181.

^ tT. S. Geol. BxpL. 40th Parallel, vol. 6 ; Microscop. Petrography, 1876. p. 212.

= Jahrb., K. K. Geol. Reichsanstalt, vol. 16, ISGfi. p. S9.

" Beitrage zur Petrographie der pliitonischeu Gesteine. 1860. p. 16S.

' Verhandl. K. K. Geol. Reichsanstalt. 1866, p. 08.

8 Zeltschr. Deutsch. geol. Gesellschaft, vol. 20. 1877. p. 418.

»Am. .Tour. Sci. (3), vol. 31, 1886. p. 432.

HISTORICAL REVIEW 257

a lithoi^liysa occurs fiequently, and ''at first sight il would secui tliat the
expansion of a huhl)le of gas vvitliin the hiva had occasioned the distention
or displacement of its layers ; hut a cai-eful study of portions of the rock
which exhihit great distortion and plication of the layers makes it evident
that in these cases the hollows occur beneath arches in the folds where
there has been a local relief or diminution of pressure, which might allow
the absorbed vapors to disengage themselves and to bi'ing about the con-
ditions M'hich produce hollow lithophysae in connection with spherulite
development. In other words, the arching of the layers appears to have
been the cause of the liberation of gases and the production of the cavity
beneath, and not the result of expanding gases." The observed relations
"leave no doubt that the spherulites and lithophysa% in all their com-
plexity of form and structure, are of primary crystallization out of a
molten glass, which was gradually cooling and consolidating, and that,
since its solidification, no alteration, chemical or mechanical, has taken
place/'

The work of Tddings on the Obsidian Cliff spherulites was so thorough
and convincing that his conclusions ha\t' since l)c('ii Mcccptcd and applied
without resei've to all lithophysa'. In one particnlai', however, this gen-
eralization of the conclusions which hold primarily for the Obsidian Cliff
rocks may not be warranted, namely, that in the formation of the cavities
the expansion oi' the liberated gas plays no significant role. For the
Obsidian Cliff lithophysa^ the evidence proljably justilie(| the position
taken by Iddings, that the cavities were formed 1)\ a kind of uniform
tension in the viscous, cooling, and contracting magma (just as joints
are formed in a later stage of cooling), and that at such ])oints crys-
tallization liegjin and was accom])anied by escape of gas into the cavity.
I)ut it is also ))()Ssible that in other localities, as a lesult of slightly
dilTei-ent conditions, the pi-essui'e of the escaping gas was a factor not
only in enlarging the cavity, t)ut also in its initial rormation. We have
thus two ditt'erent hypotheses available: at the one exlrenie we lind the
total effect ascribed to hydrostatic tension or uniform pull developed by
the shrinking of the magma during cooling: at the other, to the pressure
of the gases set fi'ee on crystallization of the spherulites. In most cases
it is pidhahle that both factors, contraction of the cooling magma and
gas pres-iure, have been active. The primary purpose of the ])resent
paper is to piesent e\ idence that in the case of the Icelandic lithophySiV
the pri'<surc of the liberated gas was an important factor in the deveIo[)-
meiil (if the ca\ities. Incidentally the oiigin of certain etched surfaces
ol ol)>idian which i'e<ciuhle mol(la\ilic markiiiLis will he cmisiilered.

258 f, e. wright obsidian from iceland

'I'he Hrafntinnuhryggur Obsjutan
general description

The obsidian specimens containing the litliopiiysae were collected by
the writer in 1909. Unfortunately lack of time and of transportation
facilities permitted neither adequate field study of the occurrence nor
the collection of a representative set of specimens. Only a few interest-
ing random specimens were gathered to illustrate, as well as possible,
the different types which occur.

The obsidian of Hrafntinnuhryggur forms a well developed, long ridge
southeast of the volcano Krafla. It is not uniform in structure through-
out, but ranges from dense black glass to a rock approaching pumice.
Banding caused by an alternation of layers of the dense black glass with
bands of semi-pumiceous or spherulitic material is characteristic of cer-
tain of the specimens. Near the west end of the ridge a small circular
pond, resembling a shallow crater lake, occurs; and there the rock is
apparently a breccia consisting of fragments of black obsidian glass
(showing remarkable etched surfaces, which resemble those of the Bo-
hemian moldavites and of certain desert rocks with etched surfaces) and
of a white crypto-crystalline, siliceous substance.

The obsidian proper is a dense, black, brittle glass, remarkably uniform
in character. Prismatic jointing was observed at several points and is
of the ordinar}- columnar type. The obsidian glass takes a good optical
polish, has a refractive index of about 1.500, and might possibly l)e
serviceable as a source of material for making large telescope reflectors;
its coefficient of expansion is probably low, in vieAv of the high silica con-
tent. The fracture is conchoidal; in tlie field a single sharp l)low of the
hammer on a large uniform block a meter in diameter ma}" spall off
ashlars or shell-like pieces, which show most beautiful conchoidal frac-
ture lines. The development of the two sets of lines — the one set con-
centric and emanating like wave-ripples from the point at which the
blow was struck, the second set radiating from it in lines normal to the
first — is so perfect and fascinating that the lack of transportation facili-
ties is keenly felt by the geologist.

Under the microscope the obsidian glass is seen to l)e full of verv
minute crystallites of a colorless, prismatic mineral, not over 0.005 mm.
in length and less than 0.002 mm. in width. The optical properties
which could be determined on this mineral are : Eefractive index, notice-
ably higher than that of the glass; birefringence, medium; extinction,
apparently parallel to the elongation (=y'). These properties are un-
fortunately not sufficient to identify the substance, but other and more

GENERAL DESCRIPTION 259

precise data could not be obtained on the fine particles. Occasional
minute, elongated bubbles (up to 0.05 mm. in length) were also observed.
The density (referred to water at 4° C. and to vacuum) of the obsidian
is 2.387.

CHEMICAL CHARACTERISTICS

For the chemical analysis of the black obsidian I am indebted to Mr.
J. B. Ferguson, of the Geophysical Laboratory, and express herewith my
appreciation of his kindness. The material selected for analysis was part
of specimen 88428," a jet black glass free from spherulites and litlio-
[)hys8e, but containing many of the minute crystallites noted above. The
analysis is that of a fairly normal rhyolitic obsidian. Interesting and
important is the presence of CI and SO3 in appreciable amounts. It will
be shown later that the release of these volatile components in the magma
had much to do with the formation of the lithophysae, while the character
of the physico-chemical system thus produced caused the simultaneous
formation of crystals of fayalite and of tridymite at relatively low tem-
peratures. This mineral association is not that of ordinary igneous
I'ocks or lavas, but seems to be characteristic of lithophysae in obsidian,
notwithstanding the low content in oxides of iron (from 3 to 4 per cent).
'I'll us in 1827 Gustav Rose discovered fayalite and tridymite in the litho-
physae of the obsidian from Cerro de las Navajas (analysis VT : FeO -j-
Fe2O3 = 2.20 per cent) ; in 1885 Iddings found fayalite under similar
conditions in the lithophysa} of Obsidian (Tiff, Yellowstone National
Park (analysis IV; FeO + Fe.Og = l.(iH per cent).

The occurrence of an orthosilicate like olivine with tridymite is rare,
if not unknown, in intrusive rocks. It is less rare in ciriisive rocks and
indicates that physico-chemical conditions of equilibrium at the time of
formation of the crystals may be very different even for magmas of the
same general total chemical composition. The computed noi'mative c<mi-
position in such cases would be the same, but the actual modal composi-
tion may be totally different, thus emphasizing the difficulty of setting
ii|) a pioper normative composition which even approximates the actual
minerid composition of the i-ock.

'"The specimens described iu this paper have been deposited in the V. S. National
.Muiieiim ; the nuniher of the si)ecinien is, in eacli case, its cataloffiie number In the
National Museum.

200

K. E. WRIGHT OHSIDIAK FROM ICELAND

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CHEMICAL ANALYSES

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262 r. E. WRIGHT OBSIDIAN FROM ICELAND

A comparison of these analyses, and especially of the norms computed
from them according to the methods proposed by Cross, Iddings, Pirsson,
and Wasliington, shows that they are all of the same general character.
The Icelandic rocks contain a slightly larger amount of femic minerals
than the other rocks, but the amount is not sufficient to place them in
another class. It is interesting also to note that the analysis 2, by
Bunsen, in 1851, agrees fairly well with the modern analysis 1 of the same
rock. In the legend of the table of analyses the symbols, according to
the quantitatiye classification of rocks proposed by Cross, Iddings, Pirs-
son, and Washing-ton, are given. These symbols show that in nearly
every case the rocks are located near the boundaries of the various sub-
divisions of the quantitative system.

If the obsidian of Hrafntinnuhryggiir had crystallized under the
jjhysico-cheniical conditions of a deep-seated rock, the mineral composition
would probably have been : Quartz, about 40 per cent : orthoclase, about
16 per cent; oligoclase of average composition, AbgAnj, about 35 per cent
(some of the albite substance would probably enter into solid solution
with the orthoclase, Ijut to what extent can not be predicted because of
lack of information regarding these physico-chemical systems) ; aluminous
amphibole. 6 per cent; titaniferous magnetite, 2 per cent, and a little
apatite. The salts, XagCL and NaoSO^, indicated in the norm would
probably l)e carried away in solution as part of the more soluble portion/
of the magma. It is, moreover, evident that the sodium would not be
the only base in combination with these acid radicles as postulated in the
norm. On the whole, experience has shown that in this persalane class
of rocks the modal composition is not greatly different from the computed
normative composition,

SPHERULITES AND LITHOPHYSM

Attention has been given in the preceding paragraphs to the intimate
relation between spherulites and lithophysae and to the several different
hypotheses which have been offered to explain the development of litho-
pliysffi. In the Hrafntinnuhryggur oljsidian all possible gradations oc-
cur between typical, compact, lithoid spherulites and typical lithophysae
with walls lined with minute crystallites, water-clear and very fragile.
Pumiceous structures are also of common occurrence, but they are usually
confined to definite bands and patches which alternate with streaks of
black obsidian glass containing occasional large vesicular cavities. In
the case of a wide band of glass these large cavities are more abundant
in the immediate vicinity of the pumiceous layers and virtually disappear
within a few centimeters. The gas cavities in both the pumiceous and

SPHERULITES AND LITHOPHYSvE 263

adjacent bands are not spherical l)ut tiiinilar in shape, the direction of
elongation being that of the lines of flow of the lava. This indicates
that the lava during the period of its final flow was sufficiently viscous
to prevent the escape of the free gas bubbles which it inclosed. The
restriction of the gas bubbles to definite bands and parts of the mass
might be considered to indicate that during the period of its flow^ the
lava encountered physical conditions of such nature (especially release
of pressure) that certain bands became supersaturated with volatile com-
ponents, which were then released and formed bubbles. These could not
migrate through the lava to any great extent because of its high viscosity.
It is, however, conceivable and a priori more probable that the appearance
of a pumiceous band is not the result of direct evolution of gas from that
band alone, but that either before or during the eruption of the molten
obsidian there was an accumulation of gas bubbles at certain points
(magma hotter and less viscous, thus allowing freer circulation and con-
centration of evolved gas bubbles at favorable pockets near the margin
of the magma chamber), and that on final outflow of the obsidian these
foamy portions of the lava were drawn out and appear now as vesicular
streaks, which serve to emphasize the lines of stiff viscous flow of tlie
lava. On this hypothesis the amount of pumice accompanying a rhyolitic
flow can not be considered to be indicative of the amount of gas given
off by the obsidian. Most of the gas thus liberated from the solution no
doubt escaped, and that which produced the pumice represents only a
small part of the total amount contained originally in the molten ob-
sidian.

Passing now to the spherulites, we find that they occur in typical de-
velopment in several of the specimens. They range in size from a few
tenths of a millimeter to over 5 millimeters in diameter. In the outcrop
they are not evenly distributed through the rock mass, but are confined
to certain bands or layers, thus indicating that in these bands crystalliza-
tion took place more rapidly than in others. In the case of finely lami-
nated floM' banding, however, the spherulites cut across the banding. In
no case was a suggestion of flow banding around a spherulite observed :
this would occur were the spherulites older than the banding. In one
instance the wall of a hollow spherulite was serrated as the result of a
difference in behavior of the different bands with respect to crystallization
and to attack by the volatile components released during the crystalliza-
tion of the spherulite.

The relations outlined above suggest that the determinative factors in
the development of the dift'erent structures which are now found in the
obsidian — ])umiceous, spherulitic. and litliophysal — were the physical con-

264 F. E. WEIGHT OBSIDIAN FROM ICELAND

ditions of cooling- of tlie different parts of the lava, together with tlio
amount and character of the vohitile components dissolved in it. I ii
order to show this clearly, six of the specimens collected at Hrat'nlin-
nuhrvo-yur will be brieflv described.

Specimen 88428 is a black compact obsidian glass, free from s])hcru-
lites. but containing fine hairlike crystallites and minute bubbles 0.05
mm. in maximal length; also dark opaque grains scattered through it.
Part of this specimen served for chemical analysis I and is described in
sufficient detail above.

Specimen 88429 shows clearly the passage of obsidian glass to pumice.
One end of the specimen is typical pumice, with silvery luster in the
direction of elongation of the vesicles; the opposite end is of massive
obsidian glass, with only occasional large cavities, which trend either
approximately i)arallel with or transverse to the general lines of flow.
The transverse cavities are much larger than the others and appear to
be of the nature of rupture fissures — rather than elongated gas cavities —
produced during the final stages of the cooling and flow of the lava as a
result of the tensional stresses thereby developed.

Specimen 88430 presents another structural type whiih was developed
during the period of cooling of the lava. Dull gray-black litlioidal
bands and irregular masses alternate with bands and patches of black
obsidian glass. The lusterless parts consist of spherulites which have
crystallized from the glass. Under the microscope these sphendites are
seen to be of two different types :

(1) Typical radial spherulites, with Hbers radiating from a central
point, or more commonly from a minute central bul^ble. The elonga-
tion of the fibers is a' : a distinct cross is visible between crossed nicols.'
The refractive indices are difficult to obtain accurately, l)ut they lie be-
tween 1.520 and 1.54(». The birefringence is medium to weak. Between
many of the fibers are minute irregular cavities which greatly decrease
the transparency of the spherulites. The determinations indicate that
these spherulites are chiefly albite, with possildy a little admixed ]wfash
feldsi")ar and also free quartz.

(2) Adjoining the radial spherulites are usually patches of substances
of a deeper brown color and of slightly stronger birefringence and less
pronounced radial spherulitic development. The elongation of the fibers
in this material is not pronounced, but in those cases in which an elonga-
tion was apparent its character was y'. The development approaches
that of an aggregate of overlapping crystallites and grains too fine and
too intimately intergrown for satisfactory determination. The refrac-

spm?:ri:lites and lithoimiys/E - 265

five index is about 1.54. It is probable that these spherulites consist
chiefly of quartz intergro^^^l witli some alkali-feldspar.

Not all of the spherulites in this specimen are entirely compact and
gray-black in color. Portions of many of them are porous and then
usually lighter in color and coarser grained. The appearance of such
spherulites leads one to infer that gas was evolved during their crystalli-
zation, and that the volatile components thus set free acted on the spheru-
litic material of the walls and caused its recrystallization. In other
words, each little spherulite, with its portion of volatile components,
which were liberated during its crystallization and were inclosed in the
thick viscous hot glass, may be likened to a chemical flask filled with
appropriate reagents and crystal compounds and heated to such a tem-
perature that certain chemical reactions take place. It is evident that
the physico-chemical equilibrium conditions during the partial crystalli-
zation of a melted magma, from which appreciable amounts of volatile
components are being liberated, are difl^erent from the equilibrium con-
ditions obtaining in a system of the same total composition, but at a
much lower temperature and containing the volatile components chiefly
as vapor phases and the other components as crystallized units. The
result of this shift in distribution of the elements from a homogeneous
solution (magma) crystallizing at high temperatures to a heterogeneous
system consisting of solid and vapor phases held at a lower temperature
is a redistribution of the constituents in the solid phases, such that the
mineral association which we encounter in the normally crystallizerl com-
])act spherulites or in rhyolite or in granite is different from that of the
liollow spherulites or lithophyste. This difference will appear more clearly
ill the descriptions below, l)ut it is essential that the fundamental difPer-
t'licc ill behavior and in stability relations of the two cases be emphasized.

[n certain bands of this specimen the aggregate volume of the gas
cavities is relatively large, but they are not elongated as in specimen
SS429 and lia\(' the ap[)earance rather of a spongy structure. The cavi-
ties here are associated with the spherulites and were evidently developed
in situ.

In one larger cavity a white coating of clear, secondary hyalite was ob-
served. This, mineral is abundant in the more altered specimens of
obsidian and pumice, especially in the specimens gathered at the small
circular pond mentioned above. At this place highly siliceous solutions
were evidently active and not only deposited hyalite but also alunite, and
corroded the black obsidian glass in a remarkable manner, so that many
of the fragments resemble in outer forms the Bohemian moldavites,

XX — lili.i.. <;i;n[,. Siir. A.M., Vol.. JC, 11114

266

F. E. WRIGHT OBSIDIAN FROM ICELAND

whose origin is still in some doubt. The formation of these surface

markings is discussed in a separate section below.

Specimen 88432, as shown
in figure 1, is filled Avith
spherulites, ranging in size
from mere specks to kernels
half a centimeter in diam-
eter. The radial spheru-
lites are usuall}^ white, as a
result evidently of the ac-
tion of the circulating solu-
tions whicli deposited the
alunite and hyalite in the
adjoining gas cavities. The
central part of many of the
radial spherulites is still
dark gray and unaltered.
Under the microscope the
secondary alteration is seen
to be of the nature of a
bleaching effect rather than
of complete recrystalliza-
tion

Figure 1. — Oisidiaii coutuininu rudUiJ S/tJieni-

lites and buhble Cavities

Specimen 88432. Two-thirds natural size

although there is evi-

dence of partial recrystallization.
Specimen 88433. — In this
specimen there are iiumerous cav-
ities (0.5 to S mm. in diameter)
partly filled witb crystal fibers
which radiate from the walls to-
ward the center. They vary in
size and often in shape ; but when
undisturbed by adjacent cavities
they are roughly spherical in out-
line. On breaking open the cav-
ities, one is impressed by the fact
that the crystallized material does
not completely fill them (figure
2) ; also that the crystals in the center of the cavity are coarser than those
at the margins. The radial fibers are usually water-clear, and are capped
and studded -with tridymite crystals in twinned groups measuring up to

FiGfRK 2. — fjithophysw iritli flitted Tongue of
Obsidian projecting into hoUoic Caritji.
shown in Center of Photofjraijh

Specimen 88433. Magnification, 15 X

SPHERULITES AND LITHOPHYS^E

267

0.5 mm. in diameter. The supporting needles rarely measure over 0.03
mm. in thickness (see figure 3) . Their optical properties, so far as could be
determined, are: y about 1.535, a about 1.530; birefringence weak: ex-
tinction oblique with c:y' from 0° to 28°; elongation is usually y', but
occasionally a. The plane of optic axes is apparently normal to the
elongation. Some of the needles have the appearance, between crossed
nicols, of 23ossessing exceedingly fine polysynthetic twinning. It was
thought at first that this mineral was albitic plagioclase, but several of
the above optical properties do not agree with those of albite and it is
not certain that the mineral is a feldspar. The composition of the ob-
sidian itself would indicate a feldspar. The tridymite has the usual

^f^'^^^y^*"

\ ' •

"iL.T"^

Fi'Jiiiu:' ;?. -Tridymite Crystals supported by Needles uf Feldspar (?) in recrystaUized

Lithophysa

Specimen 88433. Magnification, 50 X

characteristics: Tabular plates and thick prisms hexagonal in outline;
weakly birefracting in irregular fine patches; refractive index slightly
less than 1.480; plates grouped in characteristic twinned aggregates.

The aspect of these lithophysal minerals and the manner of their
grouping: are such as to render untenable the hypothesis that they were
crystallized directly from the cooling niagma. A comparison of the
lithophys83 of this specimen with the radial spherulites and the incipient
lithophysiv of the specimens described above shows that the lithophysse
were origijially spherulites with a gas cavity, but that they have been
partly, and in some instances entire!}', recrystaUized by the action of the
vulaliltj components of the cavity at relatively high temperatures, the

268

K. E. W IJKillT^ — ()1?SIDIAN FROM ICELAND

volatile roiupoiients luiviiig been I'eleased during the initial cr'yslalli/.ation

of the spherulites. This is }3roved by several facts:

(d) The black obsidian glass can be seen at several points to have

flowed into a lithophysal cavity
whose walls had collapsed
slightly. The inflowing obsid-
ian Avas so stiff that it extended
as a tongue of glass into the cav-
ity (see center of figure 2 and
tigures 4 and o). These tongues
are of different shapes; the}' ex-
hil)it in cross-section the outline
of the cracks through which they
entered and are fluted longitu-
dinally with straight grooves
and lines which were impressed
on them by tlie irregular out-
line of the crack shown in figure
5. They resemble the product
obtained by the outflow, undei'
great compression, of a^v vis-

PiGURE i.^Radiai Lithui>hii-sa, in pari cous or plastic material, as iron.

recrystaiiized butter, or checse, thr(vigli an

Lithophysal cavity has collapsed slightly and irregular orifice. The ,bsidian

IS pierced by tongue of black obsidian. Speci- ^ moiLiian

men 8S433. Magnification. 15 X. tongues on entering the cavities

l)rokc down and crushed the delicate
lithophysal crystals extending from the
Avails. This proves that the major pari
of the recrystallization within the lith-
ophyssc took ])lace at a relatively higli
temperature, while the obsidian wa.-
still capable of stiff, viscous flow.

(/;) The tridymite crystals have the
form of hexagonal plates. These plates
show file irregular birefracting areas
cliaracteristic of tridjauite. The tem-
perature of formation was accordingly
above the inversion temperature, 120° Kh;ri;i: r>.sii<nriii pnied Tonfmc nf
C. Whether or not it was above 870°, '!'";'" '^^'^"'y »'««« projectimj i„i.,

' Uthophjjsal Cavity

the inversion temperature of quartz- spccinmi ss4:i;:. xMaguiiicaiiou, -u x.

Sl'llERi:T.lTr<:S AND LITITOPTIYS.K

269

tridymite, can not be determined from the data available. The presence
of tridymite is not decisive evidence of a temperature of formation al)ove
870°, for Fenner^^ has shown that it may crystallize as a metastable
phase at relative low temperatures, especially in the presence of fluxes.

In sonae of the outer cavities a later ferruginous staining has been in-
troduced, ])ut this does not extend into the rock for anv distance, as is

FiGtjisE G. — Remarkable Lithophysw in Oisidian
Cube-shape oavity. Specimen 88431. Two-thirds natural size

evident from tbc fact tbat the cavities on a iVesldy I'ractiii-ed surrafc do
not show the slightest trace of such staining.

To recapitulate: Specimen 884.30 proves detinitcly tliat crystallization
of radial spherulites took place as a result of the action of gases at high
temperatures, at wliidi tiie obsidian was still soft and capable of flowing
into fa\iti<'s whicb bail been sheared or had collapsed to a slight extent.
'J'br L-\ idencr of tbc presence of volatile components at high temperatures

I' .\in. .lour. s.i. lii. vol. :;i;. r.u:;, pp. .•{;n-.s.s4.

270

F. E. WRIGHT OBSIDIAN FROM ICELAND

is as clear in the Icelandic material as in the Yellowstone Park occur-

rences.

Specimen 88431. — In this specimen we encounter lithophysa; of a
shape and aspect which are unique. They are so remarkable that at first
sight they do not appear to be spherulites. The cavities are in the shape
of a cube about 25 mm. on a side, the walls of the cube having the ap-
pearance indicated in figure 6 and in the photomicrographs, figures 7
and 8. The inner walls are not perfectly flat, but show strong diagonal
ribs passing from one corner of a cube face to the opposite corner, as
though each cube face had not been quite fully developed into a i)lnii('.

/ i

,p*>

i !

k :

1 ,

y ..

FniuUE 7. — Lower Wall of LiUioijIiyna on lefl aide of lUjure 0
Shows character of crystallization. Specimen 88431. Magnification, 4 X

but still has superimposed on it four negative triangular tetrahexahedral
faces; each four-sided pyramid thus formed points toward the center of
tlie cube and not away from the center, as in the case of natural crystal
l»ounded by tetrahexahedral faces. Between the strong diagonal ribs
iiollow depressions occur. From the apex of each four-sided pyramid
fibers radiate toward the sides of the cube, as shown in figure 6. In addi-
tion to these lines of growth, a second set of structural lines and ridges
and cracks is present, cutting the radiating lines at right angles and
emanating as encircling waves from the center (see figure 7).

On examining these cube faces still further, we find that any little
in-egularity on the one face is imaged in exactly the same relative posi-

SPHERULITES AND LITHOPHYS.^ 271

tion on the face immediately adjacent to it; thus in figure 6 we observe
in the lithophysa on the left a sharply pointed facet on the diagonal rib
in the lower left-hand corner of the vertical face; this facet appears on
the horizontal face in precisely the same relative position and is shown
faintly in the photograph. Much better examples of this phenomenon
can be seen in the lithophysfe on the right side of figure 6, but they are
not well reproduced in the photograph. The fact that any irregularity
on the one face finds its counterpart on the face adjacent to it and inter-
secting it at the edge of the cube proves that the faces were originally
togethei- and were grMdiially forced apart as crystallization proceeded.

.V",

FiGuui; S. — Enlarged central I'art uf Figure 7
Shows (loci'oase in sranularity away from center. Specimen S84.'^l. Magnification, 10 X

Such pushing apart of a spherulite by the gas emitted during crystalliza-
tion or ])y tbe pulling apart as a result of general hydrostatic tension is
not unusual and would ordinarily be j)assed over unnoticed.

In tbe present instance the remarkable synunetiy of the lithophysa'
attracts attentioii, ami the observer iinds it diilRcult to pictin'e the mech-
anism of such a jjrocess. When it is realized, however, that a cube can
be considered to consist oT a set of six four-sided pyramids (figure S>,
negative tetrahexahedrons mei'ting in the center at theif apices, the six
cube faces being theif hases), the geomeli'v of the |ii'ol)leiu becomes vlv.w.
\\\ then, having starle(| with a small s|ihei-nlite and liaviii^' caused ii in
fi-acture s\ ininei I'icall V as a I'esull of the iidei'iial gas [•I'essni-c idong the

272

F, E. WRIGHT OBSIDIAN FROM ICELAND

lines of the pyramids of the cube, we then aHow crystallization to proceed
continuously with concomitant evolution of volatile components, which
tend to force the rigid walls still farther apart, we oljtain the present
forms. Evidence that this has been the process of development is not
lacking.

( 1 ) The radius of curvature of the outer wall of the right side of the
lithophysa on the right in figure 6 is variable. It is least in the center
of the segment and becomes increasingly greater as the margin of the
segment is approached; near the margin the curve of the outei- wall
shows a flexure. The edges of the lithophysal cul)e are veiy thin ami
onlv a thin film of crystallized material has been foi-nied next to the

■l

■

^HF^

r^^^^^^^^B

^Vi

'»* 4

k--

FiULUK y. — Biuf/i uiniitatir Ueprvsentation
of Cube 'built vp of nix Pyramids

The apices of the pyi'amids must meet
at the center and their ijases are the sides
of the cube.

FiGURK 10. — ElUiJ-sdid-like litlmiiliijsul Cuc-
ity, ivith central Girdle of crystallized
Material

Specimen n,s4:;i. Xatural size

glass, thus indicating that crystallization was active only a relatively
short time at that point. The ratio of the thickness of the crv'stallized
shell at the center of a segment to that of the crystallized lilm at its
edge is of the order of magnitude of 50 to 1.

(2) On one side of specimen 88431 a cavity, 9 mm. in diameter, oc-
curs, out of which the crystallized material has fallen, except for a single
equatorial groove (see figure 10 ) . In this case it appears that the spheru-
lite was not broken into halves until it had grown to an appreciable size,
and that then it was forced apart along a single plane, thus elongating the
sphere into an ellipsoid-like figure with a central girdle.

(3) A difference in age between the center and the margin of the
exposed faces of the lithophysa is clearly indicated by tiie change in
granularity of the recrystallized material. Beginning at the center (fig-

SIMlKHll.lTKS AND LIT IIOPIIYS.E 21<J

iires 1 and 8), we iiiid tlie original radial splierulitic nialeiial covered
witli a crust of geode-like crystals measuring up to 0.2 mm. in diameter.
These crystals decrease in size as we pass from the center toward the
margin, where they are only a few hundredths of a millimeter in diameter.
The majority of these lithophysal crystals are tridymite; they form
clusters and rosettes similar in every respect to the tridymites of specimen
88432. The tridymite occurs in characteristic hexagonal plates, showing
weak, irregular hirefringence and low refractive index, n <_ 1.480. No
(luaitz or cristobalite was observed with certainty. Extending into the
liidvmite crystals and holding them together is a radial, weakly bire-
fracting mineral of much higlier refractive index. Tt is probably identi-
cal with the fibrous, feldspar-like mineral which occurs in larger indi-
\ idiials in the cavities of specimen 88432, described above.

Scattered through the mass of tridymite crystals are small (0.05 to 0.1
111 111. in diameter), sharply developed crystals of a honey yellow to yellow-
liiown mineral of the following optical properties: Refractive index a.
considerably higher than 1.T8, but noticeably less than 1.85T; y, slightly
greater than 1.85T. Optical character negative; birefringence strong:
crvstal system apparently orthorhombic. On a section practically iioniuil
to the obtuse bisectrix the angle between the crystal edges was found l)y
measurement to be about 100°. All of these properties agree witli those
of fayalite, which also occurs in similar association in the Yellowstoiie
Park litho-^hysae. The angle noted above is probably that l)etween (021)
and (021), which is 99° 06' for fayalite.

The relative abundance of the fayalite is remarkable when we recall
that the total iron oxide content in the rock is less than 3 per cent.
Similar relations were recorded by Iddings for the Yellowstone litho-
physse. The fayalite crystals decrease also in size from the center toward
the margin of the lithophysal cube faces. The presence of fayalite and
tridymite as the chief minerals formed indicates precipitation from a
physico-chemical system different from that of the noimal rhyolite
magnui : the system consisted largely, of course, of volatile coinponeiiis,
which at the high temperatures attacked the crystals which had crystal-
lized from the magma itself. 'I'hese components were first set free on
the crystallization of the spheriilites. which in turn, at lowei' tempeia-
tui'es. were attacked hy them, and changes were |ii-o<luee(l which resulted
in new crystal phases more stal)le under the new conditions than the
oiiginal crypto-crystalline sid)stances of the spherulito. 'I'liere is no evi-
dence that during this recrystallization there was migration of material
away from the cavity. The decrease in size of grain of the new crystals
from the center to the margin indicates again that the gases acted for a

274 F, E. WRIGHT OBSIDIAN FROM ICELAND

much longer period at the center than at the margin ; in short, the center
is mucii older than the margin, and the gases active during the alteration
were evidently those set free chiefly during the primary crystallization of
the spherulites.

The evidence presented thus far proves that during the crystallization
of the spherulites volatile components were active within the cavities;
also that at the temperatures, at which the lava was still sufficiently
molten to flow into very small cracks, the remarkable deformations de-
scribed above were produced. Now the chemical analysis of this obsidian
shows that it contains 0.13 CI, 0.07 SO3, and 0.27 HjO— all volatile gases
which would be set free, in part at least, on the crystallization of the
silicates. It is not probable that either sodalite or noselite would be
farmed in the presence of so much quartz, and these are practically the
only silicates containing NaCl or Na^SO^ which would be likely to be
formed. We have seen, furthermore, that the escape of volatile com-
ponents continued as crystallization proceeded and as the cavity was en-
larged. The question arises : Did the pressure of this escaping gas force
the cavity apart or was the main factor an external uniform tension de-
veloped on the shrinking of the magma ?

It is evident that where gas bubbles are formed in a magma the vapor
pressure of the gas has been sufficient to overcome the internal pressure
of the magma : also that simple vacua of regular bubble shape in a viscous
magma would be difficult to form. Field experience and laboratory prac-
tice have shown that, in such instances where the magma is inclosed
between frozen walls and shrinkage occurs on cooling, cracks (joints)
develop rather than bubbles disseminated evenly through the magma.
Reduction of hydrostatic pressure in the liquid favors the formation of
gas bubbles just as does the opening of a siphon bottle containing car-
bonated water. Bubbles may begin to form, moreover, when the liquid
becomes supersaturated with respect to the gas. Increase of uniform pres-
sure raises the saturation limit with respect to the dissolved gas; con-
versely, reduction of uniform j)ressure loM'ers the saturation limit and
favors the escape of the gas. Gravity, furthermore, is a factor which
would tend to close any vacuities disseminated through the magma. On
cooling, it would seem, then, that a magma inclosed in a solid shell would
tend to shrink away from the roof and to leave cracks rather than simple
bubbles. The formation of bubbles is facilitated if there be a point of
discontinuity in the liquid (differences in potential). Tins is given in
the case of gas in the magma reaching supersaturation near some nucleus,
such as a minute crystal or spherulite. It is less easy, if not impossible,
to explain the formation of a vacuum bubble in a moving viscous liquid.

SPHERULITES AND LITHOPHYS^ 275

Another fact which bears on the present problem is the increase in
solubility of gas in a liquid with falling temperature. The effect of this,
if pronounced, would be, in the case of a simple bubble, a reduction in
its size with lowering temperature. Opposing such reduction, however,
is the hydrostatic tension which develops in the central portion of the
magma on cooling and which tends to enlarge the bubbles. The ultimate
effect which these opposing forces may have had on the bubbles in Ice-
land obsidian is not known, but the fact that the cavity was lined with
crystallized material would tend to retard the magmatic resorption of
the gas, and thus tend to produce larger cavities than othei-wase.

To summarize the conclusion briefly: Gas escaping from the. magma
on crystallization was an active factor in the development of the lithu-
])liysie in the ol)sidian from Hrafntinnuhryggur. It caused rocrystaliiza-
tion and aided to a large extent in enlarging the cavity as crystallizatiun
proceeded. The amount of energy required to effect the observed re-
crystallization in the cavities need not have been great, because the energy
necessary for the solution of the spherulite crystals first formed was prob-
ably largely oft'set by the energy liberated during the crystallization of
the lithophysal minerals. The shrinkage of the viscous lava on cooling
tended, of course, to reduce the uniform hydrostatic pressure; but the
chief effect of such reduction on the size of the bubble cavities was to
increase the :ate of evolution of gas from the magma (reduction oL'
solubility of gas in magma under reduced pressure). Shrinkage of the
magma alone without evolution of the inclosed gas would tend to produce
t;racks (Jomts) bearing some relation to the inclosing walls. That the
magma contained abundant gas, however, is proved Ijoth hy the presence
(if piniiiceous layers and ])\ the recrystallizing action of the gas on the
walls of the cavity. The conclusion seems, therefore. \\;tir;uite(l that in
i]\v II laruiiiiiiuhryggnr obsidian, and probably in most obsidians, the
pressure of tlie gas set frae from the magma as a result of ciTstallizatiou
and also of r(>duction of hydrostatic ])rcssure induceil h\' llie shi'inkinu
of the ceiili'al [)()i'tions of Ihe inagma on C(.)oling has heen an inipoi-tant
faeloi- in llie develo])n)enL of the lithophysa-'. To ascrihe the total effect
to Ihe nnifonn |iull or tension developed hy shi'inkage of the cooling
magma is not an ailci|iiali' hypothesis to account for iln' din'ei'cnt facts
anil iclations uliich haxc hccii ohserxcil.

h!j;<'OM>M{y MIXFJlALfi A.\D ETVlliyd PHENOMENA PnODVCED fiV JTOT

aih'CULATING SOLUTWNii

AlLlioiigh not sti'ictly germane to the theme of this paper, it may he
of inlei'esl to desi-rihe Ihe cITects pi'otliiccd hv hoi solutions on the nioi'e

276 F. E. WRIGHT OBSIDIAN FKO.M ICELAND

porous and exposed portions of the obsidian. As noted above, Ijoth
livalite and ahmite were deposited from these solutions on the walls of
bubble cavities. In specimen 88434 the gas bubbles adjacent to the
spherulites are usually coated with minute water-clear crystals of a sub-
stance which is evidently a secondary mineral introduced liy circulating
solutions after the solidification of the obsidian; this mineral agrees in
its optical properties with alunite. The largest crystals measure less
than half a millimeter in diameter and are bounded by the basal pinacoid
and l)y rhombohedral faces, which are triangular in shape. Basal cleav-
age is distinct and gives rise to a distinct semipearly luster on the basal
]nnacoi(l. As a result of this cleavage, it is an easy matter to obtain
sections normal to the optical axis, on which then the uniaxial, optically
positive interference figure of a mineral of medium to fairly strong bire-
fringence is visible, lihombohedral cleavage is also present, l)ut is poorly
developed. The refractive indices were measured by the immersion
method: w about 1.575, e about 1.595: birefringence about 0.020. Plard-
ness apparently 3 to 4. Slightly soluble in hydrochloric acid, but To a
greater degree in sulphuric acid. In tlie HCl solution potassium w;is
round to be present; also sulphuric acid. On heating in a closed tu1)e.
the mineral decrepitates and emits a white cloud of sulphurous fumes.
Tliis material heated on charcoal before the blow-pipe gives, after mois-
tening with dilute co])alt nitrate solution, the characteristic l)lue color
test for aluminum. The density was found by immersion of a clear
crystal in Klein's solution to be 3.73. These properties agree with those
of alunite, and the determination as such may be considered reasonably
certain. The alunite appears to have been formed during the later stages
of precipitation of the hyalite. Compared with hyalite, it is present in
small amounts. The small geodes of alunite, when examined under high
powers,^- glisten and sparkle with the crystal faces of this mineral and
are exceedingly beautiful. The same mineral occurs in the more com-
pletely crystallized rhyolite of specimen 88434, which is likewise lianded
and full of gas-bubble pores.

It is of interest to inquire into the character and the temperature of
the solutions from which the hyalite and alunite were deposited. In this
connection one feature is of special interest : The obsidian fragments and
blocks which are associated witb tlie hvalite and alunite occurrences are

^ For the examination of extremely minute crystals in the hand specimen, the follow-
ing method has l:)een found satisfactory : Use a binocular magnifying glass (magnifica-
tion. 65 X ) and view object illuminated by a strong electric light, partly inclosed in a
brass holder mounted on a universal arm, which is attached to binocular stand and can
be moved in any direction, thus enabling the observer to illuminate at will any particu-
lar crystal from any desired direction.

SECONDARY MINKRALS AND I:T( HIXGS

277

still unaltered, but their surfaces are deeply etched, pits and narrow
grooves cutting into the surfaces 3 or 5 and even to 15 mm. (see figure 11.
specimen TT616, and figure 12, specimen 88435). These markings \ary
in shape and size from semicircular grooves, which have been well chai-
acterized as lunar crater forms by ({. P. ^Ferrill,^' to straight channels
not unlike the marks left bv an enufraver's tools. The distribution of the
various markings, both it-giihii' and ii'i-i-giilai'. follows no discerniblr oi'ilcr;
and the (piestion of the mode of foi'niation of such remarkable etch
phenomena is of interest esjiecially heeause of the siniilnritv (d' these

Fn;i Ki: 11. — Ijiciiril Snrftuc of (ihshlimi (llass, Diiihlaiil h- in ('Inn itrter
Specimen 77(510. Two-thirds natural size

markings to those which are found on the moldavites of Bohemia, which
have lieen described in great detail l)y F. E. Sness,^* who considers them
to he of e.Ktraterrestrial origin.

In the present case the origin of the etch (igiircs is clearly shown by
the records contained in the present suite of specimens. The following
facts have a direct bearing on the problem: (T ) The etching is evidently
the work of hot and iirobablv alkaline solutions. This is inferred from

13 I 'roc. r. S. National Miisciini. vol. t(i. r.Ml. |.. \Sn.

".Jahrlj. (1. K. K. <T€oIogiscben Ilcichsanstaii, vol. ">(». I'miii. pii. i'.»:;-;{82.

278

F. E. WRIGHT OBSIDIAN FROM ICELAND

the obvious connection between the deposition of hyalite (specimen
S8435) and the etch pits. In figure 12 a face of ol)sidian is shown from
which a crust of hyalite was broken off. The surface shows etched
grooves and markings like the lines on a turtle shell ; they Avere obviously
formed during the deposition of the hyalite. A careful study of the
entire specimen under a binocular microscope leads to the conclusion that
the solutions actually bored into the obsidian and continued to do so until
a protecting crust of liyalite Avas formed. The irregular distribution of
the etch channels seems to be, in part at least, the result of the irregular
precipitation of liyalite from an exceedingly mobile medium, probal)ly a

I'lauuE 12. — Etched Surface of a small Ohsiilhin Frii<j"teiU

The surface was protected in part by a coating of liyalite circulating solutions which
reached the obsidian along cracks in the hyalite mantle. Specimen 88435. Magniflca-
(ion, 10 X.

hot solution with admixed vapors; in short, from liot volcanic emniuitious
which escaped from the intruded but still hot magma mass, in view of
the high silica content of the obsidian, 75 per cent, it is ])robable that
the etching solutions were alkaline and not acid. A glass bottle of the
composition of obsidian should be an excellent retainer for even hot acid
solutions. It is significant that the greater part of the hyalite was de-
posited before the alunite. This may indicate a gradual change in -the
composition of the volcanic emanations by the increased concentration
of sulphuric acid.

(2) Experiments in etching both crystals and glasses have shown that
the nature of the etched surface produced is dependent on the kind of

SECONDARY MINERALS AND ETCHINGS 279

etching medium and on the chai-after of the surface etched. The etching
process is not unlike tlie aln-asive action of sand-laden winds on exposed
rock surfaces in deserts.^'"' The attacking acid solution etches in the
direction of least resistance and the material is carried away in solution.
The solution currents form whirls and eddies, and thus favor unequal
attack even on a perfectly homogeneous surface. Furthermore, any ir-
regularities in the surface or material are emphasized by the solutions.
An examination of the surface of the obsidian of the most uniform
specimen, 88428, shows the presence of fine point irregularities, in the
shape usually of minute triangular-shaped areas, as though at such points
the cohesion of the obsidian was different from that of the surrounding
points ; this difference finds expression in the character of the surface of
fracture obtained on the splitting off of the glass chips. Such points of
unique cohesion are probahly the minute bubble cavities which are scat-
tered through the glass and are visible in thin obsidian splinters undei'
llic microscope. These points and cavities offer favorable points of attack
for the etching solutions, which, as the dissolving action proceeds, con-
tinue to enlarge the cavities, and thus possibly to produce lunar ci-ater
forms on some of the specimens. Another explanation of these forms is
that they are etched enlargements of original half-moon fracture cracks,
])roduced by striking the glass fragment a sharp blow. The distinct
wavelike lines, both radial from and concentric to the point of impact
of a blow which fractures a piece of obsidian, are Jines which exert a
directive influence on the attacking solution, and thus give rise to certain
t\-pes of the remarkable etch forms which we observe. Still another kind
of crack requires mention, namely, the shrinkage rupture cracks, as shown
in specimen 88429, described above. Into these fissures the solutions
cnior and tend to enlarge them. In the case of strain in the gla.ss the
solutions probably etch most rapidly along the lines of maximum strain,
and this again tends toward irregularity of etching on the exposed
surface.

In addition to tliese factors inherent in the etched material, any foreign
substance, as a precipitate, attached to the surface serves as an obstruc-
tion to the acid streams of the solvent and forces them to flow along cer-
tain paths. Attention has been called above to the effect of precipitated
hyalite in this direction. Observation proves that the pitted character
of some of the slightly etched surfaces is not due to a spongy layer of
original bubble cavities which have been exposed by subsequent frac-
turing.

«V. Goldschmldt and F. E. Wright: Neues .Tahrb., Beilage Bd. xvii, 190."., pp. 355-
390; Beilage Bd. xvlli, 1904, pp. 335-376.

280 I'. K. WRHiirr UEhllDlAiS FKOM ICELAND

(3) The matter of internal strain noted above is significant for two
reasons: (a) its directive influence on tlie etching solutions, and (h) tlie
light which it throws on the former history of the fragment under exami-
nation. In the case of a large mass of obsidian, the internal strains set
up on very slow cooling are virtually compensated at the period of their
formation, so that the chilled product is a remarkably well annealed mass
of glass far superior in this respect to the best optical glass.

Strain birefringence in the large fragments of the obsidian (specimen
88438) is hardly detectable even in the largest splinters, which are suffi-
ciently transparent for observation. Around the radial spherulites (speci-
mens 88433 and 88433) no strain birefringence could be detected in the
adjacent glass in the thin section. This proves a very perfect state of
annealing. On the other hand, the small etched fragments of obsidian
in specimen 88435, which were found near the pond noted above and at
some distance from the main obsidian mass, are in a state of severe strain.
Small splinters of these fragments show gray interference colors and
uneven distribution of the regions of differential compression and ten-
sion. The strain in these fragments is apparently even greater than that
produced on heating a small splinter of the annealed obsidian in a Bun-
seu burner to a temperature of 1,000° or 1,200° ('. and then quenching it
in water. This proves clearly that the fragments are not simply frag-
ments of the annealed obsidian mass which have been broken off and
transported to their position and there etched, but that they were cooled
very rapidly from a high temperature to relatively low temperatures.
Tlie natural inference is that they are shattered ejectamenta of the ob-
sidian magma after the manner of the bombs of less siliceous map-mas,
or that they represent fragments of the outer chilled crust of the obsidian
magma. The distribution of the strain phenomena indicates the first
rather than tlic second inference. On tlie assumption that these frag-
ments represent bombs, the irregular rupture shrinkage cracks are readily
explained. A study of the types of volcanic bombs ejected by rhyolitic
magmas and of the distribution of strain in them would be of interest in
this connection. It is also important to note that on heating the obsidian
in the Bunsen burner the obsidian tends to evolve gas bubbles and thus
to become pumiceous. The tendency toward pumiceous development in
some of the etched specimens has been noted above.

THE MOLDAVITES

In view of the great similarity between the etched surfaces of obsidian
fragments at Hrafntinnuhryggur and those of the tektites, especially the
nioldavites of Bohemia, which have been considered to be of extraterres-

THE MOLDAVITES 281

trial origin, it is of interest to examine the strain phenomena in speci-
mens of moi(Ui\ites. Moldavites are fragments of a green-eolorcd glass
which occur in certain gravels in Bohemia, especially near Budweiser and
Treibitschj and are characterized by remarkable surface markings similar
to those described above. The distribution of the moldavites is not
unlike that of Indian arrow-heads in the Middle West. The moldavites
occur here and there, but never in any manner indicative of their origin.
They approximate in composition a rhyolite glass high in silica. Because
of their abnormal distribution and remarkable surface markings, Suess
concludes, following a suggestion of E. D. M. Verbeek/^ that they are
meteoritic in origin, derived possibly from the moon. H. S. Summers,^''
in a recent study of obsidianites, concludes that the chemical evidence
also indicates that they are of meteoritic rather than of volcanic origin.
G. P. Merrill/® on the other hand, presents evidence against the necessity
for considering the moldavites to be of extraterrestrial origin because of
their external surface markings. The present study tends to confirm
and to strengthen the objections advanced by Men-ill.

With a proper choice of solution and temperature, it should be rela-
tiveh^ easy on rapidly chilled specimens of glass of moldavite composi-
tion to reproduce the surface markings and thus to produce artificial
moldavites. This Professor Merrill has shoA^oi to be possible by simple
means, namely, by suspending fragments of obsidian or glass in hydro-
fluoric acid vapor. The mode of occurrence of the Hrafntinnuhryggur
fragments is a good example of the result of the process at work in nature
on a large scale.

Two instances may be cited to prove that etching phenomena of this
type can bo produced on other materials: (a) In the course of experi-
ments on the etching of cleavage fragments of calcite, the writer ob-
served etch pits and channels in process of formation on the under side
of the fragment immersed in a weak solution of hydrochloric acid in a
beaker.^" (h) On a specimen of stalactite from Luray, Virginia (U. S.
ISTational Museum specimen 88436), the surface is pitted and grooved
with shallow markings across the concentric layers not unlike some of the
markings on the moldavites.

Passing now. to the consideration of strain phenomena exhibited by
the moldavites. we may first direct our attention to the different effects
which result from the various physical conditions under which strain is

1" .Tahrboek van het Arijiiwrscii in hcilci-l.-iiidish Oosliiulir. \(.l. x.\. IS'.iT. p. I'.'l.". Am-
sterdam.

'■ Proc. Roy. Soc. Vicdnia. vol. ill. |,(. 2. 1!»on. p. 4li.S.
I*' Proc. U. S. National Museum, vol. 40. r.ill. p. 4S.-..
'" Neues THhrliucli. I'.oilaRo Rd. xviii. 10(14. p. .'',40.

XXr — Bi'i,L. (Jkul. Soc. Am., Vot.. 26, 1014

2S2 F. !■:. WKKiTTT OUSTDIAN IMto.M 1(']':LAM)

produced in cooling glass. These are wol1 known in the glass industry
and apply with equal force to the cooling of a silicate glass of nioldavitic
or rhyolitic composition, provided proper allowance ])e made for differ-
ences which arise because of high silica content. On the cooling of a
mass of glass heated to a high temperatui-e, tlie outer portions of the
mass in contact Avitli air cliill most rapidly and coiitract, Init on so doing-
meet with resistance from the hot interior mass. This slirinkage against
strong counter-resistance produces radial' compression in the marginal
shell, which, liecause of the raiiid cooling, quickly becomes so stiff that
appreciable movement is no longer possible ; the material thus sets under
a state of permanent radial compression. The central portion contracts,
in turn, on cooling and tends to draw away from the now rigid incasing
shell. Tensile stresses normal to the boundary surfaces are thus set up
and the material soon acquires a permanent set under tensile strain.
The net result of such rapid cooling is therefore an outer zone of radial
compression which decreases rapidly toward the center of the mass; it
becomes zero (neutral l)and or band of no strain) and passes finally into
a wide central region of tensile stresses.

It is ol)\io\is that the relative intensities of the strain thus set up and
ihe relati\'e widtli^ <d' tlic zones of coiiipi-e^sioii and of dilatation depend
on the composition and size of the glass mass, on the initial temperature
of heating, and on tlie rate and conditions of cooling. Experiments have
shown thai in oi-dinary glasses the temperatui'c region at which the vis-
cosity of the material becomes so great that differential strains rtiay per-
sist for a period of time is between 2oO° and 4.")0° C. Above 500° prac-
tically all differential stresses are relie\c(l Ity Ibiw of the material, while
at 250° the movement in the material is so sluggish that a very long
period of annealing is i'e(|nire(l to ]n'oduce an apjn'eciable relief of sti'css
differences. At a still jow-ei- tempei-atni'e the glass is so rigid that under
small loads it beluncs as an elastic sdlid and the I'orces of restitnlioii set
up as a result of th(^ strain suffice to restore tlie material to its initial con-
figuration on I'elease of the load ; in short, strictly speaking, the glass is
no lonux'r \ iscons. accoi-ding to the established definition of the term. At
ordinary temperatni'cs the glass is so rigid, or its viscosity so great, thai
a state of strain may persist in it for geologic ages, as tests on obsidians
have shown. It is evident, therefore, that the state of strain of a glass
fragment may well serve as an indicator of the conditions under which it
cooled.

The strain phenomena in glass are not apparent under ordinary con-
ditions of observation, Imt they can be rendered visible by simple optical
methods, Avhich in this respect function as does the developer on the pho-

Till'; MOLD.WITKS 28^-)

tu^urapliic plate. The optical effects resulting I' rum strain were first
studied in detail l)y Brewster in 1(SL4, at a time wlien only the simplest
of optical apparatus was available and but little was known of double
refraction. JN'otwitb standing tbis, Brewster deduced fi'om a series of in-
genious experijucnts many of tbr fundamental laws of the optical be-
liaxior of glass straiiird ritliei- mccbanically by ditt'erential pressure or
tension or as a result of non-uniform heating or cooling. Brewster found
that a plate of glass under load is bii'efrat'ting : tliat the optical effect
])rodiiced is sensibly ])roportional to the intensity of the strain; that a
plate of glass under differential compression beha^■es optically as a uni-
axial negati^•e crystal with its principal axis in the direction of the acting
load, while under differential tension it acts as an optically ])ositi\'e uni-
axial crystal ; that in a glass plate cooled quickly from a high temperature
a permanent strain is imparted which is at maximum intensity next to
the outer surfaces (zone of compression), and which, decreasing toward
the center, reaches a neutral band and passes then into a zone of tension
in the central part of the plate: that compression produces retardation,
while dilatation causes acceleration of the transmitted light waves.

Since Brewster's time improvements have been made in the methods
of observing and measuring strain birefringence, but these rt'finements
are not required in the present problem. To study the distribution of
strain in an irregular glass fragment, the only a])])aratus required is two
crossed nicols and a sensitive tint plate. This is easily obtained by re-
moving condenser, objectives, and eyepiece from the microscope and ob-
serving the fragment immersed in a liquid of the same refractive index.
l''or this ])iirpose a small crystallizing dish or breaker is Mell suited as a
container, and benzol, with refractive index approximately 1.50, as an
iinmci-sion liipiid. Tlie purpose of the refracti\'e litpiid is io o\"ei'conie
the annoving sui'facc i-ellections from the glass surface, whicli tend Io
distui'li and to mask the intei'i'erence phenomena resulting fi-oin sti'ain.

Relufiiing now to the moldavites, we have three possibilities to con-
sider :

( 1 ) The molda\ ites are etched fragments of a large mass of slowl\-
cooled obsidian. In this case, as we have seen above, little, if anv, sti'ain
is present. Between ei'ossed incols the fragment is practically isotroi)ic.

(2) The moldavites are volcanic ejectaraenta which weic oi-iginally
molten, but were chilled rapidly during contact with the air. In this
case they should show a considerable amount of sti'ain, with an outer
zone of compression, an intei'mediate zone of no strain, and a central
region under dilatational strain.

284 F. E. AVRIGHT OBSIDIAN FROM ICELAND

(3 ) The moldavites are raeteoritic in origin. Tn the case of meteorites
the conditions are nnique. Tlie meteor enters the earth's atmosphere as
a very cold liody. The frictional resistance of the atmosphere very
quickly raises the temperature of the exposed surface of the meteorite to
the melting region. Such melted portions are then brushed ofP, Avith the
result that only a thin crust of the molten matter is left on the meteorites
Avhen they reach the earth's surface. The period of flight through the
atmosphere is of such short duration that the center of the meteorite does
not become appreciably heated. According to Professor Merrill, to whom
the writer is indebted for a statement of the conditions which obtain
during the fall of a meteorite, the only recorded instance in which a
meteorite was touched immediately after it had reached the earth's sur-
face showed that the meteorite was "stone cold." The result of such con-
ditions of flight and local surficial heating is intense local strain analogous
to the strains set up on inserting a large piece of glass into a hot Bunsen
flame. The glass fragment commonly cracks into pieces, or small chips
spall oif analogous to exfoliation shells on rocks exposed to sudden
changes in temperature. The outer forms of stony meteorites indicate
that they have been subdivided in this manner.

The distribution of the strains set up under such conditions can be
readily obtained by inserting the edge of a cover glass or object glass into
a Bunsen burner. If care be taken to avoid fracturing, the edge of the
glass plate melts, while the center and opposite edge are still cold. Ex-
amination of the plate after cooling shows the presence of a very narrow
marginal band under intense compressional strain, which decreases in the
direction of the center and passes through a neutral line into a zone of
tensional strain, which soon reaches a maximum and then diminishes
gradually and practically disappears near the center. The glass plate
usually breaks asunder later near the line of maximal tensional strain.

Examination of moldavite specimens from Bohemia^" showed a distri-
bution of strain identical with that described above for conditions of
cooling postulated under case 2, namely, those of a highly heated or
molten mass of glass chilled rapidly. The small etched obsidian frag-
ments from Hrafntinnuhryggur (specimen 88435) exhibit the same dis-
tribution of strain. In the moldavite specimens the strain is distributed
in such a manner as to indicate that they are not fragments of a large
mass of annealed glass (obsidian or artificial glass) or single meteorites,
but rather fragments resembling in character the spatters or splashes of
molten obsidian described above. It should be noted, however, that the
meteoritic origin of the moldavites is not absolutely disproved, for it is

™ The writer is indebted to Professor Merrill for the loau of these specimens.

SUMMARY 285

conceivable that all of the outer zone of intense compression and part of
the inter zone of dilatation have been etched away, and only the central
core of the original fragment is left. It does, however, prove that the
present surface markings of the moldavites are not original surface
markings produced on the fragment during its flight through space.
This conclusion is in agreement with the inferences which have been
drawn by Professor Merrill from the etching phenomena.

It may be noted that in highly siliceous glasses the birefringence de-
veloped for a given load is less than that developed under similar condi-
tions in ordinary, less silieeous glasses, wliich have niueli higher euefh-
cients of expansion.

Summary

'IM

he oljsidian at H rafntinniilirvggur, near Myvatn, Iceland, is of special
interest to the geologist because of the un\isual op])ortnnity it offers for
the study of the effects resulting From the |)hysico-cheniical conditions of
cooling, in the present paper the formation especially of spherulitic,
lithophysal, and pumieeous structures is discussed: certain remarkable
surface markings resembling the pits and grooves on moldavites are also
described briefly. They were produced by the etching effect of hot vol-
canic emanations on fragments of obsidian glass.

The evidence given above indicates that in the formation of the litho-
i:>hysae gases were active. These volatile components, wliich were released
from the magma dining tlie crystallization of the radial spherulites, at-
tacked part of the material of the spherulites; new ciystal compounds, as
tridvmite and fayalite, were formed which bespeak conditions of forma-
tion different from those undei- which the original spherulites were crys-
tallized. The pressure of the liberated volatile components aided mate-
rially in the original formation and subsecpient enlargement of the litho-
phvsal cavities. The general hydrostatic tension (external pull) result-
ing from shrinkage of the central part of the cooling magma jirobably
aided in this development. l)ut the inclosed gas pressing against the walls
of the cavity was also an important factor.

Volatile components set free during the crystallization of a sjiherulite
may either escape along minute cracks and spaces in the sphei ulite to its
margin and there form a bubble in the viscous magma ot the viscosity
of the magma may be such that the internal gas pressure forces asunder
the spherulite. In the first case the presence of the gas bubble adjacent
to the spherulite hinders the further growth of the spherulite at that
point, with the result that the spherulites with adjacent bubble cavities

286 V. K. WKKiHT OliSIDIAN l-'Ho.M K'JOLAXD

are well develo])e(l. as in speeiinens <S,s4;i() and SS-t;]-^, desci il)c(| nhoxc.
In the second case il is important to nolc that the forriiiu- apart of the
cavity was a A-erv slow process. 'Hie iirst rujjtnre tool< place wlien the
spherulite was small: the rigid walls of the cubical or irregularly shaped
cavity thus formed were constantly forced apart, Init continued to g]•()^v
as crystallization advanced. The edges of the cube were thin and in eon-
tact with the magma, which. hoAve\er, was probably so thick and viscous
that less resistance Wfis oifered to the slow forcing apart of the walls of
the spherulite than to the formation of gas bubldes adjacent to the spher-
ulite. Exam23les of this phenomenon are sliown l)y specimen 88-1-31. It
is not possible to determine from the scant evidence at hand the se\eral
quantitative factors which are essential to the formation of the type of
lithophysal cavities of specimen 88431.

iM'idence is also presented which shows i-leaily that the d('e])lv etched
surfaces on irregular fragments of the obsidian are the residt of ett-hing
by hot circulating solutions from which large amounts of hyalite were
deposited. Minute crystals of alunite were also deposited during a later
stage of circulating solutions. The close resemblance of the surface-etch-
ing phenomena thus produced to the surfaces of moldavites and other
tcktites is emphasized ; also the mechanics of the etching process by whieh
such extraordinary forms are obtained. The distribution of strain within
the moldavites is considered briefly. The conclusion is reached that
neither the external form of the moldavites nor the distribution of strain
within them can he considered to be an indication of their oxtra terrestrial
origin, as has been stated by Suess. This conclusion is identical with
that recently advanced by ]\rerrill. and the above cxidcncc seivcs to.
strenu'then the position taken bv him.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Vol. 26. pp. 287-294 JUNE 30, 1915

POST-ORDOViriAN DEFORMATION IN THE SAINT
LAWRENCE VALLEY, NEW YORK ^

MY GEORGE II. CHADWR'K

{Presented before the Society Decenttier 31, UUJi)

CONTENTS

T'ase

I iitroductury L'S?

(ienerul stratigraphy of the area "JST

Form and character of the folds •_'!)()

Time and cau.se of the fohlini,' lllti

Introductory

That the Paleozoic rocks of tlie Saint Lawrence Valley are gently
uiidulatdTy is no new aiiiiouiicenu'nt. tlion^li it may be so regarded for
tlu' area iniincdiately under discussion, namely, the Cauton, New York,
topographic (juadraugle. These undulations were described on the C'aiui-
dian side of the river as early as 1863 by Logan,- and again more re-
cently by Cushing for tlie Watertown district^ on the New York side.
Tile present j)a|)er I'ccords tlieir extension into the Ogdensburg-Canton
(|iia(li'angles and discusses tlie evidence as to their origin and their rela-
tion to thi' beds of pre-(_'and)rian rocks beneath. The location of the
two ipiatlranglcs is indicated on the kcsy map, figure 1.

(IknI'M.'ai, S'ii;APi(;i;Ai'in- oi- thk Arka

Thouiih tbe connti'v is bea\ily ilri ft-niantled, yielding few exposures.
wlien tbe hitter ai'e |»lotte(l and connected up with regard to strike and
to to|>ogra|)liy there I'esults a pattern of outcrop sufficiently complicated
(and lil<ely to be found more so on remo\al of the drift) to denote the
presen(;e of two I'et ii-ulat in^' sets of folds liere as in tlie Thousand Islands

' Manuscript received liy ilu* Secretary of tlie Society May 6, lOlfi.

Witli permission of lln' Iiiiccloi- of the Now York Stat(> Mnseiiiii.

= Sir Willinm K. liOKaii : "(JcoloKy of Caniuia." p|i. '.M. !M, '.Ml. IN. lid. 117. etci'ii-ra

■' I'l-iif. II. I'. Cnsliiiii;: I'.iiii. ll.'i, .\. V. Slalc .\lusriim, |ip. I'd. li:;. l.'ir.-l. ■',(>.

( 2S7 I

288

G. II. CIIADWICK POST-ORDOVIC'IAA' DKKORMATION

region

Nearly circular domes, with quaquaversal dips, are marked fea-
tures of the good exposures along the Grass and Eaquette rivers, occa-
sioning several inliers, while bowl-shaped synclines containing outliers
also occur. Though the dips are all low, seldom over five degrees, they
reverse frequently or the strike veers rapidly in all the large outcrops.
The general resultant is the very zigzag trace for the formation bound-
aries, as shown on the accompanying map, figure 2.^

No such zigzags are sho^\ai on the geologic maps of the State, as may
be seen at once on comparison with the last State map of 1001. Their

Figure 1. — Map showing Location of Canton Quadrangle and Belts of Formalions
adjacent thereto (after Logan and Merrill)

recognition has become possible through the refinement of the strati-
graphic units in this region inaugurated by Gushing and Ulrich. In
place of the old divisions, "Potsdam" and "Calciferous," we must nuw
recognize the following formations in descending order :

* See Gushing, op. cit., p. 113.

" A word of explanation is in place here. The Ogdensburg quadrangle is being pre-
pared by Professor Gushing, wliose manuscript map has been liindly transmitted to the
writer ; but the generalized boundaries drawn in figure 2 had been previously woriced
out by the latter in a crude way. Since they form a part of the evidence material to
this paper, they are here used with apologies to Professor Cushing, \^■hose map shows
the same essential fact of the larger zigzags.

A similar explanation and apology is due to Dr. J. G. Martiu. who has mapped the
pre-Gambrian rocks for the Ganton sheet.

GENERAL STRATIGRAPHY OF THE AREA

289

Upper Beekiuiuitowu (Ogdensburg) dolomite.

Uuconformity.
Bucks Bridge (approximately Tribes Hill) mixed beds.

Unconformity.
Heuvelton ("Twenty-foot") white sandstone.
Theresa mixed beds (as restricted by Ulrich).
"Upper Potsdam" (Kee.seville?) white sandstone.
Typical Potsdam sandstones (mostly red).

Tlie name Heuveltou is introduced, with Professor Ciisliing's consent,
lor the heavy white sandstone, recognized independently by him and by
the writer,*^ which from its resistant nature has proved the most valuable
stratum on the Canton quadrangle for the solution of the stratigraphic
problems injected by the obscuring drift-cover. It is cluii-acterized by

i. O njt/es

guc £,

%^h^Ar

TBuck's Tiridje.
H&u vel -tot]
The r&sa
Whi-f-e. 'Pois<:/<nrn
PrecamLri a q

FioiiRE 2. — Folded Paleozoic Rorlcs on Ogdenshiirg and' Canton Quadrangles

Scolitkiis canadensis and by large gastropods suggestive of an Ordovician
age, but seems conformable to the Theresa; the exact age is still in doubt.
Tbe overlying beds, totaling some -"lO to '10 feet on the meridian of Can-
ton, are characterized by PaUeophycas heverleyensis and a lower Beek-
mantownian or Tribes Hill fauna; but as they differ lithologically from
the beds of that formation in tlio Mohawk Valley and exact equivalency is
not yt't ))ro\ed, the temporary ilesignation Bucks Bridge is here retained.
'V\\v (listi'ibution of these rocks on the Canton map is shown in figure 3.
In total absence of exposures it has been impossible to carry the Pots-
(l;ini sandstones ('()iitinuously across the sheet in figure 3, though present
in various outliers. Tbe upper layers may extend thinly across beneath

tbe drift, as contciK

Professor Cnshint;'. but tliere .seems liardlv

" Uc|ii)rt ol' 1 liicctiji- (>r N. V. State Museum t'(jr lltl.'!. |)i). (11, t)4.

'I'.H) c. II. ciiADwicK — i'()s'r-()i;i)()\i(iAN 1)j:f()Umatj()X

r(M)iii for tliL'm uii the Eaquette River between the known Theresa and
pre-Cambrian outcrops at Potsdam village.' and the formation presuma-
bly cuts out somewhere in the interval to reappear just east of Potsdam.
There can he no question of the interruption of the lower or typical red
sandstone^ since the white beds are seen to rest directly on the crystal-
lines in the more northerly outliers.

FOBM AND CliARACTEU OF TIIJ-: FuLDS

Scrutiny of the map (figure o) reveals an interesting relation betAveen
the folds there indicated and the belts of ])re-Cambrian rocks that are
seen disappearing beneath them. From the way in which the Paleozoics
here lap around the crystallines, the area is favorably located to exhibit
this relation, which became apparent to the writer while yet ignorant of
Logan's and unmindful of Cushing's contributions. Here, as in their
areas, the alinement of the major axes is northeast-southwest parallel
witli the valley. But instead of the secondary set being gridironed over
these at right angles in the fulcral direction of the Frontenac axis, the
minor distortions in this region are dominated Ijy the diagonal course of
the underlying pre-Cambrian belts. With less drift-mantle this would
likely become even more apparent.

The question at once intrudes as to whether these very gentle undula-
tions are not initial dips of strata laid down on the uneven surface of the
much eroded crystallines or induced merely by \ertieal compression dur-
ing consolidation. But the proofs of actual deformation are also to be
i'omid. Figure 4 shows crumpling of the limestone layers in the old
quarry at Yaleville, on the west bank of the Raquette, a mile below Xor-
wood. Figure 5 is a remarkable inverted buckle (syncline) in these
same Bwkmantown dolomites two miles farther down the river at Nor-
folk; this crosses the stream, the water of which is seen reaching up into
its trough. Neither of these are conclusi\e, since similar structures are
often ascribed to glacial or other agencies, though nothing quite like the
latter instance has come to the writer's notice hitherto. But in the Pots-
dam outliers, in the southern half of the quadrangle, more convincing
phenomena are at hand. A notable chain of these outliers has been pre-
served from erosion in the Grrenville marble belt of Harrison Creek and
Grass Eiver (see figure 3). These occupy the middle of a pre-Potsdam
Valley, on either side of which the harder granite gneisses rise from -K)
to 100 feet above these Potsdam remnants. .\11 of these patches exhibit

"The type locality iov the Potsdam i ivd i is luiir miles farther up the Raquette iu a
pre-Cambrian embayment.

'(iiri'K'.X ()!•' (AN'l'ON ()rAI)i;A.\(iLK

291

A/or>i/'oIlu^

•i

»J

'((

(i.

rjnan^a"

ra/is

l-'li;n;i: ■".. I'lirliiil umlniiir Mai, i,f lUirtnii (^ttinlnmiilc . xhniiinii lU'Uitiun of I'dk'oxaic

h'liil.s III jii e-Ciiiiihritiii lli'llx

292

G. li. CHADWICK POST-ORDOVIC'JAN DEl^^ORMATION

disturbance, the most noteworthy examples being at the east end of the
largest, as shown in the cross-section (figure 6), and the area just below
the name "Harrison Creek" of the map. of which a cross-section is given

Figure 4. — Cnimpliiifi af Itcrkniantoini Limrstone in nhl Qvarry ut YalcvUle

Figure 5. — Inverted Buckle crossing Raquette River helow Bridge at Norfolk

in ligure 7. The close plications of the latter seem explicable only in
terms of a lateral compression, involving necessarily the underlying crys-
tallines. A slight pinching of the pre-Cambrian syncline is all that is
required, as illustrated in the diagrams (figures 8 and 9).

VALLEY DEFORMATION

293

, ^~<'f^ ■

Figure 6. — Actual Crosfs-section of Potsdam Beds one Mile northwest of nrirk Chapel,

New York

C,HC /a

PRESENT STRUCTURE OF VALLEY.
Figure 7. — Cross-section of Potsdam Outlier on Harrison Creek. (Vertical X 3)

f/yc. yi

yALLE-Y BEFORE C O M Pf? ESS I ON.
^Figure 8. — Ideal Cross-section of same Valley before Deformation begaii

l/ALLEY AFTER COM PR ESSt ON
Figure 9. — Same Valley after Deformation; dotted Line shows Present erosional Profile

204 (;. II. (■iiADM'H'K — r()ST-()i;i»()\'i(!.\N di-J'CIjm a'i kin

Tn the (liaoi-;nns (figures 7, 8. and 9) tlic AcrticMl scale is exagsierated
tliree times and the amoTint of compression is also oAcrdra'WTi for the
sake of ])ers[)ieuity, but dips as liigli as ;;o deiirees were measured licre
iu tlie Potsdam, and at least four u'ood sviidiiies can be nuide out in less
than a (piai'ter of a ndle, liaving always the steeper dips toward the south-
east as i\n tlie ervstallines. In figure li tliere is n(» exaggeration and the
di|)s are siiowii as actually meas;ired, reaeliing 4.i degrees at one point on
the east kiioll. The amplitude of tliese folds is (iuite the same (al)out
300 feet) as of those on Harrison Ch-eek, luit tlie jaAVS of the pre-Cam-
brian vise are not so \'isible here, the conditions being probably more as
in figure !'. At other near-by outcrops the Potsdam has suffered crush-
ing and mierofaulting or brecciation. and just north of Dekalb village
("Old Dekalb""), on the south margin of the Ogdensburg quadrangle, is
the fine examijle of crumpling figured long ago by Emmons.^

Time and Cause of thi-: FoLUJXd

These observations, which can be duplicatt'd at many other points in
the Saint Lawrence Valley, indicate that we ai'e dealing here with a true
deformation superimposed on the original stratification and invoking
rocks as young at least as the Beekmantowii. Ciishing" believes that these
movements were under Avay even earlier, and in favor of this view the
Avriter would urge the much greater disturbance of the Potsdam, and
particularly the red Potsdam, in the Canton region, the difference being
so marke(l as to lead to a search for an unconformity at the summit of
the latter — a search that failed l)ecause no contact could be located. The
most suggesti\(> locality is tlie knoll JTist south of old Dekall). on the
( Joii\-erneui- (|uadrangle.

In easting about for an exjilanat ion of this deformat i<in. which is wide-
spread o\('i- the district between the Adii'ondacks and the Ivaurentide
hills, beyonil the Ottawa Eiver (see key ma|) ) . if is most natural to tui'n
to the former as the seat of disturbance, since they have been repeatedly
domed upward, besides block-faulted. The comparatively thin veneer of
Paleozoics in the continually deepening trough (d' the Saint Lawrence
could hardly fail to experience some crowding during such domings of
the Adirondack massif, and all the facts seem to accord well with this
inference.

Dr. E. Emmon.s : Geol()j;.v of the Socoiicl Disiricl. .New Yoik. p. 104.
Op. dt., p. 114.

BULLETIN

OF THE

Geological Society of America

Volume 26 Number 3
SEPTEMBER, 1915

JOSEPH STANLEY. BROWN. EDITOR

PUBLISHED BY THE SOCIETY
MARCH, JUNE, SEPTEMBER, AND DECEMBER

CONTENTS

Pages

Close of Jurassic and Opening of Cretaceous Time In North Amer-
ica. By Henry Fairfield Osborn --- 295-302

Reasons for Regarding the Morrison an Introductory Cretaceous

Formation. By Willis T. Lee 303-314

Origin and Distribution of the Morrison Formation. By Charles C.

Mook 315-322

Sauropoda and Stegosauria of the Morrison of North America Com-
pared with Those of Europe and Eastern Africa. By Richard
Swann Lull 323-334

Paleobotanic Evidence of the Age of the Morrison Formation. By

Edward Wilber Berry 335-342

Invertebrate Fauna of the Morrison Formation. By T. W. Stanton. 343-348

Studies of the Morphology and Histology of the Trepostomata or

Monticuliporoids. By E. R. Cumings and J. J. Galloway - - 349-374

Present Condition of the Volcanoes of Southern Italy. By H. S.

Washington and Arthur L. Day 375-388

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Subscription, $10 per year; with discount of 25 per cent to institutions and
libraries and to individuals residing elsewhere than in North America, Postage
to foreign countries in the postal union, forty (40) cents extra.

Communications should be addressed to The Geological Society of America,
care of 420 11th Street N. W., Washington, D. C, or 77th Street and Central
Park, West, New York City.

Entered as second-class matter in the Post-OflSce at Washington, D. C,
under the Act of Congress of July 16, 1894

PRESS OF JUDD & DETWEILER, INC., WASHINGTON, D. C.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Vol. 26, pp. 295-302 AUGUST 17, 1915

PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

CLOSE OF JUEASSIC AND OPENING OF CPtETACEOTJS TIMK

IN NORTH AMERICA '

BY HENRY FAIRFIELD OSBORN

(Presented before the Faleontological Society December 30, 1914)

CONTENTS

Page
First symposium 295

Subject of second symposium 295

European Jurassic — Cretaceous division line 296

Diastl'opliic and paleontologic evidence as basis for determinations 296

Fauna and flora 298

Resume of conclusions of paleontologists, geologists, and paleobotanists. . 299

Character of paleontologic evidence ; 300

Ptiases of problem, to whom assigned 301

Summary 302

First Symposium

A year ago the Paleontological and the Geological Societies united iu
a symposium on T]i}e Close of Cretaceous and Opening of Eocene Time
in North America. That symposium brought out very clearly the ^ide
differences of opinion and practice now prevailing among American
geologists and paleontologists as to the kinds of evidence on which we
must chiefly rely in geologic and paleontologic correlation, chiefly as to
the relative criteria of earth movements and of paleontology.

Subject of Second Symposium

We are now met to discuss the characteristic features of another im-
portant period of geologic time, namely, the Jurassic-Cretaceous limits,
as they have been defined in Euroi^o. from Avliich, it can not be too

1 This paper, which was delivered oiiilly aud has since been put in the present written
form, is an introduction lo tho symposium on this subject held at the Philadelphia
meetings of the two societies December 29-31, 1914. It is the second paleontological
.symposium presented l)oforc the two societies in joint session. Manuscript received by
tlie Secretary of the Oeologicai Society .Tuly 2, 1915.

XXII— Bull. Geol. Soc, Am., Vol. 26, 1914 (295)

296 H. F. OSBORN— JURASSIC-CRETACEOUS TIME

strongly stated, we must take all our geologic time standards and de-
markations. In this connection I would like to repeat the main state-
ment in my address last year : "American events can be dated only by
comparison of American with European faunas and floras, unless simul-
taneous and world-wide diastrophic movements can be demonstrated to
have occurred." This statement does not refer to the general diastrophic
theory, which we are not now discussing, but to the attempt through
appeal to the diastrophic theory to determine such boundaries as the
Cretaceous-P^ocene and Jurassic-Cretaceous by reference to breaks in sedi-
mentation which may be local rather than world-wide.

European Jurassic — Cretaceous Division Line

In Europe the Jurassic-Cretaceous division line is by most geologists
drawn between the fresh-water series of clays and sands in England
known as the Wealdeu, and the imderlying Purbeckian ; in other words,
the demarkation may be expressed as follows:

Base of the Cretaceous = AVealden

Summit of the Jurassic = Portlandian-Purbeckian

The problem before us in this symposium is, how can this Old World
stage of geologic time be most surely synchronized in the New AVorld?

Having devoted many years to the special subject of correlation be-
tween the Tertiaries of Europe, IS^rtb America, and soutlieastern Asia,
I have formed tlie very strong personal o})ini()n that in correlation be-
tween such periods and stages as these we must rely chiefly on paleon-
tology. This is for the very important underlying reason that the most
stable, orderly, measurable, and coincident phenomena are those deep-
seated changes arising from the hereditary germ plasm which are out-
wardly and visibly expressed in the various forms of animal and plant
life. Paradoxical as it may sound, hereditary protoplasm is much more
stable than the surface of the earth.

Diastrophic Axn paleontologic Evidence as Basis for

Determinations

Eising and falling coast or sedimentation lines in the pre-Tertiary and
Tertiary, or even the larger earth movements causing true unconformi-
ties, such as the birth of mountain systems and the earth changes incident
thereto, may or may not be coincident in time in two continents on op-
posite sides of the world. As a matter of fact, we know that the suc-
cessive erogenic movements or birthdays of many great mountain ranges,

DIASTEOPHIC AND PALEONTOLOGTC EVIDENCE 297

like the Eockies, the Pyrenees, the Alps, the Himalayas, have not been
coincident in time. Similarly it remains to be shown that great coastal
movements, such as those of America and Europe in Tertiary time, were
coincident. Many are certainly known not to be coincident, and it fol-
lows that at least a very large percentage of disconformity and uncon-
formity is not diastrophic in the l)road sense in which the term is properly
used.

On the other hand, the progressive and retrogressive evolution of ani-
mal and plant types on the two continents, or even on the four continents,
presents a most impressive ai-ray of precisely or closely similar coinci-
dences of precisely or nearly similar events in time. If any great or
striking discords could be demonstrated between the rates of evolution of
animals and of plants of similar descent in different continental areas
then correlation through paleontology would largely break down; but
uniform rates of evolution of organisms of similar ancestry even where
widely separated geographically is the prevailing law, notwithstanding
that there are exceptional cases both of retardation and of acceleration.

It is absolutely necessary that those geologists who base their time de-
terminations on appeals to the diastrophic theory should establish their
first premise, namely, that the actual or alleged movements in America
were coincident in time with similar diastrophic movements in Europe
and Asia.

In the present Jurassic-Cretaceous problem it is necessary for the ad-
herents of the diastrophic system of correlation to prove that large and
coincident earth movements on both sides of the Atlantic marked the
boundary between Jurassic and Cretaceous time. First, that at the close
of the Jurassic a movement of elevation expelled the sea from the Eocky
Mountain region, and that following this in Lower Cretaceous time a
submergence took place. Second, that in England, where the close of the
Jurassic and beginning of the Cretaceous was first clearly defined by
paleontologists, a diastrophic movement took place during or immediately
after the Purbeckian, Third, that in other parts of the world there are
similar diastrophic boundaries between the Jurassic and Cretaceous.

To take but a single illustration : if we glance at the schematic section
of the relations of the Jurassic and Cretaceous in AYiltshire, England,
we find an entirely different set of conditions than those demanded by
the diastro])hists; not even the first condition is fulfilled, for the Jurassic,
with its closing successive stages — the Kim.eridgian, Portlandian, Pur-
hecl'ian — passes gently and without marked change into the Wealden.
There may be some disconformity; there is no angular unconformity.
Only after the time interval between the Jurassic and Cretaceous has

298

H. r. OSBORN JURASSIC-CRETACEOUS TIME

long elapsed, nameh', after the long Wealden stage, there occurs a great
earth movement, and the succeeding Cretaceous stages are deposited hori-
zontally on the shai"ply upturned basal Cretaceous, or Wealden.

This is clearly shown in the accompanying figure (figure 1), repro-
duced from Haug.^

FiCtRK 1

Cretaceous.

Upper
Jurassic

5.
4.

o
O.

S 6

—Relatiotix of the Jiirassir (1-H) nnd the Cretaceous (6-10) in Wiltxhire,
Evfilnnd. (After 11. P.. Woodward and K. Hang)

10. Turonian.
9. Cenomanian (= Base of Upper Cretaceous).
8. Albian.
7. Aptlan.

(Great diastrophic movement, causing angular unconformity.)
Wealdian. Iguanodonts more specialized than tliose of the Morrison.
Purbeckian. Mammals similar to those of the Morrison.
Portlandian.

Kimeridgian. Iguanodonts similar to those of the Morrison.
Lusitanian.

Oxfordian. Marine invertebrate life similar to that of the Sundance.
Sauropoda similar to the most primitive forms of the Morrison.
Toothless ichthyosaurs, OiJthalmosaiinis, similar to the Sundance
Baptanodon. Vertebrate and marine invertebrate fauna correlated
with that of the SiiiKhinrc, which is referred by Stanton (1909) to
the lower part of the Upper .Jurassic.
(Callovian.)

Faun'a and Fl01!A

Xow, let us examine more closely the European stages and their fauna.
In the classification of D'Orbigiiy the last stage of the Jurassic system
was designated under the name Portlandian, derived from Brongniart.
"This," observes Haug {op. cit., page 1075), "can be extended to the
upper Oolithic group by comprising within it the Purbeckian, wliicli is
simply a brackish facies of the superior portion of the Portlandian stage
and Avhich varies in thickness in different regions." Beneatli the Poit-
landian is the Kimeridgian, beneath the latter the Lusitanian , and be-
neath this again the Oxfordian. It is in tlie Oxfordian that the earliest
Sauropoda of the ty])e of Cetiosaurus occur in Europe, a type of dinosaur
which is in a stage of evolution similar to that of the Haplocaniliosaurus
of the Morrison of Caiion Citv, while within the Kimeridgian is found
a species of iguanodont dinosaur known as Caniptosaurus pvestividii,
which is very similar {teste Gilmore) to the Caniptosaurus nanus of the
Morrison: in fact, all the camptosaurs of the Morrison are more gen-
eralized and primiti\e in structure than the iguanodonts of the "Wealden.

- E. Haug : "Traite do Oeologie, vol. ii, Les Periodes geologiques."
Colin, Paris, 1908-1911, p. 1187.

8vo.

Armand

FAUNA AND FLORA 2l)U

Having brought the charge against the earth-movement tlieory that
no evidence has been adduced that at the close of Jnrassic time similar
great diastrophic movements took place in America and Europe, but
that, on the contrary, there is a striking discordance in the periods of.
•diastrophism, I now desire to bring the charge against the paleontologists
that those who have sought to solve this important and interesting ques-
tion of the age of the Morrison through paleontology have never done
their work thoroughly; most of the paleontologists, myself included,
have made hasty conclusions, based on incomplete examination and com-
parison of material which is very rich and certainly affords ample basis
for more exact correlation than has yet been made.^ From the Morrison
alone (the Jurassic or Lower Cretaceous age of which is in dispute) 151*
species of animals and plants have been named as follows :

Mammals, 25 Rhynchocepbaliau.s, 1

Birds, 1 Crocodiles, 3 (-}- 1 in Arundel of

Sauropodous dinosaurs, 31 (4- 8 in Maryland)
Arundel of Maryland) Turtles, 1

Carnivorous dinosaurs, 13 (+ 3 in Pterosaurs, 1
Arundel of Maryland) Fish, 3

Armored dinosaurs, 10-11 (-|- 1 in Species of invertebrates, 24 (+ 4 in
Arundel of Maryland! Arundel of Maryland)

Isuanodont dinosaurs, 11 (Campto- Species of plants, 23

saurs) (+ 1 ill Arundel of Mary-
land)

EeSUME of CONCLSIONS OF PALEONTOLOGISTS, GEOLOGISTS, AND

Paleobotanists

A vast literature has accumulated. In preparation for the geologic
section alone of my monograph on the Sauropoda for the United States
(Jeological Survey, my research assistant. Dr. Charles C. Mook, has listed
2;59 titles in the bibliography of the Morrison formation, the greater part
of which deal with the geologic structure of the formation itself in dif-
ferent regions. There arc, besides, a large number of papers on the
Morrison fauna, and Hora, for we have over 300 titles on the Sauropoda
alone. The conclusions which have been reached by the authors of these
various contributions and of the papers in the following symposium are
as follows :

' An exception to this statement may be made in favor of Prof. S. W. WilMston's ex-
cellent paper in the .Tournal of Geology for 1005 (vol. xili. May-.Tune, pp. 338-350). in
which he discusses the faunal relations of the Morrison.

••The actual number of species is probably less than this as many of (he si)ecles have
been founded mi fragmentary material and [irobably are synonyms.

300

H. F. OSBORN JURASSIC-CRETACEOUS TIME

Morrison of hoth Upper
Jurassic and Lower Cre-
taceous Age

J. B. Hatchei-, 1903, geol-
ogist and paleontologist.

S. W. Williston," 1905, ge-
ologist and paleontolo-
gist.

W. D. Matthew," geologist
and paleontologist.

W. B. Scott, 1907.

Chas. C. Mook, 1915, geol-
ogist.

T. W. Stanton, 1909, geol-
ogist and paleontologist.

T. W. Stanton, 1915.

Morrison chiefly of Coman-
chian or Lower Creta-
ceous Age

W. B. Scott, 1897, geol-
ogist and paleontologist.

S. F. Emmons, 1890, geol-
ogist.

Logan, 1900, geologist.

N. H. Darton, 1915, geol-
ogist.

W. T. Lee, 1915, geologist.

E. W. Berry, 1915, pale-
obotanist and geologist.

Morrison of Upper Jurassic
Age

C. A. White, 1883, inver-
tebrate paleontologist.

Edw. D. Cope, 1884, pale-
ontologist.

Henry F. Osborn, ISSS,
paleontologist.

Lester F. Ward, 1900, pale-
obotanist.

Wilbur Knight, 1900, geol-
ogist.

E. S. Riggs, 1901, paleon-
tologist.

O. C. Marsh, 1896, paleon-
tologist.

F. B. Loomis, 1901, pale-
ontologist.

C. W. Gilmore, 1909, pale-
ontologist.

W. J. Holland, 1912, pale-
ontologist.

H. E. Gregory, 1914, geol-
ogist.

Character of paleontologic Evidence

The fact that the evidence from paleontology has thus far not been
found conclusive is largely due, as stated above, to lack of thoroughness
in the comparison both of the carnivorous and of the large herljivorous
dinosaurs of the Morrison, which include forms resembling those which
range from the Oxfordian through the Kimeridgian into the Purbeckian
and even into the Wealden. In general, it is said the Morrison dinosaurs
are more specialized than those which have been found in the true British
Jurassic formations, but there are some very striking exceptions. The
mammals appear to be closely related in their stage of evolution with
those of the Purbeckian of England. This would tend to correlate at
least some parts of the Morrison witli the Purljeckian of England as
Upper Jurassic. This was the main strength of Professor Marsh's argu-
ment. The invertebrate fauna gives little satisfactory evidence as to
age. The Morrison flora is scanty, consisting almost entirely of cycads.
Lester F. AVard considered the cycads as proof of Jurassic age ; but some-

- W. B. Scott : "An Introduction to Geology." 8vo. Macmillans, 1907, pp. 680-681.
"It has been suggested by Professor Williston that different areas of the Morrison are
of different dates, just as we saw that the Millstone Grit (Upper Carboniferous) of the
Mississippi Valley is not a single uniform bed, but different beds of similar character,
formed successively and corresponding to several horizons in the great mass of the
Appalachian Pottsville. On this view, which is probably the solution of the problem,
the Morrison includes several distinct horizons, extending from the Upper Jurassic into
the Lower Cretaceous, but the discrimination of these horizons is yet to be made."

• Personal communication, 1915.

CHARACTER OF PALEONTOLOGIC EVIDENCE 301

what similar cycads liave been found in beds which are ahnost certainly
Gomanchian, so the cycads can not be used to finally determine this
(question. The relation of the age of the Morrison formation to that of
the Potomac beds of the East and of the Kootenie in the West is impor-
tant. The lower member of the eastern Potomac carries a flora which
is very similar to that of the Kootenie in Montana, and the Kootenie
flora, as pointed out by Berry, is closely related to the other well known
Comanchian floras. Geologically the stratigi'aphic relations certainly
appear to favor Lower Gretaceous, or Gomanchian, age for large portions
of tlie Morrison.

Phases of Problem, to v^^hom Assigned

1 have attempted by way of introduction to very clearly state the prob-
lem in regard to the age of the Morrison and the three answers which
have been given to this problem.

In the succeeding contributions to the symposium Mr. W. T. Lee, of
the United States Geological Survey, will apply the earth-movement
theory to the problem and treat the subject from the point of view of
the paleophysiographer.

Dr. Gharles G. Mook, of the American Museum of Natural History,
will point out the vast area of the Morrison formation, its variations in
thickness and in lithological character, with reference to its mode of
(ii-igin and the general sources of the material of which the formation is
fomposcd. He Avill show that the actual age of the individual exposures
of the Morrison formation in one locality may differ considerably from
the age of the formation in another locality.

Prof. E. S. Lull, of Yale University, will characterize the Sauropoda
and Stegosauria of the Morrison, pointing out their means of migration
and comparing the three great regions in which Sauropoda have been
discovered, namely, the Morrison of America, the Oxfordian to the
Wealden of western Europe, and the beds at Tendaguru in East Afj'ica.
Tiic African beds contain certain large and highly specialized dinosaui's
{Bracliiosaurus) similar to those in the Morrison; they are also reported
to be partly associated with or underlying Jurassic (Kimeridgian, Ox-
fordian) marine invertebrates.

Finally, Dr. T. W. Stanton, of the United States Geological Survey,
will treat the subject rather from tlie invertebrate paleontologic stand-
point ill a comparison of the Morrison and the Gomanchian in relation
to the overlying and nndcrlying formations in various parts ol' the west-

ern region.

302 H, P. OSBORN JURASSIC-CRETACEOUS TIME

SUMMAKY

When these contributions are published and can be carefully compared,
it will probably appear as the chief result of this symposium that the
intermediate theory is correct; that, as long ago suggested by Prof. S. W.
Williston, the Morrison sedimentation was a very comprehensive and
wide-spread process; that it began in certain localities earlier than in
others, namely, during Upper Jurassic times; that it extended well into
Lower Cretaceous times ; that all the sediments known as jMorrison rep-
resent a vast period of geologic time in which sedimentation was remark-
ably slow, because at no point does this so-called formation — which is
rather a stage or series of stages in the European sense — attain any con-
siderable thickness. The more primitive forms of Morrison life are
partly, at least, truly Jurassic, while the more specialized progressive
maybe are truly Lower Cretaceous.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA
Vol. 26, pp. 303-314 August 17, i915

PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

EEASONS FOE EEGAEDING THE MOEEISO^T AN" IJsiTEO-
DUCTOEY CEETACEOUS FOEMATION ^

BY WILLIS T. LEE

(Read hefore the Piil cimlolodlcdl Sociely Deremher SO, 107J/.)

CONTENTS

Page

Introduction 303

Faunal considerations 304

Physical considerations 305

In general 305

Principles 306

Equivalents and associates of the Morrison 307

Character of the Morrison 308

Structural relations 309

Physiographic conditions 310

Conclusions 313

References 313

Introduction

The position in the time scale of a non-marine formation like the
Morrison is difficult to determine unless it can be fixed in some way in
a succession of conformable deposits, some of which at least are marine.
Geologists have w^orked along the line of marine succession since the
origin of their science, and on this succession mainly the commonly ac-
cepted stratigraphic columns and time scales are based. However, after
all the excellent work of paleontologists, one of their nimiber informs us
that fossils alone too often lead to erroneous conclusions, and that "dias-
trophism affords the only means of finally attaining a reasonable, accu-
rate, and systematically constructed classification" (1, page 005)." If this

1 Coutrlbution to the symposium held at tlio Philadelphia meeting of the Society De-
cember .■'.0. 1014.

Published by permission of the Director of the U. S. Geological Survey.
Manuscript received by the Secretary of the Society April ?,. 1015.
a For references see list at end of paper, p. 31.3.

(303)

304 W. T. LEE MORRISON A CRETACEOUS FORMATION

be true fo]- marine formatioBS that have been most extensively studied,
how much more is it true for non-marine formations whose fossils are
often of questionable value in determining age ?

It is safe to say that periods of erosion, with which might well be
grouped periods of non-marine deposition, arc comparable in duration
to the recognized periods of marine deposition ; but relatively little atten-
tion has been given to them. It would seem tbat a study of ancient land
forms, together with a study of the physiographic conditions under which
they developed, might lead to the establishment of a time scale that would
be valuable for comparison with the scale now used, or at least serve as a
check on it. In this connection it is evident that fossil plants are worth
all tlie stud}- and consideration they are now receiving, for although they
are more difficult to collect than shells, they occur in non-marhie deposits
in number comparable to the shells in marine sediments. However, in
the absence of an adequate study of paleophysiography it might be well
to inquire if it is possible now to find and to apply physical criteria for
determining the age of a formation like the Morrison, whose place can
not be fixed in a marine conformable succession of deposits and whose
age is not definitely indicated by its fossils. I may perhaps be pardoned,
therefore, if, with due regard to the faunal evidence which I shall touch
on very briefly, I attempt to find criteria outside the realm of paleontology
that will aid in (Ictci'inining the age of the formation.

Faunal Considerations

It is well known to geologists that Marsh, who described so many of
the Morrison dinosaurs, maintained that they prove tlie Jurassic age of
the Morrison. The influence of his opinion is still strong, but geologists
have gradually l:)een drifting away from it. Marsh and others following
him have regarded the IMorrison as essentially equivalent to the Wealden
(2, page 591) ; but, although the latter is now generally regarded as
Lower Cretaceous, there are many who still hesitate to admit that the
Morrison is post-Jurassic in age. The Arundel or middle formation of
the Potomac group, as restricted by the Maryland Geological Survey,
contains dinosaur bones which, according to the recent studies by Lull
(3, page 178), correlate this formation with the Morrison. Berry (4,
pages 163-164) also has recently shown that the Potomac plants, which
occur mainly in tbe Patuxent formation below the dinosaur beds, are
closely allied to the plants that occur in the Kootenai, which is possibly
a little younger than ^lorrison (18, page 22).-

2 There is doubt as to the relation of the Morrison to the Kootenai, but Fisher (18,
page 22) has shown that the Kootenai lies with apparent conformity on beds which he

FAUNAL CONSIDERATIONS 305

There i.s one other consideration connected with the fauna that T wish
to submit before re\ie\\ing the physical evidence. It is well known that
the dinosaur fauna of the ]\Iorrison is so extensive and varied that it has
been regarded as the (■ulininating fauna of tlie age of reptiles (5, page
97). It is not strange tliat hind faunas, developed as they are in regions
of general lock destruction, appear in maximum development Avithout
the preliminarv stages where some exceptional condition makes })0ssible
their preservation. A fauna like that of the Morrison warrants the belief
in a long period immediately })receding, during which physical conditions
wer(! favorable for its development. If the j\Iorrison is Jurassic in age,
the time available for the extraordinary differentiation of reptilian types
seems insufficient and makes maximum development coincident witli min-
imum land expansion. If, however, the Morrison is Lower Cretaceous
and late Lower Cretaceous, as the physical evidence seems to indicate,
ample time for this differentiation is afforded by the long intersystemic
interval of maximum expansion of land areas which preceded its deposi-
tion. Furthermore, a natural consequence of such extensive and long-
enduring land conditions is a corresponding extensive prevalence of sur-
face erosion. Both the causal conditions of maximum land growth and
its consequent erosional effects constitute criteria of generally admitted
taxonomic value, the former being generally regarded as approximately
delimiting geologic periods, while the latter results in the major uncon-
formities which are properly used in separating geologic systems. That
the results of this erosion are not more obvious in some places is doubt-
less due to the fact that the lands of the Kocky Mountain region were
approaching the final stage of baseleveling.

Physical Considerations
in general

I'x'caiisc the |)ah'oii(()higic evidence will be presented by others, 1 shall
luive little to say of il aside from the above brief remarks and shall
approach Hie piohleiii fi-inii a physical standpoint, taking whai iiia\ he
ealleil ;i iilii/siiit/ni/iliic \ iew. 1 iiasimieh as many geologists maintain that
it is ini|ii-o))er to appioaeh a question of geologic age I'roni a physical
standj)oint, it seems advisable to make a brief statement of some of the
princi|)les on which my views are based.

recogrnizcd as the Morrison In Moiituiia. Hecause of tho close association and lithologlc
similarity of tlipso formations, thorc is a foelins on the part of some KeoloRlsts, among
them ('ami)l)ell and lierry, who have studied the question, that there is no essential
difference in age between them.

306 W. T. LEE MORRISON A CRETACEOUS FORMATION

PRINCIPLES

The position that I assume on this question is largely due to the prin-
ciples enunciated several 3^ears ago by Prof. T. C. Chamberlin in a series
of lectures that it was my privilege to attend. Some of these principles
have been more recently amplified in his article on "The Shelf Seas of
the Paleozoic and their Eelations to Diastrophism" (7), and I take this
occasion to express my aj^preciation of the service that Professor Cham-
berlin has rendered to the stratigrapher. Tt is sometimes difficult to
adjust the time scale of one region to fit a standard previously established
for another. It needs no argument to convince the reader that a scale
appropriate^for any one continent is imperfect and must eventually give
place to a universal standard^ and it begins to look as if the principles
of diastrophism may eventually take a leading part in the adoption of
such a standard, in the establishment of which the laws of terrestrial
ph3'sics will play an important part; for I believe, with Schuchert (21,
page 586), that "diastrophic action is at the basis of chronogenesis."

Without entering into a discussion of diastrophism, which, although
pertinent in this connection, is too large a subject to discuss here, I may
state that the basic principle that I shall use is this : A movement of land
or sea of sufficient magnitude to make an appropriate separation of sys-
tems on one continent must be recognizable on other continents and is
more likely to give exact time correlations than most groups of organisms.
In Europe, with which comparisons in this case are made, the Jurassic
closed with a retreat of the sea from the continent and the Lower Cre-
taceous was inaugurated by its return. It is not probable that the rela-
tions of land and sea would remain unchanged in America while such
movements were affecting the European continent. It seems altogether
probable that the withdrawal of the sea from Europe and from America
was due to some common cause and took place at the same time, and that
the ensuing early Cretaceous resubmergence began at the same time on
both continents. However, this postulate, sound as it may be, falls short
of complete solution of the Morrison problem, because the youngest marine
formation below the Morrison is of late Jurassic age, being correlated on
fossil evidence with the Oxfordian stage; and the oldest marine forma-
tion above it is of late Lower Cretaceous, of Washita age, leaving a possi-
bility that the Morrison might belong either in the Lower Cretaceous or
in the Jurassic.

It might be appropriate at this point to inquire Avhat constitutes a
geologic system. There are fundamental differences of opinion that find
expression in the various schemes of classification, but I think that most
geologists will agree that a system miglit properly be terminated by a

PHYSICAL CONSIDERATIONS 307

1 II ii.xi Ilium Avithdra^A•al of oceanic wateis from land ai'eas, and that tlic
succeeding system might proj^eiiy begin witli the initial return of these
waters.

During a retreat of the sea the emerging land is likel}- to he eroded,
and a non-marine deposit laid down during its return is likely to be un-
cniirormablo witli tlic underlying fornuilions and to he closely related
st.nici nrally 1o the overlying ('(U-nuitions. Wliili' this prijiciple is aj)-
plicahlr in oi'(lin;iry cases, tlic |)hysiogra|)liic conditions under which the
^rorrison wiis formed arc so cxtraordimiry that the possibility of an ex-
ception should he considered, [nasmuch as the Eocky Mountain region
was h)w in Morrison time, it seems possible that slight changes in the
ahitude of land relative to sealevel would change aggrading to degrading
streams, and vice versa. It is theoretically possible that a retreat of the
sea into which such streams discharged might have so lengthened their
courses as to reduce their gradients and cause them to deposit sediments.
There is, however, a limit to the possible thickness of deposits laid down
in this wa}^, and this limit seems to preclude the possibility that Morrison
deposition could be due alone to withdrawal of the sea. However, if the
unexpected did happen in this case and the Morrison was formed during
a time of retreat, it should be nlore closely related structurally and other-
wise to the underlying than to the overlying formations.

I f the diastrophic movement that caused the retreat of the Jurassic
sea l)e accepted as terminating the period, the Morrison must have been
formed either during a time of emerging land — or retreat of the sea —
in which case it is Jurassic, or during a time of subsidence of land — or
advance of the sea — in which case it is Cretaceous. Inasmuch as the sea
did not return to the Eocky Mountain region until the latter part of the
Lower Cretaceous- (Comanchean of Cham1)erlin and Salisbury), it re-
mains to inquire whether the ]\Iorrison is more closely related to the over-
lying Cretaceous or to the underlying Jurassic. For this inquiiy it is
necessaiT to consider a gi-ou[) of formations that are either equivalent in
age to the Morrison or are closely related to it.

equivalents; and AffSOCIATES OF THE MORRISON

In character the Aloni-on formation Ihrcuighoiit Wyoming and eastern
Colorado corresponds essentially lo llic hods at the type locality at Morri-

^ The reference of the Pm-gatoire formation, or I.owj^r rrctaceous, of the Rocky Moun-
tain region to the Wasliita epoch of the Lower rrotacoous Is in accordance with the
olasslflcation used liy the Geological Survey (:.'0). If. liowever, the Washita is Upper
• Tetaceous, as Berry asserts (-1, pages i:{0-1.37) and as Ilaug (Text-booit, pages 1100
iind 1293) and other European geologists l)elk've, the Purgatoire is also Upper Cretaceous
and the overlying Dakota sandstone therefore holds a position somewhat above the base
of this series.

308 W. T. LEE MORRISON A CRETACEOUS FORMATION

son, Colorado, and are desiguated lt> tlic same name. However, in west-
ern Colorado the Gunnison fonuiitioii. the upper part of which has been
generally correlated with the Morrison, consists of two memliors (8, page
.31), the upper of which is lithologically like the Morrison and contains
the same kinds of dinosaurs, while the lower one consists of eveidy bedded
sandstone and some fresh-water limestone. The upper, or dinosaur-bear-
ing, member is regarded as the direct equivalent of the typical Morrison
east of the mountains mikI of the Mcb^hno formation of areas farther to
the west and south. The lowci- nicmher has been considered equivalent
to the La Plata sandstone of sonthwestern (Colorado and to the White
Cliff sandstone of eastern l.'tah (19), which underlies marine Jurassic.
This may be correct, but it is not definitely known that the Cunnison
includes rocks of such diverse age, nor is it beyond question that the La
Plata and the White Cliff sandstones are time equivalents.

In northeastern New j\[exico the typical bone-bearing Morrison rests
on a massive sandstone, the Exeter (10, page 45), which is not present
in all places. No fossils have ever been found in this sandstone and little
progress has been made toward determining its age. When T first de-
scribed it, I suggested that it niiglit be as old as Triassic, l)ut was prob-
ably younger. Move recent investigations indicate that it is ])ossibly a
time equivalent of the La Plata sandstone. East of the mountains it
has not been found north of Xew Mexico, but extends westward to Las
Vegas (15, page 37), and occurs on the western slope of the mountains
south of Lamy. New Mexico (16, page CA\)). its extension farther to
the northwest, in a region where little is known of the geology, is prob-
lematical, and the La Phita sandstone of southwest Colorado has not been
traced eastward beyond Piedra Valley, in southern Colorado (!•, page
44) ; hence its correlation Avith the Exeter rests on lithology, structure,
and stratigraphic position.

CHARACTER OF THE MORRISON

The Morrison formation, including at least the upper part of the Gun-
nison, the McElmo, and other beds of equivalent age, extends from Mon-
tana to New Mexico and from the Black Hills and eastern New Mexico
westward to Utah, an area about 600 miles long and 300 miles wide. It
has been examined in lumdreds of ])laces and its character found to be
so constant and its thickness so regular tliat it must originally have ex-
tended with practical continuity over this great area. It consists gen-
erally of shale of various colors and tine-grained sandstone, with a small
amount of limestone ; but in some places, especially in western Colorado,
it contains some conglomerate. It is too well known to require extended

PHYSICAL CONSIDERATIONS 309

description here, and it is perliaps sufficient to state thai its character
and distribntion have been consideied sufficient to indicate that it was
probably deposited over floodplains on a nearly flat surface, in lagoons
and temporary lakes, and in marshes along sluggish streams. The phys-
ical peculiarities of the Morrison a it so striking and the fossils char-
acteristic of it have been found in so many places that there is little
difficulty in identifying it.

STRUCTURAL RELATIONS

] wish In call pai'ticular attciilioii to the stiiict iiral I'clations of the
^Morrison with the formations below and al)o\e it. At some of the locali-
ties vt^here the Morrison has been examined there is an abrupt lithologic
change from it to the rocks on ^\■hich it rests. This suggests a thne
break, although in most places there is no obvious discordance in dip;
Init the reality of the hiatus becomes apparent when we find the Morrison
overlapping older formations that range in age from Jurassic to Archean.

In most places the bedding planes of the Morrison aie so nearly parallel
with those of the formations above and l)elow it that the structural rela-
tions can only be appi'ehended by taking a broad view. In some ]>laces
in A\'yoming, northwestern Colorado, and I; tali the Morrison rests on
marine Jurassic, and in other places on older rocks. In western Colorado
the Gunnison is conspicuously unconformable on the older formations
(8, 9), the upper part, or direct equivalent of the Morrison, overlapping
the lower part, or possible efiuivaleiit of the La Plata sandstone. In
eastern Coloiado it rests on roeks of Triassic or Carboniferous age gen-
erally, but in some places, as near Pikes Peak (12) and east of the (rreen-
horn ^fountains (13), it overlaps onto the pre-Cambrian granite, lu
northern New Mexico it overlaps the I'^xeter and rests unconformably on
the Tiiassic. hi brief, the iclations of the Morrison to the underlying
rocks are \aried. and the niieniiroi mity below it denotes much more time
in some places than in otheis.

In strong coiitfast wilh (be uiiconrormable relations at its l)ase, the
Morrison is obviously conforinable w ith the lieds above it. In relatively
few places has the I'urgatoii'e, or ibe lower part of the so-called Dakota,
been proved to overlap the ^Fon^ison, and so many of the reported over--
laps have be(>n found erroneous (!•) that there seems to be no good rea.'^on
for postulating any considerable time break in the liocky ^lountain region
at the top of the Morrison, alilunigh some geologists have regai'ded such
a break as necessary in comparing the IJocky Mountains with other i-egions
(5, page 109).

310 AV. T. LEE MORRISON A CRETACEOUS FORMATION

The contrast between the Morrison and the overlying sandstone has
been pointed to 1)}' some geologists as evidence of a time break, and it
ndght be interpreted as such if it were not negatived b}- other evidence.
With few exceptions, the Morrison is present wherever the Dakota occurs
in the Eocky Mountain region, and these exceptions are found near the
areas over wliich the ^Forrison prolial)ly did not extend. Had any great
h:'ngth (if time intcrNciied lictwoon tlicsc roi'iiiiil imis, the soft IxmIs of tlie
Morrison would ]ii'ol);ilil\ have l)et'ii crodiMl ;i\\ay in some places; but jio
such place has yet been described. Be tbis as ii may, there is no escape
from the conclusion that the iMorrison, as a formation, is structurally
much more closely related to the overlying formations of Cretaceous age
than it is to underlying formations. This was recognized long ago by
Emmons (6, page 23), when he said: '^'From the point of view of the
stratigrapher, the assignment of the Morrison beds to the Lower Cre-
taceous rather than to the Upper Jurassic is much more desirable . . .
because it places the physical break whose effects are recognized over the
whole continent between these two great time divisions rather than in
the midst of one of them."

The same idea was recently expressed by Ulrich (1, page 615), when,
in considering a question somewhat similar to the ])resent one, he con-
cludes : "Let us then be reasonal)le and practical and accept with proper
valuation these diastrophic boundaries which nature has most clearly and
widely indicated.'^

PHYSIOGRAPHIC CONDITIONS

Some fifteen years ago, when I began a study of the Morrison forma-
tion, it was generally spoken of as a lake deposit. It was difficult to
conceive of a formation so wide-spread and so uniformly thin as having
been formed in a lake, and several lines of evidence indicated that the
formation is best explained as a series of fluviatile deposits. This hy-
pothesis seems to harmonize with all the facts that have been gathered.
It is evident to those who are familiar with the Morrison that the physio-
graphic conditions under which it was formed were very unusual. In
fact, it is doubtful if an area could be found at the present time that
would even illustrate them. It is cjuite impossible to adequately present
in a short paper the physiographic data affecting the Morrison problem,
but a brief review may be useful.

The great sandstone formations of Carboniferous age that surround the
Eocky Mountains and the presence in them of coarse conglomerate indi-
cate that extensive highlands existed there in Carboniferous time. The
Triassic formations also are conglomeratic in some places; but such

I'llYSlCAL CONSIDERATIONS 311

lii<;liUiii(ls as may have persisted there from the Carboniferous were being
eroded throughout the Triassic and Jurassic periods — a time amply suffi-
cient for the reduction to a condition of low relief of large land masses.
The time during which the Jurassic sea occupied the interior basin was
])robably only a small part of tlie period (14). The character of the
Sundance (Jurassic) formation indicates that this sea came in over a
well graded area. Later occurred what Emmons has called the Jurassic
movement, which expelled this sea from the continent (0, pages 31 and
23), and which, in his opinion, should mark the close of the Jurassic
period.

If the Jurassic movement produced any considerable highlands in the
Kocky Mountain region, they seem to have been reduced nearly to base-
level before Morrison time, for this formation bears evidence, as pre-
viously noted (5, page 119), of having been deposited on a nearly flat
surface. There were land areas in the Eocky Mountain region somewhat
above the level of Morrison deposition, for in some places the formation
abuts against their flanks (9, 12, and 13). In a few places conglomerate
is found in the Morrison (13 and 8, page 22), but on the whole the
lithologic character of this formation indicates the presence in the Rocky
Mountain region of lowlands rather than highlands. However, the dis-
tribution of the formation indicates that these lowlands were not exten-
sive. Cross and Larsen (11, page 238) recognize this condition when,
although they found the formation thinning out in some places, they
state: "It seems . . . not unlikely that the Morrison beds on the
east were connected originally with the Gunnison on the west."

The physiographic conditions of the time may be pictured as follows :
After the long period of degradation that brought the highlands of the
Eocky Mountain region to a condition of low relief, this region was up-
lifted sufficiently at least to expel the Jurassic sea. After a considerable
interval of time, indicated by the extensive overlap of the Morrison, this
region seems to have begun a slow general subsidence that resulted in
the partial sul)mergence of the interior of North America in the Lower
Cretaceous and the more complete submergence in the Upper Cretaceous
epoch. During this subsidence the streams deposited their silt farther
and farther inland as the gradients were reduced until the lands of the
Eocky Mountain region were finally submerged. The resulting fluviatile
accumulations — the Morrison — were in turn buried by the sediments
(Purgatoire formation) laid down in the encroaching Lower Cretaceous
sea, which submerged the Morrison formation in eastern New Mexico and
Colorado neai- llio close of Lower Cretaceous time. These Lower Cre-
taceous sediments are so closely associated with the Dakota sandstone
XXIII — Burx. Geol. Soc. Am., Vol. 20. 1914

312 W. T. LEE MORRISON A CRETACEOUS FORMATION

that until i-ccciitlv (17) thev were reganled us parts ol: the Dykuta. The
Purgatoire ami its i)()ssil)le time equivalents, Lakota and Fuson, and the
h)\ver part <ir the so-called Dakota, where a Lower Cretac-eoiis porticiii has
not 3'et been ifc(),i:iii/,c(h overhip the Tilorrisoii in only a few places (12).
Tlie Dakota appeals to liave entirely covci'ed the areas now occupied hy
the l.'ockv Moiiiitains. Althon,i:h it is now ai)scnt in nriny places because
of .subscipU'Ut erosion, ivinnants (d it occur on all sides of the luountains
;)nd in iiiteniionlane ai'eas at elevation^ ran.iiinu' to a nraxiniuni of i;'.Ji)i»
feet ahtive sealevel (v!\M. With very lew ext-eptions, the Morrison is
found below the Dakota (or Purgatoire. where that formation has been
identified). 'I'he uniform distribution of the^e sandstones, taken in con-
nection with their regularity in character and thickness, indicates that
the sands were spread out over a nearly level phiin. Although the Da-
kota in the KNicky Mountain ]egion is |)laiit-liearing and consequently a
so-called fresh-water fornuition, it is ])robal)ly a deposit of sand cleansed
bv wind and wave at the ailvancing fi'onl of the Cretaceous sea. It is
believed that the shai]» chan.ge from the .Moi'i-isou to the overlying sand-
stone is due to thi'^ change in the I'onditiou- n\' deposition rather than to
anv lapse of time between them.

The essential points in this pai't of the geologic histoiy of tlie Pocky
ilountain i-egion may he sumnuiii/.ed a> follow^: That i^art of the region
above seale\cl alieady degraded to a peneplain near the close of the
Jurassic period was disturbeil hy a movement that increased its relative
altitude and expelled the .Jurassic sea. The culmination of this move-
ment is regaided as the close of the Jurassic period. This uplift was
accompanied by continued degradation and followed by slow su])sidence,
which doubtless was inteimittent and oscillatory, but whicli finally re-
sulted in the formation of the liasin occu])ied by the interior sea of Upper
Cretaceous time. Th.e Moirison was deposited on this graded plain by
the streams made sluggish by reduced gradients. The region was partly
submerged in late Lower Cretaceous time by the shallow Avaters of the
sea, which reached at least as far inland as the present mountain front.
This partial submergence was followed, either immediately or after a
slight interval, l)y the greater sul)mergence of Tapper Cretaceous time, the
first sedimentary expression of which is the Dakota sandstone, which in
turn overlaps the marine Lower Cretaceous formations of the Pocky
Mountain region and extends over areas that were above sealevel in
Lower Cretaceous time.

CONCLUSIONS AND REFERENCES 313

('<)N(!H'SIONS

"^riK^ wciyiit (if ]iliysinur;)))liic ;iiiii other evidence liere c'oiisidered vseems
to wainiiit the iissiynmoiit of the JMorrison I'ormation hi I ho Lower Cre-
taceous or ( 'oiiiaiiche seiies for the following reasons:

1. lis |)hinl and \-ei'tehi'a(e fossils indicate close i-ehil ionship to the
Arunih'l and I'alii.xent iorniations of the I'otoniac and to tlie Wealden,
both of which are now general]}' regarded as Lower Cretaceous.

8. The evidence of a long period of erosion preceding the Morrison,
together with the culmination of the reptilian fauna during this land
stage, agrees best with the assignment of the Morrison to Lower Cre-
taceous.

3. It is much more closely allied structurally with overlying formations
of mid-Cretaceous age — late Lower Cretaceous and early Upper Cre-
taceous— than it is to the underlying formations.

4. The overlap of the Morrison on a variety of older formations is
indicative of a long interval of erosion.

5. The sea which occupied portions of the Eocky Mountain region in
late Jurassic time was expelled by a movement that is regarded as a part
of the diastrophism which brought the Jurassic period to a close.

. 6. The physical character of the ^Morrison and its relations to con-
tiguous formations indicate that it was deposited on a peneplain at a
time soon after the beginning of the Cretaceous subsidence, when the
surface was too near sealevel for further degradation, but not yet low
enough for marine sul)mergenee. It is therefore the first sedimentary
expression in tlie Eocky Mountain region of the new order of events that
culminated in the occupancy of the interior of Xorth America by sea-
waters in Cretaceous time. It is a non-marine forerunner of the Cre-
taceous niai'ine formations and thei-efore of Cretaceous age.

References

1. E. O. Ulricli : T\w Ordovician-Silurian honndary. Congre.s Geologuiue In-
ternational. XIIo session, Can.-idii, ]!)i;;, pages 59.3-667, 1914.

'2. T. W. Stanton : A comparative study of the Lower Cretaceous formations
and faunas of the United States. .Journal of Geology, volume v, 1897.

.'5. K. S. Lull: Tjic Keptilia of the Annidel formation. Maryland (^.eological
Survey. Lower Cretaceous. 1911.

4. Kdwai'd W. Hei-ry : Correlation of the Potomac formations. .Maryland

Geological Surve\. L.iwcr Cretaceous. 1911.

5. T. C. Cliamlierlin ;;nd R. 1). Salisbury: Text-book, volume iii, 1906.

(». S. F. Emmons: (Jeology of the Denver Basin in Colorado. U. S. Geological
Survey Monograph 27, 1896.

314 W. T. LEE MORRISON A CRETACEOUS FORMATION

7. T. C Chamberliu : The shelf -seas of the Paleozoic and their relations to
diastrophism and time divisions. Congres Geologique International,
Xlle session, Canada, 1913, pages 539-553, 1914.

S. W. T. Lee : Coal fields of Grand Mesa and the West Elk Mountains, Colo-
rado. U. S. Geological Survey Bulletin 510, 1912.

9. Whitman Cross and E. S. Larsen : Contributions to the stratigraphy of
southwestern Colorado. U. S. Geological Survey Professional Paper
90-E, 1914, page 44.

10. AV. T. Lee: Morrison shales of southern Colorado and northern New Mex-

ico. Journal of Geology, volume x, 1902.

11. Whitman Cro.ss and E. S. Larsen: The stratigraphic break below the Ju-

rassic sandstone in southwestern Colorado. Journal of the Washing-
ton Academy of Science, volume iv, 1914.

12. Whitman Cross: U. S. Geological Survey Geological Atlas, Pikes Peak

Folio (No. 7), 1894.

13. R. C. Hills: U. S. Geological Survey Geological Atlas, Walsenburg Folio

(No. 68), 1900.

14. T. W. Stanton : Succession and distribution of later Mesozoic invertebrate

faunas in North America. Journal of Geology, volume xvii, number 5,
1909, pages 410-423.

15. W. T. Lee : The Manzano group of the Rio Grande Valley, New Mexico.

U. S. Geological Survey Bulletin 389, 1909.

16. W. T. Lee: Stratigraphy of the coal fields of northern central New Mex-

ico. Bulletin of the Geological Society of America, volume 23. 1912.

17. T. W. Stanton : The Morrison formation and its relation with the Co-

manche series and the Dakota formation. Journal of Geology, vol-
ume xiii, 1905, pages 657-669.

18. C. A. Fisher: Geology of the Great Falls coal field, Montana. U. S. Geo-

logical Survey Bulletin 365, 1909.

19. C. T. Lupton : Geology and coal resources of Castle Valley, Utah. U. S.

Geological Survey Bulletin (in manuscript).

20. G. W. Stose: U. S. Geological Survey Geological Atlas, Apishapa Folio

(No. 186), 1912.

21. Charles Schuchert : The delineation of the geologic periods illustrated by

the paleogeography of North America. Congres Geologique Interna-
tional, Xlle session, Canada, 1913, pages 555-592, 1914.

22. W. T. Lee : Relation of the Cretaceous formations to the Rocky Mountains

in Colorado and New Mexico. U. S. Geological Survey Professional
Paper 95-C, pages 27-58, 1915.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Vol. 26, pp. 315-322 AUGUST 17, 1915

PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

OEIGIN AND DISTRIBUTION OF THE MORRFSON

FORMATION ^

BY CHARLES C. MOOK

(Read In'.forc lite Piileoniolo<jical Soeieli/ Dcct'.nthcr "0. lOJ'j)

CONTENTS

Page

Introduction 315

Distribution and thickness of the Morrison 316

Criteria for determining tlie origin of the formation 317

Conclusions 319

Introduction

The age of the Morrison formatiou is necessarily bound up with the
question of its origin and the physiograpliic conditions under which it
was deposited. The present paper is a study in this direction. The
writer was sent into the field in the summers of 1913 and 1914 by Prof.
H. F. Osborn to study the Morrison formation in connection with his
forthcoming monograph on the sauropod dinosaurs. Considerable time
has been spent in the winter of 1913-1914 and in the past fall in as-
sembling the results of this field study, together with a thorough study
of the literature of the subject. Some of the conclusions from these
studies are given in the present communication. The Morrison foi-ma-
tion is one of those series of beds which have been the subject of con-
siderable controversy. By the workers on the Hayden and other early
surveys they were known as "variegated beds/' Jurassic beds, Dakota
beds. Lower Dakota beds, Atlantosaurus beds, and in pai't Flaming Gorge
formation. Later they have been known locally as the Beulali shales,
Como beds, McP'lino Ix'ds. and (iinuiison formation. These local names

1 Contribution to tlio symposium held at the Philadelphia meeting of the Society De-
cember .".0, 1014.

Manuscript received by the Secretary of the Society April 3, 1915.

(315)

816 C. C. MOOK ORIGIN AND DISTRIBUTION OF THE MORRISON

are all given to parts of the same formation, and it is best to drop tliem,
in a general discussion, in favor of the name Morrison.

Distribution and Thickness of the Morrison'

Tlie Morrison, in tlie Ijroad sense, is widely distributed. At the type
locality in Colorado it is poorly exposed. It occurs in (lie hog-backs
along the eastern border of the Eocky Mountain front range, from the
Laramie Mountains south to the central parts of New ]\Texico : in the
Grand River Valley and tributaries in western Colorado and Ftali ; in
the canyons of streams tributary to the San .Tnan tvivor in southwestern
Colorado; south of the T'inta ^Fountains ami in the (Jrand Tfoo--1)ack in

Figure 1. — Diagramiaatic Rein c\tutuli(.n uf the TJiickncss of the Muni.soii Formation

in various Areas from Houth to North

A, maximum thickness in the Telluride quadrangle, Colorado ; B, thickness near Mack,
Colorado; C, thickness near Tensleep, M'yoraing: D, thickness near Belt Creek, Montana.
Scale, 400 feet to 1 inch.

western Colorado and eastern Utah; in a few isolated areas in Montana,
around the flanks of the Bighorn. Owl Creek, and A\'ind River ]\[ountains;
in local u])lifts and faulted blocks in eastern and central Wyoming, and
ai'ound most of the rim of the Black Hills.

In the southwestern areas the Morrison, or McElmo, has a considerable
thickness; near Green River, Utah, it is over 1,000 feet thick, accoi-ding
to lAipton ; in the Telluride quadrangle it is reported l)y Cross to be 900
feet thick; near Grand Junction and Mack, in the Grand River Valley,
it is about 700 feet thick; south of the Uinta Mountains it is about 650

THICKNESS OV THE MOERISON

P>17

feet thick; in the Owl Creek and Bighorn Mountains it is about 200 to
250 feet thick, and in central Montana it is less than KHi IWt thick.
From this it is seen to thin out toward the north. It is |)ossible, how-
ever, that the Kootenie may in part be equivalent to the Morrison. This
would reduce this northward thinning.

Eastward from the Telluride area, the formation is about 450 feet thick
in the Crested Butte quadrangle, 350 feet (possibly a little more) near
Canon City, and 200 feet or less in the canyons in eastern Colorado.
There is thus a decided thinning toward the east.

Toward the northeast, the formation is about 400 feet thick in the
khuaiupnicDi district, in southern Wyoming, 200 to 250 feet in the

PiGDRE 2. — DidiirtniiiiiiiHi- l,'ei>res(iitalioa nf the Thickness of the Morrison Formation

in rarioiis Areas from West to East

A. thickness near Mack, Colorado ; P., thickness at Garden Park, near Caiion City,
Colorado ; C, thickness at Red Rocks Canyon, in eastern Colorado. Scale, 400 feet to 1
inch.

\i(iiiity (if i^l\vllll^ and Coiuo IMutf, ami 100 feet or less around tlie
Hack Hills,
he noi'theast.

I')!ack Hills, '['here is also, ai-eordin^' to thi.s, a decided thinning toward

Ci;ni:i;iA Foi; i)i;ri:i;.M i xi \(i Tin-; OitiGix of tiik Formation'

'I'lie formation is made up essentially of rine-graincrl massive materials,
often lefeiTcd lo as "joint-clays,'" of sandstone, sliale, a very little
nieilinni-graiiied conglonieiatt', and some limestone in thin beds. Many
of the sandstones are ai'kosic. especially those near the base of the for-
mation. .Man\- of the sandstones and some (d' the sn-called cdays are e.x-
lrem(d\ calcareons, so thai it is dillieult to decide, in some cases, whether

318 C. C. MOOK ORIGIN AND DISTRIBUTION OF THE MORRISON

a certain specimen should be called calcareous shale or argillaceous lime-
stone. Many of the "joint-clays," when examined Avith the microscope,
are seen to be exceedingly fine-grained sandstones, sometimes with a
matrix of hematite, and not clay at all. True kaolinic clays do, however,
occur in some abundance. The colors of the formation vary to a great
degree, giving rise to the term variegated beds, often applied to the for-
mation. The clays are, in places, brick red or chocolate colored, due to
the presence of large amounts of hematite ; at other places they are gray,
white, purple, or nearly black. The sandstones are usually yellow or
white, but may be reddish. They are often made up largely of angular
or rounded quartz, as the case may be, witli replaced feldspars, calcite,
and minor amounts of volcanic matters and otlicr material. Tbe lime-

Figure 3. — Diug rum matte Representation of the Thickness of the Morrison Formation
in various Areas from Southwest to Northeast

A, maximum thickness in tlie Telliiride quadrangle, Colorado ; B, thickness in the
Encampment district, southern Wyoming; C, thickness at Como Bluff, Wyoming; D,
thickness near Devils Tower, Wyoming. Scale, 400 feet to 1 inch.

stones are usually thin, are often fine grained, and generally argiUaceous.

Perhaps the most characteristic features of the Morrison are the varie-
gated colors of most of the outcrops, the "uniformly variable" character
of the succession of beds, and the presence of distinct channeling, witli
sandstone lenses occupying depressions in the uiideilving clays.

The origin of the j\r()i-ris()n formation has been the subject of a number
of discussions in the past. Some workers have held that the beds weiv
deposited in tbe sea; others, such as C. A. White, have held that tbe
formation was deposited in a great lake. Kiggs has advanced the theory

CRITERIA FOR DETERMINING THE ORIGIN 319

that deposition took place in a number of small lakes, with deltas on the
borders, and possibly by rivers as well. Hatcher maintained that the
deposits were laid down in a series of tloodplains, with alternating deposi-
tion and erosion at successive levels.

In discussing this subject several considerations are of prime impor-
tance, other factors being accessory. The important facts to be considered
are these : 1, the formation was laid down on a comparatively level sur-
face; 2, the fauna is exclusively of the continental type, either land or
fresh water ; 3, the nature of the sediments is such as to imply deposition
in or by quiet water at times, and again in more agitated waters; 4, the
thickness of the formation is much greater in the west, and especially
the southwest, than in any of the other Morrison areas, gradually thin-
ning out toward the east and northeast; 5, internal structures, such as
channeling; 6, the "uniformly variable" character of the succession of
beds. Other factors to be considered are : the presence and kind of cross-
bedding, the condition of preservation of the fauna and flora, the varie-
gated colors, etc.

Conclusions

From these facts as starting-points we may infer that the Morrison
was deposited on a wide-spread plain of low relief, and probably of low
altitude. It is the result of alternating deposition and erosion, there
being no place, probably, where deposition went on continuously from
the time when the first beds were laid down until the uppermost beds
were deposited. The source of the material was to the west, and espe-
cially the southwest, of the present area of its outcrops.

These conditions may liave been satisfied by such, a history as the fol-
lowing: III .liirassic time there was a crustal disturbance and slight up-
heaval ill the present Rocky Mountain area. This disturbance is shown
ill tlie iiiuhilating character of the lied Beds noticed by Lee in northern
New iMexico. Following this upheaval, erosion progressed steadily until
much of the liocky Mountain area was reduced to a fairly level plain.
At the end of the interval, when the mountains to the west were fairly
well reduced in height and extent, the Rocky Mountain plain, if it may
be so called, was low and flat and the site of numerous lakes and swamps.
Erosion in the plain itself was no longer ])ossible to any considerable
exlcnl. Erosion al' the inoiiniaiiKnis areas to the west was sfill [jossilile,
however, mid went foruanl siradily. It is the ]ii(Mhicts of tiiis later
erosion wliicb imw coniprisc the Moiiisdii fdinial ion. A lew large
streams llnwing caslward or northeastward Iroiii (lie nld mountains.

320 C. C. MOOK ORIGIN AND DISTRIBUTION OF THE MORRISON

flowed across the swampy plains and deposited silt over broad floodplains.
Lakes were probably present and were the seat of deposition of many of
the fine-banded clays and sandstones. Deltas into these lakes, as sug-
gested by Eiggs, probably account for some of tbe coarser local sandstone
bodies. Some of the streams from the old mountains were much larger
than others and carried a greater load. From streams of varying size
and with different loads the deposits formed could not be uniform
throughout the whole area of deposition. Further than this, streams of
low gradient, such as those postulated, would deposit much of their ma-
terial before reaching a great distance from the original source. Ac-
cording to the evidence from the fauna and tlora, the depositional area
was not an arid one, certainly not through its entire extent. Eainfall
was probably fairly abundant, throughout much of the area at least, and
new systems of streams were produced on the plain itself. The basal
beds of formation were derived to a certain extent from the strata of the
formations underlying, as Avell as from the mountain areas. These
streams consequent upon the deposition plain would also carrv- a con-
siderable load, and in this way the formation would be built out from
itself. Material at the outer fringe of the area would therefore be much
younger than material deposited at the same distance above the base
nearer the source of supply. Shifting of channels would also result in
erosion of material already deposited. In this way a series of deposits
might be formed over a wide area, comparatively thin, with very great
lateral and vertical variation, and yet present the same kind of characters
over the whole area. Most of the formation being fine grained, the
streams were probably mostly sluggish. Occasional coarse iDeds, with
cross-bedding of the stream type, testify, however, to a considerable
amount of carrying power and a fairly swift current at times.

The whole area probably remained nearly level throughout tbe whole
depositional interval, though there were probably slight irregularities.
The difference in thickness between the beds at the southwest and those
at the northeast, providing the base rested on a level surface, is not
enough to contradict this statement. The southwestern areas, near the
sources of the material, proljalily were, at times, slightly higher than the
northern and eastern areas. The sediments in the southwestern areas
contain a larger proportion of coarse material and may have been built
up above the level of the larger part of the plain. Tt is also possible
that depression took place in the southwestern part of the area in the
later part of Morrison time, allowing fine silts to be deposited farther
southwest. Tt is noticeable that the fine clays in the southwestern area
are confined largely to the upper half or third of the formation.

KKT>A'ri()NS ()!•' 'IMIIO TAIt'l'S OK TUK M < M! 1! ISON

•.VI

322 C. C. MOOK ORIGIN AND DISTRIBUTION OP THE MORRISON

Such a history as outlined above will fit the conditions observed in
the Morrison formation, and it is probable that its history was something
of that nature.

It is important to observe that a given thichness of beds deposited
under the conditions of alternate deposition indicated would reciuire a
much longer time for its formation than beds deposited under conditions
of continuous deposition. It is perfectly in accordance with the above
outlined history for parts of the formation to be Upper Jurassic in age
and for other parts to be distinctly later than the Jurassic, perhaps well
up in the Comanchian. It could even be that practically ail the beds
represented in a single outcrop of the formation might be Jurassic, and
that in another area, not a great distance otf, be made up largely of beds
of Comanchian age. The accompanying diagram is an attempt to show,
in a veiy schematic way, the kind of cross-section the fonuation would
have immediately after deposition and before being covered or disturbed.

If the above interpretation be correct, great care must be taken in
judging the age of the formation as a whole, from a fauna or flora of
definite age, in any one locality or level. It will only be possible to de-
cide definitely the age of the various parts of the formation when ex-
tensive collections have been made from a number of levels in many
localities.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Vol. 26, pp. 323-334 AUGUST 17, 1915

PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

SATJEOPODA AND STEGOSAUEIA OF THE MORRISON OF

NORTH AMERICA COMPARED WITH THOSE OF

EUROPE AND EASTERN AFRICA ^

BY KICHARD SWANN LULL

{Read before the Paleontological Society December 30, 101 J^)

CONTENTS

Page

Introductory >, 323

Sauropoda . . . ., 324

Stegosauria 325

Migratory roads 326

Geographic and geologic distribution .326

Sauropoda 326

Stegosauria 327

Three vistas of dinosaurian societies .327

Tendaguru district of German East Africa 328

General description 328

Sauropoda .328

Predentata 329

Wealden .330

Sauropoda .3.30

Stegosauriji .332

Moi-rison ,332

Summary 333

Introductory

In discussing dinosaurs from a stratigraphic point of view, only those
groups are of value which are of a relatively high degree of specialization
and whose evolutionary stages are so sharply marked that a comparison
of those remotely removed geographically can be made with some degree
of accuracy. On this account the conservative carnivorous forms, whose
chief evolutionary change is increase of stature, are of little value. The

1 Contrilmtion to the symposium held at the Philadelphia meeting December 30. 1014.
Manuwciipt received by the Secretary of the Society April 'A, 1915.

(323)

824 R. S. LULL SAT ROPODA AND STEGOSAFRTA OF THE MORRISON

Saiiropod;!, oji tlic other liaml, and especially the armored dinosaurs,
which are highly specializetl ty|)('s, arc hori/on markers of importance.

Sauroi'()J)A

The Sauropod diiiosaiii's include some (d' the greatest of the worliTs
creatures, exceeded in size only hy the largest of existing whales. The
huge size, while in itself a high specialization, can only he attained l)y
members of a relatixely primitive stock. Thus we see in the attainment
of size the de\ elopment of remarkable specialization on' the part of skele-
tal detail, vet in the main plan of structure the Sauropoda were among
the most generalized of dinosaurs.

They were (piadiupedal reptiles, with a huge, relatively short body,
borne on massive, pillar-like limbs which still retained the archaic num-
ber of five digits in fore and hind foot, although the outermost ones were
in process of reduction. The neck and tail were of great length, while
the head, with its battery of prehensile teeth in the forward portion of
the mouth, was very small for so huge a beast, having a diameter less
than the average of the neck which bore it. The limb bones were exceed-
ingly heavy, long, and straight, with highly rugose ends, as though the
articulation betAveen them was in large measure cartilaginous. The ver-
tebral column, on the other hand, is a marvel of lightness, and from the
standpoint of strength, combined with rigid economy of material, is per-
haps the most remarkable piece of nature's engineering known. The
size, lightness of the vertebral column, especially of the neck, the com-
pressed and powerful tail, the incomplete articulations of the limbs, such
as are never found in terrestrial animals today, and the position of the
external nostrils on the top. of the head all point to an amiDhibious if
not an exclusively aquatic habitat. The weight of the limbs would serve
as ballast to permit the animal to wade in relatively deep water, while
the tail would be very effective for more active locomotion through the
water in case of need.

The feebleness of the dentition on the part of some genera at least has
given rise to considerable argument as to the food of these creatures.
All are pretty well agreed, however, that some luxuriant and nutritious
aquatic plants which could be loosened l)y the sharp claws or by the rake-
like teeth and then swallowed down in Jiuge quantities, without mastica-
tion, would best subserve the creatures' need.

The habitat of the Sauropoda may best be visualized by imagining
conditions such as now" exist in tropical America, more especially over
the coastal plain of the lower Amazon : low-lying lands, but little above

SAUROPODA 325

sealevcl, with sluggish bayous separated hy nuiiicrous islands clothed in
a dense tropical vegetation. h\ these iastnesses the creatures would he
enniparatively safe from their carnivorous enemies, while in tlie ipiiel
waters they would iijid support for their huge bodies both against the
burden imposed l)y gravity and the wai'nijig pangs of hunger.

Their structure of tooth, claw, and body ])oints conclusively to a ear-
ni\oi'ous ancesti'Y, and Ilueiie sees in the dinosaur I'hilcosdiiriis. fi'oni
I be (iei'iuan Keuper, a possible ancestral form. The change o\' habitat
may well ha\e been due to the growing burden of the llesh, which also
may have caused the dietary change. AMtliin some families of modern
reptiles, notably the Iguanida?, most of which are insectivorous, some are
also herbivorous and their range of habitat is equally broad, as they are
arboreal, terrestrial, burrowing, semi-aquatic, and one, Amhlyrhynclius,
is even semi-marine ! Hence the conjectured change of habit and habitat
on the part of the Sauropoda is not without modern parallel.

Stegosauria

The tStegosaurs are the armored dinosaurs Ijclonging to a dift'erent sub-'
order, all of which are characterized, with a single known exception, by
having the mouth toothless in front, but doubtless armed by a more or
less turtle-like prehensile beak. The dental battery, which reached a re-
markable degree of perfection in some of the latest types, is confined to
the rear pcn'tion of the jaws and is amply lltted tor the mastication of
herbaceous food. The Stegosaurs were quadrupedal, though, as DoUo
has shown, they doubtless descended from a bi|)edal ancestry, which the
increasing w^eight of armor caused to reassume the four-footed gait of
still more remote forebears. The armor takes the form of crocodile-like
scutes, which in certain portions of the body tended to form l)road pr.;-
tective shields through coalescence. In Stegosaurus, the aberrant genus
which has determined the name of the group, the median fore and aft
keel ot' the dorsal scutes has hypertrophied enormously, giving rise to the
huge upstanding jdates diagnostic of the genus. Other dermal elements
took the foriii of s|)ines, Ixinie by SI I'ljusdnrus en the distal end of the
tail, by other genera nwv dixci's poilions dj' the fi'anu', although I do not
know that the e\ idence for llieii' alleged |)o>ition is always clear.

Of the habits of 1 be Stegosaui's we know little: tlic teeth in known
types, iiotabK in S/rf/n.^aiiriis itself, ai'e i-elati\ely leeblc coiii|iai'ei| witii
those of the arniorless iy|ie and with those of the I'eratopsia : hence the
infei'ence is that their food must ha\e liceii of a nci'v succulent ciiaracter
ami of sullicieiit abundance to maintain the Itulk of a creature whose sub-
stance was two or three times that of an elephant.

826 R. S. LULL 8AUR0P0DA AND STEGOSAURIA OF THE MORRISON

The liribitat is also open to qiu'stioii, though, as I have sliowii. the
Saurojioda and Predentate dinosaurs seem to have oeeupied dilTerent
habitats — the one amphibious or aquatic, the other in the main terrestrial ;
fur in no other way can we account for the marked differences in distri-
bution of the two orders, which, reduced to a final anal3'sis, have gone so
far thnt the two groups are rarely found in the same quarry, even within
the same region and geological formation. This statement is, however,
in part refuted by Hennig, who remarks that at Tendaguru, German
East Africa, such limitation does not hold, as the occurrence of Sauro-
poda and Stegosaurs seems rather to be a uniform one throughout.

In the genus Stegosaurus, which is perhaps the best known and least
understood of armored dinosaurs, the evidence of imperfect limb articu-
lation, which was given as partial evidence for aquatic life on the part
of the Sauropoda, is also seen, though to a less txtent. There is in
Stegosaurus a powerful, laterally compressed tail, with long neural spines
above and chevron bones below, which would serve as a very efficient
swimming organ were the burden of armor plates and the rigidity of the
body not too great a handicap to semi-aquatic life.

Migratory Roads

Both groups of dinosaurs were great travelers. I myself ha\ c followed
their migrations over thousands of miles of the earth's broad surface.
W'itli the Sauropoda the route may have been along the continental mar-
gins from home to home, miu-h as in the case of the hippopotami today,
which, though denizens of the African streams, nevertheless swim boldly
out to sea from river mouth to river mouth and thus pass by the inhos-
pitable regions which would otherwise effectually bar their progress. In
this way the occurrence of Sauropod remains in marine or brackish water
sediments in Madagascar and East Africa may perhaps be partially ex-
plained. The Predentates as a whole, however, seem to have chosen- the
lar^d route, and their lines of migration will be less surely traced even
with the increase of our knowledge. This route distinction, however, may
account for the peculiar faunal likenesses and unlikenesses between Eu-
rope, America, and Africa, which have yet to be told.

Geographic and Geologic Disteibution

savroi'oda

Geographically the Sauropoda were a very wide-spread race, being
exceeded only by the carnivorous dinosaurs in the extent of their wander-

GEOGRAPHIC AND GEOLOGIC DISTRIBUTIOX 327

inffs, the ranse including western and eastern N"orth America, J*]ng1an(U
nortliern France and Portugal, East Africa and Madagascar, India and
far ]*atagonia. Geologically they appear suddenly in widely remote lo-
calities as though "living forms, limb'd and full grown, out of the ground
uprose," the earliest types l^eing in rocks of early Middle Jurassic
(Bath(mian) age. This sudden apparition, of course, implies a long, as
vet undiscovered, antecedent evolution. In ever im-reasing numbers
Siuir()|H)da a])pear with the passing of Jurassic time, until with the dawn-
ing of the Comanchian the full inflorescence of the race is attained, and
not long after, geologically speaking, the huge forms are l)lotted out ; for,
as Hatcher has shown, they were so absolutely dependent on one peculiar
type of habitat that, with their great size and consequent slow maturity
and rate of increase, very slight geologic changes would bring about their
extinction.

8TEG0SAURIA

The armored dinosaurs are confined almost without exception to the
northern hemisphere, but recent developments at Tendaguru, East Africa,
have brought to light immense numbers of "Stegosaurs," the estimated
number of bones in but two quarries being no less than 1,850 ! These
represent apparently two species of an undetermined genus, small and
highly spinescent ; but we are not yet made aware of their exact relation-
ship with others of the gToup. With this notable exception, the armored
dinosaurs are unknown from the southern land-masses. Geologically the
range is from the Lias to the close of Mesozoic time; Stegosaurus itself,
however, represents an aberrant, short-lived race of late Jurassic and
probably early Comanchian ( AFori'ison) age.

THREE VISTAH OF DINOSAURIAN SOCIETIES

During the Upper Jurassic and tlie (*omanchiau we are given three
vistas of dinosaurian societies in which the profusion of animals makes
fairly accurate anatomical conipai'ison in some instances possible. These
are the American Morrison of Wyoming, Colorado, South Dakota, and
Utah; the Tendagurn of German East Africa; and the late Jurassic, and
especially the W'ealden. of l-^igland and northern France. Of these the
greatest variety of Saiiio[)od genera and species are known from the
Morrison, including live families from which no fewer than in genera
and 23 species have heen described, ranging from more or less generalized
to highly specialized types. Of these families certain are exclusively
American, some have representatives in Europe, while others include the
dinosaurs of Tendaguru, there being, so far as my researches have taught
XXIV— Bull. Geol. Soc. Am., Vol. 26, 1014

328 R. S. LULL SAUROPODA AND STEGOSAURIA OF THE MORRISON

me, no apparent direct connection l)etween the allied English, French,
and rortuguese Saurojjoda. on the one hand, and the (ici'inan Eas^t
African forms on the otlier.

TENDAOVRU DIS'IHICI or (IHUM.W I:AST M'IUVA

(icncinl (Icscrijil Ion. — 'Flic dark ((Hit iiiciit srciii- drstiiKMl to fui'iiisli
the data which will ult iiiiatcly decide llie age of llie Saiii'o|i(i(|d)cariiig
beds of Norlh Ainei'ica and |t(issii>ly of lMir()|te. fni- here the dinosaur-
hearing strata aie inlerlxMlded willi marine zones rich in invcrtel)rates.
which will enable stratigraphers to li\ their age with a gi'eat degree of
aecui'acv. Professor Schuehert. in a review of Hennig's work. "Am
Tendaguru," - thus describes the region :

"The hill Tendaguru, less than 100 feet high, lies isolated on a high, thickly
wooded plateau averaging about 650 feet above the sea, and is the central
point from wiiieh all of the diggings have been (»])erated. It is in the midst of
an extensive dinosaur cemetery, for at oni' time there were twenty exhuma-
tions in operation scattere<l over ."10 sipiare kilometers, or across one degree of
latitude (between i)° and 10° south and 39° and 39° 30' east).

"In a thickness of about 500 feet exiioscd along the stream Mbenkuru are
found three distinct horizons of soft sliale with <linosanr remains, separated
from one another l)y hard eoarsc-gr.iiiied sandstones to conglomerates that
have an abundant marine invertebrate fauna. Each marine division has its
own assemblage of forms, and makes terraces along the river valley. . .
All of the beds are of one continuous series of deposits, as the different hori-
zons grade into one another. The conditions of deposition tlierefore appear to
have been an alternation of exceedingly shallow marginal seas that came to
be filled with detritus and changed into great mud flats flooded by rivers and
possildy in part by high tides. Three such cycles are recorded. Dinosaur
Ixaies do not occur in the marine deposits l)ut begin in the transition zones;
where they occur with Belemnite guai'ds, and may be so abundant as to make
bone conglomerates. Where the bones occur in greater abundance there ap-
pear to be no marine invertebrates.

•'In the lowest dinosaur zone there is but little good material, while the
highest one is not at all so rich in remains as is the middle division, out of
which most of the bones . . . have been taken."

Sauropoda. — The dinosaurian material, in so far as it has l)een made
known to ns, contains representatives of all three snhoi'ders of dinosaurs.
Of these the Sauropoda are re])resented hv three genera, each of which
includes two species, and there are in addition at least two other forms
as yet iindescribed (191-J). The Sauropoda thus far recorded are, first.
Gigantomurus Fi'aas. including the species afruaniis and rohnstw^.
These Fraas considers most nearly like the Morrison genus Diplodociis

^Amer. Jour. Sci. (4), vol. xxxv, 1913, p. 36.

GEOGRAPHIC AND GEOLOGIC DISTRIBUTION 329

I'l-oiu certain similar cliaractcr« m vertel)ra\ chevrons, and nWuT elements.
Of this genus Janensch says: "So far as can now l)e seen, the later in-
vestigations confirm FraasV view that (J. afncaiinx in its slriutuiv shows
distinct accord with the North American genus Di/i/nJnciis."

The second gi'oup of Sauropods is still more remarkalile. in that it is
so verv similar to a certain Morrison type as to he referred to the same
genus, /Innhiiisiiiii IIS. proposed Uy Uiggs in 1!)04. 'Die memhers of this
genus ai-e descril)e(| as of extremely massive l)uild. with lore limhs etpial-
ing or exceeding the hind liinhs in length, with an imineiise body — as
the !)-foot rihs imply — and with cervical vertebra' which may exceed a
meter in length. The total length of these animals, judging fi'om the
Tendaguru estimateSj could not have heen much less than 100 feet.-'
Bmrhiosaiinis altitkorax is the American species, wliile the African hn-ms
are known as B. hnnuai, with an extraordinarily long neck and a humerus
from -.MO to 'lAo meters in leng-th ; and B. fransi. which was smaller,
with an u])per arm hone measuring hnt 1.70 meters.

'I'lie third genus is l)icr(BOsauru.'< Janensch, having neck veriehi'ie of
modeiate length, with two high, completely separated spinous processes.
This pairing of the spines is continned hack over the dorsal region as
far as the rump. Bifurcated spines are not a unique feature. ;is I hey
are present in Bronfosaunis and Diplodocus, among other genera; hut,
nowhere, to my knowledge, are they carried to the extreme of s|)cciali/a-
tion seen here. The American genera in which these spines are paired
generally show more or less deep lateral depressions, pleiirocoeles, on
either side of the vertehral centra. l)ut these are lacking in the African
form. Two species of Picnrosdiinis have been described. IK Ikihsc-
iiiiiiiiii has fairly heavy hinder extremities, and the \ci'tcbi'a' of the back
and tail are strongly built: the femur, liowever, measures 1.2:! niel:ers
long, which indicates a comparatively small animal. P. saillcri has the
dorsal \('i1rhi'a' lighter and smaller, but with still highci- spines.

I'mli'iilala. — Of Predentate dinosaurs there have l)een found two
species of StegosauridiP and one small Ornithopod form. The details of
structure are not yet announced, but the Stegosaurs, neitlier of which is
large, have a dermal ai-nior consisting of "very strong spines, compared
to which the bon\- plates seem almost to lose significance."' As the latter
are perhaps the most chai-acteristic feature of the genus Sterjosaiinis it-
self, the infei-eiice is thai the African forms are representations of a
different genus; but we must await the conclusions of Doctor Hennig,
who is describinu' them, before an opinion as to tluu'r affinities can he

■' Doctor Matthew beUeves that these African forms probably did not much exceed in
.size those of America.

330 R. S. LULL SAUROPODA AND STEGOSAURIA OF THE MORRISON

ventured. The small Oruithopod genus is described as similar to the
American Laomurus and the English Ilypdlophodon. Laosaurus is a
well defined genus from the ]\rorris()n and Potomac formations, Avhile
ni/psilophodo7i is a persistently primitive type from the English Wealden,
llie only Predentate dinosaur with teeth in the premaxillary hone.

Stratigraphically I can find no record of the level wherein (li(/anl<)-
smiriis was found, as Fraas did nut clearly differentiate tlic three dinosaur
beds, but speaks of tlic dinosaur liorizou as though theie wen.' hut one.
Both species of Braclniomiinis. tlic Stegosaur (Hiarry and the hirger/iF
the two Dicrajosaiirs, are in the middle l^eds, while JHrid'/jsaurtis salUcri
is from the upper one. This places the Brachiosaurs, which are the
dinosaurs of greatest present utility for comparison with the American
types, in the strata which can be most surely dated, as they lie between
the two marine horizons, and thus both the upper and lower limit can
be fixed.

Unfortunately at this writing J eau not obtain a report on the marine
invertebrates of the Tendaguru, ahhough such luive Ijeen published by
Hennig and others. The reviews of two of these pa])eis in the Geo-
logisches Zentralblall (.June 1. 1!I14) contain certain inconsistencies
wliich are difficult to reconcile without reference to the original works.
The evidence, however, subject to future correction, seems to be as
follows :

1. Trigonia scliwarzi zone (Lower-Middle Neocomian).

I. Upper dinosaui' horizon — upper Tithonian to lowest Xco-
comian; somewhat of Wealden — Wealden plants.
"2. Trigonia smeei zone — typical Tithonian — in ])art uppermost Tviui-
meridgian.

II. Middle dinosaur horizon — Lower Kimmeridgian.
3. Nerinpa zone — Oxfordian.

III. Lower dinosaur horizcni — J^ower Uxfordian to Ivelloway.

The upper dinosaur beds seemingly belong faunally. florally. and as
regards facies to the Xeocomian or Wealden.

If this evidence be correctly interpreted, it places the majority of the
dinosaurs, the horizon of which is known, between Upper Jurassic marine
beds and those of the Comanchian, while the highly specialized Dirrwo-
saurus sattleri is of still younger Comanchian time.

WEALDEN

Sawopoda. — England and northern France particulaily liave produced
a long generic list of Sauropod dinosaurs, most of which are founded on

GEOGRAPHIC AND GEOLOGIC DISTRIBUTION 381

very imperfect material; this, in the case of dinosaurs particularly, ren-
ders comparative study a matter of extreme difficulty and is apt to give
rise to complications of synonymy. The best comparative study of Old
and New World Sauropoda which I have seen is that by Professor Marsh,
a summary* of which was first published in 1889, and later in "Dinosaurs
of North America," in 1896 (page 185). In studying the European
types. Marsh was impressed Ity throe prominent features in the specimens
investigated :

"(1) The apparent absence [in Europe] of any characteristic remains of
the Atlantosauridne. which embrace the most gigantic of the American forms.

"(2) The comparative abundance of anotlier family, Cardlodontld;ie (Cetio-
saurkhB) nearly allied to the Morosauridai, but as a rule less specialized.

"i'i) The absence, appai'ently, of all remains of the Diplodocid*.

"The most .striking difference between the Cardiodontidae and the allied
American forms is that in the former the fore and hind limbs appear to be
more nearly of the same length, indicating a more primitive or generalized
type. Nearly all the American Sauropoda, indeed, show a higher degree of
specialization than those of Europe, both in this feature and in some other
respects."

At least two American genera of Sauropoda have been recognized in
Europe, but the identity in each instance seems open to question. These
genera are Morosaurus and I'lcuvocoelus, the former a typical Morrison
form, having been reported I'rum the Oxfordian of Ourem, Portugal, and
from the Wealden of England. Pleuroccelus, a genus which includes the
smallest ol' the Sauropoda, has hut a single rare Morrison species referred
to it, while two forms, PleuroraduH nanus and P. alius, are known from
the Potomac formation of Maryland. There is reason to l)clieve that in
tlic (irst of the Maryland species at least the fore limbs were nearly equal
to tlic hiiiil ill Iciigtli. aiul in other respects, as well as in its relatively
siiuill size, tlu' creature was of primitive type. Bofliriospondylus, de-
sci'ilicd l)v Sir liicliard r)\v('n. from the Kimmeridgian of England, was
lliought Ity Marsh to I'cpi'cscid a \ery young, if not foetal, individual,
wiiich miglit he nearly allied to Pleuroccelus, while species from the
Wealden of Caen, France, and the Aptian of Portugal are- referred to the
'American genus itself.

There are, so far as 1 know, no generic comparisons to he made be-
tween the p]uropean Sauropo(hi and those of Tendaguru, although the
name Giganlosaurus a|)pears in each faunal list, but apparently applied
to forms wliicli ;ire not congeneric. On the other lumd, it is difficult to
make comparisons with the ^Torrison ty|ics A\liich wouM he of strati-

<Amer. Jour. Sci. (3), vol. xxxvll, pp. 323-331.

332 R. S. LULL SAUROPODA AND STEGOSAURIA OP THE MORRISON

graphic xalue, as the only genera which may possibly be common to both
faunas are comparativeh' generalized ty])es, neither of which is confined
to a single geologic level in Europe nor, in the case of Morosaurus, in
North America.

Stegosauria. — The European Stegosaurs include at least two phyla;
of these the one represented by the small spinescent Polacanthus of the
Wealden has no known Morrison equivalent, the group not appearing in
America until the Lakota, possibly still later in time. Of another phy-
lum, which included the American genus Stegosaurus itself, there seem
to be Old World representatives in Omosaurus durobrivensis, of which
the type specimen preserved in the British Museum is from Lhe Kim-
meridgian and shows great similarity to Stegosaurus in the character of
the veitebra? and in the presence of the expanded armor plates, the chief
distinction being the appearance on the femur of a well defined, crest-
like fourth trochanter in durohriveynsis which is obsolete in the several
American species. A second specimen in the Woodwardian Museum at
Cajnbridge, although labeled Omosaurus leedsi by Seeley, has also been
referred to 0. durobrivensis by A. Smith Woodward. The two specimens
are very similar, and associated with that of Cambridge I saw a very
characteristic caudal spine in addition to the armor plates. This latter
species is from tlie Oxford clay of Felton, and therefore, if the level be
correctly stated, froiii the Michlle Jurassic, in neither of these Old
World forms ha\e the xertebrte reached the degree of specialization found
in the Morrison types, and T should consider the reduction of the femoral
trochanter in tlie latter an cNolutionary advance as well; for, as Dollo has
shown, its ])resence is correlated with a bipedal gait which was secondarily
lost ill the Stegosaurs.

The evidence from tlie European Stegosaurs, therefore, can not be
taken as indicative of correlated age, Init, as I read it, simply points to a
greater anti(niity on tlie ]tart of Oxfordiaii nnd Kimmeridgian members
of the grou}).

MORRISON

Tlie American Moi'rison contaijis the greatest profusion of Sauropod
dinosaurs which any formation or locality has produced. Of the five
families recorded, one, the Atlantosaurid*, including perhaps the best
known members of the suborder — AtJaidomurus, Apatosaurus, and
Jlrontosaurus — is exclusively American. Nearest this family stand the
]\rorosaurid;e, smaller forms the stature of whose greatest member is but
two-thirds that of Bronlosaurus. The genus Morosaurus includes five or
six American species, of which all but one, which has been identified

SUMMARY 383

from the Trinity sands of Oklahoma, are Morrison, As I have stated,
Morosaurus is apparently represented in Europe by forms from the Mid-
dle Jurassic (Oxfordian) of Portugal and from the English Wealden.
None of the family has been recorded from Tendaguru. An allied family,
the Pleurocoelidae, which includes the rather primitive dinosaur Pleuro-
ccelus, is sparsely represented in the Morrison, more abundantly in the
Potomac and in the Wealden of England and Aptian of Portugal. I
should not consider the representatives of either of these families abroad
of any great stratigraphic value; so that, as these are the only genera
common to both Europe and North America, the Sauropoda throw little
light on the age of the Morrison in terms of European stratigraphy. But
the remaining families of Morrison Sauropoda — the long, slender Diplo-
docidae and the robust Brachiosaurida' — represent two extremes of spe-
cialization and therefore, as they are known with a high degree of com-
pleteness, should be of marked importance as correlating fossils.

Tlie Diplodocida?, including the single genus Diplodocus. with its two
or three American species, is unknown elsewhere, unless, as the Tenda-
giiiu authorities believe, the family is represented in that fauna by
GigantoxaurHs of Fraas. At all events, tlie comparison is not sufficiently
close to be of more than corroborative value. Tbe last family, tlie
Bi'achiosauridse, or Barosaiiridiv, as perhaps it slioidd be called, in-
cludes tlnvc American genera — Braclilosunnis Riggs, HaplocdniJiosfdinis
ilatclicr, and liarosaunis ^laisli — wliich, as Doctor Matthew lias sug-
gested, may i)e tlie same as Bnuliiomiirus, in which case the older name,
BdiDsimrns. takes ju'ccedence. Of these HapJocanthosaunis is evideiitlv
exclusively American, but Bracliiosaurus, as I have emphasized, includes
not only the American, but at least two well defined Tendaguru species
also. The Morrison Brackiosaurus comes from a horizon which, accord-
ing to Riggs, contains \ari(»us species of Apatosaurus (^ Brontosaurus)
and Morosaurus.

Tbe only Stegosauis tluis Far recoi-decl fi'om the ^foi-i'ison belong to
tbe genus Stegosnunis. with thix'e di' I'our species, and to the closelv
;illied. if not identical. Diracoilon. .\s I have slioMti, Stegosaurus seems
to he i-e|)i-esented hy species, piohahly ancestral, from the OxCoi'dian and
Kimmeridgian of l*]ngland, l)nl ii|>|iai'ent ly is very ditl'd'ciit I'lMm the so-
called "Stegosaiirs" of Tendaguru.

Sim .m \i;y

The conclusions 1 would diaw tVom this |ii-eliminai'v stud\- of the
|ii'olilem sei-\c to emphasize the ilillicidt\ of accurate comparixin of fossil
rei)tiles of huge size when we lia\c only \ery iucomplete matci'ial. whicli

334 R. S. LULL^ SAUROPODA AND STEGOSAI RIA OF THE MORRISON

may not include common elements on which to rely, and this is the chai-
acter of almost all of the European Sauropod remains.

On the otlier hand, one highly specialized genns is common hoth to
America and Tendaguru, and here the comparison may be based on rela-
tively perfect material.

With the Stegosaurs, opportunity for more perfect comparison lies be-
tween Europe and America, but only points to the conclusion that the
Morrison beds which contain the American type are relatively newer
than those which include the English relatives.

Correlation based on the Sauropod evidence between Europe and
America is not to be relied on at j^resent, but w"e can evidently pornt to
the middle Tendaguru horizon of East Africa, which contains the genus
common to the Morrison, as homotaxial with the latter.

As this middle bed at Tendaguru is bounded above and below by marine
sediments, the study of their contained faunas, which doubtless can be
definitely dated, should serve to determine the age of the ilorrison forma-
tion of iSTorth America. From the evidence so far at hand, the age of
this zone is certainly not older than uppermost Jurassic, with a decided
likelihood that the invertebrate writers will agree on an early Coinanchian
(Neocomian) time.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Vol. 26. pp. 335-342 AUGUST 17, 1915

PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

PALEOBOTANIC EVIDENCE OF THE AGE OF THE MORRISON

FORMATION '

BY I'DW.VIJD WILBER BERRY^
(Read before the Paleniifolor/iral Sociefi/ Deceuiher -U). V-HJf)

CONTENTS

Page

I iitroductory 335

Age of the I'otomac group 336

Age of the Wealden 338

Age of the Kootenai 338

Summary 341

Introductory

1'lie only fossil plants that have been recorded from the Mon-ison for-
mation are the silicified fragments of cycad stumps which occur in such
abundance in the Freezeout Hills of Carbon County and at one or two
other localities in Wyoming. These were described by Ward- and re-
ferred to the genus Cycadella. About a score of so-called species which
were based on external appearance were described. Neither the genus
{('jjcadellu) nor aJiy of the species have ever been found outside the
Morrison formation, so that they furnish no direct evidence regarding the
age of the deposits. They are, however, very close to the similarly silici-
lieil trunks of Cijcadeoidea in their habit and general plan of organization.
The Cycadeoidea remains are common in the Lakota formation oL' the
Black Hills rim and in the Patuxent formation of Maryland. In the
absence of studies of the internal structure of the Morrison genus Cyca-
della.it is not certain that it can ))(> nuiintainod as distinct from Ci/rn-

' Contribution to the symposium held at the Philadelphia meeting December 30, 1914.

Manuscript received by the Secretary of the Society April 3, 1015.
-Li. W. Ward: Description of a new genus and twenty new species of fossil cycadean
Ininks from the Jurassic of Wyoming. I'roc. Wash. Acad. Sci., vol. i, 1000, pp. 2r.:{-300.
.Iiir!issi<: cycads from Wyoming. Mon. U. S. Geol. Survey, vol. xlviii. lOOO, pp. 170-
203, Ills, xlvi-lxlil.

836 E. W. BERRY AGE OF THE MORRISON FORMATION

deoldea, the at present most (listiiietive feature of the former being the
profuse development of the ramentum, doubtless to be correlated with
some local climatic variation, and scarcely of generic magnitude.

The most important paleobotanie evidence bearing on the age of the
Morrison formation is to be derived from a consideration of the floras of
the Potomac group of the Atlantic Coastal Plain and similar Lower Cre-
taceous floras in other areas. That the composition and age of these
floras has an important bearing on the age of the Morrison will, I think,
be admitted after the relation of the fauna of the Morrison formation
and the flora of the Kootenai formation to the fauna of the Arundel for-
mation and the flora of the Patuxent and Arundel fornuitions has been
discussed.

Age of the Potomac CT^orp

Before making these comparisons it will be necessaiy to recall the evi-
dence for the Lower Cretaceous age of the various formations of the
Potomac group, since this also furnishes a strong argument for the
Lower Cretaceous age of the Wealden, at least for the Lower Cretaceous
age of the knoA\Ti Wealden floras.

The Cretaceous age of the Potomac group is indicated

(1 ) P>y the absence of any nuirine Jurassic deposits in Xorth America
east of the Mississippi Piver and the consequent imjjlication that tbi-^
eastern area was above sealevel during all of the Jurassic period.

{'I) By the presence of a wide-spread peneplain (Weverton), indi-
cating a long jjeriod of erosion, during which tbc eastern TJnited States
approached baselevel and on the tilted surface of which the sediments of
the Potomac grouj) wei"e deposited.

(3) By the evidence of deep weathering of tlie crystalline rocks which
supplied the materials of the Potomac formations.

(4) By the demonstrated synchroneity of the older Potomac floras —
that is, of the Patuxent and Arundel formations — both individually and
as a imit, with floras elsewhere, notably in easteni Asia, in South Amer-
ica, and in Portugal, where the floras are intercalated in a marine series
of more or less abundantly fossiliferous deposits whose age is unques-
tionable.

The details on which this last assertion of synchroneity is based need
not be repeated in the present connection, since they have been recently
given. ^ It will suffice for the present discussion to say that it rests on
all the facts entering into the question of correlation. Each sliows essen-

" E. W. Berry : liOwer fretaceous floras of the world and correlation of the Potomac
formations. Maiyland Oeol. Survey, Lower Cretaceous. PJll. \)\). !)0 172.

AGE OF THE POTOMAC GROUP 337

tially the sanu' surviving g-eneric types from the Jurassic, the same new
generic types, hoth those peculiar to the Lower ('retaceoiis and tliose fore-
shadowing later Horas, and a similar specific variation in the genera.
The common genera are numerous; the common species are more nu-
merous than might be expected, and finally the closely allied species are
very numerous.

One additional fact should be emphasized in connection with the flora
of the Potomac group, since it has an important bearing on the age of
the Morrison fonnation. This is the essential unity of the floras from
both the Patuxent and Arundel formations and their contrast with the
flora of the overlying Patapsco formation. An analysis of these three
floras develops the fact that the Arundel formation has only furnished
five species (in five genera) not present in the underlying Patuxent, and
four of these five genera are represented by closely allied Patuxent s])ecies,
while the fifth has closely allied forms in the Barremian and Ajjfian of
Europe.

The Potonuic reptilian fauna, which all vertebrate paleontologists have
compared with that of the Morrison, is found in the Arundel formation
unconformably overlying the Patnxent formation, which is from 200 to
400 feet in thickness. The hist authoritative study of the Arundel fauna
was that of Lull, ])ul)lished in IIMI. The following conclusions are
quoted fi'niii his (•(Hiti'ihiitioii."'

"The fossil reptiles of the Potomac, while not so abundant in numbers or
kinds as in tlie Morrison of our Western States, nevertlieless compare very
closely with the latter, as nearly all of the Potomac genera and, in some in-
stances, very closely allied if not identical species are foinid in the West.

"A striking similarity also iirevails ln'tween the Potomac on the one hand
and the Wealden of Euroi)e on the othei-. while one important Maryland genus
is reported from a lower horizon than the Wealden and none from a higher
level.

"The dinosaurs represent all of tlie suborders, including two of the heavier,
megalosaurian carnivores, AUomurus and Creosaurus, and one of the lighter.
Compsognathoid type. Cahirus. The quadrupedal Sauroi)oda are represented
by at least one genus. ])ossibly two, /'Iciirocalus and AstrodoH, including two
or three species in all. while of the Orthopoda there are two, one the unar-
mored Drj/oxuurus, the other, I'rirotKxhui, evidently belonging to the armored
grou]) or Stegosauria.

"Tlie dinosaurs show none of the remarkabl(> over-specialization of the later
Cretaceous tyjies. but. on the contrary, reitresent the oi'der at the crest of the
evoluti(»nary wave before signs of decadence set in. Unfortunately, owing to
an almost utter d(>arth of terrestrial .Jurassic deposits, nothing is known ot
diiiosain-ian evohUioii in America from Newark time until we come to the

* K. S. Lull: The roptilia of lln' .\niinlcl l"<prmnti(in. Maryland Ccol. Siirvi'V. T.owor
C'rctaccoiis. liHl, pii. tT.'i-lTs.

338 E. W. BERRY A(JE OF THE MORRISON FORMATION

liorizou uuder consideration. In Europe tlie record, tliougli still meager, is
more complete ; but it represents in every instance more primitive types than
those of the Arundel Jnid the Morrison.

"The character of these dinosaurs, and of the crocodile as well, correlates
the beds wherein they are found absolutely with the Morrison (Como) of the
West. An accurate comparison with European formations is more difficult, as
the faunas have fewer forms in common. Pleurocalus is reported from the
Kimmeridgian as well as from the Wealden. but that from the former horizon
may readily ha^•e been ancestral to the Arundel type, although the European
material is too fragmentary to admit of a just comparison. Of the other
dinosaurs, the affinities seem to be entirely with Wealden forms, Gcrlurus
being found therein, while AUosaiirus compares in point of size and dentition
witli the Wealden Mcfjiilosaurus. DnjosaurUH has its nearest European ally
ill Hjii)Hiloph()(l(nt, again a Wealden type, and the ci'ocodile, GonioplioUs, is
i-eported from the Wealden and its marine eciuivalent, the Purbeckian, not
from the older Jurassic levels.

"The weiglit of this evidence would seem to place this fauna beyond tlie
Jurassic into the beginning of Cretaceous times."

Age of the Wealden

Whatever the present analysis of the Morrison faunas may indicate
their relationships to be, it is an indisputable fact that the current tra-
dition that the Morrison formation is of Jurassic age has had no other
basis in fact than the late Professor Marsh's lifelong opinion that the
European Wealden was UiDper Jurassic. Possibly the last word has not
yet been said regarding the age of the Wealden, but the consensus of
opinion of those best able to form a reliable judgment — that is, European
students of the Wealden stratigraphy — seems to be that the Wealden is
of Lower Cretaceous age, and for the following reasons:

1. Where the Wealden is present, the oldest marine. Lower Cretaceous,
is absent, and the Wealden may lie with a marked unconformity on the
Upper Jtuassic, as in the Boulnmiais.

2. Its tioiu is similar to the older Potomac flora (Patuxent and
Arundel), and likewise similar to Neocomian and Barremian floras of
known age, as determined by invertebrate paleontologists in Portugal,
Japan, and Peru.

The faunas of the AVealden offer little satisfactoiy evidence, since if
Lower Cretaceous they represent survivals from the late Jurassic, and
the comparable N'eocomian deposits contain marine faunas and lack both
terrestrial vertebrates and plants.

Age of the Kootenai

Turning now to a consideration of the Kootenai flora of the Eockv
Mountain jirovince, it may be noted that the flora of the Kootenai, as

AGE OF THE KO(yrENAI 339

partially revised by nie in my study of the Lower Cretaceous Horn of
Maryland and Virginia, comprises 86 species in 42 genera. Thirty-rour
of these genera occur in the Lower Cretaceous of the Atlantic Coastal
Plain.

Of these 86 recorded forms from the Kootenai, 13 are so poorly ])re-
served that they have never been specifically determined, although I'i of
the genera to which they are referred are commonly represented in the
Potomac. There are 31 species not yet discovered outside of the Xoolt'niii
deposits. These represent 24 genera, of wliich 18 ai'e iv])resentc(l in ihc
Potomac, several being confined to its uppermost foruuition, the l'ala])S(o,
which is clearly of Albian age.

Deducting the foregoing 44 species from the Kootenai total, there re-
mains 42 species, or nearly 50 per cent, with an outside distribution.
Before considering the significance of these forms \nth an outside dis-
tribution, there remains to be ruled out of the discussion the following
forms that are without stratigraphic or chronologic significance for the
reasons noted in connection with each:

Dawson identified two species of Ginkgo with forms described originally
by Heer from tlie Upper Oolite of Siberia. These really represent a
single species, and without the aid furnished by a known geologic horizon
they can not be distinguished from Ginkgo leaves found as late as the
Eocene. Another species, Podozaniites lanceolatus, possibly composite,
has a recorded range from the Jurassic to the top of the Upper Cretaceous
and is obviously of no value in correlation. Similarly Sequoia reichen-
bachi, also possible composite, has a recorded range from the Portlandian
to the top of the Upper Cretaceous, and has no chronologic value except
as indicative of Mesozoic age.

'fhis leaves 38 forms possessing chronologic significance. Twenty-five
of these occur in the Lower Cretaceous of the iVtlantic Coastal Plain,
and of these 25, 19 range from the bottom to the top of the Potomac
group, namely, from Neocomian to Albian, in terms of the standard
European section. Only five are confined to the older Patuxent and
Arundel horizons and 21 occur in the Patapsco formation, of Albian age
and overlvin"" unconfonnahlv the Arundel formation oi- horizon of the
I'otonuic reptilian fauna.

This, it seems to me, is an important fact, namely, that over 55 ])er
cent of the Kootenai species with an outside distribution are found in
the Atlantic Coastal Plain unconforinahly overlying the Potomas dino-
saurian fauna, which by hoth Marsh and Lull is said to show a distinct
Morrison character. Whatever modern nu'thods of comparison may make
out of this faunal resemblance, it was sufficiently marked, according to

840 E. W. BERRY AGE OF THE MORRISON FORMATION

Professor Marsh's interpretation, to jnstifv his astounding claim tliat the
Atlantic Coa.stal Plain Cretaceous, as liigli as beds that I correUite with
the Turonian and that AVeller correlated with the Senonian, are of
Jurassic age.

Xine of the Kootenai plants are found in the European Wealden, all
l)ut one of these being also common to the Potomac.

('(iiii|)artMl with floras which, on the basis of their iincileln'ati' faunas,
h;i\(' hccii I'd'ciTcd to ihc Ncocomian. we find two of tliese species in the
XiMicoiniau of Germany, six in tlie Xeocomian of Portugal, lour in tlie
Xeocoiniai) of Japan, two in the Xeocomian of Peru, and one in the
Xeocomiaii of Mexico. Compared with floras similarly determined as of
Barremian age, it may be noted that two of the Kooteiiai species occur
in the Barremian of Austria and fo\ir in the Barremian of Portugal.
Two of the species occur in the Aptian uf Portngal. In the European
Albian there is a common species in Switzerland and five additional in
Portugal. No less than nine of the Kootenai species survive as late as
the I'pper Cretaceous of Ja])an, (ireenland. P]urope (four species), and
the Atlantic Coastal Plain. They also find a representation in the
Ti'inity flora of Texas (two species), in the Fuson (five species) and
Lakota (six species) floras of the Black Hills, and in the Shasta (nine
species) and Horsetown (one species) beds of the Pacific coast.

Aside from the Potomac element in the Kootenai flora, the most promi-
nent facts bearing on its precise age are furnished by comparisons with
the Kome flora of western Greenland. There are 10 species, or 32 per
cent, of the Kootenai forms with an outside distribution that are common
to Kome. Seven of these, including two of the genera, are not found in
the Potomac flora, and seven are likewise confined to the Kome and the
Kootenai. In addition to the id-entical forms, there are a lunnber of
closely related forms in the two areas, and this Kome fades is so promi-
nent in the Kootenai flora that it is emphasized by Dawson, Fontaine,
and Ward. The age of the Kome flora is not positively determined as
to its upper limits, bnt it is clearly not older than Barremian. which is
the age assigned to it by Heer and by the Scandinavian and Danish
geologists who have studied its relations, and it may even be of Aptian
age.

The bearing of this conclusion on the age of the Morrison must be
obvious. If the Kootenai flora is of Barremian age, then at least a part
of the Morrison must be of Xeocomian age, since the Kootenai is either
partly the equivalent of the Morrison or, giving the utmost allowance for
the contrary opinion, the southern extension of the Kootenai is conform-

SUMMARY

341

able on the iiortliei'ii e.xteiisioii of the Morrison/^' This is in a iiieasiii-e
substantiated l)y the 'i') species that raii.^e ii|)\vai'<l iiil<> the Alhian ( I'a-
tapsco formation) of Man hind and \'ii',i;inia.

Summary

1. Both the W'eahh'ii and Potomac thuas, on ihe ground ol' the struc-
tural relations of the containing- \)rt\i^ and on the ground of their syn-
ehroneity with floras of othei' areas of a known st rat inrajihic position, as
determined by invertebrate ])aleontolo<iy, are refei'red to the Lower Cre-
taceous.

2. The eastern faunas, considered as of the same age as the Morrison
by Marsh, Hatcher, and Lull, are undei-lain by from '^OO to 400 feet of
Cretaceous sediments containing- a Lower Cretaceous flora which in the
l^ocky Mountain ])ro\ince is first found ii! the Kootenai formation, whicli
is partially equi\alcnt to or at most coufoi inable on the ]\Iorrison.

3. The Kootenai tloj-a appears to be most similar t(j the Konie floi'a of
Greenland, which is ]iot oldei' than Barremian and possibly somewhat
younger (perhaps Aptian).

i. If this correlation is correct, then at least some of the Morrison must
be of Lower Ci'efaceous age.

In conclusion, it seems to me that in discussions of this sort we should
not lose sight of the fact that human taxonomies ha\e no objective ex-
istence. 'J'hose of geology are at best units of a filing system, hy means
of which we arrange our knowledge of earth history. Tt would undoubt-
edly be less troublesome if we could interpret this history in the way that
Cuvier did.

As it is today, while we re])udiate Cuvier's catast I'ophics and I'cxdlu-
lions. all oui- ai'guments ai'e tinged with the ancient heresy that Moras
and, faunas developed almost intact up to a certain time, when, presto
change! — Jurassic inxcrtebi-ates were re|)laced by Cretaceous inveite-
brates. The last dinosaui- hd't the world as precipitately as the last Moor
quitted (irenada. oi' the Angiosperms sprang into existence like T'allas
Athene.

It is inconceivable to me that faunas or floras have even undeimuie
anything ol her than an orderly e\olution, except where i-elati\-ely sudden
changes (if cn\ ir(;iiment caused a \'ery local re|)lacement of the kind the
])aleontologist assumes (not theoretically, but in practice) was on a uni-
versal scale. Imcii llie laltci-h famed method (d' diasl i-oi)iiism is based

'• C. A. Fisher: Kconoriiical (ieology, vol. ill, 1908, p. 77. Bull. U. S. Geol. Survey,
No. 356.

342 E. W. BERRY AGE OF THE MORRISON FORMATION

on phenomena that must liave been essentially provincial in character and
not continental or cosmopolitan, and, furthermore, continued over long
periods of time. Presently we may expect some modern Huxley to
enunciate diastrophic homotaxis as opposed to diastrophic synchroneity.

I am not seeking to depreciate continued eifort to reach results, but I
M'ould wish that we all migbt be less dogmatic. The absurdities in the
liistorv of science arc not confini'il tn paleozoologist or paleobotanist ; ]ios-
sihly, since iinci'tcbi'nte i)alc()/,()()l()gy is older than vertebrate ])ale()zoology
or palcoholany. it still ictains nioi'c oi'iginal sin tlian the other two.

My closijig pica is. then. I'oi' less inrallihility and a bi'oadcr culture in
the scientific life.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Vol. 26, pp. 343-348 AUGUST 17, 1915

PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

INYERTEBEATE FAUNA OF THE MORRISON FORMATION ^

BY T. \V. STANTON"

{Read before the Pdleniihiluiiical Society December SO, 101.'/ >

CONTENTS

Page

Lists of described species 343

Comparison with other non-marine invertebrate faunas 344

Wealden fauna 344

Potomac fauna 345

Kootenai fauna 345

Bear River fauna 346

DalvOta fauna 347

Time limits of the Morrison formation as determined by associated marine

faunas 347

General discussion 347

Sundance fauna 347

Washita fauna 348

Lists op described Species

When, in 1SS(], C. A. AMiite- reviewed the invertebrate fauna of the
foi-inaiioii iiiiw known as Morrison, lie listed 2^ species, as follows:

Unio felchii White
Unio toxonotuH Wliifc
Unio macropisthus Wliitc
Unio iridoidcs White
Unio lapilloidcH White
Unio HtcirnnJi White
Unio nucdlis M. ^indH.

Vorticifex stearnsii White

Talvata scohrida M. and H.

1 ii'(/j«rM.S' fjilli M. and H.
*Lioplacodes veternus M. and H.
*Neritina nchrascensis M. and II.

MetacypriH forhesi Jones

Metacypris sp.

' Conlril)iilif)n to tli<» symposiiiin lif>l(l at the Philadelphia meeting December 30. 1914.
Manuscript receivctl h.v the Secretary of the Society April .". 1915.
Published by permission of the Director of the U. S. Geological Survey.
= C. A. White: Freshwater invertebrates of the North American .Turassic. U. S. GeoL
Survey Bull. 29, 1886.

♦ The two species marlied with an asterislc. from "near head of Wind River," probably
belong to a later fauna.

XXV— Bull. Gkol. Soc. Am., Vol. 26, 1914 (343)

344

N\-. STANTON INVERTEBRATE FAUNA OF THE MORRISON

Limnwa ativuncula White
Limnwa consortis White
Limnwa ? acccleratu Wliite
Planorhis vcternns M. and H.

Darwinula Icguminella Forbes
Gypris purheckensis (Forbes)
Cypris sp.

Of these, se\en species are referred to Vnio, three to Liinnaa, one each
It) Planorhis, VorHcifex, Valvata, Yivipanis, Lioplacoiles, and Neritina,
and five are ostracod crustaceans. All are of fresh-water habitat. More
than half of them come from a single locality near Canon City, Colorado.
Tlie others are I'cported from the Black Hills, from two localities in
southern Wyoming, and from the head of Wind Eiver, Wyoming, the
stratigraphic position of the species from the la-st-named locality being
doubtful. Logan^ has listed five species from the Freeze-ont Hills, south-
ern AVyoming, of which three species of Unio and a ^'a■h^ala are described
as new. The list is as follows:

Unio bailcyi Logan
Unio knighti T^ogan
Unio wiUistoni Logan

All from Fi'eeze-out Hills.

ValiHita led Logan
Planoybis vctcrnus M. and H.

T'^ndescribed collections fi'oni Morrisf»n, Colorado City, and Uncom-
paligre Valley, Colorado, from the Black Hills, from the neighborhood
of Como, Wyoming, aiul of Jensen, Utah, and J'loiu tlic Creat Falls and
Lewistown areas in Montana, have added to tlie Morrison fauna without
changing its essential characteristics until, as now known, it includes
about 30 species, practically all of which are referred to living genera.

Comparison w riii otieer non-Makixk ixvertebeate Faunas

WEALD EN FAUNA

From the statement tliat tlie fauna consists of fresh-water MoUusca
and Ostracoda belonging to modern genera, it is t'\ ident that it can offer
little direct evidence on the exact age of the Moi risoii foi-iiiation. Logan's
argument foi- convlatiiig tlie Morrison with the WCaldcii because, as he
says, "four of the genera — I'nio. \'iilv(tln. Flanuihis. and Viviparus —
which are represented in the two formations by species having practically
the same degree of de\('lo]»iiient are not known fi'oni older formations,"
is not valid because it does not agree with tlie facts of distribution as now
known, rnio. Planorhis. and Valvata are all known fioni formations
older than the AYealden. and the species of Unio from the Upjier Triassic

3 W. N. Logan : The stratigraphj- and invertebrate faunas of the Jurassic formation
in the Freeze-out Hills of Wyoming. Kansas Univ. Quarterly, vol. 9, 1900, pp. 132-1.34.'

POTOMAC AND KOOTENAI FAUNAS 345

oi' Te.xu.s and New Mexico appear to be as well developed as those from
the Morrison. It can not be jnstly claimed that there is anything in the
Morrison in\ertebrates themselves that precludes their reference to an
earlier epoch than the Wealden. They do not offer any evidence on the
correlation of tlie Morrison with the Potomac group wliicli has been ad-
vocated on the basis of the vertebrate fauna.

POTOMAC FAUNA

The live species of invertebrates which W. B. Clark' has named from
I he I'olomac are apparently all distinct from Morrison species, but an
examination of the published figures shows that they are all so imper-
fectly preserved that even their generic reference is very doubtful. The
forms described are as follows :

Unio patapscoensis Clark Viviparus arlinfjtonensis Clark

Ci/rena marylandica Clark Bythinia arundelcnsis Clark

All are from the Arundel formation except the Unio, which is from the
Patapsco.

l^'urthci- cDiiiiuu-ison of the Morrison i]i\ertebrates shows that specific-
ally and as a fauna they are decidedly distinct from all othei- fresh-water
fannas that are found geographically or stratigraphically near them. The
faunas wliicli deserve mention in this connection are those of the Koote-
nai, the Bear River, and the Dakota.

KOOTENAI FAUNA

in ^[oniaiia the coal-bearing Kootenai formation has yielded non-
niai'iiic in\crtehrates at many localities, bnt tliey lunc not Ijeen thoroughly
collected noi' fully descrihcd. From a locality about "i miles southeast of
TTarlowton T luive dcscrihcih"' the following six species:

Unio farri Goniobusis f silhcrUngi

Unio douglassi Goniohasis ? ortmanni

VivijHiius inontanaennis Campelonta harloivtoncnsis

When these species were described their exact stratigraphic position
was not known, but it has since been determined that they came from
the Kootenai formation, which in the (Jreat Falls field has yielded similar
fonjis, though not so well |n-csci\cd, together with a Nerilina and some
other species. The so-called hakota fossils of the Yellowstone National

*W. B. Clark: Lower Cretaceous, Maryland Geol. Survey, 1011, pp. 211-213.
* T. W. Stanton: A new fresh-water moUiiscan faunule from the Cretaceous of Mon-
tana. Proc. Am. I'hilos. Soc, vol. 43, 1903. pp. 188-199.

346 T. W. STANTON INVERTEBRATE EAI'NA OF THE MORRISON

Park probably also belong in this fauna. The only species that suggests
a Morrison form is the Viviparus. The other gastropods, and the Union
especially, are very distinct from those of the Morrison. The evidence
of the invertebrates, therefore, is opposed to Professor Berry's*' suggestion
"that this general horizon in the Eocky Mountain area has been regarded
as Morriso]] Avhere it contains vertebrate remains and Kootenai where it
contains plant remains."

It is still questionable whether Fisher and C^alvcrt wnc justified in
identifying the Morrison beneath the Kootenai in ]\Iontaiui. and it may
be that the beds which they so identified really form a basal member of
the Kootenai, as Fisher suggested. The dinosaur bones collected from
tills part of the section were not well enough preserved for even generic
identification, and fragments of bone were found at different horizons
throughout the overlying Kootenai formation. Tn this connection I call
the attention of vertebrate paleontologists to the fact that the Carnegie
Museum at Pittsburgh has a collection of dinosaur bones obtained by
Hatcher from supposed Kootenai at the locality near Harlowton, Mon-
tana, which yielded the invertebrates here listed, and it may be that there
is another collection of them at I'rinceton University. Possibly these
are good enough for determining whether or not they are distinct from
Morrison forms. That post-Morrison formations do contain dinosaurs
related to those of the Morrison is shown by the occurrence of IToplito-
saurus and Camptosaurus in the Lakota near Buffalo (lap, South Dakota,
as recorded by Gilmore.' For this reason the finding of a bone of an
unidentified saui-o])od dinosaur in the Comanche series of Oklahoma has
never seemed to me very strong evidence that the Morrison is of Co-
manche age. If some groups of Morrison diiiosaiii's ranged into later
formations, the sauropods also may luive had a greater vertical range.

BEAR RIVER FAUNA

The Bear Pivc-r fauna occurs in a thick formation at tlie base of the
Upper Creta;ceous in southwestern Wyoming. It is a large and greatly
varied fresh-water fauna, with a few brackish-water species, which has
been fully described by C. A. White.* It shows no relationship with the
Morrison fauna other than a few conmion genera, and its resemblance to
the Kootenai fauna is but little closer.

'E. W. Berry: Lower Cretaceous, Maryland Geo). Survey, 1911, p. 164.
■^ C. W. Gilmore : Proc. TT. S. National Muspud). vol. .36, 1909, p. 300.
* C. A, White : The Bear River formation and its characteristic fauna. U. S. Geol.
Survey Bull. 128, 1895.

DAKOTA AND SUNDANCE FAUNAS 347

DAKOTA FAUNA

The Dakota fauna, as described'* and as represented in collections, is
small but complex. Eliminating the Comanche species from the neigh-
borhood of Salina, Kansas, which were described as Dakota by Meek,
there remains a number of fresh-water species, some of which are related
to those of the Bear Eiver, and several brackish-water and marine mol-
iiisks which show relationship with the succeeding Benton fauna. None
of the fresh-water species suggests derivation from Morrison forms.

Time Limits of tiik Morrison Formation as determined by asso-
ciated MARINE Faunas

GENERAL DISCUSSION

The Morrison fauna tben stands by itself, distinct from the few fresh-
water invertebrates that preceded it in the Triassic and distinct from the
non-marine Cretaceous faunas which followed it. Of course, there is no
basis for comparison with the marine faunas which are nearest to it in
time, but the study of these marine faunas serves to fix definitely the
time limits within which the Morrison formation must fall.

SUNDANCE FAUNA

The lower limit is fixed by the age of the marine Jurassic Sundance
formation on which the Morrison rests in southern Wyoming. The
Sundance is classified as Upper Jurassic, and for that reason it lias been
assumed by some geologists that everything above the Sundance must be
post-Jurassic. But a study of the fauna of the Sundance shows that it
is liy no means the latest Jurassic, but that it belongs in the hjircr ])art
(if llic Upper Jurassic. It is characterized by Cardioceras conlifoniir
jiikI (ilhcr iiiM'rtebrates, which indicate approximate correlation with llie
Oxfoidian of the European Jurassic. In Europe the Oxfordian is fol-
lowed by hitiT Jurassic sediments, classified by De Lapparent as Se-
<|uanian, i\ immeridgian, and Portlandian (including Purbeckian). In
Ahiska. also the fauna most closely related to the Sundance fauna occui-s
in l)('ds which arc o\ci-lain by several thousand feet of lalci- Jurassic
sli'ata. 'J'here is ample i(join, therefore, for tlie Morrison within the
Jurassic.

The incursion of the sea which resulted in the deposition of the
Sundance formation and its e(|ui\alcnts in the Koeky Mountain region

» F. B. Mepk : U. S. Geol. Survey Terr., vol. 9, 187G.
('. A. WliU(> : I'roc. U. S. National ^f^ls^Mlm, vol. 17, 1894, pp. 131-138.

348 T. W. STANTON INVERTEBRATE FAUNA OF THE MORRISON

was a comparatively brief episode in the long period covering a large part
of the Mesozoic era dnring which continental conditions prevailed. If
the retreat of this sea was immediately followed hy a long period of uplift
and erosion prior to Morrison time, the evidence of it seems to have been
overlooked by geologists. There is evidence that there was erosion and
baseleveling before the marine Jurassic was laid down. On the assump-
tion that marine waters were finally withdrawn from the Sundance sea
either by a slight general uplift or by the silting up of the shallow basin,
it is not unreasonable to suppose that the formation of continental de-
posits like the Morrison might begin almost immediately over the same
area and extend far beyond it. The alteniative hypothesis requires a
considerable interval between the Sundance and the ^rorrison ap])arently
unrepresented by either deposits or erosion.

WASHITA FAUNA

It is not within my province to speak of the possible upper limit of the
Morrison as determined by the age of the floras in the overlying Kootenai
and Lakota formations of Montana and the Black Hills. The oldest
overlying marine fauna is found above the southern extension of the
Morrison in southeastern Colorado, northeastern New Mexico, and north-
western Oklahoma, where the Morrison, with its characteristic dinosaurs,
is overlain by beds containing the fauna of the Washita group, which is
the uppermost of the three groups forming the Comanche series. In
America it has been customary to classify the Comanche series as Lower
Cretaceous in contrast with the great Upper Cretaceous series beginning
with the Dakota sandstone. A number of European paleontologists who
have given some attention to the Washita fauna l)elieve it to be of Ceuo-
manian age, the Cenomanian being regaidrd as tlie base of the Upper
Cretaceous in Europe. This determination being taken as the latest
possible assignment of the overlying beds, the Morrison must be older
than Cenomanian and probably younger than Oxfordian. That it repre-
sents all of tliis interval is not probable, but in my opinion the lithologic
and stratigraphic evidence of a break in sedimentation is fully as great,
if not greater, between the Morrison and the rocks of Washita age, where
they are in contact as it is between the Moi-rison and the Sundance in the
northern area where these two formations come together. So far as
stratigraphy and invertebrate faunas are concerned, the Morrison is some-
what more likely to belong to the diirassic ])()rti()n of the interval just
indicated than to the Cretaceous portion; but tbcir e\ idence is not con-
clusive on this point.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Vol. 26, pp. 349-374, PLS. 10-15 AUGUST 17, 1915

PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

STUDIES OF THE MOEPHOLOGY AND HISTOLOGY OF THE
TEEPOSTOMATA OR MONTICULIPOROIDS ^

BY E. R. CUMINGS AND J. J. GALLOWAY

(Read before the Paleonlological SocicUj Deceinher 31, 19 IJ/)

CONTENTS

Page

lutroducLioii 349

Cysts and cystiplu-agin.s 350

In general 350

Infimdihular diaphragiiis 351

Cysts and brown bodies 351

Alternative explanations 353

Communication pores 356

Intrazocecial spines 358

Wall structure 358

Integra ta and amalgamata 358

Histology of the walls and tlic median line 359

The ciiigulum 361

Acanthopores 363

Merlia noriiiani Kirkpatrick 364

Summary and conclusions 365

T'.ililiograiiliy .366

lOxpl.iiiatioH of jilates :]QQ

Introduction

The rt'sults recur<le(l in the present papei- are the by-])ro(luct of studies
i)egun liy tlie senior author in 18!»9, and since 1908 sliared by both au-
thors on even terms. At first dur interest in the order was ahnost entirely
faunistie and systematic;, but as these studies were pushed further it be-
came more and more evident that a much nioi'e detailed and minute
examination of trepostome structure was necessary to the proper elucida-
tion of generic and family relatiiiiishi|)s. It was necessary, liowevcr. first
of all, til lii'iiig to a conclusive issue the vexed question of the .systematic
j)osition of ibe group, and failiiiL:" this from the direction of nioi-pliolngv

1 Manuscript received by the Secretary of the Society April 3, lOlIi.

(349)

350 CUMINGS AND GALLOWAY MORPHOLOGY OP TREPOSTOMATA

alone, the problem was finally successfully attacked from the standpoint
of colonial development (astogeny). The senior author's paper on the
development of the Trepostomata (8)', published in 1913, leaves no
doubt of the Bryozoaii affinities of the order.

The results presented now are only a part of the mass of exact data
that has accumulated during these years. All of it is confirmatory of the
relationsliips ijidicated by development, and has led us to express a de-
gree of confidence in our interpretations of certain peculiar structures
that, in the absence of such conclusive evidence, we could not have had.

Nearly all of our knowledge of the morphology of the Trepostomata
has been gained through the work of Nicholson (22-25), Ulrich (28-3J:),
ITlrich and Bassler (35), Bassler (1^), and the writers (6-10). In
this list the name of Ulrich stands preeminent. Had the internal struc-
ture of recent Bryozoa been studied with equal thoroughness our problem
of the interpretation of trepostome structure would have been very greatly
lightened. As it is, we are still left in the dark in regard to a number of
points. We have, to be sure, the works of Milne-Edwards, Busk, Waters,
Nitsche, Hincks, Smitt, and Harmer, and especially of Calvet and Lev-
insen. Nevertheless, one still looks in vain for an elucidation of colony-
building in the recent Bryozoa, such as the absence of soft parts has made
necessary in Paleozoic forms.

For example, the exact manner in which the interzooecial wall must
have been built up in the Trepostomata is beautifully revealed in the
illustrations accompanying the present paper ; but of the manner in which
the interzooecial wall is actually built in recent Bryozoa most closely re-
lated to the Trepostomata, namely, in Heteropora and in the Cyclosto-
mata, we know little. It will be necessary to study the recent Bryozoa ■
by the meth(tds now employed with such success in the study of the
Paleozoic Bryozoa. Until this is done some points at least must remain
obscure.

Cysts and Cystiphragms

in general

One of the most striking, and indeed one of the most extraordinary,
features of the Trepostomata is the structures known as cysti]:)hragms.
Cystiphragms occur rt^gularly in several genera and sporadically in many
others. In MonticuUpora, Tlomotrypa, Peronopora, Tlomotrypella, etcet-
era, these structures are invariably present and preeminently character-
istic. In Amplexopora, Baiostoma, Heterotrypa, TIallopora, etcetera,
they are usually absent. In fact, structures exactly like cystiphragms in

- Figures in ( ) refei- to bibliography on page 366.

CYSTS AND CYSTIPHRAGMS 351

appearance, when seen in the genera last named, have been denied the
name of cystiphragms and liave been spoken of as curved diaphragms.
We hope that we shall be able to show that in l)()th cases these structures
are tlio same in origin and function, and that the difference is only a
matter of the regularity of their occurrence. AW' sliall suggest an inter-
pretation of cystiphragms in the light of certain associated structures,
here described for the first time.

INFUNDIBULAR DIAPHRAGMS

The sti-iictures referred to are illustrated in liguies 1 to 22, inehisive.
Many years ago Ulrich (30) figured and described "infundibular dia-
phragms" in Amplexopora rolnista and .1. cingulata. We have not ex-
amined the sections on which his descriptions were based, but there can
be no doubt, after an examination of his figures and the figures presented
herewith, that he was dealing with the same structures, but failed to see
that the infundibular diaphragms are in reality the upper portions of
complete, bottle-shaped or vase-shaped cysts, and that in every case these
cysts inclose a mass of bro^vn granular material unlike anything ever
seen in any other portion of the zoarium. The brown material and the
cysts are never present in the mesopores of species in which mesopores
occur.

CYSTS AND BROWN BODIES

Tlie portion of the cyst that envelops these brown masses is usually
excessively thin-wailed and may easily be overlooked. Tt may be best
studied with a 4 nnn. objective in sections cut very thin (about 25 mi-
crons). The cyst and its narrow neck (nl- in the figures) is usually
I'onnd in cross-section, as shown in numerous tangential sections. Tn
lleterotrypa singularis and !T. suhramosa there are thousands of these
cysts. They are found in greater or less perfection in many other genera,
and especially in Amplexopora, Batostoma, Peronopora, Homotri/pella,
Monticulipora, Prasopora, Homotrypa, AiactoporeUa, Aiactopova, etcet-
era. In Homotrypa they are very rare, but in the other genera of tlie
family Monticuliporida' {seiisu slrichi) they are common, in many
cases the cyst is imperfectly developed, and tlie brown mass is then asso-
cialcd with I he cN si i|»hi'aL;nis and diaphiagiiis. hul alw a\ > in a \crv special
way. This latter ai'raiigeinrnt is best show ii in Pcrdiiiiimni (ligures IS.
20, 22). In forms that iioi'mally have a lai'g(> numhcr n\' cvstiiihragins
a |n'rfc((ly foinie(| cyst, such as is so coninnin in II I'lcrnl nj pit . is seldom
seiMi.

Tiu' special rclationsliips of the brown material and the cystiphragms
and diaphrjignis ai'e as f(dlnw> in rcnnidjuini ((ignres IS, •jO, 22):

352 CUMINGS AND GALLOWAY MORPHOLOGY OF TREPOSTOMATA

The proximal portion of tlie brown mass rests usually on a well defined
diaphragm, and the mass itself occupies the space between the cysti-
phragms and the opposite wall of the zooecium. Often near the top of
the brown mass the cystipliragms line the zocecial tube all the way round,
so that the constricted space left between them forms a narrow neck.
Tangential sections show that this neck is usually of tubular cross-section.
A short distance above (distally to) this neck there is another well de-
fined diaphragm, and above the latter diaphragm, in turn, there often
appears (in Peronopora usually) another brown mass, with a repetition
of the succession of cystiphragms, etcetera, as just described.

The arrangement of cystiphragms and diaphragms, just described,
characterizes the Monticuliporidse, in which cystiphragms are a normal
feature. A precisely similar arrangement is sometimes seen in Batostoma
(figure 10) and in Heterofi ypa (figures 2 and 6). The relative posi-
tions of brown mass, cystiphragms, and diaphragms are identical. In
these latter genera, however, the brown mass is usually surrounded by a
well defined calcareous cyst, of which the typical cystiphragms constitute
only the neck region (figures 3, 4, 5, 7, 11, and 14). Other figures show
various arrangements intermediate between the two. In some cases the
proximal end of the cyst is separated more or less from the basal dia-
phragm {d' of the figures). This is shown in figures 1, 3, and 7.

The neck of the cyst is nearly always clear and free from the brown
material. It may be open above — that is, with a considerable clear space
between it and the distal diaphragm (figures 2, 4, 14, etcetera) — or it
may be securely stoppered l)y a diaphragm of greater or less thickness
(figures 1, 9, 11, etcetera). Occasionally the neck contains foreign parti-
cles that can be very easily distinguished from the peculiar brown ma-
terial. As shown in a number of the figures, the wall of the cyst is con-
tinuous, distally, with the inner tenuous lining wall of the zooecium.
Tlie space between the cystiphragms and the main zocecial wall, or be-
tween the neck of the cyst and the wall, is absolutely empty, never show-
iyg anything but clear, well crystallized calcite, with which it has, of
course, become infiltrated during fossilization. That this space was
originally merely a void between the endosarc of the polypide and the
interzooecial wall is certain.

The nature of the brown material is as suggestive as its position and
relations to surrounding structures. It consists of minute rounded par-
ticles from a seventy-fifth to a hundredtli of a millimeter in diameter, of
a dark yellowish brown color, as seen by transmitted light, and marked
by lighter bands, as shown in figure 31. These particles consist of

CYSTS AND CYSTIPHRAGMS 358

niiiiutu coiieretioiKs of some iron compound. They react for both ferric
and ferrous iron.

In figure 40 is shown the space actually occupied by an individual
polypide. The space occupied by a brown mass and its accompanying
cyst or cystiphragms — that is, the space between the distal and proximal
diaphragms — is the same as the space occupied by an ordinary polypide.
Taking into consideration, therefore, the size, relations to surrounding
structures, nature of the material, and its isolation, there can be no doubt
that the brown material is due to the replacement, probably by iron sul-
phide or iron sulphate, of organic matter left in the zoa'cium after the
death of the polypide.

ALTERNATIVE EXPLANATIONS

Either this is the case or we must suppose that material injested by
the polypide during life has been left in the abandoned zoa'cium. We
have failed to see any good evidence that the latter is the case, although
there is some analogy for it among the recent Bryozoa. ''I'he appearance
of the brown mass and its enveloping cyst is curiously suggestive of the
brown body so characteristic of recent Bryozoa. One can not be too
careful about being misled by such resemblances; nevertheless there are
certain considerations that make it seem to us worth while to suggest the
possibility that these cysts and their invariable accompaniment, the brown
mass, may actually lia\e been produced in connection with brown bodies.

First of all, let it be distinctly understood that the brown color of these
masses, in the fossil forms, has no relation whatever to the In'OAvn color
of tlic oi-igiiial bi-own body; nor is the material, in its present form, in
any way simihii-. If there is any relati(ni between the two, we must su])-
pose thiit tlie oi'ganie matter of the original bi'own body caused the segre-
gation of some iron compound during the decomposition of the former
in ihr ahandoncil zon'ciuni. There is plenty of wari'anl among fossils
\<tr such a supposition. It might also be possible that material absorbed
liy the polypide I'l'om solution oi- suspension in the sea-watei' in which it
was li\ing has been excreted and left hehind in the Z0(jecium, after the
manner <if the excretion of Bismarck brown and other reagents, as de-
seril)ed by Hamier (1.'5). AVe should also have to suppose that after the
polypide degenerated into a In-own l)ody the endosarc withdrew or re-
treated from the zort>cial wall and formed a new ectosarc enveloping the
degenerated polypide. Foi- the deposition of a calcareous cyst about the
brown body there is no analogy among the recent l-^ryozoa, so fiir as we
are aware; neither is Iheie any analogy for such structures as evsti-
pliragms, for that nuitter. It is a fact, however, that intrazou'cial

354 CUMINGS AND GALLOWAY MORPHOLOGY OF TREPOSTOMATA

secretions are made much more freely and extensively in the Trepostomata
than in anv other order of Brvozoa. That the brown bodv itself should
become enveloped by a calcareous cyst is therefore rather to be expected.

In the Bryozoa universally the calcareous deposits of the ectocyst are
formed in the ectocyst, and not on it — that is, the whole zooecial wall,
whether calcareous or chitinous, is thoroughly permeated by the organic
matter of the ectocyst (see Milne-Edwards, 21; Nitsche, 26; Ostroumoff',
27; Harmer, 12; Calvet, 5, and Levinsen, 20). Hincks (14) states that
the ectocyst is a secretion of the endocyst, and this view has been defi-
nitely confirmed by Calvet (5). It is evident, therefore, that after the
endocyst has retreated from the zooecial wall it secretes a new ectocyst in
its new position. By this process the space occupied by the polypide is
restricted, and in the event of the foraiation of a complete cyst, as shown
in figures 2, 7, etcetera, it is ver}' severely restricted. It is this very
limitation of the space occupied by the polypide that constitutes, in our
view, the best argument that we are dealing here with a degenerated
individual.

Gregory has suggested that the cystiphragms are for the purpose of
strengthening the zocecial walls (11). The fact that these structures
ai-e commonly absent near the surface and at the growing tips of branches,
where such a function would be best subserved, is, we think, a sufficient
answer to Gregory's view. Ulrich (33), with a good deal of hesitation,
has suggested that the cystiphragms might represent ovicells. Their
great number (in some species) and irregularities of size and arrange-
ment and distribution, as well as their sporadic occurrence in many
species, are all against this view of their function. The fact that they
are invariably empty, that they never contain any foreign particles, would
also indicate that they were never in eoniimiiiication witli the exterior of
the colony nor with the body cavity. That their function is tlie re-
striction of space within the zooecial tube is, we believe, the natural con-
clusion from their appearance and relation to surrounding structures.

In functional zooecia — for example, in the surface layer of zooecia—
cystiphragms are often absent or restricted to the proximal portion of
the zooecia, indicating that these structures were probably developed
somewhat late in the life of the individual polypide. At the growing
ends of branches cystiphragms are seldom developed — that is, they are
usually absent from the axial region. It is likely that the budding off
of new zooecia goes on very rapidly in this region of the zoarium. Each
individual is short lived and never develops the characteristics of ma-
turity, much less of old age. When, as occasionally happens, the rate
of growtli in this part of the zoarium is checked, the individual zooecia

CYSTS AND CYSTIPHRAGMS 355

tliickeii tliL'ir walls, secrete diaphragms and cystipliragins (in species in
which the latter are a normal feature), and show all the various char-
acteristics of maturity. In other words, a mature zone is carried across
the tip of the branch. Such zones are often seen in longitudinal sections
of zoaria. Again, in erect ramose or frondescent zoaria, in which the
axes of individual zocecia lie in a more or less horizontal plane, the
cystiphragms are on the upper side of the zooecia. This fact probably
indicates that the endosarc tends to sag away from the zooccial wall in
response to the weight of the polypide and other zooocial contents.
Where the zooecia stand in a more nearly vertical direction, as in Praso-
pora, the cystiphragms are about equally developed on all sides of tlie
zooecium. A further argument in favor of the view that the cystiphragms
are concerned solely with the restriction of intrazooecial space, especially
in mature and senile stages of growth, is furnished by the peculiar relation
of cystiphragms to secondaiy deposits on the zooecial wall, as shown in
figure 17. Here the greatly thickened cystiphragms are seen to pass
directly into the secondary thickening (cingulum) of the wall, and in-
deed the cingulum of the distal portion of the zooecium figured consists
(luite evidently of thickened cystiphragms laid on flush — that is, without
any voids between them. This fact is shown at cy' in the figure. Sim-
ilar relations of the cingulum to cystiphragms are shown in figures 1, 6,
and 9. Lee (IS) suggests that the thickening of the walls in the mature
region is for the pui^pose of filling up the extra interzooecial space due to
the extension of the zooecial tubes radially outward from the axial region.
That it has this effect is obvious; but it is somewdiat doubtful whether
this is the primary reason for the thickening, and especially for the
secondary deposits so common in thick-walled species. This subject will
be furthof discussed under tlx' head of wall structure.

It is \\v\\ known tliat a'singlc zoo'cium may produce a succession of
polypides. each in iis turn dcgiuici at ing into a brown body. It has also
been ])oinlcd out hy l.c\iiiscii ( 1!») that the zoccciuni may be rcgiMiei-ated
/'// Idh). ('al\ct ( ■") ) holds. \\v hclicxc witli \ci'V good reason, thai these
successive degciici-alious ^A the polypide are eoiiiieeled wiih successive
ovulations. Such liguics as 1, "i. ;!, I, (!. !), K). and II \ci-v I'orclblv
suggest such a succession of reproductive efforts, witli a progressive re-
duction of the size and vigor ol the successive polypi(h's, reaching a cli-
max in the final extinction of the individual, with the sealing up of its
zooecial cavity ami the retained pro(lucts of the successivelv formed
brown bodies. 'I'lieic is ph-nty of analogy among recent Bryozoa for such
a life history. After the culmination of the process, we may suppose that

356 CUMINGS AND GALLOWAY MORPHOLOGY OP TREPOSTOMATA

a new zooecium budded out of tlie distal region of the old one in the
usual manner.

It is possible, following the suggestion of Levinseii, that the cysts are
due to the total regeneration of the zocecium; that we have here a zooe-
cium within a zorecium. There is not much, however, to support such a
view. It would be very difficult on such a supposition to account for the
appearances shown, for example, in figure 2.

Another possibility is that the cystiphragms are due to a double-walled
arrangement analogous to the hypostega of some recent Chilostomata.
The overlapping character of the cystiphragms and their evident produc-
tion in succession, together with their sporadic occurrence in many spe-
cies, do not favor this interpretation.

The cysts, with their inclosed brown masses, may be pathologic, due to
the entrance into the zooecium of deleterious foreign material or to para-
sitic bodies, and the consequent degeneration and death of the polypide.
This explanation would not be very different from the first explanation
given above. It Avould merely supply an exceptional rather than a nor-
mal cause for the degeneration of the polypide, and it would fit particu-
larly well those cases in which the occurrence of the cysts and brown
material is rare. It would hardly account for the regular occurrence of
such structures, for example, in Peronopora. In the experiments of
Harmer (13), mentioned above, the degeneration of a majority of the
polypides of a colony usually followed the introduction of the reagent
(Bismarck brown or indigo carmine) into the water in which the colonies
. were living.

The occurrence of these cysts and their accompanying brown masses is
not confined to material from any particular locality or horizon. We
have found the structures in specimens from all portions of the Ordo-
vician, from the Chazy up, and from all of the principal provinces in
which these rocks are exposed. The structures are therefore not due to
any local conditions, nor are they peculiar to any special time.

The cysts and brown masses are never found in the immature or axial
regions, nor even in the submature region of a zoarium. They are often
found in numbers just beneath an overgrowth. The indications are that
they are features of the fully mature portions of the zoarium. This adds
weight to the argument that they were produced in connection with de-
generating polypides.

Communication Pores

In his original description of Homotrypa curvata, Ulrich (29) men-
tions and figures "connecting foramina," passing through the inter-

COMMUNICATION PORES 357

zooccial walls. These were seen by him in tangential sections only. The
sli-iiitiires mentioned by Ulrieh have since been seen and liuurcil in sev-
eral species of Homotrypa by. Ulrieh (28), Bassler (1). and Cumings
and Galloway (10). We also discovered and figured connecting foramina
or, as we prefer to call them, communication pores in Batosfoma (9)
and have recorded their presence in many other genera (9). Our re-
searches of the past few years have shown that communication pores are
present in abundance in many, in fact most, of the genera of the Tro])-
ostomata. They may be most satisfactorily studied in Hetero[ri//i(i.
Del'ayia, Peronopora, and Bythopo7-a. Figures 23 tq 30 will, we think,
convince any one that the appearances are actually due to pores passing
directly through the interzooecial walls. Figures 23 to 27 show the pores
as seen in tangential sections; figure 28 as seen in a longitudinal section,
and figures 29 and 30 as seen in longitadinal sections cutting trans-
versely to the direction of the pores. Figures 27 and 30 are from a
specimen of Heteropora iortilis, from the Miocene of Peter.sburg, Vir-
ginia, kindly sent us by Doctor Bassler. Except that the communication
pores of Heteropora are usually more flaring at the mouth (double fun-
nel-shaped), there is no discoverable difference between them and the
communication pores of the Trepostomata. The figures are drawn. with
absolute fidelity to the original sections. In ])oth cases the lamina of
the walls appear to be cut squarely off at the pores. This suggests the
possibility that the pores may have been formed by resorption.

The appearance just mentioned caused us for a time to entertain the
possibility that the pores might- be perforations made by some sort of
parasite, possibly an alga or fungus. Perforation of calcareous tests by
such means is not an uncommon thing. Against this possibility, how-
ever, is the regularity and universality of occurrence of the communica-
tion pores, the fact that they pass straight through the walls, usually in
llic thinnest place. Ihcir iiiiir<niii diameter and ap])earanee, and, more
ihan anylhin.i;- else, ihc idcnlily of appcai'ance of the ]n>rr> in ihc Tre])-
osloniata and in 11 rlcrD/inni. It the hitter genus they arc ibdlnitcly
known 1(1 1)1' i-iiMiin iinicat imi |mm'cs.

We have found these communication pores in greater or less abundance
and perfecti<tn in II cicrotrypa. J)fl-ai/!n. TTomotrypa, TTallopora, Am-
plexopora, Bylliopora. Eridolrypa. //omulrypella, Peronopora. Sfigiiia-
lella, BalofiloDia. Rliomholrii/ia. etcetera. It is likely that they were
universally ])rescnt in tlic Trepostomata. Similar structures have been
seen in Cceloclema, CeramoporeUa. etcetera; but the typical Heteropora-
like pore is developed only in the Trepostomata.

;!.")s cumings and galloway morphology of trepostomata

Intrazo(ecial Spines

In a new species of Nicholsonella, N. cornula. Doctor Galloway dis-

co\ered excessivel}^ minute, apparently hollow, spines projecting into the

zooecial cavity. These are represented in figures 33 to 39, inclusive. The

sphies are found only in the submature region, nearly always on the lower

side of the zooecium and always curving do^vn toward the axial region.

Tlie various appearances presented Ijy these spines are illustj-ateil in 1he

figures. Figures 32, 34, and 36 show their appearance unde "."" ,

objective (X 65), and figures 33, 35, 37, and 38 under a 4 nv , ■^

(X 387). The spine usually has the appearance seen in fi

end of the spine being bulbous and the wall appearing dou

the spine were hollow and continuous with the thin liniii • -, ,

zooecium. Some of the spines in this species, however, f i ,

^ . I ? ' ,| or to para-

spines in a nearly related species have the appearance re^t-i, i .^v]p

and (/. figure 33, and n and m, figure 32 — that is, the sp ^ -, " ,•

and appears solid. Either it is solid or the wall is so thii^.i

'^ . . . than a nor-

resolved by the very high magnification used. Most of the , ni . •
hollow, and such examples as are .shown in figure 38 coul i h o u
interpreted in any other way, for they not only appear ho^^^^^^j^^g ^^
tain small particles of foreign matter, and moreover appear -^ • , <;
cate with pores in the wall (x in the figures). Some of th-, ■, <■ ii
tain a dark spot, resembling an air bubble, and it may veryL rpfio-PTit
these are actually bubbles (see figure 33, n). It is possible tli, poionie-
was originally solid, and that it 1:)ecame overlain by a seconds .
If the original spine, acting as the core, were perfectly transpu .^ •
appearances would be exactly the same as though the spine were origin..rp.
hollow.

What possible function these spines could have had we do not ventu
to say. The nearest analogy among recent Bryozoa is found in the spin^
figured and described by Nicholson in Ileteropora neozelanica (24). T
deed, the resemblance between his figures and our figure 32 is remarkably
strong. We have not been able to obtain any specimens of Heteropora
neozelanica. It is possible that the resemblances mentioned are without
significance, but they are interesting enough to warrant further study,
which we propose to give them nt our earliest opportunity.

Wall Structure

integrata and amalgamata

The general characteristics of the wall structure of the Trepostomata
have been kno^wn ever since the classic work of Nicholson (22-25). We

WALL STRUCTURE 359

believe that wall structure, properly understood, will prove important in
generic and family classification within this order. This idea was empha-
sized by Ciimino-s in his paper on the Heterotrypidse (6). In their re-
vision of the Trepostomata, Ulrich and Bassler (35), on the basis of wall
structure, divided the order into two divisions: the Amalgamate, in
which "the boundaries of adjacent zotpcia are obscured by the more or
less complete amalgamation of their walls,'' and the Integrata, in which
"the bouiidf!,rieR of adjoining zocecia are sbai'plv defined by a well-marked,
ostomaict. ] divisioiinl lino" (34).
Deliayia, 1
convince an fsroLOor of the walls and the median line

direct y iroi aiTfu^^gejYigi-i^; ^f the Trepostomata seemed to the writers to
as seen m :^^^ ^^^^ ^^^^^^ iiseful. The first to express any dissatisfac-
an( gur < -^ (18), who noted that a dark line was occasionally
\eise y o jgQJgg otherwise referable to the Amalgamata. Our atten-

PL O

specime \)een called to this same fact in certain species of Hetero-

gmia, -mc } |.yp j^g^j member of the Amalgamata. It presently occurred
1'*^'^ a careful restudy of the histology of the trepostome walls

ne - P / ' ligher magnification than has hitherto been employed and
„ \\ rather than in tangential sections, since the actual course
'^^^ 'iminas from face to face of the wall can not be folloAved in

f"^d of section. The results of these studies are shown in fig-
^ ' •' , inclusive. Figure 45 shows the median line in its sharpest

/^.ppears in Batostoma vnnchelli, while figures 42, 48, and 50
^ . typical amalgamate structure as it appears in Bythopora,
^ ^v,ypa, and Dekayia. These two types of structure certainly ap-
pear to be very distinct; nevertheless both may and do occur in the same
species, and indeed in a single specimen. Figures 46 and 47 are sections
of Heterotrypa prcenuntia, both from the mature region. Figure 43
shows the amalgamate phase of structure in Amplexopora septosa mul-
iispinosa, a member of the Integrata, while figure 48 shows it in Hetero-
trypa proUfica, a typical member of the Amalgamata. There is no real
difference between these two walls. It is very rarely indeed that the ap-
parently sharp divisional line of the wall is not resolved by high magnifi-
cation into an irregular zone, such as is shown in various phases in figures
43, 49, and 5(;. Figure 40 is instructive, since Eridolrypa is regarded as
a member of the .\malgamata. It may with profit be compared with
figure 45. Tlic ivw meaning of this dark zone is revealed by comparison
of figures 56 and 'u. These sections are cut in portions of zoaria where
*he zoarial surface has been perfectly preserved by overgrowth. The
^TOwing edge of the wall is shown intact. In figure 56 {Hallopora

^ XXVI — Bull. Geol. Soc. Am., Vol. 26, 1914

360 CUMIKGS AND GALLOWAY ^EORPPIOLOGY OF TREPOSTOMATA

sphndens) , a member of the Integrata, the grov/ing edge of the wall is
very thin, and the wall becomes gradually thicker farther in, finally re-
ceiving a secondary deposit, the cingulum. Because of this method of
growth the laminte of the wall have a very steep pitch, and the bend they
make in tlie axis of the wall is sharp. On the other hand, the growing
edge of the wall in Dckayia (figure r)!) is smoothly rounded, and the
laminae pass across from zooecium to zoct'cium Avitli a regular curve. For
some reason, wlicrever the wall laminre of tlie trepostomes are sharply
beiit the material appears dark. Tliis is true also of sharp bends of dia-
phragms (figures 1, 9, 11, 44, 45, 4G, 47). It is probable that the size
and arrangement of the minute graiiules of wliicli the wall laminte are
composed differ slightly at such points fTom the normal size and ar-
rangement in other parts of the wall. In fact, in well preserved material
and in very thin sections it can he shown that this is actually the case.
Usually the granules are too small to show under the magnifications in-
dicated in these figures. In some species, as in Bytliopora gracilis,
Heterotrypa prolifica, etcetera, the granules can l)e distinctly seen under
a 4 mm. objective and 10 X ocular. Figure 42 shows very clearly their
appearance in Bythopora. In the latter genus, and in the Amalgamata
generally, these larger granules are distributed in more or less concentric
bands from face to face of tlio wall, or they are distributed in a broad
zone in the central portion of tlie ^\i\\\. In the Integrata commonly, and
occasionally in the Amalgamata. tliey are more closely concentrated in
the axial region of the wall, and when bands of granules from either side
of the wall are present they are often offset instead of continuing unin-
terruptedly across the median region of the wall. Such an arrangement
can be seen in figures 44 and r)(i. The granules of the lighter appearing
portions of the walls are so minute tliat they can scarcely be seen under
any feasible magnification. It may l)e remarked that these minute gran-
ules of the trepostome wall probably represent each an individual cell of
the original ectosarc, since we have good reason to believe that the cal-
careous deposits of the zooecial walls of Bryozoa are made intracellularly.
There is no good evidence that either type of wall described above was
double except in the sense that any Ijryozoan wall is double, namely, be-
cause it is secreted bv the juxtaposed or coalesced ectosarcs of two ad-
joining in(li\i(liials. Xor does the analogy of the Cyclostomata, tlie order
nearest related to the Trepostomata, lead us to expect a double wall in
the latter order. To say that the boundary between adjoining zooecia is
obscured in the Amalgamata does not go far enough. There is no such
boundary. The wall was one and single and common to two zocecia, as
it is in the Cyclostomata (Levinsen, 20). On the other hand, such ap-

WALL STRUCTURE o61

pearances as are shown in figure 4:~) might perfectly well be interpreted
as indicating a dniible wall, were it not for the fact that this pliase and
the phase shoM'n in figure 43 may and do occur in tlie same specimen.

In the recent Chilostomata, according to Calvet, Levinsen, and others,
sonic gciici'a lia\c a double and some a single wall, and tlu>re is no impor-
tant classiticatory \alue to this difference. If the differences above de-
scribed are due primarily to the steepness of pitch of the wall laminas, it
is liT\cly that the classificatory value of this phase of wall structure in the
Treposfomata is also of subordinate rank. The calcareous lamina^ are
laid down in the growing edge of the wall j)arall('l to the two surfaces of
the amalgamated ectosarc, as shown in figui'cs 50 ajid 57. If the wall is
knife-edged, as shown in figure 56, the laminae will pitch very steeply
and there will be a sharply defined central zone. If the growing edge of
the wall is blunt, as shown in figure 57, there will be no definite median
boundary. Phases intermediate between these two extremes will also he
of common occurrence.

It has often been asserted that the duplex character of trepostome
walls is proven by the tendency of the walls to split down the middle.
If this were a fact, it would unquestionably be a good argument; Init it
is not a fact, ^^'e have examined thousands of fractures, under high
magnifications, and have found that the split invariably folloAvs the direc-
tion of the laminffi, crossing back and forth across the median region of
file wall with perfect indifference. AVhere the lamina? are very steep, the
wall often appears under low magnification to l)e split accurately in the
middle; but a closer examination will always show that it is not. In the
axial region, where the lamintu are parallel with the surface of tln' wall
(figiu'e 58. a.i'). tlie split may follow the median line, or any other line
parallel with it, often for a considerable distance. The highest obtain-
able magnification (oil immersion) has failed to reveal any indication of
duplex structure of th<' walls in the axial icgion of the zoarium. The
whole wall iimler such magnification appears merely as parallel chains
of granules. Figure 58 shows the wall of HiujindleUa spinosa where it
emerges from the axial region. Op])osite a.r there appears to be a dark
di\idiiig line, but fai'tliei' in toward the axial region this entirely disap-
pears. Farther out toward the mature region the dark median /.one be-
comes interrupted and tlie lamimi! bend more or less smoothly over the
axial region of the wall. The mature region of the wall of this genus is
like that of JJehai/ia, figure 50.

THE OINGVLUM

'r\\{: walls of thr Trrpostomata often show a greater or less amount of
secondary thickrnini;-. These secondary deposits we have designated the

362 CUMINGS AND GALLOWAY MORPHOLOGY OF TREPOSTOMATA

cingulum (9), because in tangential sections (figures 23 to 36) they give
the appearance of a well defined ring or zone of deposits adjacent to the
zooecial cavity. The cingulum is shown in longitudinal section in figures
43, 44, 46, 47, 56, and 58. In figures 45 and 48 there are also massive
secondary deposits, which do not, however, form so sharply defined a layer
as is shown in the other sections. Tliese secondary deposits are inti-
iiuiiclv rchitcd lo |lic (li;ii>liragnis. as llie figures clearly show. The dia-
phragms and the ciiignhnti nrc coiil Iiiikmis (figures 44, 46, 47, and 45).
Ft appears, fliprefore, that the secretion of ;i diapfiragm is coincident with
the formation of a deposit over tlie entire inner surface of the zooecium.
The extremes to which this secondai-y tliickening may go are illustrated
in figures 1, 9, 11, 17, 45, and 47. An unusually extreme example is
Diplotrypa hicornis, figured by Bassler in his volume on the Baltic
Bryozoa (4).

The fact has already been pointed out that the cystiphragms may be
very closely related to this secondary thickening of the walls. This is
beautifully illustrated in figure 17. Thick-walled species with cysti-
phragms (for example, HomotrypeUn) afford numerous illustrations of
the same thing. In figure 17 the boundary between the primitive wall
and the secondary deposit is clearly shown by a distinct line, and the
thickened cystiphragms have the same definite relation to the cingulum
as do the diaphragms in the cases already cited.

The thickening of the interzooocial walls, due to the development of
the cingulum, is often very great — far greater than would merely com-
pensate for the increasing separation of the zocecia, as they extend radially
outward from the axial region. There is an actual reduction of the size
of the zooecial chamber; indeed, in some cases, an extreme reduction
(figures 1 and 17). We believe that this extreme development of sec-
ondary deposits is a senile feature, analogous to the great thickening of
brachiopod shells and the shells of the Mollusca in old age. In recent
Bryozoa the zooecia of the older portions of zoaria often become almost
or quite filled up with stony deposits, and it seems that the ectosarc may
continue to secrete such deposits after the polypide has wholly disap-
peared from the zooecium.

We can not dismiss this subject without calling attention to the striking
resemblance between the wall structure of the Trepostomata and of the
Brachiopoda. In such sections as are shown in figures 45 and 49 it
amounts almost to identity. In figure 54 also the fascicles of wall laminae
look almost precisely like the similar fascicles of lamina? so often seen
in sections of brachiopod shells.

FUNCTION OF ACANTHOPORES 363

ACANTHOPORES

The function of acanthopores has long been a puzzle. It has been
surmised that these hollow, thick-walled tubules were in the living colony
surmounted at the surface by some sort of spine, aviculariuni or vibrac-
ulum. Waagen and Wentzel (36) made the mistake of supposing that
they were young zowcia (corallites) . Several years ago we noticed among
our sections of Del-ayia niaculata a few examples of overgrowths in which
the entire spine, extending well above the surface of the zoarium, is
preserved. Two of these sections are figured herewith (figures 51 and
52). In figure 51 every detail of the overgrowth, calcite structure and
all, has been delineated, in order to eliminate, so far as possible, the
personal interpretations of the authors. The drawing is photographically
exact. The appearance at t, which might almost be interpreted as an
avicularium, has probably been produced by the crushing of the end of
the spine. The spine shown in figure 53 extended up into a mass of
sediment that had coated the zoarium and had subsequently been covered
by the overgrowth. It seems to be perfectly intact. The actual diameter
of these spines is about that of a human hair and they extend about 21/^
zooecial diameters above the zoarium. Most acanthopores, however, were
much smaller than these. In Del-aijia the exsert portion of the spine
was brittle, as shown by the fact that in overgrowths of specimens of
(his genus quantities of shaiply broken fragments of spines are often
seen. A bent spine is a rare occurrence. There is some evidence, how-
ever, that in certain other genera the spines were flexible (10). The
laminffi of which the spine is composed run parallel with the axis of the
spine. Their appearance under high magnification is shown in figure
53. This drawing is from the region s of the preceding figures. Figure
51 shows the region s' of a spine highly magnified. This part of the
spine has been buttressed by extensive secondary deposits laid on it by
the adjoining zooecia. The primary wall of the spine can be distinguished
in the inner fascicle of laminae next to the lumen. In figure 51 this pri-
mary spine can bo traced far down into the zoarium. It is obvious that
as the zocecia grow distally they submerge the exsert portion of the spine,
whicli latter keeps lengthening. If the axis of the spine is not perfectly
parallel with the axes of the surrounding zofBcia, the submerged portion
of the acanthopore will trend more or less diagonally between adjoining
zooecial walls. This explains an appearance very often seen in longi-
tudinal sections of species that have large and well defined acanthopores.

The protective function of such spines can scarcely be doubted. Their
very number and relation to the zorecial apertures indicate sucli a function

:)G4 CUMINGS and galloway MORPHOLOGY OF TREPOSTOMATA

beyond question. In addition, we have occasionally seen a whole battery
of spines of unnsually large size surrounding the hole of a parasitic
boring worm that had penetrated the zoarium. There are, however,
many different kinds of acanthopores, and it is not likely that they all
had the same function. The type described abo\e is common in the
Heterotrypidffi, in some species of Tloinotrypa, in HoniotnjpeUa, Perono-
pora, etcetera. On the other hand, the minute acanthopores with ill-
defined lumen, so often seen in Homotrypa and other genera, may have
supported an exsert process of a very different sort.

Merlia Normani Kirkpatrick

After the senior author's paper on the development of the Monticu-
liporoids (8) was distributed, Dr. W. D. Lang, of the British Museum,
called our attention to several notes that had been published in Nature
and the Proceedings of the Eoyal Society by Doctor Kirkpatrick, of the
Museum, in regard to a peculiar recent sponge, having an auxiliary skele-
ton, externally greatly resembling the zoaria of certain Monticuliporoids
(16, 17). Doctor Kirkpatrick in these announcements states without
hesitation that, on the basis of the resemblances mentioned, Monticulipora
should be regarded as a sponge. In his elaborate paper on the morphol-
ogy of Media, Doctor Kirkpatrick (15) had taken a much more conserva-
tive view of the resemblances.

Through the kindness of Doctor Lang and Doctor Kirkpatrick we
were able to obtain several specimens of Merlia, preserved in alcohol.
We have sectioned these and made a very careful study of the wall
structure, which is shown in tangential section in figure 41. A glance
will convince any one that there is not the slightest resemblance between
this structure and anything ever seen in the Trepostomata. In Media
the calcification evidently proceeds by spiculation from definite centers
{c, c). At the growing edges of colonies of Media the skeletal ele-
ments have not yet coalesced, and one sees here nothing but chains of
small erect pillars distinctly separated from each other. In later growth
these coalesce by the radial extension of their spicules or fibers. In
longitudinal sections of the walls these fibers are seen to arise vertically
from the substratum and turn ouUvard, like the straws in a sheaf of
wheat. This explains the appearance shown in the tangential section.
The central granular-appearing nucleus is where tlie fibers are cut trans-
versely, and the zone of radiating fibers surrounding the nucleus is where
the outward-turning fibers are cut more and more longitudinally. The
boundaries between adjacent sheaves of spicules are very sharp. The

SUMMARY AND CONCLUSIONS 365

structure shown in figure 41 may with profit be contrasted wilh llic
typical trepostonie structure shown in figure 38 of the same ])late or in
figures 23 to 37. Agaiii in longitudinal sections of Merlin the cross-
partitions (diaphragms) have a large central perforation with a down-
ward-turning collar — iinlikr anything e^^cr noted in the t ii'puslomes.
The fact is that the structure of Merlia is about as different from that of
the trepostomes as anything could well be. Kirkpatricl< was completely
mislead by superficial resemblances.

SUMMAKY AND CONCLUSIONS

This paper deals with a number of morphological and hislological
characters of the Trepostomata which are either new or have hcix-tofore
been imperfectly understood.

Cysts and cystiphragins. — More or less perfectly formed calcareous
cysts inclosing peculiar brown material are described and their relation
to cystiphragins explained. It is suggested that these structures are
developed in connection with successive degenerations and regenerations
of the polypides, and that the purpose of cystiphragms is the restriction
of intrazooecial space.

Communication pores. — The histology of communication pores in the
Trepostomata and in the genus Heteropora is described, and it is shown
that not only are these structures probably universally present in the
Trepostomata, but that the pores have the same characteristics and ar-
rangement as in Heteropora. >

hitrazocecial spines. — Certain extraordinary spines projecting into the
submature region of zooecia of a species of Nicholsonella are described
and their resemblance to the spines of Heteropora neozelanica, as figured
by Nicholson, is pointed out.

\Yall structure. — The structure and histology of the walls of the
Trepostomata, as seen in longitudinal sections, is minutely described. It
is shown that the (ii\isions Integrata and Amalgamata, hascd on ihc
supposed presence or absence of a definite divisional plane in the center
of the wall, are o])eii to some question, and that the trepostonie wall was
probably single and cominoii to adjoining zooecia, as it is in the Cyclo-
stomata. The method of oi'igin and the varying arrangements of the
wall lamina' are descrihcil. aiid it is shown that the presence or absence
of a dai'k median line in the wall ile]K'nds to a large extent on Uie steep-
ness of pitch of (he lamina', which in turn depends on whether the grow-
ing edge of the wall is thin and sharp or blunt and smoothly rounded.
It is shown thai the .secondary deposits (or cingulum) are delinilelv re-

366 CUMINGS AND GALLOWAY MORPHOLOGY OF TREPOSTOMATA

lated to the diaphragms, and in some cases to the cystiphragms, and that
these massive deposits are probably best interpreted as senile characters.

Acanthopores. — It is shown that in Dekayia the surface of the colony
was characterized by minute hollow spines, about the diameter of a hair
and extending two or three zocecial diameters above the surface. The
acanthopores are merely the submerged portions of these spines. The
function of the spines was undoubtedly protective.

Media normani Kirkpatrick. — It is demonstrated by a study of wall
structure that Merita has no relation whatever to the Trepostomata.

BlBLIOGRAPTIY

1. R. S. Bassueb: The structural features of the Bryozoau genus Homotrypa,

with descriptions of species from the Cincinnatian group. Proceedings
of the U. S. National Museum, volume xxvi, Washington, 1903, pp.
565-591.

2. : A study of the James types of Ordoviciau and Silurian Bryozoa.

Proceedings of the U. S. National Museum, volume xxx, Washington,
1906, pp. 1-66.

3. : The Bryozoan fauna of the Rochester shale. Bulletin 292, U. S.

Geological Survey, Washington, 1906.

4. : The early Paleozoic Bryozoa of the Baltic provinces. Bulletin 77.

United States National Museum, Washington, 1911.

5. Louis Calvet: Contribution a I'Histoire Naturelle des Bryozoaires Ecto-

proctes marin. Trav. Inst. Zool. Monti>ellier. N. S., memoire 8, Mont-
pellier, 1900.

6. E. R. CuMiNGS : A revision of the Bryozoan genera Dekayia, Dekayella and

Heterotrypa. American Geologist, volume xxix, Minneapolis, 1902, pp.
197-217.

7. : The stratigraphy and paleontology of the Cincinnati series of In-
diana. Thirty-second Annual Iteport of the Department of Geology and
Natural Resources of Indiana, Indianapolis, 1908, ])p. 607-1189.

8. : Development and systematic position of the Monticuliporoids. Bul-
letin of the Geological Society of America, volume xxiii, Washington,
1912, pp. .357-370.

9- and J. .J. Galloway: A note on the Batostomas of the Richmond

series. I'roceedings of the Indiana Academy of Science for 1911. In-
dianapolis, 1912, pp. 147-160.

10. : The stratigraphy and paleontology of the Tanner's Creek sec-
tion of the Cincinnati series of Indiana. Thirty-seventh Annual Report
of the Department of Geology and Natural Resources of Indiana. In-
dianapolis. 191.3, pp. 353^78.

11. J. W. Gkegouy : Catalogue of the fossil Bryozoa in the Department of
Geologj- of the British Museum (Natural History). The Cretaceous
Bryozoa. London, 2 volumes, 1899, 1909.

BIBLIOGRAPHY 367

11*. S. 1". IIakmer: a revision of the genus Steganoporella. Quarterly Journal
of Microscopical Science (N. S.), volume xliii, part 2, London, 1900, pp.
225-297.

13. : On the nature of excretory processes in marine Polyzoa. Quarterly

Journal of Microscopical Science, volume xxxiii, London, 1892.

14. Thomas Hincks : A history of the British marine Tolyzoa. Two volumes,

London, 1880.

15. R. Kirkpatbick: Merlia normaui, a sponge with a siliceous and calcareous

skeleton. Quarterly Journal of Microscopical Science, series 2, volume
Ivi, London, 1911, pp. G57-702.

IG. : Merlia normani and its relation to certain Paleozoic fossils. Nature,

volume Ixxxix, Ixmdon, July, 1912, pp. 502-503.

17. : Note on Merlia normani and the "Monticuliporas." Proceedings of

the Royal Society, volume 85, Loudon, 1912, pp. 5G2-5(J3.

18. G. W. Lee: The British Carboniferous Trepostomata. Memoirs of the

Geological Survey of Great Britain, Paleontology, volume i, part 3, Lon-
don, 1912, pp. 185-195.

19. G. M. R. LE\^NSEN : Sur la regeneration totale des Bryozoaires. Oversigt

over det Kgl. Danske Mdenskabernes Selskabs forhandlinger, number 4,
Christiania, 1907, pp. 151-159.

20. : Morphological and systematic studies on the Cheilostomatous Bry-

ozoa, Copenhagen, 1909.

21. Henri Milne-Edwarus : Quoted by G. R. Simpson, hi A Handbook of the

genera of North American Paleozoic Bryozoa. Fourteenth Annual Re-
port of the State Geologist of New York. Albany, 1895, pp. 407-GG7.

22. H. A. Nicholson: On the structure and affinities of the Tabulate Corals

of the Paleozoic Period, with critical descriptions of Illustrative species,
Edinburgh, 1879.

2.3:. : On the minute structure of the recent Hctcropora ncozelanica, r>iisk.

and on the relations of the genus Heteropora to Monticulipora. Annuls
and Magazine of Natural History, volume vi, 1880, i)p. .329-338.

24. : On the structure and affinities of the genus Monticulipora and its

subgenera, with critical descriptions of illustrative species, Edinburgli.
1881.

25. and R. Lydekker : Manual of Paleontology, Edinburgh and London.

1889, chapter on the Monticuliporoids. pp. 34G-357.

20. HiNKiCH, Nitche: Beitnige zur Kentniss der Bryozoeu. III. Ueber <lio
Anatomie und Entwickelungsgeschichte von Flustra membi'anacea
Zeitschrift fiir Wissenschaftliche Zoologio. xxi, Leipzig, 1871. pp. 37 !»1

27. A. Ostroumoff: Reniarques relatives anx recherches de M. Vigelius sui

les Bryozoaires. Zoologisclier Anzcigei-, viii. Leipzig. 188G, pp. 290-2!tl

28. K. (). Ulrich : American Paleozoic Bryozoa. Journal of the Cincinnat

Society of Natural History, volunics v to vii, Cincinnati, 1882-1884
v(»lume V, pp. 121-175, 2.32-257; volume vi, pp. 82-92, 148-168, 245-279;
volume vii, pii. 24 51.

29. : American rnleo/.oic Bryozoa (see above), volume v, ji. 242. 1882.

30. : ,\merican l'alof>zoic Bryozoa (see above), volume vi, p. 82. 1883.

368 CUMINGS AND GALLOWAY MORPHOLOGY OF TREPOSTOMATA

31. B. O. Uleich : Paleozoic Bryozoa. Geological Survey of Illinois, volimic

viii, Springfielfl. 1S90, pp. 285-688.

32. — — : On Lower Silurian Bryozoa of Minnesota. Geology of Minnesota.

volume iii. part 3 of Final Report, Paleontology, Minneapolis, 1895, pp.
96-332.

33. — — : Text-book of Paleontology, by Karl A. von Zittel, translated and

edited by Charles K. Eastman, London and New York, 1900, pp. 271-27S.

34. - — -: Idoii, second edition, 1913, pp. 330-3.39, revised and extended by

R. S. Bassler.

35. and R. S. Bassler: A revision of the Paleozoic Bryozoa, Part II,

Trepostomata. Smithsonian Miscellaneous Collections, volume 47, Wash-
ington, 1904, pp. 15-55.

.'!(!. William Waagen and Joseph Wenzel : Salt Range Fossils. Ccelenterata,
Memoirs of the Geological Survey of India. Paleonlologica Indica,
Series xiii, Calcutta, 1886.

BULL. GEOL. SOC. AM.

VOL. 26, 1914, PL. 10

MORPHOLOGY OF THE TREPOSTOMATA

explanation of plates 369

Explanation op Plates

Pl^\TE 10. AIORPHOLOGY OF THE TrEPOSTOMATA.

Figures 1-7 and 9. — Longitudinal sections of Beterotrypa suhra^mosa Ulrich.

The cysts aiul their iiu-loserl hrowii masses (ft) are shown lii
those fisuivs. The proxiiii.-il :uul distal diaphraguis are lettered
</' and (I respcclively. and the neck of the cysts )(7.". The distal
diaphragm is ott(>n greatly thickened, while the zooecium of which
it forms the hasal wall has an unusually thick cingulum (fignre>^
1 and r»). All figures X 05. (128^16, 11, 5, 5, 4, 4, 4, 14.)

Figures S and 10. — Longitudinal sections of three zooeeia of Batostoma
variabile.

Significance of letters the same as in preceding figures. In the
right-hand zocecium of figure 8 the neck of the cyst is very nar-
row and straight, and its connection with the lower part of the
cyst has heen ohliterated Figure 10 shows two successive sets of
cystiphragms and brown bodies (b and 6'). X 65. (126-6 ; 94-10.)

370 CU MINGS AND GALLOWAY MORPHOLOGY OF TREPOSTOMATA

Plate 11. — Morphology of the Trepostomata.

Figure 11. — Longitudinal section of a zocccium of Heterotnjpa subrawosa
JJlrich.

In this example tlio oyst is stoppered by a very thick diaphragm.
X 65. (123-19.)

Figure 12. — Longitudinal section of Monticulipora epidermata V. (ind B.

As in most of the Monticuliporida?, sensu strictu, the brown
mass is not enveloped by ;i fully formed cyst, but is more or less
isolated by the cystiphra.^ms and the proximal diaphragm. X 65.
(50-23.)

Figure 13. — Longitudinal section of xitactopora intermedia C. and G.

The brown material is present in all three zocecia, and there is
a well defined cyst in the one to the right. X 65. (157-23.)

Figure 14. — Longitudinal section of several zooecia of Amplexopora pustulosa.

The well defined cyst and brown mass have the same form as in
Heterotrypa. X 65. (125-1.)

Figure 15. — Longitudinal section of Honiotnjpa cf. subramosa.

The arrangement of brown material and cystiphragms is the
same as in Monticulipora. X 65. (186-9.)

Figure 1(].— Longitudinal section of Homotrypella rotundipora n. sp.

A well defined neck is formed by the cystiphragm on the right-
hand wall. X 65. (148-13.)

Figure IT. — Longitudinal section of Homotrypa spissa n. sp.

This section shows a well defined brown mass and an unusual
thickening of the cystiphragms icy), which are intimately related
to the cingulum. X 65. (202-18.)

Figure 18. — Longitudinal section of Feronopora vera.

A very sharply defined brown mass and inclosing cystiphragms.
X 65. (112-12.)

Figure 19. — Longitudinal section of Prasoporu siniulatrix.

Here the polypide chamber, in which is lodged the brown mass,
is very greatly restricted in size, and the nock of the cyst is small
and well defined. The distal and proximal diaphragms are also
clearly defined. X 65. H1 1-10.)

FiGUKE 20. — Longitudinal section of Feronopora vera.

Two very typical brown masses with their accompanying cysti-
phragms are shown (h and 1)'). X 65. (112-12.)

BULL. GEOL. SOC. AM
//

VOL. 26, 1914, PL. 11

MORPHOLOGY OF THE TREPOSTOMATA

XXVII I'.i 1,1.. (;i.,ii.. Sell'. Am., Ndi,. I'c,, I'.iM

BULL. GEOL. SOC. AM.
.21

VOL. 26, 1914, PL. 12

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MORPHOLOGY OF THE TREPOSTOMATA

EXPLANATION OF I'LATES 371

I'LATE 12. MoiirilOLOGV UF THE TBEroSTUM ATA.

Figure 21. — I'drlhilhi (lifnirdnniKilii- (Irairiiif/ of a IdnniltidiiKil siflioii o/' u
zooccium of Pniftoiiora Hiiiiilatrix.

This is ail extromely well dofinefl brown mass with tlie cysti-
phragiiis dovelopc'd all aroinul the zoocciuui, as is usually the case
in Prasopoi-a. X 05. (11 i-1 G. )

Figure 22. — Sciiii-diiif/rdiiniKilic druiriini of u Joiii/il (hUikiI scdioii of <t zou-ritiui
of Pcioiiopora vera.

This shows tho characlcristic succession of hrowii masses and
eystiphragms of this species. X 05. (112-12.)

Figures 2o to 2(>. — 'I'uitijtiiiiul sections of Ilclciolrnpd uinl f'croiioiioia (li-iirc

24).

The normal appoaraucc of comiiniuicatioii iior(>s is shown in
these sections (^0- I'l'e wall lamin;p are cut squarely off at the
pores. X 287. (in,S-21 ; 147-14; 101-20; 20.)

Figure 27. — Tan;/( hCkiI section of Ileteropora torlilis from llic Miocene of

Petershttrn. Vti.

The coiiimunicatiou pores, excei>t for the flaring nmudis. pre-
sent exact l.v the same appearance as in the Treposlomata. That
the douhle-funnel shape is not invariable is sliowii by the pores p
and ?>'. X-2S7. (118-18.)

Figure 28. — Longitudinal section of tlie icall of Heteroin/iKi proli/icd.

The pore presents the same appearance as in the tangential
section. X 287. (168-21.)

Figure 29. — Longitudinal section of the tcall of Heterotnjpa prolipca.

This section cuts through the wall in such a way as to cross the
pore in a direction somewhat oblique to the axis of the pore.
X 287. (108-21.)

Figure oO. — Portion of n louf/il iidinal scclian of tlir irall of (felrropord toil it is.

'IMie wall is cut in the same manner as the wall of IIeleroii-ypa
of the picccdig ligure. Some of the jiores are cut straight across
and some more or less obliquely. The appearances are exactly the
same as in figure 20. X 287. (118-18.)

Figure ul, — A fcic grains of the brown ntutcriul of a cgst of llelerotrgpu .siil)-
ramosa.

The grains have the form of minute concretions or nodqles,
X450. (123-4.)

372 COMINGS AND GALLOWAY MORPHOLOGY OF TREPOSTOMATA

Plate 13. — Morphology of the Trepostomata.

Figures 32 to 39. — Sections of NicJioIsoncUa coruuJa n. sp.. skoicinri the minute
spines projcctino into the zocccia.

The usual appearance of the spines is shown in figures 35 and 37.
In figure 33 are shown spines that are either excessively thin-
walled or solid. At n in this figure and in the adjacent spine arc
seen black bodies that may be bubbles. The appearance shown at
m is probably due to the double refraction of the calcite. Figure
38 shows unusually thick-walled spines and possibly excavations
(.T, .t') in the walls of the zocecium, opposite the lumens of the
siiines. The spines m and n appear to contain foreign particles.
The thin transparent lining of the zoopcium is continuous with the
walls of the spines. This feature is also shown in figure 'M.
Figure 39 shows the i-egion of the zoarinm in wliich the spines are
invariably found, together with the fact that they are usually on
the lower sides of the zooecia. Figiires 34 and 35 show the same
set of spines under different magnifications. This is also the case
with figures 36 and 37. Figures 32, 34, and 36, X 65. Figures 33,
35, 37, and 38, X 287. Figures 39, X 25. (150-5, 5; 175-6, G;
150-5, 5; 175-23; 175-6.)

FiGUKE 40. — Longitudinal section of Heterotrypa pi'olifica.

This figure shows four zooecia emerging at the surface of the
colony, with their walls completely intact and their proximal dia-
phragms all developed at the same level. The distance from the
diaphragm d to the distal edge of the wall represents the length
of a typical zocecium. In the zocecium z is shown the thickening
of the walls often seen in the neck region of the zocecium. In
species with cystiphragms. there is often a circlet of cystiphragms
at this level. X 65. (102-13.)

Figure 41. — Tangential section of Mcrlia normani Kirkpatriclc.

The sheaves of fibers or spicules that make up the wall of this
sponge, with the sharp lines of demarkation between adjoining
sheaves, are clearly shown, x 65.

BULL. GEOL. SOC. AM.

VOL. 26, 1014, PL. 13

ft. iM:

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■^:r

'K^

MORPHOLOGY OF THE TBEPOSTOMATA

BULL. GEOL. SOC. AM.

42 mi>',

VOL. 26, 1914, PL. 11

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m:^H

MORPHOLOGY OF THE TREPOSTOMATA

EXPLANATION OF PLATES 373

rj,ATE 14. MOKI'IIOLOGY OF THK TREPOSTOM ATA.

l'"iiiURE 41'. — Loin/iliKlinal section of a poiiion of the tvaH nf lijillioitora (/rueilis.
Mature resioii nenr the surface of the zoariuiu. The granular
appearance of the dark hands and 1h(> ahsence of any suggestion
of a dujilex wall are distinctly indicated. X 287. (L"i9-7. )

Figure 43. — LonnitiidiiKil xrctiou in the tnatnre refiion of Aiitple.rnpora mutti-
spiHoxu var.

This section shows the cingulum (c) and the indefinite character
of the so-called dark line. Compare with figure 48. X 287.
(126-2L)

Figure ^^.-^Ballopora roinoso. iinilnre region.

The cingulum and its relation to the diaphragms is shown.
The wall lamin;ip in some cases nui across the axial region of the
wall and in other cases are offset at the axial plane. Farther in
toward the axial region, this species often shows a well defined
dark median line in tlie wall. X 287. (128-17.)

Figure 45. — Batostoma icincheUi, mature region.

This is the most extreme development of the dark median zone
in the Integrata. Note the relation of the diaphragms to the
secondary thickening of the wall. X 287. (188-20.)

Figures 46 and 47. — Sections of the wall in the mature region of tico specimens
of Heterotrypa prcenutia var. simplex.

These sections show the integrate and amalgamate phases of
wall structure in the same species. The relation of the dia-
phragms to the cingulum is also well shown, x 287. (188-21;
198-16.)

Figure 48. — Heterotryim prolifica, via tare region.

The most tyiiical amalgamate structure. The median dark zone
is hroad, and the lamina^ pass across with a gradual curvature.
The whole dark region has a distinctly graiuilar appearance under
high magnificat ion. owing to the concentration in this region of the
larger wall grannies mentioned in the text. X 287. (101-20.)

Figure 1!). — Eridotrgpa simulatri.r, mature region.

A mcinlicr <>t' tii(> Aninlgamata with a very sliarply d<»lin(>d
median dark line in portions of the wall, which hecomes inter-
i-npted and indefinite in other portions. The wall lamina» pitch
very steeply away from the axial region of the wall. Compare
with figure 45. X 287. (129-12.)

Figure 50. — Dil.mjiit nidciilaln. m a In re' region near the surface of the zoarium.
.\n extreme case of the ;inialgainn((> structure. The develop-
ment of (1,'irk tissue is very irregular, mikI there is no suggestion
of a definite median zone, nor of a duplex wall. X 287. (16(5-8.)

XXVUI.— liLi.i,, <;i;uL. Sue. A.M., Vol. 20. U)14

374 CUMINGS AND GALLOWAY MORrilOLOGV OF TRErOSTOMATA

I'LATE 15. — Morphology of the TuKrusroMATA.

FiGUKEfs Til AMD 't'2. - Ldiu/i 1 11(1 i iKiJ sccHdiix of I hc >< u [ic rficiiil rcnioii of a xiteOt-

irrii of ]>rlfi!ii(i iiiticiihihi.

Tlic overgrowth thai has in'cscrv cd (lie (h-licalc s]iiiH' s has been
delincatod in detail in figure HI. At / the em! of the spine has
probably iieeu crushed, thoujxh there may have originally been
som(> special organ there. 'I'he submerged portion of the spiue
is shown al *'. figure 51. In figure 52 the spine was embedded
in fine sill, which is not shown in the drawing. The rounded
projections at a and a' show the ai)pearance wliicli acauthopores
present in ordinary longitudinal sections. X 65. (iG6-S, 9.)

Figure 53. — Loiinilndinnl nccHon of a porlioii, of <t spine in the nyion s of
fifinrcs 51 and 52.

The wall is very finely laminate and the lumen distinct. X "100..
(16(>-10.) ■

Figure iJi.-^Longitudinal section of a spine at the level s', finiire 52.

The inner fascicle of laminae is the primary wall of the acan-
thopore. The fascicles of lamina? outside of this are secondary
deposits, probably laid on by the surrounding zooecia. X 287.
( 166-10. )

Figure 55. — Longitudinal f^ectio:! of the wall of Moulienlipora epidenvata.

This shows a fairly distinct median dark zoi:e, as in the lute-
grata. X 287. (56-22.)

Figure 50. — Hallopora splendens.

The growing edge of the wall, intact because of the protection
of an overgrowth. The edge is very thin and the wall lamiuie
have a very steep pitch. X 287. (230-8.)

Figure 57. — Similar section of the yroii-iiig edge of the icall of Dekagia
maeulata.

The edge of the wall is very smoothly rounded and the laminte
run across without interruption from zooecium to zooecium. x 287.
(145-9.)

Figure 58. — Section of the ivall of Stigmatella spinosa where it emerges from
the axial region.

The median dark zone seen at a.r disappears completely farther
in toward the axial region of the zoarium. This section .«hows the
manner in which the normal characters of tlie mature region are
gradually acquired. The beginning of a cingulum is shown at c,
X 287. (177-18.)

BULL. GEOL SOC. AM.

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MORPHOLOGY Of THE TREPOSTOMATA

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BULL. GE

51 ETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Vol. 26, pp. 375-388, PLS. 16-24 SEPTEMBER 3, 1915

"SlH,}' ONDITIOX OK mK A^OLCANOES OF SOUTHEEN

■It': ITALY 1

/!»*'''» '-'>■ "• '^^ WASH IXCiTUN A.\L) AiriTiLi; L. DAY

^^. :. ^J\r<i<l hcftirr llir. Socieh/ Dcrrinhfr -U. H^UJ/)

:l CONTENTS

■{ Page

Introdi ^:'h'Aj ."^To

Ve^^uviu^>;i.^f 376

Etna . . . . T^' :{80

Vulcaiio :584

Stromboli 387

N^TKODITCTORY

The stvulies of I);iy ami Slioplici'd- at Kilauea liavo demonsfratpd the
presence of water in the unaltered hna gases at this volcano, and that
chlorine and fluorine are present only in very small amount. They have
also shown that the gases at the time <d' their escape from the lava were
in a state dI' unstahic chemical c(niililirium. and that tliey were under-
going interreactioiis whicli, heing exothci'inic, might in |iart cxphiin the
maintenance of tlie high temperature of the lava.

Witlmut cntci'ing into discussion of these results, it may he said tliat
they Avere of such a character that it was deemed advisahle to cxteiul the
ohservations and studies to other Milcanoes. Ther(^ were several special
reasons for this.

Tlie confirmation (d' the presence of watt'r at <ither xolcanoes was a
matter of interest in coniKH-tiou with l^run's hypothesis, though this may
now he considered as delinitidy disproved hy the Kilauea evidence. The
possibility of intiiiial. e\<ithiuiuic gas reactions serving to account, at
least in paiM. for tin- hi-h temperature of the lava made it a matter of
importance' to ascertain the coniposii ion of tlie magmatic gases, and tludr
possible interreaclioiis, at nther volcanoes. Furthermore, as it is now
recognized that the distrihut ion of the rarer elements is correlated with

' Manuscript rccolvpii hy Ihp Secretary of the Society May '2r>. 1015.
2 Day and Shephrrd : .lour. Wash. .\cad. Scl.. vol. Ill, 1913, p. 4."i7 ; Bull. Cool. Soc.
Am., vol. 24. 1013, p. 573; Comptes Rcndu.s, vol. civil, 1913. pp. 958. 1027.

XXIX— Bull. Geol. Soc. Am., Vol. 2G, 1914 (375)

376 WASHINGTON AND DAY VOLCANOES OF SOUTHERN ITALY

the general chemical characters of the igneous magmas,^ it is of some
petrological, and possibly of vulcanological, interest to ascertain whether
the lava gases show analogous correlations with the composition of the
magma in which they are found.

We visited the volcanoes of Vesuvius, Etna, and the ^^olian Islands in
the summer of 1014. The general results of our observations and studies
of the material collected, including gases, salts, and rocks, will be pub-
lished later. The object of the present paper is only to \m\ on record the
state of activity and other conditions obtaining at the several volcanops
during June, >Tuly, and August. 11)14. Although the volcanoes were quiet
during the summer, the record may be of some value, as it is coming to
be generally recognized that study of the repose periods of volcanoes is or
may be of great importance in the interpretation of their phenomena
during activity, as well as useful in the prediction of eruptive periods.

We take this opportunity to express our great appreciation of the
valuable assistance and many courtesies rendered us by all the Italian
officials and scientists with whom we came in contact, among whom may
be specially mentioned : His Excellency the Minister of Public Instruc-
tion ; Professor A. Malladra, Director of the Vesuvius Observatory ; Pro-
fessor A. Ricco, Director of the Observatory at Catania : Professors L,
Bucca, Gaetano Platania, and G. Ponte, of Catania, and Professor J,
Friedlander, of Naples,

Vesuvius

Since the eruption of 1906 there has been a continuous condition of
"repose," the features of which have been described by several geologists.^
This period of repose has been the longest recorded since the beginning
of the eighteenth century. According to Mercalli's'^ data, the average
duration of the eleven well-marked repose periods which have followed
the more prominent eruptive climaxes since 1712 has been about 3.3
3^ears, while after the great eruption of 1906 some seven years elapsed
before the volcano gave any decided evidence of entering on a new period
of activity.

s H. S. Washington : Trans. Am. Inst. Min. Eng., 1908, p. 735.
* F. A. Ferret : Am. .Tour. Sci., vol. xxvili, 1909, p. 41."^.
G. MercaUi : Rend. Ac. Sci. Nap., vol. xix, 1913, pp. 134. 137.
A. Malladra : Rend. Ac. Sci. Nap., vol. xviii, 1912, p. 224.

A. Malladra : Rend. Ac. Sci. Nap., vol. xix, 1013. p. 153 : Boll. R. Soc. Cieog.. 1914.
p. 753 ; Rend. Ac. Sci. Nap., vol. xx, 1914 ; Boll. R. Soc. Geog. Ital., 1914, p. 1237, with
map of crater ; Zeits. Vulk., vol. i, 1914, p. 104.

I. Friedlander : Natiirw. Wochens., vol. x, 1911, p. 454.

I. Friedlander : Naturw. Wochens., vol. xii, 1913, p. 389 ; Peterm. Mitth., 1912 ; maps
of the cone and crater of Vesuvius, Naples, 1913.

O. de Flore : Atti. Ac. Sci. Nap., vol. xv, 1913 (contains bibliography) ; Rend Ac. Sci.
Nap., vol. xix. 1913, p. 106.

6G. Mercalli : Vulcani Attivi, Milauo, 1907, p. 207.

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VESUVIUS 377

Since 1906 the volcano has been in a solfataric state, no outflows of
lava or definite explosions having taken place. With the exception of
certain portions of the crater floor, to be mentioned later, the changes
have been largely those due to non-volcanic agencies.

Fumarolic activity began shortly after the cessation of the eruption ;
that is, as soon as the vapors could open a way through the superincum-
bent ash. The chemical effects of these hot, very acid gases have, of
course, considerably disintegrated the rocks and have contributed ma-
terially to the progressive demolition of the cone.

In the Atrio del Cavallo, close to the face of Monte Somma, is a group
of about 30 fumaroles, some of which are shown in plate IG, whicli re-
semble the so-called hornitos of Jorullo. These have been described
especially by Malladra^ and Bernardini.^ They have formed relatively
low, domal elevations, from one to eight meters high, with circular or
elliptical outlines, elongated parallel to the Somma scarp. These accu-
mulations are composed of ashes and claylike decomposition products,
cemented by sulphur and various salts, chiefly sulphates. Those which
form a row nearest the central cone have a constant temperature of about
97° C, and the analyses of the gases by Bernardini show a decided per-
centage (7-11) of HoS. Those in the next row show about the same
temperature, tliough somewhat variable and with only traces of HoS,
while those nearest the Somma scarp are still more variable in tempera-
ture' and willi IK) IToS. At tlie time of our visit the activity of all these
fumaroles appeai'cd to b;i\c diminished nearly to the point of extinction.

The fiiniaroles inside the crater are of special interest and were in a
state of considerable activity, the humidity which prevailed during our
stay rendering them more prominent than would have been the case in
dry weather. Some were also in action on the upper part of the outer
slope, these being confined to the north and northeast sections. The tem-
peratures of these have been measured by Perret,. Mercalli, Malladra, and
Friedlander and are somewhat variable. Their temperatures and activity
seem to be decreasing.

Inside the cone fumaroles were in activity in all parts of the walls. Of
these, those on the north and northeast form a prominent group, or
"battery," as such a line of fumaroles has been named by Mercalli. The
temperatures of tUesL' have not been measured, as they are inaccessible.

The largest, most prominent, and most active battery is on the south-
west and west inner scarp. These begin in the southwest, below the point
to which tourists are taken by the guides, about 20 meters al)<)ve the
bottom of the crater, and extend obliquely upward to a ]Miirit l)elow the

« A. MiilliHlrii : Ucml. Ac. Scl. Nap., vol. xlx, 1S)13, p. ir.:j.
T I.. HiMiiuidiiii : Ki'ud. Soc. CLlui. Itul. Niip.. 1913.

378 WASHINGTON AND DAY VOLCANOES OF SOUTHERN ITALY

ruined funicular station house. Of these the greatest is the Fumarola
(lialla (Yellow Fmnarole), so called by Malladra because of the bright
yellow and orange coloration of the cliffs in its vicinity. This was in a
state of intense activity, great clouds of vapor issuing from it. The tem-
perature of this fumarole as measured by Capello in September, 1911,
was 138°, while Malladra found 295° in May, 1912, 330° in September,
and 347° in October, 1913.

Since the eruption of 1906 there have been continual slips of material
from the crater walls. Especially noteworthy slides of large sections of
the southwest scarp took place in March. 1911, and January, 1913, the
last hciiig coincident with and apparent!) due to a marked subsidence in
the southei'ii part of the crater floor.

In April, 1913, there took place what was regarded by ]\Iercalli as the
beginning of a reawakening of activity at A^esuvius, shown by a decided
increase in the number and activity of the fumaroles in the crater floor,
especially near the slight subsidence of 1913, and by almost daily slight
local earthquake shocks. This culminated during the night of May 9-10
in the formation, at the site of the previous subsidence, of a large funnel
{Inihuto), estimated to be some loU meters in diameter and about 70
deep, from which issued continuously a dense column of white smoke.
On the -")tli of July direct connection with the interior Avas established l)y
the opening of a "bocca," or mouth, near t!ie lowest point of tlie fuiuiel
and just below the steep scarp formed Ity the great subsidence. This
orifice was incandescent even in full daylight, and from it issued large
puffs of yellowish smoke, accompanied by loud roarings.

Taking advantage of the acquired relative stability of the long slope
formed by the slide of the previous March, Doctor Capello, at that time
assistant at the Vesuvius Observatory, made the first descent into the
present crater in September, 1911. In May, 1913, Dr. A. Malladra,
Director of the Observatory, descended the crater for the first time, and
has since then gone doAvn several times, on some occasions accompanied
by other scientists. These descents were made from a point on the south-
southeast rim near the tourist viewpoint, the slij) of 1913 having ren-
dered parts of Capello's route impracticable. One of us (Washington)
had the opportunity of accompanying Doctor Malladra in a descent on
June 9, 1914, during which observations were made of the conditions then
obtaining within the crater.

It may be mentioned that the intentioii at the outset was not to make
the complete descent, Init to discover a favorable locality for the placing
of a steel cable for the transport of instruments and specimens into and
out of the crater. On this account no thermometers, collecting tubes for
gas, protective masks, or instruments were carried, and consequently

VESUVIUS 379

some higlily desirable observations could not lie made. On attainino; a
certain distance, however, it was found that a return hy tlie same route
was impossible, so that we were fortunately oblioed to ,siO to tlie bottom
and ascend by the usual track.

The descent was begun at a low point on the northwest rim, about 200
meters north of the' abandoned funicular station. The upper part was
steep, tlie wall consisting of faces of lava-sheets interbedded with some-
what consolidated agglomerate and beds of scoria. There were no well-
dclined fumaroles along this portion, Init eonsideralde steam, higlily
charged with HCl and SOo, was emitted fi'oin the crevices.

.Vt a depth of rather over 100 meters t!ie heail of a talus slo[ie at least
'<!()0 meters long and with a slope of 31° was reached, ajid the descent
(■out iiiued down this.

Tlie floor of the crater is somewhat domed toward the center, covered
with ash, in wliicli small, loose augite crystals may be gathered, and is
strewn with many angular blocks fallen fr(nn the walls above. Many of
these are several cubic meters in size. No saline incrustations were seen,
probably because of their removal by the prolonged rainy weather. There
were no rumai'oK's projier, a central group formerly |)resent having ceased
activity after thi' sulisidence of 1012, but hot vapors issued i-ont iiiiiously
from the ei-eviees ami the loose material. HCl and SO, could be readily
detected. There wtM'e also pi'eseiit uiupiestionably SO., and pi'ohalily CO.,.
I, lit no [|.,S was ol)ser\ed. The blue mist produced by these gases and the
ahuiidant steam made good ])hotographs impossible.

At the foot of the north and east walls was a long, narrow, and deep
cresci'iitie \allev. which was i'ornie<l toward the end of November, 1911.
The highest |ioin1 of the lloor. near the center, is 327' meters below the
higliest point of the rim, and the depth of the \alley is ahout (id meters.
as determined by Malladra in l!tl3.

In the southwest part of the Hoor is the funnel, the diameter of which
was judged to he ahout l"in meters, with a depth of ahout ;'>(! meters.
The sides of this slope at 30° and are composed of loose ash and scoria,
with comparatively few laig'e blocks.

Sli<ditlv aho\e ami to the northwest of the lowest iioint of this is the
'•hocca" or mouth — a roughly circiilai- oi' elliptical orillce some lO-lTi
meters across — with rougli, approximately vertical walls, which could he
approached within a few meters. Beyond this on the north was a vertical
wall of lava, sprinkled with drililets and small stalactites of lava.

l''i'(iiii this inoiilh issued two ji^ts of smoke, in large rounded piifFs,
every four to six seconds, accompanied hv rather huid roars, while a con-
tinuous low rumhling could he heard helow. The eastern jet was some-
what the lariier. and the pulls nf the two were not usually synelironous.

380 WASHINGTON AND DAY VOLCANOES OF SOUTHERN ITALY

though sometimes exactly so — apparently a chance effect. The color of
the smoke of both columns was generally a tawny yellow, changing sud-
denly every now and then to white. As felt by us, the smoke was warm
but not oppressively hot, though the abundance of HCl and SO, vapors
made it and the air in the funnel rather suffocating to breathe.

No liquid lava nor red glow on the smoke could be seen, but the vicinity
of the bocca was sprinkled with small fragments of very fresh, light
brown, pumiceous lava, to which adhered short (5-10 cm.) strands of
Pele's hair. This pumice was thought l)y Doctor Malladra to have been
ejected Ijut a few days before. An analysis of it, recently made and to ])e
published elsewhere, shows that it closely resembles in chemical compo-
sition the lavas of 1872, 1903, and 1906. There were also many frag-
ments of a porphyritic lava, much decomposed by the acid vapors, but
with the euhedral augite phenocrysts fresh and unattacked. According
to Doctor Malladra, this dated from December, 1913. An analysis (by
H. S. W.) of salts collected by Doctor Malladra in May, 1913, from near
the orifice, shows that they consist largely of aphthitalite, a double sul-
phate of potassium and sodium, with less alum and ferronatrite and a
very small amount of cupric chloride.

On the first part of the ascent, up a long talus slope of large blocks,
the very active Yellow Fumarole was passed, but unfortunately, owing to
the lack of protective masks, it could not be approached very closely, and
no temperature measurements were possible in the absence of a ther-
mometer. On this slope, which extended above the bocca and along the
battery of f umaroles, the acid vapors were very troublesome.

Continued rainy weather caused us to abandon Vesuvius temporarily
for Etna, and shortly after our departure, as we were informed by Doctor
Malladra, the crater filled with a "sullen" heavy smoke, which slowly
poured over the edges and absolutely precluded any descent. Doctor
Malladra has recently (December, 1914) written us that there is much
increased activity, a small cone having been formed in the funnel above
and around the opening and the funnel being half filled with lava.

Etna

The last great eruption of Etna took place in March and April, 1910,
when a series of bocche (mouths) was formed along a north and south
(radial) fissure which opened on the south slope of the mountain. These
formed a line of explosion craters followed by cones of ash and scoria, to
the last and largest of which, situated some 1,324 meters below and 5.5
km. to the south of the summit, was given the name of Monte Kicco.
From the south side of this cone issucil the great stream of lava, which

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ETNA 381

tiowed almost due south for a distance of about 10 km., nearly reaching
the Monti Rossi, near Nicolosi.^

It was succeeded by a period of strombolian activity in the central
crater, and at tlie end of May, 1911. a lai'.ue bocca opened on the main
platt'oi'm, northeast of and close to the summit cone.^ This was followed
by a short but \ iolent eruption in September, 11)11, on tbe northeast
tlank, but far down the mountain, some 6 km. from the summit.'" Since
then the volcano has been quiescent and fj-enerally in a solfataric condi-
tion, with only occasioiial strcmibolian activity.

Tlie summit crater of Etna is situated approxiniatel\' in the center of
an ash cone 1,()()0 feet hioh rising from the Piano del Lago (cf. ])late IT).
It is nearly circulai' in form, about 500 meters in diameter, and receives
its color for the most part from fresh, light gray asii which, dni'ing tlie
period of tnir visit, was thrown out almost daily. The crater rim, except
for a small section just above the observatory, is a sharp edge formed by
the steep outer slope of the cone and tlie precipitous wall within, due to
slips which the extensive concentric cracks show^ to be the present process
of enlargement of the crater. The inner walls, with the exception noted,
are nearly vertical near the top, and will average 90 per cent in pitch
froiii to]) to bottom Oil the northeast, north, west, and southwest walls.
The southeast wall appears to have sagged rather than broken ahrui)tly,
and presents a somewhat rounded contour both outward and inwai'd for
a i'i'W meters, beyond which it breaks abruptly over a talus pile on the
bottom of the crater below. The depression caused by this sagging is no
iiKtre than \~y or 20 meters. It affords a platform from which a beautiful
\ icu of the intefioi' of the crater can be obtained in those i-ure intervals
when the (;rater is free of smoke. It is, nevertheless, a most treacher-
ous point because of the concentric cracks which cross it and which have
hfcn bi-idged over by recent ash so as to be entirely invisible. The view
of the crater shown in plate 18 was taken from this point.

At the time of our visit in June and July the central cone and the
suri'oiiiiding plateau wei'e covci'ed with a layer of line, ilark gray ash,
iVoin I.') to ."ill i-ni. thick, with many small stones (10 to ."lO em. diameter)
iiiilieddcd III the ash. The greater part of this had fallen about two
months p!'e\ ioiisl v. according to Allio liai'hagallo. the custodian id the
ob.servatoi'v. It is ipiitc practicable to walk entirely aroun<l the rim of
the crater, though the fo<iting is e\er\ where slini\ and the ga>e> to lee-

" The best descrii>lii>iis of lliis cnijiiioii aii' ii> I"- limnd in impers \<y S. .VrcirtlaooiKi.
A. Ulcco, O. de Fioif. I". N'iiiassa de Ki-Kiiy. 1'. Sit ila Starrublm. and I., rafrara in .\ttl.
Aw. (iloen. (5). vol. iv, lull, and in a papt'i- liy <!. 1'onte in .\ttl. .\i'<-. Line. iri). vol.
vlll, li»ll, p. iW.'..

" ( 'f. .\. Kicco: .\lli. .\i-c. (Uwn. i ". I , vol. iv, llMl, nicni. xi.

••Gaetano IMalanla ; Hlv. tleog, Ital., vol. xlx. 1!»1L*.
G. Ponte: Boll. Ciiil) Aip. Ital.. vol. xll. 10i:i. No. 74.

382 WASHINGTON AND DAY VOLCANOES OP SOUTHERN ITALY

ward strongly acid, dust-laden, and very irritating. This ash was damp
in many places, especially near the top and down the south and southeast
slopes, where it was impregnated and covered with salts. Most of these
saline incrustations were white, but there were also yellow and greenish
patches, these last being especially prominent on the southeast slope,
where they extended quite to the bottom of the cone and are well shown
in plate 17. The salts, mostlj'^ white, were also abundant down the north
slope and about the bocca on the northeast, as shown in plate 19. A pre-
liminary examination shows that these salts are mostly mixed sulphates
and chlorides of soda and less potash and ammonia. In places there was
sufficient copper present to copper a knife blade.

Considerable steam was rising from the south and east slopes of the
cone, issuing from small fumaroles at possibly fifty more or less fixed
spots. The other slopes of the cone were quite free from these emanations.

The inside walls of the crater from top to bottom are covered by a
somewhat festooned arrangement of fresh ash which reveals little struc-
ture to the observer. The bottom of the crater is something over 450
meters below the present rim, and appears to be entirely inaccessible, not
alo]ie because of the steepness of the walls, but because of the treacherous
ash deposits and the smoke, which is usually so thick that few who have
made the climb to the summit have been rewarded with a view of the
interior. We were fortunate enough to obtain a clear view of the bottom
of the crater, obscured only l)y a thin film of bluish smoke, on two occa-
sions— the smoke, by the way, being much more transparent to the eye
than to tlie camera, even when the lens is moderately screened against
blue. A photographic view down to the bottom of the crater is therefore
exceedingly difficult to obtain and is not altogether satisfactory when
obtained (plate 18).

In appearance the bottom of the crater is nearly flat in the west half
aiul is usually covered with ash. The guides are accustomed to call atten-
tion to five openings, of wdiich only two could be clearly distinguished at
the time of our visit — one a round well perhaps 40 meters in diameter and
20 meters deep, with a flat floor of ash. This well is located near the
north wall, a little to the west of the middle, and has at least two openings,
both in its side walls. The smoke which emanated from this well at in-
tervals came invariably from the northeast opening, and usually emerged
from the top of the well into the open crater. Occasionally it appeared
to roll across the floor of the well and disappear into the opening in the
opposite wall without emerging into the crater at all — an extraordinary
phenomenon which is perhaps to be explained through a subterranean
connection between the central crater and the outside crater, to be de-
scribed below. No fresh lava was visible in the well or elsewhere in the

BULL. GEOL. SOC. AM.

VOL. 26, 1914, PL. 18

INTERIOR OF ETNA CRATER FROM SOUTHEAST

Note the steepness and stratification of the ashdraped walls and small fumaroles above. Smoke
from the "well" is seen In the lower right hand corner.

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ETNA 383

crater during the period of our visit, but an excursion to the top in the
early morning of July 23 made by the guides alone revealed several
bright cracks, both within the well and to the eastward of it.

The second conspicuous opening is a cone filling the eastern half of
the crater floor and perhaps 100 meters high. The present appearance
of this cone indicates an explosive origin. This opening is exactly oppo-
site the outside crater and immediately suggests a connection between the
two. We did iiot, however, during the limited period of our observations,
discover any connection between the occasional explosions emanating
from iliis coiu> ;iiul tlio activiiy of ilir outer crater. The explosions from
this inner cone were ofteji vioIiMii and yielded treniciidous volumes of
smoke, wliicli emerged in the usual cauliflower form, very black and
heavily dust-laden (plate 17). On one excursion to the summit during
the evening of July 16 a considerable outburst was seen coming from this
opening, accompanied by a flash of light and a dense cauliflower cloud,
but with no sound of explosion nor of falling rocks following the flash.
No incandescent matter was visible at that time. On another occasion
(July 23) loud explosions were frequent, accompanied by the usual caidi-
flower clouds, but no flashes.

In appearance this inner cone is jagged and irregular, though roughly
square in form, with very steep, smooth inner walls closing together to a
narrow black throat in which all detail was lost in smoke, even on the
most favorable days. The outer surface of the inner cone is concealed
under fresh ash. Surface slides are frequent and appear to indicate that
the ash is dry and has the maximum steepness of slope at which such
material can come to rest.

The bottom of the crater Avas over 450 meters deep, according to meas-
urements with a plummet-line in the hands of our guides, A. Barbagallo
and D. Caruso, who returned to the crater after our departure for that
purpose. The line did not quite reach the bottom.

The new outer **bocca," or crater, on the northeast slope of the cone is
about 80 meters below the summit. It is shown in plate 19. When first
formed it was roughly triangular and about 100 meters across. It is now
approximately circular and about 200 meters in diameter. Owing to falls
of the sides, especially on the side toward the main crater, it is cutting
rapidly into the cone and its southwest edge is now less than 100 meters
from the crater rim. So far as could be seen through the clouds of smoke
which filled it, the sides are vertical, but not even a glimpse of the bottom
was to be had and no estimate of its depth was possible. No glow or flash
could be seen in this crater during any of our visits, day or night.

There was a constant emission of clouds of a dense, dark gray smoke,
which came in huge puffs at irregular intervals, sometimes welling slowly

XXX- Rfi-r- r,For.. Soc. Am.. Vor,. iR, 1014

384 WASHINGTON AND DAY— VOLCANOES OF SOUTHERN ITALY

up and sometimes sent high into the air, always accompanied by a loud
noise, as of hissing steam, which was nearly constant in volume. The
sound from this crater was never paroxysmal in character, though the
smoke puffs frequently appeared so and Avere often of great volume. The
character of this noise and the forms of the cloud jniffs led us to believe
that there \yas more tlian one orifice below. The smoke was hot, very
acid, and suffocating, and field tests revealed the presence of H^O, HCl,
SO,, and H2S.

From the observations made it was evident that Etna is now sliow-
ing Ijoth solfataric and strombolian phases at intervals witliout marked
activity. It was the ojiinion of various observers of the volcano, espe-
cially Professors Platania and Ponte, Custodian Barbagallo and the guide
Caruso, that the activity of June and July, of Vhich we were witnesses,
was distinctly greater than it had ])een during the previous six months or
so, and it was regarded as probable that a renewal of more intense activity
is not far off. At the rate at which the outer "l)occa" is cutting into the
cone, it seems certain that within a short time it must break througli into
the main crater and may precipitate a more serious disturbance fheii,
tliough an eruption from the main crater has been in recent times a
somewhat rare occurrence at Etna.

VULCANO

Since the last eruption of Yulcano, in 1888-1S89, the volcano lias been
in an almost continuous state of solfataric activity and lias attracted little
attention. Of tJie papers which deal with this aspect of the volcano may
be cited those by Bergeat,^^ Ponte,^" and de Fiore,^^ the latter describing
the fumaroles in considerable detail. The general relations of the present
crater, the crater walls of the early phase, and Vulcanello are shown in
plate 20, taken from the south end of Lipari.

The walls of the crater — the so-called Fossa di Yulcano — are conijiosed
of fragmentary andesitic material, much of which was thrown out by flic
last eruption, which raised the rim considerably. This material is a
coarse agglomerate, more or less consolidated and cemented by the abun-
dant salts and by the decomposition products formed by the action of the
acid vapors. Large angular bombs, one of wliich is reported to have liad
a volume of 45 cubic meters, are scattered over the slopes. On the crater
slopes and rim these bombs, even the largest, are gradually disintegrating,
traversed by fissures due originally to internal strains and intensified by
the action of the acid vapors, so that they eventually break doA\T.i into a
heap of angular fragments.

>i A. Bergeat : Die Aolischen Inselu, Abh. nay. Ak. Wiss., vol. xx. ISDO.
^G. Ponte: Attl. Ace. Gioen.. vol. iii. ISOI.
'SQ. de Fiore : Zeits. vulk., vol. i (2), 1!)14, p. .57.

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VULCANO 385

The crater (plate 21) is circular, about 600 meters in diameter, the
western and northern rim rather flat, while to the southwest, south, and
east the rim is lost against the steep wall of the first phase crater. It is
much less deep than it was prior to the last eruption. The interior shows
two well-defined terraces, which run ahnost completely around the circle,
the upper being about 25 meters below the southern rim and the second
about 15 meters below the first. The slopes between these are gentle;
not over 25°.

The second terrace forms the edge of the funnel of the crater, tlie
bottom of which is about o() meters l)elow the terrace and with sides s1o[j-
iiig (except oil Ibc iioi'th ) at about 32°. The Ixtttoiii of this fiiiiiiel
(about 70 meters below the northern rim) is formed of two cii'tndar,
shallow depressions, each about 25 meters across and separated bv a nar-
row ridge of ash and agglomerate. The small lake previously occupying
the bottom has disaj^peared. and the floors of the two basins are dry and
covered with salty crusts in varicolored patches of fawn, buff, yellowish,
gray, and white. The southern basin shows little activity, but from
around the northern one there is considerable emission of hot vapors, and
an active fumarole exists on the steep north wall, witli abundant deposi-
tion of sulphur.

The fumarolic activity is intense over much of the cone antl may be
referred, as ])ointe(l out by de Fiore, to two distinct types — the diffuse
exhalations and the fumaroles proper.

The (ii'st consists in a gentle, quiet, and noiseless emanation (d' hot
vapors, whicli a|)|)eai' to he mostly steam, with 80o and litth' oi- no 1 1 CI
or U.S. through ci'evices and the less coherent lapilJi and ashes, accom-
))anied by the deposition of more or less abundant salts but little or no
sulpliui'. Exhalations of this type are abundant at the Ixittom of the
crater and over the inner slopes and crater rim. especially on the north.
They are especially so in the north upper sloius oxer the so-called Piano
delle Fumarole and below this as far down as about the 100-meter level.
Here there is a broad zone which is so thickly covered with salts that one
sinks ankle deep in them.'^

For the most part these salts are pure wliite. but there are extensive
l)atches of ydlow, bi-igbt orange, yellowish brown, grt'cnish gi'ay. and at
(me place the snowy white salt surface is niai'ked with patches of pale
blue and lifight gi'ccii, (hie to copper. Tliese salts are damp and warm to
the hand.

In tlie crater on the northern rim and generally o\er the Piano delle
l^'umarole tiie saline de|>osits are imt so thick and ai'e of a ditl'erent cliar-

" It may be iiulcd ILiil llic linn- of oiir visit (in August) was cxofptioually favorable
for the I'djjiM'liini and stiuly of these salts, as no i-alii liad falliMi since Jauuary.

386 WASHINGTON AND DAY VOLCANOES OF SOUTHERN ITALY

acter. Here they are dry and do not form thick continuous beds, but
occur as narrow streaks along innumerable crevices in the ground, or else
delicate flat "rosettes" from 1 to 5 cm. in diameter and with concentric
series of petals (plate 22), or else tulip-like forms.

A preliminary examination of these salts shows them to consist for tlie
most part of sulphates, chiefly of alumina and potash, with less soda and
ammonia and little lime and magnesia. Iron is present in all, even the
purest white specimens. With the exception of a few bright yellow syjeci-
mens, colored by ferric chloride, these deposits seem to be quite free from
clilorides, and lioric acid, while present in certain spots, does not seerf to
be as abundant as it was before the eruption. It appears that thiosul-
phates are present in the salts from inside the crater, wliile tliey are
absent from those on the crater slopes. These salts are now being investi-
gated chemically and optically.^^

The fumaroles proper were very active and numerous, occurring both
over the upper part of the cone and in the crater. The gases issue either
from beneath the large bombs which strew the rim and the inner slopes
of the crater or else from narrow, irregular holes in the ground. A small
group of tliese fumaroles is seen at the bottom of the crater, near the
north wall, and many of them (possibly fifty) are scattered over the inner
north and east slopes of the crater. There is also a "battery'" of them
issuing from the steep face of the tuff beds which form the inner wall of
the early crater on the south and soutliwest. On the Piano delle Fumarole
itself there are few or no fumaroles of this type at present except at the
west end of the terrace, above the upjier end of the Pietre Cotte, where
several occur. The most important and most active group is tliat just
below the east end of the Piano delle Fumarole, around the upper end of
the old conveyer cable, above the Forgia Vecchia, at an altiturle of 210
meters, shown in plate 23.

These fumaroles give off a great deal of Avliite vapor — chiefly steam,
with much SO, and FI^S — which issues with considerable violence and a
loud hissing noise. Their temperatures generally varied from 99.0° to
10!)°, but that of the largest was US..1°. They do not deposit salts, but
an abundance of sulphur, in masses of transpnrent bright yellow acieular
crystals of the utmost delicacy, whicli are dewed with drops of water.
These crystals are of the moiioi-linic modification and on contact bi'eak
down to powder and lose theii' transparency through inversion to the
orthorhombic form.

A characteristic of these fumaroles, as noted jjy de Fiore, is their ap-
parent permanency of location. Some of the larger ones antedate the
great eruption, and the largest, that at La Portella, shown in plate 23, is

i^Cf. .T. Koenigsberger autl W. J. MiiUfr : ZeUs. Vulk., vol. i, 11U.5, p. ]9(;.

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STROMBOLI 387

possibly identical with one seen by Dolomieu in 1781. The diffuse ex-
halations, on the other hand, seem to lack this stability and shift their
locations. While the two types are quite distinct in their normal and
extreme forms, yet there are intermediate forms, some diffuse exhalations
from cracks depositing sulphur needles, and a few of the fumaroles
proper being accompanied by salts.

Stromboli

This volcano is usually cited, froiu ilio time of I'liny nn, ns lipi'ng in a
continuous state of eruption. The record of its activity is. however, inter-
rupted and very scanty, and recent investigation leads to tlie conclusion
that "Stromboli presents long periods of varied, but for the most part
moderate, activity, interrupted by relatively brief periods of repose." ^^
Violent eruptions would seem to be infrequent, the last having taken
place in 1907.

The crater was visited on August 7 and 12, 1914, and it was seen that
marked changes had taken place since it was last reported on in 1909.^^
The large gulf or funnel of 1907 has been filled up and the crater plateau
forms a plain about 250 meters below the crest above, with a low ellipti-
cal, dome-shaped elevation occupying the northwestern part, built up of
material ejected from Bocche B and C. On the north the plain ends
sharply at the beginning of the Sciarra. The plateau is practically inac-
cessible because of the constantly falling stones and the precipitousness
of the other three sides. Five active vents were seen." A view of its
general features is sho^vn in plate 24, taken from a point above, to the
north ( X in figure 1 ) . It was impossible to reach a nearer point below
the Filone Baraonda on account of falling stones.

The most prominent and violent vent was that marked A in the an-
nexed sketch map, figure 1, based on Bergeat's map. This is near the
head of the Sciarra, just below its upper edge at the eastern end, so that
it was not visible. This exploded at short, irregular intervals with a
sudden loud roar, like the discharge of a large-caliber gun. Many red-
hot fragments of half-molten rock were ejected to a height of several
hundred meters, accompanied l)y a tall column of generally brownisb
smoke. This vent seems to be the oldest of those now present and was
apparently in existence as far back as 1776 and 1782.

Bocca B, near the lower end of the Filone di Baraonda, an orifice
about 10 meters in diameter, was in continuous activity. There was an

'" Oaetano Platanla : Ann. Uff. Centr. Met, vol. xxx, part 1, 1910, p. R.
" P. A. Perrct In Platanla, loc. clt.

>8 As lliclr detailed description and relations to earlier vents will be taken up In a
separate paper, they will be only briefly described here.

388

WASHINGTON AND DAY VOLCANOES OF SOUTHERN ITALY

f^' ^MiUMs^

■ • ...' ■'■'^;^'y.''^'v•''l■^^v•'"'.•''^ '

r'/<j';vS

intermittent emission of many half-molten stones, accompanied l)v pufl's
of generally white smoke, few explosions. l)ut a pretty continuous roai-.
The stones did not rise much above TjO meters or so, many of them much
less. The hole below was filled with thin, long, wavering, bright red,
Hamelike tongues, Avhich seemed to be spurts fnmi the liquid lava not f;ir
below. This vent seems to have been in existence as far back as 18!>]. if
not earlier.

Bocche C and I) are of m <]uite different type and much k'ss acti\('.
(" is in a solfataric state and emitted puffs of white smoke, with little

___^ noise and without stones.

^^mmm^WT^^'^'- ^ I I) showed little aetivity,

occMsjoiially lining (|iiietly
with sluggisii yellow smoke.
(' seems to l)e later than 1).
as its outline cuts into that
of the latter.

Tlie last bocca. F, is the
most ])eculiar. It "blows
oft'"' at intervals of from 20
to 10 minutes from a small,
shallow, scarcely noticeable
depression in the scoria-
strewn floor near the east-
ern Filone, visible to the
right in ]date 24. There is
a loud, startlingly sudden
blast, like tlie letting off of.
steam from a gigantic
boiler, am] the rapid ascent
of a narrow, very tall col-
umn of white or gra}^ smoke from a small orifice which makes its appear-
ance at the bottom of the depression. The edges of the orifice become
red hot and there is a small, low spatter of molten material. The blast
continues with increasing loudness for from half a minute to two minutes
and then ceases, generally suddenly. During the last few seconds the
dense smoke generally ceases and the noise of the blast continues with
the emission of faint whitish or bluish vapor. After the outburst the
orifice closes and the depression becomes again black and scarcely detect-
able.

There was not much fumarolic activity, this being confined chiefly to
the battery (F on the map) along the Filo del Zolfo and some slight vapor
spires over the crater floor. The general smoke, as observed on the ridge
above the crater, was acid and smelt somewhat strongly of SO,.

%';^' .' Porta delle Croci

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I'"KaRE 1. — Sketch Maii of tlic ('ruler of Strtimbnli

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BULLETIN

OF THE

Geological Society of America

Volume 26 Number 4
DECEMBER, 1915

JOSEPH STANLEY. BROWN. EDITOR

PUBLISHED BY THE SOCIETY
MARCH, JUNE, SEl^EMBER, AND DECEMBER

CONTENTS

Pages
Proceedings of the Summer Meeting of the Geological Society of
America, held at the University of California and at Stanford
University, August 3, 4, and 5, 1915. J. A, Taff, Secretary
protem. 389-408

Proceedings of the Summer Meeting of the Paleontological Society,
held at the University of California and at Stanford University,
August 3, 4, 5, and 6, 1915. Chester Stock, Secretary pro
tern. 409-418

I. On the Relationship of the Eocene Lemur Notharclus lo the
Adapidae and to Other Primates. 11. On the Classification
and Phylogeny of the Lemuroidea. By W. K. Gregory - - 41 9-446

Problem of the Texas Tertiary Sands. By E. T. Dumble - - - 447-476

A Stratigraphic Disturbance through the Ohio Valley, Running from
the Appalachian Plateau in Pennsylvania to the Ozark Moun-
tains in Missouri. By J. H. Gardner 477-483

Index to Volume 26 485-504

Title-page, Contents, etcetera, of Volume 26------- i-xxi

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Communications should be addressed to The Geological Society of America,
care of 420 11th Street N. W., Washington, D. C, or 77th Street and Central
Park, West, New York City.

Entered as second-class matter in the Post-Office at Washington, D. C,

under the Act of Congress of July 16, 1894 \

PRESS OF JDDD & DETWEILER, IXC, WASHINGTOX, D. C.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA
Vol. 26, pp. 389-408 November 22, 1916

PROCEEDINGS OF THE SUMMER MEETING OF THE GEO-
LOGICAL SOCIETY OF AMERICA, HELD AT THE UNI-
VERSITY OF CALIFORNIA AND AT STANFORD UNIVER-
SITY, AUGUST 3, 4, AND 5, 1915.i-

J. A. Taff, Secretary 'pro tern.

CONTP^NTS

Page

Session of Tuesday, August 3 .390

Titles and abstracts of papers presented and discussions thereon.... 391
Epigene profiles of the desert [abstract and discussion] : by

Andrew C. r^awson 391

Bajadas of the Santa Catalina Mountains, Arizona [abstract and

discussion] ; by C. F. Tolman, Jr 391

Origin of the tufas of Lake Lahontan [abstract] ; by J. C. Jones. . 392
Some physiographic features of bolsons [discussion] ; by Herbert

E. Gregory 392

Sculpturing of rock by wind in the Colorado Plateau province;

l)y Herbert E. Gregory 393

Session of Wednesday, August 4 .393

Titles and abstracts of papei-s presented and discussions thereon .393

Some chemical factors affecting secondary sulphide ore enrich-
ment [abstract and discussion] ; by S. W. Young 393

Itole of colloidal migration in ore deposits [abstract and discus-
sion] ; by John D. Clark 394

Examples of progressive change in the mineral composition of

copper ores [al)stract and discussion] ; by C. F. Tolman, .Tr. . . . 394
Sericite, a low temperature hydrothermal mineral [abstract] ; by

A. F. Rogers 395

Dinner 39.^)

Session of Thursday. August 5 .39,5

Titles and abstracts of pajiers presented and discussions thereon 39.5

Physiographic control in the Philippines [abstract and discus-
sion] : by Warren D. Smith 395

Origin of the basins within the hamada of the Libyan Desert

I abst ract] ; by William IT. Hobbs .396

Limited effective vertical range of the desert sand-blast, based
on observations made in the Libyan Desert and in the Anglo-

Egyi)tiaii Smlan | iihstract] ; by William H. Hobbs .396

('liaractcristics of tlic Lassen Peak eruptions of May 20-22. 19ir>
[abstra<-t mimI .lisciission | : by Kuliff S. Holway and J. S. Diller. 397

* Manuscript rpcoivcd 1)\ the Sccrt'tjirv ni' tin- Society Oct.ilwr 1.'^. 101.".

XXXI — Boll. Geol. Soc. Am., Voi,. 26, 1014 ^389)

390 PROCEEDINGS OF THE CALIFORNIA MEETING

Page

Geology of portions of western Washington [abstract] ; by
Charles E. Weaver 397

Problem of the Texas Tertiary sands [abstract] ; by E. T. Dumble. 398

Pisolites at San Antonio, Texas [abstract] ; by Alexander Deussen. 398

Geologic age of the Coal Creek batholith and its bearing on some
other features of the geology of the Colorado front range [ab-
stract and discussion] ; by Hyriun Schneider 398

Occurrence of flow-breccias in Colorado [abstract and discussion) :
by Horace B. Patton 399

Geology of a portion of the Santa Ynez River district, Santa Bar-
bara County, California [abstract] : by W. S. W. Kew 401

Interesting changes in the composition of the Salton Sea [ab-
stract] ; by A. E. Vinson 402

Examples of successive replacement of earlier sulphide minerals
by later sulphides at Butte, Montana [abstract and discussion] ;
by J. C. Ray 402

Structure of the southern Sierra Nevada [abstract] ; by John P.
Bulwada 403

A measure of arid erosion [abstract] ; by Charles Keyes 404

A possible causal mechanism for heave fault-slipping in the Cali-
fornia Coast Range region [abstract] : by Harry O. Wood 404

Structural features of the Tsin Ling Shan [abstract] ; by George
D. Louderback 40~i

Certain structural features in the coal fields of New Mexico [ab-
stract] ; by Charles T. Kirk 405

Deformation of the coast region of British Columbia [abstract] ;
by Charles H. Clapp 400

Study of ninety thousand pomids of mammoth tusks from Lena

River, Siberia ; by George Frederick Kiinz 407

Excursions 407

Session of Tuesday, August 3

The first session of the Society was called to order at 10 o'clock a. m..
Tuesday, August 3, in the auditorium of Bacon Hall, University of Cali-
fornia, by C. P. Tolman, Jr., Chairman of the Cordilleran Section, in the
absence of President Arthur P. Coleman. Seventy-five members and
visitors were present. After announcements in regard to proposed excur-
sions, the dinner, and the official program, the Chairman declared the
reading of papers to be the regular order.

It was proposed to take up the papers in the order given in the printed
program; those under Topic A, "Erosion and Deposition in Arid Cli-
mates," at the first session, held at the University of California, August
3; thopc under Topic B, "Petrologic Problems of the Pacific Area," at
Stanford University, August 4; and those under Topic C, "Diastrophism

ABSTRACTS AND DISCUSSIONS OF PAPERS 391

of the Pacific Coast," at the University of California, August 5 ; but it
was soon found that absent and tardy members on the list to read papers
would disorganize the program. The program, however, was followed as
closely as circumstances would permit. As carried out, the papers were
presented as follows:

TITLES AND ABSTRACTS OF PAPERS PRESENTED AND DISCUSSIONS THEREON

EPIGENE PROFILES OF THE DESERT
BY ANDREW C. LAWSON

(Abstract)

This paper was a discussion of the development of the characteristic profiles
of the relief of arid regions, with particular reference to the penultimate and
ultimate stages of the processes involved.

Read in full from manuscript.

Discussion

Mr. R. S. HoLWAY : Is there a limit on the Pan- Fan stage, and can it be
readily perceived?

Professor Lawson replied : The limit is reached only occasionally. A change
of climate usually interrupts the Pan-Fan stage and a degradational cycle
ensues.

Prof. Bailey Willis : Instances in China and Patagonia show that the Pan-
Fan stage is rarely reached. Wind erosion is a vital and important agent.
Many agencies that cause modifications have not been indicated in the ideal
Pan-Fan.

Professor Lawson replied that the Great Basin furnished the ideal region
to illustrate instances cited, and that he was inclined to limit his paper to a
consideration of Great Basin features.

BAJADAS OF THE SAXTA CATALINA MOUNTAINS, ARIZONA
BY C. F. TOLMAN, JR.

(Abst7-act)
A description of the composition, structure, and origin of these desert slopes.

Presented in full extemporaneously.

Discussion

Mr. Sidney Paige discussed the use of the term "bajada."

Professor Tolman replied: Bajada, coalescing fan.s that connect the moun-
tain with the holson.

Prof. A. C. liAWsoN oxjtrossed the feoling that the term is superficial and
does not refer to other dimonsions of space.

Professor Tolman replied that bajada should be applied only to the surface
feature.

392 PROCEEDINGS OF THE CALIFORNIA MEETING

ORIGIN OF THE TUFAS OF LAKE LAHONTAN
BY J. C. JONES*

(Aistract)

In the earlier study of the history of Lalie Lahontan, Professor Russell be-
lieved that the tufas were chemical deposits caused by the saturation of the
lake waters with calcium carbonate. A study of the recent tufa forming in
the Salton Sea led to the conclusion that the deposit was due to the activities
of blue-green algie. Carrying the research into the Lahontan Basin, it was
found that the algfe were responsible for the tufa forming at present about
the shores of Pyramid Lake. An examination of the dendritic and lithoid
tufas of Lahontan age disclosed the remnants of algje in the tufa. Other lines
of evidence indicated that the tufa was formed by the algie, the only essential
difference between the lithoid and dendritic types being that the latter was
apparently formed whenever and wherever the conditions of growth were
more favorable for the algse.

Measurements of the more perfect thiuolite crystals showed that they origi-
nally formed as aragonite crystals, and it was discovered that when the water
from Pyramid Lake was saturated with calcium carbonate similar crystals of
aragonite were deposited. It is concluded that the waters of Lake Lahontan
approached saturation with respect to calcium carbonate only at the time that
the thinolite was deposited, and that the history of the ancient lake as written,
based on the origin of its calcareous deposits, will have to be modified.

Discussion of this paper was deferred.

The session adjourned at 12.10 p. m. to convene after the session of
the Paleontological Society.

The Society convened at Bacon Hall, University of California, after
the meeting of the Paleontological Society, 28 members and visitors being
present.

SOME PHYSIOGRAPHIC FEATURES OF BOLSONS
BY HERBERT E. GREGORY

Read in full from manuscript by Prof. C. F. Tolman, Jr.

Discussion

Prof. C. F. ToLMAX, Jr., discussed five types of wind erosion, as follows:
Protected surfaces — (1) by vegetation; (2) coarse gravel and boulders; cites
boulders 1 foot in diameter S miles from mountains, near Tucson, Arizona ;
(3) caliche and surface cements 1 to 6 feet thick; (4) desert pavements —
sheet of pebbles left on wind-swept surface as mosaic; (5) clay in bottom of
playa becomes polished and hardened, protecting from erosion of wind.

Introduced by J. C. Merrlam.

ABSTRACTS AND DISCUSSIONS OF PAPERS 393

Prof. Horace B. Patton : Wind is a transporting rather than abrading agent.

Mr. E. E, Free : Salt crust in desert bolsons is a protection against erosion
bj^ wind.

Prof. Erasmus Haworth : Caliche as protection against wind erosion has
not been given sufficient importance by geologists. (Cites coarse caliche con-
glomerates in western Kansas as "mortar beds."

Mr. J. C. Jones : If erosion by wind is marked, evidence should be shown
in its deposition. Wind does transport, but how much? I am incliued to the
opinion that wind erodes but little.

Prof. Erasmus Haworth : Wind transports sediment to streams and by them
is carried away.

Mr. E. E. Free : Wind transports sediment back and forth, but does not
remove. (Cites oscillating sand-dunes in the Imperial Valley as instance.)

SCULl'TUJiING OF ROCK BY WIND IN THE COLORADO PLATEAU PROVINCE

BY HERBERT E. GREGORY

Read in full from manuscript by Prof. C. F. Tolman, Jr.

Session of Wednesday, August 4

Tlie Society convened at 10.55 o'clock a. m.^, in the Geological Depart-
nimit of Stanford University, Dr. A. C. Lawson acting as Chairman and
J. A. Taff as Secretary.

Seventy-nine meinbers and visitors were present.

titles and ABSTRACTS OF PAPERS PRESENTED AND DISCUSSIONS THEREON

SOME CHEMICAL FACTORS AFFECTING SECONDARY SULPHIDE OIIE

ENRICHMENT

BY S. W. YOUNG »

{Abstract)

An account of some laboratory experiments which have led to artificial
replacement by chalcocite. covellite, and chalcopyrite, and to tlie artificial
disintegration of boniite into calcocite, covellite, and chalcopyrite. all at or-
dinary temperature and under easily attainable conditions: also a discussion
of the probable chemical constitution of bornite and chalcopyrite, together with
some considoriitioiis on the role of the amorphous and colloidal sulphides and
of electro-clu'nii( al phenomena on secondary enrichment. (Experiments, arti-
ficial crystals, etcetera, forty-five minutes.)

Presented in full extemporaneously.

* Introduced by C. V. Tolmau, Jr.

394 PROCEEDINGS OF THE CALIFORNIA MEETING

Discussion

Prof. C. F. ToLMAN, Jr., remarked that hydrogen sulphide is now recognized
as a great mineralizing agent and not a precipitant alone. High temperature
veins carry HjS.

Prof. J. E. Wolff stated the work on sulphides is to be revised.

ROLE OF COLLOIDAL MIGRATION IN ORE DEPOSITS

(Abstract)

As a result of observations made on the action of chalcocite* in becoming
colloidal in mildly alkaline solutions, under the influence of hydrogen sulfide,
and of flocculating or precipitating in contact with calcareous or argillaceous
material, a series of experiments were carried on to see if other sulfides,
arsenides, and sulfo-salt minerals would also change from the massive to the
colloidal condition in alkaline solution, under the influence of hydrogen sulfide.

Experiments showed that nearly all important primary minerals do become
colloidal.

The effect of contact with limestone and alumina on such colloidal solutions
was investigated, and in all cases these materials caused a flocculation of the
colloidal mineral.

The work suggests the possibility of all important primary minerals having
been carried in the ore-bearing solutions as colloids, and that escape of hydro-
gen sulfide or contact with limestone or argillaceous material has caused the
migrating colloids to gather into ore bodies.

Presented in full extemporaneously.

Discussion

Dr. C. S. Bastin suggested that other substances than HjS will play a simi-
lar role in the accumulation of ore deposits. The presence of silica may play
a part in transforming minerals to the colloidal state.

Prof. A- C. Lawson challenged the statement that alkaline solutions come
from magmas.

Mr. J. D. Clark replied that he would establish Ojo Caliente experiments to
show colloidal migration in natural waters.

EXAMPLES OF PROGRESSIVE CHANGE IN THE MINERAL COMPOSITION OF

COPPER ORES

BY C. F. TOLMAN, JR.

{Abst7'act)

This paper was a discussion of the occurrence of high temperature minerals
and of low temperature minerals in the so-called "primary" chalcocite deposits

* Introduced by C. F. Tolman, Jr.

* A chemical study of the enrichment of copper sulfide ores. Bulletin No. 75, Uni-
versity of New Mexico.

ABSTRiVCTS AND DISCUSSIONS OF PAPERS 395

of the Bonanza Mine, Alaska; two-colored chalcocite; meta-colloidal chalcoeite,
and the use of the terms primary and secondary as applied to minerals.

Presented in full extemporaneously.

Discussion

Prof. A. C. Lawson questioned the propriety of such definite conclusions on
interpretations from examinations of ore sections.

8ERICITE, A LOW TEMPERATURE HYDROTHERMAL MINERAL

BY A. F. ROGERS '

(Abstract)

Microscopic study of ores of various types indicate that sericite is a rather
low-temperature mineral formed at or toward the close of the hydrothermal
period. Few, if any, of the hypogene minerals are later than sericite. Sericite
not only replaces quartz and the silicates, but also various sulphides and
sulpho-salts, such as pyrite, chalcopyrite, bornite, chalcoeite, etcetera. The
sericite of metamorphic rocks is also formed at a late stage.

Presented in full extemporaneously. Discussion was deferred.

DINNER

A joint dinner of the Geological, Paleontological, and Seismological
Societies was held at the Engineers' Club, at 7.30 o'clock p. m., about 50
persons participating.

Session of Thursday, August 5

The Society convened at 10.15 o'clock a. m., in Bacon Hall, University
of California, Dr. C. P. Tolniau, Jr., in the chair and J. A. Taff acting
as Secretary.

TITLES AND ABSTRACTS OF PAPERS PRESENTED AND DISCUSSIONS THEREON

I'llYSIOOh'APIIIC CONTROL IN THE PHILIPPINES

BY WARREN D. SMITH

{Ahsiract)

The autlinr i)i-i'sciitc(| m [■Osuiiie of I'liiliiipine geology and tlie resulting
physiographic sectois and a consideration of their effect on the distribution.

* Introduced by C. F. Tolinun, .Ir.

396 PROCEEDINGS OF THE CALIFORNIA MEETING

history, economic life, and probable future movements of various Philippine
tribes. Some comparisons were drawn between Malaysian geology and that
of the west coast of America.

Eead in full from manuscript.

Discussion

Prof. R. A. Daly offered expressions of appreciation and inquiries as to
relations of recent to Tertiary coral reefs.

Professor Smith replied that no break or- disconformity has been noted in
the coral formation of the Philippines.

Prof. A. C. Lawson asked if there are special types of topography in these
regions of excessive rainfall.

Professor Smith called attention to the fact that in Luzon valleys are Y-
shaped and contain no soil.

Further remarks were made by Professors William H. Hobbs and C. F.
Tolman, Jr.

ORIGIN OF THE BASINS WITHIN THE HAMADA OF THE LIBYAN DESERT

BY WILLIAM HERBERT HOBBS

{AT)Stract)

The intense aridity, the nearly uniform wind direction throughout the year,
and the small areas of many of the basins when compared to that of the sur-
rounding hamada are conditions which greatly facilitate a solution of the
problem of origin. In the distribution of the trains of sand-dunes and of the
deposit of loess, reason is found for believing that the basins have resulted
from deflation which has been initiated wherever local faulting has so dis-
turbed the hard mesa capping of Mokattam (Eocene) limestone as to bring the
inferior and soft Cretaceous shales under the influence of the undermining
action of the sand-blast.

Presented in full extemporaneously. Discussion was deferred.

LIMITED EFFECTIVE VERTICAL RANGE OF THE DESERT SAND-BLAST, BASED

ON OBSERVATIONS MADE IN THE LIBYAN DESERT AND IN

THE ANGLO-EGYPTIAN SUDAN

BY WILLIAM HERBERT IIOBBS

(Abstract)

Observations made at numerous localities in northeastern Africa indicate
that the effective action of the desert sand-blast does not there extend to
a height of more than a meter above the surface of the ground. Some expla-
nation for the sharp delimitation of this action was offered.

Presented in full extemporaneously. Discussion was deferred.

ABSTRACTS AND DISCUSSIONS OF PAPERS 397

CHARACTERISTICS OF THE LASSEN PEAK ERUPTIONS OF MAY SO-22, 1915
BY BULIFF S. HOLWAY AND J. S. DILLER

{Abstract)

Lassen Peak, an old volcanic cone, unexpectedly burst into eruption in May,

1914. The most violent explosions came during the period from May 20 to 22,

1915. On the 22d a column of steam and volcanic dust was projected to a
height of at least 30,000 feet above sea, as measured by a nephoscope at lied
Bluff. A localized explosion projected rock fragments over a narrow, fan-
shaped zone extending eastward 10 to 15 miles. Some time during the latter
part of this period of activity the bottom of the crater was pushed bodily
upward, forming a plateau-like top. The eruptions caused floods down Hat
and Lost creeks on the northern slope of the mountain. The initial flood came
down the slope of the main cone with avalanche-like velocity, preceded or
accompanied by a blast which leveled forest trees beyond the flood area.

Presented in full* extemporaneously.

Discussion

Prof. J. S. DiLLER read a brief paper on the recent activity of Lassen Peak.

Mr. R. S. HoLWAY remarked that he had observed the eruption of Mount
Lassen June 1, and that red-hot debris shot up. One red-hot boulder was
seen to roll down from the crest.

Further I'emarks were made by Mr. J. 0. Jones,

The Society then adjourned for lunch.

The Society convened at 3.15 o'clock p. m., with Prof. C. F. Tolman.
Jr., in the chair and J. A. Taff acting as Secretary.

GEOLOGY OF PORTIONS OF WESTERN WASHINGTON
BY CHARLES E- WEAVER

{Abstract)

The oldest formations existing in western Washington are of probable Car-
boniferous, Triassic, and Jurassic ages. They consist of quartzites, cry.stalline
limestones, schists, slates, and a complex assemblage of intrusive and ex-
trusive igneous rocks of pre-Toitiary age. Deposits of Lower Cretaceous are
unknown within the State. The Tipper or Chico Cretaceous occurs in the
northern portion of the I'ugct Sound Basin as an extension of that from the
northwestern side of Vancouver Island.

Presented in full extemporaneously. Kemarks were made by ^Ir. John
P. Bulwada.

398 PROCEEDINGS OF THE CALIFORNIA MEETING

PROBLEM OF THE TEXAS TERTIARY SANDS
BY E. T. DUMBLE

(Abstract)

Five separate sandy formations occur in a comparatively narrow belt in
the Texas coastal Tertiaries. Of these, only one is certainly represented on
the Sabine, while two of entirely different age are present on the Rio Grande.
In the area between these rivers two additional sandstone belts are found,
but so far as known there is no one section in which all five of the sands can
be found. Because of the lithologic resemblance, scarcity of fossils, and lack
of detailed stratigraphic work, much confusion has arisen regarding these beds
and erroneous correlations of them have been made.

The results of recent investigations between the Sabine and Brazos rivers
appear to clear away some of the misunderstandings which have arisen con-
cerning the identity and age of these several beds as they occur in this region,
and to open the road for the final solution of the problem in the areas between
the Brazos and the Rio Grande.

Read in full from manuscript. Remarks were made by Doctors Alex-
ander Deussen and W. D. Matthew.
Published in full in this volume.

PISOLITES AT SAN ANTONIO, TEXAS
BY ALEXANDER DEUSSEN '

(Abstract)

A description of pisolitic pebbles in stream terraces of San Antonio River
was given, with a discussion as to the possible origin of the pebbles. A map
showing the location and photographs illustrating sections of the pisolites
were exhibited.

Presented in full extemporaneously. Remarks were made by Dr. W. D.
Matthew and Messrs. Bruce L. Clark and H. W. Turner,

GEOLOGIC AGE OP THE COAL CREEK BATHOLITH AND ITS BEARING ON SOME
OTHER FEATURES OF THE GEOLOGY OF THE COLORADO FRONT RANGE

BY HYRUM SCHNEIDER'

(Abstract)

The name Coal Creek batholith is here given to a mass of granite exposed
in parts of Gilpin, Jefferson, and Boulder counties, Colorado. This granite
has heretofore been considered as pre-Cambrian and probably Archean.

In mapping the Coal Creek quartzite, what appears to be good field evidence

« Introduced by J. A. Taff.
"> Introduced by H. B. Patton.

ABSTRACTS AND DISCUSSIONS OF PAPERS 399

has been found showing that the granite is post-Algonkian, and probably post-
Peunsylvaniau, in age.

The probable Mesozoic age of the granite simplifies the interpretation of
the structure of the Coal Creek quartzite and does away with the necessity
of faulting to explain the relation of the igneous to the sedimentary rocks in
the vicinity of the South Boulder peaks.

The lithology and structural relations of the granite suggest a thick covering
of sediments at the time of its intrusion, which throws additional light on
this part of the front range as a positive block in the earth's crust.

Presented in full extemporaneously.

Discussion

Prof. Erasmus Haworth asked if there are fragments of granite in quart-
zite.

Mr. Schneider replied that the granite is not gneissoid ; that it shows no
indication of crushing, and the quartzite pebbles are mashed and elongated.

Further remarks were made by Prof. H. B. Patton and Dr. E. S.
Bastin.

OCCURRENCE OF FLOW-BRECCIAS IN COLORADO

BY HORACE B. PATTON

{Al)St7'aCt)

That igneous magmas intruded through and into the overlying rock forma-
tions are prone to pick up and incorporate fragments of all kinds and sizes
on their way to and over the surface is, of course, no recently recognized
phenomenon. The occurrence of such foreign inclosures has long been recog-
nized as one of the common features of volcanic action. It would seem, how-
ever, that sufficient emphasis has not been laid on this subject by most investi-
gators of igneous phenomena, and that the extent and frequency with which
such rocks occur has not met with wide recognition.

In his investigation of the very extensive volcanic series of the San Juan
Mountains in Colorado, Whitman Cross some twenty years ago observed some
striking instances of igneous rocks in the form of dikes and sheets picking
up fragments of the country rocks through which they broke their way to the
surface and was the first to apply to such occurrences the name flow-breccia.'
In his description of the rhyolites of the Intermediate Series and of the Potosi
Rhyolite Series of the Telluride quadrangle. Cross describes in some detail the
occurrence of these flow-breccias and finds them often difficult to distinguish
in the field from true breccias and tuffs. For instance, of the rhyolites of the
Intermediate Series he says that they consist in part of "apparent tuffs of
rather indistinct character, many of which wore found to be flow-breccia —
that is, a rhyolite flow lu)lding so many fi'Mgnients of andesite that tlie fluidal
matrix becomes (juite inconspicuous and can not be seen with the naked eye.

MVhltman Cross: I'. S. Oc<)li>Ki<"il Survey Vo\U> No. 57. 1800.

400 PROCEEDINGS OF THE CALIFORNIA MEETING

The true nature of these rocks was not recognized in the field, and, indeed, the
base of the series was not determined for many localities until the specimens
were microscopically studied."

Flow structure seems to be especially characteristic of portions of the Potosi
Rhyolite Series, and in this case the inclosed fragments are partly andesitic,
but mainly rhyolite, similar to that of the massive flow. Of this Cross says :
"The fragmeutal character is most evident near the bottom of the band, and in
several sections a massive flow with many inclusions — a flow-breccia — follows
without any clearly defined line of separation ; in fact, some specimens col-
lected to represent gravelly tuff were found on microscopical examination to
be flow-breccia."

Other flow-breccias have later been described by Cross as occurring in the
San Juan Mountains. Some of these contain fragments like the fluidal ma-
trix; others like that of the Intermediate Series of the Telluride (luadrangle,
fragments different from such matrix. This is notably true of a flow-breccia
in the Silverton quadrangle, to which the name Eureka rhyolite has been
given. Of this rock Cross saj's :" "The second member of the Silverton Series
is a rock belonging to the most siliceous of the magmas, which were erupted
during this epoch of the San Juan volcanic history. It is so characterized by
small included fragments of andesites, of rocks very similar to the rhyolite
itself, or occasionally of granite, schist, etcetera, and has so commonly a flow
structure that much of the rock may be called a flow-breccia. . . . Nor-
mally it is a grayish rock exhibiting many small angular inclusions, averag-
ing much less than half an inch in diameter, of dark, fine-grained andesites or
of reddish or grayish rhyolite, and has a prominent fluidal texture in the
dense felsitic ground-mass which holds the fragments."

A flow-breccia has also been described by Crawford^" as occurring on Brittle
Silver Mountain, in the Monarch-Tomichi district. Here, again, we have a
flow-breccia that contains fragments of porphyry not identical with the ma-
terial composing the lava flow in which they are inclosed.

A flow-breccia, then, according to the definition established by Cross, may be
considered to be a rock having an outward resemblance to a true breccia, of
which the cementing material is a fluidal massive lava and the inclosed frag-
ments similar to or different from the fluidal matrix.

Such flow-breccias are, according to the observations of the writer, of very
great frequency, not only in the San Juan Mountains, but in the outer lying
extension of the San Juan volcanic series to the east and north and also in
other parts of Colorado.

In Saguache County, for insti^nce, in the Bonanza district, is a very marked
case of a latite surface flow stretching for a distance of at least 12 miles, in
every part of which fragments of inclosed andesite may be observed, in some
parts so thick as to closely resemble a true breccia. In the Platora-Summit-
ville district, in Conejos County, some 50 or 60 miles southeast of the San
Juan Mountains, occurs a flow-breccia very similar to some of those of the
Potosi Series; and in another part of this same district was observed mon-
zonite porphyry with inclosed fragments of monzonite.

Again, in the Bonanza district, there occurs a rock closely resembling a

» U. S. Geological Survey Folio No. 120, 1905, p. 7.

10 R. D. Crawford : Colo. Geological Survey Bull. No. 4, 1913, p. 176.

ABSTRACTS AND DISCUSSIONS OF PArERS 401

breccia, consisting of amphibolite, that is probably a metamorpliosed diorite,
inclosed in a matrix of very similar character.

In the Alma district, in the Mosquito Range, an intrusive mass of diorite
occurs imbedded in a matrix that is almost identical with the fragments.

In attempting to describe these occurrences, in which the structures desig-
nated as flow-breccias are a characteristic feature, the writer has felt the need
of a descriptive term that may l>e used without reference to the exact nature
of the inclosed fragments of the enveloping fluidal matrix, and would venture
to suggest the term rhyoclastic as suitable for this purpose.

A rhyoclastic rock, then, would be an igneous rock in which occur numerous
inclusions of fragments of similar or of different material, so as to resemble
more or less closely a true breccia.

Unfortunately, the term flow-breccia has been employed by Iddings in a
quite different sense from that originally given by Cross. In his book on
Igneous Rocks. Iddings" writes as follows : "When exploded fragments of
molten magma, large or small, fall together in a still heated condition, as may
readily happen within the crater of a volcano or the mouth of a fissure, they
may be plastic enough to weld together in a more or less compact, coherent
mass. This may subsequently flow like other lava, and is known as flow-
breccia."

While such a rock may, of course, very properly be called a flow-breccia, it
does not seem to he wise or in conformity with well established custom to
change the definition as originally given by Cross. And yet it would be well
to recognize the structure to which Iddings has applied this term. This could
be done and confusion avoided by designating such rocks as welded flow-
breccias.

We have, then, two types of flow-breccias : a rhyoclastic flow-breccia, where
foreign fragments are caught up in great abundance in a flowing igneous
matrix, and a welded flow-breccia, where fragments of a partially plastic
igneous magma are shattered by some explosive act and flow together again
b.\- a process of welding.

Presented in full extemporaneously.

Discussion

Prof. Erasmus Hawortu expressed a desire for further information on flow-
breccias and as to how this breccia is distinguished from other types of breccia.

OEOLOOY OP A PORTION OF THE SANTA YNEZ RIVER DISTRICT, SANTA

BARBARA COUyTV, CAIJFORXJA

(Ahstrarf)

Tlic region under discussion cniliraccs the Santa Ync/. Mountains east of the
San Marcos I'ass, the Santa Ynez River Canyon, and the mountains lying im-

" J. V. IddliiKs : iKticons Kocks, vol. iV V.to;), p. ;;.;i.
*^ Introduced by A. C. Lawson.

402 PROCEEDINGS OF THE CALIFORNIA MEETING

mediately to the north. The following groups and zones are represented :
The Franciscan, Knoxville, Chico(?), Tejon, Vaqueros (Turrltella inezana
zone), Temblor (Turritella ocoyana zone), Monterey shales, Fernando, and
Pleistocene terrace deposits. Two thrust-faults are the main structural fea-
tures north of the Santa Ynez Mountains. An anticline which shows more
intense deformation in its eastern part forms the Santa Ynez Mountains.

Kead in full from maniiscript. Discussion was deferred.

INTERESTING CHANGES IN THE COMPOSITION OF THE SALTON SEA

BY A. E. VINSON ^

{Abstract)

This paper discussed the change in composition of the waters of the Salton
Sea developed by progressive evaporation.

Presented in full extemporaneously. Discussion was deferred.

EXAMPLES OF SUCCESSIVE REPLACEMENT OF EARLIER SULPHIDE MINERALS
BY LATER SULPHIDES AT BUTTE, MONTANA

BY J. C. bay"

(Abstract)

The ore deposits at Butte, Montana, belong to the replacement type. They
include three distinct sets of ore minerals arranged zonally. These zones
grade into each other and the divisions must be made arbitrarily. They are ;

First. Silver zone. Silver, lead, and zinc minerals predominating.

Second. Zinc zone. Sphalerite predominating.

Third. Central or copper zone. A complex series of copper minerals.

This paper deals more particularly with successive and selective replace-
ment of earlier sulphides by later sulphides in the copper zone and the inner
border of the zinc zone.

The importance of this type of replacement has, perhaps, not been fully
appreciated by students of ore deposits, and the present paper presents a few
examples of this process which the writer has termed progressive enrichment.

The mineral sequence as determined for the Butte district is as follows :

1. Period. Quartz-pyrite. Replacement of quartz-monzite

Pyrite-quartz. along fractures.

2. Period. Sphalerite. Chalcopyrite.

Galena.

Silver sulphides.

3. Period. Tetrahedrite. Chalcopyrite.

Enargite. Bornite ?

Tennantite.

13 Introduced by C. F. Tolman, Jr.
" Introduced bv C. F. Tolman, Jr.

ABSTRACTS AND DISCUSSIONS OF PAPERS 403

4. Period. Bornite. Chalcopyrite.

Covellite. Bornite.

Chalcoeite.

5. Period. Chalcoeite.

Those ill the second column are the minerals of any one period, while the
minerals in the third column are of secondary importance as ores, but of great
interest from a scientific point of view.

Presented in full extemporaneously.

Discussion

Then followed general discussion of all papers bearing on ore deposition.

Prof. A. F. Rogers gave a full summary of the evidence on the temperature
of the formation of sericite.

Mr. Sidney Paige questioned whether sericite is not a low-temperature min-
eral and the result of weathering.

Professor Rogers gave reasons for believing that sericite is the result of
hydrothermal alteration and not of weathering.

Dr. E. S. Bastin gave an appreciation of the work being done at Stanford
University on ore deposits.

Prof. C. F. ToLMAN, Jr., called attention to the complex relation discovered
by the metallographic examinations of ores and the care that should be used
in interpreting these.

STRUCTURE OF THE SOUTHERN SIERRA NEVADA
BY JOHN P. bulwada"

(Abstract)

The rocks of the southern Sierra Nevada may be grouped into two divisions,
as are those of the central and northern Sierra: a basement complex consist-
ing of pre-Cretaceous intrusive rocks and metamorphosed stratified forma-
tions intensely deformed, and a superjacent series, made up of igneous and
sedimentary rocks but little deformed and lying with marked unconformity
upon the basement complex.

The structure of the few remnants of stratified rocks in the basement com-
plex of the southern Sierra corresponds to that of the pre-Cretaceous rocks in
the more northerly portions of the range; the strata dip steeply and usually
strike approximately north-south. The structure of the rocks of the super-
jacent series in the southern Sierra differs markedly from that in the central
and northern Sierra. Instead of lying nearly flat, they have been folded along
both the northwestern or San .loaquin Valley side and the southeastern or Mo-
jave Desert liordcr of the range, as well as in the summit region. The struc-
ture of the Siena thus comes to resemble that of the Coast Ranges somewhat
as the Sierran range approjiches the coast;il mountains.

Tiie great fault zone which l)ord(>rs the central and northern Sierra on the
east continut's along the southeastern face of the southern Sierra to the Coast
Ranges.

"* Introduced by A. C. I.awson.

404 PEOCEEDINGS OF THE CALIFORNIA MEETING

Eead in full from manuscript. Remarks were made by Messrs. E. T.
Chamberlin, R. S. Holway, and C. F. Tolman, Jr.

A MEASURE OF ARID EROSION
BY CHARLES KEYES

{Ahst7-act)

The arid regions of western America are particularly noteworthy because
of the fact that throughout their extent there have been during late geologic
times prodigious extravasation of lavas. These outpourings of basaltic mag-
mas continued, without luiTisual interruptions, from the early Tertiary period
to the present epoch. Being largely extruded over soft deposits of great thick-
ness and wide extent, both lava streams and lava fields resist in a remarkable
way all erosive influences. In the erosion and the general lowering of the
country the areas covered by the lava-sheets soon develop into plains which
now are elevated greater or less distances above the surrounding general
plains surface. These plateau plains constitute one of the most characteristic
features of arid landscapes.

With the geologic age of the underlying rocks and the time of the lava
flowing determined, a measure is provided, within very narrow limits of error,
for the time elapsed between the appearance of the effusive cap of the plateau
plain, when this level was the general plains surface, and the formation of the
present plains surface. There are many svich plateau plains on the northern
end of the Mexican tableland. In this connection one in particular deserves
especial mention. The level of the great Mesa de Maya, in northeastern New
Mexico, now 4,000 feet below the crest of the adjoining Rocky Mountains, is
3,000 feet above the next lower plain, the Ocate plateau, which latter is 500
feet above the broad Las Yegas plain, now constituting the general plains
surface of the region. Into the surface of the latter the Canadian River in-
trenche.s itself to a depth of 2,000 feet.

"Under conditions of an arid climate, where water action is almost unknown,
the erosive power is believed to be mainly the winds.

Presented by title in the absence of the author.

A POSSIBLE CAUSAL MECHANISM FOR HEAVE FAULT-SLIPPING IN THE
CALIFORNIA COAST RANGE REGION

BY HARRY O. WOOD "

(Abstract)

The causal mechanism proposed is differential creep of a subcrustal layer,
with a maximum movement in the direction of the trend of the Coast Ranges
and a minimum transverse to this trend due to lightening of the mountain
belts and loading of the valleys and the sea-floor offshore. The principal point
in the paper is the hypothesis which explains the causal relation between this
transfer of load and the differential creep.

Presented by title in the absence of the author.

" Introduced by A. C. Lawson.

ABSTRACTS AND DISCUSSIONS OF PAPERS 405

STRUCTURAL FEATURES OF THE TSfN LI^IG l^HA Y
BY GEO. D. LOUDERBACK

(Abstract)

This paper includes notes on sections observed; comparison witii routes of
former expeditions. The inner zone ; crystalline complex, development of iso-
clinal folds; general effects of granitic intrusion. The Mesozoic overlap. The
southern zone of thrust. Late Mesozoic or early Tertiary faulting. Late Ter-
tiary or Quaternary faulting. Structural relations of the loess. Rt'.sume of
the recognized diastrophic history taken as characteristic of central China,
and general comparisons with the diastrophic history of the Pacific States of
America. General comparison of results with those of earlier expeditions.

Presented by title in the absence of the author.

CERTAIX STRUCTURAL FEATURES IN THE COAL FIELDS OF yEW MEXICO

BY CHARLES T. KIRK "

(Abstract)

In the Number 4 Anthracite mine at Madrid, New Mexico (Upper Mesa-
verde), there occurs a thrust-fault of northerly strike with the astonishingly
steep dip of generally 85 degrees westerly, the upthrow being on the west side.
Within a thousand feet of where this fault is best exposed in the woi-kings is
another somewhat local normal fault of northwesterly strike with the aston-
ishingly flat dip of generally only 6 degrees southwesterly, the upthrow l>eing
Du the northeast .side. The country flanks on the Ortiz Mountains and is fur-
ther affected by sills and perhaps other igneous bodies. Surface agencies have
so altered the outcrops of these faults — if they ever appeared at the surface —
that they may not now be studied there; but workings have progressed suffi-
ciently to warrant an explanation of the former by suppo.sing a radial lift,
probably during intrusion, and i)f the latter by a tangential stretch, probably
during cooling of the same or a neighboring magma. The .strata and sills dip
14 degrees easterly in both cases, .so that the faults act as artesian chainiels.
and both bring up nuich incombustible gas, presumably carbon dioxide, and
some combustible gas, apiiarently cai'bon monoxide, both probably from car-
bonaceous beds below. The first was cut inexpensively by noting that the
(igneous) roof rock is underthrust in the face of the entry; the second re-
vealed its hidden nature only by bits of drag.

In the Heaton mine at (Jil)son (dallup District), New Mexico, is a fault
cutting the Number 5 coal bed (Upper Mesaverde) and offsetting it l.'4 feet
vertically ; yet 00 feet above the Number 3 bed, which has l)een worked out
over the entire area of the vertical fault mentioned, .shows no trace of a break.
While this is suggestive of :i disconfoi luity, no s)n'fa<-e corroborations of such
an hiatus are .vet discov crcMl.

The occurrence of tlic last pai :igr:ii)li is recalled wlieii one examines a break
in the Upper Me.saverde coal at Uogers, near Cerillos, .\ew Mexico. The upper

" Inf rod'iced by C. K. I-cllli.

XXXII— Blt.i,. Geol. See. Am., Vol. 26, 1014

406 PROCEEDINGS OF THE CALIFORNIA MEETING

bed of the series here runs from the south about 3 feet high, genei-ally under
a sandstone roof, to a locality nearly over the Waldo mine, where it is cut
away locally to only a few inches. This instance has been cited as evidence
that here is the division between Cretaceous and Tertiary in the region dis-
cussed.* It would seem desiral)le, however, that there be found more definite
evidence of at least more quantitative importance for designating an oral
unconformity than a soft member under a clastic formation deposited appar-
ently under locally turbulent conditions. In a country and at a geologic age
where so many unusual geologic features — such as have been cited above —
are prevalent, only extremely close scrutiny of every obtainable evidence has
brought the writer reliable results.

DEFORMATIOS OF THE COAST liEOlON OF BRIThSn COLUMBIA

BY CHARLES H. CLAPP

(Abstract)

The first period of deformation recorded in the exposed formations of the
coast region of British Columbia, by which term is meant that portion of
British Columbia which lies to the west of the main crest of the Coast Range,
presumably oct-urred at or near the close of the Paleozoic. Although the char-
acter and degree of deformation oci-urring at that time has l)een almost en-
tirely obscured by later, more intensive deformation and by batholithic intru-
.sion. there is some evidence that the folding was of an open character, with
the principal axes of folding at a considerable angle to the present prevailing
northwest-southeast trend of the rocks of the region.

The principal period of deformation, as is true of the entire Pacific Coast
region, took place near the close of the Juras.sic. This period of deformation
can not be dated closely from the known date of the coast region of British
Columbia, since the oldest unaffected rocks are of Upper Cretaceous age and
rest unconformably on unroofed batholiths intruded during and following the
deformation.

Lower Cretaceous rocks are not found, although they liave been supposed to
occur on Queen Charlotte Islands. It was during this period of deformation
that most of the rocks of the region attained their general northwest-southeast
trend. The folding occurred in the zone of combined fracture and flow, so the
weaker rocks were deformed to closed folds of the similar type, while the
more competent rocks were deformed into parallel folds of a more open char-
acter. Batholithic intrusion took place during this deformation, producing
primary gneisses, although later batholiths appear to have been intruded after
most, if not all, dynamic movement had ceased.

Portions of the coast i-egion were profoinidly affected by the next period of
deformation, which does not appear to have taken place luitil the close of the
Eocene. The rocks were warped into rather broad folds, whose general north-
east-southwest axes were determined by the l)uttresses of older and more com-
petent rocks. Extensive faulting, also, largely of a reversed or overthrust
character, took place at this time and in places stocks of subjacent rocks were
inti'uded.

U. S. Geological Survey Bull. 531.1, l'Ji:5, p. lo.

ABSTRACTS AND DISCUSSIONS OF PAPERS 407

No extensive faultiug or folding has occurred since the post-Eocene period
of deformation, although uplift and some tilting has taken place. The most
conspicuous uplift, presumahly during Pliocene times, was followed by at least
local depression, and since Glacial times there has been a very general uplift
of from 250 to 600 feet.

Presented by title in the absence of the author.

STUDY OF yiXETY THOl'SAXD POUNDS OF MAMMOTH TUSKS FROM LENA

RIVER, SIBERIA

BY GEORGE F. KUNZ

Presented by title in the absence of the author.
The Society then adjourned sine die.

EXCURSIONS

On Thursday, Aug-ust 5, an excursion, in charge of A. C. Lawson, of
the University of California, was made to Hunter^s Point to see a contact
of variolitic and ellipsoidal basalt, intrusive in radiolarian cherts of the
Franciscan, and incidentally the intrusive relations of serpentinized
peridotite to the Franciscan.

On Friday, Augiist 6, an excursion, in charge of A. C. Lawson and
E. P. Davis, of the University of California, was made to San Andreas
fault and rift. Point Reyes Station, Marin County, to see the most pro-
nounced phenomena of the horizontal slip on the San Andreas fault ;
also the rift topography.

On Saturday, August 7, an excursion, in charge of E. S. Holway, of
the University of California, v/as made to the Santa Cruz Ocean beaches
to see the finely preserved series of old ocean beach terraces which occur
u]) to 1.200 feet ahove present sealevel. The three major terraces are
broad, the maximum width of the lowest terrace being one mile. Fifteen
to twenty terraces arc found in ]ilnces between Santa Cruz and Daven-
port, 12 miles westward.

On Monday, August 9, an excursion, in charge of A. C. Lawson and B. L.
Clai-k, of the University of California, was marie from Berkeley to Mount
Diablo. This ti'ip enabled tlie excursionists to s^ee a fairly complete
section of the strata imolved by the great geosynclino which lies between
tlx' valley of tlie r)ay of San Francisco and ^Mount Diablo. The lowest
' strata of the section, the Franciscan, are exposed on the two flanks of the
geosyiieline. Resting on the Franciscnn in ascending order are the Knox-
ville shales, the Oakland conglomerate, and Chico s^andstone and shale.
extending from Tiower to T^titter Cretaceous. The Tertiarv formations

408 PROCEEDINGS OF THE CALIFORNIA MEETING

resting on the Chico comprise (1) the Martinez and Tejon, two local
(li\ isioiis of the Eocene; (2) the Monterey (Miocene) group, comprising
altci-iiatc formations of sandstones and l)itnminoiis shales, some of which
are cliiTls: ( :! ) the San I'ablo formation, and (4) fresh-water Ijeds of the
Oriiidaii forination in the middle of the syncline. »Still later than the
Orindaii. on the western side of the syncline, is a belt of alternating lavas
and laeustral and tliiviatile deposits, which are best exposed on the hill-
tops immediately back of the University of California. These strata are
crossed in the h'ne of tbe route of this excursion.

On Tuesday, August 10, a trip to the Yosemite Valley was begun,
under the charge of J. A. Taif, Acting Secretary of the Society, and F. C.
Calkins, of the United States Geological Survey. This trip occupied
seven days. After examining the park, the members became the guests
of the Sierra Clul). ^^■hich had all the conveniences for mountain trans-
portation and subsistence, and conducted the party up Tenaya Canyon
via Mirror and Tenaya lakes to the Sierra Club's main camp at Tuolumne
Meadows — a day's journey. Opportunity was given iov an examination
of tlie unusual glacial effects exposed in the Tuolumne Meadows locality.
From this camp excursions were nuide to study the glacial and other
geology in the canyons and higli Sierras.

Ei:(;isTEii OF Tin-: Califohxia MF:ETixf;. ini.";

Ealph Arnold John C. Meruiam

Edson S. Bastin Henry F. Osborn

Edward W. Berry Sidney Paige

John C. Braxxei; Horace B. Patton^

EoLLix' T. Chamberlix^ Charles Schuchert

Charles H. Clapp Elias H. Sellards

Eegixald a. Daly William J. Sixclair

Arthur L. Day W. S. Taxgieu Smith

Joseph S. Dillei; Timothy W. Stantox"

Edwix^ T. Bumble Ealph Vr. Stox'e

Harold W. Fairbaxks Joseph A. Taff

Erasmus Haavortfi Cyrus F. Tolmax', Jr.

Oscar H. Hershfy Hexry W. Turxer

William H. Hobbs Edward 0. Ulrich

Charles Keyes Charles E. Weaver

Ax^DREw C. Lawsox Israel C. White

W. T). Matthew Bailey Willis

John E. Wolff

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA
Vol. 26, pp. 409-418 November 23, 1915

PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

PEOCEEDINGS OF THE SUMMER MEETING OF THE PALE-
ONTOLOGICAL SOCIETY, HELD AT THE UNIVERSITY
OF CALIFORNIA AND AT STANFORD UNIVERSITY, AU-
GUST 3, 4, 5, AND 6, 1915.1

Chest ef; Stock, Secretari/ /ini Inn.

CONTENTS

Page
Session of Tuesday, August 3 410

Criteria of correlatiou from tlie poiut of view of tlie invertebrate

paleontologist ; by P]dv/ard O. Ulricli 410

Problem of correlation by use of vertebrates; by William D.

Matthew 411

Cox'relation and chronology on the liasis of paleograitliy : by

Charles Schuchert 411

Discussion of the preceding three papeis 411

Session of Wednesday, August 4 412

Relations of the invertebrate faunas of the American Triassic to

tliose of Asia and Europe [discussion] ; by James I'errin Smitli. 412

Triassic deposits of Japan [discussion] ; by H. Yabe 413

Correlation between the terrestrial Trias-sic forms of western

North America and Europe [discus.sion] ; by Ricliard S. Lull... 413
Comparison of marine vertebrates of western North America

with those of other Triassic areas: l>y John C. Merri.iiii 413

Dinner 413

Session of Thursday, August 5 413

Correlation between tlie Cretaceous of tlie I'acilic ariM ;;ih1 that

of otlier regions of tlie world; by Timotliy W. Stanton 414

Correlation of the Cretaceous invertc1)r,itc faunas of Califoi-nla ;

by Timothy W. Stantcm 414

Correlation between invertebrate faunas of California and tliose

of Mexico ; by Earl L. Packard 414

Comi»iirison of the Cretaceous famias of .laiciii with tliose of

western United States ; l)y H. Yabe 414

Comparison of tlie Cretaceous floras of California with tliose of

otlier Cretaceous aicas; by F. II. Ivnowlton Ill

Discussion of tho iircccding livf papers 414

'^ MaiHiscripl i-cccivi'(l liy the Secretary of tlio (!eol<>Kical Society <ir .\merica October
30, 1915.

(409)

410 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

Page
Session of Friday. A iiLrust 6 415

Intro<luptoi-.\- remarlvs on coi'rolation of ^Miocene: by Henry Fair-
field O.sborn 4I5

Correlation of the Lower Miocene of California ; l>y Ralph Arnold. 415

Review of the Miocene and Oligocene favnias of California ; by
B. L. Clark ... 416

Miocene of the Washington-Oregon province and its relation to
that of California and other Pliocene areas; by Charles E.
Weaver 416

Vertebrate faunas of the Pacific coast region ; by John C. Mer-
riam 416

Correlation between the Middle and late Tertiary of the South
Atlantic coast of the United States with that of the Pacific
coast ; l)y E. H. Sellards 416

Relation of the Miocene mammalian faunas of western United
States to those of Europe and Asia; by William D. Matthew.. 416

Correlation of the Miocene floras of western United States v/ith
those of other jNIiocene areas ; by F. H. Knowlton 416

Flora of Florissant ; by T. D. A. Cockerell , 416

Faunal geography of the Eocene of California ; by R. E. Dickerson 416

Recent work on the dinosaurs of the Cretaceous ; by Henry Fair-
field Osborn 416

History of the Aplodontia group : hy W. I*. Taylor 417

Some problems encountered in the study of fossil birds of the

west coast ; by L. H. :Miller 417

Resolution of thanks 417

Excursions 417

Session of Tuesday, AuCxUst 3

The meeting was called to order by Dr. Edward 0. Ulrich, the Presi-
dent of the Society, at 2 o'clock, in Bacon Hall, room 20G, University of
California. Doctor Ulrich then requested Prof. J. C. Merriam, Vice-
President, to take the chair. Professor Merriam, after welcoming the
visiting paleontologists, pointed out the value of a discussion of correla-
tion problems involving the areas both east and west of the Cordilleras
and on both sides of the Pacific Ocean. The subject of the meeting,
"General consideration of Paleontologic criteria used in determining
time relations,'" was then declared in order and the following papers were
presented :

CRITERIA OF CORRELATION FROM THE POINT OF VIEW OF THE
INVERTEBRATE PALEONTOLOGIST

BY EDWABD O. ULRICH

ABSTRACTS AND DISCUSSIONS OF PAPERS 411

PROBLEM OF CORRELATION BY USSE OF VERTEBRATES
BY WILLIAM D. MATTHEW

CORRELATION AND CHRONOLOGY ON THE BASIS OF PALEOGRAPHY

UY CHARLES SCHUCHERT

On account of the absence of Dr. F. H. Knowlton, the reading of his
paper, entitled "Correlation based on a study of tlie history of plants,"
was postponed to a later meeting.

Discussion of the preceding three Papers

Doctor Matthew stated that the ultimate displacement of straud-lines is
satisfactory for wide-spread movements, but in a practical application it is
doubtful whether such movements are in unison.

Prof. J. P. Smith stated that in the case of the Triassic rocks of the West
correlation has l)een purely by paleontology.

In correlating the Lower Cretaceous strata, Dr. T. W. Stanton stated that
paleontology alone has been used. It was conceded that for practical purposes
correlation is by paleontology, but that ultimate correlation depends on dias-
trophism.

Professor Schuchert bi'iefly reviewed Suess' conception of the great overlap
in the Cretaceous and his application of this principle to the Devonian, and
considered the Pacific province in this connection. He called attention to the
fact that the middle of a period is characterized by the most <-osmopolitan
fauna.

Professor Osborn called attention to the importance of fossils as compared
with diastrophic movements when used for correlation purposes, and empha-
sized the stability of protoplasm thi-ough the past as r-onti-astod with our
standards of permanence in the inorganic world.

Professor Willis called attention to the insufficiency of our knowledge con-
cerning diastrophism. He contrasted the gradual changes in the Mississippi
liashi with the su<lden changes on the Pacific coast, and questioned the univer-
sality of movements. The .Vtlantic and the I'acilic are separate dynaniic basins
which are discordant in their movements. It is necessary to \v()rk out the
paleogeography in as great dctiiil -Jis i)ossible.

Doctor Ulkich remarked that in consid<>ring diastrophism we should note
especially tlio.se movements felt over broad areas. lie believed in the correla-
tit)n of submergence in one region with emergence in aiidtbcr.

Professor Mekriam in summarizing stated that the present discussion was a
necessary preliuiinary to any consideration of correlation between the Pacific
and Atlantic basins. He noted that the consensus of opinion seenied to be that
organic criteria fiuTiish the tools actually nst-d in practicall.\ all wide-range
correlation. Att(iiti<Mi w.is directed to the importance of the liistory of life
as a basis or scale U>v use in lime nieasiu'emeiit or classification.

Tlie meeting tlien adjourned.

412 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

Session of Wednesday, August 4

The meeting was called to order by Prof. J. P. Smith at 2.30 o'clock,
ill room 320, Department of Geology, Stanford University. Prof. J. C.
Merriam was then called to the chair. The symposium, "Correlation of
the Triassic," formed the topic for this meeting, and four following
papers on this subject were presented :

RELATIONS OF THE INVERTEBRATE FAUNAS OF THE AMERICAN TRIASSIC

to those of asia and europe

by james perrin smith

Discussion

In answ^er to a query by Professor Merriam as to the number of species
occurring in the Triassic of California, Professor Smith replied that a con-
servative estimate would place the number at about 400. He stated that the
number of interregional faunas were three in the Lower, two In the Middle,
and four in the Upper Triassic. These are separated by local faunas. In
Europe definite faunal zones can be recognized, and between these are beds
not characteristically fossil if erous, or in some cases non-fossiliferous.

In reply to Professor Merriam's (luery as to whether these interregional
faunas were more or less common in the Triassic than in later periods. Pro-
fessor Smith replied that they were much more common in the Triassic.

Professor Schuchert emphasized the cosmopolitan range of ammonites,
their extensive migration, and stated that there was nothing comparable among
the other groups of invertebrates.

Professor Smith stated that the ammonites were apparently exceedingly
sensitive to changes in their diet. They appear to be represented about coral
reefs and are not foiuid in black shales.

Doctor Ulrich pointed out various aspects of the migration problem. He
stated that species may pass around rather than across basins, and that forms
do not always choose the shortest way across.

After noting the pro])ortions of ammonites, pelecypods, brachiopods, and
other invertebrates in the Triassic faunas. Professor Schuchert remarked
that with the exception of the ammonites the types are all shallow-water
forms. Ammonites were powerful swimmers and probably did not float. Dur-
ing the development of geosynclines the ammonites lived in relatively shallow
waters.

I'rof. J. C. Jones pointed out that in discussing the migration of these forms
it is necessary to consider also the course of oceanic currents.

In answer to Professor Merriam's query whether the number of interre-
gional zones denoted a great length of time. Professor Smith replied that it
certainly implied a number of physiographic changes in the Triassic. He
stated further that he did not believe that climatic changes exerted a great
influence on the general evolution of these forms.

ABSTKACTS AND DISCUSSIONS OF PAPERS 413

Professor Schuchekt expressed his appreciation of I'rofessor Smith's work
in elucidating the Triassic problems of North America.

TRIASSIC DEPOSITS OF JAPAN
BY H. YABE

Discussion

Professor Smith stated that the Middle Triassic is represented in Japan.
In commenting on the fauna, he noted the differences exhibited by the ammon-
ites and the similarity of the other forms when contrasted with North Amer-
ican types. He designated the differences as provincial.

CORRELATION BETWEEN THE TERRESTRIAL TRIASSIC FORMS OF WESTERN

NORTH AMERICA AND EUROPE

BY RICHARD S. LULL

Eead by Charles Sclmchert.

Discussion

Professor Merriam noted the inherent difficulties in correlating continental
with marine formations, since land vertebrates occur, as a rule, where there
are no marine deposits.

Professor Smith remarked that a case in point is shown on the border be-
tween Idaho and Utah, where the land and marine Triassic are 15 miles apart
and yet it is impossible to correlate across.

COMPARISON or MARINE VERTEBRATES OF WESTERN NORTH AMERICA
WITH THOSE OF OTHER TRIASSIC AREAS

BY JOHN C. MERRIAM

The meeting then adjourned.

DINNER

On Wednesday evening tlio momlters of the Society joined with the
Geological Society in a diiuici' gi\cn at tlic l^ngineers' Cluh. in San Fran-
cisco.

Skssiox ok TiintsDAY, August o

This meeting of the Society was called to order by Dr. Timotby W.
Stanton at 2.'M) o'clock, in liacon Hall, room 20(5, University of C'alit'or-

414 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

nia. The symposium, "Correlation of the Cretaceous," formed the topic
of this meeting- and the following papers were presented :

CORRELATION BETWEEN THE CRETACEOUS OF THE PACIFIC AREA AND
THAT OF OTHER REGIONS OF THE WORLD

BY TIMOTHY W. STANTON "

CORRELATION OF THE CRETACEOUS INVERTEBRATE FAUNAS OF CALIFORNIA

BY TIMOTHY W. STANTON

CORRELATION BETWEEN INVERTEBRATE FAUNAS OF CALIFORNIA AND

THOSE OF MEXICO

BY EARL L. PACKARD

COMPARISON OF THE CRETACEOUS FAUNAS OF JAPAN WITH THOSE OF

WESTERN UNITED STATES

BY H. Y'^ABE

COMPARISON OF THE CRETACEOUS FLORAS OF CALIFORNIA WITH THOSE OF

OTHER CRETACEOUS AREAS

BY V. H. KNOWLTON

Read by John C. Merriam.

Discussion of the preceding five Papers

lu reply to Trofessor Schucliert's query as to the cause of the discordance
between the floras and the faunas of the Knoxville when used as indicators of
age of this formation, Doctor Stanton stated that the faunal evidence was
not strong.

I'rofessor Smith noted that the Knoxville and Mariposa are never found in
contact. The persistence of striated Aucella> later than the Mariposa is not
especially significant. It indicates that the time interval was not great.

Doctor Stanton remarked that paleohotanists make no distinctions between
the Upper Knoxville and Horsetown floras, while there is a distinct difference
in the faunas.

Professor Schuchert stated that if there was a great movement at the end
of the Jurassic there must be a marked unconformity- and the disturbance
must be reflected in the faunas.

Doctor Ulrich stated that there was undoubtedly considerable land during
the Jurassic-Cretaceous interval. Since the age is determined by the marine
faunas, and since the last of the Jurassic flora would leave its impression on
the Cretaceous flora, there seems to be no agreement between the evidence de-
rived from these sources. It was suggested that the standards may not agree;

ABSTRACTS AND DISCUSSIONS OF PAPERS 415

that possibly an older portion of the Cretaceous is represented here with no
equivalent in the European standard.

Professor Schuchert stated that there is no marked change in the flora of
the Jurassic, and that the change occurs in the Lower Cretaceous. On the
other hand, the marine faunas change rapidly and at the end of the periods.

Professor Merriam said that the Cretaceous offers one of the best examples
in the use of the migration of strand-lines for correlation purposes. Before
an adequate time classification can be established it is necessary to know more
of the causes of life change and of diastrophic change. More is known of life
changes than of diastrophic movements.

Professor Osborn remarked that the lines drawn by Cuvier and a number
of other early workers were based on paleontologic evidence. The chief objec-
tion to the use of diastrophism for correlation purposes is that its effects have
not been world-wide. The continent of Africa has remained approximately
the same for a considerable length of time.

Doctor Ulrich stated that the systems were originally l)ased on lithology,
and it was afterward recognized that they could be determined by their faunal
content. He cited the Silurian and Devonian as examples. The idea of world-
wide diastrophism depends on the meaning of the term. It refers to any move-
ment which will affect the strand-line.

Professor Schuchert emphasized the world-wide influence of diastrophic
movement, and referred to it as due to periodic shrinking of the earth's crust.
The influence of diastrophism is exerted over I)oth marine and continental
deposits.

Doctor Matthew stated that he believed theoretically in diastrophism as an
aid in correlation, but doubted its value in practical application. He recog-
nized the obvious evidences of world-wide diastrophism, as in the Cretaceous.

The meeting theu adjourned.

Session of Friday, August 6

The mooting was oallod to order by Truf. JFenry F. Oshorn at 10
oV'loc'k, in Bacon ITall, room 2(m;, ITniversity of California. Tlio sym-
posium, "Correlation between tlie Mioceiu> of the Paoifio region and that
of otber areas of the woi-bl," was tbo topic of tbis session, and the morn-
ing was devoted to tbo reading of Ibo fullowing pajxTs:

INTRODUCTORY /?/;iM /.'AN OY COnUET.ATJOX OF MWCKyE

liY llKNin lAIKI' IKI.l) OSMORN

COllRELATIOX OF TlIF LOW El! MIOCENE OF CALIFORNIA
MY UAI.ril AUXOI.l)

416 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

REVIEW OF THE MIOCENE AND OLIGOCENE FAUNAS OF CALIFORNIA

BY B. L. CLARK

MIOCENE OF THE WASHINGTON-OREGON PROVINCE AND ITS RELATION TO
THAT OF CALIFORNIA AND OTHER MIOCENE AREAS

BY CHARLES E. WEA^^R

VERTEBRATE FAUNAS OF THE PACIFIC COAST REGION
BY JOHN C. MERRIAM

The meeting was then adjourned until the afternoon.

The meeting was again called to order hy Professor Osborn at 2 o'clock.
The s}Tiiposium on the "Correlation of the Miocene" was continued and
the following papers were read :

CORRELATION BETWEEN THE MIDDLE AND LATE TERTIARY OF THE SOUTH
ATLANTIC COAST OF THE UNITED STATES WITH THAT OF THE PACIFIC
COAST

BY E. H. SELLARDS

RELATION OF THE MIOCENE MAM]\IALIAN FAUNAS OF WESTERN UNITED
STATES TO THOSE OF EUROPE AND ASIA

BY WILLIAM D. MATTHEW

CORRELATION OF THE MIOCENE FLORAS OF WESTERN UNITED STATES WITH

THOSE OF OTHER MIOCENE AREAS

BY F. H. KNOWLTON

Read by John C. Merriam.

FLORA OF FLORISSANT
BY T. D. A. COCKERELL

Discussion of the papers dealing with tlie correlation of the Miocene
was deferred. Prof. J. C. Merriam was called to the chair. The re-
mainder of the afternoon was devoted to the reading of the following
papers of general interest :

FAUNAE GEOGRAPHY OF THE EOCENE OF CALIFORNIA
BY R. E. DICKERSON

RECENT WORK ON THE DINOSAURS OF THE CRETACEOUS
BY HENRY FAIRFIELD OSBORN

ABSTRACTS AND DISCUSSIONS OK PAPERS 417

HISTORY OF THE APLODONTIA GROUP
RY W. P. TAYLOR

SOME PROBLEMS EyCOUNTERED IN THE STUDY OF FOSSIL BIRDS OF THE

WEST COAST

BY L. H. MILLER

A number of important papers were not reached in tlie program, as
the Societ}' adjourned to take part in the excursions on tlie following day.

Eesolution of Thanks

Prof. Henrv F. Osl)orn offered a resolution instructing the Secretary
to tender to the officers of the American Association for the Advance-
ment of Science, to the President of the University of California, and to
the President of Stanford T^ni versify the thanks of the members of the
Paleontological Society and an appreciation of the courtesies extended to
the Society at this meeting.

The meeting then adjourned.

Excursions

Following the meeting a numl)er of the members of the Society par-
ticipated in excursions to some of the principal localities of paleontologic
interest in California.

On Saturday, August 7, under the direction of Prof. John C. Merriam,
the San Pablo Bay syncline was visited. A section, including faunas
from the Chico-Cretaceous to the Eodeo-Pleistocene, was examined In' the
party.

Under the leadershi)) of Prof. A. C. Lawson and Dr. T>. L. Clark, the
section near Walnut Creek was examined on IVfonday, August 9, and on
the following day IMonnt Diablo was visited. The members of the partv
were al)le to examine a section ranging from the Franciscan-Jurassic to
the Pleistocene and ollVr'ing much of structural and paleontologic interest.

The Eicardo Pliocene beds exposed on the Mohave Desert were visited
by several members of tlie Society on Thursday, August 12, with Dr.
J. P. Buwalda as leader.

Following the excursion to Ificaido the famous Pleistocene asphalt
deposits of Ifancho L;i r.i-cii wei'c \isiteil. under the leadership of ^Ir.
Frank S. I )aggett and Professor Meii'iam. on I''ri(hiy, August 13. On
the same day the ));irty visited the .Museum of History, Science, and Art,
in Los Angeles.

418 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

Under the leadership of Dr. Ralph Arnold, the splendid marine Pleis-
tocene sections exposed at San Pedro and Loner Beach, near Los Angeles,
were examined on Saturday, Auniist 14. On the excursions in and around
Los Angeles the visiting members were most hospitably entertained,
through the courtesy of the Museum of History, Science, and Art and
the Chamber of Commerce of Los Angeles.

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Vol. 26, pp. 419-446 November 24, i9i5

PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY

I. ON THE RELATIONSHIP OF THE EOCENE LEMUR

NOTHARCTUS TO THE ADAPID^ AND TO

OTHER PRIMATES 1

11. ON THE CLASSIFICATION AND PPIYLOGENY OF THE

LEMUROIDEA

BY WILLIAM K. GREGORY

{Presented before tlie Faleontological Society December 31, WIJ/., and,

in abstract, August Jf, 1915)

CONTENTS

Page
I. On the relation.'^liii) of the Koceiie lemur Xothantu-s to the Atiapiilie

and to other I'rimate.s 419

Results obtained by other investigators 419

Observations of tlie writer 421

Conclusions 425

II. On the classification and pliyloseny of the Lemuroidea 426

On the basicranial region of the Lemuroidea 426

A classification of the Lemuroidea 432

Phylogenetic summai'y 4.39

Bibliography 443

I. 0\ TIIK l(i:i,.\TI()XSIlIl' OK TIIK EoCENE LeMUR Notharcfus TO THE
AdAI'ID.K AM) TO OTHER PrIMATKS "

RE8VLr,S OBTAINED liV OTHER INVEffTIGATORS

'V\w gcinis Xollnirchis was rouiidiMl by Leidy in ISlO upon a small
fossil jaw which liad hccn foiiiid in the Eocene fni-niation near Fort
Bi'id,<rcr. Wyotiiiiiii-. Leidy was iiol ahlc to refer the animal to any
e.vistiiiii- (ii'dci' of inaiimials. II( ii(itc(l iis resemblances to carnivorous
niainnials on the diic hand and lo ccitain supposed Eocene pachyderms

III) the dthcl".

> Manuscript received l).v tlie Secretary of tlie (ieoloRicai Society August 10. 101.").
'-'I'lils pai)cr and llio following one contain an oiillim" of oliservations and conclusions
whlcli will bp fully presented in a Memoir of the American Museum of Natural Ilistor.v.

(419)

420 \V. K. GREGORY NOTHARCTUS AND LEMUROIDEA

Marsh, who described a similar jaw fragment the next year, 1871,
also noted its resemblances to the supposed suilline pachyderm Hyopsodus.
In October, 1872, however, Marsh described some better specimens, which
included parts of the limb bones. He remarked that the principal parts
of the skeleton of these animals were formed much as in some of the
Lemurs, especially the limb bones, and he referred the animals to the
order Quadrumana. He also gave the correct dental formula. The
subsequent systematic history of the group was developed by Cope, Marsh,
Osborn, AVortman, and ^Matthew in a long series of papers, extending
from 1871 to the present time. Through tlu'ir hibors three valid genera —
Pelycod'us, Notharctus, and Telnialt'stes — inchidiug perhaps a dozen or
more nominal and valid species, have been recognized, constituting the
family Limnotherida? of Marsh, or JSTotharctidie of Osborn.

The prohknu of the relationship of this family to other Eocene fam-
ilies, namely, to the Hyopsodontidae, to the Adapidaj of Europe, and to
the modern Lemurs, has had a confusing history. Marsh, as it now
seems, correctly placed the group as Ijeing moi'e or less related to the
modern Lemurs. Cope was long deceived by a false association of
Creodont claws with teeth belonging to Pelycodus, and on this miscon-
ception ho based his suborder Mesodonta (1876). This error was cor-
rected both by Schlosser (1887, page 22) and by Matthew. Cope also
held that the genus Notharctus and its allies were related to the European
Eocene genus Adapis, and he referred them all to the family Adapidte
(1885).

Osborn, in 1902, revised the genera and species of American Eocene
Primates, defined the family Xotharctidip, and traced the history of the
family from the Lower Eocene species of Pelycodus to the Upper Middle.
Eocene species of Telmalestes. Up to this time these animals were
known chiefly from the dentition, and as Professor Osborn did not regard
such material as adequate, he left unsettled the general problem of the
relationships of this family, provisionally retaining them in Cope's group
Mesodonta.

Wortman, in 1904, endeavored to show that the Hj^opsodontidge, which
had been supposed to be related to the N'otharctidae, were not Primates
at all, but Lisectivores. He regarded Cope's Mesodonta as an unnatural
assemblage. He placed Notharctus with the European genus Adapis in
the Adapidae, but he regarded this group as not at all nearly related to
the modern Lemurs ; he thought rather that the Adapidse stood near to
the beginnings of the higher Primates, especially the New World
monkeys. Accordingly he placed Notharctus, along with Adapis, in the
same division with the monkeys both of the New and the Old World,

RESULTS OBTAINED BY OTHERS 421

the great apes and man, and to this assemblage he gave the name
Neopithecini, or modernized Primates. This opinion, therefore, would
be highly important if true, for, if confirmed, it would mean that the
Adapidse represent an early evolution stage of the group that includes
man and the higher apes.

Stehlin, in 1908, in his monographic revision of the European genus
Adapts, which ranges from the Lower to the Upper Eocene of France,
concluded from a comparison of the dentitions that the American Nofh-
ardus and its allies were not nearly related to Adapis, but that the two
formed divergent contemporary families in Europe and America, which
Avere not more nearly related to each other than to other families of
Primates. Stehlin showed that the x\dapidae in the fundamental archi-
tecture of the skull were related to the modern Lemuridw.

Schlosser, in Zittel's Grundziige der Palaontologie (1911), referred
Notharctus and its allies to the Adapidre and suggested that the European
genera might l^e derived from the more primitive ISTotharctid genus
P el y cod us.

As long as N othardus and its allies were known chiefly from the denti-
tion and scattered limb bones, and as long as the architectural plan of
the skull was but i)oorly known, there was room for these wide differences
of opinion regarding the relationships of the N'otharctidse and the
Adapidae with each other and with the higher Primates.

OBSERVATIONS OF THE WRITER

In 190,'^ and subsequent years, however, American IMuseum expeditions
under ]Mr. Walter Granger, working in the Middle Eocene formations of
Wyoming, discovered a series of specimens which has afforded an ade-
quate knowledge of the skull, vertebrge, and limbs of Nothardns. This
material was generously placed in my hands by Doctor Matthew, with
the consent of Professor Osborn, and it has afforded much new evidence
regarding the relationship of the Notharctidje with the Adapida^, with
the Lemurs, and w ith other groups.

I purpose, tlu'i-d'oi'i.', to present very briefly some of the evidence wliich
has led me first to adopt the view of Schlosser, tliat the Notharctidge
and Adai)i(Ia' aie closely related to each other and to the Lemurs, and,
secondly, to inodiry largely the view of Wortniau regarding their several
relationships with the Lemurs and willi the highci- Pi-imates.

'I'he American genera Nothardus and Tclmalesles agree with the

lMiidj)ean genera Addpis and Lrpfadn/iis. not only in the general form

of the skull as a whole, but also in the form of the orbit, malar, sagittal

and lambdoidal crests, lower jaw, and dental formula. Veiy important

XXXIII — Bull. Geol. Soc. A.m., Vol. 26. 1914

422 W. K. GREGORY NOTHARCTUS AND LEMUROIDEA

is the close agreement between Adopis and Notharctus in the form and
relations of the I'acrymal. In both genera the lacrymal was largely
within tlio orbit, instead of being widely extended on the face, as it is in
Lemurs, and the lacrymal foramen was marginal, instead of preorbital;
and this condition is, I believe, the primitive one for Primates in general,
the existing Lemurs having lost this and other primitive lemuroid char-
acters. The generic difEerences are obvious and may be passed over.

In the architecture of the skull Adapis and Notharctus reveal differ-
ences which are chiefly quantitative, or allometric. In a skull of Noth-
arctus in the American Museum (number 11477), the basicranial region
has been skilfully freed from the matrix by Mr. Anderson. It exhibits
the following important characters: (1) the pterygoid plate of the
alisphenoid is continued down outside the bulla; (2) the bulla represents
an expansion of the periotic; (3) the auditory prominence or cochlea
bears on its outer surface a bony canal for the internal carotid artery ;
(4) this canal runs forward to the anterior end of the bulla, and there
it enters the posterior part of the basisphenoid ; (5) the entrance to the
carotid canal, or posterior carotid foramen, is at the postero-external
corner of the bulla; (6) immediately external to the posterior carotid
foramen is the stylomastoid foramen, for the seventh nerve.

In Adapis. as figured by Stehlin (1912), the basicranial region is
fundamentally similar to that of Notharctus. Here the pterygoid plate
of the alisphenoid likevnse extends outside the bulla, which is again only
an expanded portion of the periotic; the cochlea has the same carotid
canal, which also runs forward to the anterior end of the tympanic
chamber; the stylomastoid foramen is in the same position. Stehlin
found preserved in some specimens the delicate tympanic annulus which,
as in Notharctus and all other true lemuriform lemuroids, was inside the
expanded bulla.

The dentition, however, offers divergent characters. The upper in-
cisors of Adapis are more chisel-like than those of Notharctus, the pre-
molars are more compressed, the molars are tritubercular, the postero-
internal cusps of the molars are formed by the upgrowth of the basal
cingulum, and there is no median external cusp, or mesostvle.

In Notharctus, on the other hand, tlie jjosterior premolars are wider
transversely, the posterointernal cusp of the molars is formed by a
splitting or division of the protocone, and there is a. progressively de-
veloped mesostyle.

The different modes of forming the posterointernal cusp of the upper
molars are correlated with equal differences in the entoconid in the lower
molars. By fitting the upper and lower teeth together I find that in the

OBSERVATIONS OF THE AUTHOR 428

case of Notharctus the constriction between the two inner cusps marks
the spot where the entoconid of tlie lower molar sweeps across the in-
ternal ridge of the upper molar. In Notharctus, as in man}^ Perisso-
dactvls, the progressive development of the tetartocone, or posterointernal
division of the ])rotocone, is correlated with the progressive developjnent
of the entoconid of the lower molars. The progressive development of
the mesostyle is also correlated with a partly transverse excursion of the
mandible and with the Y-like modification of the para- and metacones.

In the Adapida^, on the other hand, the entoconids, for some reason,
remained small ; there was consequently no correlated development of
the tetartocone, and the posterior cingulum was thus free to grow \^v in
a normal manner into a true hypocone, which fits into the valley of ihe
trigonid. Also, there being less transverse movement of the mandilde,
the para- and metacones did not become V-shaped and the mesostyle
failed to dcveloji. But, although these differences in the dentition are
very marked in the later members of the Adapinse and Notharctina\
tliey ai'e less pronounced if we compare Stehlin's Protoadapis with our
American Pelycodus. The oldest forms of Pelycodus, which have recently
been described ])y Doctor Matthew,^ have extremely primitive trituber-
cular u])]ier molars, without any posterointernal cusp, and they have a
pattern which, according to accepted principles of dental evolution, is
structurally ancestral to the two divergent lines seen in the Notharctinae
and Adapina.

Stehlin (1912), noting the marked differences in the dentition between
Adapis and Notli(ii'< hr;, l)ut without investigating the functional signifi-
cance of these differences, concluded that the Adapida? and the Xoth-
arctidse were rather \\i(h'ly separated families, not more nearly related
to each other than to oflicr groups of lemuroids ; but if Doctor Stehlin
had realized that these observed differences were all correlated with a
divergent habit of swinging the mandible, and that the more primitive
Notharctids of the Inwer Eocene appear to be structurally ancestral, both
to the Adaiuda' and Xothai('tida\ and ('S]iocially if he had had a well-
preserved skull of Xo/liarcl lis, and could ]ia\c seen the fundamental simi-
larity tlirouglioui. I think it probable that be would have been led to the
conclusion that the two gi'on|)> are lather nearly related.

In Aihijris we see the same dental rorninhi as in the N'otharctintX!, but
the i-amus is nnw stout and the region of the angle is nnieh expanded,
paralleling in this respect such advanced lemuroids as the Indrisinje. In
fact, the dill'eiences in the lowci- jaw l)etween Notharctus and Adapis are
not as great as those ht.'lween Lcpilriinir of the Domurina^ and Indris of

"Bull. Amer. Mus. Nat. Hist., vol. xxxlv, 1!)15, pp. 429-483.

424 W. K. GREGORY— XOTHARCTUS AND LEMUROIDEA

the Tndrisinas. With the expansion of the angle, the areas of insertion
of the pterygoid muscles and of the masseter and temporalis are greatly
expanded. AVe accordingly find that Adapis also has the malar and the
sagittal and lambdoidal crests highly developed, and that in the dentition
this superior cnishing power is shown in the expanded talonids of the
lower molars and in the expanded protocones of the upper molars. In
short, the skulls and dentitions of Adapis and NotJiarctus are funda-
mentally similai- in architectural plan, but differ in adaptive details.

The limbs of Adapis are also fundamentally similar to those of Noth-
arctus, Adapis being more robust. It is noteworthy that the astragalus
of Adapis agrees with that of Notlmrdus in having a narrow vertically
extended trochlea, whereas in all the Anthropoidea the trochlea is wide
and has more distinct keels.

I would therefore define the family Adapida^. and the included sub-
families Xotharctinag and Adapinoe as on page 433, below.

Coming now to the structural relationships of the N"otharctida:> to
modern Primates, I can only emphasize what I liave previously stated
(1913), that in my judgment there is no justification for associating the
Notharctinffi with the South American monkeys, as AYortman (1904) has
done in placing both Adapis and Notliarctus, along with Tarsius, in his
major group Xeopithecini. The Notharctinje are certainly in a lemuroid
rather than a simian stage of evolution, and they differ from modern
Lemurs chiefiy in being more primitive and in having avoided both the
peculiar lemurid specialization of the lower incisors and canines and the
secondary elongation of the lacrymal on the face.

The skull of NotJiarctus is lemur-like in general form. I'he face is
long; the postorbital bar reaches the malar; the malar is essentially
similar to that of Lemurs; the orbit is not shut oft' from the temporal
fossa by a transverse partition. But in many ways tlie skull of NotJi-
arctus is far more primitive than that of existing Lemurs and approaches
the skull of other primitive Eocene mammals; thus the brain-case is
relatively small and is surmounted by well-developed sagittal and lamb-
doidal crests; the jaw is stout: the dental formula is I-' C— ' Pj' M'-'

which differs from the primitive Placental formula of — ' — —' ;r only

^ 3. ]. 4. 3. "^

in the loss of one upper and one lower incisor. The base of the cranium
is fundamentally similar to that of the Lemuridos.

The existing genus Lepilemur, which in many characters is perhaps
the most primitive of the Lemuridas, is far more advanced than NotJi-
arctus in the expansion of its brain-case, in the loss of the sagittal crest.

OBSERVATIONS OF THE AUTHOR 425

in the weakening of the lower jaw, and especially in the characteristic
lemurid specialization of the incisors, canines, and anterior premolars —
a specialization which Notharctus had not assumed.

The lower jaw of the earlier species of Notharctus has two important
primitive characters in common with that of modern Lemurs : First, the
two halves are suturally separate at the symphysis, whereas in the Anthro-
poidea, including the Xew World monkeys, or Platyrrhinse, and the Old
World monkeys, apes and man, or Catarrhinse, the opposite halves are
fused at an early stage of development ; secondly, the angle forms a long
backwardly projecting process for the insertion of the internal pterygoid
muscle, whereas in the Anthropoidea the angle is much expanded. The
lower jaw of Notharctus is also iiiore primitive than that of the existing
Lemurs in retaining erect canines and incisors.

The upper incisors are of a very primitive compressed type, which
could give rise, witli slight modifications, to the upper incisors of the
existing Microcehus of the Jjemuridie, and in another way they resemble
the incisors of Adapis.

The vertebral column is, on the whole, rather close to that of existing
Lemurs, considerably different from that of existing ISTew World Pri-
mates and widely different from that of Old World Primates.

For example, the lumbar centra are elongate, with depressed ends, as
in Lemurs, while in the Anthropoidea the centra are short and wide and
the ends are vertically thicker. Again, the wide parapophyses of the
lunibars are similar to those of Lemurs.

Tlie pelvis is decidedly Lemur-like in the lyrate form of the ilia, in
the prominence of tlie ])rocess for the rectus femoris muscle, and in the
non-expansion of the ischia. The remaining limb bones and the hands
and feet are strikingly like those of Lemur, the chief differences being
that the metapodials and the humerus are decidedly short — a primitive
character.

CONCLUSIONS

Tn conclusion, the type of skeleton which is represented in Notharctus
appears to l)e considerably nion' [)rimitive than that seen in any later
Primate ; it has been transmitted, with minor changes, chiefly of propor-
tions, to modern Lemurs, while very distinct traces of this skeletal pat-
tern are retained in varying degrees by the Hapalidai and Cebidae. From
the skeletal pattern of the Old Woild Primates, however, it is separated
by a wide structural hiatus.

426 AV. K. GREGORY NOTHARCTUS AND LEMUROIDEA

II. On the Classification and Phylogeny of the Lemuroidea

ON THE BASICRANIAL REGION OF THE LEMUROIDEA

As the characters of the base of the cranium are of great systematic
and phylogenetic importance in the Primates, as well as in all other
mammals, I may begin by describing in a general way the principal
types of auditory bull^ in the Lemuroidea and the principal relations
of the internal carotid artery and its branches to the osseous parts of the
cranium in that group.

The structure of the auditory bullae and surrounding parts has been
very carefully studied in the recent Primates by Winge, Leche, Forsytb
Major, Van Kampen, and others, whose researches afford adequate data
for the interpretation of this region in such extinct Primates as Noth-
arctus, N ecrolemur . and Anaptomorphus. In the more primitive form
of the auditory region the tympanic membrane is stretched on a ringlike
tympanic bone or ectotympanic, and this lies well within the bulla, or
tympanic chamber, so as to be completely concealed by the ventral wall
of the bulla, as seen from below ; the bulla itself in all Primates appears
to be formed as an expanded shell of the periotic. The mastoid region
is sometimes inflated. AVith minor variations, this relation of the ring-
like tympanic to the inclosing bulla is found in all known members of
the Lemurina?, Megaladapinge, Chirogaleinaj, Indrisin^, Archaeolemurinse,
and Chiromyidffi, all of which are found in Madagascar. This series of
lemuroid families and subfamilies will be referred to below as the
Lemuriformes. The material of Adapis, figured by Stehlin (1912), and
the American ]\Iuseum material of Notharctus afford proof that in these
genera the structure and relations of the auditory bulla and of the ecto--
tympanic conformed to the plan seen in Lemur and Propifhecus, and
this fact, in conjunction with other evidence, shows that the Notharctinse
and the Adapin», together constituting the family AdapidfE, should be
referred to the series Lemurifonnes.

In the more specialized form of auditory region the ectotympanic bone
is not hidden l:)eneath the bulla, but forms its external portion and projects
externally in a tubular osseous auricular meatus. The bullae in these
forms are much inflated and extended anterointernally toward the mid-
line. This series includes, first, the Oriental Tarsius and its extinct
Lower Eocene American relatives, Anaptomorphus, Hemiacodon, and
their allies, all referred here to the Tarsiidae; and, secondly, the Upper
European Eocene genera Necrolemur and Microclicerus, forming the
family Microchcerids. This series will be referred to below as the
Tarsiiformes.

BASICRANIAL REGION OF THE LEMUROIDEA 427

In the members of the family Lorisidie, which includes all the existing
non-Malagasy lemnroids except Tarsius, namely, the Galagos and Pottos
of Africa and the Lorises of the Far East, the auditory region agrees
with that of the Tarsiiformes in that the ectotympanic lies outside the
bulla, of which it fornas the outer margin. In the Lorisid^, however,
the ectotympanic does not form a protruding tubular auditory meatus,
but merely a circular opening into the bulla; in these forms the mastoid
is much inflated and its sinus extends widely into the inflated medial
wall of the bulla, a character foreshadowed in Necrolemur of the Tarsii-
formes. The Lorisidge in many respects mingle the characters of the
true Lemuriformes with those of the Tarsiifonnes and are here referred
to an intermediate series which may be named Lorisiformes.

The complex relations of the branches of the internal and external
carotid arteries to the auditory region and to other parts of the cranium
have been explored in the Primates, especially by Tandler (1899), Winge
(1895), and Leche (1896), the work of Tandler being the most compre-
hensive. Van Kampen (1905) has partly applied their results in his
work on the tympanic region of mammals. Wortman (1903) attempted
to apply this line of investigation to the study of fossil Primates, but as
he was equipped with the imperfect data furnished by Huxley and
Mivart, rather than with the fuller and more correct results of Tandler,
Zuckerkandl, and others, his interpretation of the conditions in recent
and fossil Primates is partly erroneous. Stehlin (1912) lias made a
thorough study of the basicranial region of Lemur and Adapis with
special reference to the course of the internal carotid.

Tandler's researches are especially important as furnishing a rational
explanation of the complex and varied arrangements of the carotid
arteries and their brandies throughout the mammalia. The internal and
external carotid arteries are regarded by embryologists as having been
derived phylogeiietically from the afferent vessels of the branchial arches
of lower vertebrates. In mammals some of the minor branches belonging
to adjacent arclies tend to anastomose with each other, and when this
happens, at-cording to Tandler's theory, the terminal branches of the
more anterior arches are captured, as it were, by the main trunks of the
more posterior arches. In this way some of the minor camtid branches
in the orbit, which appear to liave been supplied originally hy tlie hist
visceral arch, are found in certain mlult mammals to be supplied by the
main vessel of the second viscci'al ai-cli. which is the stapedial artery.
Again, the minor branches of the stapcilial artery arc oficn captured by
the main li'unk of tlic ihii-d viscci'al arch, which is the external carotid
artcr}', aiiil as a I'csnlt of this captiii-c the stapedial arteiT \{<c]\' is often

428 AV. K. GREGORY- — NOTHARCTUS AND LEMUROIDEA

al)seiit in the adult, although present in the embryo (as in man). Ac-
cording to this theory, the recent Insectivores retain an arrangement of
the carotid branches which is more primitive than that which is char-
acteristic of the Lemuriformes, as described below, while these in tarn
are more primitive than the Tarsiiformes and the higher Primates.

In Erinaceus, according to the researches of Hyrtl, Tandler, and
others, the internal carotid enters the bulla from the rear, through a
foramen that is incompletely separated from the stylomastoid foramen.
Inside the bulla the arter}^ divides into two main branches, named the
arteria pi'omentorii and the art. stapedia. The art. promentorii, which
is homologous with the internal carotid of man, bends around over the
cochlea, or auditory prominence, and, passing forward and inward, pierces
the side of the basisphenoid, as in Marsupials, Centetes and Lemur;
entering the cerebral chamber lateral to the sella turcica, it joins the
main cerebral artery. The stapedial branch is of large size, and after
piercing the stapes runs forward in a groove in the roof of the t3Tnpanic
cavity, issuing into the temporal fossa through a notch, or foramen, in
the tympanic process of the alisphenoid, posteroexternal to the foramen
ovale ; the carotid notch or foramen transmits an important branch named
the "ramus inferior," which runs forward to the orbit and gives rise to
several minor l^ranches. The other branch of the stapedial artery
("ramus superioi^') comes off from the ramus inferior in the anterior
part of the tympanic fossa ; it passes backward and upward through the
petrosal. In Tupaia, representing the suborder Menotyphla of the order
Insectivora, Hyrtl's figures show that the internal carotid likewise divides
into two main branches — the art. promentorii and art. stapedia — which
run in bony canals in the tympanic cavity; the ramus inferior is large
and issues from the tympanic cavity anteriorly, as in Erinaceus.

In all the recent Lemuriformes the internal carotid differs from that
of the insectivores chiefly in that the ramus inferior of the stapedial
artery is always wanting, and consequently there is no carotid foramen
in the tympanic region of the alisphenoid — apparently, according to
'J'andler's view, because its terminal branches have been captured bv the
external carotid.

The internal carotid in typical lemurs enters the bulla on its postero-
external border medial to and below the stylomastoid foramen.* This
posterior carotid foramen leads into a short carotid canal, which runs

* Doctor Wortman (1903, page 167) errs in locating the carotid foramen of Lemur on
tlie posterointernal border of the bulla. The foramen at that point (marked cc in his
figure 101, page 166), according to Van Kampen (1905, page 658) and other authorities,
is a part of the foramen laoerum posterius ; it leads directly into the cranial chamber
and plainly gives exit to a cranial nerve, probably the eleventh.

BASICRANIAL REGION OF THE LEMUROIDEA 429

over the auditory prominence, or cochlea; the canal divides into two
branches for the arteria promentorii and the art. stapedia respectively.
The arteria stapedia traverses tlie stapes and then runs upward through
the periotic, this branch being homologous with the ramus superior of
Insectivores. The arteria promentorii runs forward in the outer wall
of the anterointernal extension of the bulla, pierces the basisphenoid,
and emerges into the cerebral chamber lateral to the sella turcica, as in
Insectivores.

In Notharctus, as shown in an American Museum specimen, and in
Aclapis, as shown in Stehlin's material, the foramina and canals for the
arteria promentorii and the art. stapedia were identical in position with
those in Lemur and Propiikecus and quite different from those of the
Tarsiiformes. In modern Lemuriformes, and very likely in Notharctus
and Adapis, the arteria promentorii was small and the major part of the
blood supply of the cerebral arteries was furnished by the vertebral
arteries through the ramus communicans posterior. In the Tarsii-
formes, on the other hand, as well as in the whole suborder Anthropoidea,
the vessel which is supposed to be homologous with the arteria pro-
mentorii is enlarged, forming the typical "internal carotid" and furnish-
ing a large part of the l:)lood supply of the cerebral arteries. Tandler's
observations and conclusions suggest that the latter condition has been
derived from the former.

Another distinction between the Lemuriformes and the Tarsiiformes
is that in the former the stapedial artery and its ramus superior are
always well developed, while in the latter they are typically reduced or
wanting.

These facts and considerations afford further evidence for referrincr
Notharctus and Adapis to the Lemuriformes rather than to the "ISTeo-
pithecini" of Wortman (1903, pages 172-174), which is an unnatural
assemblage composed of the Adapida3 and all the families of the Antliro-
poidea.

While the typical Lemuriformes (including the Lemurina', the In-
drisidse, and the Chiromyidffi) have the main branch of the internal
caiotid passing over tlie cochlea and through the tympanic cavity, a
puzzling exception to this rule is furnished by the mouse lemurs and
other dwarf lemurs of the subfamily Chirogaleinae. In these genera the
observations of Mivart. ^^■illg('. 'l^mdler, and \i\n Kampen have estab-
lisbed tlio fact that the main l)ranch of the internal carotid does not
l)ass through ihc tympanic cnvitv at ;ill. l)ut enters tlie skull through a
pair of large foramina laccra media"' iiii mediately antornintoninl to tlie

"Foramen lacenim anterius of Ocimau aulliois.

430 W. K. GREGORY NOTHARCTUS AND LEMUROIDEA

bullge. A'^an Kampen (1905, page 661), from the observations of Zucker-
kandl and Wincza, suggested that this condition is secondary, and my
observations on the skull of the Chirogaleinaf also lead me to suspect
that this subfamily has been derived from more normal lemurs.

The Lorisidffi (a family which has been referred to above as the
Lorisiformes) resemble the Chirogaleinag in the fact that the main branch
of the internal carotid passes through tlie widely open foramen lacerum
medium, l)ut there is also a very small branch that enters the tympanic
cavit}' from the inner side. The observations of Tandler and Winge
leave it doubtful whether this small branch represents both the arteria
promentorii and the arteria stapedia or only the latter (Van Kampen,
1905, pages 671, 672).

Passing to the Tarsiiformes, the foramina in the basicranial region
of Necrolemur are shown in three good skulls, belonging respectively to
the British Museum, the Princeton University j\ruseum, and the Museum
of Comparative Zoology of Harv^ard Universit}^ which I have studied
with great care. There is a foramen on the inner face of the bulla that
appears to be the main posterior carotid foramen. There are no visible
foramina in the position of the foramina lacera media of the Nycticebidse,
and if these were present they must have been covered over by the
greatly expanded bullae, this indicating that the carotid pierced the bulla
and traversed the tympanic cavity. In front of the greatly inflated bulla
and on the outer anterior face of the enwrapped pterygoid wing of the
alisphenoid are two foramina which, by comparison with Tarsius, appear
to be the for. ovale and for. rotundum (respectivelv for the ramus
mandibularis and ramus maxillaris trigeraini). Internal to the ala tem-
poralis is the foramen (ostium) tubae Eustachii. A postglenoid foramen
is present. On the whole, in the position of the foramina, especially that
for the carotid, Necrolemur is nearer to Tarsius than to any of the
Nycticebidffi.

The famous skull described by Cope as "Anaptomorphus" Jiomunculus^
has recently been further developed from the matrix by Mr. A. E. Ander-
son, under my direction, and thus the interior of the bulla has been
revealed. The basicranial region, as a wliole, is remarkably similar to
that of Tarsius, save that the trochlea, or auditory prominence, is much
smaller. The bulla was greatly inflated, as in Tarsius and Necrolemur,
and its anterointernal extension likewise completely covered over the
region where the foramen lacerum medium is located in tlie N'ycticebidffi.
The internal carotid must surely have traversed the tympanic chamber,
but its exact course is doul)tful. Tii Tarsliif; it pierces the middle of the

" Tetonius Matthew.

BASICRANIAL REGION OF THE LEMUROIDEA 431

bulla on the lower surface, then passes directly upward (craniad) through
the margin of the septum of the cavum bullae, passing into the cranial
cavity at the apex of the enlarged cochlea (Van Kampen, 1905, page
67G). In the only known skull of " Anaptomorplius" homunculus the
whole lower wall of the l)u]la is broken away, so the place of entry of the
carotid into the cavum bulliE is not indicated. To the small cochlea is
attached a remnant of a long septum, which may have carried the carotid
canal.

The chief conclusions which may provisionally be drawn regarding the
course of the main branch of the internal carotid in the Lemuroidea are
as follows :

(1) That most of the Lemurifonnes retain a primitive lemuroid con-
dition, in that the arteria promentorii, or main branch of the internal
carotid, in passing through the bulla, runs forward in a bony tube along
the outer side of the cochlea, or auditory prominence, and pierces the
basisphenoid. These forms have no ''foramen lacerum medium," in the
ordinary sense of the term, since the point where the carotid pierces the
basisphenoid is concealed from below by the bulla. This condition is
characteristic of the Kotharctinge, Adapins, Lemurina?, Indrisinse,
Archasolemurinse, and Chiromys.

(2) In the Chirogaleina? the main branch of the internal carotid does
not pass through the bulla at all, but enters the brain-case in front of
the bulla through the large foramen lacerum medium. This condition
appears to be a later specialization.

(3) Of the Tarsiiformes, the Upper Eocene Necrolemur had no
foramen lacerum medium, and the main l^ranch of the internal carotid
apparently entered the \>u\\a tiirough a carotid foramen on the inner or
medial surface of the bulla. Whether the arteria promentorii ran through
a tube over the auditoiw prominence is not known. In Tarsiiis the
carotid foramen is enlarged and shifted to the ventral surface of the
bulla, and the carotid canal, or tube, only touches the cochlea at its apex.
In "Anaptomorplius" the carotid probably pierced the bulla either as in
Necrolemur or as in Tarsius, but its course inside the bulla is doubtful.

(4) In the Lorisifonnes (Ix)risidfe) the main branch of the internal
carotid did not pierce tlie bulla at all. hut entered the brain-case through
the widely open foramen lacerum uicdiuiu, a condition which is probably
secondary, as in Chirogaleina^.

Thus the true Lemuriformes, with the exception of ihc riiirogaleinae,
are distinguinbcd by retaining an apparently primitive arrangement of
the carotid foraniiiui and canals; XrcrolniiNr and the Tarsiida, including
"Anaptomurpkas' Iioiiiuik iilus. arc cbaractcrizt-d by a more advanced

432 W. K. GREGORY NOTHARCTUS AND LEMUROIDEA

arrangement leading to that of the higher Primates, while the Chiro-
galeinse of the Lemuriformes and the Lorisidse of the Lorisiformes have
independently acquired an aberrant arrangement by which the main
branch of the internal carotid avoids the bulla entirely and enters through
a foramen lacerum medium.

A CLASSIFICATION OF THE LEMUROIDEA

Order PRIMATES
Suborder Lemuroidea

Series lemuriformes

1. Malar touching lacrj^mal.

3. Orbits widely opening into temporal fossse.

3. Lacrymal foramen primitively within orbit, often secondarily in front

of orbit. Lacrymal often extended in front of orbit.

4. Nasals often retracted, rostrum more or less truncate, rarely (Chiro-

galeina?) produced.

5. Auditory bullae usually of moderate size.

6. Ectotympanic inclosed within bulla, forming a ring or horseshoe.

7. Stapedial branch of internal carotid artery typically large.

8. Main branch of internal carotid typically of small size, running in

carotid canal over the cochlea and piercing the basisphenoid.
Exceptionally entering in front of bulla (Chirogaleinte).

9. Placenta diffuse, adeciduous.

10. Digit IV of manus the longest.

11. Digit II of manus sometimes inore or less reduced.

Family Adajjidse

Dental formula: I—' C— ' P—' M— •
2 14 3

Medial upper and lower incisors broad-edged and spatulate ; medial lower
incisors more or less erect (that is, not markedly procumbent).

Lower canines caniniform; lower p, not caniniform, not opposing upper
canine.

Lacrymal not expanded on face, but lying within the orl)it; lacrymal
foramen marginal.

Brain-case but little expanded.

Sagittal and lambdoidal crests high.

Fundamental architecture of skull identical in the two subfamilies.

CLASSIFICATION OF THE LEMUROIDEA 433

BullfE and entocarotid foramina essentially as in Lemuridse.
Trochlea of astragalus narrow.
Metacarpals and metatarsals short.

Subfamily IsTotharctinffi

Lower and Middle Eocene of Xorth America.

Posterointernal cusp of m^, m-, progressively derived from anterointernal

cusp; m^ — m'' acquiring a mesostyle (in Notharctus and Telma-

lestes) ; mj^ — mg with entoconids progressive.
Genera : PelycodiLS, Notharctus, Telmalestes.

Subfamily Adapinse

Chiefly Middle and Upper Eocene of Europe (rare in upper part of

Lower Eocene).
Posterointernal cups of m^, m-, progressively derived from the cingulum ;

m^ — m^ without mesostyle; m^ — m^ with entoconids retarded,

talonids enlarged.
Forehead very narrow.
Angle of mandible much expanded.
Genera: Protoadapis, Adapis, Leptadapis, f Pronycticehus.

Family Lemuridae

Pleistocene and Eecent of Madagascar.

Dental formula: I » C— ' P— ' M —

2 1 3 3

Lower incisors styliform, procumbent ; upper incisors reduced or wanting.

Lower canines resembling the incisors.

Po more or less caniniform, opposing upper canine.

Lacrymal extended on face ; lacrymal foramen in front of orbit.

Brain-case usually expanded.

Sagittal and lambdoidal crest absent or reduced.

Angle of mandible typically slender.

Upper molars more or less ti'itu1:)ercuhir, rarely with mesostyle.

M3 with third lobe (hypocoiudid ).

. Suljfamily Lcmurinre

Size moderate.

Foramen lacerum medinm roofed over.
Posterior nares opening near or behind m-.
Genera : Lemur, Lepilemur, Mixocebus.

434 \V. K. GREGORY NOTHARCTUS AND LEMUROIDEA

Subfamily Chirogaleinse

Size usually small.

Foramen lacerum medium ("carotid foramen") open (except Myoxi-

cebus).
Palate extended to or behind m^.
Brain-case wide ; no sagittal crest.
Genera: Microcehus, Cheirogale, Atilileinur {Opolemur) , 2Iyoxicehus

(Hapalemiir) .

Sill )f ami ly jVlegaladapina?

Size very large.

Foramen lacerum medium roofed over.

Palate extended behind m^.

Skull excessively elongate.

Brain-case small, much reduced in width, witli sagittal crest.

M^ large.

Genus : Megaladapis.

Family Indrisidse
Pleistocene and Ik'cent of Madagascar.

pi p o

Dental formula: I—' C— ' Pr — x' M-^-

1 1 Z o o

Lower incisors styliform, procumbent; upper incisors usually persistent,

sometimes large.
Lower canines resembling the incisors.
Upper canines fairly large.
Po compressed opposing upper canine.
Lacrymal less extended on face; laci^nial foramen either just in front

of orbit (most Indrisinge) or marginal (PalcEopropilhecus, Avchseo-

lemuringe).
Brain-case expanded {except Pala-opropithecus) .
Angle of mandible much expanded; symphysis much prolonged and

sloping.
Upper molars large, quadritubercular ; m'^ small ; m., with third lobe

reduced or absent.
Bullae typically much expanded and completely inclosing tympanic an-

nulus (except PaJceopropithecus) .

Subfamily Indrisinfe

Medial upper incisors and lower canines small or of moderate size.
Two lower premolars.

CLASSIFICATION OF THE LEMUROIDEA 435

Outer cusps of m^, m' often V-shaped.
Skull short to long.

Bullfe normal (except in Palceopropithecus) .

Genera: Avalii { Licit anohis) , Mcsopropitheriix. Propithecus, Tndris,
Palceopropithecus.

Subfamily Arehccolcmurimu

Medial upper incisors and lower canines enlarged, diprodont, with wide,
chisel-like edges, with enamel thicker on anterior face.

'^J'hree lower preinolni's; preniohirs witlt laterally compressed bladelike
edges.

Molars more or less ])ilo})liudout.

Orbits directed forward.

A sagittal crest.

Bullae noiTTial.

Genera: Archceoleniur (Nesojjifliecus), Iladropithecus.

Family Chiromyidae (Daubentoniida^)

Eecent of Madagascar.

Dental formula : I—' C— ' P— > M— •

U i U o

Medial upper incisors and lower canines (?) much enlarged, compressed,
diprotodont, witb thick enamel on anterior border.

Upper canine, p^~^ and p^-, absent, leaving a wide diastema.

Tapper molars small : cus])s degenerate; surface of crown wrinkled.

^r^ with little or no ibird lobe.

Lacrymal very littk' extended on face; lacrymal foramen slightly in
front of crista posterior of orbit.

Brain-case expanded ; no sagittal crest.

Bulls} and course of internal carotid as in TiOmnvida' and Indrisida?.

Angle of mandible mucb reduced.

Genera: Chiromi/s ( /)aiiJ)cnfonia) .

Series lorisiformes

1. ^falar more or Ics-; sc|iai'atod froin bici'ymal hy maxillary.

2. Orbits cnlaigcd. widely opening into temjioral fossa?.

3. Ivacrymal foramen in ti'oiit of oi-hit.

4. Nasals and preniaxillaries more or less prodnced into a tubular

rostrum.

5. Auditoiy bulla) of moderate to large size.

436 W. K. GREGORY NOTHARCTCS AND LEMUROIDEA

6. Ectotympaiiic enlarged, external to bulla, forming its outer wall and

sometimes continued externally into a tubular meatus.

7. Stapedial branch of internal carotid reduced.

8. Main branch of internal carotid entering brain-case in front of bulla.

9. Placenta diffuse adeciduous (so far as known),

10. Digit IV of manus usually the longest.

11. Disrit II of manus more or less reduced.

■'to*

Family Lorisidae Gray

9 j^ 3 3

Dental formula : I^' C— ' P— ' M—-

Anterior pair of upper incisors more or less separated, of medium to

minute size.
Lateral upper incisors placed more or less laterally to median pair.
Upper canines more or less dagger-shaped; much larger than incisors

(near anterior end of tooth row).
Lower canines compressed, sharply procumbent, and incisiform.
Pm, more or less enlarged and caniniform.

Pm^ varying in form, often enlarged; Pm* bicuspid or tricuspid.
M^, M^ tritubercular with cingulum-hypocone ; no mesostyle.
Lower molars with paracone reduced or absent.
Mastoids much inflated, broadly continuous with bulla. (Mastoid sinus

in wide communication with medial sinus of bulla).
Occiput more or less flattened.

Subfamily Lorisinae

Eecent : Southeastern Asia and West iVfrica.

Climbing arboreal animals with short calcaneum and navicular, hind legs
slender and not much longer than fore legs, short lumbar para-
pophyses, and short tail. Fenmr with vestigial third trochanter.

Spines of twelfth and thirteenth dorsal vertebrae directed backward.

Spines of cervical and first dorsal vertebra elongate.

Skull strongly brachycephalic, with much widened occiput.

Orbits directed forward.

Postorbital process of malar wide.

Zygomata stout; proximal end of zygomatic branch of squamosal con-
tinuous with external auditory meatus.

Posterior nares usually behind va^.

Pm* small, bicuspid, with one external cusp ; hypocone reduced or absent.

Genera : Perodicticus, Artocebus, Nycticehus, Loris.

CLASSIFICATION OF THE LEMUROIDEA 437

Subfamily Galaginre

Eecent : Africa.

Leaping arboreal animals witli elongate calcaneiim and navicular, long

and stout hind legs, elongate lumbar parapophyscs, and long tail.

Femur with small third trochanter.
Spines of twelfth and thirteenth dorsal vertebroe directed forward.
Spines of cervical and first dorsal vertebrse short.
Skull mesocephalic.
Orbits directed more outward.
Postorbital process of malar slender.
Zygomata slender; proximal end of zygomatic branch of squamosal wholly

in front of external auditory meatus.
Posterior nares usually behind m-.
Pm* submolariform or tricuspid, with two external cusps; hypocone

present.
Genera : Galago. Hemigalago.

Series tarsiifokmes

1. Malar widely separated from lacrymal by maxillary.

2. Orbits more or less partitioned off from temporal fossie.

3. Lacrymal foramen in front of orbit.
■i. Eostrum very narrow.

5. Auditory bulla' of very large size, much extended anterointernally.

6. Ectotympanic enlarged, external to bulla, forming its outci- wall ;iii(l

continued externally into a tubular meatus.

7. Stapedial branch of internal carotid reduced or wanting.

8. Main branch of internal carotid traversing hulla from below.

9. Placenta discoidal, deciduous (Tarsiida^, ).
10. Digit III of manus the longest.

1\. Digit TI of luanus not reduced (Tar.siiis).

FMiiiily ^lici'ochoeridffi (Lydekker)

Upper Eoccnu ( ? Lower Oligoccne) Europe.

Dental for,,,,,!. : r, ^ . c^, P^-^p. m|.

Anterior pjiii- of upper iucisoi-s well scpai'ntrd, of ni('(|iuni size.

Lateral upper iiu-isoi's directly lieliiml iiie<li;iii p;iii'.

Lower iiicisoi's vestigial or aliseiit.

Upper canines \arying in size: wholly posterioi' lo incisors.

XXXIV — Bui,L. Gkoi,. Soc. \m.. Vol. lif>. 1014

4;)8 \\ . K. grp:gory — notharctds and lemueoidea

Lower canines inoi'o (Microcliceriis) or less {Nerroleinur) enlarged.

Vn\., small.

Pm* bi- or tri(U!S})id, with high external cusp, two internal cusps, and

heavy iiiteinal cinguhim.
M', M- (|iiailrilalci'al witli foiii- niaiji c-usps, large |(rolo- ;uul inelacouules,

and an acee.ssorv eonnic between Ihc protoeonc and the nietaconule ;

mesostyle present or absent.
M^ much smaller than m-, with oblique ectoloph.
Lower molars m., m^ with paraconid. absent.
Mastoids mucb inflated; mastoid inflation demarcated from bulla l)y a

constriction. (Mastoid sinus perhaps less widely opening into

bulla.)
Genera: MicrucJiwru.^. Necrolemur.

Family Tarsiidse

Lower, Middle, and I'pper Eocene, N^orth America: h'ecent, East Indies.

Dental formula : 1 1-^, C-' P^^> M--

2-0(?) 1 3-2 3

Anterior pair of upper incisors in contact, enlarged, with vertically ex-
tended crowns [l^arsius).

Lateral upper incisors ininute, posteroexternal to mediaji pair.

Lower incisors, Aarying in size, with crowns more erect tlian in Lorisida':
one or Ijoth ])airs sometimes wanting.'^

Upper canines varying in size, wholly posterior to incisors.

Lower canines sometimes enlarged, vertical or semi-procumbent.

Pni2 small or absent : pm^ lncu,spid.

Pm^ minute to absent ; pnr', jun^ bicuspid.

M^, ]\I- tritubercular, with small proto- and meiaconules; mesostyle
rarely present : hypocone small to al^sent.

M^ tritubercular.

Lower molars tuberculo-sectorial, witli small, Jiigli (rigonid and low
talonid. Paraconid present ty])ically well developed.

Mastoids not or but little inflated: occijnit well rounded.

Placenta discoidal, deciduous (Tardus).

Genera: Tetonius, SJioshonius, Anapfomorpliits, Lower Eocene; Oino-
mys, Hemiacodon, Washahiufi, Middle Eocene; Uinfanius, Upper
Eocene ; Tarsius, Recent.

' In certain Lower Eocene forms recently described by Doctor Matthew, op. cit.

PHYLOGENETIC SUMMARY 439

PHYLOGENETIC SUMMARY

Xearlv all known gen-ra of recent and fossil leiuuroids have been
studied by tlie writer v. itli sjiecial reference to the basicranial region,
dentition, and limbs. It is proposed to divide the suborder Lemuroidea
into three major groups or series — the Lemuriformes, the Lorisiformes,
and the Tarsiiformes.

Of the Lemuriformes, bv far the most ])rimitive is the subfamily
Notharctinffi of the family Adapida?. This subfamily first appears as
small insectivorous forms of the genus Peh/codus in the Lower Eocene
of North America. These have the primitive dental formula of

2 14 3

I — ' C— ' P— ' M— and siiiir)le ti'ituhercular molars. The next stage, A"o-
z 1 4 3

flmictus-. with ((uadrituhercular molar teeth, is well known in the skull and

most j)arts of the skeleton. The sul)family terminates in the relatively

large and piogressive genus TeJniah'sles of the Tapper Bridger formation.

Kxcept for cei'tain details of the molars, the Xotharctinjie appear to be

sli iicturaliy ancestral to all the higher Lemuriformes.

Ill iMirope the true Adapiiue are said to appear in the upper levels of
the Lower Eocene, but are moi'e abundant in the ^[iddle and L^pper
Eocene. The Ada])ina' aie closely related to the earliest Notharctinae,
bat rollew' a diifei'ent tiend of evolution of the molars. The best known
genus. Adiijiis, is evidently a s])ecialized side branch; lint Pronycticehus
(Trandidiei', whieli. in tln' \\i-itei'"s judgnieid. sliould be referred to the
Adapiiiie, has tlie expected charactt'i-s of the hasicranium, dentition, and
general skull chai'acters for an ancestor of ihi' lemurs of Madagascar.

The laltei' constitute all the existing blanches of the Leinnri foi'ines
and include three families — the Lemurida', the Indrisida?, and the Cbii-o-
myida-. These three families seem to ha\e sprung from a common stock
which eiilerecl .Madagascar perhaps in Oligocene times. The earliest
ti'ue leiiiiirs prohably liiid ;i fairly sIkh'I face and large orbits, a wide
basicraniiini and expaiideil hidhe: the upper molars mav lunc heen lil<e
those of I'roni/rl II chiis. namely. 1 rit ultercu la r, with a |)roiiiineiil cingii-
lum-hypocoiie : ihr lower incisors and canines were partly procumbent,
pill' and pin, were small or aliseiit, the jaw was fairly siiort and deep
with a large angle. Clieiroi/d/nis of the mouse lemurs has retained most
of these |)riiiiili\e characters.

'I'lie varied descendants of this relatively high type exhibit diver.se
(omliinat ions of ictrogressixc and progressive changes.

In Mc(/(il(i(f(i/tis, for example, there was an extremely rapid increase
in size of body and in the length hoth of the face and of the brain-ca,so.

440 ^\■. K. GREGORY NOTHARCTUS AND LEMUROIDEA

with a ivliiii\c mliR-tioii ill size of the orbits and of the volume of the
lu-aiii: 111 MIrrarcbn.s, on the contrary, there may have been a dwarfing
,,r li(.(l\ size, a -ivat widening of the brain, a reduction of tlie face, and
ill! ,.|ihii-viiiciit (.r the orbits. In many lines the lower jaw orcw lon^-
and weak, tiic alible slender: the lower incisors and canines became small,
l.rociimlM'iit ami compressed: the muzzle was often widened: the upper
incisors weiv rechiced; the opposite tootJi rows straightened. The molars
were tlivci-sely modified, some becoming blunt-cusped with low, round
cingulmii. others becoming sharp-cusped with cuspidate cingulum. The
limbs and extremities, which were primitively short, as in Lepilemur,
either grew long and slender, as in Microcehus, which has the tarsus
variously elongate, or stout and relatively short, as in the hind limb of
Megaladapis. Tlie writer is convinced that changes in the direction of
evolution involving reversal of proportions, such as large orbits changing
into small orbits, expanded bullae becoming deflated, and the like, have
been frequent in the history of the Lemuroidea.

The Indrisine lemurs, or Indrisidse, constitute a very well marked
Malagasy group which may have been derived from a form like Proni/rii-
rehm of the Adapina3 by the expansion of the orbits and brain-case, very
marked shortening of the face, great deepening of the lower jaw and its
angle, and crowding out of two premolars above and below on each side,
namely, pmV, pm" and pm^, pnig ; at the same time the upper molars
became elongate anteroposteriorly ami the cingulum grew u]) into a large
hypocone in adaptation to leaf- and fruit-eating habits. The basicranium,
including the bullfe and the course of the internal carotid artery, were
fundamentally similar to those of the Ada})id[e and Lemuridge, and the
same is true of the backbone, limbs, placentation, and brain. This primi-
tively central and relatively high type is most nearly realized in the
existing genus Avahis, which has, however, further expanded the brain
and orbits. A retrogressive series leading in a general way througli
Mesopropithecus and Indris ends in the highly aberrant and misnamed
PalcepropitJiecus — a gross and swinelike animal, with a thick muzzle,
small eyes, deflated bullfe, and a low brain-case. Al)oiit i\\Q only feature
ill whicli Palceprqpithecus is not degraded is the extreme depth of its
lower jaw, in which it surpasses all the otker Indrisinse.

Tn the opposite direction a progressive series, in which only the ter-
minal memljers are known, has led from tlie primitive Indrisine to the
apelike NesopUlmcns (Archceolemur) and the still more advanced Uadro-
pWiecus. These forms, by reason of their large brain-case, forwardly
directed orbits, and macaque-like molar teeth, have given rise to the
preposterous liypothesis that they indicate a special affinity between the

PHYLOGENETIC SUMMARY 441

Indrisida^ and the Anthropoidea ; Init in all their palseotelie characters,
especially of the hasicraninni, the Archaeolemurina^ are truly Indrisine,
as Elliot Smith has also observed in their brains.

From some early member of the Archasolemurinas sprang the aberrant
Chiromys (Dauhentonm). This genus exhibits a rodent-like modifica-
tion of the Indrisine type. Its lower front teeth are probably not in-
cisors, but procumbent canines. Its gruli-eating habits are reflected in
the degenerate character of the cheek teeth.

The second grand division of the Lemuroidea, as here classified, is
named the Lorisi formes, comprising the existing Lorisinse of Asia and
Africa and the Galaginae of Africa. The members of the Lorisiformes
combine the characters of the Lemuriforaies and of the Tarsiiformes in
a manner suggesting extensive parallelism with these groups. All the
Lorisiformes resemble the Lemuriformes in the lemur-like modification
of the incisors and canines. All show special resemblances with the
mouse lemurs in the manner in which the internal carotid artery enters
the brain-case, and some further parallel the mouse lemurs in the length-
ening of the tarsus. Nycticehns of the Lorisiformes is known to have
the placenta diffuse and adeciduous as in true Lemurs. On the other
hand, the Lorisiformes parallel the Tarsiiformes in the fact that the
ectotympauic, or tympanic annulus, instead of being completely covered
over by the bulla, as in the Lemuriformes, forms its outer margin, as in
the Tarsiiformes. The Galagos further parallel Necrolemur of the
Tarsiiformes in the form of the occiput and in the expansion of the
mastoid region, 'i'lic correct phylogenetic evaluation of these conflicting-
resemblances to tlie I.emuriform and Tarsiiform groups is still doubtful,
l)ut I incline in ihi' opiiiioii tliat tlie Lorisiformes are, on the whole, more
nearly alliiMl \n the Lciiiiiiiroi'ines ; that they may have come oflF from
some siiili ,111 A(la|ti(l as rnnnicficrhiis. as suggested by Grandidier. and
lliat the Iciiglliciiiiig of the tarsus, (exposure of the ectotynipanic, and
inflation nf the mastoid has occurred independently in the Lorisiformes
and 'I'arsii roi-nics.

Tarsiiformes. — The tliiid and last great group of the Lemuroidea in-
cludes not oidy the existing Tarsius, but also the American Lower, Mid-
dle, and L])j)ci' Eocene "Anaptomorphidse" and th(> P]uropean Upper
Eocene Microchwrus and Necrolemur.

Even in llic Lower Eocene of Morth America there were genera witli
large oi'ltil>, \rry nari-ow niuzzli'. and wide, round brain-case, wliidi
appear e.\1 1'cnic I y niodiTnizcd for such ancient types. The skull structure
of these Anaptonioiphida' is best known from a famous specimen named
by Cope Anaptoinorithus liniiiiin(ulu.s: Piirther development of the basi-

442 W. K. GREGORY NOTHARCTUS AND LEMUROIDEA

cranial region of this specimen lias served to emphasize its resemblance
to Tarsius, especially in the formation of the bulla and in the pattern
of the cheek teeth. It is, however, far more primitive than Tarsius in
haviiiir a much smaUer cochlea, or auditory prominence, a less expanded
bj'aiii-easc, and smaller orbits. Its Middle Eocene relative Omomrjs is
extremely like Tarsius in the cheek teeth, as noted by Wortman, and, in
the o])inion of J)()ctoi' Matthew and the writer, it is so difficult to sep-
ai-ate the Anaptomorphidte and the Tarsiidse as distinct families that we
prefer to unite them in a single family — Tarsiida?.

IMie LoM'er Eocene members of the Tarsiiformes were thus rather
widely different from the contemporary Lemuriformes of the family
\otharctina\ Erom the characters of the jaw and dentition in the
earliest Notharctina? it seems right to infer that the general architecture
of the skull was not dissimilar to that of NotJimrtus. This differs widely
from " Anaptomorplius" in having a relatively narrow, unexpanded brain-
cast', a far larger face, and smaller orbits. These features may have been
h'ss ])ronounced in the earlier Xotharctina?, while the opposite Tarsiiform
characters may have been less pronounced in some of the other Lower
Eocene genera of the Anaptomorplms group; but still the contrast l)e-
tween the representatives of the Lemuriformes and Tarsiiformes must
have been sufficiently great in the Lower Eocene to Avarrant us in looking
for the common stem form of the Lemuroidea in the Paleocene or even
earlier.

Mkruclmr'uUr. — A study of several excellently preserved skulls of
Nerrolemur shows that the basicranium closely resembles that of Tarsius
ill many respects, especially the mode of formation of the bulla?, character
(>r the glenoid, position of the cranial and carotid foramina; so that, in
view of further evidence offered by the facial region and dentition, refer-
ence of Necrolemur to the Tarsiiformes seems well warranted. On the
other hand, Necnilninir has more complex sexitubercular upper molars
than any of the Anapt(jinin-/)]i us-Tdrsiiis group, and its nearest affinities
ai-e undoubtedly with M i( roi Im-nts. as suggested by Eorster Cooper: but
iieitlief of these genera have anything to do with the Hyopsodontidai,
with which earlier authors placed Microchoerus.

The relationships of the Tarsiiform series oji the one hand to the
Mici'osyopsida^ and on the other to tlie Anthropoidea seem at present
hio-hlv doiihtful.

'fe

bibliography 443

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444 W. K. GREGORY NOTHARCTUS AND LEMUROIDEA

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ceux qui viva lent ;i Madagascar. Extrait des Nouvelles Archives du Mu-
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W. K. Gregory : Tlie orders of mammals. Bulletin of the American Museum
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: Relationship of the Tupaiidje and of Eocene Lemurs, especially No-

tharctus. Proceedings of the Geological Society of America, Volume
XXIV, 1913, pages 247-252.

: Exhibition of a fossil skeleton of Notharctus rostratus, an American

Eocene Lemur, with remarks on the phylogeny of the Primates. Report
of the British Association for the Advancement of Science, 1913, pages
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A. A. "W. HuBRECHET : Descent of the Primates. 1897.

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of Philadelphia, pages 113-114. October, 1870.

R. Lydekker : Catalogue of the fossil Mammalia in the British Museum ( Nat-
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to the Erinaceidte."]

Major C. I. Forsyth : uber die Malagassischen Lemuriden-Gattungen Micro-
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■: On Lemur mongoz and Lemur ]'ul)ivente]'. Proceedings of the Zoolog-
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: On some characters of the skull in the Lemurs and Monkeys. I'ro-

ceedings of the Zoological Society of Ijondon. Volume I, number ix, 1901.
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O. C. Marsh : Notice of some new fossil mammals from the Tertiary forma-
tion. American Journal of Science (3), Volume II, 1871, pages 35-44.
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: Discovery of fossil Quadrumaua in the Eocene of Wyoming. Amer-
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[Limnotherium referred to Quadrumana.]

—— — : Notice of new Tertiary mammals. IV. American Journal of Science

(3), Volume IX, 1875, pages 2.39-250. [Limnotheridse proposed, page 239.]

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BIBLIOGRAPHY 445

Hyopsodontid.ne. By W. D. Matthew. Bulletin of the American Museum
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W. D. Matthew : Climate and evolution. Annals of the New York Academy
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: Contributions towards a more complete knowledge of the axial skele-
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: Additional notes on the osteology of the Lenuirichp. Proceedings of

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Max Schlosser : Die Affen, Lemuren, Chiropteren, lusectivoren, Marsupialier,
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Part II. Number I, 1908, pages 59-162.

H. G. Stkiilin: Die Siiugetiere des schweizerischen Eocaens., VII Teil, erst
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446 W. K. GREGORY XOTHARCTUS AXD LE:MrROIDEA

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BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA
Vol. 26, pp. 447-476, PLS. 25-27 DECEMBER 4, 1915

PROBLEM OF THE TEXAS TEllTIARY SAXDS '

BY E. T. DUMBLE

(Bead before the Socief;/ Aui/usI ■">. IDhl)

CONTENTS

Page

Introduction 447

Review of previous worl-c 449

Recent examinations- 457

Descriptions of formations of east Texas 459

Lower Claiborne 459

Yegua 459

Fayette 460

Frio » 461

Upper Claiborne , 461

Jackson 461

Corrigan 465

Fleming 467

Summary ., 473

Possible equivalency 476

Introductio.\

In connection with the Oulf Tertiary deposits, which stretch entirely
across the Coastal Plain of Texas, there is a narrow helt within which
the outcrops of several distinct sandy formations are exposed. The shore-
ward margin of this belt averages about 100 miles from the present Gulf
coast. The belt is sometimes less Ihnii l<i miles in width, very rarely
widens to more than 20 miles, and reaches its broadest exposures of about
40 miles only on the Xueces and iiio Grande.

There are five of these sands. They are very similar in composition
and appearance, fossils are comparatively rare in them, and it is often
diillcult to distinguish the one from the other, especially where the sands
of one division overlap and ai'c in liircct contact with another.

These sands, in descending order, are :

'Manuscript rocoivcd by Iho Socrotary of tlio Socloty Octobnr 1.3, 101."..

(447)

448

7':. T. DIMBLE PROBLEM OF TEXAS TERTIARY SANDS

THE SANDS AND ORDER OF OCCURRENCE 449

Lapara (Dumble),- carrying in the ISTueces section vertebrates determined

by Cope to be of Blanco Pliocene age.
Oakville (Dumble)/ with vertebrate fossils determined by Cope to be of

Loup Fork Miocene age. Plant remains uiistudicii.
Catahoula (Veatch)/ continuation of bods in Louisiana and carrying

plant remains. Oligocene.
Wellborn (Kennedy)/ with marine invertebrates which Harris referred

to the Lower Claiborne, and were, therefore, correlated by Kennedy

with the Fayette, but which Vaughan''' now considers Lower Jackson.

Middle or Upper Eocene.
Fayette (Dumble)", with marine invei'lebrates determined by Harris and

referred to Lower Claiborne. IMant remains unstudied. Middle

Eocene.

So far as known, there is no place within the belt where all of these
sands are present, unless it be on the Colorado Eiver.

On the Rio Grande the Fayette is overlain by the Frio, and this by the
Oakville. There is no evidence of the Catahoula.

On the Sabine, while the Oakville may be present as such above the
Catahoula, no evidence has yet been found of either the Wellborn or
Favette beneath it.

In the region ])etween, other conditions prevail, and this has led to such
confusion that it seems best to bring togethei' what has been done in order
to clear away, as fai- as possible, the misunderstandings that have arisen
iiiul open tlie ro;i(l foi' the final solnlion of the problem.

Review of i-revious Work

Hilgard,'* who made a geological I'cconnaissance of Louisiana in 1869,
visited some localities in east Texas, where he found the extension of his
Grand Gulf beds. These he described and referrcfl to that age.

Loughridge^ reports that this belt of sandstone, beginning on the Sa-
bine, in the lower part of Sabine County, outcrops on the Trinity near
Trinity station, near Chapel Hill and Burton, at La Grange Bluff, at
Hellgate Ferry near Cuero, and then forms a line of hills, via Oakville,
southwestward thniuoh |)u\al Cnuiitv lo tlie Rio Grande at Rio Grande

^Journal of Geologj-, Sept., lS'.t4, \>. .">.".0.

3 Journal of Geology, Sept., 1804, p. 55G.

* U. S. Geological Survey Prof. Paper 4(5. p. 4:.'.

'' Fourth Ann. Repl. Geol. Surv. Texas, p. 4.").

' U. S. Geological Survey Water-supply Paper No. ."..'io. p.

^ Journal of Geology, Sept., 1894, p. 552.

» Am. Jour. Sci., 2d sor., vol. 48, 18B0, pp. :'..!7-."..'!S.

» Cotton Production, Tenth Census, p. 21.

450 E. T. DlMl'-LK PROBLEM OF TEXAS TERTIARY SANDS

City. He describes the rock as coarse-grained or conglomerate, with
wliite siliceous clay as a cementing material. He notes the lack of fossils
and states that it has been referred to tlie Graiid Gulf, of probably
Miocene age, for stratigraphic reasons.

Outside of tbe Sabine, Trinity Kivcr, and Burton outcrops, all of the
localities mentioned by Loughridge are occupied by exposures of the Oak-
ville or Lapara sands of the present classification.

Penrose," who studied these sands by boat trips down the Colorado,
Brazos, and Eio Grande, used the name Fayette to designate the entire
series of deposits lying "between the uppermost fossiliferous strata of the
marine Tertiary and the post-Tertiary." In this he followed the example
of Hilgard, and he, furthermore, correlated his Fayette with the Grand
Gulf of that author. The Fayette of Penrose did not include the Orange
sand or Eeynosa (Lafayette).

On the Colorado, which was first tra\ersed by Penrose and made the
basis and type of this division, his Fayette begins near the county line
betM^een Bastro]) and Fayette counties, where the last fossiliferous beds
were found in White Marl Blufi^. Its base consists of dark clays with
lignites, as seen on Barton Creek, followed by light-colored, sulphur-coated
clays and sands, forming bluffs on the river and becoming more clayey
toward the top, and his description closes Avith the Iduf! of somewhat
similar materials south of La Grange.

On the Brazos, similarly, the Fayette beds, as described by Penrose,
begin below Mosely Ferry, where the last Eocene fossils were found, and
have at the base gray sands and chocolate clays with lignite beds, followed
by light-colored sands and clays to the Houston and Texas Central cross-
ing near Hempstead.

Carrying out the same basis of division, the description of the Fayette,
of the Rio Grande begins with the clays overlying the last fossil-bearing
beds of the Eocene near Eoma, and includes the sands at the base of the
section near Eeynosa. Doctor Penrose, however, recognized the close re-
semblance of the light-colored clays and sands, with Ostrea alahamiensis
var. confracfa (0. georgiana ? of Penrose report), occurring north of
Eoma, to those of the Fayette section. ^^

A year or two later it was found that the body of dark-colored clays
with lignite, which formed the base of the Fayette division of Penrose,
carried a marine invertebrate fauna in tlieir exposures in branches of the
Yegua. As these fossils pro\ed to be of Lower Claiborne age, these clays

10 First Ann. Kept. Geol. Siirv. Texas, p. 47 et seq.

li First Ann. Rept. Geol. Surv. Texas, p. .56. These are included in tbe Fayette beds
of our present classification. Geol. S. W. Texas. Trans. A. I. M. E., vol. 33. p. 969.

REVIEW OF PREVIOUS WORK 451

were separated I'rum his Fayette and added to Ins Marine beds under
the name of Ye^ia clays. ^-'

During 1892-1893 Harris studied the gTeat mass of Tertiary inverte-
brate material that had been collected by various members of the Texas
Survey and prepared a report on it^^ that would liave been of gi'catest
value to all workers in Tertiary geology. Unfortunately a wave of econ-
omy struck the State administration about that time, and, together with
the other papers which were to make up the Fifth Annual Eeport, its
publication was held up. Fortunately he had made a very complete
catalogue of species and localities, and this is preserved at the University
of Texas.

The collections made by Penrose and Bumble from the Fayette sands,
exposed on the Eio Grande between Zapata (Carrizo) and the northern
line of Starr County, were studied and the following forms determined :"

Ontrca alnhnmUnHift var. contractu Volutilithes petrosa

Con. Pscudoliva vetusta

Anomia ephippioidcs Gabb Pscudoliva vetusta var. pica

Pcctcn sp. a Pscudoliva vetusta var. fusiformis

Lcda opulent a Lcvifusus tfabeatoides

Venencardia planicosta Lam. Cornulina armigera

Crassatella protexta Turritclla nasuta

Ciitherea sp. a Turritclla nasuta var. houstonia

I'ijthereu bastropensis Har. Natwa sp- b

Tellina sp. Natica .sp. c

TelUna moorcana Natica rccurva var. dumhlci

Scmcle liHttsd Lacinca alvcata

Volutilithes sp. Conus sauridcns

Xo fossils except oysters were found in the upper portion of the section
lying between tlie Starr County line and Eoma, and it was in this stretch
that all of the larger oysters were found. The lower beds, between Zapata
and the Starr County line, which furnished all the other species of fossils,
carried oidy medium-sized oysters, althongh they were identified as be-
longing to same species.

The abundance of inxci'lchratr lussiis in this region is in striking von-
trast to thr cninliiions on llic Colorado, where only plant remains have
been observed.

The section on the Nueces River showed the Fayette sands overlying
the Yegna ehiys and o\ei-!ain by a body of dai'k-colored calcareous clays,
which were caileil the Vy\o clavs.

'= Hrown : Coal and liKnil*'. P- 1-18.

'■' Ilai-fis : Manuscript record of Tertiary fossils.

'* Harris : Manuscrii)t record of Tertiary fossils.

452 E. T. 1)1 MBLE PROBLEM OF TEXAS TERTIARY SANDS

Duinble's collections from the sands in the jSTueces Eiver section, em-
i)racing five localities near Lipan Creek, below Campbellton, yielded:

Ostrca ulahamicnsiH var. contracta Corhula aldrichi

Modiola texana Corhula sp. a

Vcncricnrdia planicosta HiateUa sp.

Ci/thcrca hastropensis Turritella nasuta

Cythcrca sp. a • I'scudoliva vctusta

TclUnn scandula ConiuUna armigera

Mactra sp. Terehra houstonia

Corhula alabaniiensis Levifusus traheatoides

Harris, on the basis of these collections, referred these sands to the
Lower Claiborne.

The Frio furnished very few fossils, and those gave no hint of any
later age than that of the Lower Claiborne.

Overlying these Frio clays was an extensive body of sandstones, to
which the name Oakville^^ was given. On tracing, these appeared to be
the same sands that occur at Eio Grande City and in La Grange Bluff.
Vertebrate fossils found at various places determined their age as Loup
Fork Miocene.

Overlying the Miocene Oakville sands on the Nueces we found another
series of similar sands with vertebrate fossils. These were determined
by Cope as Pliocene and as of the same horizon as the Blanco beds of the
Staked Plains region. These were called Lapara. These were followed
by greenish gray clays which carried Plioc-ene fossils, but were later than
the Lapara. These were called the Lagarto.

The name Fayette sands was then restricted to those sands and clays
of the original typical sections, which, with their light colors, sulphur
coatings, quartzite bands, petrified and opalized wood, were most promi-
nent in the earlier descriptions of Penrose and which had become most
closely associated with this name in the minds of those working on the
Texas Survey.

We have, therefore, in southwest Texas three sands which, while similar
in character, are clearly differentiated by their fossils as Eocene, Miocene,
and Pliocene in age.

Where we find the Oakville sands overlapping and resting upon the
Fayette, or find the Lapara in direct contact with the Oakville, as is
often the case, it is sometimes difficult, because of their similarity, to
separate them, unless fossils are present, and such conditions may inter-
fere with their being accurately mapped as separate fonnations.

The typical sands at Grand Gulf, to which Wailes' name of Grand Gulf

^ Journal of Geologj% 1894, p. 552 et seq.

REVIEW OF PREVIOUS WORK 453

sands is now restricted (jvist as we have restricted the name Fayette
sands to those of the typical Colorado and Eio Grande sections), are of
Oligocene age, and therefore are not represented by either the Fayette,
the Oakville, or the Lapara sands. It is true that there are points of
resemblance in these sands to those of the Grand Gulf, especially in the
quartzitic beds and the opaline cement, besides which the Fayette, in
places, carries some plant remains.

In the Nueces section the Oakville includes a body of brown sands at
its base in which no fossils were found, and it was recognized that further
study might necessitate a separation of this from the upper fossiliferous
beds;^® but, so far as is now known, there is nothing to indicate its con-
nection with the Grand Gulf or Catahoula or to remove it from the
Miocene.

The physical conditions on the Eio Granele and Nueces appear to ex-
tend eastward to the San Antonio River. East of that stream the Frio
gradually becomes thinner, and is almost, if not entirely, lacking on the
Colorado. Both the Fayette and Oakville show a greater admixture of
clay, and the invertebrate fossils so abundant on the Rio Grande seem
entirely wanting and are replaced by fossil plants.

East of the Colorado the difference is even more marked.

In 1891 a few imperfect casts of fossils were found at what was sup-
posed to be the base of the Fayette sands,^'^ near Sunnyside, in Lee County.
Later better specimens were found, and Harris determined them as
follows :

Ceronia singleyi Pleurotoma moorei var. g

Paphia ~

Kennedy, in his East Texas sections,^^ describes the sands in the vicinity
of Corrigan and Rockland. In a railroad cut 4 miles north of Corrigan
he collected the following forms from the base of these sands :^^

Dcntalium microstriatum var. dumblei Pleurotoma quassalis

Venerwardia planicosta Turhonella sp.

Cytherea texacola var. tornadonis Lcvifusus trabeatoides

Corhnla alabamiensis Cancellaria penrosei
Cah/ptraphorus velatus

These sands carried opalized Avood similar to that of the Fayette west
of the Brazos and showed similar quartzitic masses. They were referred
to the Fayette.

" Diimblp : GpoI. S. W. Tex. Trans. A. I. M. R., vol. S."^, p. 076.

"Third .\nn. Hept. Geol. Surv. Texas, p. xxiii.

" Kenned.v : Third Ann. Rept. Geol. Surv. Texas, p. 115.

** Harris : Manuscript record Tertiary fossils.

XXXV — Bull. Geol. Soc. Am., Vol. 26, 1014

454 E. T. DUMBLE PKOBLEM OF TEXAS TERTIARY SANDS

The clays overlying these Corrigan sands he called the Fleming beds.

Til his work in Grimes and Brazos counties, Kennedy-^ found two series
of sands, the lower of whic-li he called the AVollborn sands and correlated
with the Fayette sands. He made the other the basal member of his
Navasota beds. Fossils were found at Williams quarry, in the Stephen-
son league, east of Wellborn, near the base of the Wellborn sands. They
were as follows :-^

Yoldia claihornensis Corbula alahamiensis

Venericardia planicosta Turritella sp.

Cytherea 'bastropcnsis Cancellaria penrosei

Siliqua simondsi Plcuroionia qiiassalis

Mactra sp. a Cylichna kcllogii

No fossils were found in the ISTavasota sands.

In the section along the International & Great Northern Eailway the
sands between Riverside and Huntsville were supposed, on account of
lithologic resemblance and the number of palmetto leaves they carried,
to represent the Oakville sands, and the overlying clays between Hunts-
ville and Willis were, on stratigraphic and lithologic ground, correlated
with the Lagarto. The clays underlying the Oakville at Eiverside were
thought to be Frio.--

In 1895 Kennedy, in an article on "The Eocene Tertiary of Texas east
of the Brazos River,'' -^ correlates his Fleming beds south of Corrigan and
around Woodville, Tvler Countv. witli tlic Frio clavs of west Texas and
the underlying "Corrigan" sands, including tliose at Stryker, Corrigan,
Lovelady, and Wellborn, with tlie Fayette. Speaking of the plant re-
mains of these sands, he says :^*

"Palm wood is plentiful, while the stems and leaves of the palmetto, rushes,
and marsh-grass may be found in some localities in abundance, showing that
when these beds were being deposited the marshy tracts of the Yegua clays
to the northward were .still the home of such growths. None of these are
Indigenous to the Fayette sands and exist there only in the form of drift
material cast up by the sea. Near the top of the Fayette (Corrigan) sands
we find trunks and limbs of trees of large size, many of them even now show-
ing diametric measurements of over 3 feet; and although some show a length
of 25 or .30 feet, the greater portion of the logs do not exceed 10 or 12 feet in
length. Occasionally a stump with the larger roots attached may be found,
but this is exceedingly rare- A peculiarity regarding these trees is that they

2« Kennedy : Fourth Ann. Rept. Geol. Surv. Texas, pp. 9-40.
Eocene-Tertiary, Phil. Acad. Nat. Sci., 1895, p. 9.5 et seq.
^ Harris : Manuscript record Tertiary fossils.

22DumbIe: Notes on Texas Tertiarles, Texas Acad. Sci., 1894, p. 25.
=» Trans. I'hil. Acad. Nat. Sci., 1895, pp. 84-160.
2* Op. cit, p. 159.

REVIEW OF PREVIOUS WORK 455

are every one in tlie form of wood opal or in an opalized condition, vitreous
and clear when broken, breaking with sharp cutting edges, and retaining every
mark and line of growth as it appeared in the tree. The outside of these
woods is generally a dull white, showing a process of decay. This form of
wood is peculiar to the Fayette (Corrigan) sands and occurs nowhere else
within the Texas regions."

Dumble/^ describing the section along the Texas & New Orleans Bail-
way between Beaumont and Rockland, refers the clay beds around Wood-
ville, described by Kennedy-*^ as Fleming, to the Lagarto on account of
their stratigi-aphic position and lithologic resemblance. The contact of
these Lagarto clays with the underlying Oakville was described as cross-
ing the line of road 21/2 miles south of Eockland. The Lapara was not
recognized in this section.

Veatch, in connection with his investigations of the water resources of
Louisiana and Arkansas, studied the geology of a portion of eastern-
Texas. Examining the beds-' 4 miles north of CoiTigan, he found, in
addition to the fossils collected by Kennedy, a number of others which
made necessary the reference of this portion of the beds to the Jackson.
These included :^^

Levifusus 'branneri Maszalina var, oweni

Just below Robinsons Ferry, on the Sabine River, he foimd the Jack-
son clays well exposed. Two other fossiliferous beds are noted farther
down the river. He also mentions Jackson fossils near Caddell and large
bones (probably Zeuglodon) east of the Sabine, on Caney Creek.^^

The sands immediately overlying the Jackson, beginning just south of
Piney Creek and extending south of Corrigan to Moscow, he refers to
the Catahoula, which, as shown by the geologic map accompanying his
report, also includes the sands at Rockland.

He states that, in order to furnish a name not likely to be misunder-
stood,^" the name Catahoula formation is \ised as a synonym for the
"typical Grand Gulf,"' or the "Grand Gulf proper," which immediately
overlies tlio Yicksburg and is of Oligocene age. East of the Mississippi
the sands a])parently gi-ade into the Chatalioochee group of sands and
clays.

He also describes the Fleming clays of KouDcdy which overlie his
Catahoula, and since no marine fossils were IouikI in them except near

^Dumble: Disc. Lucas Well. Trans. A. I. M. E., 1001. vol. :U, p. 4031.

-■" Kennpfl.v : Thli-tl Ann. Ucpt- fieol. .Surv. Texas, p. (;:.'.

=7 Voatcli : U. S. Geological Survey Prof. Taper No. IC. |i. :!0.

^Harris: Ct-ol. Surv. Louislan:!. 1002. p. '-!.">.

=» Veatcb : Geol. Surv. Louisiana, 19012, p. 130.

*>Veatcli: U. S. Geological Survey Prof. Paper No. 40, p. 42.

456 E. T. DUMBLE PROBLEM OF TEXAS TERTIARY SANDS

Biirkeville, Newton County, "where a brackish-water Oligocene fauna has
been found," lie correlates the Fleming beds, as well as most of the Cor-
ligan sands, with the Oligocene.

This discovery of Jackson fossils l)y Veateh seemed to cast a doubt on
Harris' earlier correlation of the Corrigan sands with the Fayette and
an effort was made to get the facts. It was found that there was a body
of sand crossing the line of road south of Burke^^ about where the Fayette
should be, but that there was no distinct exposure on the railroad, along
which Kennedy made his section. Other detacbed exposures were found
east and west of the line, one of the priiuipal ones being at the town of
Homer. These sands and white clays overlie the Yegua and are very
like the Fayette, and while no fossils were found, we were re'asonably
certain that they did represent the true Fayette in this region and these
exposures were supposed to represent the outcropping edges of the main
body of sands. The clays in the valley of the Neches apparently over-
lying these sands were therefore thought to be Frio.

Harris follows Veateh in referring the '^'T4rand Gulf l)eds jiroper" and
the Frio clays, as he terms Kennedy's Fleming beds, to the Oligocene."-

Deussen embodies the result of his examination of this region in
his report, "Geology and Underground AYater-sup^jly of Southeastern
Texas." 3"

From this report and the geologic map accompanying it, it would
appear that he limits the Jackson proper to a narrow lens of calcareous
fossiliferous clays containing large limestone concretions which extend
from the Sabine Eiver to Burke, on the Houston, East & AVest Texas
Railway. The surroimding sandier beds he calls the Catahoula, using
the name in a much broader sense than Veateh gave it, to include every-
thing (except the small belt of Jackson clays already referred to) be-
tween the Yegua clays and the Fleming clays from the Sabine Eiver to
the Colorado. This is modified, however, in a footnote^* stating that
later studies indicate that the Catahoula sandstone, described in his re-
port as a stratigraphic unit, really comprises two formations of similar
lithologic character, the one at the base being of Jackson age, whereas
the upper sandstone is of Oligocene age. The lower of these sandstones
includes the Wellborn sands of Kennedy.

With regard to the age of the Wellborn beds. Deussen savs :^^

"Vaughan is of the opinion that the horizon represented by the hard fcs-

31 Dumble : Science, vol. 16, 1902, p. 670.

«2 Harris : Geol. Surv. Louisiana, 1902, p. 28.

^ U. S. Geological Survey Water-supply Paper No. .S35.

2* Op. cit., p. 70.

35 Op. cit., p. 72.

REVIEW OF PREVIOUS WORK 457

silifei-ous sandstone on the Robert Stephenson league is probably very low in
the Jackson ; and, if this be so, the beds between Wellborn and Millican would
represent in part the time equivalents of the Jackson formation along the
Sabine."

His use of the Catahoula makes it cover the locality 4 miles north of
Corrigan, at which Veatch found his Jackson fossils.

Tlie inference is, therefore, that he considers all of the beds from the
lojD of the Yegua to the base of his up2:)er or Oligocene sandstone as
referable to the Jackson.

The report describing the Fleming clays refers them to the Miocene.
In connection with this, Matson gives Ball's determination of the Burke-
ville fossils and his reference of them to the Pliocene.

Deussen, untler the name Dewitt, includes the Oakville, Lapara, and
Lagarto of Dumble, and shows them overlying the Fleming clay. A
footnote suggests that on the Sabine the Dewitt is represented by the
Fleming clay.

Recent Examinations

In connection with the investigation of the oil fields of the coast region,
wliicli has been carried on under the direction of the writer, there has
iieen occasion to study these sands at various places, and some of the
information oljtained and heretofore unpublished has a direct bearing on
this subject.

During 1904 Hager endeavored to trace the lower contact of the Oak-
ville beds from the Nueces to the Sabine, his identifications of it Ijeing
based largely on the lithology of tlie l)eds.

On the San Antonio Eiver he found the contact about 3 miles south
of Helena; on the Guadalupe near the mouth of Barton Creek, 10 miles
southeast of Gonzales; near Flatonia on the Galveston, Harrisburg & San
Antonio Railway; 3 miles north of La Grange; on the Brazos 5 miles
west of Xavasota; at Riverside on the Trinity; three-quarters of a mile
south of Corrigan; 1 mile south of Rockland, and on the Sabiiie about
1 mile north of Bun-^s Ferry, northeast of Burkeville.

West of the Guadalu])e lie notes the presence of the Frio immediatelv
underlying the Oakville, but thinning toward the northeast. He incii-
tions its absence on tlio Colorado and eastward of that stream, all of tlie
contacts observed l)ciiig described as with the Fayette or Eocene sands.

He thus descrilics iho Oakville beds cast of the Brazos:

"On the Brazos the Oakville beds may best be described as cemented sands.
They consist of fine white sands, with some clay, firmly cemented into a white
mass by calcareous mateiial. They contain some gravel, silicified wood, and

458 E. T. DUMBLE PROBLEM OP TEXAS TERTIARY SANDS

numerous rolled Cretaceous fossils. Ofteu they form thin-bedded, jointed,
irou-stained calcareous sandstones.

"Toward the east their character gradually but materially changes. They
become more ferruginous, and their cemented condition is less marked. The
sand occurs more often in a loose condition. Small black land prairies occur.
The amount of gravel constantly Increases.

"The calcareous clays which overlie these on the Brazos undergo similar
changes. They become more sandy, gradually lose their lime in balls and
pockets, until at Colmesneil they retain only thin, platelike concretions. The
ferruginous matter in the form of plates and concretions increases and the
beds assume a red color, interspersed with black land prairies. Heavy sands
are interbedded with the clays.

"The most marked difference between the Oakville beds of this region and
those of the Colorado seem to be the entire absence of the coarse-grained,
cross-bedded sandstones, such as occur at La Grange BlufC. The Grimes
County sandstones, in general, are finer of grain, harder, more calcareous,
contain fewer Cretaceous fossils, are nearly always thin-bedded and flaggy,
and seem to occupy a place of lesser importance as a whole than those of the
Colorado."

The strong unconformity between his Oakville and Payette (?) is
brought out in connection with the contacts observed on Eocky Creek
north of Anderson.

"The Eocene member consists of 30 feet of massive, grayish yellow, coarse-
grained sandstone, quartzitic throughout, but the silicification has not pro-
ceeded to the extent of rendering the entire stratum blue and vitreous. Opal-
ized wood is present.

"Upon the eroded flanks of this Eocene hill lie the Oakville beds. They are
here represented by a coarse, brown calcareous sand, stratified and semi-
indurated in places, containing numerous fragments derived from the under-
lying Eocene quartzite, together with flint and jasper pebbles. At the line of
contact the sand is much mixed with clay and lignitized wood.

"Throughout this region there are occasional Eocene outliers, at times sev-
eral miles from the main contact."

He also notes that the dips of the older sandstones are considerably
greater than that of the Oakville.

Kennedy, Garrett, and Dunible made several trips across these sands
between the Colorado and Nueces rivers for the express purpose of ascer-
taining whether or not beds intermediate in age between the Frio and
Oakville could be found. In every case where the contact was found the
Oakville rested either on the Frio or the Fayette, and no indications of
other beds were observed. Many localities were found where marine in-
vertebrate fossils were abundant and well preserved, but they were nearly
all in Yegua territory. The principal, if not only, find in the Fayette
was a reef of Ostrea aldbamiensis var. contracta Con. This locality was

RECENT EXAMINATIONS 459

east of the San Antonio Eiver, on j\Iarcelina Creek, some 5 miles north
of Palls City, and it marks the extreme eastern limit of this form, so far
as now known. The last exposure of clays which we could refer to the
Frio was found just east of the San Antonio Eiver, east of which the
Oakville overlap concealed it, so far as our sections show. No marine
forms were found in it.

In 1912 and 1913 Balier and Suman spent several months in the Ter-
tiary belt between the Brazos and Sabine rivers, the greater part of this
investigation being of the post-Yegua deposits, although the beds under-
lying the Yegua were given sufficient attention to determine their bound-
aries. Large collections of fossils were made, which have not yet had
critical study except in special cases. Their reports and notes are very
full and satisfactory, but, owing to the heavily timbered character of the
country and the scattered exposures, they were unable to fully clear up
the situation. The maps prepared by them show their interpretation of
the surficial extent of the Marine, Yegua, Jackson, Corrigan, and Fleming
from near the Sabine River to the Navasota. They differ somewhat from
the published map and report of Deussen, both in their classification of
the beds and their boundaries.

The following descriptions are based principally on a study of their
reports, maps, and collections and on personal conferences with them.
The work of Kennedy and the writer in the same area has also been used.

Descriptions of Formations of East Texas
lower claiborne

Yegua. — The lignitic clays and sands of the Yegua are exposed over
an extensive area between the Brazos and the Sabine.

The clays are laminated, thinly stratified, and massive in structure, and
chocolate, dark blue, brown, and gray in color. The cone-in-cone struc-
ture, noted on Atascosa Creek in the Nueces section, is also found in the
basal beds of this area. The sands and sandy clays, which are sometimes
micaceous, are brownish drab, buff, and gray. They range from lami-
nated to massive and are often cross-bedded. Laminated clays and sandy
clays, sometimes leaf-bearing, frequently occur as lenses, pockets, and
nodules in the sands, even when the latter are cross-bedded. Similar^,
lenses of sand are found in the laminated, jointed clays.

In the lower portion of the beds the clays seem to predominate. The
middle portion seems to carry the most ]i,gnitic matter, and the sands
prevail in the upper beds.

Botli clays and sands weather to light colors, mostly yellow or dirty

460 E. T. DUMBLE PROBLEM OF TEXAS TERTIARY SANDS

white, and some of the sandy clays show typical badland weathering.
The topographic expression is generally flat.

In the upper beds, referred to this formation by Baker and Suman,
some of the sands have a porcelaneous cement, others limonitic, and still
others contain streaks and balls of white clay having the appearance of
porcelain.

Lignitic material is abundant, disseminated through the beds in frag-
mentary form, as carbonaceous coatings, and in lenticular beds ; but few,
if any, deposits of workable lignite are known to occur in the Yegua east
of the line of the International & Great N'orthern Eailway.

Gypsum is very abundant. In the lower portion of the beds, where it
predominates, it occurs as large masses of selenite of irregular form.
Elsewhere it occurs as crystals of selenite, sometimes of large size, or as
fragments intermingled with the sands and clays. In some localities
these gyjisum fragments constitute a considerable percentage of the sand
bed. Saliferous strata also occur.

The cannon-ball concretions of the Eio Grande are found here in
abundance. While some of these are of spherical shape, as on that stream,
many of the clay-ironstone concretions are in the form of flattened masses,
some of them 2 to 3 feet in diameter. They are usually altered to
limonite, and these limonite concretions and impregnations are character-
istic of the beds. Occasionally the limonitic concretions have streaks of
calc-spar through them, but true calcareous concretions are ajiparently
absent. Silicified wood is plentiful as logs of large size and as fragments
scattered through the formation from bottom to top, but none of it is
opalized.

Marine invertebrate fossils occur occasionally as poorly preserved casts
in connection with pockets or concretions of greensand marls. Fossil
plants are found abundantly at many places.

The Yegua belt has an average width of .12 miles. Its greatest width,
22 miles, is found along the ISTeches Eiver, while on the Sabine it narrows
to 3 miles. In dip it varies from 40 feet to tlie mile to more than 100
and has a thickness of 400 to 800 feet.

Fayette. — The fossils on which the correlation of Kennedy's Wellborn
beds with the Fayette was based were collected from the lowest beds of
the sands. The more recent work of Deussen and Yaughan seems to
indicate that this may prove to be Jackson. In this event, we know of
uo Faj^ette east of the Brazos, unless it l)c such remnantal areas of sand
and clay as those between Blix and Huntington.

On the west side of Jacks Bayou, just east of Blix, in Angelina County,
there is a ridge of evenly bedded medium or fine-grained sandstone of

BULL. GEOL. SOC. AM.

VOL. 26, 1914, PL. 25

Figure 1. — Yegua ox Trimty River above We.st.moeelaxd Bluff
Photograph by C. r.. I'.ake.-

KiouiJK 2. — Voi-Canic A.sii i.\ Jacksox. Wiini: Uock ('i!eek, 'I'uinitv fouxTY

I'h'jtograiili li.v < '. 1,. I'.nkiT

YEGUA FORMATION AND VOLCANIC ASH

DESCRIPTIONS OF FORMATIONS 461

light gray color. The ridge is 20 feet in height, and a well 50 feet deep
found only the same sand. A smaller ridge of similar sands trends east-
ward, crossing the line of the Houston, East & West Texas Railway north
of Burke, where there is another hill similar to that at Jacks Bayou and
composed of similar fine-grained massive or medium-bedded sands. In
this area a silicified tree trunk was found. It was not opalized. South
of this a third area of these light gray sands stretches almost to the line
of the Jackson contact.

The town of Homer is underlain by a light bluish gray, cross-bedded
sandstone. North of the town this changes to even-bedded, medium-
grained sandstone, which is quarried for local use. It is overlain to the
south by light cream-colored clay, thin-bedded to massive, and showing
cross-bedding in places. Finally, there is a small hill of similar fine-
grained sand, hardened to quartzite, just south of Huntingdon.

Similar remnantal bodies of fine-grained sandstones are found as de-
tached hills or ridges overlying the Yegua in interstream areas and north
of all recognized Jackson as far west as the northwest corner of Grimes
County. An outcrop of very similar sand was also found overlying the
Cooks Mountain beds of the Marine as far north as Alto, in Cherokee
County.

These sands differ from any of those found in the Yegua, Jackson, or
Catahoula, both in material and structure. From their location it would
seem improbable that they can be outliers of the Catahoula, and they are
so different from the underlying Yegua that they can hardly belong
with it.

The evidence seems clear that their stratigraphic position is between
the Yegua and the Jackson, and if this be true they probably represent
some part of the Fayette-Frio time of the Eio Grande section.

Frio. — No evidence was foimd between the Brazos and Sabine of the
existence between the Yegua and Jackson of any beds representing the
Frio. If they were deposited in Claiborne time succeeding the Fayette,
they were completely eroded.

UPPER CLAIBORNE

Nowhere in the Texas coastal area have any beds yet been found the
fossils of which would suggest a reference to the Upper Claiborne, and it
seems probable that this period was one of elevation and erosion in this
region.

JACKSON

Eobinsons Ferry is on the Sabine liiver, about H miles south of Colum-
bus, Louisiana. A quarter of a mile below the ferry Deussen found an

462 E. T. DUMBLE PROBLEM OF TEXAS TERTIARY SANDS

outcrop of shales carrying such Yegua forms as Pleurotoma terebrifor-
mis, Marginella semen, and Corhula oniscus}'^ Half a mile below this
Veatch found a blue fossiliferous clay, which yielded ''a rather extensive
Jackson fauna, including Umlrella planulata and many large Capulus
americanus." ^~ Outcrops of overh'ing beds seen do^\'n the river seem to
be principally of clays and sandy clays. North of Anthonys Ferry these
clays are succeeded by the Grand Gulf or Catahoula sandstone, giving
the Jackson outcrop a width of between 3 and 4 miles on the Sabine.

According to Baker and Suman, the northern limit of the Jackson, on
the line of the Santa Fe, is not clear, but is probably near Rush or be-
tween Rush and Bronson. The Jackson-Catalioula contact is Just south
of Brookeland. No fossils were found in this section.

From the valley of Ayish Bayou Avestward the base of the Jackson was
more easily determined by reason of the occurrence of a series of dark
clays with greensand and calcareous concretions carrying fossils. The
line thus given crosses the St. liouis & Southwestern Railway north of
White City, the Angelina River 2 miles north of Caddell, follows the
line of the St. Louis & Southwestern Railway from Monterey to Donovan,
and crosses the Texas & New Orleans Railway just south of Prestridge
and the Houston, East & West Texas Railway in the vicinity of Diboll.
In the area east of the railway the general section of the Jackson from a
number of sections and traverses of Baker and Suman shows :

At the base are greenish clays and sandy clays with some sand and
ffreensand, which are iron-stained. These weather dark brown and carrv
calcareous concretions. The concretions contain more or less sand and
greensand, are geodic in places, and they carry Jackson invertebrate
fossils and remains of plants. These are overlain by grayish browai, sandy
clays with seams of sulphur, which are followed by buff, sandy clays
with plant fragments, and gray drab clays with gypsum and sulphur.
Excellent exposures of these beds are found around the to^wTi of Caddell,
San Augustine County, and that name is proposed for this stage.

Overlying these there is a series of lignitic or carbonaceous chocolate
clays and sands, with which are interbedded light-brown sandstones with
a porcelaneous cement, and coarse-grained gray sandstones which are
sometimes quartzitic. In the vicinity of the Angelina River and else-
where thin beds of lignite are found.

The upper beds are of light greenish sands and carbonaceous sandy
clays stained with limonite and weathering into badland forms, capped
by dark-brown, sandy carbonaceous shales with plant fragments, selenite,

3" U. S. Geological Survey Water-supply Paper No. .335, plate iv.
*' Geol. Surv. Louisiana, 1902, pp. 131-132.

DESCRIPTIONS OF FORMATIONS

463

and sulphur seams. For this upper stage the name Manning is proposed
from the station of that name on tlie St. TjOuis & Santa Fe Eailway,
where they are well exposed.

In this area the Jackson belt has a width of 8 to 14 miles and a prob-
able thickness of 400 to 500 feet. East of Corrigan a well beginning in
the base of the Catahoula passed through the Jackson and Yegua beds
and reached the fossiliferous Marine beds at 1,300 feet. This would give
the Jackson a thickness of about 600 feet in this locality. The beds are
not only thicker tlian on the Sabine, but they become more anrl more
sandy toward the west.

West of the Houston, East & West Texas Railway we find the Caddell
clays with fossiliferous calcareous concretions on Tar Kiln Creek some
5 miles southwest of Diboll, at which place well preserved fossils were
collected, and it outcrops again about 12 miles northeast of Groveton, on
the Groveton, Lufkin & Northern Eailway. This was as far west as we
could trace it.

Fossils are of more frequent occurrence in this terrane than in any
other in east Texas except the Marine beds. Those near the base occur
in connection with the calcareous concretions. Sometimes the shells are
present in the concretions or weathered out from them, but more often
the shell material has been leached out, leaving only the imprint.

From the Tar Kiln Creek, 4 miles southwest of Dil)oll, the following
forms were identified :

Ostren frag, like contracta
Area sp. V

Yencricm'dia planicosta Lam.
Venericardia rotunda Lea.
I'cctKnciilns idoneus Con.
PcctuHCuIus sp. ?
Crassatclla texana Heilp. ?
CrassatclJa flexura
Corhula alaharnicnsis Loa.
Corbiila oniscus ?
Cytherea tornadonis Har. ?
Tcllina mooreana

Tellina sp.
Turricula sp.
Bulinella Icellogii Gabb
Turritella nasuta Gabb
Turritclla hotistonia Har.
Solarinm alveatum Con.
Solarium huppcrtsi Har.
Vohitilithes pctrosus
Cax-'^hlaria sp.
Calijptrca sp.
Dcntaliuni dumblci Har.
FlabeUum wailesii Con.

In tbe yelluw, sandy euncretions are many large Pinna, Pholodomya,
Echinoderms, .sni;ill l/aminea grandis, etcetera.

In connection witb tbcso bods north of Manning a fragment of a verte-
bra was found, wbicli is probably Zeuglodon.

At a somewbat biglier horizon tbe brown sands carry a number of
fossils in tbe form of casts. This appears to be the special horizon of
Haminea grandis.

46-1 E. T. DUMBLE PROBLEM OF TEXAS TERTIARY SANDS

111 tlio j\Iaiiiiiiig beds many lamellibranehs are found in the limonitic
shales, and in tlie overlying" light-gray sands there are pockets of fossils
wliicli are mostly casts, but occasionally liave the shells preserved. Simi-
lar occurrences were found in the cartioiiaceous shales and sands at the
top of the section.

No specimens of Levifusus hrannerl were found, but in the upper
carbonaceous sands of the Manning stage there are imprints and casts of
a large gasteropod that may possibly be referred to that species.

A marked increase in the sandiness of the Jackson is shown in the
Grove ton section.

.The sandy clay with limestone concretions, found 12 miles north of
Groveton, grades upward through carbonaceous shaly clays into a succes-
sion of gray and brown sands and lignitic sands carrying silicified wood,
some limestone concretions, clay balls, fragments of volcanic tuff, and
many plant impressions. Wells drilled at Groveton to depths of 400 to
600 feet show principally sands or sandy strata, with a few clay beds and
streaks of lignitic material. South of GroNcton carbonaceous sands are
found with imprints of invertebrates similar to those at the top of sec-
tion north of Corrigan.

Going northward the Caddell clay of this section is underlain by sandy
carbonaceous shales and sands, with silicified logs, massive, rather fine-
grained, sandstones and lignitic clays and sands seemingly of Jackson
facies. These extend to the vicinity of Apple Springs, beyond which the
Yegua badland sandv clays and gypsiferous clays with clay ironstone
concretions make their appearance. It would appear, therefore, that this
section gives us a member of the Jackson lower than any seen east of the
ISTeches or of a series of beds intermediate in age between the Yegua and
Jackson, most proliably the former.

West of Groveton the change is decided. Xo further traces of the
Caddell sandy clay with limestone concretions are found, but the lignitic
sands and clays underlying it seem to be immediately overlain l)y the
carbonaceous sands of the Manning beds, as shown in section north of
Corrigan. Volcanic ash comes in as definite beds and is well shown in
the section along the International & Great Northern Railway.

Between Calhoun's ferry, near the Houston-Trinity County line and
the bend north of Riverside, the Trinity River gives many good sections
of the Jackson. At the base are lignitic clays carrying plant remains
and sands with lignites. These are overlain by light-yellow, gray, and
brown sands, with sulphur, and by carbonaceous shales, sulphur-stained,
followed by other lignitic clays, sands, and lignites. There are beds, of
volcanic ash as much as 10 feet in thickness in the upper portion, and

BULL. GEOL. SOC. AM.

VOL. 26, 1914, PL. 26

"l>;i l;i: 1. -('ukiim.an S.wds \f.\i: I! i \ ijisini:
riKjiogiapli l).v (' L. I'akiT

FlGUHK '2. — l-'i.,K.Mi.\(; f'l.w.s. S.Miiii.^ I'kuh^. .Xkciik.s HiVl'.ll
I'hotojjraph bj' J. U. Snniaii

COBBIOAN SANDS AND FLEMING CLAYS

DESCRIPTIONS OF FORMATIONS 465

these carry plant fragments. The volcanic ash beds give a good working
horizon, as they are fairly continuous west of Groveton.

Sections in Walker and Grimes counties are very similar to that on the
Trinity. At one locality, near the line between these two coimties, a bed
of laminated chocolate clays was found, in which there were balls and
masses of Grahamite 8 to 10 inches in diameter.

Fossils were found in colonies in sandstones near the base of the Jack-
son series at a nimiber of localities west of the International & Great
Northern Eailway, and the upper carbonaceous clays of the Manning
stage also furnished a few fossil-bearing localities similar to those further
east. At one localit}^, 2^^ miles west of Bedias, Suman reports the sand-
stone packed with fossil casts apparently identical with those from 2
miles north of Corrigan. The fossils collected from these have not yet
been studied.

Unfortunately, the work was suspended before the exact connection of
these beds and the Wellborn of Kennedy was determined. The proba-
bility, however, is that they are the same, and that Vaughan's reference
of the Wellborn to the Jackson is correct. In this case the name Well-
born, instead of being a synonym for Fayette, would characterize the
basal beds of Jackson age in Texas.

The Jackson is distinguished by the fact that in it the clay ironstone
and limonitic concretions of the underlying Yegua are replaced by cal-
careous concretions and by a greater proportion of sands and sandstones.
Some of the Jackson sands are very hard, even quartzitic, but are always
light gray in color and are fossiliferous in places. Volcanic ash beds are
also characteristic. The top of the Jackson is placed where the chocolate
laminated clays and carbonaceous sands give place to coarse "rice" sands
or sandstones and yellowish green, structureless clays and claystones.

CORRIGAI}

The name Catahoula has been proposed by Veatch for the sands over-
lying the Jackson and underlying the Fleming, but expressly limited its
use to such as were of true Grand Gulf age. Deussen used the name in
a mucli wider sense to include a large part of the Jackson as well. It
is here proposed to use Kennedjr's older term Corrigan sands for the
group of deposits lying between the known Jackson and the Fleming,
which, while forming the only mapable unit, prol)ably includes beds of
later age than the Catahoula of Veatch, which name should be retained
for that portion of the Corrigan to which it strictly applies.
XXXVI— Boll. Geol. Soc. Am., Vol. 26, 1914

466 E. T. DUMBLE PROBLEM OF TEXAS TERTIARY SANDS

The Corrigan comprises coarse "rice" ^^ sands and sandstones at the
base, overlain by finer sands and by yellowish green clay and claystones
with plant remains. The clays and claystones carry pyritic nodules and
streaks of lignite and weather yellow to cream color. The sands are
coarse to fine-grained and may be friable, cemented Avith opaline or por-
celaneoiis matter, or hardened to a dense gray-ljlue quartzite. There are
local unconformities between the sands and clays and the sands often
carry clay balls and are occasionally cross-bedded. Volcanic ash is rare
in them. They are noted for the abundance of fossil palms, and the fossil
wood which occurs in them is often opalized.

On the Santa Fe, in Jasper County, the contact of the Corrigan and
Jackson is found just south of Brookeland, and it passes under the Flem-
ing about 5 miles north of the Jasper. Many excellent exposures are
found along the Angelina and the ISTeches rivers west of this. On the
Texas & New Orleans Eailroad the outcrop, as determined by Baker and
Suman, has a width of 5 miles, with Rockland as its center. In the Cor-
rigan section, which begins one mile north of Corrigan and extends south-
ward to Moscow, we find these materials tyi^ically displayed, and in con-
nection with them local conglomerates occur. A\itli i)ebbles of jasper, flint,
and quartz up to mi iiidi in diameter. Palm leaves are abundant also.

In the exposures of the Trinity Eiver region, while the basal beds are
the same as those to the eastward, there appears to be at the top a tran-
sitional zone, in which sands of the Corrigan are interbedded with cal-
careous clays similar to those of the overlying Fleming. On this account
the limit is not as well defined as further east, and the upper line is
drawn where the sands with porcelaneous cement cease and the clays
weather entirely dark brown or black, instead of showing the character-
istic yellow weathering of the Corrigan clays.

These upper beds maintain their character and thickness as far west as
the Navasota Eiver. While they appear to be later than the Catahoula
]H'oper, they are definitely connected Avith it by the character of the sands
and clays of which they are composed.

For this portion of the Corrigan the name Onalaska is proposed, from
the name of a town in Polk Coimty which is located on them. Excellent
exposures may be found on Kickapoo Creek east of the town and on
Harmon Creek northeast of Huntsville.

On the Trinity & Brazos Valley Railway, in Grimes County, the Jack-
son-Corrigan contact was found about 21/2 miles south of Singleton and
the Corrigan-Fleming contact just north of Eichards.

Although two or three fragments of bone were found in the sands, no

' So caHed because of the resemblance of the grains to those of rice.

BULL. GEOL. SOC. AM.

VOL.26, 1914, PL. 27

CONTACT OF JACKSON AND CORRIGAN FORMATIONS
View on Trinity River near Trinity. Photograph by C. L. Baker

DESCRIPTIONS OF FORMATIONS 467

determinable fossils except plant remains have been secured from these
beds, and while good collections were made we have as yet no definite
information as to the exact age indicated by them.

Stratigraphically, this group is post-Jackson. Lithologically, the base
corresponds closely with the typical Grand Gulf, while the top is very
similar to the Oakville beds of the Nueces section, and up to the present,
in the absence of determinable fossils other than plants and on account of
the apparent stratigraphic connections, it has seemed to the writer that
the group represented a remnantal area of Catahoula overlain or sur-
rounded by the Oakville. Baker and Suman did not find any basis for
such a division of these beds, but regarded the observed unconformities
as local only, and, in view of the age of the fossils found in beds overly-
ing the Corrigan, it may be that this opinion is no longer tenable as a
whole. It now seems probable that the Corrigan represents some portion
or all of the Oligocene above the Vicksburg (which is wanting in this
area), and that while the base may be Grand Gulf the upper portion is
probably later.

FLEMING

South of the Corrigan sands and overlying them there occurs a broad
belt of clays and sands, with quantities of calcareous concretions, which
were called by Kennedy the Fleming clays. They occupy a belt from 15
to 25 miles in width and are followed by the deposits referred to the
Lafayette or Eeynosa. Since no clear basis for the division of these beds
was found, the name Fleming as used here includes all sediments between
the Corrigan sands and the Lafayette between the Sabine and Navasota
rivers, and these were mapped as a unit, although they probably comprise
deposits of both Mioceiie and Pliocene age.

Burke^■ille is near the base of the Fleming clays as exposed in the
region near the Sabine liiver. Baker describes the deposits here as fol-
lows :

"In color the Fleming is most generally a light shade of grayish or yellowish
green, often weatlieriug brown on the surface. The surface, when dry, is
cracked like ordinary plastic clay. The material is fine clay and clayey sand,
with small whitisli limestone concretions. However, there are, at Burkeville,
larger grayish brown, very fine-grained limestone concretions with dendritic
markings of manganoso dioxide, concretions of fine- to medium-grained sand-
stones, of large size and rough, irregular outline; and the fossiliferous breccia
or beach limestone conglomerate known oidy from one-half mile east of Burke-
ville and soutli of Little Cow Creek, where fragmentary bones of land mam-
mals and l)raclvish water mollusks were found. In many places the small
white concretions are arranged in thin beds parallel to the imperfect lines of
stratification. The fine sands are also locally finely laminated and cross-
bedded."

468 E. T. DUMBLE PROBLEM OF TEXAS TERTIARY SANDS

Kennedy's original section^" shows at base calcareous clays overlain by
other clays and by gray stratified sands, with fossil palm-wood in quanti-
ties and with pebbles of quartz, jasper, flint, etcetera. Higher beds found
on the Texas & N'cav Orleans Railway south of Eockland are sandy clays
of various colors, with interbedded sands, and the upper beds of calcare-
ous clays were found near Woodville, south of which the Fleming is
overlain by the Lafayette.

The Trinity Eiver section similarly shows at the base green-brown
clays with calcareous nodules. At Eed Bluff there are greenish gray
clays with calcareous nodules and cross-bedded sands in which bone
fragments are found. The exposure of these beds has here a maximum
thickness of 15 feet. In the middle of the exposure there is a layer of
oolitic shoreline limestone conglomerate a foot in thickness containing a
few jasper and quartz pebl)les of small size and an occasional bone frag-
ment.

Similar beds are found a short distance below at Johnson's bluff, where
they also include fresh-water mollusks. These deposits extend along the
river to a point south of Drews Landing, near Smithfield. Here an out-
crop of Fleming, 10 feet in thickness, shows friable fine-grained gray
sandstone in lenticles at the base, with 5 feet of greenish gray, russet-
brown, mottled clay witli small, white calcareous nodules overlying it.
Fragments of bone were found in this. The Fleming is here overlain by
the Port Hudson, with the usual layer of Lafayette-derived pebbles at
the base.

A mile below Drews Landing, in a section of o feet of light-gray Flem-
ing clay with calcareous nodules, a portion of the remains of a mastodon
was found.

Cold Springs, west of the river, is in the midst of an important out- .
crop of the Fleming. In this region the Fleming brown and gray clay
has a considerable portion of brown, buff, and white sand. Locally there
are large boulders of grayish browoi, soft sandstone, some of which are 10
to 12 feet in length. There is also a fine-grained, hard, brown claystone
and numerous calcareous nodules. Crystals of selenite are found locally.
Pure white sand, with only a minor amount of clay, is also found. Fos-
sils of mammals were found in the region extending from 2 miles north
to 2 miles west of Cold Springs. The bones, with the exception of a
mastodon's skull (TrilopJiodon), are fragmentary and are scattered
through the clays. Planorhis was also found at this locality.

Baker describes the Fleming of the ISTavasota region as follows :

S9 Third Anu. Rept. Geol. Surv. Texas, pp. 117-121.

DESCRIPTIONS OF FORMATIONS 469

"The lowermost Fleming is exposed in a cut on the International & Great
Northern Railway 3 miles north of Anderson, where there is 0 feet of green
sandy clay very poorly laminated, carrying calcareous cemented nodules of
sandstones. From Anderson to Navasota the railroad passes over Fleming,
which is here composed mainly of clays, but locally of gray and brown sands
and sandstones. Seven miles northeast of Navasota and half a mile east of
Becker flat-topped mesas capped by sandstones and very arenaceous limestone
begin and continue nearly all the way to Navasota. These are entirely south
and east of the track and rise to 100 feet above the track level. The Fleming
in this vicinity consists of the following materials :

"1. Sands of all textures from the finest up to coarse grit or fine C(jn-
glomerate.

"2- Brown and dirty green clays with calcareous nodules.

"3. Very arenaceous, thin, irregular-bedded, and concretionary limestone.

"4. Clay ball conglomerate in a coarse sand matrix.

"All of these materials are either channel or littoral deposits. Mammalian
bones are found in a layer of coarse grit or fine conglomerate. They are
fragmentary, sometimes water-worn, and are associated with rolled Cretaceous
fossils. Petrified wood, differing from that of the older formations in being
less consolidated, lighter in weight, and duller in luster, was found with the
bones and shells. Fresh-water shells (unios) are foimd in abundance in the
clays between 3 and 4 miles north of Navasota in shallow guUeys just east
of the right of way. The bones are found in the deeper gulleys to the east
of the second mile-post."

South of Navasota the Fleming continues to 11/^ miles south of Crooks,
where the Lafayette begins, the uppermost Fleming being made up of
dirty green clays with white calcareous nodules. AVest of this it con-
tinues southward and is exposed at the Houston & Texas Central Rail-
road crossing of Clear Creek, just east of Hempstead, where it has the
appearance of the Lagarto of the Nueces section and, like it, carries
manganese as fragments of wad.

The invertebrate fossils collected at the Burkeville locality were sub-
mitted to J)r. \y. H. Dall, who had already had other collections from
the same locality, the result of the study of which is given by Matson.*"
Ten species are listed from Burkeville, and Matson states that the char-
acter of the fauna led Doctor Dall to refer it to the Pliocene. This is the
only locality at which this fauna has been found on the surface. In a
well at Terry, 6G miles south of Burkeville, however, at a depth of 3,000
feet, the same forms were found in abundance, and in a second well, a
mile or more south dF the first, they continued to the bottom of the drill-
hole, wliicli was a little iiHU'c! than 1,000 t'oet below the surface. Doctor
Dall dctci-niiiicil tlu' fdllnw iu^j- forms from these wells:

^^U. S. Geological Siiivi-.v Waler-siipply Taper No. .'WO, pp. 72-73.

470 E. T. DUMBLE PROBLEM OF TEXAS TERTIARY SANDS

Ostrea virginica Gm. (fragments) Fotamides suavis Dall

Rangia cuneata var. solida Dall Potamidcs sp. (fragments)

Unio sp. (fragments) Pyrgulopsis ? satiUa Dall

Potamides matsoni Dall Neritina sparsilineata Dall

In connection with the invertebrate fossils at the Burkeville locality,
Baker collected some mammalian fossils which were studied by Doctor
Matthew. He reports as determinable:

Tibia of a young rhinoceros, with the proportions of Teleoceras.

Upper molar of a horse, either Protohippus or a long-crowned Mery-
chippus.

He states that both these specimens indicate late Miocene or possibly
early Pliocene age, the horse tooth being pretty certain evidence.

It is therefore evident that in the vicinity of Burkeville the base of the
Fleming is not earlier than late Miocene nor younger than early Pliocene.

In the Neches River section, at the base of the Fleming, a bone was
found by Baker which was determined by Doctor Matthew as "part of
the upper end of cannon-bone of a Camelid, compared Procamelus. This
might be Middle Miocene or Pliocene, so far as comparison of known
species of Camelidae goes."

Collections of vertebrates were secured from the Cold Springs horizon,
which is above the center of the series of deposits in the Trinity drainage
here referred to the Fleming, and from the Navasota horizon, which is
near the base of the section on the Brazos River. These were sent to Dr.
W. D. Matthew, who reports as follows:

344. Two miles west of Cold Springs.

"Trilophodon sp., parts of lower jaws and separate molars, mostly well
preserved.

The best specimen shows a large part of the lower jaw with '>n^_^,
and the molars of the opposite side. Part of the symphysis is pre-
served, and apparently a little of the alveolus for the lower tusk.
Symphysis is moderately long, slender ; not decurved. The species
is a very small and primitive one in most respects, but the retarding
of the posterior teeth so that vis does not come into use until m^ is
worn out and dropped is suggestive of Upper Miocene species, such
as T. euhypodon. The small size and primitive construction of the
teeth are more suggestive of Middle Miocene.

Indicated age, probably Middle Miocene.
"Peccary, gen. indet., jaw fragment, 1113.

This might be anything from Percliwrus (Oligocene) to Prosthen-
nops (Upper Miocene). It is small and primitive, so far as the tooth
goes, but this is not conclusive, as the progressive characters of this

DESCRIPTIONS OF FOEMATIONS 471

phylum are in the front teeth. I can not identify it with certainty
as belonging to any known genus or species.
Indicated age, Oligocene to Upper Miocene.

"Mcrychippus sp., upper and lower teeth.

A rather small and moderately progressive species; it might be
Upper or late Middle Miocene-
''f Alticamclus, distal ends tibia and metapodial.

Indicated age, Middle Miocene to Lower I'liocene.
"Crocodile and Tortoise fragments.

345. Pointblank road, north of Cold Springs.

"Cervid, cf. Dromomcrijx, horn fragment, calcaneum.
"Camelid, gen. indet, jaw fragments, proximal phalanx.
"Rhinoceros, cf. Aphelops, several fragments limb bones, calcaneum.
"Large Rhinoceros, cf. Teleoceras or large Aphelops, fragments of limb

bones.
"Proboscidean, cf. TrilopJiodon, unciform.

Indicated age of the above specimens, Middle Miocene to Lower
Pliocene.

345. One and one-fourth miles north of Cold Springs-

"Hystricops sp., upper jaw with m*; lower molar.

This is more primitive than the one known species of this genus,
which is Upper Miocene and Pliocene. It is intermediate between it
and the supposed ancestral type, the Steneofiber group of the Upper
Oligocene and Lower Miocene.

Indicated age, probably Middle Miocene.
'' Blast omcrijx sp., last lower molar.

This is apparently distinct from any known species, decidedly more
progressive than those of the Lower Miocene, less so than the Upper
Miocene species B. xvellsi, more perhaps than the Middle Miocene
species B. gcmmifer.

Indicated age, late Middle Miocene or Upper Miocene.
"? Orcodont, gen. indet., upper canine and premolar.

Indicated age, Miocene or Lower Pliocene.
"Carnivore, indet., scapholunar and head of metatarsal.
"Proboscidean, cf- TrUophodon, fragments of teeth.

Indicated age. Middle Miocene to Pliocene.
"Trionycliid fragments.
"Carpike scales.
"? Snake vertebra.

''Mcrychippus sp., cf. srvrisn.s. upiter ami lower teeth and fragmentai'y
foot bones; part of right lower jaw. Pt-m^.

This is a Middle Miocene stage, although small and primitive
Merychippi do survive nito the Upper Miocene and Lower Pliocene.
No tiMcc of iiiiy of I he distinctively l'i)p(>r Miocene horses among
tliesc fi-agmcnts.

Indicated age, Middle Mio(;ene.

472 E. T. D.UMBLE PROBLEM OF TEXAS TERTIARY SANDS

351. Two miles north of Cold Springs.

"Cervid {? Dromomeryx) radius.
"Trionycliid plate.

Indicated age, DromomcTyx is Middle Miocene to Lower Pliocene,
but this evidence is very slight.

352. Red Blufe, Trinity River.

''Protohippine horse, lower tooth.

Indicated age, Middle ^Miocene to Pliocene ; nothing more definite.

.'549. Two and one-fourth miles north of Navasota.

"Merychippus, small species, cf. M. sever suh, but probably not identical,
upper molar and fragments of foot bones.

Indicated age. Middle Miocene, ]»ut Upper Miocene or Lower Plio-
cene is not excluded.
"Rhinoceros, cf. Aphelops, fragments of teeth, head of radius.

Indicated age, Miocene.-
"Camelid, cf. Protolahis or Procamelus, fragment lower molar, astragalus,
navicular, unciform, fragments of foot bones, ? symphysis of jaw.
Indicated age, Miocene or Pliocene.
"Testudo, large species, carapace fragments.
••Crocodilian, fragments of skull.

"(ieneral conclusions : Fauna of Navasota and Cold Springs localities appears
to be the same. It is certainly not earlier than Middle Miocene of Osborn's
correlation, nor younger than Lower Pliocene. Absence of all character-
istically Upper Miocene or Lower Pliocene mammals points to Middle Miocene
as the proper correlation. But there are two points which should be consid-
ered as making for a possible later date than the comparison indicates: (1)
Our land faunas are mo.stly derived from the north and northwest, and older
types may have lingered longer along the Atlantic and Gulf coasts than in the
northwest, thus making the fauna seem older than it is; (2) Knowlton re-
gards the Mascall on plant evidence as Upper Miocene. This, if accepted,
would set our whole scale of continental Neocene horizons a little higher than
does ()sborn"s correlation. If you give much weight to these considerations,
they might serve to set the correlation up to Upper Miocene. The fauna is
quite decidedly older than the Blanco.

'•A parallel case occurs in Mexico, where Freudenberg has described a
mammal fauna of Pleistocene age, but largely of Pliocene type, as compared
with our Plains succession."

So far as reported, no vertebrate fossils have been found in the Fleming
which are referable to the BJanco or other later Pliocene horizon.

The horij^on from which the Navasota fossils were taken and that of
the Burkeville fossils are similarly related to the Corrigan-Fleming con-
tact and are near the base of the Fleming l)eds. The Cold Springs hori-
zon is mnch higher and is in the upper half of the Fleming. It would,

DESCRIPTIONS OF FORMATIONS 478

therefore, appear that the base and even the middle of the Fleming west
of the Neches is older than the base of the Fleming east of that stream.

West of the Colorado the Neocene beds are composed principally of
sands with smaller proportions of clay, while east of the Brazos these
conditions are reversed.

The fossils fomid in the Oakville of the Xueces sections, as determined
by Cope — Protohippus medius, P. perditus, P. placidus, and Aplielops
meridianus — indicate a higher horizon than that of Navasota or Cold
Springs. Not enough material is at hand to decide its exact relationship
to the Burkeville. Based on comparison of vertebrate remains, they may
be of similar age; but if the invertebrates are to govern, the Burkeville is
more nearly the age of the Lapara, in A\'hich case Hager's reference of
the sands at Burrs Ferry, on the Sabine, to the Oakville may be true.

Since the fossils obtained from the Fleming beds show that they cover
Middle and Upper ]\Iiocene and Lower Pliocene time, they must include
the eastern time-representatives of the Oakville and Lapara beds, al-
though lithologically the Fleming is dissimilar to the Oakville and La-
para. The Fleming resembles the Lagarto and, while no Middle Pliocene
fossils have been found in it, it is possible that the Lagarto may also be
represented in the upper portion of these beds as exposed around Wood-
ville and at Hempstead. This would make the Fleming the representa-
tive, east of the Brazos River, of the entire Neocene series west of that
stream below the Lafayette.

The apparent beds of passage between the upper part of the Corrigan
and lower beds of the Fleming may signify comparatively continuous
sedimentation in the vicinity of the Trinity River from the Grand Gulf
to the Lafayette, while to the east and west of that locality land condi-
tions persisted longer, the older beds were more slowly submerged, and
we have the Upper Miocene or Pliocene at the base of the Neocene Ijeds
at the eastern extremity and Loup Fork at the western.

The entire sedimentation represents coiulitioiis in the west comparable
to those of the Staked Plains area and a comparatively arid climate, while
on the east they represent moistcr conditions, favorable to the formation
of marshes at or ni'nr tlic nioutlis of outflowing rivers.

Summary

The outcrops on the Sal)ine sliow oidy one sand — the Corrigan. Whetber
the Corrigan at tbi.s })oint embraces anything more than the Catalioula is
not fully known; but the Oakville sands may be represented, as indicated

474 E. T. DUMBLE PROBLEM OF TEXAS TERTIARY SANDS

by Hager, between the Catahoula and the overlying Burkeville stage of
the Fleming.

In the area between the Sabine and Trinity the Fayette, if it occurs at
all, is represented by remnantal patches.

In the Trinity Eiver section the Fayette and Frio appear to be want-
ing ; but in the Jackson the clays which were predominant on the Sabine
have largely given place to sand, so that we have here the Jackson sands
overlain by the Corrigan, which, apparently, graduates into the Fleming
through a series of interbedded clays and sands. The Oakville is prob-
ably represented on the Trinity by some part of the Fleming clays.

On the Navasota the Jackson sands (Wellborn ?-Manning) are fol-
lowed by the Corrigan, and the basal portion of the succeeding Fleming
is composed largely of sands, so that we have three formations in which
sand is predominant succeeding one another. The presence of Fayette
in this section has not been proven, nor has the Oakville certainly been
differentiated from the Fleming.

In our earlier work it was considered that the occurrence of opalized
wood was characteristic of the Fayette only. East of the Brazos, where
the Fayette is lacking, it is found in the Corrigan beds only. If it be
representative of the Corrigan rather than of the Fayette, it would change
the reference of our beds near Nails Creek, in Lee Count}^, and near
Ledbetter, from Fayette to Corrigan.

On the Colorado the section as previously understood will require re-
vision. No determinable fossils other than plants have been found east
of AMiite Marl Bluff, and it will require more detailed work than has yet
been done to decide the exact correlation of the various beds occurring
here.

White Marl Bluff, just west of the Bastrop-Fayette line, carries a
fauna which is distinctly that of the Marine beds. The Yegua, beginning
at the county line and continuing to near AVest Point, shows the charac-
teristic dark clays, sands, and lignites of that substage, with their limonite
concretions. These beds are followed, in the two exposures noted by Pen-
rose as "Chalk bluffs," by the typical light-colored sands and clays of his
Fayette beds. Some of the hard, gray sandstones connected with these
are seen just south of West Point. A series of darker colored lignitic
sands and clays, which are exposed from the vicinity of Ptabbs Creek east-
ward to the base of Palm Bluff, some three miles from La Grange, may
represent the Jackson in this section. It includes the heavy lignite beds
at Mantons Bluff. Overlying these, in Palm Bluff, there is a series of
sands and clays and quartzites, with opalized wood and palmetto, which
we have heretofore included in the Fayette, but which is lithologically

SUMMARY 475

similar to the Catahoula of the eastern section. There is a strong uncon-
formity between the massive coarse sands of this stage and the overlying
thin-bedded sand and clays, which are also palmetto bearing and which
we have heretofore classed as belonging to the Oakville. These thin-
bedded sands and clays arc overlain unconformably a mile west of La
(orange l)y limy clays with calcareous concretions carrying fragments of
bone. Tlie section of Town BluJl', or Monument Bluff, one mile east of
La Grange, lias already been given.

On the Kio Grande the only sands recognized are the Fayette and Oak-
ville. The fossils of the former, to the southern line of Starr County,
ai-e certainly Lower Claiborne. The brown or buff sand between this
point and the base of the Frio clays apparently contains no fossils except
tlie large oyster, which Harris has determined as 0. alahamienses var.
contracia of Conrad, but which was earlier called Ostrea georgiajia. This
oyster is also common in smaller form in the beds as far up the river as
Carrizo, and the buff sands in which it occurs arc found interstratified
with the other fossiliferous sediments.

Of the few Frio fossils found ])y us there were none characteristic of
beds later than the Lower ('lail)oi'ne : hut tliis was also the case with what
is noM' regarded as the Jackson, and there is a possibility that when full
collections are made from the Frio it may also be classed as Jackson, in
which case we will probably have a band of Jackson entirely across the
State, showing principally clays on the Sabine and Eio Grande and sands
between.

Our knowledge of the Oakville sands on the Rio Grande is not such as
"will permit more definite statements regarding them than have already
been made.

476

E, T. DUMBLE PROBLEM OF TEXAS TERTIARY SANDS

Possible Equivalency

The following table summarizes the possible equivalency of the various
sections :

Rio Grande:

West Texas:

East Texas:

Sabine River

Pliocene:

Upper
Middle

Reynosa

Lagarto

Lafayette
' Woodville

Lafayette

Woodville

Lower

La para

Burkeville

Miocene :

Fleming : ■

Upper

Oakville

Oakville ?

IMiddle

Cold Springs

Lower

Wanting

A\' anting

Wanting

Oligocene :

Upper

Corrigan ?

0°-«-- { SatSSa

Catahoula

Lower

Wanting

Eocene :

Manning ?

IManning

Upper

Frio ?

AVellborn ?

Jackson : -

Caddell
. Wellborn

Caddell

Middle

U. Claiborne

Wanting

AVanting

L. Claiborne

Frio ?

Fayette

Fayette ?

Yegua

Marine

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Vol. 26, pp. 477-483 DECEMBER 4, 1915

A STILVTIGliAPHIC DISTUl^EANCE TTTHOUGH THE OHIO

VALLEY, EUNNING FEOM THE APPALACHIAN

PLATEAU IN PENNSYLVANIA, TO THE

OZAEK MOUNTAINS IN MISSOUPI.^

BY JAMIvS II. (JAUDNKi;

(Presented before the Sovichj JJccrmher J'.i. J '■>!-'/)

CONTENTS

Page

Relations and extent of the zone of (listurhjiiice 477

Nature of the structure in the disturlciiuo zone 479

Mapping of the line of weakness 470

Intrusive materials 480

Broad geologic features 481

Kelations axd Extknt of pi IK Zone of Disturbance

The ^\Titer in recent years has done considerable geologic work in
connection witli a study of tlie oil pools that lie along the extension of
the Camptori anticline and the Rongh Creek uplift, in Kentucky. The
result of these observations, added to the work previously done by others,
has served to show tliat there is a zone of disturbance in the Paleozoic
rocks Avhich completely crosses the State in an cast-west direction. To
the west it connects with the Shawneetowai fault and Bald Hill uplift,
which is slio\vn by F. A\'. DeWolf on the State geologic map of Illinois
as completely crossing southern Illinois into iMissouri. To the east it
connects with the Warfield-Chestnut Pidge '/.one of folding, which I. C.
White has, with a sliglit interruption, mapped across the State of West
Virginia into Pennsylvania, showing tlic position of ir on liis State geo-
logic map. From the south lino of P('iinsy]\inii;i. on northward to a point
west of Clearfield, this same fold is vouclicd for l)y P. P. Hice, State
Geologist of Pennsylvania.

The distance now known to be traversed by this structure is approxi-
mately oGO miles. From Pennsylvania southwanl it is one of several

' Manuscript received by the Secretary of tlio (!i'iil(iv;ical Sociol.v May 14, 1015.

(477)

478 J. H. GARDNER — STRATIGRAPHIC DISTURBANCE IN OHIO VALLEY

s
s

D
CJ

NATURE OF THE STRUCTURE 479

anticlines produced by Appalachian folding, but in the Big Sandy Valley
along the border line of West Virginia and Kentucky it swings westward
along the Ohio Valley, crossing near the crest of the Cincinnati arch and
continuing across Kentucky and Illinois to the Ozark uplift. Surely, it
shows some sort of structural relationship between Appalachian structure
and these other large uplifts to the west.

Kature of the Structure in the Disturbance Zone

The structure varies in its nature from point to point along this zone,
depending on whether or not faulting occurs in connection with the fold-
ing. In Pennsylvania, West Virginia, and for some distance into Ken-
tucky it has been mapped as a low anticline, accompanied locally by dis-
placements of slight magnitude. But through central Kentucky and
westward to and through Illinois faulting is the predominant feature,
though at places it is a fairly regular anticline. In Ohio County, Ken-
tucky, it consists of a fault zone with parallel anticlinal folding on the
south side. Where faulted, the upthrow side is the south side or south-
east side, depending on the direction of strike and showing a thrust from
the south or southeast. It bears out consistently the fact that the thrust
was away from the direction of the seashore, just as is true of all Appa-
lachian structure. Where folded without faulting, the steeper side of the
anticline is on the north or northwest, depending on the curve of the
strike line.

'J'ho writer regrets that he is not in a position to make a more complete
study of this most interesting subject. What is given here, along with
tlie accompanying map, is to serve as a basis for more detailed investiga-
1 ions by others. Facts as now known warrant a closer study of the rela-
tions of the Ozark Mountains and Cincinnati geanticline to Appalachian
folding. The writer does not have the data before him nor the time at
Ills conmiand to go into a detailed description of this long line of dis-
turbance that appears to tie the three regions together. He does not at-
tempt to say just what it means. OIThand it suggests that Appalachian
folding was accompanicil l)y strong folding at the same time on the Cin-
cinnati arcli and in lln' O/^ark Mountains, this line being a relief of the
stresses tliat were set up across the intermediate areas.

Mappixo of the Line of Weakness

Very little nee(] he \ouched for by the writer in connection with the
authenticity of the map presented here which shows the position of this
lin<' 1)1" weakness. Knowledge regarding it in Kentucky has not horoto-
XXXVII— Ben.. Geoi-. Soc. Am., Vol. 26. 1014

480 J. H. GARDNER STRATIGRAPHIC DISTURBANCE TN OHIO VALLEY

fore been assembled, though Orton, Munii, Miller, Campbell, and Glenn
have mapped respective portions of it. The Rough Creek uplift, mapped
by Orton ; the Campton anticline, mapped by Munn ; the Kentucky River
fault zone, mapped by Campbell, and its extension, mapped by IMiller, as
well as the Sebree structure of Glenn, are all but sections of it in Ken-
tucky. The writer's work on the Hartford Quadrangle and former studies
in the region of Dividing Ridge and eastward has brought to light the
missing links in this long chain which has been unconsciously lined up
by several well known geologists. From central Pennsylvania to eastern
Missouri is a long way for such a structure to continue and not have been
previously kno^\Ti in the geology of North America; but such appears to
be the case. At least the writer has seen no literature regarding it as a
unit nor has he heard it discussed.

On the accompanying map a solid line is drawn where the structure is
known to be evident, and at points where it has not been mapped or is not
known to the writer it is sho^ra l)y broken dashes. It Mill be seen at a
glance that the broken line constitutes a very small percentage of the line
of extension. At a point northeast of Charleston, AVest Virginia; at
another near Paintsville, Kentucky, and a third just north of Connells-
ville, Pennsylvania, the folding is either obscure or has not been mapped.
At a point near Lebanon, Kentucky, the writer has not seen the structure
nor has it been mapped; but its presence here in the form of a strong
fault is vouched for by F. J. Fohs, formerly a member of the Kentucky
Geological Survey. It is at once evident that the points where its pres-
ence is obscure are so small as to l^e negligible.

Intrusive Materials

In three known localities near the line of this disturbance there are
intrusions of peridotite ; all three of these districts are well known : one is
in Fayette and Greene counties, Pennsylvania, described by R. R. Hice in
the biennial report, 1910-1912, of the State Geological Survey of Pennsyl-
\ania; one is in Elliott County, Kentucky, discovered by A. 11. Crandall
and described by J. S. Diller in Bulletin Number 38 of the United States
Geological Survey; the third is the Kentucky-Illinois fluorspar district,
first described by Ulrich and Smith in Professional Paper Number 36 of
the United States Geological Survey.

These intrusions of periodotite are all remarkal)le in that they are in
isolated districts remote from all other intrusions of igneous rocks. The
fact that all three of these localities lie near a line of regional disturbance
throws a new light on their occurrence. That the pressure initiating this

INTRUSIVE MATERIALS 481

line of stratigraphic yieltling affected the rocks to remote depths is cer-
tainly strongly suggested by the presence of these igneous intrusions.

There are no known dikes that cut through the surface rocks on the
Cincinnati geanticline, either on the Kentucky or Tennessee arches, but
there are numerous lead and zinc bearing veins, composed of calcite,
barite, and fluorite, that do cut across the Ordovician rocks of these domes.
Similar veins in the Kentucky-Illinois fluorspar district are related to the
dikes of peridotite, where they cut walls of limestone and are accompanied
by faulting. The depths to which the mineral veins continue on the Cin-
cinnati geanticline are not kno^ai ; the Chinn vein of calcite and fluorite
on the Kentucky Eiver, in Mercer County, Kentucky, passes down into
the lowest rocks exposed in Kentucky, the same being the Camp Nelson
beds of the Ordovician system. These veins completely fill wide fissures
in limetone, and to what extent they have been eroded may never be
known; but, in view of the facts brought to light in this paper, the
writer suggests the strong proba])ility that beneath these mineral-bearing
veins there are intrusions of igneous rock; that the veins were formed
from hot ascending solutions and vapors passing upward to the surface
along crevices which the intrusions formed, but only partially filled. In
the case of the mineral veins of the Kentucky-Illinois district, the dikes
came near, if not entirely to, the land surface as it existed at the time of
the intrusion; but the peridotite in Fayette County, Pennsylvania, ac-
cording to Hice, did not reach the surface. It is found cutting across
the Pittsburgh coal bed, where it was discovered in mine workings, but
dies out in the Pennsylvanian rocks that overlie the coal. The dikes of
Elliott County, Kentucky, are found on tlio surface cutting across rocks
of the Coal Measures, Imt whether or not they readied the surface as it
existed at the time of tlic intrusion is not known. There are no mineral
veins associated with the intrusions, either in Fayette County. Pennsyl-
vania, or in Elliott County, Kentucky, for the reason probably that they
cut sandstone and shale instead of limestone and did not offer the proper
conditions for precipitation and mctasomatic replacement, such as ex-
isted in the Kentucky-Illinois district or on the central Kentucky and
Nashville arches of the Cincinnati ui)lift, where the veins have walls of
limestone.

BUOAI) GEOLOGIC FEATURES

A. R. Crandall recognized the importance of considering the broad
geologic features in connection with the dikes of Elliott County and
pointed out the fact that they are near an east- west anticline which is

482 J. H. GARDNER STRATIGRAPHIC DISTURBANX'E IN OHIO VALLEY

merely a section of the structure discussed in this paper. In the paper
by Dillcr above cited, Crandall is quoted partially as follows:

"The most strikiug modifications of the general dip by transverse flexure is
found along a belt which extends from the Big Sandj' River, south of Louisa.
in liuwrence County, to a point opposite to and but a few miles east of the
dikes. The dip along this belt is to the northward from a ridge of conglom-
erate rock which elsewhere falls below the drainage along the border of the
coal field. It is along this slope that the oil and gas developments of Lawrence
and Martin counties are formd. The px'ominent geological basin centering at
Willard is formed by the junction of the northward dip with the general
southeast dip, increased by local depression. Willard is about six miles in a
direct line northeast of the dike. The dike is found near the juncture of two
lines of flexure : one parallel with the axis of uplift of the Coal Measures and
the other a transverse or secondary undulation of considerable local promi-
nence. Whether or not these conditions throw light on the occurrence of the
igneous rock far from any region of great disturbance, they form an interest-
ing, if not necessary, background to any general view of the dike and its sur-
roundings."

Although not prominent on the surface and having only a very slight
topographic expression, this long line of folding and faulting is deep
seated in its character. There was evidently a yielding of the plastic
under-mass at the time of origin, so that the semi-fluid material far be-
neath the sedimentary series was folded in conformity with the overlying
structure. At points of sj)ecial Aveakuess, where faulting was prominent,
the pressure against the igneous mass was sufficient to force dikes entirely
across the sedimentary rocks to the surface. But at other points the
intrusive material penetrated only to such distances into the overlying
rocks as the pressure, viscosity, and resistance would permit. Where the
dikes found their way to the surface between walls of limestone, as in the
Kentucky-Illinois fluorspar district, ideal conditions existed for the for-'
mation of mineral veins. In the sandstone and shale rocks of the Coal
Measures in eastern Kentucky and in Penns3dvania no veins are found,
and in at least one of the two districts the intrusion did not reach the
surface. So it seems reasonable to suppose that on the central Kentucky
and Nashville domes of the Cincinnati geanticline dikes may have ]:)ene-
trated into the Cambrian and basal Ordovician systems, the pressure be-
hind the intrusions being relieved before the igneous rock reached the
surface, but crevices were formed on upward to the surface, which became
sealed by mineral veins of barite, calcite, and fluorite from ascending
vapors and solutions.

On the accompanying map the names are shown of the difterent sec-
tions of the line of disturbance here discussed, which indicate something

BROAD GEOLOGIC FEATURES 483

of its nature from point to point. Through the literature of the state
geological surveys of Pennsylvania, West Virginia, Kentucky, Illinois,
and of the United States Geological Survey there are numerous refer-
ences that bear on the subject. But the object of this paper is to point
out the connection between known segments and leave the matter of de-
tailed descriptions for a more complete report, which should be prepared
by some one who has the time at his command to assemble the known
data and to make additional observations in the field. It will be found
that the nature of the disturbance varies from a low anticline, with dips
of from 25 to 100 feet per mile in Pennsylvania, West Virginia, and
eastern Kentucky, to a fault zone showing displacements as much as 1,000
feet westward through Kentucky and across southern Illinois.

INDEX TO VOLUME 26

Page

Academy of Natural Sciences of Phila-
delphia, Pennsylvania, Twenty-sev-
enth Annual Meeting of the Geo-
logical Society of America held at. 5

, Vote of thanlis to ... . 110

Acadian Triassic ; Sidney I'owers 93

Adams, F. D., cited on pressure on cylin-
ders of granite 187

— , Memorial of Alfred Ernest Barlow

by 12

ADAPID.E and other Lemuroidea, Obser-
vations on ; W. K. Gregory 153

— • Primates, On the relationship of

the Eocene Lemur Notharctus to
the 419

Affinities of Hyopsodus ; W. D. Mat-
thew .• 152

Africa, Sauropoda and Stegosaurs of

Tendagura of German East 326

A(;assiz, a., a naturalistic model of a
topographic type lirst introduced
into an American museum by SO

— , Keference to views on coral reefs b.y. 78

Agassiz. Louis, cited on coralline alga>. 60

Aoi: of tlie IJed Beds of western Wyo-
ming 229

AiKv, , cited on hypothesis of crust

of the earth 178

Akei:ite (Hypersthone syenite) of Blue

Kidge region, Mrginia 82

Alabama, Crystalline marbles of 104

AMiFUTA Belly Kiver beds ciiuivalent to
.(udith liiver Ix'ds of I)()g Creek and
Cow Island, Montana. Evidence
proving 149

Ai.DEN, \V. C., Discussion of geological

liistory of the Bay of Kundy by. . . 95

Alkxaxduian rocks of northea.steru Illi-
nois and eastern Wisconsin ; T. E.
Savage 95, 155

Ai.c.K of the Ordovician iron ores of

Wabana, Newfoundland, Fossil.... 148

Ai,<;al and bacterial deposits in the AI-
gonkian .Mountains of Montana, Oc-
currence of ; C. I). Waleott 148

Algonkian Mountains of .Montana. Al-
gal and bacterial deposits in 148

Amkhican Association for the Advance-
ment of Science, Address by J. S.
Dlller, retiring Vlce-I'resident of
Section E of the Ill

, Atniiation of Cor-

dilleran Section witli 132

— Scenic and Historic Preservation So-

ciety, ciisiodian of .Tohn Boyd
Thacher I'ark '. . 110

— Social Science Association, "Geo-

graphic sculpture" lirst honored in
this count ry by 80

— 'I'riassic invertebrate faunas and

their relation to those of Asia and

I'lurope 412

Ami. H. M., Discussion of classification

of a<|Meons liabilats by 158

— , ICemarks on crustal movements in

r^ake lOrie region by 67

evidence of recent subsidence

on the coast of Maine by 92

glacial erosion by 73

the origin of thick salt and

gypsum deposits l>y 104

Analyses of obsidian from Iceland,

Tables of chemical 260

Page

Analysis, LithophysiB of the obsidian. 259

Annual dinner of Cordilleran Section
at the Faculty Club of the Univer-
sity of Washington, Seattle 138

— Society at Hotel Walton 104

Anticyclonf.s above continental gla-
ciers. New evidence of the existence
of, axed ; W. H. Hobbs 73

Anthozoa and the systematic position
of Paleozoic corals, Evolution of
the 157

Aqueous habitats, A classification of ;

Marjorie O'Connell 159

Akid erosion, A measure of ; Charles

Keyes 404

Arizona, Bajadas of the Santa Cata-

lina Mountains 391

Arnold, Ralph ; Correlation of the

Lower Miocene of California 415

— , Excursion of California Meeting,

August 14, 1915, in charge of 417

Arundel formation. Reptiles of 337

Aplodontia group. History of ; W. P.

Taylor 417

Asia and Europe Triassic invertebrate
faunas and their relation to the
American 412

Ashley, G. II. ; I'hysiographic study of
the Cretaceous-Eocene period in the
Rocky Mountain front and Great
Plains provinces 105

Asphalt beds of McKittrick, California,
Occurrence of mammal remains in
the 167

Atlantic and Gulf Coastal Plain, Cre-
taceous-Eocene contact in the 168

Atwood, W. W. ; Relation of physio-
graphic changes to ore alterations. 106

— , Speaker at annual dinner 104

Auditing Committee of the Geological

Society 11

I'aleontologlcal Society 146

, Report of 87

Bacterial and algal deposits in the
Algonkian Mountains of Montana,
Occurrence of; C. D. Waleott 148

Bain, H. F.. elected Chairman of Cor-
dilleran Section 131

I'.a.iadas of the Santa Catalina Moun-
tains, Arizona; C. P. Tolman, .Tr. . 301

Baker, , cited on interglacial de-
posits 2.M

— quoted on the Fleming of the Nava-

sota region 460

r.ARP.AGALLO. A., and D. CAitiso, Depth

of Etna crater measured by 3.S.'!

I'.ARLfiw. Alfred Ernest, Bibliogiaphv

of ■. 1.-)

-. Memorial of i:!

. I'liotcjgraph of 1 1'

Bascom, F. ; Magmatic assimilation. . . . K2
- ; Pre-Caiubriau igneous i-ocks of the

Pennsylvania riedmoiit .si

liAsic rocks of Rhode Island : their
con-elation and relalionsliips ; A. C.
Hawkins and C. W. Brown 92

liAsi.v range faulting In (he nortlivvest-
ern oart of the Great Basin; <!. D.
I.ouderback 13s

ItAsiNs within the haniada of the

Libyan desert. Origin of 396

(485)

486

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Page

Bassleu, R. S., Discussion of tlie Tre-

postomata by 158

— , Secretary of ttie Paleontological So-
ciety 141

Bastin, C. S., Discussion of colloidal

migration in ore deposits by 394

papers bearing on ore deposi-
tion by 403

— . Remarks on the Coal Ci-eek batho-

lith by 390

Bay of Fundy, Geological history of ;

Sidney Powers 94

Baylei', VV. S., Remarks on revision of
pre-Cambrian classification in On-
tario by 88

Barrell, JosepHj cited on ancient delta

deposits 221

■ radioactive transformation .... 194

— , Remarks on evidence of recent sub-
sidence on the coast of Maine by. . 92

Barus^ , cited on diabase melting-
point curve 197

Beaches of Lake Algonquin, Battlefield,

and Fort Brady 69

Becker, G. F., Address of retiring Pres-
ident ; Isostasy and radioactivity . .

86, 171-204

— and JoLY cited on difference of

opinion as to age of the earth .... 201
— , President, Telegrams on account of

illness to and from 57

— , retiring President ; Isostasy and

radioactivity 86, 171-204

Belly River beds of Alberta equivalent

to the Judith River beds of Dog

Creek and Cow Island, Montana ;

C. H. Sternberg 149

Berea grit in Ohio, Diastrophic impor-
.tance of the unconformity at the

base of the ; H. P. Cushing 203-216

— • sandstone in Ohio 96, 155, 203-216

Berkky, C. p.. Discussion of basic rocks

of Rhode Island by 92

— - ; Geological reconnaissance of Porto

Rico 113, 156

Berlin Museum, Skeleton of dinosaur

from German East Africa in the. . 153
Bernardixi, L., cited on fumaroles of

Vesuvius 377

Berry, E. W., and Campbell cited

on the Morrison and the Kootenai

formations 305

— cited on Comanchian floras 301

correlation of Potomac forma-
tions 336

the Potomac plants in the Pa-

tuxent formation 304

— ; Paleobotanic evidence of the age of

the Morrison formation. 90. 151, 333-342

— quoted on Morrison and Kootenai

faunas 346

Bibliography of Alfred Ernest Barlow. 15

Horace Carter Hovey 25

• — • — Joseph Le Conte 54

Newton Horace Winchell 31

— • — Kotharctus and Lemuroidea 443

Trepostomata 366

BicKMOREj Albert Smith, Memorial of. is

— ; Photograph of 18

Birds (fossil) of the west coast, Some
problems encountered in the studv

of; L. H. Miller 417

Blackwelder, Eliot ; Origin of the
Rocky Mountain phosphate de-
posits 100

Bohemian- moldavites. Reference to. . . . 265
BOLSOXS, Some physiographic features

of 392

Boltwood, -, cited on lead produc-
tion 190

Page

BORABORA, Tahiti, Coral island model

of 79

BouGUER, Pierre, cited on measurement
of the Peruvian arc and attraction
of Chimborazo 172

Braciiiosalrus, Iteconstruction of the

Skeleton of : \\ . D. Matthew 153

Bic.vxCA, , cited on skeleton of dino-

siuir from German East Africa in
Berlin Museum 15;3

Braxxer, J. C, Chairman Cordilleran

Section 135

— , Discussion of Eocene of the Cowlitz

Nalley, Washington, by lo(i

Geological survey of Brazil and

plans of Oregon Bureau 138

Tertiary sedimentaries and

lavas by 137

— , Faulting in the Great Basin dis-
cussed by 139

I'.raxsox, E. B. ; Origin of the Red

Beds of western Wyoming.. 61, HI 7-230

— ; Origin of thick salt and gypsum de-
posits 103, 231-242

— and D. K. Greger ; Devonian of cen-

tral Missouri 112, 15(i

Bretz, J. H. ; Pleistocene of western

\\ ashington 131

Brewster, , cited on fundamental

laws of the optical behavior of
glass 283

BRiDfiMAX, P. W., cited on pressure on

sealed hollow- cylinders of glass. . . 187

British Columbia, Deformation of the

Coast region of 406

, New species of Ficus from the

interglacial deposits of the Koote-
nay \ alley 159

Br(JG(;er, , Reference to akerites of

Norway described by 82

P.RcKiKLYX channel, Cleveland, Ohio,

The 206

Brown, C. W.. and A. C. Hawicixs ;
Basic rocks of Rhode Island : their
correlation and relationships 92

Brown, E. \V., cited on recent re-
searches on the moon 184

Brown, N. H., Reference to amphibian .
skulls collected in the I'opo Agie
beds of Wyoming by 220

Brown, T. C. ; Evolution of the An-
thozoa and the systematic position
of I'aleozoic corals 157

Brcx's hypothesis on volcanoes cited.. 375

Bryant, A^'. L., and L. Hussakof ; Fish
fauna of the conodont bed (basal
Genesee) at Eighteen-mile Creek,
New York 154

Buffalo Society of Natural Science
Museum, Catalogue of fossil fishes
in the 154

Bulletin, Distribution of 5

BuNSEx, , cited on obsidian analy-
sis 262

Butler, G. M. ; Plea for uniformity and
simplicity in petrologic nomencla-
ture 134

Butte, Montana. Replacement of earlier
sulphide minerals by later sulphides
at 402

r.rwALDA, J. p.. Excursion of Califor-
nia Meeting, August 12, 1915, in
charge of 417

— introduced by A. C. Lawson 403

— . Remarks on geology of portions of

western Washington by 397

— • ; Structure of the southern Sierra

Nevada 403

INDEX TO VOLUME 26

487

Page

Cahokta group of mounds, Monks

Mound lai-gest of 74

Calcium carliouate, Kelation of bacteria
to deposition of ; Karl P. Keller-
man 58

CALii'oitN'iA Coast Hange region. Heave

fault-slipping in the 404

■ — , Correlaliori of tlie Lower Miocene of. 41.5

— Cretaceous floras compared with

those of other Cretaceous areas... 414
Invertebrate faunas, Correlation

of 414

— ; Paunal geography of the Eocene of. 416
— , Fauna of the Lower Montere.v of

Contra Costa County 167

— , Geology of a portion of the Santa

Ynez Hiver district, Santa Barbara

County 401

- — . Note on the ('retaceous Echino-

derms of 166

- — . Occuri-enco of mammal remains in

the asphalt Ijeds of McKittrick ;

X. C. Cornwall 167

— , Itecent eruptions of Lassen I'eak... 105
- — , Review of the Miocene and Oligocene

faunas of 41G

— , Summer IMeeting of the Geological

Society of America, 1915. held in.. 389
• — , Tentative correlation table of the

Neocene of 167

— Tertiary formation. Vertel)rate fauna

in the marine Tertiary significant

in determining age of 108

Cai.ki.vs, F. C, and J. A. Tapf, Excur-
sion of California Meeting, August
10. ]'.»15. in charge of 408

Ca.mi'. C. L. ; E.\tinct toad from Rancho

La Brea 167

Canto.v, New York, topographic quad-
rangle 287

Capellos, Dr. , First descent into

Vesuvius crater made by 378

Caunkv, FitAN'K. cited on glacial erosion

on Kellys Island, Ohio 70

Castdkid.i:. Outline of the history of

tlie ; \V. ]'. Taylor ' 167

CiiADwrcK. G. H. : I'ost-Ordovician def-
ormation in the Saint Lawrence
Valley. Nev.' York 115.287-294

CiiAr.cociTi: in the fluorspar veins of
.leffei-son County, Colorado, pri-
mary : Horace B. Patton 84

CirAi.MKK.s. , cited on interglacial

beds of land and fresli-water shells. 251

Ciiami'.t:i!M\, R. T., Remarks on the
structure of the southern Sierra
Nevada by 404

Cii\Mni:t!i,iN-. T. C, cited on distribu-
tion of compensation by a law. . . . 180

glacial erosion 70

"The shelf seas of the Palezolc

and tlieir relations to dlastro-
phisin" of 306

— and Salisbury's text-book of geology

cited on glacial ion 109

CiiATTANoOGAN series, Kinderhookian

age of the 06, 155

(!nnoNOL(>(;v and correlation on the
basis of paleography ; Charles Schn-
chert 411

Claikaijt'.s and Stokes' theorems on

density of eartlv compai-cd 175

Ci.AlTi C. II.; Det'iirmatinii of the coast

region of Bi-itish ( 'oliiiiihia 406

— (Rocks ne:ir Strut bi-oua. Vancouver
Island, Canada, naiucd Sutton lime-
stone and Wark diorlle l)y S2

Cr.AHic. B. L., Remarks on pisolites at

San .Vntonlo, Texas, l)y 398

— ; Review of the .Miocene and oligo-
cene faunas of Callfoinla 416

^ Page

Cl.^rk, B. L. ; Tentative correlation

table of the Neocene of California. . 167

— and A. C. Lawsox. Excursion of Cali-

fornia Meeting, August 9, 1915, in

charge of 407, 417

Clark, .1. D., introduced by C. F. Tol-

man, .7 r 394

— ; Role of colloidal migration in ore

deposits 394

Cr.AUK. R. B. ; Fauna of the Lower
Monterey. Contra Costa County,

California .' . 167

Clark, W. B.. cited on Potomac inver-
tebrate fauna ;',4;">

— , Report of Treasurer 8

("LARKE, .1. M. ; Causes producing
scratched, imiiressed, fractured, and
recemented pebbles in ancient con-
glomerates 60

— , Chairman of First Section 90

— .Discussion of Acadian Triassic by.. 94
classification of aqueous habi-
tats by 158

I'aleozoic stratigraphy about

Three Forks, Montana, by 157

Shawangunk formation of Me-
dina age by 150

— , Discussion on ancient man by 149

— , Member of Auditing Committee. ... 11
— , Memorial of Horace Carter Hovey

by ■. 21

— ; Pic D'Aurore section 150

— ; Typo of rifted relict mountain, or

rift-mountain 90

— and W. D. Matthew; Peccaries of

the Pleistocene of New York 150

Clarke's '"Data of Geochemistr.y," Cita-
tions from 233

Cli.matic oscillations, Grapliic projec-
tion of Pleistocene ; C. A. Reeds. . . 106
Clixe, .T. H., and T. L. Watsox ; Hy-
persthene syenite (akerite) of the
middle and northern Blue Ridge

region, Virginia 82

Clevelaxd, Ohio, Natural gas at 102

Coal Creek batholith, Geologic age and
geology of the Colorado Front

range 398

Coal field of Pierce County, Washing-
ton, Structure of 132

— fields of New Mexico, Certain struc-

tural features in the; C. T. Kirk.. 405

— Measures. Scaled amphibia of the... 154
CoALixGA east side field. Relations of

the Santa Margarita formation in
the IGC.

— district. Fauna and relations of the

white shales of the 168

Coast of Maine, Evidence of recent sub-
sidence on the 91

CocKKREr.L, T. D. A. ; Flora of florissant. 416
CoLE.MAX. A. P., cited on rate of wave
erosion on the shores of Lake On-
tario and glacial Lake Iroquois.... 107
— ; Length and character of the earliest

Interglacial period 243-254

Colorado Front Range geology and geo-
logic age of the Coal Creek batho-
lith .-{OS

-—.Occurrence of flow-breccias in 390

— Plateau province. Wind sculpture of

rock in 303

— , Prinuiry chalcocile in 84

— , Recent renuirUalilc gold "strike" at

the Ci-esson mine. Cripple Creek.. 84

— and .New Mexico. Relation of Creta-

ci'ous formations to the Rocky

Mountains In 114. 150

Colloidal migration in ore deposits.

Role of ; .1. D. Clark 394

488

BULLETIN OP THE GEOLOGICAL SOCIETY OF AMERICA

Page

Co.MANCHEAN of Chamberliii and Salis-
bury, Reference to 307

Comparison of marine vertebrates of
western North America with those
of other Triassic areas ; J. C. Mer-
riam 413

the Cretaceous faunas of Japan

with those of western United
States ; H. Yabe 414

— floras of California with those

of other Cretaceous areas ; F. II.
Knowltou 414

CoNGi.oMiaiATKS. Causes producing
scratched, impressed, fractured, and
recement.ed pebbles in ancient ; .1. M.
Clarke 00

CoxN'KCTicuT, I'yrrhotite, norite, and

p.vroxenite from Litchfield S3

CoxoDOXT bed at Eighteen-mile Creek,

New York, Fish fauna of the 154

CONTIXENTAL glaciation. Evidence of... 78

— glacier in central Illinois, Glacial

erosion near margin of 70

Cope, E. D., cited on description of the
famous skull '•AnaptomoriJhus''

homiiiiriilits 430

COPPEH ores. Examples of progressive
change in the mineral composition

of ; C. F. Tolman, .Tr 394

Coral Island theory. Comprehensive ;

G. C. Curtis 78

— reefs and platforms. Various locali-

ties of .",0

. ■ — reef corals of the southeastern

United States, their geologic his-
t o r y and significance ; T. \V.

Vaughan 58

of Florida 59

Corals as constr\ictional geologic

agents. Summarized statement of . . 59
— , Evolution of the Anthozoa and the

systematic position of Paleozoic... 157
Cordii.leran Section, Proceedings of . . .

129-140

, Kegister of the Seattle Meeting. . 140

.Visitors and other geologists tak-
ing part in the meeting of the. . . . 140
CoRxw.VLL, N. C. : Occurrence of mam-
mal remains in the asphalt beds of

McKitlrick, California 107

CoRREi.ATiox and chronology- on the
basis of paleography ; Charles Schu-
chert 411

— between invertebrate faunas of Cali-

fornia and those of Mexico ; E. L.
Packard 414

the Cretaceous of the Pacific area

and that of other regions of the
world : T. W. Stanton 414

— middle and late Tertiary of the

South Atlantic coast of the TTnited
States with that of the I'acific
coast : E. 11. Selhirds 41(')

— Miocene of the Pacific region

and that of other areas of the
world. Topic of California Meeting
of the Paleontological Society, Au-
gust 6, 1915 415

terrestrial Triassic forms of

western North America and Eu-
rope; R. S. Lull 413

— -of Miocene, Introductory remarks

on ; H. F. Osborn 415

the Cretaceous invertebrate faunas

of California ; T. W. Stanton 414

. — • .Topic for the California

Meeting of the Paleontological So-
ciety, August 5, 1915 414

Lower Miocene of California;

Ralph Arnold 415

Page
Correlation of the Miocene floras of
western T.'nited States with those
of other Miocene areas ; F. H.

Knowlton 416

Tertiary formations in western

Washington ; C. L. Weaver 170

■ — Triassic, Symposium for Cali-
fornia Meeting of the Paleontolog-
ical Society, August 4, 1915 415

Correspondents, 1914 118

— , Deaths reported of, 1914 5, 12

— deceased 127

CoRRV sandstone. Marine fauna in 210

Council, Report of 5

Cowlitz Valley, Washington. Eocene of

the 136. 169

Cu.\ XDALL, A. K., quoted on dikes of

Elliot County, Kentucky 482

CuATKR, Kilauea, a drop-fault 77

CitAWPORL), 1{. D., cited on flow-ljreccia. 4()(i
Cretaceous age of the Potomac group

indicated 330

— and Eocene time in North America.

Ueference to 29."'(

— Echinoderms of California. Note on

the ; W. S. W. Kew 100

— Eocene contact in the Atlantic and

Gulf Coastal Plain ; L. \V. Ste|ihen-

son 108

period in the Rocky Mountain

front and Great Plains provinces,
I'hysiographlc study of 105

— faunas of .Japan compared with those

of western United States : H. Yabe. 414

the Santa Ana Mountains:

E. L. Packard 109

— floras of California compared with

those of other Cretaceous areas ;

V. H. Knowlton 414

— formation. The Morrison, an iuitial..

90, 151, ."{03-314

— formations. lielation of, to the Uocky

Mountains of Colorado and New
Mexico ; W. T. Lee 114. 150

— invertebrate faunas of California.

Correlation of: T. W. Stanton.... 414
--of the Pacific area: correlation be-
tween it and that of other regions

of the world ; T. W. Stanton 414

— . Kecent work on the dinosaurs of the 41i>

— stratigraphy, Upi)er 149

— , Symposium on the passage from the

.lurassic to the 90, 151

— time in North America, Close of .Tu-

lassic and opening of; H. F. Os-
born 295-.302

Ci;i;ssox mine. Cripple Creek. Colorado,

Recent remarkable gold "strike" at. 84

Cripple Creek, Colorado, Recent re-
markable gold "strike" at the Cres-
son mine 84

Criteria of correlation from the point
of view of the invertebrate paleon-
tologist ; E. O. Ulrich 410

Criiuk. a. U. ; Origin of Monks Mound. 74

Cross. Wiiitmax, cited on forms of ig-
neous rocks of the San Juan Moun-
tains of Colorado 399

— . Discussion of gold "strike" at Cres-
son mone. Cripple Creek, Colorado,

by 85

(juoted on flow-breccia 400

the production of lithophysiP. . 256

— . Ivemarks on effects of ])ressure on

rocks and minerals by S4

— and L\RSK\ (luoted on connec-

tion of Morrison and Gunnison

l)eds 311

Cuistal movements in the Lake Erie
region. Preliminary paper on re-
cent ; Charles E. Decker 66

INDEX TO VOLUME 26

489

Page

Crystallixe marbes of Alabama ; W. F.

I'routy 104

Culver, II. C. Paper of F. M. Handy
ou role of sedimentation in dias-
trophism and vulcanism read by.. 138

CUiMiNGS, E. U., and J. J. Galloway ;
Studies of the morphology and his-
tology of the Trepostomata or Mon-
ticuliporoids 158, 349-374

Curie, Madame, cited on value of heat-
ing effect of radium 195

Curtis, (i. C. ; Age as the determinant

of character in volcanoes 78

— ; Comprehensive coral island theory. 78
— ; Kvidence of continental glaciation

on Mount Katahdiu 78

— introduced by E. <). llovey. . . . 77, 7S, 79

— ; KUauea, A drop-fault crater 77

— ; Naturalistic land model, the "last

word in geology" 79

Cu.siii.\<;;, II. P., cited on undulation of
Paleozoic rocks for the Watertown
district :i87

— , Chairman Third Section 81

■ — ; Diastrophic importance of the un-
conformity at the base of the Berea
sandstone in Ohio 96, 155, 205-216

• — , Discussion of Hamilton group of

western New York by 113

North American continent in

Upper Devonic time by 90

revision of pre-Cambrian classi-

lication in Ontario by 88

- — , Manuscript on Ogdensburg quadran-
gle of 288

— and I'LRiCH cited on refinement

of stratignipliic units in Canton
<iuadraugle 288

Cv.sr.s and brown bodies of Treposto-
mata 351

Cystiphragms of the Trepostomata 350

I).v(j<;ett. F. S., and .T. C. Mekriam, Ex-
cursion of California Meeting, Au-
gust 13, 1915, in charge of 417

Dakota sandstone 311

Dai.l, W. 11., Inverteljrate fossils of
Purkcville localit.v, Te.xas, sub-
mil led to 469

Dalv, U. a., l)iscussion of pliysiographic

control in the I'hilippines by 396

— ; Orisiri of llie iron ores at Kiruna,

Sweden 99

— , Sidney Powers introduced by 93,94

Daniels, .Iusei'II ; Structure of I'ierce

County coal field of Washington... 132

Dakto.v, N. II. ; Extension of Morrison

formation into .New Mexico 113

— (juoted c)M Ked l'.eds of Wyoming. . . . 218

— , Ueporl of Photograph Committee... 57

Daiswin, Charles, Uefereiicc to sub-
sidence theory of coral atoll for-
mation 78

Darwi.n, Ceorce II. and IIouace, cited
on first attempts to measure bodily
tides in tlie eartli 172

Darwi.v, 1I(jrai'e and (lE<iit<!i'; 11., cited
on first attempts to mcasuri! bodilv
tides in the earth '. 172

Davis, C. .\., Discussion of algal and
bacterial deposits In the .Mgouklan
Mountains of .MoiiiMiiii by 14N

glacier erosion by 73

— ; Evidence of recent subsidence on

the coast of .Maine ill

Davis, E. P., and .\. C. EAWSdN. i;x
curslon of California .Meeting, Au
gust (J, 1915, In cliarge of i(t7

Dawso.v, - — -. cited on two species of

(li»k(j<i 339

Page
Day, a. L., John .Johnston introduced

by 83

— and H. S. Washington ; Present con-

dition of the volcanoes of southern

Italy 105. 375-388

Shepherd cited on studies at

KUauea 375

Decker, C. E. : H e m i c o n e s at the

mouths of hanging valle.vs 7<)

— introduced by Richard U. Hice. . . . (it), 76

— ; Preliminary paper on recent crustal

movements in the Lake Erie region. 66
De Fiore, O., cited on eruptions and

bibliography of Vesuvius 376

r>EFOR.MATioN of the coast region oi

British CoUimliia ; C. II. Clapp. . . . 4(i6
1)E L.vppARENT, . cited on classifica-
tion of later .Jurassic sediments fol-
lowing Oxfordian 347

Density of the earth 173

Desert, Epigene profiles of the 391

— ranges. False fault-scarps of 65

— sand-blast, Limited effective vertical

range of the ; W. H. Holtbs 396

Deussen, Alexander, introduced bv .L

A. Taep 398

— ; Pisolites at San Antonio, Texas. . . . 398
— , Remarks on the Texas Tertiary

sands by 39s

Devon LIN of central Missouri; E. B.

Branson and D. K. Greger. . . . 112. 156

Devonic fish faunas, Most remarkable

known 154

Diastrophic importance of the uncon-
formity at the base of the Berea
sandstone in Ohio; II. P. Cushing.

96, 155. 205-21 (•>

Diastrophism and vulcanism. Role of

sedimentation in 138

— of the Pacific coast, Topic C, Sum-

mer Meeting in California, 1915. . . 390
Dice, L. R. ; Rodents of Rancho La

Brea 167

DiCKERSON, R. E. ; Faunal geography of

the Eocene of California 416

— ; Fauna of the Siplionalia Sutterensis

zone in the Roseburg quadrangle.
Oregon 169

-^ ; lone formation of the Sierra Nevada
foothills, a local fades of the Upper
Tejoil-Eocene 168

DiCRiioosAtRus Janensch. Description of 329

1>ILLEI{, .1. S., Address as retiring \'ice-
I'resident of Section E of the
American Association for tlie Ad-
vancement of Science Ill

— ; Recent eruptions of Lassen Peak.

California Iti"'

— ; Relief of onr Pacific coast Ill

— and R. S. IIoi-way ; Characteristics

of the Lassen Peak eruptions of
.May 20-22. 1915 397

Dinner of the California Meeting of the
Paleontological Society with the
(Jeological Society at the Engi-
neers' Club, in San Francisco, Au-
gust 4. 1915 41.-;

Geological, Paleontological, and

Seismological Societies. Summer
Meeting, 1915. at Engineers' Club. 395

Society. Annual KM

Dinosaur, Skeleton in Berlin Museum

of 15::

, Skeletons of largest known 15.'!

DiMisAlitlAN societies. Three vistas of. 327

DiNiis.M us. Mlgratorv roads of Sauro-

pod and Stegosaur 326

of the Cretaceous. Recent work on;
II. F. O.sborn 416

— , Perdentate 329

. Sauropod and Stegosaur 324

490

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Page

DiORiTE of Vancouver Island, W'ark... S:.'

Dixox, Dr. Sami'EL (J., visiting geolo-
gists and paleontologists welcomed
to the Academy by 5

Dole, R. B., Precipitation of calcium
carbonate and formation of oolites,
reference to 58

Dolomites, New points on origin of;

P. M. Van Tuyl G2

D'Orbig.vy, , cited on classification

of last stage of the Jurassic sys-
tem L>OS

Drew, G. II., Precipitation of calcium
carbonate and formation of oolites,
reference to ,58

DisiFTLESs area. Physiographic studies

in the 70

Dr.MHLE, E. T. ; Problem of the Texas

Tertiary sands :'>08. 447

E.VRTii. Density of the 173

Eaisth's radiation 19.5

EcHiNODER.Ms of California, Note on the

Cretaceous KiO

Editor's report 10

Egleston, T., Reference to his discus-
sion of ei-osion by sand-blast 64

Electiox of Auditing Committee, Geo-
logical Society 11

Fellows 12

Officers. 101.-. 11

and Meml)ers of the Paleonto-

logical Society 146

of Cordilleran Section, 1014-

1015 i;!l

E.MMONS, B., cited on example of crump-
ling 294

E.M.MO.vs, W. H., cited on the Jurassic

movement 311

— , Discussion of platinum-gold lode de-
posit in southern Nevada b.v 85

— quoted on stratigraphy of the Morri-

son 310

— . Remarks on effects of pressure ou

rocks and minerals b.v 84

— organic origin of some mineral

deposits in unaltered I'aleozoic sed-

nients by 86

l)yrrhotite, norite, and pyroxe-

iiite from Litchfield, Connecticut.

by 395

Eocexe and Cretaceous time in North

America. Reference to 295

- (faunal) of California, Geography of:

It. E. Dickerson " 41G

— Lemur \(jthar<tiis. On the relation-

ship to the Adapida' and to other
primates of the; W. K. iiregory. . . 410

— of the Cowlitz Valley, Washington ;

C. E. Weaver 136, 160

— period in the Rocky Mountain front

and (ireat Plains provinces. Physi-
ographic study of the Cretaceous. . 105

Epeiroge.vy. Note on 188

Epigene profiles of the desert ; A. C.

Lawson 301

Rrosio.v, a measure of arid 404

— and deposition in arid climates. Topic

A. Summer Meeting in California,

1915 ■ 300

— , Glacial 70, 78

— in Libyan desert, sand-blast 63

Europe and Asia Triassic invertebrate

faunas and their relation to the

American 412

— , Migration and succession of human

types of the old Stone age of 140

— (western) as a factor in the war,

Physiographic features of 110

Page

El Roi'KAx Jnrassic-Cretaceoiis division

line 296

Etna. Height of summit crater of

Mount 381

— , Last great eruption of and refer-
ence to descriptions of 381-382

Eve, , cited on recent researches on

atomic structure in science 101

Evolutiox of the Anthozoa and the
systematic position of Paleozoic
corals ; T. C. Brown 157

ExriRSioxs made by members of the
California Meeting. August, 1015..

407, 417

Expexditeues 9

airchild, II. L., cited on ice erosion

a fallac.v

~, ^lember of Auditing Committee. ....
-. Memorial of Joseph Le Conte by. . .
AiR.MoxT, Illinois, limestone quarrv...
Ari/nxG in the Great Basin, Basin

range

'AfLT-scARps of desert ranges, False;

Charles Keyes

"ault-slippixg in the California Coast

Range region, A possible causal

mechanism for heave ; H. O. Wood.
'auxa and relations of the white shales

of the Coalinga district ; J. II.

Ruckman

in the marine Tertiary of California,

Vertebrate

- of Eighteen-mile Creek, New York,

Fish

the Lower Monterej' of Contra

Costa County, California ; B. L.
Clark

Morrison, The invertebrate. . . .

90. 151, 343

Rattlesnake Pliocene of eastern

Oregon. Review of the ; J. C. :Mer-
riam

Siphonalia Sutterensis zone in

the Roseburg quadrangle, Oregon ;
R. E. Dickerson

-, Tribes Hill or Lower Beekmantown
and Bucks Bridge

-, Wealden, I'otomac, Kootenai, Bear
Uiver, Dakota, Sundance, and
Washita invertebrate 344

'At'NAL and stratigraphic relations of
the later Eocene of the Pacific
coast ; Harold Hannibal

Lincoln formation in

Washington ; C. E. Weaver

-geography of the Eocene of Cali-
fornia : R. E. Dickerson

'AiXAS (Cretaceous) of Japan and
western LTnited States, Comparison
of

- (invertebrate). Correlation between

those of California and Mexico. . . .
of the American Triassic : rela-
tions to those of Asia and Europe.

- of California. Review of the Miocene

and Oligocene

the Morrison, Comparison with

other non-marine invertebrate

Pacific Coast region. Verte-
brate ; J. C. Merriam

Santa Ana Mountains. Cre-
taceous

ELLows, Deaths reported of. 1014 ... 5

- of Geological Society. 1014

deceased

'EXXER, C. N.. cited on crystallization

temperature

-, Discussion of Acadian Triassic by . .

70
11
47

138
65

404

168
168
1.54

167
348

160

160
280

348

168
169
416

414

412

416

344

416

169
. 12
118
127

269
94

INDEX TO VOLUME 26

491

Page

Fenneu, C. N., Discussion of effects of

pressure on rocks aufl minerals by. 84

on gold "strike" ;it Cresson mine.

Cripple Creek. Colorado. I).v X"i

Fekgisox, .T. B.. Clieniical analysis of

black ()l)sidian fro)H Iceland l>y . . . . -'>'.<

Fkkmok. Lkiiiii. cited on radioactiye

transformations I'-'-l

Fins from tbe interulacial deposits of
the Koolenay Valley. I'.rilisli Co-
himliia. New species of: .\rtluir
llo'.lick '•"'''

KilOLi) Museum. Cliicago. Skeletons of

largest known dinosaur in 1">">

Kisn fauna of the conodont l>ed (Basal
(ieueseel at Eighteen-mile Creek.
New York; L. llussakof and \V. I..
Bryant 1-1

FiMiKK, C. A., cited on Ivoolcnai and

Morrison formations ">^1

the relation of Itic .Mm-iisou lo

the Ivooteuai •'!•'■+

FbouA of Florissant : T. 1 >. A. Cockercll. 41(1

FLoitAS ( t.'retaceonsi of <'alifornia com-
pared with those of other Creta-
ceous areas 411

Fi.or!ii;.v. Stratigraijhic relations of the

fossil vertebrate localities of 1">4

Floimssaxt, Flora of : T. D. A. Cock-

erell 4ic.

Fl.uw-iaiMrci.vs in Colorad(j. Occurrence

of ; n. B. Paltou 390

Fi.inusi'Ai: veins of .lefferson County,

Colorado. I'riniary cha'.cocite in tbe 84

F'ii;i;sTt:. A. F.. Discussion of Hamilton

group of western New York by. . . . llo

Fossil, algie of tbe Ordovician iron ores
of Waljana. Xewfoiindlaml : ''.. \'au
Ingen US

— birds of the west coast, iSonu' prob-

lems encountered in the study of:

I,. II. Miner 417

— vertebrate localities of I" 1 o r i d a.

Stratigrapbic relations of the l-"i4

Fiiin;. K. F.. I'hysiographic features of

bidsons discussed liy '■>'■<■'•

Fi! IEIH..\.NI)KI!. I., cited on "repose" cun-

diiions of \'esuvins :iTi!

FiMAi; il.lvs of Vesuvius. I'eri-et. .\lei-

calli. Malladra. and Friedliindef

cited on teiu]ieralure of ."TT

FiNA l'"i ri lioring. \V. T. Vaigban 011.. <>(i

Gaeta.no F'l.Ai'AMA quoted on activit.y
of SIromboli

tlAi.i.oWAV, .1. .1.. and F. 1!. CtMi\'f;s;
Studies of the morphology and his-
liih)gy of tbe 'rrep"st">'nata or Mon-
t iculii)oroids 1.58, .''«4b

Caiiunki!. .1. II.; A stialigraiibic dis-
iMi'liance tlirougb (he (lliio \'alley.
running from the Appalachian IMa-
leaii In Pennsylv;ini:i lo the O/.ark
Mountains in .Missoui-i (Wl,

- — ;(>il pools of southern Oklahoma and
northern Texas

Oa.s at Cleveland. Ohio. Natural

(iioiGEit. B.. cited on intensity of earth-
finake waves

"(iKo'iitAi'iiic scidpture" first lionored
In this country- by the American
Social Science Association

Geologic ape of the Coal Creek hatlio-
lith and its bearing on some other
features of the geology of the Colo-
rado Front Kang*' ; Ilyrum Schnei-
der

— deposits In relation to I'leistoccne
man ; C. A. Reeds

387

-.■'."4

loi:

,S(t

398
109

Page

lEOLOGic structure in western ^Vash-

ington ; C. K. Weaver lo.'

!i;(ii,(><;i(Ai, reconnaissance of I'orto

Kico : C. P. Berkcy li;j. l.")<>

Ikoeooy of portions of western ^Vash-

ington ; C. E. \Veaver 3'.t.

;i:sTi:i!. G. C. : Geologv of a portion of

the McKittrick oil" field Itlb

JiiiivEV. .T. W., Discussion of fossil ver-
tebrate localities of I'Morida by. . . . B"'>4

the affinities of the Mnititnber-

culata by l.">-

JiiJiERT. <J. K., cited on irregular dis-
tributions of density 184

iiL.MOtti;. C. W.. cited on dinosaurs of

post-Morrison formation 340

iiKTY. , Reference to faunal list of

the Corrv sandstone formation pub-
lished Ixv :;io

;i..\c'iAL erosion near tile margin of the
continental glacier in cenii-al Illi-
nois, Some peculiarities of; .lobn
B. Rich TO

iLAijATio.v on Mount Katahdin, Evi-
dence of continental 78

li.ACiER in central Illinois, Glacial ero-
sion near continental 70

;oi,DS(;'HjriDT, v.. and F, E. Wright
cited on abrasive action of sand-
laden winds -79

ini.ii "strike" at the Cresson mine.
Clippie Creek. Colorado, Recent re-
markable ; H. B. Patton 84

telluride ore. Cripple Creek, Colo-
rado 84

;i:ai-.ai'. a. W.. cited on principles of

stratigraphy 231

— . Discussion of Alexandrian rocks by.

0.5, 1.-J.J

Hamilton group of western New

York by 1 13, 158

Paleozoic stratigraphy about

Three Forks, Montana, by 157

Red Beds by 61

Shawangunk formation of Me-
dina age by 150

-; Hamilton group of western New

York 113, 158

; Xorlh American continent in Fpper

I •eviinic time 88

; (Xentangy shale of central Ohio and

its stratigraoliic signiticance. . 112,150
, Reference to Louis Agassiz of impor-
tance of coralline alg;p by 60

— . Remarks on Nagelflub of Salzburg

by 61

— - re(|uested fo give two papers listed

luider the Pal<'()ntological Society's
iiriPUi-.-im 112

-- . rncouformily at tbe base of the
P.crca sandstone in Ohio discussed
by 06, 1.55

< ;i;.\.\Gi:i;, \Vai,ii:i;, cited on discovery of
specimens of Xutliiiicl lit In the

Middle lOocene of Wyoming 421

. Itiscussion of Sauropod dinosaurs b.v lo."'.
: .New exidence of the alliiiities of tile
.Mull iiulierculaia 152

Ciii.vi P.iisin. Basin range faulting in

the 13S

Plains and Pocky Mountain Front
pi-ovinces. Physiographic study of
the Cretaceous-Eocene period in the 105

(JitKiii u. D. K., and l). B. Bkansox ; De-
vonian of central Missouri... 112,156

GuEooitv, H, E, presided at meeting

First Division 62

■ - ; .Sculiiturlng of rock in the Colorado

Plateau proxiuce 303

— ; Some physiographic features of bol-

sons 392

492

BULLETIN OP THE GEOLOGICAL SOCIETY OF AMERICA

Page
(tKEGoii'i , W. K., Discussion of tlie affini-
ties of llie Multitubereulata l).v. . . . 152

— ; Observations on Adapida' and otlier

Leninroidea 153

file phylogeny of tlie higlier

primates 153

— ; On tile classification and phjiogeny

of the Leninroidea 426

relationship of the Eocene Le-
mur XdtlKirctiis to the Adapidce
and to other )irimates 419-425

— , Paper of U. L. Moodie presented

and discussed by 154

Group A. First Section : Iiynamic,

Structural. Glacial. Physiograi)hic. 01

Grouxu-si.oiiis. Megalocnus and other

Cuban 152

GuTENBEHG, 15. . cited on intensity of

earthquake waves 172

Gypsum deposits, Hypothesis for the

origin of 223

of the upiicr lied Beds of Wyo-
ming 240

— — , Origin of tliick salt and. 103,231-242

Hajiada of file Libyan Desert, Origin

of the basins within the 390

Ha.mii.ti).\ group of western Xew York ;

A. W. (irabau 11:;, 15S

Handy. F. :\I. ; Kole of sedimentation in

diastrojiliisni and vulcanism 138

HAXXtHAi-. llARoi.L): Stratigraphic and
fauna 1 relations of the later Eocene
of the Pacific coast 108

Harvard Museum of Comparative Zool-
ogy, The coral island model of
Borabora. Tahiti, installed in 7!)

Hatcher. .T. B.. cited on collection of
dinosaur bones in Carnegie Museum
at I'ittsburgh 340

— dinosaurs deiiendent on one pe-
culiar type of habitat 327

on the origin of the Morrison

formation 319

Hauer and Weiss cited on lithophysa?. 256

Haug. E., (juoted on extension of last

staae of .lurassic system 298

— and H. B. Woodward cited on rela-

tions of the .Jurassic and the Cre-
taceous in Wiltshire. England 298

Hawkins, A. C, and C. W. Brow.v :
Basic rocks of Rhode Island : their
correlation and relationships '.i2

Ha WORTH, Erasmus. Informalion asked
how to distinguish flow - breccias
from other t.vpes of lireccia b.v. . . . 4(tl

— , Physiographic features of bolsons

discussed b.y •".9:;

— , Remarks on the Coal Creek batholith

by :•.!>'.•

Hayford. J. F., cited on "tlie Pratt-
Hayford hypothesis'" establishing
isostas.v 179

— and Bowie cited on topography and

isostatic compensation 181

Bowie's formula of value of

gravit.v at sealevel 181

Haynes, W. p. ; New facts bearing on
the Paleozoic stratigraphy of the
region about Three Forks. Mon-
tana 157

Heads and tails ; a few notes relating
to Sauropod dinosaurs ; W. J. Hol-
land 153

Heave fault-slipping in California Coast

Range region 404

Hecker. O., cited on voyages to deter-
mine Intensity of gravity at sea. . 183

Helderberg escarpment as a geological

park 110

Page
lEi.if.M. Development of 190

— of ("arnot spring, Santenay and Cesar

sjiring. Nevis 193

Iel.mert, F. R., cited on pendulum ob-
servations 174

Hel.mert's formula of value of gravity

at sealevel 181

Ie.micones at the mouths of hanging

valleys ; C. E. Decker . . . 76

Ieuschel. Sir Johx, and Charees
Bai'.hage cited as first to indicate
tendency to isostasy 178

Ieiveltox formation of the Canton,

Xew York, quadrangle 289

IiCE. R. R., C. E. Decker introduced bv.

00, 70

—, Discussion of crustal movements in

Lake Erie region by 07

Del, Robert T.. Commuted for life. . 8

Iitchcock. C. H.. Remarks on State

Survey methods in New England by 138

— ; Tertiary rocks of Oahu 133

Hours. W. H. ; Limited effective vertical

range of the desert sand-blast,
based on observations made in the
Libyan desert and in the Anglo-
Egyptian Sudan 396

— : Xew evidence of the existence of
fixed anticyclones above the conti-
nental glaciers 73

— ; Origin of the basins within the

hamada of the Libyan desert 396

— ; Bange and rhythmic action of sand-

blast erosion from studies in tlie
Libyan desert 63

— , Bemai-ks on physiographic control in

tile J'hilippines bv 390

IIoLDEX. U. .!., Fellovv-elect 110

HuLi.AXD. W. J.; Heads and tails; a
few notes relating to Sauropod
dinosaurs 15;*,

lliiEEicK, Arthur: Xew S))ecies of
Ficus from the interglacial deposits
of the Kootenay Valley. British
Columbia 159

HoEMEs. Arthur, cited on radioactive

transformations 194

— and Rutherford cited on esti-

mate for amount of radium in

rocks 196

IliPi.WAv, R. S.. Discussion of epigene

proliles of the desert by 391

— . Remarks on the structure of the

southern Sierra Nevada by 404

— . Excursion of California Meeting. Au-
gust 7. 1915, in charge of. . 407

— and J. S. DiELER ; Characteristics of

the Lassen Peak eruptions of May

20-22. 1915 ■. 397

lliii'Kixs, W., cited on thickness of

earth's crust 178

IlnTEi, Wai,tox', Philadelphia, Annual

dinner at 104

HovEY, E. O., Acting Secretary of First

Section 61

Third Section 99

— . A. K. Lobeck introduced by 77

— , (t. C. Curtis introduced by 77

— . Report of Secretary 5

— -. Toastmaster at annual dinner 104

lIovEY. Horace Carter, Bibliography

of ". 25

— . Memorial of 21

— . Photograph of 21

Howe. Erxest ; Pyrrhotite. norite, and
pyroxenite from Litchfield. Con-
necticut 83

— , Secretary of Third Section 81

Hrafxtixxtihryggur obsidian, Descrip-
tion of the 258

INDEX TO VOLT ME 26

493

Page

Human types of the old Stone age of
ICurope, Migration and succession
of 141)

HrssAKOK, I... and W. L. L'.uyant ; Fisli
fauna of tlu» conodont bed (basal
Genesee) at Eighteen-mile Creek,
New York 154

lIi'TTox. ("iiAKiJis, cited on method of
dissecting a mountain mass into
elements 17;i

• Sclieliallien and Cnvendish

methods for determining density. . . 17;j

IlYDiiciTiiFnMAi, mineral. Sericite, a low

temperature 39")

Hvoi'soDis, Attinities of 152

llYi'EKSTHENK syenite (akerite) of the
middle and nortliern I'.l\ie Itidge
i-egion. \'irginia : 'l\ li. \\'atson and
.1. II. ('line S2

ICELANDj Oljsidian from llrafntinudh-
ryggur ; its lithophysa> and mark-
ings 255

Idpixcs, J. 1'., Analysis of the litho-
physa- of obsidian (Miff, Yellow-
stone National Park 259

— cited on sijhcrulitcs or lithophysse of

Yellowstone National Park 255

— quoted on igneous rocks and flow-

lireccias 401

the lithophysa' in the Obsidian

("liff splierulites 25G

Ic.N'Eou.s rocks. I'ennsylvania Piedmont

pre-( "amiirian 81

Ili.i.nois, Alexaudi-ian rocks of north-
eastern 95, 155

— , Fairmont limestone cjuai')'y in 70

— , Glacial erosion in central 70

— .Sketch map locating Fairmont
quarry with resi>ect to limit of

eai'ly Wis<'onsin glacier 71

I.\Fi;xi)iKri,Ai: diaphragms 351

IxTi:Ri;i,ACiAr, deposits in other places

than the l)on and Scarboro beds.. 251

— period. Length and character of the

earliest: A. P. Coleman 243-254

— time. Length of 252

I.\VEii'ii:nuAii: laumi of the MoriMson ;

T. W. Stanton 90, 151, :543-34S

, Lists of described spe-
cies of the 343

- — faunas of .Me.xico. Correlation be-
tween tliose of California and the. 414
. — the .American Triassic : rela-
tions to tliose of Asia and I-hwope;
.7. I'. Smith 412

— paleoiilolniiisi. Criteria of coi'relation

from the point of view of the 410

Ixvi;srMi:xrs 8

loxi-; formation of the Siei-ra Nevada

foothills, a local facies of the I'p-

per Te.jon-IOocene : IJ. !•]. Dickei-son. lOS
Ikon ores at Kirnna, Swe<len, Origin of

the !".)

ISDsr.vsv ;ind radioactivity; G. I'.

ItecUer SO, ]71-2(j4

— , Premonitions of 172

Itaia', Pi'esent condilions of the vol(a-_ _

noes of southern 105, ;{75-3S,S

.Taxaxscii. . cited on skeleton of

dinosaur from (Jerman East Africa

In Iterlin Museum 153

— quoted on I'raas's view that O. nfri-
iiniiis accords with the North Amer-
ican genus Diplddociis 329

.Tatan Cretaceous faunas compared with

those of western T'nifed States.... 414

— , Triassic deposits of : H. Yabe 113

Page
.Toirx P.iivi) THACiiEit Park: The Hei-
delberg escarpment as a geological

park : G. F. Kunz 110

.ToHX Day Valley, Fauna of 169

.ToHXsox. D. \\., Acting Secretary First

Section 90

— , Evidence of recent subsidence on the

coast of Maine analyzed b.v 92

— ; I'hysiographic features of western

Europe as a factoi- in the war 110

.luiixsTox, JoHX, Introduced by A. L.

Day 83

— , Itemarks on blood of oysters and

other animals contains copper by, . 8fi
— ; Some effects of pressure on rocks

and minerals 83

.ToLV, , cited on mode of origin of

ui-aniiun and thorium 194

— and RuTHEUFORD cited on means

devised for estimating the age of
rocks 190

.lo.XEs, .T. C.. Discussion of Triassic

faunas by 412

■ — introduced by .T. C. Merriam 392

— ; Origin of the tufas of Lake Lahon-

tan 392

— , Physiographic features of bolsons

discussed by 393

— . Ueniarks on the Lassen Peak erup-
tions by 397

.T(>f:\ai>a del MiEUTO, Ueference to

faidt-scarps of 65

.TcHAssic and oi)ening of Cretaceotis
time in North America, Close of:
II. F. Osborn 295-302

— to tlie Cretaceous, Symposium on the

passage from the 90, 151

Keith, Akiiiir. Report of (Jonimittee

on Geological Nomenclature by. ... 57

Keli.ekmax, Kake F., Relation of bac-
teria to deposition of calcium car-
bonate by 58

Kew. W. S. W. ; Geology of a portion of
the Santa Ynez River district,
Santa Karliai'a County. California. 401
— introduced by .\. C. Lawson 401

Keyes, Charees : A measure of arid

erosion 404

— ; Corrasive efficiency of natural sand-

blast 63

: I'\ilse fault-scarps of des<'rt ranges. 65

Kieaiea. a drop-fault ci-ater: G. C.

Curtis 77

— . Presence of water in the unaltered

lava gases of 375

KixPEitiinoKiAX age of the Chattanoo-

gan .series ; E. O. T'lrich 96, 155

Ki.xDLE, VI. M.. Discussion of Il.-imilton

group of western .New York by... 113

KiiiK. C. T. ; Certain structural features

in the coal fields of New Mexico.. 405
-introduced by C. K. Leith 405

KiitKi'ATRicK, R., cited on morphology

of Mrilia ■ 364

Kiifi'XA, Sweden. Origin of the Iron

oi'es at 99

Kxiijirr. ('. \V.. and W. G. Mu.t.ER ; Re-
vision (»f pre-Cambrian classifica-
tion in Ontario 87

IvxoiM', AuoErii : Platinum-gold lode de-
posit in southern Nevada 85

Kvowi^Tox, !•". H. : Comparison of the
Cretaceous flnras of California with
those of other Cretaceous ni'eas... 414

— : Correlation of tlie Miocene floras of

western Inited States with those

of other Miocene areas 416

IvoiiTEVAi formation. Age of 3.S8

— invertebrate fauna 345

494

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Page
KooTENAY Valley, British Columbia,
New species of Ficus from the in-

terglacial deposits of the 159

Krafla volcano, Iceland 258

KuNZ, Geohge Frederick ; John Boyd
Thacher Park : The Helderberg es-
carpment as a geological park. . . . 110
- — , Memorial of Albert Smith Bickmore

by IS

Lake Algonquin, Battlefield and Fort

Brady beaches of 69

— Erie region, Crustal movements in.. 66

— Lahontan, Origin of the tufas of... 392
L.\ND model, the "last word in geology,"

Naturalistic ; G. C. Curtis 79

Laxe, a. C. : Can U-shaped valleys be

produced by removal of talus V. ... 75
Lang, W. D., of the British Museum,

cited on Merita normani Kirkpat-

rick 364

Laplace cited on isostasy 173

Laplace's functions and the figure of

the earth, Reference to 178

— memoir on the figure of the earth,

Summar.v of his mathematical anal-
ysis quoted from 173

Las.sbx Peak, California. Recent erup-
tions of : J. S. Diller 105

— — eruptions of May 20-22, 1915,

Characteristics of the ; R. S. Hol-
way and .T. S. Diller 397

Lava.s and sedimentaries of Kittitas
County, Washington, Relation be-
tween the Tertiary 137

Lawsox, a. C, Acting Chairman Sum-
mer Meeting, Session August 4,
1915 393

— , Discussion of colloidal migration in

ore deposits by 394

physiographic control in the

Philippines by 396

progressive change in mineral

composition of copper ores by 395

the term "bajada" by 891

^ Tertiary rocks of Oahu by. . . . 134

sedimentaries and lavas b.v. 137

— elected temporary Chairman of Cor-

dilleran Section 130

— ; Epigene profiles of the desert 391

— , Excursions of California Meeting of
1915 conducted wholly and in i)art

by 407. 417

— , Faulting in the Great Basin dis-
cussed by 139

— , H. O. Wood introduced by 404

— , .1. P. Bulwada introduced by 403

— , Questions on the Pleistocene of west-
ern Washington raised bv 131

— , W. S. W. Kew introduced l>y 401

Le Conte, .Joseph, Bibliography of . . . . 54

— , Memorial of 47

— , Photograph of 47

Lb Coxte Geological Club. Annual din-
ner of the Cordilleran Section in
conjunction with the Paleontolog-
ical and Seismological Societies,
held nnder the auspices of 138

— Memoi'ial Lodge in the Yosemite Val-

ley, Photograph of 48

Lee, W. T., cited on the undulating
character of Red Beds in northern

New Mexico 319

— - ; Reasons for regarding the Morrison
an introductory Cretaceous forma-
tion 303-314

— - ; Relation of Cretaceous formations
to the Rocky Mountains in Colorado
and New Mexico 114, 156

Page
Lee, W. T. ; The Morrison ; an initial

Cretaceous formation.. 90,151,303-314
LE(iEXDRE-'s law of density. Citation of. 173
Leidy, J., cited on the genus Notharv-

tii8 founded by 419

Leitii, C. K.. C. T. Kirk introduced by. 405
Lemlr \otharetiis (Eocene), Relation-
ship to the Adapidse and to other

primates of the 419

Lemuroidea, a classification of 432

— .Observations on Adapida; and other. 153
— , On the basicranial region of the. . . . 426

classification and phylogenv of

the ; W. K. Gregory 426

LEiMUR.s, The Indrisine or Indrisidiie. . . 440
Leverett, F., cited on so-called lowan
glaciation contemporaneous with
Illinoisan ins

— cited on the Illinois glacial lobe. ... 70
Lewis,..T. v., Discussion of Acadian Tri-

assic by 94

Libyan desert, Observations on sand-
blast made in ; W. H. Hobbs 396

.Origin of the basins within (he

hamada of the 396

Life members. Total of 8

Limestone of Vancouver Island, Sutton 82

— quarry, Fairmont, Illinois 70

Lincoln formation in Washington,

Stratigraphic and faunal relations

of the 169

LiNDGREX, Waldemar, Abstract of ad-
dress of retiring President G. F.
Becker read by 80

— , Chairman of meeting December 30,

First Vice-President 87

— , ^Meeting of December 29 called to

order by First Vice-President 5

— , Remarks on natural gas at Cleve-
land, Ohio, by 103

revision of pre-Cambrian classi-
fication in Ontario by 88

— spoke at annual dinner 104

LiXD, S. C, and C. F. Wiiittimore

cited on behavior of certain radio-
active minerals 195

LiTiiopiivs.-E and surface markings,

Iceland 255

Liip.KCK, A. K. ; Block diagrams of State

physiography 77

— introduced l)y E. O. Hovey 77

LOGAX, Sir W. E., cited on undulations

of Paleozoic rocks, Canadian side

Saint Lawrence River 287

LoGAX. W. N., quoted on correlation of

Morrison with Wealden fauna 344

LoLDERBACK. G. D. ; Basln Range fault-
ing in the northwestern part of the

Great Basin 138

— , Discussion of geologic structure in

western Washington by 136

petrologic nomenclature by. . . . 135

Tertiary rocks of Oahu by.... 134

— , Secretary of Cordilleran Section. . . . 129

— - ; Structural features of the Tsin Ling

Shan 405

Lkwir Pliocene of California. Correla-
tion of the ; Ralph Arnold 415

Lull, R. S. ; Correlation between the
terrestrial Triassic forms of west-
ern North America and Europe. . . . 413
— , Discussion of Sauropod dinosaurs b.y 153

— quoted on the reptiles of the Arun-

del formation . 337

— ; Sauropoda and Stegosauria of the
Morrison compared with those of
South America, England, and east-
ern Africa 90, 151, 323-334

LuRAY, Virginia. Specimen of stalactite,
with markings in U. S. National
Museum, from 281

INDEX TO VOLUME 26

495

Page

McAltee, W. L., cited on seeds found
in tiie peaty matter of the Scar-
boro beds 247

McGregor, J. H. ; Restoration of Pitlie-
canthropus and IMltdown and Nean-
dci'tlial man 140

Mackinac Island and their relations to
lake history, Old shorelines of ;
Frank B. Taylor 6S

McKiTTRiCK oil field. Geology of a por-
tion of the ; G. C. Gester 160

Macoux, • . cited on climate of Don

and Scarboro beds 247

Macrid.e, Involution of the Pacific

coast : E. L. Packard 170

AIaine, Klvidence of recent subsidence

on the coast of 01

Magmatic assimilation ; P. Bascom. ... 82

Malladra. a., cited on fumaroles of

Vesuvius 377

"repose" conditions of Vesuvius 370

Ma.m.maliax faunas (Miocene) of west-
ern United States : relation to those
of Europe and Asia 410

Ma.m.mai, remains in the asphalt beds of
McKittrick, California; N. C. Corn-
wall 107

MAMNtoTH tusks from I>ena River. Si-
beria. Study of ninety thousand
pounds of ; G. F. Kunz 407

Max. Geologic deposits in relation to

Pleistocene 100

— , Pithecanthropus and Piltdown and

Neanderthal 140

Mauiu.es of Alabama. Crvstalline 104

.Marixe Tertiary of California 16S

— vertebrates oif western North America

compared with those of other Trl-

assic areas : J. C. Merriam 413

Mar.sh. O. C. cited on Bothriospondy-

luH and Pleiirnrwhis 331

ODinion that European Wealden

was Upper Jurassic 3;?S

the ^lorrison dinosaurs 304

— , Ouotatioii from his "Dinosaurs of

Niirdi .America" ."..".1

Mar'I'ix. liurCE. Collection from the

T'mi)(ina formation TOO

M.VR'i'ix. .T. C.. Referencp to nrp-Cniii-

brian rocks mapped for the Canton

sheet 2SS

Mathews. E. B., Member of Aiiditing

Committee 11

— , S<>cnrilies of the Society examined

by 87

^Iattiikw. W. D. : Affinities of Ilyoii-

sudus 152

— cited on citniparative size of African

and American Saurouods 320

— ,i(,xv evidence of tlie relation-

sliip of the Notharcl idu' with the
.Xdiipidie. with the Uemui's, and
with dtliei' groiijis 421

- — .Discussion of -Adapidre and other
Lemnroidea and pliylogeny of the
higher primates by 153

fossil verlebrati' localities of

Florida by 154

paleontologic criteria in time

relations by 411

—on llie Kymposhuii "< 'Drrebitioii of

the Cretaceous" by 415

— : I'riiblem of correlation liv use of

^•er(ebiMt.-s 411

: l!econ>t niil ion of I be skeleton of
I'.raclilosaiirus 1.",'',

— : b'elallon of the Mioi'ene mammalian

faunas of westei'n United States to
tliose of Enrooe and Asia 41(!

— , Ifemarks on pisolites uf San An-

tonio. Te.xas, by 398

XXXVIII Bri.i,. GEi.r.. Sor. Am

Page
MATTHEW', W. D., Remarks on the Texas

Tertiary sands by 398

— , Report on vertebrates from the

Cold Springs horizon 470

— . Secretary section vertebrate paleon-
tology 151

— and C. DE LA Torre ; Megalocnus
and other Cuban ground-sloths.... 152

— and J. M. Clarke; Peccaries of the
Pleistocene of New York 150

Maury. Mtss . Reference to inter-
glacial bed near Cayuga Lake, New
York, described by 251

Medixa age. Shawangunk formation of. 150

Meek. F. B.. cited on Dakota fauna... 347

MEGAT.orxris and other Cuban eround-
slotbs : pRi-ios de la Torre and
W. D. Matthews 152

Melchfr. a. F.. cited on increase in
voi"mp of a column ^^ stratum of
rock throuffh crushing 186

Meairers-flect of the Paleontological

Society 147

ME^^oRTAT, of Albert Smith Bickmore :

Geo'-p-e Frederick K'inz 18

Aif'-ed Ernest Barlow: Frank D.

Adams 12

Horace Carter Hovev ; .Tohn M.

Clarke 21

.Tosenh r^e Conte ; Herman L.

F'lirchild 47

Ne^-ton Horace 'Winchell ; War-
ren TTpham 27

Mercat.lt. G.. cited on repose periods of

Vesuvius 376

MERRTAAr. .T. C . called to cbiiv of r'qii.
fornin AfpetinET of the F>aipnntolr>o-.
icRl Societv. session Aiitni«t 0. T^IS 416

— . Chairm.sn California Meetine of the
Pa'pontological Societv. August 3.
4. 101.5 410. 412

— : Comoarison of marine vertebra+es
of western North America with
those of other Triassic areas 413

— , Discission of naleontologic criteria

in time relations hv 411

f-eri'esti-ial Triassic forTn<? by... 41."^

Tertinrv rocks of Oabn bv 1 ?4

sedimentaries and lavas by. 137

Triassic faunas bv 412

on the symnosium "Correlation of

the Cretaceous" bv 41.5

— . Excursions of Paiifornia Meeting.

Ansrust 7-13. 1015. in cha'-'re of. . . . 417
— , Faultinii- in the Great Basin dis-
cussed bv 1 .^0

--. .T. C. .Tones introduced liy 302

— , Paner of F. TI. Knowlton on Miocene

floras read by 416

the comparison of Creta-
ceous floras of California with
those of othei- Cretaceous areas

read by 414

— ; Relation of the Tertiary eeolos-ica'
scale of the Great P.nsin to that of
Pacific Coast marsinal nrovince . . 136

- -, Report of jirranffements for the
meelinu of the I'aleontolotrlcal So-
ciety in California. August. 1015.
1>.v 147

- - : Review of the fauna of the Rattle-
snake Pliocene of eastern Oreron. . 160

- : Vertebrate fauna in the marine Ter-
tiary of California : their signifl-
canee in deieriniuinu' the aue of
California Teitiary formations.... 168
- faunas of the Pacific Coast reclon . 416

Mi:rrti,(,. G. p.. cited on evidence
acalnst meteoritlc origin of molda-

vltes 281

lunar crater forms 277

Vol.. 26. 1014

496

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Page
Merrill, G. P., cited on temperature
of meteorite on reacbing earth s

SUrf3.C6 • ^o4

■ — , Moldavite specimens from Boliemia

loaned by -gl

vs. Suess on moldavites ^oo

Meteorite, Temperature on reaching

earth's surface of a 284

Mesozoic and Tertiary rocks. Coast

ranges of California and Oregon.. Ill

Mexico, Correlation between inverte-
brate faunas of California and ;
E. L. Packard 414

MicHELSoN, A. A., cited on measuring

terrestrial tides 172

Migration and succession of human
types of the old Stone age of Eu-
rope ; H. F. Osborn 149

— in ore deposits. Role of colloidal .... 394
Miller, L. H. ; Some problems encoun-
tered in the study of fossil birds of

the west coast 417

Miller. W. G., and C. W. Knight ; Re-
vision of pre-Cambrian classifica-
tion in Ontario 87

Miller, W. J., Discussion of rift-moun-
tain by 90

— , Remarks on recent eruptions of Las-
sen Peak, California, by 105

Mineral deposits in unaltered Paleo-
zoic sediments, Organic origin of
some 85

Minerals (secondary) and etching phe-
nomena produced by hot circulating
solutions 275

Miocene and Oligocene faunas of Cali-
fornia. Review of the: P.. L. Clark. 416

— floras of western United States : cor-

relation with those of other Mio-
cene areas 416

— , Introductory remarks on correlation

of ; H. F. Osborn 415

— mammalian faunas of western United

States to those of Europe and Asia,
Relation of the; W. D. Matthew. . . 416

— of the Washington-Oregon province

and its relation to that of Califor-
nia and other Miocene areas ; C. L.
Weaver 416

Missouri, Devonian of central. . . . 112, 156

JIOHN, H.. cited on method devised for
gravity correction of the quicksil-
ver barometer 183

Moldavites, The 280

MoxTA>fA, Alberta Belly River beds
equivalent to .Judith Riv.er beds of
Dog Creek and Cow Island 149

— , Algal and bacterial deposits in the

Algonkian Mountains of 148

— , New facts bearing on the Paleozoic
stratigraphv of the region about
Three Forks 157

MoxTicuLirOROiDS. Morphology and his-
tology of the Trepostomata or. . . . 158,

349-374

Moodie, R. L. ; Scaled amphibia of the

Coal Measures 154

Mock, C. C., cited on 239 titles listed
in the bibliography of the Morrison
formation 299

— ; Geologic exposures of the Morrison. 151

— ; Origin and distribution of the Mor-
rison 90. 315-322

Morrison fauna and flora, List of in-
vestigators of the 300

— formation as determined by associ-
ated marine fauna, Time limits of
the 347

.Extension Into New Mexico of;

N. H. Darton 113

Page
Morrison (The) ; an initial Cretaceous

formation ; W. T. Lee. . 90, 151, 303-314

^ assigned to Lower Cretaceous.... 313

— ■ — , Character of 308

.Conclusions and references on... 313

. Distribution and thickness of . . . . 316

, Equivalent and associates of . . . . 307

formation. Criteria for determin-
ing the origin of the 317

, Faunal consideration of 304

.Geologic exposures of; C. C.

Mook 151

. List of species of animals and

plants named from 299

, Names formerly used for 315

, Origin and distribution of ; C, C.

Mook 90. 315-322

.Physical considerations of 305

.Physiographic conditions of 310

Sauropoda and Stegosauria com-
pared with those of South America,

England, and East Africa 90,

151, 323-334

. Structural relations of 309

.The invertebrate fauna of 90,

151, 343-348
Mountain, Tvne of rifted relict moun-
tain or rift 90

Mount Katahdin. Evidence of conti-
nental glaciation on ; G. C. Curtis. 78
Moureu. Charles, and A. Lepape cited
on helium of Carnot spring at Sau-

tenay (Cote-d'Or) 193

Multitueerculata. New evidence of

the aflSnities of; Walter Granger.. 152
Mvvatn, Iceland, The obsidian near. . . 285

Nagelfluh of Queljec and Salzburg. . . 60

Natural gas at Cleveland, Ohio ; F. R.

Van Horn 102

Neocene of California. Tentative cor-
relation table of the ; B. L. Clark . 167

Nevada, Platinum-gold lode deposit in

southern 85

Newberry, J. S.. quoted on Berea grit. 205

Newfoundland. Fossil alga^ of the Or-

dovician iron ores of Wabana 148

New Mexico and Colorado. Relation of
Cretaceous formations to the Rockv
Mountains in 114. 156

.Certain structural features in the

coal fields of 405

■ .Extension of Morrison formation

into : N. H. Darton 113

New York Academy of Sciences and the
insular government. Explorations
in Porto Rico supported by 113

. Fish fauna of the conodont bed

at Eighteen-mile Creek 154

.Hamilton grouo of western. 113.158

— • — .Peccaries of the Pleistocene of.. 150

. Post-Ordovician deformation in

the Saint Lawrence Vallev . 115, 287-294

Nomenclature. Plea for uniformity and
simplicity in petrologic ; G. M. But-
ler l.'?4

— .Report of Committee on Opological. 57

Norite. Dvroxenite. and pyrrotite from
Litchfield. Counecticut ; Ernest
Howe 83

North America. Close of .Jurassic and

opening of Cretaceous time in.... 29.")

North Aafertcax continent in Upper

Devonic time: A. W. Grabau S.S

Norton. W. H.. cited on glaciated rock
surfaces near Linn and near
Quarry, Iowa 70

Notharctus and Jyemuroidea. Bibliog-
raphy of 443

INDEX TO VOLUME 26

497

Page

NoTHARCTDS Eoccne lemur. Relation-
ship to the Adapidae and to other
primates of the 419

OahUj Tertiary rocks of 133

Obsidian analyses according to methods
of Cross, Iddings, Pirsson, and
Washington 262

— from Hrafntinnuhryggur, Iceland ; its

lithophysai and surface markings ;

F. E. Wright 255-286

O'CoNXELLj Maiuorie; a classification

of aqueous habitats 159

Officers, Correspondents, and Fellows

of the Geological Society, 1915.... 117

— • of the I'acitic Coast Section of the

Paleontologlcal Society 166

— raleontological Society 146

Ogdexsburg-Cantox quadrangle. Paleo-
zoic rocks of 287

Ohio Berea a non-marine formation... 210

— — sandstone in 96,155,205-216

— , Natural gas at Cleveland 102

— ; Olentangy shale and associated de-
posits of northern 95

— • of central 112, 156

Oil Held, Geology of a portion of the

McKittrick 169

— pools of southern Oklahoma and

northern Texas ; J. N. Gardner. . . . 102

— shales, iiegional alteration of; David

White 101

Oklahoma, Oil pools of southern 102

Olentangy shale and associated deposits

of northern Ohio; C. U. StaufiEer. . 95
of central Ohio and its strati-
graphic signiticance ; A. W. Gra-

bau 112, 156

Oligocene and iMiocene faunas of Cali-
fornia, Keview of the; B. L. Clark. 416
Ontario Bureau of Mines, Classilication
and nomenclature of pre-Cambrian

rocks adopted by 87

— , Canada, lievisiou of pre-Cambrlan

classilication in 87

OoLiTE.s, Theory of production of 58

OiJUOViciAN ir(jn ores of Wabana, New-

fouudlaud. r'ossil alga' of the 148

Ore alterations, Relation of physio-
graphic changes to; \V. W. Atwood. 106

— enrichment, Some chemical factors

affecting secondary sulphide 393

Oregon Bureau of Mines and Geology ;

I. A. Williams 137

— , Fauna of the Siphonalia Sutterensis

zone in the Koseburg quadrangle.. 169
— , Itcview of the fauna of the Rattle-
snake Pliocene of eastern 169

Organic origin of .some mineral deposits
in unaltered Paleozoic sediments ;

G. Van 1 ngen 85

Origin of dolomites; F. M. Van Tuyl.. 62

gypsum deposits, Hypothesis for.. 223

Monks Mound; A. K. Crook 74

— — the basins within the hamada of

the Libyan di-surt ; W. II. llobbs.. 396

Itocky Mountain phosphate de-
posits ; Eliot Blackwelder 100

iron ores of Kiruna, Sweden;

R. A. Daly 99

tufas of Lake Lahontan ; J. C.

Jones 392

thick salt and gypsum deposits;

E. B. Branson 103, 231-242

Ore deposits, Itole of colloidal migra-
tion in 394

OsBORN, II. F. ; Close of .lurasslc and
opening of Cretaceous time in North
America 295-302

Page

OsBORN, H. F., Discussion of Adapldffi
and other Lemuroidea and phylo-
geny of the higher primates by ... . 153

— ■ fossil vertebrate localities of

Florida by 154

■ — paleontologic criteria in time

relations by 411

■ — Sauropod dinosaurs by 158

the affinities of the Multituber-

culata by 152

— ■ — on the symposium "Correlation of

the Cretaceous" by 415

— , Introduction to symposium on the
passage from the Jurassic to the
Cretaceous by 151

— - ; Migration and succession of human
types of the old Stone age of Eu-
rope 149

— ■, Paleontologlcal Society called to

order by President 144

— ■ ; Recent work on the dinosaurs of the

Cretaceous 416

— , Resolution that a vote of thanks be
tendered by the members of the
California Meeting of the Paleonto-
logical Society by its Secretary to
the American Association for the
Advancement of Science, to the
President of the University of Cali-
fornia, and to the President of
Stanford University, in apprecia-
tion of courtesies extended to the
Society, offered by 417

— • ; The addition and evolution of "char-
acters" in paleontologic phyla 151

— , Section of vertebrate paleontology

called to order by President 151

— , Speaker at annual dinner 104

— , Session August 6, 1915, California
Meeting of the Paleontologlcal So-
ciety called to order by 415

Owen, Sir Richard, cited' on Bothrio-
spondylus from the Kimmeridgian
of England 331

Ozarks, Quaternary deformation of . . . . 67

Pacific Association of Scientific So-
cieties, Cordilleran Section met in
conjunction with 130

— Coast Macrida\ Evolution of the. . . . 170

— — , Relief of our ; J. S. Diller Ill

— — Section of the Paleontologlcal So-

ciety 145, 10(;

-, Stratlgraphie and faunal rela-
tions of the later Eocene of the. . . 108

Packard, E. L. ; Cretaceous faunas of

the Santa Ana Mountains 10!)

— ; Correlation between invertebrate
faunas of California and those of
Mexico 414

— • ; Evolution of the Pacific Coast

Macridw ITd

I'AiGE, Sidney, Discussion of papers

bearing on ore deposition by 40.".

— • the term "bajada" by 391

Paleobotaxic evidence of the age of the

Morrison formation; E. W. Berry.

90, 151, 33.".

Paleograi'hy, Correlation and chronol-
ogy on the basis of ; Charles Schu-
chert 411

Paleontological Society, Members de-
ceased 105

, Members-elect 165

, Ollicers, Correspondents, and

l\Iembors. 1915, of the 161

--. I'rocoedings of 141-170

-. Register of the Philadelphia
-Meeting, 1914 160

498

BULLETIN OP THE GEOLOGICAL SOCIETY OF AMERICA

Page
r'ALEOXTtn^OGic criteria used iu deter-
mining time relations, General con-
sideration of 410

— pliyla, The addition and evolution of

"characters" in; H. F. Osborne... 151
I'ALEONTOLOGY Of man, Discussion on

chapter of 147

Paleozoic corals. Evolution of the
anthozoa and the systematic posi-
tion of 157

— sediments. Organic origin of some

mineral deposits in unaltered 85

■ — stratigraphy of the region about
Three Forks, Montana; W. I'.
Haynes 157

Pattox, H. B., Chairman of Session

Decemlier 31, 1914 105

Third Section 99

— , First Section called to order V)y

Vice-I'resident Gl

— , Hyrum Schneider introduced by. . . . 398

— ; Occurrence of flow-breccias in Colo-
rado 399

— , I'hysiographic features of bolsons

discussed by 393

— ; Primary chalcocite in the fluorspar
veins of .Jefferson County. Colo-
rado 84

— ; Recent remarkable gold "strike" at
the Cresson mine. Cripple Creek,
Colorado 84

— , Remarks on recent eruptions of

Lassen Peak, California, by 105

the Coal Creek batholith by. . . 399

Peccaries of the Pleistocene of New
York ; J. M. Clarke and W. D.
Matthew 150

I'enxsylvaxia Piedmont, Pre-Cambrian

igneous rocks of the 81

Periodic table of Mendeleef cited on

atomic weights of the elements... 190

Perret, F. a., cited on condition of

Stromboli, 1914 387

"repose" conditions of Vesu-
vius 37<3

I'etrib, W. i\I. F., Reference to abrasion

by wind-driven sands 64

Petrologic nomenclature. Plea for uni-
formity and simi^licitv in ; G. M.
Butler 134

— problems of the Pacific area. Topic

B. Summer fleeting in California,
1915 '. 390

Philadelphia, Pennsylvania, Twenty-
seventh Annual Meeting of the
Geological Society of America. De-
cember 29, 30, and 31, 1914, held
at 1-128

PiiiLiiTixEs, i'hysiographic control in

the 395

Phosphate deposits, Origin of the

Rocky Mountain 100

Photographs, Report of Committee on. 57

PHiLOGEXY of the higher primates. Ob-
servations on the; W. K. Gregory. 153

Lemuroidea, On the classifica-
tion and ; W. K. Gregory 426

Pyrrhotite, norite, and pyroxenite
from Litchfield, Connecticut ; Ernest
Howe 83

Physiographic control in the Philip-
pines ; W. D. Smith 395

— features of bolsons. Some : H. E.

Gregory 392

• — • — • — western Europe as a factor in

the war ; D. W. .Johnson 11(»

— studies of the driftless area ; A. C.

Trowbridge 70

— study of the Cretaceous-Eocene pe-

riod in the Rocky Mountain front

I'age
and Great Plains provinces ; G. H.
Ashley 105

PiivsiOGRAPHY, Block diagrams of

State ; A. Iv. Lobeck 77

Pic d^Aurore Section; .J. M. Clarke... 150

I'ierce County coal field of Washing-
ton, Structure of ; .Joseph Daniels. . 132

I*iRSSOX, Jj. v.. Discussion of origin of

thick salt and gypsum deposits by. 103

Pisolites at San Antonio, Texas ;

Alexander Deussen 398

I'lTHECAXTHRorus and Piltdown and
Neandertal man. Restoration of ;
J. H. McGregor 149

PiUTTij A., cited on minerals not radio-
active 193

Platixum-gold lode deposit in southern

Nevada ; Adolph Ivnopf 85

Pleistocbxe, Asphalt formation not

later than Lower 167

— climatic oscillations, Graphic pro.iec-

tion of ; C. A. lieeds 106

— man. Geologic deposits in relation

to; C. A. Reeds 109

— of New York, Peccaries of 150

western Washington; ,J. H. Bi-etz. 131

I'LioCE.VE of eastern Oregon, Review of

the fauna of the Rattlesnake 169

I'OOLE, H. H., cited on the conductivity

of the earth's crust 190

Porto Rico, Geological reconnaissance

of 113. 150

I'ost-Ordovician deformation in the

Saint Lawrence Valley, New York ;

<;. II. Chadwick 115, 287-294

PoTO.MAC group. Age of the 336

— invertebrate fauna 345

"Potsda.m" and "calciferous" forma-
tions no more recognized 288

I'ottsville in Ohio unconformity com-
pared with Berea 213

I'owERS, Sidney ; Acadian Triassic 93

— , Basic rocks of Rhode Island dis-
cussed by. 92

— ; Geological history of the Bay of

Fundv 94

— introduced by R. A. Daly 9.3, 94

Pratt, .T. IL, cited on attraction of the

Himalayan range 178

Pre-Ca.mhriax classification in Ontario,
Revision of ; W. G. Miller and C.
W. Knight 87

— igneous rocks of the Pennsylvania

I'iedmont ; F. Bascom 81

— rocks of Ogdensburg-Canton quad-

rangles 287

Precipitatio.v, Relation of run-off to. . 22;i

Predentate dinosaurs. Species found of. 329

Pre-Pleistocexe geologv in the vicinity

of Seattle ; C' B. Weaver 130

I'residextial address of G. F. Becker.

86, 171-204

Pressure on rocks and minerals, Some

effects of ; John .Johnston 83

Prlmates, Observations on the phy-

logeny of the higher 15."1

Prohle.m of correlation bv use of verte-
brates : W. D. Matthew 411

the Texas Tertiary sands ; E. T.

Dumble 447

Proceedixgs of the Fifth Annual Meet-
ing of the Pacific Coast Section of
the Paleontological Society ; C. A.
Waring. Secretary 166

Fifteenth Annual Meeting of

the Cordilleran Section of the Geo-
logical Society of America, held at
Seattle. Washington. Mav 21 and
22, 1914 ; G. D. Louderback. Secre-
tary 129-140

INDEX TO Yt)LUME 26

499

11?.

SI)

1:..-. __

Page

Proceedings of the Sixth Annual Meet-
ing of the Paleontological Society,
held at Philarlelphia, I'ennsylvania,
December liO, 80. and 31. 1914 ;
R. S. Basslfi-. Secretary 141-170

Summei- .Meeting of the (leolog-

ical Society of America, held at the
I'niversity' of California and at
Stanford ' I'niver.sity. August .'!. 4,
and .',. 101.1: .1. A. Taff. Secretary
l>ro tail X,SO-40S

Paleontological So-
ciety, held at the Pniversity of
CaMfornia and at Stanford Pui-
versitv. August 3. 4, .5. and (>.
1'.>1.". :' Chester Stock. Secretary pro
tan 409-41.S

Twenty-seventh Annual Meet-
ing of the ecological Society of
America. held at Philadelphia,
Pennsvlvania. December 20. :'A), and
."1. lo'll : E. O. Hovey. Secretary, l-l'.!

I'uossER. CiiAUi.K.s. Discussion of classi-
fication acpieous habitats by I-)'"'

Pkosseu. C. S.. cited on P.erea-P.edford
contact at Warner Hollow, Ash-
tabula County, Ohio ^14

Cussewag sandstone ^li>

— , Discussion of Hamilton group of
western New York by

North American continent in

Upper Devonic time by

— , T'nconformity at the base of the
Berea sandstone in Ohio discussed
bv '•><■'■

PuoiTY. W. F. : Crvstalline marbles ot

Alabama ll^'-^

PfRdATOiRK formation. Perry and llaug

cited on •'•"'

I'yuoxENiTE^ pyrrhotite, and norite
from Litchtield. Connecticut : Ernest
Howe ^■'

QUATKR.VAUV deformation in southern
Hllnois and southeastern Missouri :
E. W. Shaw 67

li.vuin.vcTiMTv and isostasy ; G. _}'• ^^,
P.ecker 86, 1^^1-204

U.VDKJLOGY, Recent advances in lo'J

Rattlesnake Pliocene of eastern Ore-
gon. Review of the fauna of the... 169

Rav, .T. C. : IO.\ami)les of successive re-
l)laceinent of earliei- sulphide min-
erals bv later sulphides at P.utte,
.Montana 402

— introduced bv C. F. Tolman, .7r 402

Raymond. P. 10.. Discussion of Paleozoic

stratigi-aphv about Three Forks,

Montana, by 157

Red P.ed gyi)snm deposits of western

Wyoming. Conditions of the upper. 222

— Reds (Chugwater fcii-niati<jn ) of west-

ern Wyoming. Description of 218

of western Wyoming. Origin of;

E. R. Branson 01, 217-230

Reeds, C. A. ; fJeologiir deposits iti rela-
tion to Pleistocene man 109

— ; (iraphlc projection of Pleistocene

climatic oscillations 106

Registek of the Califoi'nia Meeting.

1915 4().S

meeting of the raleunioldgical

Society at I-biladelpliia. 1914 PiO

I'iiiladelpbia .Meeting, 1914.... 11.".

Seattle Meeting of the Cordil-

leran Section 140

Reid. H. F.. Renuirks on crustiil move-
ments In Pake ICrle region by 07

Page
Reid, II. F.. Remarks on glacial ero-
sion by '73

Report of Auditing Committee 87

of Paleontological Society . . 150

Committee on Geological Nomen-
clature 57

Council of Paleontological Society. 144

Editor 10

I'hotograph Committee 57

the « ouncil 5, 87

Rhode Island, Basic rocks of 92

Richards. T. W.. and M. E. La.mbert
cited on comparative atomic weight

determinations of lead 192

Rich. .T. L.. Discussion of evidence of
recent subsidence on the coast of

Maine by 91

— . Monks Mound discussed by 75

— ; Some peculiarities of glacial erosion
near the margin of the continental

glacier in central Illinois 70

RiiT-MotNTAiN. Type of rifted relict

mountain, or ; .1. M. Clarke 90

ItiGGS, E. S.. cited on Bnichiusauvas . . . 329
deltas in the Morrison forma-
tion 320

• largest known dinosaur 153

origin of Morrison formation.. 318

RiVEU beds. Alberta Belly, and Montana
.Tudith, of Dog Creek and Cow

Island, efjuivaleut to 149

River waters. Materials in solution in. 224
Rocks of northeastern Illinois and east-
ern Wisconsin, .\lexandrian . . . 95, 155

- Rhode Island, Basic 92

Rocky Mountain front and (Jreat I'lains
provinces. Physiographic study of
the Cretaceous-Eocene period in the. 105
. phosphate deposits. Origin of the. 100

— Mountains in Colorado and Now Mex-

ico. Relation of Cretaceous forma-
tions to the 114. 156

Rodents of Rancho La Brea ; L. R.

Dice 167

Rogers. A. F.. Discussion of papers

bearing on ore deposition by 403

— introduced by C. F. 'J'olman. Jr 395

— ; Sericite. a low temperature hydro-
thermal mineral 395

Rose, Gcstav, .Analysis of the litho-
phvsa' from Cerro de las Navajas
by" 259

RosEiu'RG (|uadrangle. Oregon, Slphnn-

uiiii xiiitcrai.sis zone. Fauna of thi-. 109

RuCK.MAN, .1. II. ; Fauna and relations
of the white shales of the Coalinga
district 108

— ; Relations of the Santa Margarita
formation in the Coalinga east
side field 160

RrTiiERi'oRD, Sir Ernest, cited on

structure of atoms 190

Saint Lawrence Valley, New York,
I'ost-Ordovician deformation in the.

115. 287-294

Sai.ton Sea. Interesting changes in the

composition of the; A. E. Vinson.. 402

Saxd-I!I.as T. Corrasive efficiency of nat-
ural ; Charles Keyes 03

— erosion from studies in the Libyan
desert. Range and rhythmic action
of : William II. llobbs 03

Sands, I'roblem of the Texas Tertiary. 447

Sands I'oSE. ICxtent of Berea 209

in ( >hio, Berea 90. 1.55, 2O.-.-210

S a n t a a n a Mountains, Cretaceous

faunas of the 109

Santa Catai.ina Mountains, Arizona,

Bajadas of the 391

500

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Page

Savta Margarita formation in tlie Coa-
linga east side field. Relations of
the ; J. H. Ruckman 166

Santa Ynez River district, Santa Bar-
bara Countv, California, Geology of
a portion of the ; W. S. W. Kew. . . 401

Sarle, C. J., Discussion of classification

of aqueous habitats by 158

_ Shawangunli formation of Me-
dina age by 150

Saunders, E. .T. ; Relation between the
Tertiary sedimentaries and lavas in
Kittitas County, Washington 137

Sauropoda and Stegosauria, Geographic

and geologic distribution of 326

• — of Europe 332

the Morrison compared with

those of South America. England,
and eastern Africa; R. S. Lull. . . . 00.

151. 323-334

— of the Morrison, 300 titles on the. . . 29!)
Sauropod dinosaurs. Heads and tails ;

a few notes relating to 153

Savage, T. E. ; Alexandrian rocks of
northeastern Illinois and eastern
Wisconsin 95, 155

— , Devonian of central Missouri dis-
cussed by 112

Szab6, S., and Roth, , cited on the

lithophysse 256

Scaled amphibia of the Coal Measures ;

R. L. Moodie 154

Scherzer, W. H.. cited on ice work in

southeastern Michigan 70

Schiller, F. C. S., cited on radioactive

transformations 194

Schneider, Hyrum ; Geologic age of the
Coal Creek batholith and its bear-
ing on some other features of the
geology of the Colorado Front
range 398

— introduced by H. B. Patton 398

Sciiuchert, Charles ; Correlation and

chronology on the basis of paleog-
raphy 411

— , Devonian of central Missouri dis-
cussed by 112

— . "Diastrophic action is at the basis

of chronogenesls," Quotation from. 306

— , Discussion of algal and bacterial de-
posits in the Algonkian Mountains
of Montana by 1 48

classification of aqueous hab-
itats by 158

geological reconnaissance in

Porto Rico by 114

paleontologic criteria in time

relations by 411

Paleozoic stratigraphy about

Three Forks, Montana, by 157

Triassic faunas by 412

on the symposium "Correlation

of the Cretaceous" by 414

— . Paper of R. S. Lull on "Terrestrial

Triassic forms" read by 413

— quoted in a review of Hennig's work

"Am Tendaguru" 328

on the marine Triassic of Cali-
fornia. Oregon. Nevada. Idaho, and
eastern Wyoming '. 218

— ; Shawangunk formation of Medina

age 150

Schuchert's map of the Salina Sea.

Reference to 238

Scott. W. B.. cited on the horizons of

the Morrison 300

ScuDDER, , quoted on fossil beetles

from the Scarboro beds 247

Sculpturing of rock by wind in the
Colorado Plateau province ; H. B.
Gregory 393

Page

Seattle, Washington, Meeting of the
Cordilleran Section of the Geolog-
ical Society in conjunction with the
Pacific Association of Scientific So-
cieties at 130

, Pre-Pleistocene geology in the vi-
cinity of 130

Secretary 's Report 5

of the Paleontological Society... 144

Section, Group B, Second 95, 154

— . Third 99

Sedimentaries and lavas in Kittitas
County, Washington, Relation be-
tween the Tertiary 137

Sedimentation in diastrophism and vul-

canism. Role of; F. M. Handy.... 138

Sediments, Unaltered Paleozoic 85

Seeley, H. M.. cited on specimen of
Stegosauria in Woodwardian Mu-
seum, Cambridge 332

Sellakds, E. H. ; Correlation between
the middle and late Tertiary of the
South Atlantic coast of the United
States with that of Pacific coast. . 410

— ; Stratigraphic relations of the fossil

vertebrate localities of Florida.... 154
Skkicite. a low temperature hydrother-

mal mineral ; A. F. Rogers 395

Shale and associated deposits of north-
ern Ohio. Olentangy 95

— . Bedford and Cleveland, Ohio 209

— of central Ohio, Olentangy 112, 156

Shales, Regional alteration of oil 101

Shawangunk formation of Medina age ;

Charles Schuchert 150

Shaw, E. W. ; Quaternary deformation
in southern Illinois and southeast-
ern Missouri 67

Siberia. Mammoth tusks from Lena

River 4.07

Sierra de los Caballos, Reference to

fault-scarps of 65

Sierra Nevad.4^, Structure of the south-
ern ; J. P. Bulwada 403

SiPHOXALiA siitterensis zone in the
Roseburg quadrangle, Oregon,
Fauna of the 169

Sloths, Megalocnus and other Cuban

ground- 152

S.MiTii, Burnett, Discussion of fish
fauna of Eighteen-mile Creek, New
York, by 154

Smith, .T. P.. California Meeting of the
Paleontological Society. Session Au-
gust 4. 1915, called to order by. . . 412

— , Discussion of paleontologic criteria

in time relations by 411

Triassic deposits of .Japan bv . . 413

on the symposium "Correlation

of the Cretaceous" by 414

— ; Relations of the invertebrate faunas

of the American Triassic to those

of Asia and Europe 412

— , Terrestrial Triassic forms discussed

by 413

Smith, W. D. ; Physiographic control

in the Philippines 395

Smoker in honor of the Geological So-
ciety of America and the Paleonto-
logical Society by local members of
former organization 86

Soddy, F.. cited on "isotopes" and radio-
elements 191

Spencer, , cited on interglacial

wood 251

Si'herulites and lithophysfe 262

Spcrr, .1. E.. Reference to statement on

fault-planes 65

Stanford University Meeting of the Pa-
cific Coast Section of the Paleon-
tological Society, Papers of the... 166

INDEX TO von: ME 26

501

Page

Stanp'ORD University. Summer Meeting
of ttie Geological Society of Amer-
ica, 1915, held at 389

Stanley-Browx, JosErii. Keport of

Editor 10, 11

Stantox, T. W., oiled on molluscan
faunule from tlic Cretaceous of
Montana 345

— ^ ; Correlation between the Cretaceous
of the Pacific area and that of
other regions of llie world 414

-of the Cretaceous invertebrate

faunas of California 414

• — , Discussion of palcontologlc criteria

in time relations by 411

— , Session August 5, 1915. of the Cali-
fornia Meeting- of the Paleonto-
logical Society called to order by. . 413

• — ; The invertebrate fauna of the Mor-
rison formation 90, 151, 343-348

Stauffer. C. R. : Olentangy shale and
associated deposits of northern
Ohio 95

StegosaupvIA and Sauropoda of the

Morrison 90, 151, 323-334

Stephenson', L. W. ; Cretaceous-Eocene
contact in the Atlantic and Gulf
Coastal Plain 168

Steunuerg. C. I-I. : Evidence proving
that the Belly River beds of Al-
berta are equivalent to the .Tudith
River beds of Dog Creek and Cow
Island, Montana 149

Stoke.s, • , cited on relation between

gravitv and latitude discovered b.y
Clairaut

174
149

Sto.xe age of Europe, Migration and suc-
cession of human types of the old.

STifATrGitAPHic (A) disturbance through
the Ohio Valley, running from the
Appalachian Plateau in Pennsylva-
nia to the Ozark Mountains in Mis-
souri : .Tames II. Gardner 60, 477

— and faunal relations of the later Eo-

cene of the Pacific coast ; Harold
Hannibal 168

• Lincoln formation in

Washington ; C. E. Weaver 169

■ — relations of the fossil vertebrate lo-
calities of Florida; E. H. Sellards. 154

SritATiGUAriiv of the region about
'I'hree Forks. Montana. New facts
bearing on the Paleozoic : W. I'.
Haynes 157

— -. Upper Cretaceous 149

Stuomp.oli volcano, Italy 387

SircicriitAr. features of the Tsin Ling

Shan ; G. D. Louderback 405

S'rRUCTr;RE of the southern Sierra Ne-
, vada ; .T. P. P.ulwada 403

Sriii'TT, R. .7., cited on lielium 190

— and .ToiiANX Koi:.\igsiu:i!Ger cited on

e(|uatioii of eartli's radiation 197

SwKDKV, Origin of the iron ores at

Kiruna 99

Siii!siriE.N'CE on the coast of Maine, Evi-
dence of recent ; C. A. Davis 91

ScDAN, Observations on sand-blast made
in the Anglo-Egyptian ; W. H.
Hobbs 396

SrK.ss, F. E., cited on markings found

on tlie moldavlles of P.olieuiia 277

moldavites as of nieteoritic ori-
gin 281

Sri.i'MiDE minerals at Butte. Montana:
examples of successive replacement
of earlier by later sulphides ; .7. C.
Ray 402

— ■ ore enrichment. Some chemical fac-
tors affecting secondary ; S. W.
Young 393

Page

Summer Meeting in California, 1915,

Topics for discussion at 390

Sux, Uranium and the 194

Sr.N'DAXCE invertebrata fauna 347

SuTTOx limestone of Vancoviver Island. 82
SvExiTE fakerite) of the middle and
northern Blue Ridge region. Vir-
ginia. Hypersthene ; T. L. Watson

and .7. H. Cline 82

Symposium on the passage from the Ju-
rassic to the Cretaceous. .7oint ses-
sion with the Paleontological So-
ciety for the 90, 151

Taff. .7. A.. Acting Secretary Summer

Meeting. Session August 5. 1915... .S9r>
— . Alexander Deussen introduced by. . . 308
— , Secretar.v Summer Meeting. Session

Auffust 4. 1915 393

— and F. C. Calkixs, Excursion of Cal-

ifornia Meeting. August 10. 1915.

in charge of 408

Talu.s? Can U-shaped valleys be pro-
duced b.v removal of 75

Tarr. R. S.. cited on glaciation of the

Mount Katahdin region 7'~i

Taylor. F. B.. Discussion of crustal

movements in T^ake Erie region by. i;7

glacier erosion by 73

— ; Old shorelines of Mackinac Island

and their relations to lake histoi-y. 08

'J'ayt.or. W. p. : History of the Aplo-

dontia group 417

Te.iox-Rocexe. lone formation of the
Sierra Nevada foothills, a local
facies of the Upper 168

Ti;xr>AGT^RrT district of German East

Africa 32S

Terrestrial Triassic forms. Correlation
between western North America
and Europe ; R. S. Lull 413

Tertiary formations in California 108

western Washington. Correla-
tion of the 170

— geolos-ical scale of the Great Basin

to that of the Pacific Coast mar-
ginal province. Relation of the: .7.

C. Merriam 130

- — (piiddle and late> of the south At-
lantic coast of the United States
.-ind that of the Pacific coast. Cor-
relation between: E. II. Sellards... 41(1

— - sedimentaries and lavas in Kittitas

Co\inty. Washington. Relation be-
tween the : E. .7. Saunders i;'.7

— .'cands. Problem of the Texas.. . . 398, 447

— reefs and reef coi-al« ^(\

— rocks of Oabu : C. H. Hitchcock. . . . 13.".
Ti:xAs (east). Descriptions of forma-
tions of 459

— . Oil pools of northern 102

— ^. Pisolites at San Antonio 398

Tertiarv sands. Problem of the : E.
T. Dumble 398, 447

'i'HAf"iiEF! Park. .7ohn Boyd 110

TiiAniKR. Mrs. Emma Tre.vowell.
Land for .7ohn Boyd Thacher Park
douated by 110

i'liiGK- salt and gvpsum deposits. Oricln

of 103, 231-242

TilllM) Section. <;roiiii C: Petrologic,

Mineralo'jic and l^couoniic 81

Tiio.MsoN, Sir .7. .7.. cited on sas analy-
sis and atomic weiiihl determina-
tions 191

I'liiiMsoN and Tait's Natural Phllos-
o')hv quoted on early conditions of
the earth 177

502

BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Page

Three Forks, Montana, New facts
bearing on the I'aleozoic stratigt-a-
phy of the region about l.")?

Titles and abstracts of pajiers pre-
sented in general session and dis-
cussions thereon ."i.S

TiTTMANN, O. H., cited on records of
geodetic surve.vs of northern Va\-
rope 1st

Toad from Rancho La Brea, Extinct ;

C. L. Camp 107

ToASTMASTER at annual dinner, E. O.

Hovey 104

ToLMAX, C. F., Jr., S. W. Young intro-
duced by S'.C.

— , A. E. Vinson introduced by 402

— , A. F. Uogers introduced by 3;(.")

— , .7. C. Kay introduced by 402

— ; Bajadas of the Santa Catalina

Mountains, Arizona 301

— , Chairman of the Cordillei-an Section,

Summer Meeting called to order by. :!i)0

Summer Meeting, Session August

5. 1915 ■ -.i'.Kj

■ — , Discussion of Ave types of wind

erosion by 302

papers bearing on ore deposi-
tion by 403

— ; Examples of progressive change in
the mineral composition of copper
ores 394

— , Paper of H. E. Gregory on bolsons

read by 392

wind sculpture of rock in

the Colorado Plateau province read

by 393

— , Remarks on physiographic control in

the Philippines by 390

the structure of the southern

Sierra Nevada by 404

— , Secondary sulphide ore enrichment

discussed by 394

T()Ki)\T<). Don and Scarboro l>eds at...

244-248

Torre. C. de la, and W. D. Matthews ;
Megalocnus and other Cuban
ground-sloths 1.52

Treasurer's report s

of the i'aleontological Society.... 145

Trei'ostomata, Authorities cited on the

morpholog.v of the .".50

— , Communication ])ores of 35(;

— .Function of Acanthopores of the,.. 3t>3

— , Intrazocecial spines of the 358

— morphology, Summary and conclu-

sions .'105

— or Monticuliporoids. I>i1)liograi)hy (if. :',t;i'>
, Studies of the morphology ;ind

histology of the ; J'L R. Cumings

and .1. .T. Galloway 158. 34!»-:;74

— , The cinpiihim of the 3(il

— , Wall structure of 358

Triassic, Acadian 9;',

— deposits of Japan ; H. Yabe 4]."i

— invertebrate faunas of America mikI

their relations to those of Asia
and Europe 41"

— marine vertebrates. Comparison of.. . 413
Trowi'.ridge. a. C. : Physiographic

studies in the driftless area 70

Tsi.v LixG Shax, Structural features of

the 405

Tufas of Lake Lahontan, Origin of the :

J. C. Jones 392

TuRXKR. H. W., Remarks on pisolites at

San Antonio, Texas, by 398

T^LRiCH, E. O., California Meeting of
the Paleontological Society called
to order by 410

Page
Llrk-h, E. O., cited on "infundibular

diaphragms" 351

morphology of Trepostomata. . . 350

— ; Criteria of correlation from the

point of view of the invertebrate

paleontologist 410

— .Discussion of Alexandrian rocks bv .

9.5, 155
algal and bacterial deposits in

the Algonkian Mountains of Mo!i-

tana b.v 148

Pateontologic criteria in tine

relations by 411

on the symposium "Correlation

of the Cretaceous" by 414

— , Hamilton group of western New

York discussed l>y 113

— : Kinderhookian age of the Chalta-

noosan series 96, 155

— quoted on diastruphic boundai-ies. . . . 310
UxivEUSiTY of California. Summer

fleeting of tlie Geological Society

of Americc). 1915, held at the . '. 3«o

— — ^Washington Meeting, Papers of.. 169
. Seattle. Washington. I-'ifteenth

Annual Meeting of the Cordilleran

Section at 130

T'PHAM. Warrex. Memorial of Newton

Horace Winchell by 27

Upper Cretaceous stratigraphy, I 'a per

by C. H. vSter"ber<? bearin'? on. . . . 149

— Devonic time, North American con-

tinent in 88

T'raxium and the sun 194

U-SHAPED valleys. Can Ihev l)e produced

by removal of Talus?: Alfred C.

Lane 75

VAX DEx Broek, A., cited on positive
electric charges in atomic weights
of the elements 190

A'.vv Horx', F. R.. Discussion of organic
oi'iffin of some mineral deposits in
unaltered Paleozoic sediments l).v.. 80

--: Natural gas at Cleveland. Ohio. .. 102

VAX TDse. C. R., spoke at annual <lin-

rer 104

\"A\ IxoEx, Gilbert. Discussion of •■••o-
logical reconnaissance in Porto Rico
by 114

— . I<"irst Section, flroup T*>. pi'esided o er

liy 95. 154

— ; Fossil algiP of tlie Ordovician iron

ores of Waliana. Newfoundland. . . . 148

— : ()iv.;anic origin of some deposits in

unaltei-ed Paleozoic sediments 85

\A\ 'I'lYL, F. M.. introduced bv Stuart

Weller 02

— : New points on the origin of dolo-
mites 02

VAUGHAX, T. W., Bacterial studies of
Great Salt Lake and sea water sug-

.gested b.v 58

— : Coral reefs and reef corals of the
southeastern United States, their
geological history and significance. 58

---. Fnna Futi lioring 60

---.Karl F. Kellei'man introduced by... 58
— -. Preciiiitation of calcium carbonate
and formation of oolites. Reference

to 58

Verbeek, R. D. ^I.. cited on moldavites

as of meteoritic origin 281

Vesuvius 376

Vertebrate fauna in the marine Ter-
tiary of California : their signifi-
cance in determining the age of
California Tertiary formations : J.
C. Merriam 16S

INDEX TO VOLUME 26

503

Page

V^ERTEBRATK faunas of the Pacific Coast

region ; J. C. Merriam 416

■ — localities of Florida. Stratigraphic

relations of the fossil I5 '

• — paleontology. Section of 151

VioRTior RATES (marine) of western
North America compared with

those of other Triassic areas 41:'.

— , Problem of correlation by use of . . . 411
VixsoN, A. E. ; Interesting changes in

the comnosition of the Salton Sea. 402

— introduced by C. F. Tolman, .Tr 402

Virginia. Hyocrsthene syenite (alserite)

of Blue Ridge region S2

Volcanoes, Age as the determinant of

character in ; G. C. Curtis < 8

— of sotithern Italy. Present condition

of the : H. S. Washington and A. T..

Day . 105. 375-388

Von Ri'ciithofen, ■ •, cited on hollow

spherulites in Hungarian rhyolites. 256
Vote of thanks to the Academy of Nat-

ural Sciences of Philadelphia 110

Vulcan ISM and diastrophism, Role of

sedimentation in 138

Volcano. Bergeat, Ponte and de Fiore

cited on solfataric activity of 3S4

— volcano, Italy 384

Wabana. Newfoundland. Fossil algse of

the Ordovician iron ores of 148

Walcott, C. D. : Occurrence of algal
and bacterial deposits in the Al-
gonkian Mountains of Montana... 148

— spoke at annual dinner 104

Ward, L. F.. cited on cycads SOO

— fossils from the Jurassic of

Wyoming 335

Wark diorite and Sutton limestone of

Vancouver Island. Canada 82

War. Physiographic features of western

Europe as a factor in the 110

Washington. Correlation of the Ter-

tiar.v formations in western 170

— . Eocene of the Cowlitz Valley 136

— Oregon province Miocene and its re-

lation to that of California and

other Miocene. areas ; C. T^. Weaver. 416

— , Geologic structure in western 135

— , Geology of portions of western 307

— •, Pleistocene of western 131

— , Pre-Pleistocene geology in the vi-

cinitv of Seattle 130

— , Relation between the Tertiarv sedi-

mentaries and lavas in Kittitas

Conntv 137

— . Stratigranhic and faunal relations

of the Tyincoln formation in 160

— , Structure of Pierce County coal field

of 132

WAsniNGTON, II. S.. cited on igneous

magmas and lava gases 376

— , Descent Into Vesuvius crater with

Dr. A. Malladra made by 378

— and A. Tj. Day; Present condition of

the volcanoes of southen Italy. . . 105.

375-3S,S

— and Day. Acknowledgment of

valuable assistance and courtesies
received from officials and profes-
sors while studying the volcanoes

of southern Italy 376

Washita invertebrate fauna ^4S
Watsov. T. T<.. Remarks on organic
origin of some mineral deposits In
una'torfd Paleozoic sediments bv . . 86
• — and .T. IT. rLiNi; : Ilvnersthene syen-
ite fakerlte) of the middle and
northern Blue Ridge region, Vir-
ginia 82

Paee
Weat.den formation. Age of 338

— invertebrate fauna 344

Welter. Stfart, F. M. Van Tuyl intro-
duced bv 62

Weaver. C. E. : Correlation of the Ter-
tiarv formations in western Wash-
inffton 170

— , Discussion of Tertiary sedimentaries

and lavas bv 137

— elected Councilor Cordilleran Sec-

tion 131

— : Eocene of the Cowlitz Vallev.

Washinston 136. 160

— . Faulting in the Great Basin dis-
cussed by 130

— ; Geologic structure in western Wash-
ington 135

— ; GeolojTv of portions of western

Washington 397

— : Miocene of the Washington-Oregon
nrovince and its relation to that of
California and other Miocene areas. 416

— : Pre-Pleistocene geology in the vi-
cinity of Seattle 130

— : Stratigranhic and faunal relations
of the Lincoln formation in Wash-
ington 169

White. C. A., cited on Bear River

fauna 34R

Dakota fauna 347

invertebrate fauna of the Mor-
rison 34.1

the origin of the Morrison for-
mation 318

White. Davtd. Discussion of Hamilton

group of western New York by.. . . 113

— : Regional alteration of oil shales.. . . 101
— . Fnconformitv at the base of the

Berea sandstone in Ohio discusspd

by 96. 155

White. I. C. Berea equivalent to Corry

sandstone of 210

— , Discussion of crustal movements in

Lake Erie region by 66

Hamilton group of western

New York by ll.*^.

White shales of the Coalinga district.

Fauna and relations of the 16.S

WiELAND. G. R.. Discussion of aliral and
bacterial deposits in the Algonkian
Mountains of Montana by 14s

fish fauna of Eighteen-mile

Creek. New York, by 154

Williams. I. A. ; Oregon Bureau of

:\Iines and Geology 137

Williams. M. Y., Discussion of classi-
fication of aqueous habitats by. . . . 15.S

Hamilton group of western

New York by 11:'.

Willis, Bailey. Discussion of paleon-

toiogic criteria In time relations b.v. 411

• • — epigene profiles of the desert

by 301

Williston, S. W.. cited on faunal rela-
tions of the Morrison 200

Wii,MOT, ARTiir-R B.. Death of 5

Winchell, Newton Horace, Blbllogra-

nhy of 31

— . Memorial of 27

— : Photogra jih of 27

Wind sculnturing of rock In the Colo-
rado Plateau province 393

WiNTRTNoriAM. .1. P.. DiscussloD of ef-
fects of px'essure on rocks and min-
erals by 84

Wisconsin-. Alexandrian rocks of east-
ern 9.T. 155

Wolff, .1. E.. Remarks on effects of

pressure on rocks and minerals. ... 84
.Statement of work on sulphides by. 30 1

XXXIX -Bull. Geol. Soc. Am., Vol. 26. 1014

504

lUJLLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA

Page
AA'ooD, H. O. ; A possible causal mecli-
anism for heave fault-slipping in
the California Coast Kange region. 404

— introduced by A. C. Lawson 404

WooDWAUD. A. S., cited on specimen of
Stegosauria in Woodwardian Mu-
seum. Cambridge 332

WoonwAHD. K. S., Remarks on natural

gas at Cleveland. Ohio, by 103

WuiiniT, <!. F.. cited on the Don and

Scarboro beds of Ontario 248

Wkight, F. E. ; Obsidian from Hrafn-
tinnuhryggur, Iceland : its litho-
physic and surface markings. . . 255-286

WiOMixG, Red Beds of western.

Page

Gl, 217-230

Yabe, H. ; Comparison of the Creta-
ceous faunas of Japan with those
of western United States 414

— ; Triassic deposits of Japan 413

Young, S. W.. introduced by C. F. Tol-

man, Jr 393

■ — ; Some chemical factors affecting sec-
ondary sulphide ore enrichment... 393

ZiRKEL

— , cited on Richthofen's hy-
pothesis of chemical alteration.... 256

THE GEOLOGICAL SOCIETY OF AMERICA

OFFICERS. 1915

, President :

Arthur P. Coleman, Toronto, Canada

Vice-Presiden ts :

L. V. PiRSSON, New Haven, Conn.
H. P. CusHiNG, Cleveland, Ohio
Edward 0. Ulrich, Washington, D. C.

Secretary:

Edmund Otis Hovey, American Museum of Natural History,

New York, N. Y.

Treasurer:
Wm. Bullock Clark, Johns Hopkins University, Baltimore, Md.

Editor:
J. Stanley-Brown, 26 Exchange Place, New York, N. Y.

Librarian:
F. E. Van Horn, Cleveland, Ohio

Councilors:
(Term expires 1915)
Whitman Cross, Washington, D. C.
WiLLET G. Miller, Toronto, Canada

(Term expires 1916) <..

R. A. F. Penrose, Jr., Philadelphia, Pa.
W. W. Atwood, Cambridge, Mass.

(Term expires 1917)

Charles K. Leitii, Madison, Wis.
Thomas L. Watson. Charlottesville, Va.

-vl

C.I

G
?

1
3e

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