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HARVARD UNIVERSITY.

LIBRARY

OF THE
MUSEUM OF COMPARATIVE ZOOLOGY.

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PROCEEDINGS

OF THE

California Academy of Sciences

THIRD SERIES

GEOLOGY

Vol. II
1902-1905

SAN FRANCISCO

PUBLISHED BY THE ACADEMY
1905

CONTENTS OF VOLUME II. THIRD SERIES,

GEOLOGY.

Plates I-XXXV.

PAGE

Title-page / i

Contents iii

No. 1. Cretaceous Deposits of the Pacific Coast. By Frank M.

Anderson. ( Plates I-XII ) v-lS4

(Published December 24, 1902)

No. 2. A Stratigraphic Study in the Mount Diablo Range of Cali-
fornia. By Frank M. Anderson. (Plates XIII-
XXXV) 155-248

(Published December 4, 1905)

December 30, 1914.

^SSlos:

PROCEEDINGS

OF THE

CALIFORNIA ACADEMY OF SCIENCES

Third Series
Geology Vol. II, No. i

Cretaceous Deposits

OF .THE

Pacific Coast

Frank M. Anderson

With Twelve Plates

Issued December 24, igo2

SAN FRANCISCO

Published by the Academy

T902

PUBLICATION 'COMMITTEE

Charles H. Gilbkrt, Chairman
Joseph W. Hobson William A. Setchell

PROCEEDINGS

OF THE

CALIFORNIA ACADEMY OF SCIENCES

Third Series
Geology Vol. II, No. i

Cretaceous Deposits

OF THE

Pacific Coast

Frank M. Anderson

With Twelve Plates

Issued December 24, 1902

SAN FRANCISCO

Published by the Academy

T902

JAN 14 1203

PREFACE.

This paper is the result of a study begun in 1894 ^pon
an interesting collection of Upper Cretaceous fossils from
a new locality in Southern Oregon, locally known as the
" Forty-Nine Mine," but referred to here as the Phoenix
Beds.

The special feature of interest in this collection is the
large percentage of individuals and species of the genera
Schloenbachia, Scaf kites, and the aberrant forms of cepha-
lopods, types for the most part that were unfamiliar upon
this Coast. The contents of this collection was referred to
in the May-June number of the Journal of Geology, 1895.

Since the first visit to this locality almost every year has
added new and important species from the same place, and
from a quite similar locality on the opposite and southern
slope of the Siskiyou Range, near the village of Henley,
Siskij^ou County, California. These two localities evi-
dently belong to the same coastal basin of the Cretaceous,
and are here included in what is called the Oregon Basin.

From this fauna the study was naturally led to the Chico
deposits of the Sacramento Valley, and from these to the
Horsetown and the whole of the Cretaceous.

In offering this paper for publication the author wishes
to acknowledge the kindly interest and assistance of his
instructors and co-workers, Drs. J. P. Smith, T. W. Stan-
ton, J. C. Merriam, and others, who have shown not only
professional courtesies, but have aided the work by a
friendly appreciation and a cooperative spirit.

The conclusions that have been reached by this study,
while they may not be final, are nevertheless believed to be
important in the development of our knowledge of West
Coast geology, and in the stud}' of the Great Past and its
biological and physical geography. F. M. A.

December 17, 1900.

( I ) Li] December 24, 1903.

CRETACEOUS DEPOSITS OF THE PACIFIC

COAST.

BY FRANK M. ANDERSON.

CONTENTS.
Plates I-XII.

Part I. page.

I. Introduction 4

II. Historical Review 6

III. Purpose of the Paper 10

IV. Stratigraphy of the Cretaceous. . 12

1. Basement Complex 12

2. The Sacramento Valley 14

3. The Oregon Basin 17

4. British Columbia 18

5. Southern Occurrences 20

6. Correlation 21

V. Faunal Changes of the Cretaceous 22

1. Recognized Diversity 22

2. Horizons Distinguished 24

The Chico Epoch 24

The Horsetozvn Epoch 40

The Paskenta Horizon 43

The Sub-Knoxville Horizon 47

VI. Disturbances of the Period 48

1. Distribution of the Horsetown Beds 48

2. The Chico-Knoxville Unconformity 50

3. The Peridotite Intrusions 53

4. The Chico Overlap 54

VII. Correlation of Deposits 55

1. The Sacramento Sections 56

2. Equivalents of the Chico 56

3. Equivalents of the Horsetown 63

4. Equivalents of the Knoxville 65

5. Cordilleran Oscillations 67

VIII. Summary and Conclusions 68

Part II.

Descriptions of Species 71

Literature Cited 127

Index 130

Explanation of Plates 132

CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

Part I.

I. Introduction.

The Cretaceous deposits of the Pacific Coast of North
America, as already known to geologists, lie within a narrow
continental border mainly to the west of the Great Basin
and the northern Cordillera. In their north and south
range the scattered and disconnected occurrences extend
from Mexico to Alaska and the Arctic Ocean, although they
do not territorially cover a large region. Represented upon
a map with other formations, they might hardly be noticed
except by one looking for them. They are but remnants,
or even mere traces, of what was once a more extensive
system of deposits, which in some places have been entirely
removed, and in others covered by later sediments, and in
some cases by volcanic flows. One of the largest and most
noteworthy of these remnants occupies the Sacramento
Valley in central-northern California, where it occurs in
unconnected dashes along its borders, in low hills flanking
the valley upon the east and west.

Southward in California, the Cretaceous rocks are spar-
ingly distributed, occurring only at intervals in the Coast
Ranges, where they either form some of the lesser ridges or
protrude from beneath ridges of later sediments. In the
extreme southern portion of the State, and in Lower Cali-
fornia, they are confined to a narrow belt in the immediate
neighborhood of the coast, buttressed against the older
crystalline rocks of the interior.

Northward in California, and in Southern Oregon, the
Cretaceous beds are restricted to the larger valleys lying
among the Klamath Mountains or upon their eastern out-
skirts; and here, also, they rest upon the older crystalline
or metamorphic rocks, and are overlaid by Tertiary or
Neocene deposits largely of fresh-water origin, or by
Neocene lavas.

Within the boundaries of the Great Basin, the only
Cretaceous rocks that have been reported rest in a similar
manner upon a complex of early Mesozoic and older rocks.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 5

in part crystalline, and in part metamorphic sediments, that
make up the mass of the Blue Mountains in northeastern
Oregon. Their limits have not been ascertained, but they
appear to flank these mountains upon the west much as they
do the Sierra Nevada in California; and here, also, they are
in turn overlaid by fresh-water Tertiary deposits and Neo-
cene lavas.

It would appear from what is known of the distribution
of the Cretaceous sediments south of the Columbia River,
and of the older basement series that in Cretaceous
time formed the floor and margin of the sea, that the
western coast-line of the Cordilleran continent in early
Cretaceous time was roughly determined by the three older
mountain groups, — the Sierra Nevada, the Klamath Moun-
tains, and the Blue Mountain system in northeastern
Oregon.

It is not yet proved that in later Cretaceous time the sea
extended along the whole eastern base of the Klamath
group, thus severing them wholly from the mainland, with
which they had previously been connected.

Cretaceous rocks are not definitely known in the coast
mountains of northwestern Oregon nor of Washington; yet
certain beds are known along the Columbia River opposite
Astoria, and in the Coast Ranges southward, that not im-
probably belong to this period. In the vicinity of Puget
Sound, in British Columbia, and on the adjacent islands,
the Cretaceous rocks have a distribution not less important
than they have in California. They rest here upon a base-
ment of earlier Mesozoic and older rocks, and extend east-
ward upon the flanks of the Cordilleran platform. As in
Oregon and northern California, these beds are found
occupying the chief valleys among a system of mountains
composed essentially of pre-Cretaceous rocks. Farther
north, on the southern coast of Alaska, Cretaceous beds
are reported in the vicinity of Cook's Inlet, Kodiak Island,
and on the Alaskan peninsula (Dall, 1895-96). They
occur also at Rink Rapids, upon the Arctic border of the
continent.

(2) October 23, 1902.

6 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

The fossil remains found in most of the Cretaceous
deposits throughout this vast stretch of continental border
show them to be for the most part of marine, and of littoral,
rather than of deep-sea origin.

II. Historical Review.

No other series of rocks upon the Pacific Coast has
received so much attention as those of the Cretaceous
period. It is perhaps due to their easy accessibility, and
to the extremely interesting character of their fauna, that so
many able contributions have been made to the literature of
West Coast Cretaceous. Yet we are far from knowing all
that is desirable concerning the stratigraphy and fauna of
this interesting period.

A brief review of the more important papers that have
appeared from time to time, and accordingly a summary
sketch of the development of our present knowledge of the
subject, is here included for the benefit of readers who may
not be familiar with what has already been done.

The first announcement of Cretaceous deposits in Cali-
fornia was by Dr. Trask (1856), in which he reported the
discovery of ammonites and baculites in " Tertiary strata."

Eight years later, in 1864, the first volume of the Paleon-
tology of California appeared, in which Mr. Gabb pub-
lished a large number of species from strata which he
designated as Divisions yl. and ^. of the Cretaceous series.
These are now known as distinct formations of Cretaceous
and Tertiary age. Afterwards, in the second volume of the
Paleontology of California, which appeared in 1869, Gabb
distinguished four horizons of the Cretaceous, which he
called respectively Shasta, Chico, Martinez and Tejon, the
last two of which are now known to be Eocene, or only in
part Cretaceous, as shown later.

The beds exposed at Horsetown, and along the North
Fork of the Cottonwood Creek, Shasta County, constituted
what was termed the Shasta Group. It was stated that it
contained fossils representing the ages from the Gault to
the Neocomian, inclusive, of the European Cretaceous.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 7

The Chico Group was made to embrace all of the occur-
rences of Cretaceous on the eastern side of the Sacramento
Valley, some important beds in the vicinity of Mount Diablo
and Martinez, in Southern Oregon, and the coal-bearing
deposits of Vancouver Island. It was correlated with the
Chalk of England, though not definitely with either division.

The Martinez was believed to be distinct from the Chico,
and was represented by beds at Mount Diablo, and near
Martinez, Contra Costa County.

In 1887, in connection with the work of the United
States Geological Survey upon the quicksilver deposits
of the Pacific Coast, Becker (1888) and White (1888 and
1889) revised the classification of the California Cretaceous,
recognizing essentially two divisions, the Lower and the
Upper, separated by an unconformity.

The Upper Cretaceous was called the Chico-Tejon, to
which were annexed, as probably conformable with it, the
Wallala Beds discovered by Becker on the coast of Sonoma
and Mendocino counties, at San Diego, and in Lower
California.

The Lower, or Shasta Group, was made to include not
only what is now recognized as properly belonging to that
division, but they placed in it also a great series of meta-
morphic rocks occurring in the Coast Ranges, as well as
the Mariposa formation of the western Sierra Nevada, both
of which are now known to be distinct from it. The lower
portion of the Shasta Group was called the Knoxville, from
its occurrence, with its typical fauna, at Knoxville in Napa
County. The upper portion of the Shasta, or the Horse-
town stage, was thought to be perhaps a portion of the
same series, and involved with the Knoxville in the "pre-
Wallala upheaval."

It was afterwards shown by A. Hyatt (1894), J. S. Dil-
ler (1894) ^"d J- P- Smith (1894) that the former view
held by Professor Whitney regarding an unconformity
between the Mariposa and Cretaceous strata was correct;
that after the folding and metamorphism of the Mariposa
slates the Cretaceous subsidence of the region had been

8 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

inaugurated. An unconformity was also established by
paleontological evidence, and the confusion that existed in
regard to the various species of Aucella was finally settled.

Paralleling in the Coast Ranges this separation of the
Mariposa formation from the Cretaceous, the rocks that
were thought to belong to the Shasta Group have been
shown to consist of two unconformable series. It is due
largely to the work of H. W. Fairbanks (1892, 1893, 1895,
1896), Diller and Stanton (1894) and J. S. Diller(i893) that
certain metamorphic and semi-metamorphic rocks of the
Coast Ranges and the Klamath Mountains are recognized
as lying unconformably below the Aticella-hQ^irmg shales,
which have been called Knoxville.

The Cretaceous series has been found to contain few, if
any, rocks that have suffered a high degree of metamor-
phism. The older complex is composed of both igneous
and stratified rocks that may eventually prove to include
members of Paleozoic, as well as of Mesozoic age, embrac-
ing the Santa Lucia series of Willis (1900) and at least a
portion of the Franciscan (Lawson, 1895), or Golden
Gate (Fairbanks, 1895) series. The latter series was
named from its important development in the vicinity of
San Francisco Bay; it extends southward from the Klam-
ath Mountains along- the coast of California, and in the
Coast Ranges forms the basement of many later deposits.
The Franciscan series is generally believed to be in part
Cretaceous ; but much of it, including the Radiolarian
cherts and some of the limestones and slates, is known to
antedate the Cretaceous.

In the paper by Diller and Stanton (1894), referred
to above, it is shown that in the upper Sacramento Valley,
on the flanks of the Klamath Mountains, beds that have
been called Knoxville overlie unconformably an older
metamorphic series, partly sedimentary, and partly igneous
and cr3'stalline. The Cretaceous series was carefully
studied in two more or less complete sections on the
western side of the Sacramento Valley, ranging eastward
from the Yallo Bally and Bally Choop mountains. The

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 9

result has been a revision and reclassification of the Creta-
ceous deposits, and the publication of some surprising facts
connected with their occurrence and deposition. The
astonishing thickness of these sediments in their deep-
est section seems almost incredible, especiall}' when one
considers the limited dimensions of their basin, and the enor-
mous movements necessary for their formation and subse-
quent folding. According to the estimates of these writers,
about thirty thousand feet of sediments accumulated in the
basin of the Sacramento without the intervention of any
great disturbances, and during a period of continuous and
prolonged subsidence. They have accordingly included
in a continuous series all the strata of wKat is called the
Shasta-Chico series, embracing the Chico, Horsetown, and
Knoxville, and including rocks below the lowest Aitcella-
bearing horizon. They recognize faunal changes in the
series, but no decided breaks.

Dr. T. W. Stanton (1895) published an extended list
of Knoxville species, obtained from beds in the Shasta-
Chico series below the upper limit of the range of the genus
Aticella. More than fifty species are added by this con-
tribution to the fauna previously known as belonging to this
division. These species occur mainly in the upper portion
of the Knoxville, within three thousand feet, stratigraph-
ically, of what is believed to be the upper limit of the
range of Aucelhi.

From a more recent paper by the same author (Stanton,
1897), it would appear that the Knoxville strata are to be
correlated with the Comanche series of Hill, including the
Trinity and Washita divisions. The Cretaceous series of
California, south of Tehama County, has been less studied,
but seems to be less simple than it is at the north.

Fairbanks has reported in the neighborhood of San Luis
Obispo a distinct unconformity between Atice/Za-hearing
and Chico strata.

It has also been shown by both Stanton (1895, 1895-96)
and J. C. Merriam (1897) that the Martinez Group of Gabb
consists of two parts, one indistinguishable from the Chico,

lO CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

and the other more nearly related to the Eocene. The
upper division was designated the Martinez by Merriam.
Between the typical Chico and the Martinez, as thus
restricted, there is found to be neither a faunal nor a
stratigraphic continuity, and the Martinez is provisionally
classed with the Eocene.

A similar series of Cretaceous deposits has been found in
British Columbia and the adjacent islands by the geologists
of the Canadian Geological Survey (Whiteaves, 1893).
On Queen Charlotte Islands and the Island of Vancouver a
succession of strata has been shown to range from the
Lower Cretaceous or even Jurassic, upward to horizons
equivalent to the Chico of California, There is not, how-
ever, the apparent continuity in these beds that is claimed
for the California series. But the fuller statement of their
relations will be continued later.

In central Mexico, near Catorce (Nikitin, 1890), fos-
siliferous beds occur which have been referred to the
Jurassic, but which Dr. Stanton thinks are probably to be
correlated in part with the Knoxville of California (Stanton,
1895, p. 26, etc.). The Aticellce and some of the ammon-
ites are said to be very similar if not identical with Califor-
nia species.

Many important contributions to West Coast Cretaceous
geology that are not here mentioned will be referred to
later.

III. Purpose of the Paper.

The objects of the following discussion are primarily
threefold. First, it is desirable to place in a more connected
account the essential facts in regard to the Cretaceous
deposits of the Pacific Coast, and particularly of California,
with reference to their distribution, the physical conditions of
their deposition, their disturbances, subsequent erosion, and
other features of importance; and to add something as to the
relations they bear to other formations with which they are
territorially connected. Second, it is thought that a more

Gkol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. II

complete classification of the series can be made, in which
there shall appear its diversit}^ and complexity, as well as
its unity. It is accordingly the aim to give here what are
thought to be the most natural divisions of the series, which
shall recognize both its physical and faunal changes in their
more important phases, and call attention also to the devel-
opment of its fauna in geological time. Third, it is possible
to correlate with more precision than has yet been done the
various members of the California section with those of
neighboring basins, neighboring American provinces, and
other countries bordering the Pacific, if not also with the
Atlantic and Indian oceans. Furthermore, many new and
interesting fossil forms occur in the Cretaceous of California
and Oregon, and many types whose close affinities with east
Asiatic and Atlantic species have not yet been sufficiently
recognized.

Probably no other formation is so favorable as the
Cretaceous for the study of the distribution and historical
development of the faunas embraced within its limits. The
study of these problems may easily lead to the recognition
of important changes that have taken place in the physical
geography of North America and of the Pacific basin. In
this connection it may be said that the limitations that are
at present accepted for the different divisions of the Creta-
ceous series of California may be subject to some important
alterations, and that the closer discrimination of horizons
is both desirable and possible.

The physiography of California and Oregon, and perhaps
of other West Coast regions during the Cretaceous, which
ought to be connected with a study of this period, is not
yet sufficient!}^ recognized, although of more than ordinary
interest. Not only is the general shore-fine of the Creta-
ceous ocean approximate!}^ known, but the principal inlets
that indented the shore of that time may be clearly shown.
Something also of the drainage and configuration of the
surface may be inferred.

12 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

IV. Stratigraphy of the Cretaceous.
I. Basement Complex.

In the foregoing review it was stated that the Cretaceous
deposits of the West Coast are found, for the most part,
occupying the present valleys, which are the results of a
pre-Cretaceous folding, not yet obliterated. This fact is
worthy of being further emphasized, since it is not yet suf-
ficiently recognized. It can be shown in many ways that
this distribution of the Cretaceous rocks is not to be attrib-
uted to erosion, but it represents the original conditions of
Cretaceous and pre-Cretaceous physiography.

It has already been shown by Diller and Stanton (1894),
by J. P. Smith (1894), ^"^ others, that the unconformity
between the Knoxville beds and those of the older Mesozoic
and pre-Mesozoic ages represents an uplift and period of
land erosion prior to the Cretaceous deposition.

Dr. Smith places this period of folding, metamorphism,
and erosion at the close of the Mariposa epoch, or in late
Jurassic time. Indeed, it is now the opinion of most geol-
ogists that the prime movement (perhaps the intrusion) of
the granitic core of the Sierra Nevada occurred at this
period and was unquestionably the principal agent of both
the folding and metamorphism of the pre-Cretaceous sedi-
mentary rocks. Undoubtedly the diversification of the
surface was considerable before the inauguration of the
Cretaceous period, notwithstanding the subaerial reduction
during the long land interval following the Mariposa epoch.

It is interesting to remember in this connection the two
parallel granitic axes of the Pacific border, most noticeable
in the central portion of California, between which most of
the Cretaceous and later deposits lie. It might be better to
refer them only to borders of the Great Valley region of
CaHfornia, were it not for the suggestiveness of well known
facts outside of this latitude.

Nearly parallel to the granitic core of the Sierra Nevada,
a similar granite massif follows the coast from Santa

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 1 3

Barbara County northward toward Sonoma. It is involved
in a number of lesser ranges along the coast, among which
are the Santa Lucia, Santa Cruz, and Montara ranges, and
others on the coast north of San Francisco. The age of
these granites is a matter of uncertainty, and it is conjec-
tural to suppose that their movements have been contempo-
raneous with those of the Sierra Nevada; but this is
immaterial so far as the Cretaceous deposits are concerned,
which, as has been said, occupy a position for the most
part intermediate between the two, and only occasionally
touch the granites of either mass.

The components of the basement series upon which they
rest are of various ages, and have roughly a concentric
arrangement with reference to the Great Valley, forming a
succession, inward, of Paleozoic and earlier Mesozoic
rocks. The latest of these whose age is definitely known
are the Mariposa slates of the Sierra foot-hills. In the
Coast Ranges the unconformity of the Knoxville strata upon
those of the Franciscan series, as at Mount Diablo, Santa
Margarita, and other places, makes it apparent that this
formation, which is probably also of Mesozoic age, forms
a part of the basement of the Shasta-Chico series. Beyond
the Mariposa slates on the east are the still older rocks of
the Calaveras formation, while in the Coast Ranges, between
the strata of the Franciscan series and the coastal granites,
is found a series of ancient crystalline marbles and quartz-
ites that can hardly be thought younger than the Paleozoic.
Concentrically with these, tnough often overlapping them,
are the later Mesozoic rocks of the Cretaceous, ranged
along the borders of the Great Valley.

Northward, in the Klamath Mountains, the underlying
rocks range down in age even to the Devonian and older.
Near Yreka, in Siskiyou County, Cretaceous deposits are
found resting upon a series of micaceous and quartz-schists
of either Devonian or earlier age. Throughout the region
these schists are mantled over by a series of slates, gener-
ally either silicious or calcareous, that remind one strongly

14 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

of the slates and jaspers of the Franciscan series. The
true relations of these slates to the Devonian rocks in the
vicinity of Gazelle, in the same county, are not definitely
known, though probably they include the strata of the
Scott River Valley, referred to by Diller and Schuchert
(1894) as probably Triassic.

In Southern Oregon the basement rocks are largely simi-
lar. Occasionally granitic rocks form the floor for Creta-
ceous sediments, as at Ashland, Oregon, in the vicinity of
Horsetown, and on some of the tributaries of the Cotton-
wood Creek, Shasta County, and a stream of the same
name in Siskiyou County, — California. But generally
upon either margin of the Cretaceous basin there are found
the folded and eroded older sediments. Thus both the
situation and the distribution of the Cretaceous deposits
are suggestive as to their period of folding; but the
evidence is far from resting here. There are facts of
erosion in the Klamath Mountains that furnish confirmatory
evidence.

2. The Sacramento Valley.

The Shasta-Chico series, as represented in the upper
Sacramento Valley, where it has been described by Diller,
and afterward by Diller and Stanton, is said to consist of
about thirty thousand feet of strata in which the sediments
vary from conglomerates to sandstones and clay shales.
The lower nineteen thousand nine hundred feet of the
section along Elder Creek, Tehama County, is composed
chiefly of shales with a subordinate amount of sandstone
and of conglomerates, often of only local occurrence.
Higher in the section, sandstones become more abundant,
until at twenty-six thousand feet they give place to massive
conglomerates and sandstones. The whole series has a
varying dip to the eastward or southeastward, being near
the base often nearly vertical, but generally not exceeding
an inclination of thirty degrees. Toward the top it is
sometimes but little disturbed.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 15

The fossiliferous portion of this series has been divided
into three divisions, mainly upon faunal characteristics.
The lower nineteen thousand nine hundred feet contain an
abundance oiAucellce, of not more than two or three species,
several species of Cephalopoda and other mollusks, also
plant remains. This is the portion of the Cretaceous series
to which the name Knoxville has been appHed.

Stanton placed the upper Hmit of the Knoxville at the
upper limit of the range oi Aiicella. Mr. Diller (1893, p.
211) at one time stated that in the lower nineteen thousand
nine hundred feet of the Elder Creek section the only fossil
found was Aucella; and in another paper Stanton says that
they are often so abundant in the strata that it would seem
they must have monopolized the bottom of the sea. Later,
however, Stanton (1895, pp. 11-85) pubHshed a large
number of species as belonging to the Knoxville, many of
which have come from the strata of this section or near it.
But it is to be noted that the entire list of molluscan and
cephalopod species added to the fauna of the Knoxville
from this section has been found almost if not entirely within
three thousand feet of the upper limit of the Knoxville, or
in other words, within this distance stratigraphically of the
upper limit of the range of Aucella.

With the appearance of this new fauna at the top of the
Knoxville, as then defined, the number of AucellcB gradually
diminishes. This fact will be referred to further on.

Above the upper limit of Aucella the shales continue
uninterrupted, though becoming more sandy, for about six
thousand feet, when they give place to conglomerates. It
is the sandy and conglomeratic portion, confined to the
uppermost four thousand feet of the series, that has been
referred to the Chico division; while between this horizon
and the Knoxville are the Horsetown strata.

The section along Cottonwood Creek, Shasta County,
some fifteen or twenty miles north of Elder Creek, corre-
sponds closely with that already described in so far as the
series is represented. On the Cold Fork of the Cottonwood

l6 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

it consists of the Knoxville with the overlying Horsetown
and Chico strata; while on the North Fork the base of
the Horsetown rests directly upon the older metamorphic
and granitic rocks.

Along the eastern side of the Sacramento Valley, in the
foot-hills of the Sierra Nevada, only the upper portion of
the series has been found, resting upon the metamorphic
rocks of the "Gold Belt." Here the horizon, which
perhaps should be considered as most typical Chico, is to
be seen, though Gabb evidently included under that name
more than is there represented. Diller states that the beds
along the eastern side of the valley are much less disturbed
than those on the west, being often nearly horizontal. The
entire Cretaceous series, as has been shown by former
writers, forms in the northern half of the Great Valley a
geosyncline, which in its central portion passes below and
is hidden by the accumulation of Tertiary and later strata,
but which reaches the surface along both borders of the
valley in the foot-hills of the Coast Ranges and Sierra
Nevada.

In the papers already cited, Mr. Diller has shown that
the Cretaceous series of the West Coast, as is illustrated by
the deposits of the Sacramento Valley, was laid down
under conditions of prolonged subsidence. A continuous
though unequal settling of the sea-bottom from first to last
is apparently demonstrated not only by the continuous and
unbroken order of the series above described, all of which
seems to indicate shallow water, but also by the successive
overlapping and transgression outward of the younger por-
tions of the series upon the border of older rocks that
circumscribed the Cretaceous waters at each -epoch. The
differential action of this movement in the coast regions
cannot be better stated than in Mr. Diller's words (Diller and
Stanton, 1894, p. 456). He says : "The large extent of this
subsidence, from Alaska on the north to Lower California
on the south, makes it an epeirogenic movement. There is
evidence, however, that the movement, although epeirogenic,

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 1 7

was not uniform throughout the whole area. * * *
and it appears that the subsidence was greater in the
Sacramento Valley than in the region of the Coast Range
and Sierra Nevada." And continuing the same topic he
adds: "If the subsidence was uniform throughout the
whole region it follows that what is now the western foot of
the Sierra Nevada, as well as the corresponding portion
of the Coast Range, where in both cases the Chico rests
directly upon the folded pre-Cretaceous rocks, must have
been at an elevation of twenty-five thousand feet above the
sea when the basal portion of the Knoxville was deposited
in the Sacramento Valley. This hardly seems possible, for
we know of no such mountains in the country to-day. It
seems much more probable that the subsidence was not
uniform."

It is probable that at no time during the subsidence was
the whole of either the Sierra Nevada or Klamath Mount-
ains below the sea. Scattered areas of Cretaceous deposits
occur among the Klamath Mountains west of the Sacra-
mento Valley; but it is not necessary to suppose that the
sea reached these localities across mountain summits.
More likely it found its way into earlier basins through inlets
from the open ocean at the west. This was undoubtedly
the case in Southern Oregon, where portions of the same
series are represented in different places.

3. The Oregon Basin.

In Rogue River Valley, beds of Upper Cretaceous age
occur, following generally the western side of the valley,
and resting tipon the older metamorphic slates and crystal-
line rocks, with a fairly uniform dip toward the east. The
strata consist for the most part of sandstones and conglom-
erates, with a subordinate amount of shales. The con-
glomerates predominate in the upper part of the section,
while shales are common at and near the bottom. These
beds are apparently equivalent to those of the Upper

l8 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

Cretaceous of the Sacramento Valley, to which they will be
compared in more detail in another section. Similar beds
are found in northern California.

In Douglas County, near Riddles, is a syncline of Creta-
ceous strata folded between areas of older metamorphic and
intrusive rocks. Lithologically it is a repetition of the
equivalent portion of the Shasta-Chico series at the south,
consisting of shales, sandstones, and conglomerates. The
conglomerates are said by G. F. Becker (1891), who first
described the section, to predominate in the upper part of
the series, and to be very extensive. Only the middle por-
tion of the Sacramento section is represented in these beds,
which are in part Knoxville and in part belong to the
Horsetown. Chico strata have not been reported for this
immediate locality, but they occur at some distance to the
southeast on tributaries of Rogue River.

These Oregon deposits, especially the lower strata,
appear to belong to an embayment distinct from that of the
Sacramento Valley; but they show a similar transgression
of the later members of the series, only in this case the
expansions were toward the southeast.

4. British Columbia.

Upon the mainland and islands of British Columbia the
Cretaceous deposits form a series of considerable impor-
tance, which, while not so connected as that of California,
is almost as complete, and is, perhaps, entirely comparable
to it. Aucella-hQ.'A.x'wi^ strata which perhaps form the bottom
of the series are found both upon the mainland and upon
the Queen Charlotte Islands. The following tabular view
after Dawson (1889, P- ^27) represents the Cretaceous
series of these islands, to which are annexed a few of
the fossil species characteristic of each division.

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS.

Division.

strata. Thickness.

Important Species.

A.
B.

Upper shales
and sandstones

Coarse
conglomerates.

Lower shales
and sandstones
(with coal )

Agglomerates.

1500'
2000'

5000'

^■500'

Inoceramus labiatus.

Belemnites sp.

iLytoceras sacya, L. timotheum,
1 Desmoceras breweri,
D. dawsoni, and D. plattulatum.
\Aucella, Perisphinctes, etc.

Lower

sandstones.

1000'

.... Pleuroniya lavigata, Neniodon,
etc.

The lower portion of "Division C" perhaps ought not to
be included in this part of the section, and may eventually
prove to be equivalent to the ^wce//«-bearing beds of
Tatlahcoh Lake, and to represent also a horizon consider-
ably below the upper portion of C . Farther south, upon
the northern end of Vancouver Island, in the vicinity of
Quatsino Sound, the three upper members of this series
are found. Here also Aucella and other species are
reported which appear to belong to the Knoxville.

At the southern end of Vancouver's Island, near Comox
and Nanaimo, strata occur that have been correlated with
the Chico of California ; they consist of shales and conglom-
erates, amounting in thickness to about five thousand feet.
These deposits contain the coal-bearing beds of Vancouver's
and the neighboring islands. Still further southward, on
the borders of Puget Sound, is the coal-bearing Puget
Group of White (1889), which has been compared to the
Laramie, a series that is thought to be of Tertiary age, or
at least later than the Chico.

The relative position of these deposits, all of which rest
directly upon earlier Mesozoic or older rocks, suggests a
Cretaceous basin extending southward, in which there was
a continued subsidence and transgression of the sea similar

20 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

to that already described for Oregon and California. This
was the view held by Dawson (1890) prior to the recogni-
tion of the fact in Californian deposits. Similarly the
Cretaceous deposits upon the mainland of British Columbia
are said to occupy basins in older metamorphic rock.

South of Puget Sound massive beds of conglomerate
occur along the Columbia River, which may belong with
those of the upper portion of the Nanaimo Group. They
contain few fossils ; yet such as they are they may well be
taken to support this view.

yl?^d:^//«-b earing deposits are reported from different
points along the Alaskan coast (Dall, 1895-96), as at Cook's
Inlet, Kodiak Island, the Alaskan peninsula, etc. Whether
they belong to the Cretaceous or Jurassic age has not been
settled; yet undoubtedly some of the species are of Creta-
ceous type. Chico deposits are now known to occur near
the mouth of the Yukon River, Alaska. Much of the
rock is a shale, either clay or calcareous, but limestones,
sandstones, and even conglomerates occur with Mesozoic
fossils. ylwc^//rt-b earing rocks are also reported from
Porcupine, Lewis, and Yukon rivers.

5. Southern Occurrences.

Southward from California there are but few deposits
known that can be classed as belonging to the Pacific
province, which will be mentioned here.

Near Catorce, in the state of San Luis Potosi, Mexico,
an Attce//a-hed.rmg formation has been described (Felix
and Lenk, 1890), which Dr. Stanton (1895, pp. 25-27)
thinks is equivalent in part to the Knoxville. Also in
southern Mexico are beds that have been referred to the
Lower Cretaceous, and are thought to represent a portion
of the Knoxville ; but too little is known of these deposits
for exact correlation.

Upon the island of Quiriquina, off the west coast of Chili,
Upper Cretaceous deposits occur resting upon schists of un-
certain age, and in turn overlaid by Tertiary beds. The
Cretaceous deposits consist of calcareous and glauconitic

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 21

sandstone, with basal conglomerates, all of marine origin,
and containing several fossil species common in the Upper
Cretaceous of California. Besides the molluscan remains,
these deposits contain several species of saurians and certain
plants, some of which have been described by Steinmann
(1895) and his associates.

6. Correlation.

But little can be done at correlating these widely separated
deposits upon purely stratigraphical resemblances. In no
one section is there a series that can find its exact parallel
in any other, much less in all the others. It is to be
noticed throughout, however, that the cycle of sedimentation
in these deposits is the reverse of the normal order. Shales
invariably are more abundant in the lower part of the sec-
tions, sandstones increase as one ascends the series, and
conglomerates are more common in the upper portions.
This is sometimes so, even where there is only a part of the
entire series present, as in the vicinity of Medford and
Ashland, in Rogue River Valley, Oregon. Yet this is not
always so; at Horsetown and at Ono, Shasta County, the
local base of the Cretaceous contains heavy beds of con-
glomerate. But little reliance can be placed in these con-
glomerates, however; for as Diller has stated, they are
often of only local extent, and may merely show the position
of some stream in mid-Cretaceous time. Their irregularity
nevertheless affords some interesting suggestions.

The regional subsidence and the deposition of these beds
could not have been quite so continuous as has been imag-
ined, thouofh the disturbances have been more or less local;
still, there are some broad uniformities- noticeable in the
widely distributed deposits. Tawny or grayish sandstones
and pebbly conglomerates characterize the Chico and Upper
Horsetown ; while dark or yellowish clay shales are more
common in the Knoxville portion of the series. If the

(3) October 28, 1902.

22 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

heavy beds of conglomerate in the vicinity of Riddles,
Oregon, really belong, as Becker believed, at the top of
the section, their apparent extensiveness would justify their
being compared to the conglomerates of "Division i?" of
the Queen Charlotte Islands section ; and they might also
find their equivalents in the sections of California.

V. Faunal Changes of the Cretaceous.

I. Recognized Diversity.

The work of Diller and Stanton has demonstrated how
little was previously known concerning the Cretaceous
series of California. From their study of the Cretaceous
deposits in the Sacramento Valley, they have felt compelled
to abandon the views of earlier writers regarding the com-
plexity of the series; while on the other hand, they have
emphasized the evidence of unbroken stratigraphic succes-
sion from bottom to top. Less effort has been made to
represent its actual diversification, either physical or faunal,
whatever this may be; and accordingly it remains to be
seen how far from simple were the conditions of deposition
in the Pacific border province during Cretaceous time ; yet
it appears that sufficient has been known for arriving safely
at conclusions somewhat different from those reached in
the accepted summary of our knowledge.

It is entirely natural that the historical development of
the subject should be as it has been. Early collectors
working less thoroughly over the scattered deposits have
noticed the more striking dissimilarities without being able
to recognize connecting elements that a more detailed
study has discovered. Attention has been called to the
physical peculiarities of the Sacramento section of the Cre-
taceous, which shows on the whole a cycle of sedimenta-
tion somewhat the reverse of the normal. There is a certain
evidence in this fact that leads one to suspect that the

Geol.— Vol. IT.] ANDERSON— CRETACEOUS DEPOSITS. 23

series as a whole is not altogether simple, and that in the
closing epochs disturbances were both more numerous and
more general. Similarly, when the series is made the sub-
ject of faunal study, a diversity that is still more significant
is soon recognized. The faunal differences that are ordi-
narily seen have led to the distinctions hitherto made, and
to the divisions of the series settled upon by the earlier
writers; but these differences are real and not merely
apparent. It is evident to one coming from the fossiliferous
beds upon the eastern border of the valley, where gastro-
pods and bivalves largely predominate, to the beds of the
Cottonwood, where cephalopods are so common, that one
has reached an entirely different faunal horizon. So, also,
when one proceeds to the more basal portions of the series
in the foot-hills of the Coast Ranges, one finds again a
complete faunal change. The cephalopods of the last hori-
zon gave place to a fauna composed almost entirely of one
or two species of Aiicella. These facts led to the recogni-
tion of the three horizons commonly known as the Chico,
Horsetown, and Knoxville, which, in spite of the connect-
ing elements uniting them, have not yet been, and ought
not to be, abandoned. Indeed, it is not improbable that
upon further study additional reasons will be found for still
further enforcing the distinctions, and even, as it now
appears, of subdividing some of the principal divisions that
are at present accepted as paleontological units.

Both Diller and Stanton have been convinced of the
transitional character of the fauna from one level to another
in different parts of the series. New forms appear succes-
sively and continue for unequal periods and disappear at
different stages of the overlying series. Some forms are
of short duration and some are very much more persistent.
Many lists of species taken from different localities and
representing different horizons have been published, which
apparently show this; and undoubtedly within certain limits
there is a more or less gradual change, and for some pur-
poses these facts may well deserve attention. Yet the

24 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

changes in the total faunas, as well as they can be known
from the fragmentary collections that have been made and
studied, do not seem to warrant the assertion of a uniformly
transitional series, and perhaps this has not been claimed
Yet the breaks that had previously been conceived to exist
between the main divisions of the series were bridged over
or minimized by the passage across them of many impor-
tant forms. Thus it was left to be inferred that the transi-
tion from the Horsetown to the Lower Chico might not be
different from that between different parts of the Horse-
town itself, except perhaps locally. But our knowledge of
the fauna as a whole, of each of the different horizons
above named, has gradually become more complete by the
continual contributions that have from time to time been
made; and while it can not be called quite satisfactory, yet
on the whole it may be regarded as sufficient for at least
some general observations. It must be borne in mind,
however, that the Cretaceous species of California need a
revision before any final conclusions can be established or
an entirely reliable correlation made, based upon paleonto-
logical evidence. Much confusion has undoubtedly existed
in regard to the limits and range of certain species, that has
often resulted from laxness in the identification of species.
In the subjoined portion of this paper attention is called
to a few of the many corrections that are needed for a
more satisfactory treatment of the subject, and which a
successful treatment will demand. However, for the pres-
ent there are some general facts that may be clearly
established.

2. Horizons Distinguished.

The Chico Efoch.

Regarding each division of the Cretaceous separately,
the fossil lists contributed by a number of its recognized
localities may be massed together, and by this means a
more complete idea of its general fauna can be gained than

Gbol— Vol. II.] ANDERSOM— CRETACEOUS DEPOSITS. 25

if but a few of its localities are taken independently. It is
found in this way that there are recognizable elements
apparent in each fauna, which may be safely depended
upon, and that while there is more or less of a transitional
character in the fauna of a given level, yet it does not
depart from the main type to any considerable extent until
the time arrives for an almost complete change. The
Horsetown fauna, for example, consists of a large number
of cephalopod forms, which is as great if not greater than
the whole number of other mollusks combined. This can
not be claimed for the Chico upon the eastern side of the
valley, where the whole number of cephalopods known is
not greater than one-eighth of the number of other mol-
lusks, and even in the strata immediately overlying the
Horsetown upon the west, which have been hitherto re-
ferred to the Chico, the proportion of cephalopods known
is not more than one-third that of the others. The rapid
increase in the number of gastropod and bivalve species
in the Chico is, however, the noteworthy fact; while at the
same time, the number of cephalopods as rapidly dimin-
ishes, except, perhaps, in more favored localities.

In the Great Valley basin of California the transition of
faunas is more gradual than it has been in any other basin
of the Pacific border; and for that reason the faunas repre-
sentative of the different horizons are not so easily distin-
guished. For purposes of correlation, therefore, it is safer
to select for study, if possible, localities lying outside of the
boundaries of the Great Valley, in which these distinctions
can be more readily made. And for the Chico epoch this
is both possible and especially desirable. The faunas of
the Chico are therefore represented in the following lists,
massed from a number of the more significant localities, as
will be shown later. Each division of the Chico, the Upper
and the Lower, is represented by four^ such localities,
the lists being for the most part compiled, in a somewhat
revised form, from others already published. For the
Upper Chico the localities selected are in the Sacramento

26 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

Valley, and have been well described by Gabb, White, and
others; while for the older division of the same epoch the
localities are mostly new or have not yet become perfectly
known. It seems to be especially important that the Lower
Chico should be studied in such a manner.

Of the Lower Chico localities selected for study, two lie
to the north and two to the south of the Great Valley basin,
and are as follows: {a) near Phoenix, Jackson County, Or-
egon; (<5) Henlev, Siskiyou County, California; (c) Silver-
ado Canyon (Bowers, 1890), Orange County, California;
(<^/) near San Diego, San Diego County, California, including
localities at Point Loma and La Jolla.

Locality (c), Silverado Canyon, is intended to represent
the Lower Chico beds of the Santa Ana Mountains,
Orange County. The fauna of this horizon has recently
been reinforced by collections sent to the State University
by Dr. Stephen Bowers of Los Angeles. Some of the
localities from which his collections were made are very
near the Silverado Canyon, and hence are included with it.
Bowers' Canyon is thirty miles northwest of Los Angeles,
and from the fossils furnished by this locality it belongs to
the same horizon.

Species occur in the following lists that are referred
to locality (c) by use of the letter '* R," as explained
in the foot-note.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS.

List of Fossil Species from Chico Localities.^

Upper.

Lower.

w -

Texas
Flat

s 1

ft '

n
<<

-1
p

Acanthoceras cotnpressmn, sp. nov |

Acatithoceras navicular e ^L\NT

Acanthoceras rotoniagense Stol

Anrvlnrpra's lineatutn Gabb

Ancyloceras ( ? ) quadratum Gabb

Finrulifp'i rhicopn'iis Trask =t

Baculites fairbanksi, sp. nov

fiarulitp'i sn

Desnioceras ashlandicum, sp. nov

Desmoceras hoffmanni Gabb

Desnioceras siigatum Forbes

■J*

Hamites armatus, sp. nov

Hamites cylindraceus De France

if-

Hamites ellipticus, sp. nov

Hamites phcenixensis, sp. nov

Hamites vancouverensis

J-fp]inrpv(i'\ lireweri Gabb

Helioceras declive Gabb

1-fp]inrpvn ^ ^n

Heteroceras cooperi Gabb

Heteroceras r^\^ H. reussianum d'Orb...

f-fnhJitpK yp77tOfttii Garr.

/ vfnrprn'i hafp'si Garb

Lytoceras jacksonense, sp. nov

T vtnrpvn^ iukp'si f ■'1 Sharpe

*■

r vfnrprn'i larva Forbes

Mortoniceras crefiulatuin, sp. nov

Nautilus danicus ( ? ) Schloth

Mniitilii^ sn

♦p

Pachydiscus newberryanus Meek

Pftrhvdi^rw! sd

Phvllnrprn'i ra)HOSUin Meek

Placenticeras cali/ornicum, sp. nov

i
1

1 In the following lists, K = reported, S = substituted from neighboring and equiva-
lent deposits, ? = identity doubtful.

28 CALIFORNIA ACADEMY OF SCIENCES.

[PROC. 3D Ser.

Upper.

LOWKR.

if''

n n

50 ►«

San
Diego.

Silverado.

Pl/yr/'iifir/'vnt: -hn ri /iruin Smith

J^irin^jnf'i^nhi ^ hi^fl'il'ilPVI mi flOV

Ptychoceras sp

'\rnhhHt"\ rnndoni sn nov

'srn'hhUpK cilliKi sn nov

'\rnhhifp'\ inertni'! sn nov

'\rnhhitp<i klninn{hpn'\i% sn nov

Scai)hites ■bewini SD. nov

^rnhhitp^ vcip'upn'si's. sn nov

*■

Srhl(Enbachia bakeri SD. nov

■Jt

Schloenbachia blanfordiana ( ? ) Stol

'srhlrpnhnrhia. hufffn'ii'; sn nov

Schloenbachia chicoensis Trask

■J*

Schlcenbachia (rcibbi. sd. nov

Schlcenbachia knie'hteni, sd. nov

»f

Schlcenbachia miilticosla, sp. nov

Schloenbachia oregonejtsis, sp. nov

■K

*■

SrlihrnheirhicL ■hvot>inaucL Stol

■»(-

Schloenb'chia siskiyoueiisis, sp. nov

■*f

Schloenbachia sp. undt

■if

Schlcetibachia sp. undt

Aciceon inornatus Gabb

ArffT'on ifup'ili'; Stol

Actcconella oviforniis Gabb

AftcEonina califoynica Gabb

Aclceonina pupoidcs Gabb

Actfxonina sp

Actceonina sp

AinauYopsis alveata Gabb

Aniauropsis ovi/omiis Gabb

Anchura calif ornica Gabb

Anchura condoniana^ sp. nov

Anchnra falciforniis Gabb

Ancillaria elongala Gabb

Angaria ornatissima Gabb

■»f

■jf

Geol.-Vol. II.] ANDERSON— CRETACEOUS DEPOSITS.

Architedonica mornata Gabb
Architedonica veatdii Gabb .

Bulla sp

Calliostoma sp

Calliostoina radiata Gabb

Cerithiutn pilingi White

Cheinnitzia sp

Chentnitzia planulata Gabb . . .

Cinulia obliqua Gabb ,

Cotninella lecontei White

Cylic/iJia costata Gabb ,

Deiitaliuin cooperi Gabb

Dentalimn siraniineuin Gabb,

Discohelix leana Gabb

Eniarginula radiata Gabb. . . ,

Erato veraghooretisis ( ? )

Eripachya ponderosa Gabb . .
Faunus mariciduliis White. .

Fulgur hilgardi White

Fulguraria gabbi White

Fhsus averilla Gabb

Globiconcha renwndi Gabb. - .
Gyrodes co7iradiana Gabb . . . .

Gyrodes expansa Gabb

Gyrodes pansa Stol

Haliotis loniaensis, sp. nov.. . ,

Haydenia iuipressa Gabb

Helcyun dichotoma Gabb.

Littorina compada Gabb

Lunatia pagoda Forbes

Lysis duplicosta Gabb

Lysis oppansa White

Margaritella globosa Gabb . . .

Mesalia obtusa Gabb

Nerita cuneata Gabb

Uppkr.

(Kl 5

n ^■
n n
fro

53 O

" 2

• 93

Lower.

s
s

CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

Upper.

Op a

Patella traski Gabb

Perissolax brevirostris Gabb j ^

Phasionella sp

Potarnides tenuis Gabb

Ringicula varia Gabb

Scobinella dilleri White r

Stomatia sucicensis White

Straparolliis lens Gabb

Straparolbis paucivolvus Gabb

Trito7iiuin sp

Trochiis goni/erus White

Trophon condoni White j

Turritella chicoensis Gabb | »

Turritella robiista Gabb «

Turritella seriatini-granulata Gabb. . . .

Turritella veatchi Gabb

Vasculum obliquum White

Anatina inequalateralis Gabb

Anomia sp

Asaphis undulata Gabb

Astarte conradiana Gabb

Astarte rnatthewsoni Gabb

Astarte tuscana Gabb

Avicula fiitida Forbes

Avicula pellucida Gabb

Cardiuin reniondianuin Gabb

Chione varians Gabb

Clisocolus dubius Gabb

Coral liochama orcutti White

Corbula cultriformis Gabb

Corbula traski Gabb

Crassatella loinana Cooper

Ciicullcea bower siana Cooper

Cticullcea decurtata Gabb

■ . n

" 2

■ m

s
s

Lower.

d
3'

* *

rloj

TO
O

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS.

Upper.

Lower.

rr> n
TTO

Pence's
Ranch.

3*
B

K
n

21
a>

Cuctdlcea trjincata Gabb

*
if

*
J*

*
*

s
s

Cyprimeria lens Gabb . .

Dosinia injiata Gabb

Dosinia pertennis Gabb

Dosinia sp

Eriphyla nnibonata Gabb

Exosryra parasitica Gabb

Exozyra sp

Exosyra sp

Goniomya borealis Meek

Gryphcsa vesicularis Lamark

Inocerainus adunca, sp. nov

Inoceramus labiatus Schloth

Inoceramiis multiplicaius ( ? ) Stol

Inoceramus Vancouver ensis Meek

Inoceramus whitneyi Gabb

Lima appressa Gabb

Lima jnicrotis Gabb

Lima shasf ensis Gabb

Limopsis transversa

Lithophagus oviformis Gabb

Lticina postice-radiata Gabb

Lucina subcircularis Gabb

Lutraria truncata Gabb

Mactra ashburneri Gabb

Mactra gabbiana, sp. nov

Martesia clausa Gabb

Meekia navis Gabb

Meekia radiata Gabb

Rleekia sella Gabb

Meretrix arata Gabb

Meretrix longa Gabb

Meretrix nitida Gabb

* \ *

Modiola cylindrica Gabb

Modiola siskiyouensis Gabb

Mytilus pauper cuius Gabb

CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

Mytiliis quadratus Gabb

Nemodon vavcouver'ensis Mkek. .

Niicula solilaria Gabb

Nucula trnncata Gabb

Ostrea sp

Patiopaa concentrica Gabb

Pecten appressa

Pecten californica Gabb

Pecten operculiformis Gabb

Pecten traski Gabb

Pectnnculus pacificus, sp. nov. . . .

Pectiinculus veatchi Gabb

Pholadontya breweri Gabb

P/ioIadoinya anadna, sp. nov

Pinna breweri Gabb

Placosniilia sp

Pleuromya Icevigata Whiteaves.
Protocardium placerensis Gabb .
Protocardimn scitiduin Meek...

Tellina ashburneri Gabb

Tellina decurtata Gabb

Tellina hoffnianni Gabb

Tellina monilifera Gabb

Tellina o'dides Gabb

Tellina paralis Gabb

Terebratella sp

Terebratella obesa Gabb

Thetis annulata Gabb

Trigonia evansaTUi Meek

Trigonia rel. T. evatisafia

Trigonia leana Gabb

Trigonia tryotiiana Gabb

Trapezium carhiatuni

Venus veatchi

Upper.

fro

Waldheimia inibricata Cooper.

I,0\VER.

n
O

rt B

s
s

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS.

Summary of Facts Appearing in the Lists.

Class.

Number of Species

common to

Upper and Lower Chico.

Number of
Species common

to the Chico,
North and South.

Belonging
to the
Lower
Chico.

Belonging
to the
Upper
Chico.

Total
Number.

Cephalopods .

4— (2 doubtful).

12 species.

Gastropods . .

I Some donbtful
1 determinations.

^ Hardy forms

16 species.

Bivalves

17 < or not
( characteristic.

19 species.

Totals

32 species.

47 species.

142

209

An examination of the preceding tabulated lists makes it
apparent that there are two distinct horizons in the Chico
of California and Oregon, each having a fauna to a consid-
erable extent peculiar to itself. A summary of the facts to
be gathered from this list is presented. It will be observed
also that the species belonging to the two divisions are
supplementary rather than similar. In the Lower Chico
there is shown a large number of cephalopods, several of
which are common to both the northern and southern
localities; only two of them, however, are certainly com-
mon to the upper and lower divisions. Similar facts will
be noticed for the other classes. Also, as will be seen
later, very few of the Chico forms are those of the Horse-
town portion of West Coast Cretaceous. Some of the
forms more characteristic for criteria of correlation are
those of the following lists: —

Characteristic Forms of the Chico.
Lower Chico Forms. Upper Chico Forms.

Acanthoceras sp.
Desmoceras hoffnianni
Desnioceras sugatum
Desmoceras ashlandicurn

Baculites chico'ensis
Ancyloceras lineatum
Helicoceras breweri
Helicoceras declive

CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

Upper Chico Forms.

Pachydiscus 7iewberryanus
Schloenbachia chico'insis
Schlcenbachia gahbi
Aiichura fakifonnis
Eripachya pofiderosa
Fulgur hilgardi
Fiilguraria gabbi
Gyrodes expansa
Perissolax brevirostris
Tnrritella chicoensis
Turritella robusta
Tellina sp.
Meekia sp.
Anoviia sp.
Lntraria iritncata
Lucina sp.
Trigonia evansana
Pecfuncuhis veatchi
Venus veatchi

Lower Chico Forms.

Lytoceras sacya
Ly toe eras j acksonense
Lytoceras jukesi
Placenticeras pacifictiin
Placenticeras caltforn icu m
Phylloceras rarnosum
Nautilus sp.
Prionotropis sp.
Scaphites sp.

Schl(£7ibachia oregonensis
Schlcenbachia in nit i cost a
Schloenbachia propinqua
Schloenbachia siskiyouensis
ActcEon pugilis
Actcsonella oviformis
Actceonina californica
ActcBonina pupoides
Antanropsis alveata
Anchura californica
Anchura condoniana
Inoceramus labiatus
Inocerainus xvhitneyi
Lima appressa
Lima microtis
Nemodon vancotiverense
Pecten operculiformis
Pinna breweri
Pleuromya Icsvigata
Protocardium scitulnni
Trigonia rel. T. evansana
Trigonia leana
Thetis aimnlata

Considering, then, the Lower and the Upper Chico, it
will be seen not only that there is a quite noticeable devel-
opment of gastropod and bivalve species in passing from
Lower to Upper, but there is also a large omission of former
species and genera and their replacement by others of
usually different groups. For example, of the many species
of cephalopods found in the Lower division, only four have
been thus far reported from the Upper; and only two with
certainty of identification. Among the gastropods only
eleven have been reported as common to the two horizons
and some of them are likewise doubtful. Others, as Gyrodes
expansa and Cinulia obltqua, are forms that might easily be

Geol.— Vol,. II.] ANDERSON— CRETACEOUS DEPOSITS. 35

mistaken, or at best are not characteristic. One or two
species of Turrttella are found in the Lower Chico, and
four in the Upper, only one of which is common to both.

Among bivalves a greater number of forms is found,
continuing from the earlier to the later deposits; but this is
perhaps to be expected, partly from their more simple habits,
and partly from their greater numbers. But with these also
a critical examination will result in lessening their apparent
importance. Not more than twenty species are shown to
have survived from the earlier to the later Chico, and among
them are Chione varians, Uomomya concentrica, Exogyra
parasitica, Afeekia sella, and perhaps Inoceramus whitneyi,
none of which are of very decisive character. Of the
others, Pecttinculus veatchi, CucuUcea triincata, and T^i-
gonia evansana, while they are more distinctive forms, have
each near allies in the Cretaceous of the West Coast, among
which there has not yet been a close discrimination. Tti-
gonia dawsoni, from the Queen Charlotte Islands, is related
to Trioronia evansana of the Comox beds. There are at
least two varieties of Pectunciilus veatchi, besides a new and
nearly related species, while Cncullcea truncata from the
Chico resembles superficially a Trigonarca from the Queen
Charlotte Islands. One needs to be reassured by careful
comparisons before yielding to first impressions. Nuciila
truncata, if not some of the others, has caused a similar
confusion elsewhere by crossing a well established break
from the Chico to the Tejon, and even into the Miocene,
and ought not to be regarded seriously here.

But the distinction between Upper and Lower Chico
does not appear to need this sort of defense. It could be
properly made even if a much larger number of species
was found to have crossed the interval. It may be true
that a larger number will be found when the localities are
more carefully searched; but even so, future explorations
will probably also increase proportionally the number that
have not crossed the line ; so that it is safe to say the ratio
of species that have survived from the earlier epoch will
not be materially increased.

36 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

If the faunal dissimilarity that is apparent in the Lower
and Upper Chico is to be taken as evidence of a disconti-
nuity in the deposition of this member, it ought also to
appear in deposits outside of the basin of the Sacramento, if
the disturbance extended so far. And when the lists of
Chico species from the different localities are examined
with a view to discovering such evidence, it can only be
said that the fragmentary collections that have been made
at distant points thoughout the Coast Ranges toward the
south are, as a rule, either prevailingly Upper or prevail-
ingly Lower Chico for any given locality. The various
papers by H. W. Fairbanks furnish a number of such lists
that will be found interesting.

Upon the Eagle Ranch in northern San Luis Obispo
County, the Chico beds that immediately overlie the
Aticella-\i^-Ar\x\^ shales have furnished the following spe-
cies: Baculites chico'cnsis, Trigonia evansana {'^),Pectun-
culus veatcht, CticullcBa sp., and Pentacrimts. None of
these species belong exclusively to the Lower Chico, while
some of them have never been found there. Baculites chi-
co'cnsis is, perhaps, peculiar to the Upper division alone.
The Pecluncidus and Pentacrinus are probably undescribed
species. Farther southward, in Santa Barbara County,
a collection from the Sisquoc Canyon consists of the
following: —

Inoceramus sp. Pectunculus veatchi

Baculites chicoensis Meekia sella

Dentaliuin stramineum Cinulia obliqua

Cylichna costata Tellina ashburneri

The same evidence appears in this list as in the preced-
ing, except that more of the species are those of the Upper
Chico alone. Such evidence is, of course, only corroborative,
and does not of itself establish the fact of different epochs
for the Lower and Upper Chico. It shows, however, that
the subsidence that attended or introduced the later portion
of the Chico was not entirely local. Other occurrences of
the Chico are represented in the following lists.

Geol.-Vol. II.] ANDERSON— CRETACEOUS DEPOSITS.

It is not claimed that the Upper and Lower divisions of
the Chico are entirely distinct, but only that there is a
sufficient difference between them to warrant their dis-
crimination.

In widely separated localities both portions of the Chico
seem to be represented together, though perhaps with more
careful study the deposits might be found separable. In
the vicinity of the Bay of San Francisco, four localities
may be mentioned which will be found interesting. The
connections between them are not known, except that they
are not distant from each other geographically. It will be
noticed that in two of these lists, Martinez and Pacheco
Pass, the species are prevailingly those of the Upper Chico,
though at Martinez a species of Trigonia occurs which has
been supposed peculiar to the Lower Chico. In the list
from Curry's, south of Mount Diablo, the species of the
Upper and Lower horizons appear to be about equally
mingled. A little farther south, in the Livermore Valley,
Alameda County, fossils occur that are certainly below the
Upper Chico, if not below the Lower; but this will be dis-
cussed later on.

Pacheco Pass.

Baculjtes chico'ensis Trask
Gyrodes conradiana Gabb
Lhna appressa Gabb
Lutraria truncata Gabb

Meekia sella Gabb
Perissolax brevirostris Gabb
Pharella alta Gabb
Tellina matthewsoni Gabb

Benicia,

ActcBoniyia californica Gabb
Chione varians Gabb
Cucullcea truncata Gabb
Desmoceras jugalis Gabb
Eriphyla tunbo?iata Gabb
Fulgiiraria gabbi White
Globiconcha rei)iondi Gabb
Inoceranius whitneyi Gabb
Lytoceras batesi Trask
Mactra ashburneri Gabb

C4)

Margaritella globosa Gabb

Meekia sella Gabb

PachydiscHS newberryantis Meek

{Ammonites fraternus Gabb)
Pectuncidus veatchi Gabb
Pharella alta Gabb
Trigonia evansana Meek
Trigonia leana Gabb
Turrit ella sp.

November 12, 1902.

CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

South of Mount Diablo.

Acanthoceras tiirtieri White
A7ichiira californica Gabb
Baculites chicoensis Trask
Chio7te varians Gabb
Cucullcea trimcata Garb
Dentalium cooperi Gabb
De?italiuin straniineutn Gabb
Eriphyla timbonata Gabb
Lilt r aria alveata Gabb
Lytoceras baiesi Trask
Mactra tenuisshna Gabb
Meretrix nitida Gabr
Nautilus sp.

Pachydiscus suciaensis Meek
Pec ten operculiforntis Gabb
Pijuia breweri Gabb
Schlutheria diabloetisis, sp. nov.
Scobinella dilleri White
Trigonia cequicostata Gabb
Trigonia evansana Meek

Southwest of Martinez.

Chi one varians Gabb
Cifiulia obliqua Gabb
Corbula cultriforntis Gabb
Cylindrites brevis Gabb
Dentalium cooperi Gabb
Gyrodes expansa Gabb
Gyrodes conradiana Gabb
? Helicoceras verviictdare Gabb
Meekia sella Gabb
Meckia navis Gabb
Meretrix arata Gabb
Mytilus pauperculus Gabb
Nucula truncata Gabb
Pachydtsctis sp.
Pecten tnartinezensis Gabb
Perissolax brevirostris Gabb
Pectunculus veatchi Gabb
Pugnellus hamulus Gabb
Solarium inortiatum Gabb
Tellina crqualis (? ) Gabb
Tellina hoffmajini Gabb

List of Fossil Species from Todos Santos Bay, Lower California.

Act(Zonina pupoides Gabb
Ancyloceras lineatum Gabb
Astarte matthewsoni Gabb
Bactilites chicoensis (?) Trask
Cerithiu)n pilingi White

Ledo translucida Gabb
Lunatia avellana Gabb
Mactra ashburneri Gabb
Nerita sp.
Nucula truncata Gabb

Cerithiuin totium-saiictorum White Ostrea sp.

Chione varians Gabb Pectunculus veatchi Gabb

Cinulia obliqua Gabb Pugnellus sp.

Coralliochama orcutti White Tellitia cequalis Gabb

Fulguraria gabbi'SSYWX'E. Tellina doides Gabb

Fusus sp. Trochus eurystomus White

Gyrodes expansa Gabb Turritella chicoensis Gabb

The horizon of Todos Santos Bay in Lower California is
evidently that of the Lower Chico, and is supplementary to
those of Orange and Los Angeles counties already given.
Special weight has been attached by White, Stanton, and
others to the occurrence of Coralliocha7na orcutti, and these
beds have been generally correlated with those of Wallala,
on the coast of Mendocino Count}'-, and with the lowermost
Chico of the Sacramento Valley. At Wallala, Coi'alliockama
occurs with Solarium ivallala'ense White, Ostrea, Inocer-
amtis, Pecten, Cylichna, and Turritella.

Gkol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 39

It appears that the disturbances of the West Coast have
been to some extent local, though probably synchronous
during the Chico epoch. Further evidence of this is also
found in the deposits of Southern Oregon and Siskiyou
County, California, where the fauna seems to indicate for
these localities a different basin. The Oregon Basin was
probably not directly connected with that of the Sacra-
mento, at least until during the later Chico. Species that
belong characteristically to the upper horizon are found
plentifully common in the two basins, while in the lower
horizon they are essentially different. There is a closer
relationship between the deposits of Southern Oregon and
Vancouver Island than between those of the latter and of
the Sacramento Valley. There is also a representation of
Upper Missouri — Colorado — forms in the fauna of Southern
Oregon, as will be seen in the species of Inoceramus and
Scaphites, and in some of the ammonites.

The cephalopods of these lists form one of the most
striking features. The numerous species of Schloenhachia^
alone, almost distinguish this basin from others of the
Pacific Coast; while to these may be added six species of
Scaf kites, two species of Acanthoceras, two of Lytoceras,
besides the aberrant forms, including Hamites, Helicoceras,
and Heteroceras.

The Phoenix locality is regarded as representing strati-
graphically the Lower Chico horizon of the Sacramento,
yet the differences of the faunas are considerable.

Attention is also called to the occurrence in the Oregon
Basin of such forms as Desmoco'as siigaUim, Scaphites
gillisi, Scaphitcs klamathensis, Goniomya borealis, and P}'o-
tocardmrn scituluni. Many others will also be noticed that
seem to have special importance; these will be mentioned
under the heading of correlation.

While there are fewer species of cephalopods that con-
nect these beds directly with those of the Lower Chico in
the Sacramento Valley, the large number of cephalopods,

' In the sumrner of iSgg, Dr. J. P. Smith discovered in the Lower Chico of Silverado
Canyon, Orange County, California, Schlaenbachia oresorunsis and others of this genus like
those of the Oregon Basin.

40 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 30 Ser.

and especially the two species of Acanthoceras, the Lytoc-
eras species, and others may be taken as evidence of
a rather low position in the Chico. Moreover, beds of the
same or of a little later age at Jacksonville, only a few
miles to the west, contain Lower Chico forms, such as
Trigonia cequicostata, T. leana, Pecten operctilifortms,'e\.c.,
which have not been found above the Lower Chico. Nor
is there a single species among this collection that is char-
acteristic of even the uppermost Horsetown beds.

The horizon of the Phoenix beds is almost identical with
that of Cottonwood Creek and Shasta Valley, in Siskiyou
County. Near the town of Hornbrook (Henley) the Cre-
taceous beds have a thickness approaching 2,500 feet, the
lower two-thirds of which is fossiliferous. There are two
well marked horizons, the lower one containing an abund-
ance of trigonias and other bivalves and gasteropods, and the
upper one containing a comparatively large number of ceph-
alopods, among which are two species of Placenticeras, two of
Desmoceras, a Pachydiscns, and two species of PhyUocei'as.
On Willow Creek, a few miles south of the Klamath River,
and in the strike of the Henley beds, the same horizons occur
in the same relation. Here the upper zone contains also
Pachydiscns newberryanus, Desmoceras hoffmanni, Prionotro-
pts crenulatuni, Scaphites condoni, Hainites artnattini, Des-
moceras sp., and many others of a Lower Chico aspect.

The Horsetown Epoch.

An examination of the Horsetown fauna shows it to con-
sist in large part of abundant species of cephalopods, espec-
ially of the genera Desmoceras and Lytoceras ; their relatives,
Hoflites and Acanthoceras are also common; and there
are, perhaps, three or four species of Phylloceras, one or
two of Olcostephamis, at least two species of Nautilus, and
two of Belemnites. One-half of the entire fauna of the
Horsetown belongs to the class of cephalopods, and this pro-
portion seems to be fairly constant throughout. Probably
when the fauna of the Horsetown strata becomes more per-
fectly known, the proportion of cephalopods among the

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS.

whole will be increased still more. In the basin of the
Great Valley they are especially abundant and varied, some
of them reaching very large dimensions. Among the very
large forms are Lytoceras argonaiitarmn and Ancyloceras
^ercostatum. The following is a partial list of those already
known from the Horsetown beds of the upper Sacramento
Valley: —

List of Fossil Species from Horsetown Beds.

Acanthoceras dispar (?) (d'Orb.) Stol.
AdcBon impressus Gabb
Anchiira sp.

Ancyloceras lineatum Gabb
Ancyloceras remondi Gabb
Anisoniyon meeki Gabb
Archoinya undidata Gabb
Avicula mucronata Meek
Avicula whiteavesi Stanton
Belemtiites impressus Gabb
Beleimntes sp.
Chiotie varians Gabb
Crioceras latum Gabb
Crioceras percostatum, Gabb
Cucullcza truncata Gabb
Cumlia sp.

Desmoceras betcdanti Brong.
Desmoceras breweri Gabb
Desmoceras colusaense, sp. nov.
Desmoceras dilleri, sp. nov.
Desmoceras haydeni Gabb
Desmoceras hoffmanni Gabb
Desmoceras lecontei, sp. nov.
Desmoceras merriami, sp. nov.
Desmoceras subquadratum, sp. nov.
Desmoceras voyi, sp. nov.
Diptychoceras Iceve Gabb
Douz'illiceras mamillare Schloth.
Eriphyla sp.

Eripachya hoffmanni Gabb
Eripachya perforata Gabb
Exogyra parasitica Gabb
Fusus aratus Gabb
Hehcancylus cequicostatus Gabb
Helicaidax bicaritiata Gabb
Holcodiscus re\.H. theobaldianus Sioi.
Hoplites remofidi Gabb
Inoceramus sp.
Lima microtis Gabb
Lima shastensis Gabb

Liocium punctatum Gabb
Lunatia avellajta Gabb
Lytoceras angtilatum, sp. nov.
Lytoceras argonautaru)n, sp. nov.
Lytoceras batesi Trask.
Lytoceras sacya Forbes
Lytoceras x^. L. sacya
Lytoceras timotheanum May.
Meekia sella Gabb
Nautilus gabbi, sp. nov.
Nautilus suciaensis, sp. nov.
Neithea grandicosta Gabb
Nemodon vancouverense Meek
Nerinea dispar Gabb
Nerinea maudensis Whiteaves
Nerita deformis Gabb
Olcostephattus traski Gabb
Olcostephanus sp.
Ostrea sp.

Oxytoma mucronata Whiteaves
Pachydiscus sacramenticus, sp. nov.
Pecten opercidiforjnis Gabb
Pinna sp.

Pleuromya IcBvigata Whiteaves
Pleuromya papyracea Gabb
Plicatula varia Gabb
Phylloceras onoense Stanton
Phylloceras shastalense, sp. nov.
Potamides diadema Gabb
Ptiloteuthis foliatus Gabb
Ringinella polita Gabb
Scalaria albensis (?) d'Orb.
Schlcenbachia inflata Sowerbv.
Sonnertia stantoni, sp. nov.
Thetis elofigata Gabb
, Trigonia czqicicostata Gabb
Trigofda evansana Meek
Trigonia rel. T. evansana Stanton
Trigonia leana Gabb
Turnus plenus Gabb

42 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 30 Ser.

Among the gasteropods of the Horsetown which may be
mentioned are species of Nerinea, RingincUa, Actaon,
Anchu?'a, and Helicaulax. Bivalves are represented by
such forms as Avicula, Plciiromya and Lima, two species
each, along with others, as Plicatula varia and Thelis clon-
gata. The following also are typical Horsetown spe-
cies: Crioceras latum, C . percostatiim, Diftychoceras Icbvc,
Schlocnhachia injlata, Liociiim ^unctatiim, Potamidcs dia-
denia (?), Oxytoina imicronata, Ai'chomya undtdata and
Mithea grandicosta. More than eighty species in all are at
present known, though it is quite probable that this is not a
large part of what will be known when the beds are more
carefully searched.

The Horsetown fauna in its most typical development is
of a tropical character, as has already been noticed by sev-
eral writers. Many of its congeners are numerous in the
fauna of Southern India. Both have evidently come essen-
tially from the same source. The southern aspect of the
Horsetown is seen in the numerous species of Lytoceras,
Phylloceras, and many of the crioceran and nautilian
forms. In this respect it contrasts strongly with the
northern aspect of the fauna preceding it, in the upper
portion of the Knoxville.

Comparatively few of the gasteropods and bivalve species
occurring in this list continue above the Horsetown, though
some have allies even in the Upper Chico. Probably when
the Horsetown fauna becomes more completely known the
transitional forms will appear even less significant, since the
cephalopods form its ruling class. Perhaps, also, it will be
possible to separate it into subdivisions, better characterized
than those of the Chico. Diller and Stanton (1894, P- 445)
mention as belonging to its upper portion only, Lytoceras
sacya, Desmoceras beiidanti, Schlcenhachia injlata, Acanthoc-
eras mamillarc and a few other forms. Likewise there are
a few that belong especially to the lower portion of the
Horsetown, among which are Belemnites impresses, Crioc-
eras percostatiim, Olcostephaniis traski, and perhaps Heli-
caulax hicarinata and Potamidcs diadema. On the other

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 43

hand, many important species run through the whole of the
Horsetown, forming connecting Hnks from bottom to top.

In the basin of the Sacramento the base of the -Horse-
town division of the Cretaceous has perhaps been well
placed at the upper limit of the range of Aucella. Few if
any of the species characteristic of the Horsetown appear
to extend below this limit, and until this supposition shall be
proved erroneous the boundary seems to be a practical one.
It is stated by Diller and Stanton (1894, p. 446) that many
well known and typical Horsetown species occur within a
few hundred feet, stratigraphically, of the upper range of
Aucella, near the Elder Creek section. Below this point,
however, as one descends the series, they entirely disappear
or have not been found. Or, with the exception of Belem-
nites impressus, Lytoceras batesi, Crioceras latum, and two
or three others, there are perhaps no species connecting the
Horsetown faunally with the strata containing Aucella,
while on the other hand, the associates of this genus form a
separate and distinct fauna.

The Pa sk cut a Hoi'izon.

The strata containing Aucella, that is, Knoxville, as
originally understood, have been made the subject of a
special faunal study by Dr. Stanton (1895) who has pub-
lished a somewhat complete list, containing in all about
seventy-seven species, fifty of which are described as
new. He remarks that the majority of this number are
rare; yet even so, this is an unexpectedly large number
when contrasted with the few species that had formerly
been known from the Knoxville. Yet had this assemblage
of species been found distributed throughout the twenty
thousand feet of strata that have been referred to the
Knoxville, it would not have seemed surprising, for this
thickness of strata is twice as great as the entire sum of the
Horsetown and Chico strata combined. But the most inter-
esting part of this discovery is not the large number of
Knoxville species brought to light, but the fact that they
were nearly all obtained, not from the entire range of twenty

44 CALIFORNIA ACADEMY OF SCIENCES. [Proc. .^d Ser.

thousand feet of what was termed Knoxville strata, but from
the uppermost four thousand feet of them. The seventy-
seven species enumerated, all of which, with the exception
of two or three species of Aucella, are apparently confined
to this relatively small stratigraphical range, are almost
equal in number to the eighty or more species that are thus
far known from the six thousand feet of Horsetown strata,
where the individuals are far more abundant. In fact, the
actual thickness of strata through which this new and distinct
fauna ranges is not yet definitely known, though from the
statements made in regard to the locality and position of the
different species, we learn that the great majority of them
have been found in or near the sections studied in the
Sacramento Valley, and that the stratigraphical range is
rarely if ever given as greater than three thousand feet
below the upper limit of the Aucella range. With the
introduction of this new fauna at that horizon the Atccellcs
gradually diminish, until at the next immigration of species
they entirely disappear. Stanton says of this fauna: ''All
but seven of the species are mollusca, including thirty-three
species of Pelecypoda, one species of Scaphopoda, eighteen
species of Gasteropoda, and eighteen species of Cephalo-
poda, of which fifteen are Ammonoids, and three are
Belemnites. The other seven species include five Brachio-
pods and two Echinoderms." So far as known, the cephalo-
pods contain a single species each of Dcsmoceras, Lytoceras,
and Phylloccras, forms which are so numerous in the Horse-
town, while Hoplites is represented by five species and
Perisphmctes by one.

The two species of Olcostephanus are both new and have
not been found in the Horsetown. An important feature of
the Gasteropoda is the large number of Turbo species, six
species of this shell being described. Two species of
Hypstpleu7-a, and three of Cerithium are known. Nothing
particularly characteristic is to be noticed with reference to
the bivalves, most of which, with the exception of Aucella,
have allies among the fauna of the Horsetown. The
Brachiopoda, however, deserve mention, the five species
being, perhaps, peculiar to this fauna alone.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 45

The fauna here described is especially well represented
in the vicinity of Paskenta, Tehama County, where a few
localities have yielded most of the described species. Other
localities that have furnished a number of the species which
have been included in this list appear to belong to the same
horizon. One is a locality of white limestone along Sulphur
Creek, Colusa County, from which the following species
have been obtained : RhynchoneUa whitneyi, Modiola major,
Pecten coniplextcosta, Lucina coliisa'ensis, Atresius Ih-attis,
and Turbo cohisaensis. Other species from evidently the
same horizon in the near neighborhood may be added, as
Astarte trapezoidalis, Turbo morganensis, and Turbo
zvilburensis.

The exact position of this limestone in the series of
AuceUa-\)^2iXm^ strata has not been determined, but it
appears to be interstratified with shales containing Aucella;
and since many of the same species have been found near
Paskenta, in thin layers and lenses of limestone, it seems
pretty evident that the same horizon is represented in both
localities, and that the strata of both belong near the top of
the upward range of Aucella.

Southward of the Sacramento Valley scattered occur-
rences of yl?^c^//rt-bearing rocks are found of which but
little is yet known. One mile north of Berkeley, Alameda
County, Aucella and Belemnites have been found in dark,
sandy shales, and near by is a bed of light colored lime-
stone having a fetid odor, from which Dr. J. C. Merriam
and Charles Palache obtained Modiola major, Lucina cohi-
saensis, Pcctcn complexicosta, Cardinia (?), Myoconcha (?),
Turbo, Atresius liralus, and other forms resembling Pas-
kenta species. At the eastern edge of the town, almost in
the strike of these rocks, are sandy beds that will be
referred to again, and which Dr. Merriam regards as
undoubtedly of Chico age.

Farther south, in the vicinity of Haywards, fossiliferous
shales occur from which was obtained a specimen of Crioc-
eras -percostatum, which is now in the collection of the
California Academy of Sciences. This locality is classed
as probably of the Knoxville (Paskenta) epoch.

46 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

In the Alum Rock canyon, a few miles east of San Jose,
Dr. J. P. Smith has found Ancella fiochi associated with
Beleinnites; and in the canyon of Stephens Creek, a few
miles west of the same town, he has reported a similar bed
of dark, siliceous shale containing Ancella fiochi.

Still farther south, near Gilroy, on the road from San
Jose to Santa Cruz, Ancella crassicollis has been found by
Dr. Smith and others, along with an Olcostepkanus, and
other undetermined species.

The most southern locality in which Ancella has yet
been discovered in California is a few miles north of San
Luis Obispo. Dark, Ancella-heanng shales occur in the
hills to the west of Santa Margarita, where in one exposure
of them on the Eagle Ranch the slender form of Ancella
piochi is very abundant. An ammonite, probably an Hop-
lites, was also obtained at this locality.

While not exactly demonstrable from our present knowl-
edge, it yet seems evident that a more or less connected
line of deposits of Knoxville (Paskenta) age can be traced
along the eastern border of the basin of San Francisco Bay
from beyond San Jose northward. This line of deposits
will be be seen to include Gilroy, Alum Rock, Haywards,
and the exposures near Berkeley. The topography of the
country suggests also that it might even be extended by a
little exploration to connect with deposits of the same age in
Napa Valley, at Sulphur Creek, and even to Knoxville itself.

One other isolated locality deserves to be mentioned;
that upon the northern flank of Mount Diablo. Mr. Turner
discovered here Ancella-hearmg shales in contact with
metamorphic rocks of a still older series. The fauna of
these shales consists of Ancella which he refers to the type,
A. mosqnensis, Bclcmnites, Inoccramns, and a few species
of gasteropods.

It has already been noticed that in the strata referred to the
Paskenta horizon beds and lenses of limestone are common ;
and as usual, according to Turner, here, too, all the fossils
with the exception of Ancella are found in layers of lime-
stone. It seems most probable, therefore, from the foregoing

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 47

statements, that all of these scattered localities contain
strata entirely equivalent to that of Paskenta, since below
this horizon in the sections of the Sacramento Valley no
ammonites have thus far been discovered. This horizon,
moreover, represents exactly and completely all that should
be included in the Knoxville as it w^as first described by
White (18S5).

Three things should be noticed regarding the Knoxville
horizon as thus understood, showing its faunal relations to
that of the Horsetown, First, it is characterized by an
almost distinct fauna, very few species of which appear to
have been found in the Horsetown portion of the series,
while in each the total number of species is rather large.
Second, the typical and varied Horsetown fauna occurs
very near, though above, the upward limit of the Knoxville,
and appears there in a somewhat striking contrast with it.
The transition is sudden. Third, the Horsetown fauna,
with the exception of three or four species already men-
tioned, does not seem to have been, and hardly could have
been derived from that of the Knoxville. The types are
entirely different. Dr. White believed the Knoxville fauna
to be decidedly boreal in character, and referred particu-
larly to the genus Aticella in support of this view. The
same opinion has been held by others, and Dr. J. P. Smith
states that some of the ammonites have their nearest alHes
in the north of Europe. Reference has already been made
to the equally manifest tropical aspect of the fauna of the
Horsetown.

Another circumstance that appears to coincide with this
faunal demarcation, and which forms a strong corrobora-
tive testimony in support of the conclusions to be drawn
therefrom, will be discussed later in connection with the
distribution of the Horsetown beds and the general occur-
rences of intrusive peridotites.

The Sub-Knoxville Horizon.

One of the most important contributions made by Diller
and Stanton to our knowledge of West Coast geology was
in the discovery of an immense thickness of strata below the

48 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

horizon of the true Knoxville, which for lack of a better
name is here designated as the sub-Knoxville. Below the
Knoxville (Paskenta) horizon in the Tehama and Shasta
sections there are at least 15,000 feet of conformable strata
from which but few organic remains other \}i\2Ln Aucella have
been obtained. It is not yet possible to say where the exact
limits between this and the Knoxville horizon may be drawn,
and indeed it may not be possible to establish one more than
theoretically in these sections. Still there appears to be
quite sufficient evidence thatthe Knoxville, as here restricted,
was inaugurated by some profound movements, felt else-
where, if not in this basin itself.

The sub-Knoxville horizon, that here forms at least one-
half of the entire conformable series, has not yet been
clearly recognized outside of the Sacramento Valley, either
in California or Oregon. Nearly, if not quite all the occur-
rences of Aucel/a-hQaring rocks in the Coast Ranges have
shown themselves by their fossil remains, other than
Auce//a, to belong wholly to the Knoxville (Paskenta)
horizon, and have not been shown to exceed it either in
thickness of strata or in faunal contents. If the sub-Knox-
ville horizon has really any equivalent in other portions of
the State, they ought to be found outside of the borders of
the Great Valley, beyond the margins of recognized Cre-
taceous deposits; and it is not unlikely that some of the
stratified rocks of the Klamath Mountains will prove to be
their complete contemporaries.

VI. Disturbances of the Period.
I. Distribution of the Horsetown Beds.

In dealing with the two horizons of the Chico an attempt
was made to show the wide-spread disturbance that had
intervened and which was locally accentuated. The evi-
dence for this was first a considerable faunal change in
passing from Lower to Upper Chico, and second a general
lack of coincidence in the distribution of Upper and Lower

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 49

Chico deposits. It might also be said that the Lower Chico
has a wider transgressional expansion than the other.

Quite similar relations exist also between strata of the
Lower Chico and Horsetown epochs, with the difference,
however, that in California the Horsetown is but little known
outside of the Sacramento Valley, or to express it more
accurately, outside of the immediate borders of the Great
Valley. Its distribution is apparently restricted, just as are
the deposits of the sub-Knoxville, almost entirely to this
basin, where it builds with the strata of the lower and upper
horizons of the Cretaceous a more or less continuous series.
The fact is a remarkable one, that throughout the Coast
Ranges west and south of the Great Valley, few if any
deposits of Horsetown age are found. Those that have
been satisfactorily shown to belong to this epoch lie upon
the immediate borders of the Great Valley, and they have
yet to be found south of the latitude of Benicia and the
junction of the two great rivers of this basin.

There is no assignable reason why deposits of the Horse-
town should not be found within the boundaries of the San
Joaquin Valley, but as yet the nearest approach to this fauna
that has been discovered south of the latitude named is from
a locality lying about eight miles east of the town of Liver-
more, at Arroyo del Valle, some miles southeast of Mount
Diablo. This is a locality discovered many years ago by
Dr. Lorenzo G. Yates of Santa Barbara, who obtained
from this place a large number of ammonites now in the
collections of Stanford University. Among them are the
following species as determined by Dr. J. P. Smith: —

Baculites chico'ensts Lytoceras cf. L. tinwtheaniim

Belemnites sp. Pachydiscus cf. P. newberryayius

Cinulia obliqua Pachydiscus cf. P. suciaensis

Desmoceras hoffmanni Phylloceras onoense

Desmoceras cf. D. selwynanimi Phylloceras raniosiini

Hoplites remoiidi Placenticeras californicuni, sp. nov.

Lytoceras alamedense Placenticeras pacificmn
Lytoceras batesi

It can not be denied that the fauna of this locality shows
a strong intermingling of Horsetown and Lower Chico

50 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

species. In this respect it resembles other locaHties within
the borders of the Great Valley. The succession of disturb-
ances inaugurating the Chico was here so little felt as to
allow pre-existing species to survive locally. The Chico
faceies of this locality, is, however, represented by such
forms as Pachydiscus newberryanus., P. suciaensis, Baculites
chico'ensis, Cinulia obliqtia, and also Placenticeras califor-
niaini and P. facijicwn have been found elsewhere in
undoubted Chico deposits, and they have been found in no
other deposits. The former occurs in the Lower Chico
beds of the Forty-nine Mine, Jackson County, Oregon, and
in exactly the same horizon at Henley, Siskiyou County,
California, along with P. pacificum; while Dr. J. P. Smith
states that P. californicum has been found in the Lower
Chico of the San Fernando Mountains, Los Angeles
County, California, and that Mr. F. Rolfe has found in
the Lower Chico of Silverado Canyon, Orange County,
California, P. pacijiacni associated with typical fossils of
this epoch.

2. The Chico-Knoxville Unconformity.

This occurrence of Lower Chico strata seems the more
important because upon the northern flanks of Mount
Diablo, only a few miles away, Chico beds are found
apparently conformable upon AucclIa-hediYmg shales form-
ing a series of several thousand feet in thickness. These
Mount Diablo deposits were first described by H. W. Tur-
ner (1891) and afterward discussed by Stanton (1895,
p. 21, etc.). Mr. Turner believed that a portion of this
conformable series represented the Horsetown, but was
unable to prove it to his own satisfaction. The upper por-
tion of the series has yielded Baculites chicoensis and a few
other Chico forms, and the lower portion is the horizon of
the Knoxville discussed a few pages back. Stanton esti-
mated that the intervening strata had a thickness of about
five thousand feet, in regard to which he says: "If the
horizons are all represented, then sedimentation was here
very much less rapid during a part of the Cretaceous

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 5 1

than it was one hundred and fifty miles north, in
Tehama County; while if the Horsetown and a part of
the Knoxville beds are really lacking, there must have been
a local uplift in the Mount Diablo region which did not
involve the Coast Ranges farther north." The Chico beds
are here the Upper Chico and much of the five thousand
feet of strata intervening between this and the Aucel/a beds
must evidently belong to the Chico group, since on the
south side of the mountain the Lower Chico occurs. One
is forced, then, to accept Mr. Stanton's second alternative,
with the amendment, however, that the uplift, while local,
was only a local accentuation of a disturbing influence much
more general throughout the Coast region.

It will be interesting to remember here the cases of un-
conformity discovered by Fairbanks (1895, p. 426, etc.)
between Chico and Knoxville beds in San Luis Obispo
County, in reference to which he says: "The Knoxville
(Paskenta) is bordered on the west by a great dike of ser-
pentine, while on the east a nearly hidden axis belonging to
the Golden Gate (Franciscan) series projects through it in
numerous places. The Knoxville presents a very much
disturbed condition, partly due to the dikes of serpentine.
The Chico, consisting almost wholly of heavy bedded sand-
stone, rises on the eastern slope, overlapping the Knoxville
shales and capping portions of the first line of hills."
Points at which this unconformity is particularly clear he
has discussed more in detail. One was found upon the
Eagle Ranch, west of Santa Margarita, and another a
few miles to the northwest, where almost undisturbed
Chico sandstones rest upon highly tilted Knoxville shales
with Aticella fiochi. Concerning this region Dr. Fair-
banks (1898, p. 560) says in a later paper, speaking of the
Chico: " Fossils are not abundant but they were found
in sufficient numbers in the Santa Lucia Mountains to
demonstrate the age of the formation. In the latter locality
the sandstone terminates downward in a conglomerate which
is in places one hundred feet thick, resting either upon the
Knoxville shales or the Golden Gate series. The relation

52 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

to the Knoxville shales was carefully examined at many
points along the northern slope of the Santa Lucia Moun-
tains and a conclusion was reached which is in accord with
one already published, namel}^ that the Lower and Upper
Cretaceous are, in this region at least, separated by an
unconformity. This is shown by a marked discordance in
the dip between the two and the extension of the upper
across the strike of the lower, etc," The Chico here
described is that of the upper horizon as previously shown.
And what has been so clearly demonstrated in the region
south of the Great Valley is exactly paralleled beyond its
boundaries northward in California.

In a former paragraph mention was made of AuccIIa beds
occurring at the base of the Cretaceous section in the Sis-
kiyou Mountains, In the collections of the State Mining
Bureau in San Francisco is a specimen of calcareous rock
about two pounds in weight, consisting of a compacted mass
of AiLceUa fiochi shells, and bearing upon its label, " from
Siskiyou County, California." Miss M. Hearn of Yreka,
from whom this specimen was obtained, states that it came
from the south side of the Siskiyou Mountains, and from a
locality from which many Chico fossils have often been
collected, and one which is included in the preceding lists
of Chico fossils from that region. Much of the Cretaceous
series along Cottonwood Creek, Siskiyou County, has the
appearance of the soft clay shales of the Knoxville beds on
Cottonwood Creek, Shasta County; and to one familiar
with these shales, and with the unconformity between Chico
and Knoxville found far southward, it is not surprising that
Aucella beds should be found here also unconformably
related to the Chico. How extensive this unconformable
relation may be throughout the coast region is not yet
known; but from the observations of Dr. J. C. Merriam
(1901) in the basin of the John Da}'^ River, it appears to
have a wide range in the Oregon Cretaceous basin. He
says: " In the valley of Bridge Creek a great thickness of
conglomerates, sandstones and shales is exposed at Mitchell,
eighteen miles northwest of Spanish Gulch. The upper

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 53

portion of this section much resembles the Cretaceous at
Spanish Gulch, while the lower part, consisting of soft dark
shales with an occasional thin, hard stratum, is an exact
duplicate of the Knoxville, as it is usually developed in
California and Southern Oregon. The total thickness of
the section is hardly less than 3,500 to 4,000 feet, of which
the shales probably make up more than one-half. At the
lower end of the Mitchell Knoxville section the shales dip
westerly for a short distance, but the west side of the anti-
cline is covered by Tertiary formations." The fossils of
the upper portion of the section show it to be of Lower
Chico age.

3. The Peridotite Intrusions.

The relations of the serpentines of the Coast Ranges to
both the Knoxville (Paskenta) and the Chico strata form
another convincing proof of the unconformity of the Chico
upon the former. It is well known that the peridotites
from which the serpentines have been derived have been
intruded into the Knoxville beds at many places in the
Coast Ranges, and that this has happened especially, also,
throughout the very region from which the Horsetown
strata are entirely missing. A few of these cases may be
given, though an extended and complete list of them, that
have from time to time been noticed, would be superfluous
for the purpose of this paper.

On the map of the Great Western Quicksilver Mine,
Napa County, published by Becker (1888, p. 358), tongues
of serpentine are shown penetrating the " Neocomian"
shales. Such occurrences are said to be abundant, and so
closely and generally are serpentine and Knoxville shales
associated in that region as to suggest to Becker the deri-
vation of the serpentine from sedimentary rocks. He
(Becker, 1888, p. 121) says: "Highly inclined strata
strike into serpentine areas in such a manner as to wholly
preclude the supposition that the serpentine represents an
earlier mass." At Mount Diablo, also, Mr. Turner (1891)
has shown similar dikes of serpentine cutting the Knoxville

(5) November 24, 1902

54 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

shales. In Tehama County, the shales are said to dip
steeply away from a mass of serpentine at their base, which
has evidently been a disturbing agent. H. W. Fairbanks
has repeatedly spoken of serpentine cutting the Knoxville
shales in the southern Coast Ranges, as near San Luis
Obispo and other neighboring points. Dr. J. P. Smith
states that he has observed serpentine intrusive in the
Aucc/Za-heanng shales on the Whitney ranch, some miles
southwest of Gilro}^ Santa Clara County.

Exactly similar relations are found in connection with
strata of the same age at Riddles, Oregon, where a belt of
Cretaceous rocks five miles in length is bordered on the
west by serpentine and peridotite. It is thus seen that
from San Luis Obispo County northward far into Oregon
the Knoxville is everywhere penetrated and disturbed by
dikes and masses of serpentine and accompanying perido-
tites; and it is exactly from this Coast Range region in
which serpentine is common that the Horsetown strata are
entirely absent. (Turner, 1891, map opposite p. 383.)

At many places in this same region Chico beds are also
found in contact with the serpentine; but it has not been
stated that they have ever shown evidences of having
been even slightly altered or disturbed by the peridotites.
Indeed, quite the contrary is usually the case, as Fairbanks
has already stated.

4. The Chico Overlap.

This serpentine intruded country does not form a narrow
strip bordering the basin of the Great Valley, but it extends
from that basin westward, frequently to the ocean. It is
many miles in width, and extends from the southern portion
of California northward far into Oregon. In the latitude
of southern Mendocino County this intrusion has thrown
the Horsetown entirely out of the series in the Coast
Ranges west of the Great Valley, while Chico strata are
found upon both sides of the peridotite belt, at Wallala,
upon the seaboard and in the Sacramento Valley. The
position of these Wallala beds, which have been classed as

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 55

Lower Chico, lying as they do near the low coastal border
of a large area of Knoxville which has been uplifted by this
intrusion, accords well with the unconformity which else-
where exists between them.

On the other hand, the Chico beds, representing the
great overlap succeeding these intrusions, are known in
many cases to rest directly upon masses of serpentine in
an undisturbed position. This is particularly true in north-
ern California. Near Yreka, Siskiyou County, a belt of
serpentine and peridotite crosses the country in a south-
westerly direction, passing beneath the town. At a dis-
tance of one to three miles on either side of the town are
to be seen the fossiliferous and unaltered beds of the
Lower Chico, resting in nearly a horizontal position upon
the serpentine. Other similar occurrences have also been
noticed. South of Weaverville, in Trinity County, the
Lower Chico occurs, and appears to have some similar
relation to the serpentines lying to the north. Similar facts
have also been noticed in the southern Coast Ranges.

Thus every class of evidence required to fully demonstrate
the post-Knoxville disturbance seems to have been satisfac-
torily shown to exist. Not only have the Chico deposits
been found resting unconformably upon the Knoxville, but
the Horsetown is evidently absent from wide regions in
which both of the other members occur; and at the same
time copious masses of eruptive rocks are found exactly in
the position to coincide with the intervening disturbance and
accordingly with the unconformity between them ; and it
has also been shown that beds of the Lower Chico rest in
an undisturbed position directly upon areas of the same
intrusion.

Vn. Correlation of Deposits.

Without attempting to settle the difficult problems of
correlation, there are a few observations that may be made
relative to results that are not beyond the range of data
already known. For distant and unrelated provinces pos-
sibly no correlation will ever be attained that is entirely
satisfactory; and that is not the aim of this paper.

56 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

1. The Sacramento Sections.

The Sacramento sections, on account of their complete-
ness and simple stratigraphic succession may well become
standards of great value for the correlation of other Creta-
ceous deposits of the greater Pacific province ; but only
when they themselves become very much better known.
For the present, criteria must be sought by means of which
these sections may be studied. It is evident, too, that the
greater stratigraphic range of species in this basin will
always be a perplexing element in using any of these
sections as a standard for comparison. For that reason,
the plan of selecting deposits beyond the limits of this
basin, in which there are clear evidences of disturbance,
has here been attempted.

For the Chico epoch this method is reasonably satisfac-
tory, and with our increasing knowledge of the Cretaceous
deposits of the Pacific Coast, it will become more so. Pos-
sibly when the Horsetown faunas of California and Oregon
become better known the same method will be found
equally applicable.

In correlating widely separated deposits by purely
paleontological means, the safest conclusions are reached
by considering whole faunas, or the ruling classes, and
supplementing such evidence by the more direct comparison
of species, some of which have a wide geographical range.

It is a surprising fact that the cephalopod faunas of the
Pacific Coast basins of America are not more closely
related, while some of them have comparatively strong
affinities with those upon the opposite side of the Pacific,
namely, of eastern and southern Asia. Already there are
many species known, either identically or representatively
common to the Cretaceous of Southern India, and to one or
more of the basins of the Pacific Coast of America; and
the same is true of the Cretaceous deposits of Japan.

2. Equivalents of the Chico.

It has been the custom of most writers upon the subject
to regard the Upper Cretaceous rocks of Vancouver and
the neighboring islands as homotaxial equivalents of the

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 57

Chico of California. Mr. J. F. Whiteaves (1876-84, p. 179)
has published an extended list of species from the fossilifer-
ous beds of the Nanaimo and Comox sections, in which he
indicates the horizon of each, and its occurrence, when
known, in the Chico beds of the Sacramento Valley.

Of the fifteen species of cephalopods occurring in these
lists, only three are known to occur also in the Chico.
Nearly one-half of the gasteropods and almost the same
proportion of the lamelHbranchs are abundant or common
in the Chico of California. The occurrence of the inter-
esting species, Inoceramus labiatiis, in the Lower Chico of
California, and in "Division ^" of the Queen Charlotte
Islands section, perhaps shows the equivalence not only
of these horizons, but also indirectly the equivalence of the
Nanaimo beds, and the uppermost beds of Queen Charlotte
Islands. It is an unusually interesting point, and one that
can furthermore be considerably strengthened by evidence
that is not quite so direct but entirely conclusive. It serves
also to correlate more satisfactorily the deposits of the
Pacific border with those of the interior basin.

Inoceramus labiatus is abundant in the upper portion of
the Colorado group, but is rare outside of that horizon. In
the deposits of the Pacific border it is apparently confined
to the Lower Chico and to beds homotaxially equivalent.

The upper beds of the Oregon Basin, including those that
have been referred to as the Phoenix and Henley beds, hav-
ing a stratigraphic position equivalent to that of the Chico,
contain not only Inoceramus labiatus, but also other forms
still more trustworthy for purposes of correlation.

In the three basins, therefore, of the West Coast, the
Chico, the Nanaimo, and the Phoenix and Henley beds may
be shown to be homotaxially equivalent, and equivalent also
to the beds of the Colorado group in the interior basin.

The faunal elements that appear to connect these hori-
zons in the Pacific border basins contain not only a general
paralleHsm of the broad classes of mollusks, but also repre-
sentative genera, and not a few species in common. The

58 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

proportion of cephalopods is essentially the same in each.
Although in the case of the Phoenix beds it seems somewhat
large, this is due rather to the neglect of the lower orders
than to their absence. It is not far from the truth to say
that the ratio of the cephalopods to the others is, in general,
one to five. The genera most commonly present in this
class are Pachydisciis, JBaculites, Hamites, and others of the
aberrant types. A few species of Desmoccras, Lytoceras^
and at least one species of Phylloccras are known to occur.
Phylloceras ramosum (Meek) is common to the three basins,
occurring at Mount Diablo, the " Forty-nine Mine," and in
the Nanaimo beds. Baciilites chicoensis is reported from the
Chico and Nanaimo groups along with Pachydiscus nciv-
berryaiius, and possibly P. sucta'ensis ; while the Nanaimo
and the Phoenix beds are further connected by Lytoceras
jukesi, and by representative species of Hamites and Bacu-
lites. Similarly the connection between the Chico and the
Phoenix beds is reinforced by the occurrence in each of
Schlanhachia chico'ensis{^x'A.^\C), and an Acanthoceras related
to A. rotomagense. Undoubtedly, however, the strongest
connections between the three basins are shown by the
large proportions of gasteropods and bivalves, very many of
which are specifically common to all of them. In addition
to Inoceramtis lahiatus, which is common to all the basins,
there is also /. crippsi, which is probably identical with
/. whitneyi. Two species of Trigonia, — T. tryoniana and
T. evansana, — are found alike in each of the three basins.
But the true relations can only be fully presented by com-
parative lists of species, such as the one published by Whit-
eaves, which cannot here be reproduced. Of the thirty or
more species there listed as common to the Nanaimo and
the Chico beds, more than half are found in the Phoenix
(and later) beds of the Oregon Basin. Others, common
only to the Phoenix and Nanaimo beds, and others, occur-
ring only in the Phoenix and Chico beds, still further
augment this number; and this is exactly what would be
expected in beds synchronously deposited in different
basins.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 59

It has been pointed out by Whiteaves and others that the
overhip of the Nanaimo strata in the Vancouver basin
accompanied a subsidence of the Cordilleran region which
resulted in the final connection of the Pacific and interior
waters. This has been conclusively established not only
by the presence of Inoceramiis labiatus, a form very abun-
dant in the upper portion of the Colorado group, occurring
also in the upper beds of the Queen Charlotte Islands, but
by others,

Whiteaves (1876-84, p. 188) has published a list of related
species, occurring in the upper beds of Vancouver and in the
Cretaceous of upper Missouri, which are intended to show
the commingling of faunas of this period. To these lists
may now be added other important forms from the later Cre-
taceous beds of Southern Oregon. No less than six species
of Scafhites, eight species of Schlocnbachia, two species of
PIacentice?'as, five species of Inoceramus, and many other
forms, have been found here that strongly recall the fauna
of the Colorado group. Nor is the resemblance one of
only general groups and genera. Many of the species
are either very closely related or are identical. Besides
Inoceramus labiatus, the list includes a species resembling
/. mytiloides Con., Prionocyclits branneri (very close to
P. zuoolgari (Mant.) Meek), Scaphites gillisi (still more
closely related to S. warreni M. & H.), and S. klamath-
ensis, which may be an equivalent of S. larvceformis
M. & H. from the lower portion of the Colorado. Other
members of the genus Schlocnbachia resemble Prionocychis
ivyomingensis. These species have been given other spe-
cific names; yet the very close affinities with those of the
Colorado group can hardly be doubted.

The close resemblances in the faunas of the more north-
ern Pacific border basins and those of eastern Asia are
shown in the following parallel lists from the Upper Creta-
ceous of the Oregon Basin and that from the Island of
Ezo (Jokoyama, 1889) : —

6o CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

Island of Ezo. Oregon Basin.

Desmoceras gaudama (pars), rel. Desmoceras hoffmanni Gabb
Desinoceras siigatiiui = Desmoceras sugatmn Forbes

Lyioccras sacya (pars) = Lytoceras sacya Forres

Lyioceras sacya (pars) cf. Lytoceras jukesi Sharpe

PachydiscHS arrialoorensis cf. Pachydiscus henleyensis, sp. nov.

Phylloceras villcdce, near rel. Phylloceras ramosuvi Meek

Inoceranius naiiinaniii rel. Iiwceraniiis klatnathcnsis, sp. nov.

Inocerainics sp., rel. Liioccrainiis ivhitneyi Gabb
Ciicullcea sachalinense {!), cf. CuciUUca truncata Gabb

Nucula picttiraia, cf. Nucula truncata Gabb

The Turonian aspect of at least the upper portion of the
Chico is very clear, as has already been pointed out by
different writers. It is further emphasized by some of the
above forms, which are known for the first time from the
Pacific border province in the Phrenix beds of Southern
Oregon. And to these may be added the great develop-
ment of the gasteropod and bivalve classes and many
aberrant forms of Helicoceras and Hamitcs, among which
is to be noticed an Jlclicoceras related to //. retisianwm
d'Orb., while the Turonian species, Inoceranuis lahiatus^
and many others ally these beds to the Turonian of Euro-
pean Cretaceous. But there are also contained in them
many forms that belong to a higher, as well as a lower,
horizon. BaciiUtes chico'cnsis and B . fairbanksi are both
closely akin to B. vagina Forbes, which is thought to be a
Senonian species. Numerous forms of Pachydiscus are
found in the Chico and its equivalents which would be
expected in Senonian equivalents; while the large develop-
ment of gasteropods and lamellibranchs shows a late period
of the Cretaceous. On the other hand, there are not a few
undoubted Cenomanian forms in the Lower Chico beds
which incline one to refer them to a lower position than the
Turonian. Among such forms are certain species of
Acanthoceras and some of the forms of Schlocnhachia.

In this connection also it ought to be said that the closest
relationship seems to exist between some of the forms of the
Lower Chico and some from the Ootatoor beds of Southern
India. Inoccrainus labiatiis is associated with Acanthoceras

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 6\

navicular e Mant., both in the Phcenix beds and in the
Ootatoor; but the Ootatoor beds have been correlated
with the Cenomanian, and both these forms are hkewise
found in rocks of that period in Europe. On the whole,
however, the strongest affinities are undoubtedly with the
Turonian; and if one remembers the great stratigraphical
range of some of the species of the Sacramento Valley, it
does not seem remarkable that Cenomanian or even Gault
types are found occasionally in the Chico.

Mention might be made here of the Upper Cretaceous
beds occurring on the west coast of Chile. Whether these
beds are to be correlated more closely with the Upper or
Lower Chico has not been very satisfactorily ascertained,
but a few of the species found there indicate a rather low
horizon. Phylloceras ramosiim occurs in the lower part of
the Chico in all of the more northern localities ; Desmocei'as
(Piizosia) darwini has a close ally in D. ashlandicutn of the
Phoenix beds; Lytoceras varuna is found in the Ootatoor
beds of India; and the Hamites, resembhng //. cylindraccus
de France, is also in accord with the lower horizon.

The exact position of Lytoceras kayei in the Californian
beds has unfortunately not been learned. It is only known
to come from the Chico of Mount Diablo. It appears,
therefore, that along the Pacific Coast of America from
British Columbia southward to Chile the overlap of the
later Cretaceous, including the Lower Chico and its equiv-
alents, is satisfactorily seen in most, if not all, of the widely
separated locahties of southern Vancouver, Rogue River
and Sacramento valleys, Southern California, Todos
Santos Bay, and Quiriquina Island, on the coast of Chile.
It seems hardly probable that a movement of so great
north and south range should be unaccompanied by parallel
disturbances in regions lying so nearly contiguous as that
of the interior basin ; and there appears to be both faunal
and stratigraphical evidence that contemporaneous move-
ments occurred in the two regions on opposite sides of the
Cordilleras.

CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

M
0
D

Danian
Senonian

c
0!

■5
0

C
o3

■5
03

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V

03
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Southern
India.

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South America

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Mexico.

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Island

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"No. 2" 0
(in part) cj

Southern
California.

Silverado

and
San Diego

San Luis
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British
Columbia.

Nanaimo and
"Div. Ar Q. C. I.

I/)

c
0
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"Div. C"
( in part )

Oregon
Basin.

Phoenix and
Henley beds

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Valley.

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Geol.— Vol.. II.] ANDERSON— CRETACEOUS DEPOSITS. 63

3. Equivalents of the Horsetown.

There are fewer known deposits of the Horsetown epoch
upon the borders of the Pacific, and they have thus far been
less studied than either the lower or upper horizons; yet
its equivalents are recognized in each of the Pacific border
basins, although in the Oregon Basin the typical cephalopod
fauna of the Upper Horsetown has not been shown to exist.
The close relationship, however, of the Horsetown and at
least a portion of the Queen Charlotte Islands section is
very much more clearly seen. Several species of the Upper
Horsetown fauna occur in a portion of "Division C " of
this section, and leave us accordingly but little room to
doubt their equivalence.

Among the connecting elements may be noticed the gen-
eral abundance of cephalopods, and especially those of the
genera Lytoceras and Desuioceras. Both these deposits have
many of the species and general cephalopod fauna of the
Ootatoor, as has been more especially emphasized by
Kossmat (1895), though previously recognized by others.
Among the forms common to the three regions, California,
British Columbia, and India, are Lytoceras ttmotheanuvi,
L. sacya, Desmoceras betidanti, D. planulattim, Sckhrn-
bachia injiata, and others apparently identical. As in the
Chico, so here additional species are found still more
closely connecting either two of these basins. Lytoceras
batesi, Desmoceras breweri, Nautilus sticiaensis, Ancyloceras
reniondi, species of Belemnites, and many other molluscan
forms are common to both the Sacramento and the Queen
Charlotte Islands sections. Schloenbachia propivgua is re-
ported from the Queen Charlotte Islands and occurs in the
Ootatoor beds. Forms connecting the Ootatoor and the
Horsetown are still more numerous. Among them are
probably the following: Phylloceras velledce (?=/'. ono'cnse
Stanton), Stoliczkaia di'spar, Lytoceras cala, Holcodiscns,
aff. H. theobaldiamis StoL, Desmoceras voyt, aff. D. hiti-
dorsatiis, and perhaps others.

Kossmat correlates the Ootatoor horizon and its equiva-
lents on the West Coast of America with the Cenomanian,

64 CALIFORNIA ACADEMY OF SCIE.VCES. [Proc. 3D Ser.

and there can be no doubt that many of the species do favor
that determination. At the same time, however, it must be
admitted that many of them are also more closely allied to
forms of the Gault.

It has been stated by R. T. Hill (1893), that in the Cre-
taceous deposits on the eastern border of the Cordilleras
a distinct unconformity exists between the strata of the
Comanche series and those of the Upper Cretaceous.
Rocks of the Dakota epoch are absent from large areas,
indeed, from the whole region extending from eastern
Texas to Wyoming and westward; while, at the same time,
there is evidence of a land-mass covering this belt from
which have been derived the littoral conglomerates of the
Dakota lying to the eastward. Furthermore, there is a
marked difference, both lithological and faunal, between
the deposits of the Comanche and those of the Colorado
and later groups, which extend far beyond the boundaries
of the Lower Cretaceous, reaching northward beyond the
region of the Upper Missouri. The rocks of the Comanche
series, consisting largely of marls and limestones, indicating
deep water conditions, are followed by clays and shales
and coarser detrital material, such as could only have been
deposited in shallow water.

The faunal differences are very great, although they
cannot be more than referred to here; yet it is worth while
recalling the comparisons that have been made between
these faunas and their contemporaries upon the Pacific
border. Stanton has especially emphasized the contrast
which is apparent betw^een the faunas of the Comanche
and the Shasta groups. It is not certain to what extent his
epitomized diagnosis is applicable for this purpose, since
he has included in the Shasta formation the whole of the
Horsetown, which evidently has, in large part, no marine
representatives upon the eastern border of the Cordilleran
continent. The Dakota group, which is the equivalent to
at least a portion of the Horsetown, is either absent or is a
non-marine, plant-bearing series, but which, moreover, in
any case is omitted from any part of the comparison.

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 65

Accordingly, almost the whole class of cephalopods listed
in his scheme have neither complementary elements nor
even contemporaries in the Comanche series. The con-
trast is therefore evidently less than it would appear to
be; but in so far as it is strictly applicable, it is quite
complete.

On the other hand, as has been already shown, when
the fauna of the Colorado group is compared to that of the
Chico, particularly as represented in the basin of Southern
Oregon, a strong resemblance is apparent, and there is
promise of a still closer relationship being recognized when
the fauna has become better known. In the paper by Hill
already referred to, the Dakota beds are given a position
equivalent to the Cenomanian, and the facts made use of in
the present paper are entirely in accord with that correla-
tion. It appears, therefore, that the hiatus which has been
here described as existing between the Knoxville (Pas-
kenta) and the Chico beds over so large a part of the
Coast Range region of the West, has its parallel and con-
temporary phenomenon in the deposits of the interior; and
the subsidence that followed the lateral extension of land
conditions on both sides of the Cordilleran continent, was,
therefore, epeirogenic; that is, it was synchronous on both
borders of that continent.

4. Equivalents of the Knoxville.

The earlier Cretaceous deposits of the Pacific border and
of Texas are more or less indirectly correlated, since there
is little or no faunal resemblance between them, and they
are too remote from each other to warrant a lithological
comparison. Still, it is not amiss to recall the facts that
the most calcareous portions of the California Cretaceous
are those of the true Knoxville (or Paskenta) strata, which
are often not unlike the Hmestones of the Comanche. It
is these horizons between which Mr. Stanton (1897, p. 608)
has pointed out such striking faunal contrasts, but of which
he says: "The two faunas are complements of each

66 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

Other, and both must be taken together to make up a really-
representative Lower Cretaceous fauna." Of their syn-
chrony he apparently has no doubt.

In his summary of the deposits of San Luis Potosi,
Mexico (Stanton, 1895, p. 26), he recognizes therein
equivalents not only of the Knoxville, but apparently also
of the Upper Cretaceous, possibly of the Horsetown ;
while below these is the lower division of group No. 2,
which he refers to the Jurassic. It shows a general resem-
blance to the fauna of the Mariposa beds in the large num-
ber of species of Perisphinctes, and in the presence of
Olcostephanus, Belemnttes, and Aucella.

The equivalents of the lowest portion of the Sacramento
section have not yet been clearly recognized. As to
whether the group which has been termed the Sub-Knox-
ville should really be classed with the Cretaceous or with
the Jurassic, there has been a difference of opinion. C. A.
White was convinced that but a single species of Aucella
was known from the Knoxville and from the Mariposa
beds; and the separation of these groups was not deter-
mined by a distinction of the species of this doubtful genus.
J. P. Smith (1895, p. 381) has expressed views strongly
favoring the Jurassic determination not only of the Sub-
Knoxville fauna with Aucella fiochi, but he also points
out the very close relationship between certain members of
the Knoxville fauna and the Volga stage of Russia. Quite
similarly, the lowest beds of the Queen Charlotte Islands
section, a portion of "Division C" of J. F. Whiteaves
(1876-84), has been compared to the same horizon of Russia.
The Knoxville horizon, as here restricted, has not been
shown to occur either upon the Queen Charlotte Islands
or upon the mainland of British Columbia. The relation-
ship between these beds and the Russian deposits appears
most strongly in some of the ammonites, which have not
been found-in any of the Californian beds. If this obser-
vation proves to be trustworthy, then the Sub-Knoxville of
the Sacramento basin is perhaps the equivalent of the low-
est member of the Queen Charlotte Islands group, or of

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 6'J

"Division C," and both may be compared to the Volga
stage and similar deposits.

Among the authors whose opinions are of more than
ordinary weight upon this topic may be mentioned the name
of Emil Haug (1898, p. 226). While conceding the Neoco-
mian equivalency of the upper portion of the Knoxville
(evidently the Paskenta), he plainly states that the lower por-
tion of the "Knoxville beds" undoubtedly corresponds to
the upper Portlandian of the Mediterranean region, which
he correlates with the upper Volgian, the Tithonian and
the Purbeck beds, and to the same horizon he refers the
Jurassic portion of the series found at Catorce in the State
of San Luis Potosi, Mexico. This seems to be on the
whole the most satisfactory correlation of these beds yet
suggested.

5. CORDILLERAN OSCILLATIONS.

The subsidence recognized independently for the regions
of Texas and California was synchronous throughout the
Cordilleras. It culminated with the close of the Comanche-
Knoxville epoch, attaining, probably, as great a depression
in these regions during the Cretaceous period as has since
been reached. The sea extended over western Texas and
eastern Mexico nearly, if not quite, to meet the waters of
the Pacific, which covered western Mexico.

Following this period of depression was an epeirogenic
uplift of the Cordilleran continent, which threw the
shore-lines seaward upon both of its borders and thus cor-
respondingly expanded the terrestrial areas, and excluded
accordingly from the territory thus added to the continental
margins the contemporaneous deposits of the Dakota and
the Horsetown groups.

Following the upHft of the Cordilleras were the disturb-
ances that resulted in the contemporaneous overlaps of the
Chico and of the Colorado, and the continued subsidence
of the remon until marine communications were estabHshed
between the interior basin and the Pacific Ocean, which
enabled species to pass from one to the other unobstructed.

68 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

The return of the sea upon the continental borders resulted
in the deposition of Cenomanian equivalents upon the older
Cretaceous deposits unconformably, as is seen on the one
hand, between the Knoxville and the Chico, and on the
other, between the Comanche and the Colorado.

How widely spread this unconformable relation may
appear to be remains to be discovered, but judging from
the almost continuous series of the Cretaceous deposits in
favorable localities, it can hardly be expected that uncon-
formities will always be found where Comanche and Colo-
rado rocks are present. The double character of the
Chico group reminds one alike of the Trichinopoly and
Arrialoor of the Indian Cretaceous, of the later subdivi-
sions of the Rock}^ Mountain section, and of the Turonian
and Senonian overlap upon the European continent. It
therefore appears that disturbances of a similar character
occurred in very remote regions during the closing epochs
of the Cretaceous period.

VIII. Summary and Conxlusions.

The foregoing discussion of the Cretaceous deposits of
the Pacific border is designed to contain a statement of our
present knowledge of the subject, and particularly of the
Cretaceous deposits of California and Oregon. An at-
tempt has been made to revive the earlier views regarding
the complexity of the series, which have been to a con-
siderable extent suppressed. The view more recently
maintained, that the series is one of comparative simplicity,
even in its most complete developments, has proved to be
misleading when applied to districts outside of a rather
restricted basin. The series at its best cannot be called
simple, its continuity having been frequently disturbed
even when deposition was most uniform in the basin of
the Great Valley. While the disturbances have not always
been sufficiently great to destroy all existing marine species,
and thus obliterate faunal connections between deposits of
succeeding epochs, yet it is evident that only the most

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 69

persistent forms have survived from one epoch to the next.
The faunal evidence of such disturbances is reinforced by
the abundance of conglomerates which are interstratified
with sandy and shaly beds, especially in the upper portion
of the series. Coincident with the evidence of these facts
is that of the territorial distribution of different members
of the series in California and Oregon.

The Cretaceous series of the Sacramento basin and of
the whole Pacific border (excluding the Sub-Knoxville,
which is probably of pre-Cretaceous age), is divisible into
the following well defined members: (i) The Knoxville
horizon, including several thousand feet of strata extending
upward to the upper limit of the present known species of
Aucella, embracing what has been shown to be essentially
a boreal fauna; (2) the Horsetown horizon, beginning
with the close of the Knoxville and the substitution of a
typical subtropical fauna for one of boreal character, and
continuing to the horizon representing the great Chico
overlap; (3) the Chico, or uppermost member of the
series, as represented in the Phoenix beds and the beds of
Wallala, Silverado Canon, Point Loma, and Todos Santos
Bay, Lower California.

The fauna of the Chico is characterized in its later por-
tions by a large development of gasteropods and lamelli-
branchs. It is divisible into two horizons, at least in the
Sacramento basin, and perhaps elsewhere. The move-
ments that have affected the region are to be inferred from
the relations thus recognized. Their general order, par-
ticularly in the basin of the Great Valley, has been down-
ward from the first, but not continuously so. With the
close of the Knoxville epoch, an interval of epeirogenic
uplift prevailed, which withdrew a large amount of terri-
tory from oceanic submergence, but which in favored
places may have caused only a cessation of deposition, as
in the Great Valley basin. The extent of this disturbance,
and the duration of the interval, may be inferred from the
great faunal change which was introduced with the Horse-
town epoch. This was the most important disturbance of

(6) December 3, 1902.

70 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 30 Ser.

the period, and was accompanied by extensive intrusions
of peridotite in the Coast Range region of California and
Oregon.

Succeeding the post-Knoxville elevation, the next great
movement was that inaugurating the Dakota and later
Horsetown disturbances, which later were followed by the
great overlaps, extending along the Pacific border of both
North and South America, from the coast of Chile to
British Columbia, and in the interior basin, carrying the
Upper Cretaceous far northward along the flanks of the
Cordilleras. It was therefore of an epeirogenic nature,
extending in longitude as well as latitude over great inland
areas.

The close of the Chico epoch is not yet sufficiently well
understood for any final statements; but the faunal differ-
ence between this epoch and that of the Martinez, as
restricted by J. C. Merriam, shows a hiatus, probably be-
tween the Chico and the Eocene deposits of the Pacific
border.

The different members of the Cretaceous series of Cali-
fornia find their counterparts in other portions of the Pacific
border, in British Columbia, Mexico and Chile, and are to
be closely correlated with the recognized members of the
interior basin deposits, with those of Asia and of Europe.
This is shown not only by the parallelism of their develop-
ments, but also by their faunal resemblances, amounting
often to close specific affinities, and even specific identity.

The crustal movements that have affected the Pacific
border of America have been much more general than has
been commonly believed. Simultaneous disturbances of
the same tendency may be traced in many of the great
Cretaceous series of the world.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 7 1

Part II.

Description of Species.

In the following descriptions of fossil species, it has been
the endeavor, whenever possible, to recognize from previ-
ously published figures and descriptions the forms that have
been found by others and listed as authentic species.
There are among the collections of the University of Cali-
fornia many type-specimens from which Gabb's original
descriptions were made, and considerable other material
which was labeled by Mr. Gabb and turned over by the
State Survey to the State University. Such material has
proved to be of great service in the identification of species
described in the publications of the State Geological Sur-
vey. Much kindly interest has been shown, and great
assistance given in the preparation of this paper, by those
chiefly interested in extending our knowledge of West
Coast geology, and especially of Pacific Coast Cretaceous
deposits.

It is not improbable that when the Cretaceous fauna of
California becomes better known many of the species that
have been described as new will prove to be either identical
with, or very closely allied to, Atlantic or to other Pacific
forms. It is with this feeling that man}^ of the names are
proposed in the present descriptions; but an identification
of this kind will not be retarded by the attachment of mere
names, while the published descriptions of these forms will,
it is hoped, stimulate closer comparison.

It is evident to any one familiar with the different types
of the genera Lytoceras and Desmoceras that too much lax-
ness has been allowed in the determination of species.
Forms that have barely more than a general resemblance
have been included under a common name. Note, for
example, Desmoce?'as jtigalis, Desmoceras hoj'nianni, Lytoc-
eras batesi, and many others.

72 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

BRACHIOPODA

1. Rhynchonella densleonis, sp. no v.

Plate VII, Figs. 157 and 158.

Shell of medium size, attaining a diameter of 11-12 mm.; trigonal; gib-
bous; when full grown, the greatest convexity being near the middle; poste-
rior lateral margins straight, sloping from the beak at an angle of about
90 degrees; anterior margin somewhat broadly rounded; dorsal valve more
convex than the ventral, nearly globose; ventral valve flattened, though
bearing a deep sinus; anterior half of each valve bearing strong, rounded or
angular plications which disappear on the posterior portion of the shell; sur-
face of both valves bearing fine striations most plainly seen on the posterior
half of the shell. The sinus of the ventral valve bears three or four plica-
tions, while the corresponding prominence on the dorsal valve bears four or
more; beak not very prominent and only slightly curved; deltidium small;
width of shell greater than length.

This species seems to be very closely related to Rhyn-
chonella gnathofhora Meek.^ Whiteaves states that R.
matidensis Whiteaves^ also resembles Meek's species, and
it is therefore not unlikely that the two Cretaceous species
are identical.

Occurrence. — This species is not uncommon at Horse-
town, Shasta County, California, in the uppermost beds of
this division. In this respect it may also agree with
R. matidensts.

2. Rhynchonella whiteana, sp. nov.

Plate VII, Figs. 160 and 161.

Associated with the former species is another somewhat related form, with
a finer and more subdued sculpture. The ventral sinus bears about nine or
ten plications of uniform size and none of the strong folds of the other. The
shell is rather circular in outline. The dorsal valve is crossed by two diverg-
ing ridges meeting on the anterior margin the borders of the ventral sinus.

» Pal. Cat., Vol. I, p. 39, PI. VIII.
* Mes. Foss., Vol. I, p. 252.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 73

LAMELLIBRANCHIATA

3. Inoceramus adunca, sp. nov.

Plate IX, Figs. 188 and 189.

Shell equivalve or nearly so, narrowly oval; margin elliptical; anterior side
short, rounded, sloping rapidly from the beaks; base forming a broad curve;
posterior side longer than high, meeting the basal margin in a rounded point;
beaks high, very prominent and full, forming a strongly curved hook; surface
having moderately strong concentric ridges, not regularly disposed.

Length of shell 5.8 cm.; height 3.15 cm.; thickness of each valve 2.25 cm.

This shell recalls by its strongly curved beaks some of
the species of the Colorado group of the Upper Missouri
section.

Occurrence. — A single specimen of this shell was found
at the Forty-nine Mine, near Phoenix, Oregon, associated
with species of Schlcenhachia, Scaphttes, Lytoceras, and
Desmoceras. It apparently belongs to the horizon of the
Lower Chico.

4. Inoceramus klamathensis, sp. nov.
Plate IX, Figs. 185 and 186.

Shell small, not attaining a size much above that shown in the figures, in-
equivalve, the left valve being much more strongly arched, the right being
somewhat flattened, or compressed; left valve showing a tendency to form
an umbonal angle and depression at mature age; hinge line short, and form-
ing an angle of 60 degrees with the anterior margin.

In the largest specimen found the length of the shell from the point of the
long, narrow beak to the extreme border is about 40 nim., width 25 mm.;
curvature of the left valve about 15 mm.

Occurrence. — This species was found in the Lower Chico
beds of Willow Creek, Siskiyou County, California, and
at the Forty-nine Mine in Southern Oregon.

5. Pholadomya anaana, sp. nov.

Plate VII, Fig. 151.

Shell gibbous, oval, rounded on the anterior and lower margins, narrowing
rapidly behind; beaks subcentral, but a little in advance of the middle, high

74 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 30 Ser.

and incurved; surface marked with fine, regular, concentric lines; radiating
ridges, usually six in number, crossing the posterior surface, the last and
heaviest one followed by a groove extending from the beak to the margin;
hinge not distinct.

Length of shell, 2.5 cm. or more; height, 2 cm.; thickness, 1.6 cm.

Occurrence. — The species is known from five or six
specimens obtained by Dr. Fairbanks from the Santiago
and the Silverado canyons of the Santa Ana range in
Orange County, CaHfornia. It was associated with Pcc-
ttmctilus -pacijictis, Schlanbachia gahhi, and other species
known only in the Lower Chico. The same, or a very
similar species, is reported by Dr. Smith from the Lower
Chico of the San Fernando Mountains, Los Angeles
County, California.

6. Pectunculus pacificus, sp. nov.
Plate VII, Fig. 159.

cf. Pectunculus subplanatus Stol., Pal. Ind., Vol. Ill, p. 347, Pis. XVII
and XLIX.
Shell subcircular, compressed; beaks central, low, sometimes a little prom-
inent; surface nearly smooth, yet marked with fine radiating strite and a few
faint lines of growth; thickness of shell two-thirds the vertical diameter;
hinge-margin angularly truncated in some specimens, both anteriorly and
posteriorly; diameter generally 1.5 to 3 cm.

Occurrence. — The type of this species was obtained by
H. W. Fairbanks from the Santiago Canyon of Orange
County, California, where it is associated with Schlccnbachia
gabbi, Baculites, fairbanksi, and other species that are
known only from the lower portion of the Chico. It occurs
also in the lower Chico beds of Southern Oregon, at the
Forty-nine Mine, and the Smith ranch.

The type of this species is the property of Dr. H. W.
Fairbanks, Berkeley, California.

7. Mactra gabbiana, sp. nov.
Plate VII, Fig. 156.

Shell moderate in size, somewhat resembling M. ashburneri Gabb, but
generally with a heavier shell, and more strongly grooved concentrically;
umbonal angle strongly marked, especially near the base; anterior surface
flattened but not excavated.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 75

Gabb appears to have seen this species in the Chico beds
of California, but did not distinguish it from M. ashburneri
Gabb.

Occurrence. — This species occurs in the Lower Chico
beds of Henley and Willow Creek, in Siskiyou County,
and in the Santa Ana and Temescal mountains of Los
Angeles and Riverside counties, in California.

GASTEROPODA

8. Haliotis lomaensis, sp. nov.

Pl.\te IX, Fig. 183.

Shell small, length 1.3 cm., oval, the two lateral margins nearly equally
curved; convex, the back angled at the row of perforations; spire low, indis-
tinct, not terminal; lips continuous around the spire end, expanded along
both sides, forming a thin margin; muscle-impression central, oval, slightly
roughened; perforations four, preceded by a slight marginal notch, and pro-
duced ridge behind; surface marked by concentric lines extending around
the entire body-whorl near the margin; radial lines also seen; convexity of
shell about one-fourth the length ; width five-sixths the length.

This shell appears to resemble in many respects Tryon's
group of H. iris.

Occurrence, — The type of this interesting species, which
is in the collections of the State Mining Bureau, San Fran-
cisco, was obtained by H. W. Fairbanks from the Lower
Chico of San Diego County, California. A single speci-
men was found in the beds at Point Loma, associated with
Pecten californicus, Actceonina pic^oides, and Upper Chico
forms; but below the beds contain Coralliochama orcutti,
according to the statements of Dr. Fairbanks. It is doubt-
less the oldest Haliotis known, being somewhat lower in
position than the //. antiqua Bink. of the Maestricht beds.

9. Erato veraghoorensis (?) Stol.
Plate IX, Figs. iSi and 182.

Erato (?) veraghoorensis Stol., Paleont. Ind., Vol. II, p. 59, PI. IV, fig.
14, etc.
Shell ovate, more inflated posteriorly; spire low though distinct, about
one-eighth of the entire length of the shell; outer lips thickened and reflexed,

76 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D vSer.

broadly rounded, denticulate with fine ridges on the inner margin; aperture
narrow, somewhat S-shaped, a little wider at anterior end; shell notched both
before and behind; inner lip rounded, not known to be toothed; surface
smooth and polished. The outer lip is slightly expanded posteriorly in an
ear-like elevation that rises to a level with the low spire. The anterior end
of the inner lip is bent a little downward just before reaching the forward
notch. Both notches are somewhat shallow, the posterior one showing an
upward curve or groove between the spire and the ear-like expansion of the
outer lip.

Occurrence. — One good specimen of this shell was found

at the Smith ranch, Oregon.

10. Gyrodes siskiyouensis, sp. nov.
Plate VIII, Figs. 167 and 168.

Shell moderate in size, subglobose, though a little compressed, spire low;
upper surface a little flattened near the suture, forming a narrow ledge and
angle; the whole surface plainly marked by revolving lines, most developed
near the angle above; umbilicus open and slightly angled; no lines of growth
visible, except on perfectly preserved shells.

Occurrence. — This shell is common on the north slope of
the Siskiyou Mountains, in the Chico beds. It occurs
with Dcsmoceras ashlandicum, and CuciiUcea truncata, and
many other gasteropods and bivalves that belong to the
Chico.

II. Anchura condoniana, sp. nov.

Pl.\te \III, Fig. 179.

Shell large, robust, with high spire; whorls about eight in number, moder-
ately rounded; surface of spire ornamented by twenty or more longitudinal
ridges; body-whorl entirely covered by longitudinal and revolving ridges
equally developed; lip long and falcate, extending laterally, but bearing a
spur-like process near the spire; lip strongly angled along the back, with
angle extending upon the body-whorl; lip also bearing an angle on its outer
margin.

Occurrence. — This species was found in the Lower Chico
beds of the Forty-nine Mine, near Phoenix, Oregon, asso-
ciated with many species of Schlcenbackia and Scaf kites.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. *J*J

CEPHALOPODA

NAUTILOIDEA
12. Nautilus gabbi, sp. no v.

Nautilus texanus (?) (Shum.) Gabb, Pal. Cal., Vol. I, p. 59, PI. IX.

There is in N. gabbi about the same number of septa that Stoliczka states
commonly occurs with A^. kayeaniis; the umbilicus is similarly small, though
not closed, the position of the siphuncle is subcentral, a little nearer the base
of the septa, and the ornamentation of the shell is the same in so far as the
flexuous radial markings are concerned. There is the same backward curve
upon the ventral surface. Small specimens of the Shasta species show in
addition to this some fine revolving striae that give a beautiful cross-hatched
sculpture that is not seen in any of the older specimens.

This species of A^autilus,\Y\nch. Gabb doubtfully referred
to the Texan species, has recently been collected upon Cot-
tonwood Creek, by Dr. J. P. Smith. It agrees in all respects
with Gabb's figures, and it seems probable that it was from
one of the specimens obtained from Shasta County that the
figures were made. Gabb reports the species also from
Mount Diablo, but the identity of the two species ought to
be accepted with hesitation. It resembles in some respects
JV. campbellt Meek from Comox, Vancouver Island, and
might be mistaken for this species.

Nautilus gabbi \% closely related to N. kayeaniis Stol. from
the Ootatoor beds of Southern India. Stoliczka considers
his species a representative of a group of associated forms,
one of which he identifies with N. fscudo-clegans d'Orbigny.

Occurrence. — Nautilus gabbi is found in the Upper
Horsetown beds of Shasta Count}', California, though its
range has not yet been ascertained.

Two specimens of a Nautilus labeled " Claytons, Contra
Costa County" are among the Pioche collection at the
University of California. They apparently belong to a
distinct species, in which the umbilicus is entirely covered
by a thick callous, and which has a characteristic ornamen-
tation of surface. The dark coloration is preserved upon

78 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

the portion covered by the body-whorl in one of the speci-
mens, and the outermost layer is marked by minute granu-
lations that have a systematic arrangement in rows parallel
to the median plane.

13. Nautilus charlottensis Whitcaves.

Nautiltts sttciaensisyNH\TK\\'Ti.s, Mes. Foss., Vol. I, 1876-84, p. 197, PI. XXI.
Nautilus charlottensis Whitcaves, Mes. Foss., Vol. I, p. 269.

A fine example of this species was found at Horsetown,
Shasta County, California; it is in the museum of Stanford
University. Whiteaves reports it from the Upper Creta-
ceous of the Queen Charlotte Islands. In the Horsetown
examples the siphonal tube is perhaps a little lower in its
position than in the northern specimens. It appears to be
very similar to JV. pseudo-clegans d'Orbigny,' although the
position of the siphonal tube is a little higher than in
d'Orbigny's figure. There is a relationship between N.
gabhi and ^V. charlottensis, similar Indian species mentioned
in the preceding description.

14. Nautilus sp.

Among the collections obtained by Dr. Bowers from the
Santa Ana Mountains are two imperfect specimens of
NaiitiliLS that appear to be related to N. gabhi and N. char-
lottensis, though not identical with either. It forms, perhaps,
a third member of this group belonging to the Pacific border
province.

AMMONOIDEA.
15. Placenticeras californicum, sp. nov.

Plate VIII, Figs. 173-177.

The shell is discoidal, compressed, narrowing regularly from the umbilical
region outward; inclined to be rough or with coarse ribs; costee flexuous,
extending to the umbilicus, and terminating outward in tubercles upon the

1 Pal. Franc. Terr. Cret., Vol. I, Pis. IX and XIX.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 79

peripheral angle; tubercles elongated and narrow, standing in single rows on
either side of the ventral surface, and opposite one another. The ribs are
low and rounded, and about equal in width to the intervening furrows. On
old shells they reach the number of about forty on an entire whorl, while on
younger shells the number is generally less. The ribs incline strongly for-
ward on leaving the umbilicus, but about the middle of the shell describe a
sharp curve backward, followed by a more gentle forward curve on approach-
ing the marginal tubercles. Upon the periphery the space between the rows
of tubercles is flattened and band-like, being equal in width to one-third the
thickness of the shell. The early stages of this shell have been described by
Dr. J. P. Smith, ^ and its relations to the next species stated.

Hitherto the genus Placcnticeras has been but little known
in the Cretaceous of the Pacific border. Two allied species
have recently been recognized in the Lower Chico beds in
widely separated districts in California and Oregon. In
the above named species the shell is of moderate size, the
largest specimen having the following dimensions: —

Diameter 120 mm.

Height of last coil 58 mm.

Width of last coil 30 . 5 mm.

Width of umbilicus 23 mm.

Involution 13 mm.

Occurrence. — This shell is known from the Lower Chico
of Phoenix, Henley, Arroyo del Valle, and the San Fernando
Mountains.

The type is in the collections of the University of
California.

16. Placcnticeras pacificum Smith.

Plate VIII, Figs. 162-164 and 171-172; Plate IX, Fig. 180.

Placeiiticer as pacific iivi Smith, Proc. Cal. Acad. Sci., 3d Ser., Geol., Vol. I,
pp. 207-210, Pis. XXV-XXVIII.

Shell discoidal, involute, compressed, and moderately smooth; size of
largest shell about 16.5 cm. in greatest diameter. The species is related to
the preceding and superficially differs from it chiefly in being smoother and
more graceful in its ornamentation. As shown in the figures and description
(1. c), in its younger stages it is characterized by its smooth form, without
ribs or tubercles. The development of the two species is entirely different.

1 Proc. Cal. Acad. Sci., 3d Set. Geol., Vol. I, p. 181.

8o CALIFORNIA ACADEMY OF SCIENCES. [Proc. .^d Ser.

Occurrence. — The species occurs with the preceding at
Phoenix, Henley, and Arroyo del Valle, and Dr. Smith
states that he has found it in the Lower Chico beds of the
Silverado Canyon, Orange County, California.

17. Phylloceras shastalense, sp. nov.

Plate IV, Figs. 112-115.

Shell small, inflated, not globose, rapidly increasing in width; section of
body-whorl nearly circular, but in younger stages elliptical; umbilicus closed,
or not showing any of the earlier whorls, except in minute specimens; surface
crossed by transverse ribs that are tolerably coarse compared with those of
other species lower in the series. The ribs begin at the umbilical depression
and run transversely over the ventral surface, making only slight curves.
The diameter of the largest specimen found is 3 cm., from which most of the
body-chamber is missing. The suture is clearly that of a Phylloceras. It
does not appear to be closely related to either of the previously known forms
of this genus from the Pacific Coast. It is more nearly allied to Ammonites
rouyanus d'Orbigny'^ though less flattened ventrally than this species, as
represented in the figure.

Occurrence. — This species is quite common at Ilorsetown,
Shasta County, California, where four or five good speci-
rhens were recently collected.

The type is in the collection of the University of
California.

18. Schliiteria diabloensis, sp. nov.
Plate III, Figs. 105-106.

Among the ammonites labeled by Gabb ^^Am. jugalis''
is an undescribed species of Schliiteria for which the name
S . diabloensis is here proposed.

The greatest diameter of the largest specimen is 2.5 cm., with a thickness
near the umbilicus of 1.2 cm. The umbilicus is small, with sides that become
very abrupt at this diameter, though the younger portion of the shell shows
more gentle slopes. The sides are apparently smooth or marked with a few
faint transverse grooves, and are flattened and gently converge outward.
The fine lines of growth curve a little backward after crossing the umbilical
shoulder. The suture is that of a Desmoceras, though in shape and gen-
eral appearance the species might be considered a Phylloceras.

spal. Franc. Terr. Cret., Vol. I, PI. CX, figs. 3-5.

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 8l

Occurrence. — The specimen from which the figures have
been drawn is labeled " Mt. Diablo," and being in a collec-
tion with several others of the same species from Curry's
is probably also from that locality. Other species from this
locality, as stated elsewhere, show a low horizon of the
Chico.

The type is in the collection of the University of California.

19. Lytoceras rel. duvalianum d'Orh.

Plate VI, Figs. 140-143.

Ammonites duvalianus d'Orb., Pal. Franc. Terr., Vol. I, PI. L.

Among the close allies to European forms found in the
Cretaceous of the Pacific Coast, there are few that seem
more truly identical than this one. If d'Orbigny's figure
represents the suture of this species correctly, both lobes
and saddles are relatively narrower in the California types,
otherwise there is but little difference, unless it is in the
less equal division of the lobes. The form of the shell
and its surface markings are too nearly like d'Orbigny's
species to justify any other name being applied at present.
There are certainly greater ranges of variation recognized
in nearly all Cahfornian types than there appear to be
between the specimens from California and the European
form as figured by d'Orbigny.

In the young shell from the Shasta beds the constrictions are scarcely
noticeable but begin to appear upon the sides, without crossing the ventral
surface, at a diameter of 3 cm. They reach their clearest development at 4
or 5 cm., and then again diminish. At first they form upon the sides only
broad, undulatory ridges, between which the constrictions become more
sharply defined with growth, becoming deeper upon their posterior margin
and diminishing in depth forward. Between the constrictions, which are
about twenty in number, the surface is covered by fine transverse lines, yet
the shell has an almost polished appearance. The section of the whorl is
quadrate in the adult but is more rounded upon the ventral side in youth.
The walls of the umbilicus are abrupt, and the involution covers about one-
half of the width of the whorl.

Occurrence. — Two good specimens of this species, one
of which is the type, were found near the mouth of Hulen

82 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

Creek, and three were obtained at Horsetown, Shasta
County, California. L.ytoceras duvaliamun d'Orbigny is
found in the Neocomian of Europe.

The types of this species are among the collections of
the University of California.

20. Lytoceras (Tetragonites) jacksonense, sp. nov.

Plate V, Figs. 124-125.

Shell moderately compressed, rounded, smooth; size of type 6.33 cm. in
diameter; umbilicus rather narrow, walls steep, rounded on the shoulders;
involution covering the larger part of the preceding coil; section subcircular,
somewhat quadrate, slightly thicker near the umbilical shoulder, from whic^i
zone the sides slope gently toward the periphery. Faint grooves are to be
seen obliquely crossing the sides and inclining forward, and forming upon
the ventral surface a wide, backward curve, very much as is seen in the next
species, to which this one is somewhat related. Faint lines of growth are
barely perceptible upon the portions of test yet remaining, which are parallel
to the grooves. The suture consists of four or five very much divided sad-
dles, narrow, and unequally bifid, the outer branch of which is the smaller.
The lobes are relatively wider, with branches terminating in pointed denti-
cles. The division of the lobes is more equally bifid than that of the sad-
dles. Both lobes and saddles diminish uniformly in size from the e.xternal
side inward to the umbilicus. The small siphonal saddle is narrow and
denticulate.

Occurrence. — A single specimen of this shell was ob-
tained from the Forty-nine Mine, near Phoenix, Oregon.
The locality has been referred to the Lower Chico beds in
the body of this paper.

The type of the species is in the California Academy of
Sciences.

21. Lytoceras (Gaudryceras) sacya Forbes.

Ammonites sacya Forbes, Trans. Geol. Soc. Lond., Ser. II, Vol. VII,

1845-56, p. 113.
Ammonites sacya (Forbes) Stol., Pal. Ind., Vol. I, p. 154, PI. LXXV.
Ammo7iites whitfieyi 0\v.^, Pal. Cal., Vol. II, p. 134, PI. XXII, 1869.
Lytoceras sacya Whiteaves, Mes. Foss., Vol. I, 1876-84, Pt. I, p. 43, etc.
Lytoceras (Gaudryceras) sacya Whiteaves, Mes. Foss., Vol. I, 1876-84,

Pt. IV, p. 270.

In the upper portion of the Horse*town beds this species
is fairly abundant and generally takes the place of

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 83

Lytoceras baiesi, occurring lower in the series. Aiinjwnitcs
whitneyi has not yet been clearly recognized as a distinct
species, and to any one familiar with the fauna of this hori-
zon there can hardly be a doubt that Gabb's species and
Lytoceras sacya are the same. Gabb's figure is apparently
defective, showing too deep and too early constrictions on
the shell. On older specimens of Lytoceras sacya these
appear to be constant, but are lacking on shells below a
diameter of 6.33 centimeters.

Occurrence. — Lytoceras sacya occurs in the Upper Horse-
town beds of California, and the Lower Chico beds of
California and Oregon, and in beds equivalent to the
Upper Horsetown on Queen Charlotte Islands.

22. Lytoceras (Gaudryceras) kayei Forbes.

Ammonites kayei Forbes, Trans. Geol. Soc. Lond., Ser. II, Vol. VII,

1845-56, p. lOI.
Ammonites tiayei (?) (Forbes) Stol., Pal. Ind., Vol. I, p. 156, PI. LXXVII,

fig. I.
Lytoceras tiayei Forbes, Stein., Jahrb. f. Min., etc., Bell.-Bd. X, 1895-96,

p. 86.

Shell discoidal, thin, increasing very slowly in diameter; section of the
whorls transversely elliptical; umbilicus wide and shallow, coils small, orna-
mentation simple, surface crossed by oblique lines and a few moderately
deep grooves. Septation well represented by Steinman's figure (1. c, p. 87).

There are few more interesting discoveries here noted
than the identification of this characteristic Upper Creta-
ceous species from the Chico beds of California. The
shell in all of its details of ornamentation and sutures is
almost the exact facsimile of the species from the west
coast of Chile and from the Pondicherri District of Southern
India, as well as can be judged from the figures.

Occurrence. — A single well preserved specimen from
Mount Diablo is in the collections of the University of
California.

84 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

23. Lytoceras (Tetragonites) cala (?) (Forbes) StoUczka.

cf. Ammonites cala Forbes, Trans. Geol. Soc. Lond., Ser. II, Vol. VII,

1845-56, p. 204.
Ammonites cala (?) (Forbes) Stol., Pal. Ind., Vol. I, p. 153, PI. LXXV.

In the collections of Lorenzo G. Yates, temporarily^
deposited at Stanford University, are several specimens of
a Lytoceras of the genus Tetragonites, which appear to be
referable to L. cala, as described by Stoliczka. They
have been compared with both Forbes' and Stoliczka's
figures, but so far as can be ascertained by this means they
agree more nearly with the latter. They are from the
Arroyo del Valle, eight miles southeast of Livermore, Ala-
meda County, California.

In all respects they agree perfectly with Stoliczka's
description. The shell is evidently a close relative of
Forbes' species, which could be distinguished from it onl}^
by a comparison of types.

Shell discoidal, flattened on the sides, and of a diameter not exceeding
7.6 cm.; umbilicus wide and shallow, with abrupt walls; involution very little,
clasping little more than the flattened ventral surface; shell increasing slowly
in size with growth; section of whorls tetragonal; suture consists of three
lobes on each side, with auxiliary lobes much reduced, upon the umbilical
surface. The siphonal lobe is broad, divided by a denticulated tongue-
shaped siphonal saddle.

Occurrence. — There are in the Yates collection four or
five specimens of this shell, all of which have been obtained
from the Jordan ranch on the Arroyo del Valle, eight miles
southeast of Livermore, Alameda County, California. The
horizon is that of the Lower Chico. Stoliczka says L. cala
is from the Ootatoor beds of India.

24. Lytoceras bates! (Trask) Gahh.

Under the specific title of Ammonites hatesi Gabb included
three quite clearly marked species which he recognized as
only varieties. In all the larger collections of Cretaceous
fossils in California there are numerous specimens of
related forms bearing this name. The confusion is the

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 85

result of Gabb's failure to recognize the true differences
in these forms. The various representatives of the species,
as understood by Gabb, for the most part may be easily
separated into this and the two following types : Lytoceras
batesi Trask (s. s.), Proc. Cal. Acad. Sci., Vol. I (2d Ed.)
1855, p. 39; Pal. Cal., Vol. I, p. 67, pars., PI. XIII.

The most striking difference between this species and the
next one is in the rate at which they increase in diameter
with growth. In Trask's original type this increase was
relatively slow. According to his description, at a diameter
of 14 cm. the width of the aperture measured 3 cm. Gabb's
figure^ was probably drawn from Trask's type specimen.
According to Trask, the section of the whorl is about cir-
cular ("convolutions nearly round "). Both these charac-
teristics were overlooked by Gabb, who included with it two
species very different in both these respects.

Occurrence. — It is not easy to decide the exact range of
this species from the statements of Gabb. Evidently,
though, it is found well toward the bottom of the Horse-
town, and seems to have a wide stratigraphical range.

25. Lytoceras argonautarum, sp. nov.

Plate VII, Figs. 154-155.

Ammonites batesi (pars.) Gabb, Pal. Cal., Vols. I and II, 1863.

Shell discoidal, somewhat inflated, increasing rapidly in size; section of
whorls not quite circular, flattened slightly on sides and ventrum; umbilicus
deep, walls rapidly becoming steeper outwardly; involution slight, like that
of the preceding species; suture similar to that of Lytoceras batesi, but cor-
respondingly heavier and less regular; lateral lobes not equally bipartite,
small siphonal saddle lanceolate, with minute denticulations; surface orna-
mented with rounded, evenly spaced ridges, separated by wide, smooth, and
shallow grooves, and in this respect unlike L. batesi.

The type from which the figure was drawn was obtained
by Dr. J. P. Smith, one and one-half miles east of Ono,
Shasta County, California. Its greatest diameter is 17.1 cm.,

iPal. CaL, Vol. I, PL XIII.

(7) December 10, 1902.

86 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

while the corresponding width of the umbilicus is 5.7 cm.
The specimen is the inner coil of a much larger shell,
30 cm. in diameter. The aperture is not circular, but has
a width of 8.4 cm,, and a depth of 7 cm. In this specimen
the removal of one complete volution would reduce the
diameter to 3.3 cm. Another specimen of the same spe-
cies in the collections of the University of California, meas-
uring a little over 40 cm. in diameter, would, by the removal
of two complete volutions, be reduced to almost the same
dimensions, 3.3 cm. The aperture of this gigantic speci-
men measures 15 cm. in diameter. It does not contain the
whole of the body-chamber, which would have consider-
ably increased its diameter. This is evidently the species
represented by the specimen to which Gabb has alluded^
as the "largest known species of California." It is not
very difficult to recognize even the young shells of this
species when compared with typical specimens of L. hatesi
of the same diameter, or of the same number of coils. A
specimen of this shell in the collections of the University of
California measures sixteen inches in greatest diameter.

Occu7'rence. — This species is found in the upper portion
of the Horsetown, though its downward range is not known.
Dr. Smith states that he has found what is probably the
young of this species associated with Phylloceras ramostcm
Meek and P. ono'ense Stanton in the Lower Chico beds of
Arroyo del Valle, Alameda County, California.

Lytoccras argonatitaj-tim, as Gabb has stated, is the
largest ammonite known from the Cretaceous of California.
The name is proposed in honor of the " argonauts " and
gold-seekers of the pioneer days of California and the
Pacific Coast. This gigantic cephalopod appropriately
commemorates the motive and heroic spirit of these sturdy
and brave adventurers who so often struggled with hard-
ships even greater than those described in traditionary
history.

iPal. Cal., Vol. I, p. 67; Vol. II, p. 132.

Geol.— Vol. II. ] ANDERSON— CRETACEOUS DEPOSITS. 87

26. Lytoceras (Gabbioceras) angulatum, sp. nov.

Plate VI, Fig. 139.

Ammo7iites batesi (pars.) Gabb, Pal. Cal., Vol. II, p. 132, Pis. XX and XXI,

figs. 9 and 10, 1863.
Gabbioceras batesi Hyatt, Phylogeny of an Acquired Characteristic.

One of the species which was believed by Gabb to be
only a variety of Ammonites batesi has below the diameter
of 3.8 cm. a strongly angular section. There are few who
will maintain the identity of these species even upon an
inspection of Gabb's figures.

In the collections of the Universit}'' of California are three
well preserved examples of this shell, from which the draw-
ing (fig. 139) was made. One of the specimens has the
aperture complete, though crushed. It has been restored
in the figure. The shell does not apparently attain a large
size. Two of the specimens seem to be mature and are
less than three inches in diameter.

The involution of the shell is considerably greater than
either of the preceding species which Gabb included under
the name Ammonites batesi. The body-chamber, which in
these specimens occupies almost a complete whorl, is crossed
superficially by a few moderately strong, transverse, sinuous
grooves not evenly distributed. The shell between these is
polished, though marked with a few fine lines which bend
gently backward within the umbilicus.

The shell increases rapidly in size after losing its angular
character at a diameter of one inch or less.

Occurrence. — The stratigraphical position of this species
can not be given with certaint}'. The specimens are all
labeled " Cottonwood Creek, Shasta County." They are
probabl}" from the Horsetown beds of that region.

27. Hamites ellipticus, sp. nov.

Plate III, Figs. 102-103; Plate X, Fig. 191.

Shell compressed, elliptical in section, more narrowly rounded upon the
ventral or siphonal side than upon the dorsal; surface ornamented with sim-
ple and narrow transverse ribs separated by wider, rounded grooves; no

88 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

nodes or tubercles shown; suture line complex, consisting of six lobes and
six saddles, each bifid, and showing the same tendency in all of the smaller
divisions; both lobes and saddles widely branching, the former terminating
in sharp denticular points, while the latter become more rounded in their
terminations. The siphonal lobe is bipartite, with diverging branches, each
of which is further divided, and above which is a smaller, secondary spur or
branch. The antisiphonal lobe is more simple, consisting of an elongated
and irregularly toothed neck, tripartite in its termination. The first lateral
lobe is wider, though not quite so long as the second, and more regularly
divided. The second lateral saddle is both broader and higher than the first
one, and in its location occupies the middle of the rounded side. A single
constriction is to be seen upon the fragment found, though it is not clear that
this is not accidental. It consists of a broad and flattened depression (7.5
mm. in width) upon the sides and ventral edge, which is not altogether regu-
lar in its form. In front it is bordered by an oblique, rounded constriction
one millimeter wide, against the posterior side of which terminate four or five
of the preceding ribs. The succeeding ribs are thus set at an angle which
places them not quite parallel with those preceding this broad depression of
the sides.

Occurrence. — Forty-nine Mine, near Phoenix, Oregon.
The type is in the California Academy of Sciences.

28. Hamites phoenixensis, sp. nov.

Plate III, Fig. 104.

Shell small, cylindrical in section, bent in one plane into a hook-like curve;
surface ornamented with slightly oblique, transverse ribs inclining a little
forward in passing from the inner to the ventral side of the whorl; ribs a
little stronger on the ventral than upon the dorsal side, some rising consider-
ably above the rest in approaching the ventral surface; whorls crossed at
intervals by small rounded constrictions, not distinctly shown in the figure.
The ribbing is not (juite regular in the vicinity of the reflex curve, and there
seems to be a slight deviation from a true plane in this portion; and this seems
to be still further indicated by the ribbing, which is not quite symmetrical at
this point.

The septation of this species is not known. In its form
and sculpture, except for its lack of tubercular ornamenta-
tion, it resembles Hamites royerianus d'Orbigny, which is
said to come from the Neocomian of Europe; and in all
respects except size it resembles H. cylindraceus, as figured
by Whiteaves, from the Sucia Islands. It may be a small
representative of this western species.

Occurrence. — This species is from the Lower Chico beds
of the Forty-nine Mine, near Phoenix, Oregon.

The type is in the California Academy of Sciences.

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 89

29. Hamites cylindraceus de France.

Hamites cj/hidraceus {d'Orb.) de France, Pal. Franc, Vol. I, PI. CXXXVI.
ScHLUTER, Paleontographica, Vol. XXI, p. 103, PI. XXXI. ? not //. cyl-
indraceus (de France) Whiteaves, Canada Geol. Sur., Mes. Foss.,
Vol. I, 1876-S4, p. 113, PI. XIV.

Among the fossil cephalopods collected in Southern
Oregon is one that closely resembles //. cylindraceus, as
figured by Schlliter (1. c), belonging to the Upper Creta-
ceous of Europe. The suture line is not visible on any of
the specimens collected, but in their superficial features
they agree too nearly with the European species to justify
any other determination.

Shell not large, nearly cylindrical in section; elongated in the later portion,
straightened and recurved into a hook-like bend with two parallel arms; sur-
face crossed by simple annular ribs which are usually oblique to the axis,
without nodes or noticeable irregularities, except in direction. Some of the
ribs show a tendency to arrange themselves in planes perpendicular to the
axis of the shell, but the inclination is generally forward on the siphonal side.
The ribs are narrow and ridge-like, and separated by furrows which are
rounded on the bottom and at least twice as wide as the ribs themselves.
The diameter of the body-chamber in the largest specimen obtained is about
1.7 centimeters. All the specimens lack the band-like constrictions seen on
the species described by Whiteaves from the Sucia Islands.

30. Hamites armatus, sp. nov.

Plate V, Figs. 130-132.

Shell of medium size, attaining a greater diameter of about 20 mm.; ellip-
tical in cross-section; surface ornamented with regular rounded ribs inclining
obliquely forward; body- whorl crossed by strong constrictions about 30 mm.
apart, between which there are about twelve or thirteen parallel ribs; every
fifth or sixth rib armed near the siphonal line with two widely diverging
spines, attaining a length of 6 or 7 mm. ; the intervening ribs also armed but
with shorter spines. The area between each pair of longer spines is some-
what flattened, and marked by a narrow oval, especially when two of the
ribs coalesce to form the spine-like tubercles. The septum of this extra-
ordinary species is not yet known, but it is probably sufficiently well
characterized.

Occurrence. — This shell was found in the Lower Chico
beds near Henley, Siskiyou County, California. It was
found associated with Pachydiscus henleyensis, Desmoceras

po CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

siigatiim^ Placenticeras californicitm, P. pacijicicm, and
other Lower Chico forms.

31. Hamites (Ptychoceras) aequicostatum Gabb.

Ptychoceras cBquicostaticm Gabb, Pal. Cal., Vol. I, p. 74, PI. XIII, fig. 20;
Vol. II, PI. XXV, figs. 20, e and /. '^o\. Helicancylus cequicostatus Gabb,
Pal. Cal., Vol. II, p. 141, PI. XXV, figs. 20, a-d.

Ptychoceras ceqtiicostatuni , as originally described by
Gabb, is a true representative of this genus, and usually
not difficult to recognize as such; it is not uncommon in
the Upper Cretaceous beds of Shasta County.

On the larger branch of the shell the transverse ribbing is rather heavy,
and without ornamentation; the ribs themselves are high and narrow, the
intervening spaces rather broad and concave. On the smaller branch the
ribs are much less prominent, and the intervening spaces correspondingly
shallow; many of the ribs, at least, are ornamented with lateral, mammillary
tuf)ercles. Between tlie ribs which are so ornamented there are subordinate
ridges that appear to be simple; and with these there are also subordinate
striations.

These markings can be detected on Gabb's types and on
other examples which are among the collections of the
University of California.

In Gabb's revised description of this species ' quite another
genus (which Zittel refers to L.indigia, with some doubt)
has been confused with this species, and both are placed in
the genus Hclicancylus.

32. Hamites (Ptychoceras) solanoense, sp. nov.

Plate IX, Fig. 184.

Shell of moderate size; smaller branch of the type 15.5 cm. in length, with
an average diameter of 14 mm. ; tapering very gradually from small end to
the recurved portion; surface marked by regular, simple, and rounded trans-
verse ribs which are almost without ornamentation. There are seventy-five
of these ribs on the whole length of the small branch, evenly distributed
throughout. The only ornamentation noticed on these ribs are rows of very
faint tubercules on the ventral surface, on either side of the median plane,
most noticeable near the curve. On the dorsal side, which is somewhat
flattened, the ribs are nearly suppressed. On the recurved portion they are
also apparently less prominent.

li'al. Cal., Vol. II, 1863, p. 141. See also Lindigia ? nodosum, this paper, page 92.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 91

Occurrence. — The type of this species is in the collection
of the University of California. It was obtained from the
Cretaceous beds near Vacaville, Solano County, California,
by Mr. F. A. Steiger.

33. Helicoceras indicum (?) Slol.

Plate III, Figs. 96-97.

cf. Helicoceras indicum Stol., Pal. Ind., Vol. I, p. 184, PI. LXXXVI.

Shell small, coiled in a spiral, first to the right to a diameter of .7 cm. and
then reversed; section of whorls at first nearly circular, but afterward ellipti-
cal; surface marked by oblique transverse ridges not quite evenly spaced,
also by three or four constrictions. Diameter of spiral, 2 cm. ; septation
unknown.

Occurrence. — A single specimen was obtained from the
Smith ranch, two and one-half miles southwest of Phcenix,
Oregon, and belongs to the horizon of the Lower Chico.

The type here described is in the collection of the Cali-
fornia Academy of Sciences.

34. Heteroceras ceratopse, sp. nov.

Plate III, Figs, ioo-ioi.

Shell elliptical, or subcircular in section, very helicoid, forming widely open
coils in mature age; coiled sometimes toward the right and sometimes toward
the left, and therefore neither in one plane nor in a regular spiral; surface
ornamented with numerous transverse striations intervening between much
larger and elevated ridges that rise abruptly from the surface of the shell at
intervals of a few millimeters. These ridge-like ribs begin upon the dorsal
side in elevations hardly distinguishable from the intervening striations, and
as they pass downward on the sides they become more and more elevated,
until on the siphonal side they are often i mm. in height. They are rarely
well enough preserved to show their exact character, but appear to be pointed
or tuberculated along their thin blade-like summits.

The average diameter of the specimens collected ranges from .5 cm. to
I cm. The largest fragment has a length of 7 cm. All the fragments show
a tendency to curve irregularly and to depart from a simple spiral. Tiie
suture line is complex, consisting of bifid lobes and saddles; the lateral
saddles show a tendency to tripartite division in their main branches, while
the lobes retain their bipartite character throughout. In general form and
ornamentation this species resembles very closely Heteroceras reussianuin
d'Orbigny, as figured by Schliiter in " Paleontographia " (Vol. XXI, PI.
XXXII), to which it may be related.

92 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

Occurrence. — Found at the Smith ranch, east of Phoenix,
Oregon.

Type in the CaHfornia Academy of Sciences.

35. Lindigia ? nodosum, sp. nov.

Helicancylus ccquicoslatiis Gabb, Pal, Cal., Vol. II, p. 141, PI. XXV, figs.
20, a-g.

Zittle refers this species doubtfully to the genus above
given, which he has placed as a subgenus under Turrilites.
Gabb figured the type of this species under the name Heli-
cancylus. His description needs no special revision, except
that the tuberculation is not sufficiently pronounced either
in his figures or his description. On the larger coils of the
spiral portion these tubercles are large and circular in
section, or slightly elongated, and abruptly truncated at
the top.

Occurrence. — The type in the collection of the University
of California is labeled, " Cottonwood Creek, Shasta
County, California."

36. Baculites fairbanksi, sp. nov.

Plate VII, Figs. 152-153; Plate X, Fig. 194.

cf. Baculites vagina Forbes, Trans. Geol. Soc. Lond., 2d Ser., Vol. VII,

1845-56, p. 114.
cf. Baculites vagina Forbes, in Stein., Neu. Jahrb. f. Min., etc., Beil.-Bd. X,

1895-96, p. 89.

The largest specimen is a fragment about 11. 5 cm. in length, and in largest
diameter 1.5 cm. It is coarsely ribbed with strongly bent costa;, and shows
distinct lines of growth. The section is ovate but does not show the narrow
ridge along the siphonal edge as the figures of B. vagina appear to require.
There is a depression a little below the middle of the side which may repre-
sent it, however. There is a much closer resemblance found in the suture,
which is composed of broad, bifid saddles and narrow lobes, also somewhat
equally divided. The bifid or bipartite character is noticeable even in the
smaller divisions of both lobes and saddles.

This species is only distantly related to B. chico'cnsis
Trask, but shows more affinity with the form described by

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 93

Meek under that name; yet Meek's species is smooth while
this one is costate, and there are some differences to be
seen in the septation. Neither does it agree with the cos-
tate variety of Gabb, which is that usually found near
Martinez.

It appears remarkable that the widely distributed species
of cephalopod, Baculites vagina, has not been recognized
in the California Cretaceous deposits. It occurs both in
Southern India and on the west coast of Chile, and ought
to be found in the rich deposits of California, Oregon, and
British Columbia. Perhaps the nearest approach to it is
the above named species, brought from Orange County,
California, by Dr. H. W. Fairbanks. There is certainly a
very near relationship between the forms from Quiriquina
Island and the Santa Ana Mountains of Orange County.

Occurrence. — This species is found associated with many
Lower Chico fossils near Silverado Canyon, in the Santa
Ana Mountains of Orange County, California. It occurs
along with Anchura calif ornica, Actmonella oviformis,
Pholadomya anadna, and Chione varians.

Desmoceras.

In the middle Cretaceous of California, forms of Desmoc-
eras belonging to the group D. plamilatiini are numerous.
Four or five types have been recognized that are capable of
specific discrimination, some of them having ver}'^ strong
resemblances to Atlantic forms, such as D. mayorianum
d'Orbigny.

Among the members of this group is Desmoceras hoff-
manni Gabb.^ Gabb seems not to have recognized evident
differences among them and accordingly classed all under
one species, which does not appear to be justified. More
than twenty fairly well preserved specimens of this group
in the collections of Stanford University and the University
of California may easily be divided into three subgroups.
There can hardly be a doubt as to the distinctness of two

1 Pal. Cal., Vol. I, PI. XI, not Vol. II, PI. XX.

94 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

of these types, and probably the other is as deserving of
recognition. All of them range in diameter below 12.7 cm.,
while some of them are considerably smaller, ranging down
to the diameter of 2.5 cm. Some of the specimens in the
collections of the University of California still retain the
original labels attached to them by Gabb or other members
of the State Geological Survey.

The four succeeding types belong to the group
D. -planu latu ni .

37. Desmoceras hoffmanni Gabb}

Plate V, Figs. 120-123; Plate X, Figure 203.

It is not easy to determine which of the several forms of
this group should bear the name proposed by Gabb. The
species described in Vol. II of the Paleontology of Cali-
fornia, and figured on Plate XX, which seems to belong to
another type, has not been thus far identified.

In the collections of the University of California are
several specimens of a comparatively compressed shell,
some of which bear the name D. hoffmanni, and appear to
be referable to this species, except that the umbilicus is
somewhat narrower. Gabb states that in D. hoffmanni the
umbilicus has a diameter nearly equal to half that of the
coil. The six specimens here referred to this species have
a quite constant ratio between these measurements of 3.1:1,
the umbilicus being measured just inside the angles, or
shoulders. In the cross-section of the whorl they agree in
the main with Gabb's figure," though some of them are
relatively thicker. The number of constrictions does not
exceed seven or eight, though they are not regularly
disposed. The suture agrees in only a general way with
Gabb's figure, which is evidently defective. His descrip-
tion of the suture seems better, though it also is unsatisfac-
tory. The suture line consists of a siphonal and several

iNoTE. — This species has been selected by Alpheus Hyatt for the type of a new
genus, Pleuropachydiscus of the family Silestidce (Eastman's Translation of Zittel's Paleon-
tology), but there is no apparent reason for such a classification, and paleontologists
who are most familiar with this species will probably accept it with hesitation.

-'Pal. Cal., Vol. I, PI. II, figs. I3-I3a.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 95

lateral lobes, diminishing quite regularly in size from with-
out inward. On whorls of a diameter of 10.2 cm. there are
five of these lateral lobes which are unequally tripartite, so
much so, in fact, that they might almost as appropriately be
called unequally bipartite. The saddles are bifid, though
they have not the terminations shown in Gabb's figure.
Both lobes and saddles are moderately broad in their trunk
portions, the lobes regularly so; the terminations of the
lobes are digitiform, those of the saddles more or less
broadly scolloped. The involution of the whorls is more
than one-half and is, in one specimen, nearly two-thirds.

Ocatrrence. — This species is found in abundance along
Cottonwood Creek, Shasta County, California, in the upper
portion of the Ilorsetown. It occurs also at Horsetown
itself.

38. Desmoceras lecontei, sp. nov.

Plate III, Figs. 94 and 95; Plate X, Fig. 190.

Shell moderate in size, discoidal, flat, and rather involute; diameter of the
largest specimen found, 8.5 cm.; greatest thickness, 2.75 cm.; ratio of the
diameter of umbilicus to height of coil, 1:4; section of the whorl quadrate,
narrowing slightly toward the periphery; umbilicus narrow, but not deep, the
walls abrupt on each whorl, the inner coil forming a flattened ledge; ventral
surface rounded or slightly flattened; sides and surface of shell ornamented
with radiating, flexuous ribs which bifurcate a little above the middle of the
side on some specimens, and branch into three or more divisions on others;
ribs at first inclining forward, then backward, and finally forward upon
approaching the ventral region. In the more finely sculptured specimens of
this species the ribs are rather closely crowded together, while in others they
are as much as 2 mm. apart. Both ribs and interspaces are rounded. The
ribs do not continue across the ventral surface as a rule, but there are occa-
sional thickened ridges, probably of the nature of varices, upon this surface,
occupying the position of about each eighth or tenth rib.

In Gabb's species, as figured in Pal. Cal., Vol. II, PI. XX,
the ratio of the width of umbilicus to height of coil is i : 3,
the umbilicus being relatively wider than in D. lecontei.
The figure shown in Pal. Cal., Vol. I, PI. X, has even a
wider umbilicus, and truthfully represents the specimen
from which it was drawn. In Gabb's species, furthermore,
the ribs are coarser, and the specimens do not show the
varices on the ventral surface, clearly seen in D. lecontei.

96 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

Some specimens collected at Horsetown that are possibly
referable to this species have a diameter of 15 centimeters
or more.

Occurrence. — The type of this species was found in the
Horsetown beds a little to the east of Hulen Creek, Shasta
County, California. It is in the collections of the University
of California.

39. Desmoceras subquadratum, sp. nov.
Plate IV, Fk;s. 118-119; Plate X, Fig. 193.

Shell only moderately compressed; width of whorl nearly ecjual to depth;
umbilicus not so wide as in last species, ratio of whole diameter to umbilicus,
3.5:1; section of whorl subciuadrate; umbilical wall abrupt, broadly rounded
on the back; surface of the cast nearly smooth, showing none or only faint
constrictions; surface of shell marked by fine lines of growth and occasional
varex-like ridges that form the flexures commonly seen on the shells of this
group, bending more strongly forward in crossing the periphery; suture
characterized by stout lobes and saddles, lateral lobes four or five in number
on shells 7.5 cm. in diameter, decreasing uniformly in size toward the interior;
first lateral lobe nearly equally tripartite, the others less so; saddles nearly
equally bifid, with rounded terminations; width of shell increases with growth
more rapidly than the depth.

This species is possibly one figured by Gabb in the Pale-
ontology of California (Vol. II, PI. XX) as Desmoceras
hoffmanni (Pal. Cal.,Vol. II, PI. XX).

Occurrence. — This shell is not uncommon in the upper
portion of the Horsetown of Cottonwood Creek, Shasta
County, California, near the mouth of Hulen Creek. Four
of five good specimens were obtained at this place, some
of which are in the collections of the University of
California.

The types of this and the preceding species, as here
described, are in the collections of the University of
California.

40. Desmoceras colusaense, sp. nov.

Plate V, Figs. 128-129; Plate X, Fig. 10a.

In the collections of the State Mining Bureau in San
Francisco is a magnificent example of a Desmoceras of the
group D, flanulatiim^ nearly one foot in diameter. It is in

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 97

perfect state of preservation though broken so that it can
be taken apart, revealing the inner coils.

The shell is discoidal and somewhat compressed when small, but increases
in thickness very rapidly with growth; width of full grown whorl somewhat
less than the depth; ratio of diameter to width of umbilicus, 3.3:1; walls of
umbilicus rounded and sloping; section of whorl oval, sloping on the sides
toward the periphery; surface ornamented by transverse, rounded ridges
with the customary flexure, bending sharply backward within the umbilicus,
and forward in crossing the ventral surface. On the younger coils about ten
or eleven grooves are to be seen extending parallel to the lines of growth,
and are plainest upon the ventral surface. The involution covers nearly
two-thirds of the inner coils. The distinguishing features of this species are:
(i) the oval section of the whorl; (2) the rapidly increasing thickness of the
sliell after attaining a diameter of three or four inches; (3) the absence ot
constrictions which appear on most of the species of this group; and (4)
sutural characters. The suture of this species resembles in most points that
of Desmoceras hoffmaimi, yet there is at least a specific difference which
only a comparison will make clear. These dififerences are to be seen in the
siphonal saddle, the divisions of the lateral lobes, and in the regularity of the
small digitations on the lobes. There is less uniformity in the forward
terminal limits of the saddles than appears in the figures.

Occurrence. — This species evidently belongs to the
Horsetown horizon. It was obtained from the Peterson
ranch, in the vicinity of Sites, Colusa County, Cahfornia, a
locality not yet very well known, and was found associated
with Lytoceras batesi and other Horsetown species.

41. Desmoceras dilleri, sp. nov.

Plate IV, Figs. 116-117; Plate X, Fig. 192.

Shell discoidal, but not compressed; umbilicus wide and shallow, walls
rounded but abrupt, broadly rounded on ventral surface; ratio of greater
diameter to width of umbilicus 2.5:1; width of whorls equal to depth; invo-
lution a little less than one-half, that is covering less than one-half of the
inner coils; surface marked by slightly flexuous lines of growth and about
six shallow, transverse grooves which bend but little forward in crossing the
ventral surface; sides of whorl slope somewhat rapidly toward the periphery.
Suture line not minutely divided; both lobes and saddles rather broad; lobes
not equally tripartite, saddles bifid.

Occurrence. — Specimens of this species were obtained
from near the mouth of Hulen Creek, Shasta County,
Cahfornia. It belongs, therefore, in the upper part of the
Horsetown horizon.

The type is in the collections of the University of
California.

98 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

42. Desmoceras sugatum Forbes.

Plate III, Figs. 98-99.

Ammonites sugata Forbes, Trans. Geol. Soc. Lond., 2nd Ser., Vol. VII,
1S45-56, p. 113, PI. X. Stoliczka, Paleont. Ind., Vol. I, p. 60,
PI. XXXII.

Desmoceras sugata Yokoyama, Paleontographica 34, p. 185, PI. XX.

Among the interesting species comprising a small collec-
tion of fossils from Shasta Valley is an undoubted repre-
sentative of Amviomtes sugata, as described and figured by
Stoliczka. The author had not access to the original de-
scription of Forbes, and can only judge of its identity with
the Indian species, trusting to the accuracy of Stoliczka's
determination. The well preserved specimens from Siski-
you County show clearly all the characteristics of the
Indian type, and leave no room to doubt the essential
identity.

The shell is discoidal, very involute, smooth, flattened upon the sides,
keeled, and with narrow and deep uml)ilicus ; the keel is less noticeable
upon the younger portion of the coil ; one or two faint flexuous grooves are
seen near the aperture, bending considerably forward upon the ventral side.
The suture line consists of many lobes and saddles, six of each being visible
upon one side of the whorl and showing well their peculiarities ; saddles
bifid, with ultimate divisions rounded ; lobes trifid, with numerous pointed
denticles. The greatest diameter of the type specimen, which is probably
not an old one, is 2.7 cm. On a portion of the outer whorl, in which the test
is preserved, are faint lines of growth which curve strongly forward in cross-
ing the keel, indicating that the aperture had upon its ventral margin a long
projection or rostrum. These lines show also upon the cast of the shell, but
more faintly.

Ocair7'encc. — According to Stoliczka, Ammonites stigata
occurs in both the Arrialoor and Trichinopoly groups of
Southern India; Yokoyama reports it from a similar hori-
zon of Japan; and in California it occurs in the Lower
Chico beds of Siski3^ou County, from which the present
specimens were obtained. At Henley, four specimens of
this species were obtained along with Placenticeras calif or-
nicum, P. facificiim, and very many others of the Lower
Chico.

The type is in the collections of the California Academy
of Sciences.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 99

43. Desmoceras jugalis Gabh.

Ammcmites jugalis Gabb (in part), Pal. Cal., Vol. II, p. 133, PI. XXII, figs.
12, 12a and lib; not figs. 13 and 13a, same plate.

Perhaps no other CaHfornia species has caused so much
perplexity as Ammonites jugalis Gabb. In the Paleon-
tology of California, three species are figured and referred
to Ammonites jugalis. In the collections of the University
of California were found eight small specimens in one tray
labeled ^^ Am. jugalis Gabb," each with a label indicating
its locality. One, the type of fig. 5, Plate X, Vol. I, is a
typical Phylloceras ramosum Meek from the north side of
Mount Diablo. Another, labeled "Pioche's Coal Mine,"
perhaps near Mount Diablo, is clearly a crushed specimen
of sea-urchin, and has been recognized by Dr. J. C.
Merriam as an example of a species recently discovered
in the Martinez Group, and to which he has given the
name Schizaster lecontei. This is apparently the speci-
men from which Gabb' claimed to have drawn figs. 5 and
6h^ which doubtless represent two distinct species of
Ammonites. Of the other specimens, five are perhaps
from Curry's, on the south side of Mount Diablo, and
belong to a distinct genus, Schluteria, mentioned in
another part of this paper, and the remaining one is a
small crushed specimen of perhaps the same genus from
Martinez. The species figured in the Paleontology of Cal-
ifornia (Vol. II, PL XXII, figs. 12, 12(7, lib), should be
selected as representing the type of Ammonites jugalis, and
this is apparently the conclusion arrived at by Stanton
(1895-96, p. 1031), who has studied the species carefully.
There can be little doubt that figs. 13 and 13^^ are from
a species not yet recognized, which is distinct from Am-
monites jugalis. This is plainly seen in the sections and
surface markings, as shown in the figures.

1 Pal. Cal., Vol. II, p. 134.

2 Pal. Cal., Vol. I, PI. X.

^ Pal. Cal., Vol. II, PI. XXII.

lOO CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Sek.

44. Desmoceras voyi, sp. nov.
Plate III, Figs. 89-90.

In the collections of the University of California are
three specimens of a Desmoceras, each of a diameter of
about 5 cm., two of which belong to the " Voy collection,"
and are labeled "Cottonwood"; the third is from the
North Fork of Cottonwood, near Ono, Shasta County,
California, where it was obtained by the writer.

The general form is discoidal, though somewhat inflated; thickness of the
specimens, about 2.5 cm., umbilicus narrow and deep, rounded on the
ventral surface, toward which the sides gently converge; surface marked by
many fine lines of growth which are flexuous and parallel to the six trans-
verse grooves. These grooves are bordered behind by a ridge upon the
shell, while they themselves are to be seen only, or ordinarily, upon the
cast. The ridges become more prominent upon the periphery, where they
bend strongly forward, forming a projection at the border of the aperture.
The section of the whorl is elliptical in specimens of this diameter, though in
the younger shells it is more nearly circular. The involution is deep, em-
bracing more than tliree-fourths of the preceding whorl. The suture is a
true Desmoceras suture, similar to that represented by d'Orbigny ' for Am-
viofiites lalidorsatus, to which this species seems to be related. The sec-
tional aspect, however, of Z>. voyi is much narrower than that of d'Orbigny's
figures. There are also some resemblances between this species and
D.jugalis Gabb;^ yet the differences will be seen to be greater than could
be admissible for an identity without unusual evidence.

Occurrence. — Desmoceras voyi belongs to the lower or
central portion of the Horsetown beds of the Cottonwood
section. Ammonites latidorsaUis Mich, is a species be-
longing to the Gault, though it has also been found in the
Ootatoor beds of Southern India, which are thought to be
of Cenomanian age.

45. Desmoceras ashlandicum, sp. nov.

Plate IV, Figs. 107-109; Plate X, Fig. 196.

Shell discoidal, compressed, not small, moderately involute, and coarsely
ribbed; section of the whorl elliptical, narrowing gradually toward the
periphery; umbilicus moderately large, and increasing more rapidly with

iPal. Franc, VoL I, PL LXXX.

s PaL CaL, VoL II, PL XXII, figs. 12, 12a and \ib.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. lOI

age; in young adult shells the walls of the umbilicus are abrupt, but are
more sloping in younger, and more rounded in older shells ; the involution
is moderate, one-half of each earlier whorl being covered. The ribs are
mostly simple, only a few showing a disposition to bifurcate near the
umbilical shoulders. Two-thirds or more of the ribs do not extend to the
umbilicus, but arise from the middle of the side, or near the periphery, and
cross the ventral surface, curving forward so as to produce an angle on the
median plane. In age the ribs mainly disappear, or are reduced to about
ten or twelve rounded ridges that are confined to the umbilical side of
the whorl. The external side is then rounded and smooth. The diameter
of the two largest shells found was about 25 cm.

This species seems to be somewhat related to Puzosia
darwini, as figured by Steinmann, from the Island of
Quinquina, The constrictions that are shown upon Chile-
an species, however, do not appear upon the casts of the
one from Oregon.

Occurrence. — Several specimens of this shell, one of
which is the type, were found four miles southeast of Ash-
land, Oregon. A similar shell that may belong to the
same species was found at the Forty-nine Mine in Southern
Oregon.

The type of this species is in the collections of the Cali-
fornia Academy of Sciences.

46. Holcodiscus, cf. H. theoboldianus Stol.
Plate V, Figs. 126-127; Plate X, Fig. 197.

In the Voy Collection at the University of California is a
beautiful, well preserved specimen of an Holcodtsctis that
very closely resembles the above species from the Tri-
chinopoly group of Southern India. It belongs to the type
of Ammonites incertus d'Orbigny, which comes from the
Lower Cretaceous of Europe. Its sculpture exactly agrees
with Haploccras cumshewaense Whiteaves, though its form
is rather thicker. In this specimen the ratio of width of
the whorl to height is about nine to one; in H. cumshewaense
the ratio is said to be little more than five to one.

The shell in the Voy Collection has a diameter of about 6 cm., which is a
little more than three times the width of the umbilicus. The umbilicus has
abrupt though not vertical walls, the involution exposes about one-half the
(8) December 12, 1902

I02 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

side of the earlier whorls, the surface is ornamented with numerous fine trans-
verse ribs which bifurcate about the middle of the side, or more often one-third
of the distance from the umbilicus to the periphery. The ribs extend down-
ward on the walls of the umbilicus, are only slightly inclined forward, and
but little flexuous. The last whorl is crossed by five rather deep and
rounded grooves, marking former positions of the mouth. These grooves
follow the direction of the ribs, yet from their posterior margin three or four
ribs arise at intervals and cross the periphery. This gives the constrictions
an oblique appearance, yet on their anterior side they are exactly parallel to
the next succeeding ribs. The grooves are bordered by ridges a very little
stronger than the ribs ordinarily, and the anterior one forms a sharp promi-
nence where it crosses the umbilical shoulder. The suture line is quite
complex, consisting of four or more bifid saddles, very finely divided, ter-
minating in rounded denticles, and diminishing regularly in size toward the
umbilicus. The trunk and branches of the trifid lobes are relatively wider
than the corresponding parts of the saddles, and terminate in pointed, finger-
like teeth. The auxiliary lobes have an oblique direction, and are relatively
wider than the main, or first lateral lobe. The suture line agrees very well
with Stoliczka's figure in the main, but the dissection of the saddle is more
complete.

Occurrence. — It is unfortunate that this interesting spe-
cies cannot be more definitely located than a general refer-
ence to Cottonwood Creek, Shasta County, California.
The sandy character of the matrix, however, suggests that
it probably comes from an upper horizon of the Cretaceous
section of that place.

47. Pachydiscus newberryanus Meek (not Gahh).

Ammonites newberryanus Meek. Trans. Albany Inst., Vol. IV, 1857,
p. 47; Bull. Geol. Sur. Terr., Vol. II, 1876, p. 367, PI. IV, figs. 3, 3a,
3<5. VVhiteaves, Mes. Foss., Vol. I, 1879, p. 109, PI. XIV.

Afnmonites fraterniis GhBH, Pal. Cal., Vol. II, PI. XXIII.

In the collections of the University of California are two
or three specimens of this species from Pence's ranch,
Butte County, California. These were carefully compared
with a typical specimen from the Sucia Islands, in the
Straits of Georgia, British Columbia, borrowed from the
collections at Stanford University.

The normal development of this shell is characteristic. In youth, at a
diameter of three to four centimeters, the section of the shell is almost circu-
lar, though involute to the extent of covering nearly one-half the earlier
whorl. The ribs are simple or obscurely bifurcated in part; half of them

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 103

arise from within the umbilicus and pass outward to the ventral side, while
some of them arise from tubercles upon the umbilical shoulders. About six
constrictions cross the outer whorl transversely, bordered by ridge-like ribs
behind. As the shell increases in diameter it becomes rapidly more dis-
cpidal, narrowing toward the ventral edge. The ribs curve more strongly
forward in approaching the siphonal margin, the tubercles upon the umbil-
ical shoulder become obsolete or indistinct, and the height of the whorl
increases considerably. The more inflated form of the young shell of this
species is probably represented by Gabb's species, Ammonites fraternus}

Occurrence. — The species belongs to the upper portion
of the Chico beds, having a wide distribution in this
horizon.

48. Pachydiscus merriami, sp. no v.
Plate VI, Figs. 135-138,
cf. Ammonites suciaensis Gabb (not Meek), Pal. Cal., Vol. I, PI. XXVII.

Shell robust, but little compressed, rounded on the abdomen, and with
small umbilicus; walls of umbilicus abrupt within, rounded upon the
shoulders, deep and somewhat funnel form; width of umbilicus less than
one-fifth the whole diameter of the shell; somewhat flattened upon the sides,
rounded broadly over the ventral surface, and very thick; surface marked
with about eight transverse, shallow grooves, which are seen only upon the
casts, while upon the shell itself there are as many rounded ridges that
border these grooves in front; ridges more prominent upon the ventral
surface and almost disappearing upon the sides; lines of growth distinct
between the ridges.

The measurements of the largest specimen found are: diameter, 9.7 cm.;
greatest thickness, 4.7 cm.; width of umbilicus, 1.7 cm.; depth of involution,
1.7 cm.; height of last whorl from umbilicus, 4.8 cm. The suture consists of
two principal and three smaller auxiliary lobes, diminishing rapidly in size.
Both lobes and saddles are much divided, the saddles consisting in their
final divisions of broadly denticulated digitations that are somewhat spatulate
in form. The terminal branches of the lobes are narrowly acuminate.
Shells of this species are nearly spherical at a diameter of i cm., with a
reniform section; the depth of whorl becoming proportionately greater with
age. In crossing the sides of the whorl the grooves curve at first gently
backward and then forward, and approach the median plane obliquely.

This species is probably the one which Gabb found
upon the Cottonwood, in Shasta County, California, and
referred to as ^. sticia'cnsis Meek. The figure in the Pale-
ontology of California,^ however, was drawn from a speci-

1 Pal. Cal., Vol. 11, p. 137, PI. XXIII.

2 Vol. I, PI. XXVII.

I04 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

men brought from Vancouver Island, and represents
neither A. siiciaensis nor A. tnerriami ; yet perhaps they are
related.

The type represented by Gabb's figure, however, has
actually been found in the Lower Chico beds of the
Oregon basin, at Henley, Siskiyou County, and is de-
scribed in the following pages as Pachydiscus henleyensis.

Occurrence. — Pachydiscus merriami belongs near the top
of the Horsetown horizon. Three samples, representing
successive stages in its growth, were obtained from the
Upper Horsetown beds of Hulen Creek, Shasta County,
California.

The types are in the collection of the University of Cali-
fornia.

49. Pachydiscus henleyensis, sp. nov.
Plate VIII, Figs. 165-166.

Ammonites sucia'ensis Gabb (in part). Pal. Cal., Vol. I, Pis. XXVII and
XXVI II.

Shell robust, inflated, section of whorl broader than high, being reniform,
the ratio approximately nine to five; the umbilicus narrow, with rounded
shoulders; surface crossed by low, rounded ridges flattening and growing
in number toward the ventral side; sides of young shell moderately even,
and rounded in section, but flattening with age and breaking up into broad
undulations which appear to arise with growth from heavier ribs placed at
intervals, hardly noticeable on shells below a diameter of 15 centimeters.
The suture line is well represented by Gabb's figure, the lobes being narrow
and exceedingly divided.

Gabb's figure of this species is from a specimen about
five and one-half inches in diameter, a size intermediate
between the two that are represented in the sections given
for P. henleyensis. The section published by Gabb is evi-
dently not accurately drawn, showing too great an involu-
tion. A correction of this error shows the section of
Gabb's specimen to be intermediate to those given here,
which were both drawn from one specimen at different
ages.

Occurrence. — Two specimens of this shell were found
at Henley, Siskiyou County, California, in the Lower

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 105

Chico beds of that place, the larger one being about thirty-
two centimeters in diameter, but not altogether perfect.

The types of this species are in the collections of the
California Academy of Sciences.

50. Pachydiscus sacramenticus, sp. nov.

Plate VI, Figs. 133-134; Plate X, Fig. 195.

Shell discoidal, not compressed, of moderate size; section of whorl sub-
elliptical, truncated at umbilicus, rounded sides sloping very gently to meet
rounded ventrum; umbilicus wide, walls sloping steeply, involution covering
one-half of inner whorls; surface marked by narrow, sinuous ribs curving
gracefully forward in crossing ventral surface, most prominent at two-thirds
distance from umbilicus to siphonal plane; ribs separated by wide grooves,
which do not extend to umbilicus, and diminish on ventral surface; minor
lines abundant between larger ribs; body chamber occupying two-thirds of
entire outer whorl, increases but gradually in size with age; ratio of umbilical
dimension to diameter thirty-three one hundredths; width of whorl eighty-
four one hundredths of depth; suture of large whorl not seen.

This shell Dr. Stanton thinks is a Pachydiscus, and
the suture, so far as it can be seen, agrees with that
determination.

Occurrence. — The species belongs apparently to the
upper portion of the Horsetown. The type was obtained
upon an east branch of Hulen Creek, Shasta County, Cal-
ifornia. Another smaller specimen, thought to be identical
with this one, was found at Horsetown.

The type of the species is in the collections of the Uni-
versity of California.

51, Sonneratia stantoni, sp. nov.

Plate III, Figs. 91-93. Plate X, Fig. 198.

Shell small, not often above a diameter ot 3.5 cm., discoidal, laterally com-
pressed and flattened; sides converging gently toward the periphery; ventral
surface rounded or subquadrate; umbilicus not large, less than one-third the
total diameter, generally funnel-form, owing to its sloping sides and the
increasing thickness of the shell; surface ornamented with about thirty
transverse flexuous ribs which usually cross the ventral surface and ter-
minate in about half as many distinct tubercules upon the shoulder of the
umbilicus. The ribs show a tendency to bifurcate from these ridge-like

Io6 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

tubercules, become considerably depressed upon the sides of the shell,
curve gently backward, and become more prominent and wider near the
outer margin, where the curve is again decidedly forward. The surface of
the shell, both on the ribs and in the intervening rounded hollows, shows fine
striations which are parallel always to the ribs. The suture line is simple,
consisting of a few broadly-rounded saddles and wide lobes having very
short branches. The saddles are but little indented, and are bifid with
rounded denticles and incisions. Lobes unequally tripartite.

There appears to be considerable variation in the shells
of this species, some of them being much more compressed
and nearly without ribs, while others simply lack the ribs
and retain their normal thickness. One specimen in
which this variation is extreme, in addition to being almost
without ribs or tubercules, has its septa so crowded
together as to render them nearly indistinguishable, which
does not seem to be true of the great majority of speci-
mens. Dr. T. W. Stanton, to whom some specimens of
this species were submitted, thinks it probably belongs to
the genus Sonneratia Bailey; and in recognition of the
valuable contributions he has made to the study of West
Coast Cretaceous, the above name for this abundant and
interesting species is proposed.

Occurrence. — This shell is common in the vicinity of
Horsetown, Shasta County, California, though it has not
been reported from corresponding horizons elsewhere. It
belongs, therefore, to the upper portion of the Horsetown
division of the Cretaceous.

The type of the species is in the collections of the Uni-
versity of California.

52. Stoliczkia dispar (d'Orb.) Stoliczka.

cf. Ammonites dispar d'Orb., Pal. Franc. Terr. Cret., I, PI. XLV.
Ammonites dispar (d'Orb.) Stol., Pal. Ind., Vol. I, p. 85, PI. XLV.

The many descriptions of d'Orbigny's species referred
to by Stoliczka have not been accessible for comparison,
but the identity of the Indian species with one in the col-
lections of the University of California from the Shasta
beds cannot be doubted. There is so close an agreement

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. lO/

in every particular that little hesitation is felt in stating the
identification. A quotation from Stoliczka's description is
applicable to the California species exactly. He says:
"The small tubercles on the edge of the back of the young
shell, the unequally longer and shorter ribs, the nodular
ribs on the back of the body chamber, the irregular evolu-
tion of this last chamber, the division of the septa," — all
these characters which have been recognized in the Indian
examples are clearly seen also in those from California.

Occurrence. — This species comes from the Horsetown
beds of Cottonwood Creek, Shasta County, California.

53. Acanthoceras compressum, sp. nov.

Plate IX, Fig. 1S7.

Shell small, compressed or discoidal; average diameter of adult shell about
4.5 cm., greatest thickness 1.5 cm.; height of whorl about twice the width of
umbilicus, which is about one-fourth the diameter of the coil; surface marked
by flattened and rather flexuous ribs, of which there are about thirty-two in a
complete adult whorl; ribs often considerably reduced in strength, especially
on the sides of the shell, and ornamented at each extremity with rows of
prominent nodes. Along the margin of the umbilicus these tubercles are
rather high and narrow, inclining forward, while at the ventral termination of
the ribs the prominent linear nodes are often parallel to the median plane
in their arrangement. A secondary row of tubercles, less pronounced in
appearance, occupies a position inside the marginal row, each one forming a
point from which the rib bends rather sharply forward. The ventral surface
is flattened or only slightly convex between the marginal nodes, and is gen-
erally crossed by faint undulations which are the continuations of the ribs.
The median row of nodes sometimes noticed in species of this genus does
not appear on any of the specimens of this shell.

A. compressum is no doubt very closely related to
Am. rhotomagensis (var. compressus) Stoliczka, and per-
haps might be included in that species with no greater
stretch of Stoliczka's definition; but there does not seem
to be sufficient reason to include all of his four varieties in
a single species, while at the same time other forms are
excluded. A. compressum has a near ally in a species
from the Lower Chico beds of Southern Oregon, referred
to Acanthoceras rhotomagense, which very probably belongs

I08 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

to the variety showing a median row of nodes upon the
abdominal surface, as shown in d'Orbigny's figures^ and
in some of Stoliczka's.^

Occurrence. — Acanthoccras corner essum is found in the
Lower Chico beds of the Santa Ana Mountains, Silverado
Canon, and at Bowers Canon, in Los Angeles County,
California.

The type was obtained from the latter locality by Dr.
Stephen Bowers of Los Angeles. It is at present in the
collections of the University of California.

54. Douvilliceras mamillare Schloth.

Acanthoccras mamillare Schloth, Pal. Franc. Terr. Cretac, T. I, PI.

LXXIII.
Acanthoccras mamillare (?) (Schloth) Stanton, Bui. Geol. Soc. Am.,

Vol. V, 1894, p. 445.
cf. Atnmonites mantelli (Sow.) Stoliczka, Pal. Ind., Vol. I, p. 81, PI.

XLII, figs. I and la.
Ammonites stoliczkamis (?) Gabb, Pal. Cal., Vol. II, p. 135, PI. XXIII.

In the upper Cretaceous beds of Clear Creek and the
Cottonwood Creek, Shasta County, California, this spe-
cies is somewhat common. It occurs here in beds evidently
quite similar to the Cenomanian, being found both in the
Lower Chico and the uppermost Horsetown.

Among the collections at the University of California are
a number of specimens of AiJimonites mamillare from
France, and a comparison of these with several well pre-
served types from Shasta County shows few differences,
and the very strongest resemblances, between them.
There is the same general form and ornamentation ; the
same width and depth of umbilicus, and involution of
whorls; the tuberculation on both is identical, and goes
through a cycle of development the same in both cases.

At a diameter of 2-3 centimeters (in the Shasta specimens) the ornamenta-
tion of the ribs consists of spinose tubercles in three rows. One of these
rows is upon tlie umbilical shoulder, one upon the ventral surface upon each
side of the median plane, and a third upon the middle of the side, where it

1 Pal. Franc. Terr. Cret., I, PL CV.

2 PaL Ind., VoL I, PL XXXIV.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. IO9

forms a sort of angle. These tubercles are not generally found upon all the
ribs, but are often upon only alternate ones. As the growth of the shell pro-
ceeds, these rows become series by the development of other secondary
tubercules that cause a doubling or trebling of the rows. This is more par-
ticularly so with the external row. At the diameter of 5 or 6 centimeters,
these tubercules appear to reach their maximum development and form
almost a continuous series from the umbilicus outward, which has its greatest
height upon the ventral side. Above this diameter they gradually decline in
prominence and at the diameter of 12 centimeters they become obsolete.
The form of the shell also changes with age and becomes less angular and
more rounded in section. The suture line consists of three saddles and two
lateral lobes with one or two auxiliary lobes and saddles within the umbilical
angle. The first lateral saddle is very prominent. The saddles are broad
and are not deeply incised, the lobes are unequally bifid, the longer division
terminating in a long, narrow digit with short branches and denticles.
D'Orbigny's figure represents this form quite perfectly.

The figures and description of Acanthoceras s^miferiLin'^
Whiteaves agree with this species perfectly as it occurs in
the California beds, and the differences between the
Queen Charlotte Island specimen sent to Kossmat and the
European species seem to be unimportant. In fact, the
features upon which the distinction is founded do not seem
to be constant for either the European samples, or those
obtained from California.

This shell is not uncommon at Horsetown and at Hulen
Creek, a few miles to the west.

Scaphites.

Until now the genus Scaphites has been all but unknown
in the Pacific border province of America, though it is well
represented both in the Cretaceous of Southern India and
in that of the upper Missouri, from either or from both of
which sources it may have been derived. It is therefore of
some interest to find at last within the limits of the West
Coast Cretaceous no less that six species of this shell so
characteristic of many marine Upper Cretaceous deposits.

In the rich fossil beds of Southern India this genus is
most abundant in the lower horizon, the Ootatoor, which
has been correlated with the Cenomanian of Europe. In

1 Mes. Foss., Vol. I, Pt. IV, p. 273, PI. XXXV.

no CALIFORNIA ACADEMY OF SCIENCES. [Proc. 30 Ser.

the upper Missouri beds it belongs to beds that are
regarded as Turonian in age. The members of the genus
that have been found in the Oregon basin are, at least in
two or three cases, closely allied to those of the upper
Missouri, with which they may have probably genetic rela-
tion.

55. Scaphites gillisi, sp. nov.

Plate III, Figs. 85-88.

It is only after considerable study and comparison that
this fine little Scaphite has appeared to be entitled to a
distinct specific name. There are in the collections of
the University of California five perfect examples of S.
warreni M. & H. from the Upper Cretaceous of Dakota.

In form and ornamentation the above species agrees so closely with
that from the upper Missouri that at first it seemed indistinguishable from
it except by its smaller size and generally smoother shell. The transverse
costae of S. warreni are not only sharper and stronger, but the lateral ridge-
like nodes are also more numerous and more prominent. In form S. gillisi
is more quadrate in outline, being at the same time proportionately longer
and narrower than the species of M. & H. As to the sutures in S. gillisi,
the lateral lobes are relatively wider and more developed; the first lateral
saddle is more deev)ly divided, and the siphonal lobe and its subdivisions
are both deeper and more strotigly incised. While in general the form of
the suture is very similar to that of .S". warreni, it is at the same time more
complex in detail.

There will hardly be a doubt as to the near relation of
the species S. gillisi and S . -warreni, and whether identical
or not it serves to strengthen the connection between the
deposits of the Oregon basin and those of the Colorado
group, in which the latter is found, and to ally them both
to the Cenomanian. S. gillisi is more distantly related to
S. csqualis Sowerby, and agrees fairly well with some of
the types figured by StoHczka,^ except that the shell is
thicker in transverse section, is more quadrate in outline,
and has simpler sutures. It lacks the peculiar ventricose
development of the body-chamber seen in d'Orbigny's
figures, though in other respects there is considerable

1 Pal. Ind., Vol. I, PI. I^XXXI, figs. 4 and 6.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. Ill

agreement. Meek also states a similar relationship for
S . luarreni.

The type is in the collections of the CaHfornia Academy
of Sciences.

Occurrence. — This species, with its associates, is from
the Upper Cretaceous beds of Shasta Valley, which in their
stratigraphic position correspond very nearly to the fossilif-
erous beds of the Forty-nine Mine, near Phoenix, in Roo-ue
River Valley, Oregon, and to the Lower Chico beds of
Shasta County and the upper Sacramento Valley, Califor-
nia. The name is proposed in recognition of the general
and intelligent interest taken in geological science by the
donor, Mrs. H. B. Gillis of Yreka, who has contributed
materially to the present study.

56. Scaphites condoni, sp. nov,

Plate II, Figs. 58-63.

Shell small, type specimen 2.5 cm. in length, r.6 cm. in width, moderately
inflated, especially at the recurved portion, where the section of the body-
chamber is almost circular; outline of shell subquadrate, inclining to oval;
surface ornamented by both ribs and nodes. The body-chamber is crossed
just behind the deflected portion by thick transverse ridges with intervening
constrictions, which are, however, confined to the sides of the shell and are
most prominent upon the middle zone, though extending to the umbilicus
and to the row of small tubercules bordering the ventral area. The posterior
part of the body-chamber is flattened upon the sides and forms a dorsal
expansion which almost covers the otherwise open umbilicus. The coiled
portion of the shell is crossed by numerous transverse, slightly curved ribs
extending from the umbilical border and branching a little below into two or
more divisions. Each of these branches terminates in a node upon the ven-
tral margin of the side, from which arise two or more finer ribs crossing the
ventral area. Upon the sides of the body-chamber these ribs do not appear,
except in the most posterior portion. The nodes upon the ventral shoulder
of the whorl first appear at a diameter of near i cm., becoming most promi-
nent upon the body-chamber. Along the ventral margin of its sides these
nodes show a tendency to become pointed or spinose tubercules which incline
outwards, forming a flattened ventral surface. From these tubercules, which
are triangular in form, originate small ridges, scarcely noticeable, which cross
the ventral portion of the body-chamber. Neither nodes nor ridges, how-
ever, are found upon the recurved portion of the shell. Back of the aperture,
which is partly closed by a strong constriction, is a conspicuous expansion or
thickening of the shell, forming a lip-like ridge surrounding the mouth. The

112 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

umbilicus in the younger coils is wide, the whorls being little involute and
almost circular in section. With increasing age the whorls become more
clasping, until at maturity the umbilicus is almost, though never entirely,
closed. The ribs form at a diameter of about .8 cm.

The suture line is simple, consisting of but few bifid lobes and saddles, the
latter of which are rounded in their smaller divisions, and in general outline,
while the former are narrow and pointed.

Occurrence. — This species was collected with the follow-
ing at the Forty-nine Mine, near Phoenix, Oregon. Its
horizon is equivalent to that of the Lower Chico of the
Sacramento basin.

The type is in the collections of the California Academy
of Sciences.

The species is named in honor of Professor Thomas
Condon of the University of Oregon. It is with pleas-
ure that a tribute of recognition is thus offered for the
deep interest and devotion to geological study which
has so often been a source of inspiration alike to students
and acquaintances.

57. Scaphites condoni var. appressus, sp. et var. nov.

Plate II, Figs. 64-66.

This shell is quite evidently a variety of the preceding,
and it will be only necessary to mention here its points of
difference.

In general it has a thinner and more compressed form. The transverse
ridges and constrictions upon the body-chamber are farther forward than
those upon the type of the species, and have, moreover, a decidedly obHque
tendency. The transverse ribs upon the coiled portion of the shell are
scarcely to be seen. The suture line seems to be a little more developed, or
complex, in its details, but otherwise is identical with that of the type.

Occurrence. — The position and occurrence of this shell
is the same as that of the preceding.

The type is in the collections of the California Academy
of Sciences.

58. Scaphites roguensis, sp. nov.

Plate II, Figs. 67-70.

Shell small, discoidal, flattened on sides, quadrate in section; umbilicus
small in adult shell, relatively wider when young; surface of shell nearly

Geol.-Voi.. II.] ANDERSON— CRETACEOUS DEPOSITS. II3

smooth on body-chamber, coiled portion crossed by many transverse costae;
ventral shoulders of body-whorl ornamented by small, oblique tubercules;
dorsal edge of body-chamber expanded over the umbilicus.

Length of shell, 2 cm.; width, 1.5 cm.; greatest thickness, .6 cm. Septation
unknown.

This shell is apparently related to the preceding,
though it has not the characteristic constrictions of that
species, and is more flattened on the sides.

Occurrence. — Found with the preceding in the Lower
Chico beds of the Forty-nine Mine, near Phoenix, Oregon.

The type of this species is in the collections of the
California Academy of Sciences.

59. Scaphites inermis, sp. nov.

Plate III, Figs. 74-77.

Shell small, compressed, elliptical in outline, smooth, and almost without
ornamentation. Umbilicus open and wholly uncovered; whorls litde invo-
lute, ne\^er clasping one-half the preceding whorl, and subcircular in section
throughout; body-chamber, however, a little deeper than wide though
quadrate; squared or truncated on the dorsal side. The sides of the body-
chamber are obliquely crossed by faint transverse, and apparently bifurcating
ribs, which continue uninterrupted across the ventral surface. On both the
umbilical and ventral shoulders of the body-whorl there are small linear
nodes that are almost obsolete on some specimens and hardly appear at all
upon the coiled portion of the shell; aperture having a ridge-like rim, hardly
a lip, surrounding it, behind which is a shallow constriction, both of which
curve backwards at the inner angle of the whorl. On each side of the aperture
a small auricular expansion extends forward from near the dorsal edge of the
mouth, forming a small triangular surface showing faint concentric strise.

It is thought worth while to note that upon one specimen,
which was accidentally broken, the "impressed zone" of
the body-chamber was well exposed. Although the body-
volution was entirely free from the earlier coil, this dorsal
zone, which had appeared to be squared or truncated, yet
contained, as far as the margin of the aperture, a shallow,
though distinct groove.

Occiirrencc. — This species is abundant at the Smith
ranch, and has been found also at the Forty-nine Mine,
near Phoenix, Oregon.

114 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

60. Scaphites perrini, sp. nov.

Plate II, Figs. ti~T2>-

The most remarkable species of Sca^phites that has been
discovered at localities in Southern Oregon was collected
recently by Dr. James Perrin Smith, in whose honor the
above name is proposed.

Unlike other known types of this genus, most of which are inclined to be
discoidal, at least in some stages, S. perrini seems to be at no stage either
discoidal or merely gibbous or inflated.

The shell is small, being little over 1.2. cm. in length, .9 cm. in greatest
width, and .65 cm. in greatest thickness.

The section of the whorls, though not entirely visible, seems to be trans-
versely elliptical, or "digonal" with each " lateral angle " forming the margin
of a funnel-form umbilicus. The ventral surface is broad, extending to the
umbilical angle, rounded, and nearly smooth. The aperture is reduced by a
strong, rounded constriction which extends a little beyond the umbilical
angles, and is bordered in front by a sharp elevation or ridge. From each
side of the aperture large lateral ears extend forward, almost touching the
lateral angles of the preceding whorl, and reducing the form of tlie aperture
to subquadrate. The surface ornamentation of this species consists of small,
simple ribs, which do not appear to cross the wide ventral surface, or else
cross it only as fine lines, not visible upon the cast. These ribs are most
conspicuous upon the lateral angles of the whorl, which they cross, forming
small nodes, from which they incline obliquely backward on both the um-
bilical and the external surfaces.

The suture line, which can be traced only across the rounded ventral
surface, is simple, consisting of broad saddles and narrow lobes, both of
which are bifid in their subdivisions. The siphonal lobe is simple, being
almost as wide as long, having one lateral and one terminal branch. The
first lateral saddle is quadrate in outline, and subdivided into two unequal
portions, which are again indented or divided in a similar manner.

Occurrence. — S. perrini is known only from a single,
though nearly perfect, specimen, obtained recently from
the Smith ranch, near Phoenix, Oregon, by Dr. J. P.
Smith, through whose courtesy the author has been per-
mitted to describe it. It is from beds that are equivalent
in their horizon to those of the Lower Chico of the Sacra-
mento basin.

The type is in the collections of the Leland Stanford Jr.
University.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. I15

61. Scaphites klamathensis, sp. nov.

Plate III, Figs. 78-81.

Shell small, compressed, ovate in outline, measuring only 1.3 cm. in length,
.9 cm. in width, and .35 cm. in greatest thickness. Umbilicus not wide;
whorls clasping generally about one-half of the preceding volution in youth
and apparently suppressing the umbilicus in age; section of whorls sub-
circular or subquadrate, flattened on the dorsal side of the body- whorl,
which is somewhat inflated in the region of the bend. The surface is orna-
mented with fine ribs or striations, which cross the ventral surface and con-
verge toward small nodes near the umbilical margin of the whorl. These
ribs are seen only upon the body-chamber, and the nodes appear only upon
the last two-thirds of the same. The suture is simple, consisting of a large
siphonal lobe and a very much smaller lateral one, with one or two sec-
ondary lobes. There is one lateral saddle upon the inner side of which is an
indentation that might pass for an auxiliary saddle.

The aperture of this species deserves special notice. It is bordered by a
distinct lip which is immediately preceded by a rather wide and shallow con-
striction which extends upward toward tUe dorsum without apparently
reaching it; from each side of the aperture a wing-like expansion extends to
the preceding coil, against which it rests, thus reducing the aperture to an
oval opening upon the ventral side of the shell. The surface of these expan-
sions are ornamented with concentric undulations that begin at the middle of
the mouth-border, i. e., at the middle of the side of the aperture.

In all respects except as to size and form of aperture,
S. klamathensis exactly agrees with S. larv<^formis M. & H.
from the lower portion of the Colorado group of the upper
Missouri. Meek and Hayden's figures do not show the
buccal border, and apparently it was not known. There
is reason to believe that S. klamathensis is only a small
form of S . larvcBforniis, but until this can be more satisfac-
torily shown, it seems preferable to designate the Shasta
Valley species by a separate name. It is also related to
S. I tier mis.

Occurrence. — This species is one from the small collec-
tion presented to the author by Mrs. H. B. Gillis of Yreka,
and comes from the northern border of Shasta Valley, to
the south of the Klamath River.

The type is in the collections of the California Academy
of Sciences.

Tl6 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

An important addition to the number of species of
SchlcBiibachta^ hitherto known from the West Coast will be
recognized in this paper. No less than ten distinct forms
have been found in the Chico beds of Northern California
and Southern Oregon. It is possible that with further
searching still others will be discovered, since each new
collection of them contains some new species not met with
before.

In the Lower Horsetown beds representatives of this
genus have not been found, but in the Upper Horse-
town is the Cenomanian species, S. injlata. In the Upper
Chico are S. chicoensis Trask, S. gahbi, sp. nov. and
S. buttensis, sp. nov. By far the larger number, however,
are found in the Lower Chico beds, and principally in the
Oregon basin. With the exception of a single species,
S. chicoensis, there is but little resemblance between those
of the two adjoining basins.

Most of the species described in this paper fall without
much question into the genera recognized by Zittel in his
later work.^ Four of the genera are represented by two
or more species each. There are other forms, however,
that admit of such grouping with more difficulty. In some
of them the keel entirely disappears in old age, or even
before mature age is reached.

62. Schlcenbachia chicoensis Trask.

Plate I, Figs. 21-22; Plate II, Figs. 23-25.

Ammonites chicoensis Trask, Proc. Cal. Acad. Sci., Vol. I, 1856, p. ^,
PI. II.

From a careful study of this species with others nearly
related, it is evident that there has been a confusion enter-
tained by some of the earlier writers upon the paleontology
of California. The figures and description of this species

^Schlcenbachia is used in this paper in the broad sense originally defined by Zittel in
his "Traits de Paleontologie," 18S7.

""Grundziige der Palreontologie," 1895.

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. II 7

b}' Gabb can hardly be made to agree with those of Trask
(1. c). The description of neither species can be consid-
ered satisfactory; yet enough is shown and told to make it
evident that two species, and not one, have been described
under this name.

In Trask's species there are about twenty-four distinct
and simple ribs, bearing a double row of tubercules near
the outer margin of the coil. The ribs do not bifurcate
upon the sides, but seem to consist of two kinds, primar}-
and auxiliary. The latter do not extend to the umbilicus,
but disappear a little above the middle of the sides, and
extend to the outer margin. No statement is made as to
the relative size of the umbilicus, but in Trask's figure it
appears to be more than one-third the diameter of the
entire coil. The section of the whorl is oval rather than
flattened, as in Gabb's species.

The specimen figured by Trask was probably an imma-
ture one, and there is room for a considerable change in
these features during a more complete growth; yet the
changes would hardly be of the nature which Gabb's
figures indicate. There is in the collections at Berkeley a
small specimen, labeled as coming from Trask's original
locality, which agrees tolerably well with his description
except in the number of ribs, which is slightly greater.
Trask's species also seems to be much less common than
Gabb's, or it has not been definitely recognized.

Occurrence. — Trask's specimens came from the Upper
Chico, on the eastern side of the Sacramento Valley, and
from the locality of Chico Creek, and Pence's ranch,
California.

63. Schloenbachia gabbi, sp. nov.

Ammonites chico'ensis Gabb (not Trask). Paleontology' Cal., Vol. I. p. 68,
Pis. XVIII-XIX.

In the collections of the University of California are

several well-preserved casts of Gabb's species of this shell

from the original localities of both Trask and Gabb. They

are identifiable without great difficulty from Gabb's figures

and description, with which they agree fairly well in most

points.

(9) December 22, 1902.

Il8 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

The larger shells are almost squarely truncated at tlie ventral margin, the
keel often being very slight, though always visible. The sides are flat-
tened or gently convex, and ornamented with about forty-five to fifty ribs
counted along the ventral margin, where they terminate in flat, transverse
tubercules. On the umbilical margin of the whorl there is a prominent row
of tubercules not shown in Gabb's figure, though mentioned in the text, from
which the umbilical wall makes a perpendicular descent. The costal nodes
are not always very conspicuous upon the casts, though three or four rows
can be distinctly made out.

The young shells of this species, unlike those of Trask's species, are
almost perfectly smooth, showing neither ribs nor costal nodes until they
attain a diameter of more than 2 cm. Gabb seemed lo have noticed this
fact, though without attaching to it the importance which it deserves. The
specimen figured by Trask had a diameter of 1.5 cm., yet distinctly showed
twenty-four strong ribs. In the young shell of Gabb's species the umbilicus
has a diameter of less than one-fourth that of the entire coil, and the section
of the whorl is narrow and elongated, and rather squarely truncated on both
dorsal an<l xenlral margins.

The largest specimens of S. gabbi in the collections of the University of
California have a diameter of 10 cm., and at that size the ribs have almost
disappeared, together with the nodes upon the sides of the sliell.

The above name is proposed to distinguish this species
from that for which it has evidently been mistaken. There
are some varieties of the species that deserve mention, one,
especially, in which the sides are more than ordinarily
convex, and in which the ventral truncation is somewhat
rounded.

64. Schlcenbachia buttensis, sp. nov.

Plate IV, Figs, no, in.

This species is related to S. gabbi, though it is evidently a distinct form.
The ribs, about fourteen in number, counted along the umbilical shoulders,
.are nodose and bifurcating. The nodes are in five rows upon the sides of
the shell, and in this respect it resembles its congener, .S. gabbi, but the
umbilical row is much more elevated and narrow, and the ribs are more
disposed to bifurcate. This takes place from either of the three inner rows
of nodes. The nodes of the outer row are sharp and ridge-like, forming
upon the periphery a flattened, ventral surface, as shown upon the cast. The
keel is low and apparently entire; septation not well known. 5". buttensis
is also related to S. varians Sowerby.

The figure was drawn from an imperfect specimen,
immature in size, 3'^et sufficiently large to show the specific
characters.

Geol .— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. II9

Occurrence. — The species is an associate of the preceding
one, S. gabbi, and belongs to the Upper Chico of Pence's
ranch, Butte Count}^ California.

The type is in the collections of the University of
California.

65. Schloenbachia siskiyouensis, sp. nov.
Plate I, Figs. 19-20.

Shell discoidal and compressed; umbilicus of young coils about one-
third the whole diameter, becoming relatively narrower v\ith increasing age;
keel at first simple, but at a diameter of i cm. begins to break up into nodes,
which at 3 cm. become entirely separated by moderately wide intervals. On
the older shells the segments of the keel form high and narrow tubercules
which have a definite and regular position with reference to the ribs. The
ribs are simple, about twenty-five in number, and are of two orders. The
first originate in the prominent tubercules along the umbilical margin of the
whorl, and, bifurcating from that point, terminate in the outer row of
tubercles along the ventral margin. The ribs of the second order make their
appearance between the pairs of the first. Thus, about every third rib
arises from a little above the middle of the side, without extending to the
umbilicus, and terminates as do the others, in the external row of tubercules.
This outer row of tubercules forms a series of distinct and pointed prom-
inences that diverge slightly from the plane of the keel. A little abo\e these,
upon each rib, is developed a distinct prominence which forms the thickest
portion of the rib, and which is separated from the outer, or marginal node,
by a shallow though visible depression. The ribs are inclined to be straight,
except where on approaching the outer margin they curve slightly forward.
The tubercules of the keel stand a little forward of the marginal nodes in a
position to meet exactly the forward curving of the ribs.

This, together with the following species, appears to be
referable to the genus Barroisiceras Gross. It seems to
have no close ally either in the deposits of Southern India
or in the Interior Basin of the United States.

66. Schloenbachia knighteni, sp. nov.

Plate I, Figs. 1-4; Plate II, Figs. 39-40.

Shell discoidal, compressed; sides flattened in young adult smaller coils,
but becoming more inflated in old age, attaining a diameter of 10 cm. ; surface
characterized by the possession of about thirty simple and almost straight ribs,
most of which originate at the umbilical margin of tlie whorl; one-third of the
whole number beginning there in prominent tubercules, the others arising

I20 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

below this line upon the sides of the whorl, but all extending to ventral mar-
gin, where they terminate in equally prominent tubercules. This outer row
of tubercules shows a tendency to doubling, which can be detected upon all
shells above a diameter of 1.5 cm., though shown most clearly upon coils
above a diameter of 4 cm. and below 7 cm. The ribs bend more obliquely
forward at the inner node of this double row, which is considerably less con-
spicuous than the outer one.

The ventral and dorsal margins have an abrupt truncation at maturity, and
above a diameter of 2 cm., but lose this character and become rounded in
old age, as they are in the very young stages.

The keel and ribs seem to appear together just below the diarneter of
3 mm., the ribs appearing first in the ventral region. The keel,. which is at
first simple, begins to show crenulations at a diameter of 1.5 cm.,, which
gradually increase in prominence until maturity. In the older portions of the
shell these again decline. ■ ;,•

The umbilicus of this shell is wide and shallow, occupying about one-third
of the entire diameter of the coil. Within the umbiHcus the thin, sharp ribs
and dorsal tubercules of the younger whorls are noticeable.

The sutures consist of a ventral and one lateral lobe, supplemented by two
auxiliary lobes near and within the umbilicus. The saddles show a tendency
to become bifid, though this division has actually been seen on only the first
lateral saddle. Tlie lateral lobe is simple and elongated, with relatively small
subdivisions, amounting merely to short teeth.

The name, S. knighteni, is proposed in recognition of
the kindly interest taken in this study by Mr. E, Knighten
Anderson, from whose property the larger part of this inter-
esting collection was obtained, and to whom the author is
indebted for first calling his attention to this important
locality.

The type is in the collections of the California Academy
of Sciences.

67. Schlcenbachia multicosta, sp. nov.

Plate II, Figs. 41-47.

Shell discoidal and compressed, umbilicus wide and shallow; moderately
involute, the outer whorl embracing about one-third, or less, of the inner
one; sides of whorl flattened, giving a narrow quadrangular outline to the
shell when viewed from behind; the sides ornamented with about fifty
oblique, flexuous ribs, which tend to bifurcate from tubercules occurring along
the inner margin of the whorl. The ribs curve forward in approaching the
outer margin of the whorl, and like the preceding species this one has a
double row of inconspicuous tubercules upon the ventral shoulders. The
ribs are generally rounded; the keel, which is simple and entire, lacks the

Geol— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 121

grooves noticed in the preceding species. In development this species is
very similar to the preceding, but differs from it considerably in the adult
shells. The essential differences are: (i) the narrower umbilicus of S. inulti-
costa; (2) the fle.KUous ribs, which have a greater tendency to form tuber-
cules upon the umbilical shoulders from which bifurcate the ribs; and
(3) the absence of the grooves along the sides of the keel. The whorls are,
furthermore, usually inflated in the younger forms.

Occurrence. — This species occurs abundantly at the
Smith Ranch, about two miles west of Phoenix, Oregon.
The horizon is that of the Forty-nine Mine, and is
the equivalent of the Lower Chico of the Sacramento
Valley.

The types are in the collections of the California
Academy of Sciences.

68. Schloenbachia bakeri, sp. nov.

Plate II, Figs. 26-33.

Shell discoidal, compressed, quadrilateral in section; umbilicus wide and
shallow, with rounded sides; keel prominent and entire, with slight grooves
along the sides; involution covering about one-third the inner whorl; sides
ornamented by about thirty-eight to forty-four simple, oblique ribs, which
are narrow and sharply angular, each extending from the inner margin of the
whorl to the keel.

The ribs form only small tubercules upon the umbilical margin of the
whorl, though a few of them become a little more prominent here, while
near the periphery a double row of inconspicuous nodes occurs. The ribs
bend sharply forward as they approach the keel, while seen from the side
they appear straight for the greater part of their length. They begin to
form uniformly at 3>^ whorls at a diameter of 3 mm.

Keel high and thin, with only faint undulations along its summit, some-
times not to be seen at all. The smallest coils of the shell are smooth,
without keel, and almost circular in section except for the impressed zone.
The keel begins to appear upon the third whorl at a diamet«r of between
2 and 3 mm.

The diameter of the largest specimen found is a little more than 3 cm.,
and this is probably the average diameter of adult shells. The body-
chamber occupies about two-thirds of the last whorl.

Although a number of otherwise perfect specimens of
this species were found, the suture of an adult shell was
not seen. As far as could be ascertained, it is similar to
that of the following species, S. oregonensis, to which it is
related.

122 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

The name proposed for this species is borrowed from
the frontier history of Southern Oregon, old Fort Baker
having stood within a short distance of the locahty from
which the type was collected.

Occurrence. — This shell is tolerably abundant at the
locality of the Forty-nine Mine, near Phoenix, Oregon, on
the horizon of the Lower Chico beds.

The type is in the collections of the CaHfornia Academy
of Sciences.

69. Schloenbachia oregonensis, sp. nov.

Plate II, Figs. 48-57; Plate VI, Fig. 144; Plate VII, Fig. 149.

Sehloenbachia oregonensis Anderson (M. S.), J. P. Smith, Jour. Morph.,
Vol. XVI, 1899, p. 10, Pis. A-E.

Shell discoidal and compressed, increasing in thickness with age; involu-
tion embracing about tvvo-liflhs of the depth of the whorl; umbilicus wide
and shallow, with walls not always abrupt; keel reduced, but distinct, gener-
ally consisting of an obtuse angle surmounted by a low, thin keel, not
serrated; surface ornamented with about forty-eight to iifty-two simple
flexuous ribs, usually arising in pairs from the small, rounded, umbilical
tubercules, and crossing the sides of the whorl obliquely forward. There
are also a few subordinate ribs that do not extend above the middle of the
sides. There is a single row of inconspicuous tubercules along the ventral
margin of the whorl that forms an angle between the flattened sides and
the beveled ventral surface. On the older shells these tubercules become
almost obsolete, as they are also upon young shells. Upon approaching
these tubercules the ribs bend more obliquely forward, and in tlie old shell
appear to cross the ventral surface, forming on the keel a faint crenulation.
On coils with a diameter of less than .8 cm. the ribs are not often seen, the
shell being almost smooth. The keel first makes its appearance, at a
diameter of.3cm.,as a faint line upon the ventral margin of the whorl.
The section of the whorl at this diameter is almost circular. The ribbing
begins with the development of the tubercules upon the outer margin,
which is followed by the extension of the ribs upward, and later, by the
appearance of the umbilical row of tubercules and a downward extension of
the ribs from them.

The largest example of this species collected has a diameter of 4.3 cm.,
though fragments of still larger coils were found which may belong to it.

S. oregonensis is related to S. propinqiia Stoliczka,
though easily separable from it.

A variety of S. oregonensis, of which a few small speci-
mens were collected, has considerably finer ribs, the

Geol— Vol. II,] A.WDERSOM— CRETACEOUS DEPOSITS. 1 23

number being about seventy-two, most of which belong
to the secondary class, not passing above the middle of
the sides.

Occurrence. — This species was found abundant at both
the Forty-nine Mine and at Smith's ranch, two miles to
the northwest, near Phoenix, Oregon. It belongs to a
horizon equivalent to the Lower Chico of the Sacramento
Valley.

The types are in the collections of the California
Academy of Sciences.

70. Schlcenbachia propinqua Stol.

Plate II, Figs. 34-38.

Ammonites propinqmis Stol., Pal. Ind., Vol. i, p. 53, PI. XXXI.

The species of Schlcenbachia which is believed to be
identical with the Indian form agrees so well in its meas-
urements and surface markings with Stoliczka's figures
and description, that were it found in the same region there
would be no hesitation as to its specific determination. In
sutural features, however, there seems to be a slight dif-
ference, though not sufficient to warrant a specific dis-
tinction. The suture represented in the figure is from a
younger whorl than that of Stoliczka's figure, having a
diameter of only 3.5 cm.

The shell is discoidal and flattened at a diameter of 2 or 3 cm., but becomes
thicker with increasing growth. At the diameter of 4 cm. the section of the
whorl is elliptical. The ribs of a single whorl number from forty to forty-
four, showing a tendency to bifurcate a little below the dorsal, or umbilical
margin. The keel, at first simple, becomes at a diameter of about 2 cm.
broken up in slight undulations.

This species is distinguished from 5". oregonensis not only by the smaller
number of ribs, but by a number of important and minor differences.
S. oreg07iensis lacks the prominent umbilical tubercules of the former; its
sides are also more flattened, the keel less conspicuous in older and in
young shells, and the abdominal area is more angular. Moreover, in
S. oregoncfisis this abdominal area is distinctly crossed by the ribs at the
diameter of a little over 3 cm., which does not appear to be the case either
in Stoliczka's figures or in the specimens from Southern Oregon. The
sutures show still more important differences, which only a comparison of
the types or the figures will make apparent.

124 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

In S. oregotiensis the ventral lobe has only slight subdivisions or none; the
lateral saddles are simple and rounded, the smaller divisions amounting to
only shallow scallops. The lateral lobe also shows a corresponding sim-
plicity of detail. This contrasts considerably with the more deeply cut lobes
and saddles of S. propinqua.

In S. propinqua the ventral lobe is divided by a siphonal indentation of
noticeable depth.

Both of these species appear to belong to Neumayer's
genus Schloeiibachiu, which probably includes the following
species.

71. Schloenbachia blanfordiana Stol. (?)
Plate I, Figs. 5-10.
Ammomies blanfordianus Stol., Pal. Ind., Vol. I, p. 46, PI. XXVI.

Among the collections made at the Forty-nine Mine, in
Southern Oregon, are several specimens of a shell plainly
of the type of Stoliczka's species, and at least very closely
related to it, if not identical.

The shell is fiat and discoidal, with moderately wide umbilicus surrounded
by about fourteen or more elevated tubercules; sides ornamented with about
forty ribs, which are clearly distinguishable on shells below a diameter of
3 cm., but becoming obsolete with age. The sides of the older whorls are
smooth, with the exception of the tubercules bordering the umbilicus and
the ventral margin. The ribs when they appear are flexuous, and show on
one specimen a tendency to form nodes considerably below the umbilical
row. The shell becomes a little more involute with age and finally clasps
about one-half of the preceding whorl. The keel is never prominent and
with increasing growth becomes, at a diameter of 3 cm., undulating and
apparently obtuse at 4.5 cm., or reduced to an obtuse ventral angle. The
suture, as far as it can be seen, agrees reasonably well with that of Sto-
liczka's figure, showing the same general character of lobes and saddles.

The ribs of the Oregon species seem to become lost at an earlier age than
in the Indian form, and the number of umbilical tubercules is not so great.
On the 3'oung shells the ribs first make their appearance at a diameter of
I cm., beginning at the ventral margin in small tubercules.

Occurrence. — This shell was found at the Forty-nine
Mine, near Phoenix, Oregon. It belongs to a horizon
equivalent to that of the Lower Chico beds of California.

Geol— Vol. II. ] ANDERSON— CRETACEOUS DEPOSITS. I 25

72. Mortoniceras crenulatum, sp. nov.
Plate I, Figs. 17-18.

Shell small, not above a diameter of 5 or 6 cm.; umbilicu.s wide and
shallow, with rounded and sloping shoulders; section of whorl quadrate, a
little higher than broad; surface ornamented by strong ribs, inclined forward
and nearly straight, with broad, round interspaces extending from within
the umbilicus to the keel; ribs bearing tubercules at the umbilical shoulder
and at the ventral shoulder, the latter extending laterally into thorn-like
spines. The keel is not apparently developed on the youngest whorls,
which are elliptical in section, but becomes visible at a diameter of about
4 or 5 mm. The keel, at first simple, becomes very soon finely crenulated,
but apparently not deeply serrate at a diameter of 5 cm. The ahell is
smooth up to a diameter of 2 or 3 mm. Septa not well shown.

This shell evidently belongs to Meek's genus Mortoni-
ceras, but is not closely related to any other found on the
Pacific Coast.

Occurrence. — Found in the lowest horizon of the Chico,
at Willow Creek, Siskiyou County, California. It was
associated with Trigonia Icana and other forms of the
Lower Chico below the horizon of Pachydiscus neza-
b err y anus.

73. Prionotropis branneri, sp. nov.
Plate I, Figs. 11-16.

cf. Prionocyclus woolgari Meek. Geol. Sur. Terr., Vol. IX, p. 455, PI. \'I1.

Among the species that should be regarded as "repre-
sentative" from the Interior Basin and the Pacific Border
none are more worthy of prominence than the above.

In form and ornamentation P. branneri strongly recalls Meek's species
from the Upper Missouri, but it is more inflated.

Shell more or less discoidal, but not compressed; greatest diameter of
largest specimen found 12 cm., though fragments of larger specimens were
collected; thickness at this diameter, 3.5 cm. Keel simple at first, appear-
ing at a diameter of 2 mm., showing faint undulations at i cm., and in old
age breaking up into a median row of nodes with rounded outline and with
rounded intervening depressions; umbilicus relatively wide, equal to about
three-eighths of entire diameter of coil, having abrupt walls, especially at the
diameter of 3 or 4 cm. Ribs twenty-five in number, simple at first, appearing
at a diameter of 2 mm. or earlier. At 5 cm. tubercules begin to develop upon

126 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser-

the external or ventral shoulder of the whorl in a double row; those of the
inner row have a greater lateral prominence, while the outer incline more
toward the plane of the keel. In shells of 3 or 4 cm. diameter these tuber-
cules have often a triangular appearance that is lost in older whorls. The
umbilical tubercules are more prominent upon alternate ribs, and are thin
and ridge-like in form. Above a diameter of 3 or 4 cm. the ribs become
depressed in their middle portion, forming only a bare connection of external
and umbilical tubercules in old age.

The suture line is simple; siphonal lobe long and relatively narrow, with
short, narrow teeth upon the side, parallel and equal; terminal teeth longer
and divided; first lateral saddle broad, bifid, and having either sharp or
rounded, small digitations; lateral lobe broad and tapering evenly in general
outline, indistinctly trifid, having sharp and narrow digitations; second lateral
saddle liigh and little cleft, scalloped at margin; second lobe and succeeding
saddle small and narrow. The digitations of the suture are not always
regular, different septa of the same specimen showing considerable varia-
tion. On the whole, however, they agree with the septa figured by Meek
for his species. Meek seems to have noticed in the Dakota types the same
irregularity. The furrows along the keel of the Oregon type are compara-
tively shallow, as seen upon the casts. Aside from this there is no other
difference in the two types, unless it be a little greater thickness for those
from Oregon.

Occurrence. — This species was found on the Smith
ranch, near Phcenix, Oregon, at whi(;h place several good
specimens were obtained, though from its abundance tiiere
it should be expected at the other localities. It belongs to
a horizon equivalent to that of the Lower Chico beds of
the Sacramento Valley.

The types are in the collections of the California
Academy of Sciences.

Geol.— Vol. II.] ANDERSON—CRETACEOUS DEPOSITS. I 27

LITERATURE CITED.

1893. Aquilera and Ordonez. Datos para la Geologia de Mexico.
1885. Becker, Geo. F. Notes on the Stratigraphy of CaHfornia. Bull.
U. S. Geol. Sur.^ No. 19, pp. 1-25. (In Vol. Ill, p. 197.)

1 888. Descriptive Geology of the Oathill, Great Western, and Great

Eastern Districts. — Geology of the Quicksilver Deposits of the
Pacific Slope. U. S. Geol. Sur., Monog. XIII, pp. 1-4S6.

1891. Notes on the Early Cretaceous of Cahfornia and Oregon.

Bull. Geol. Soc. Am., Vol. II, pp. 201-208.

1890. Bowers, Dr. Stephen. Orange County. TefUh Report State Min-
eralogist, Calif. State Mining Bureau, pp. 399-409.

1S95-96. Dall, W. H. Report on Coal and Lignite of Alaska. — Notes on
the Paleontology of Alaska. Seventeenth Ann. Rept. U. S. Geol.
Sur., Pt. I, pp. 865-872.

1889. Dawson, George M. On the Earlier Cretaceous Rocks of the

Northwestern Portion of the Dominion of Canada. Am. Journ.
Sci., 3rd Ser., Vol. XXXVIII, pp. 120-127.

1890. Notes on the Cretaceous of the British Columbia Region. — The

Nanaimo Group. A>n. Journ. Sci., 3rd .Ser., Vol. XXXIX, pp.
1S0-183.

1893. Diller, J. S. Cretaceous and Early Tertiary of Northern California

and Oregon. Bull. Geol. Soc. Am., Vol. IV, pp. 205-224.

1894. Diller, J. S., and Chas. Schuchert. Discovery of Devonian

Rocks in California. Am. Journ. Sci., 3rd Ser., Vol. XLVII, pp.

416-422.
1894. Diller, J. S., and T. W. Stanton. The Shasta-Chico Series.

Bull. Geol. Soc. Am., Vol. V. pp. 434-464.
1S92. Fairbanks, Harold W. The Pre-Cretaceous Age of the Meta-

morphic Rocks of the California Coast Ranges. Am. Geol., Vol.

IX, pp. 153-165.

1893. Notes on a Farther Study of the Pre-Cretaceous Rocks of the

California Coast Ranges. Am. Geol., Vol. XI, pp. 69-84.

1894. Geology of Northern Ventura, Santa Barbara, San Luis Obispo,

Monterey and San Benito Counties. Twelfth Rept. State Mineralo-
gist, Calif. State Mining Bureau, pp. 493-526.

1895- The Stratigraphy of the California Coast Ranges. Journ. Geol.,

Vol. Ill, pp. 415-433-
i8g6. Stratigraphy at Slate's Springs, with some Farther Notes on the

Relation of the Golden Gate Series to the Kno.wille. Am. Geol.,

Vol. XVIII, pp. 350-356.
J 898. Geology of a Portion of the Southern Coast Ranges. Jour 71.

Geol., Vol. VI, pp. 551-576.
1890. Felix, J., and H. Lenk. Beitrage zur Geologic und Palaeontologie

der Republik Mexico. Palcsontographica, Bd. XXXVII, pp.

180-189.
1898. Haug, Emile. Portlandien, Tithonique, et Volgien. Bull. Geol. Soc.

France, 3rd Ser., Vol. XXVI, pp. 197-228.

128 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

1893. Hill, Robert T. The Cretaceous Formations of Mexico and their

Relations to North American Geographic Development. Am.
Journ. Sci., 3rd Sen, Vol. XLV, pp. 307-324.

1894. HvATT, ALPHiiUS. Trias and Jura in the Western States. Bull.

Geol. Soc. Am., Vol. V, pp. 395-434.

1889. JOKOYAMA, M. Versteinerungen aus der Japanischen Kreide.

PalcEontographica, Vol. XXXVI, pp. 159-200.

1895. KossMAT, Franz. On the Importance of the Cretaceous Rocks of

Southern India in estimating the Geographical Conditions during

Later Cretaceous Times. Rec. Geol. Siir. India, Vol. XXVIII,

Part II, pp. 39-55.
1895^. Untersuchungen iiber die Siidindische Kreideformation. Bcitr.

Pal. iind Geol. Ocsterreich-Ungarns und des Ortcnls, Bd. IX,

Hefte 3 and 4.
1895. Lawson, a. C. a Contribution to the Geology of the Coast Ranges.

Amer. Geol., Vol. XV, pp. 342-356.
1897. Merriam, John C. The Geologic Relations of the Martinez Group

of California at the Typical Locality. Journ. Geol., Vol. V, pp.

767-775-

1901. A Contribution to the Geology of the John Day Basin. Bull.

Geol. Dcpt. Univ. Calif., Vol. II, pp. 269-314.

1890. NiKiTiN, S. Einiges iiber den Jura in Me.xico und Centralasien.

Neues Jahr.f. Min., 1890, Bd. II, pp. 272-275.

1894. Smith, Jas. P. Age of the Auriferous Slates of the Sierra Nevada.

Bull. Geol. Soc. Am., Vol. V, pp. 245-258.

1895. Mesozoic Changes in the Faunal Geography of California.

Journ. Geol., Vol. Ill, pp. 369-384.

1899. The Larval Stages of .Schlcenbachia. Journal Morphology,

Vol. XVI, No. I, pp. 237-268.
1901. The Larval Coil of Baculites. Amer. Naturalist, Vol. XXXV,

PP- 39-49-
1895. Stanton, T. VV. Contributions to the Cretaceous Paleontology of

the Pacific Coast. — The Fauna of the Knoxville Beds. Bull. U. S.

Geol. Sur., No. 133, pp. 1-132.
1895-96. The Faunal Relations of the Eocene and Upper Cretaceous

on the Pacific Coast. Seventeenth Ann. Rept. U. S. Geol. Sur.,

Pt. I, pp. 1011-1048.
1897. A Comparative Study of the Lower Cretaceous Formations and

Faunas of the United States. Jourti. Geol., Vol. V, pp. 579-624.
1S95. Steinmann, G. Beitrage zur Geologie und Palaeontologie von Sud-

amerika. N.Jahrb.f. Min., Beilage-Bd. X, pp. 1-118.
1865-73. Stoliczka, F. Cretaceous Fossils of India. Paleontologia In-

dica. Mem. Geol. Sur. India, Vols. I, III, IV.
1856. Trask, John B. Description of a New Species of Ammonite and

Baculite from the Tertiary Rocks of Chico Creek. Proc. Cat. Acad.

Sci., Vol. I (ist Ed., pp. 85-86, PI. II; 2nd Ed., p. 92, PI. II).

1891. Turner, H. W. The Geology of Mount Diablo, California. Bull.

Geol. Soc. Am., Vol. II, pp. 383-402.
1885. White, Chas. A. On the Mesozoic and Cenozoic Paleontology of
California. Bull. U. S. Geol. Sur., No. 15.

Geol.-Vol. II.] ANDERSON— CRETACEOUS DEPOSITS. 1 29

1885a. On New Cretaceous Fossils from California. Btill. U. S. Geol.

Sur., No. 22, pp 1-14. (In Vol. Ill, p. 349.)
1889. On Invertebrate Fossils from the Pacific Coast. (Invertebrate

Fossils from California, Oregon, Washington, and Alaska.) Bull.

U. S. Geol. Sur., No. 51, pp. 1-102. (In Vol. VIII, 18S9, pp.

441-532.)
1891. Correlation Papers. — Cretaceous. Btill. U. S. Geol. Sur.,

No. 82.
18SS. Remarks on the Genus Aucella, etc, (in Becker's Monograph

XIII, U.S. Geol. Survey).
1876-84. Whiteaves, J. F. Geol. Sur. Canada. Mesozoic Fossils. Vol. i
Part I, 1876: On Some Invertebrates from the Coal-Bearing

Rocks of the Queen Charlotte Islands, collected by Mr. James Rich-
ardson in 1S72.

Part II, 1879: On the Fossils of the Cretaceous Rocks of Van-
couver and Adjacent Islands in the Strait of Georgia.

Part III, 1884: On the Fossils of the Coal-Bearing Deposits of

the Queen Charlotte Islands, collected by Dr. G. M. Dawson in

187S.
1893. The Cretaceous System in Canada. Trans. Roy. Soc. Canada,

Vol. XI, Sec. 4, pp. 1-19.
1900. Willis, Bailey. Some Coast Migrations, Santa Lucia Range,

California. Bull. Geol. Soc. Amer., Vol. XI, pp. 417-432.

INDEX OF SPECIES
CRETACEOUS DEPOSITS OF THE PACIFIC COAST.

New species in heavy face, synonyms in italics.

ACANTHOCERAS 39, 40, 58, 60

cotnpressum 107

iiianiillare 42. 108

naviculare 60

rhotoniagense 58, 107

spiniferum 109

ActEEon 42

Actreonella oviformis 93

Actpeonina pupoides 75

Ammonites . . 99

batesi 84, 85, 87

hlanfordianus 124

cnln 84

chicoensis 116, 117

dispar 106

duvalianus 81

fraternus 102, 103

incertus 101

jugalis 80, 99

kayci 83

lalidorsatus lOO

viantelli 108

ncivberryanus 102

proftinqUHS 123

rliotomagensis var. conipressus . 107

rouyanus 80

sacya 82

stoliczkanus 108

S7iciae>isis 103, 104

sugata 98

whitneyi 82, 83

Auchura 42

californica 93

condouiana 76

Ancyloceras percostatum 41

reniondi 63

Archomya undulata 42

Astarte trapezoidalis 45

Atresias liratus 45

Aucella crassicollis 46

mosquensis 45

Piochi 46, 51, 52, 66

Avicula 42

Baculites chicoensis . . 36, 50, 58, 60, 92

fairbauksi 60, 74, 92

vagina 60, 92

Barroisiceras 119

Belemnites 40, 45, 46, 63, 66

impressus 42, 43

Cardinia 45

Cerithium 44

Chione varians 35, 93

CinuHa obliqua 34, 50

Coralliochama orcutti 38, 75

Crioceras latum 42, 43

percostatum 42, 45

CucullEca sp 35

Cucullsea truncata 35, 76

Cylichna 33

Desmoceras . . .40, 44, 58, 63, 73, 80, 93

sp 40

ashlandicum 61,76,100

beudanti 42, 63

breweri 53

colusaense ... 96

darwini 51

dilleri 97

hoffnianni . . . .40,71,93.94,96, 97

j'lgalis 71, 99, 100

latidorsatiis 53

lecontei 95

mayorianum 93

plauulatum 63, 93, 96

subquadratum 95

sugatuni 39, 89, 98

voyi 63, 100

Diptychoceras Iseve 42

Douvilliceras maniillare 108

Rrato veraghoijrensis 75

I'lxogyra parasitica 35

Gabbioceras batesi 87

Goniomya borealis 39

Gyrodcs expansa 34

siskiyouensis 75

Hamotis antiqua 75

ir'S ■ ;. 75

lomaensis 75

Hamites 39,58, 60, 61

a;quicostatum 90

artnatutti 40, 89

cylindraceus 61, 88, 89

ellipticus 87

royerianus 88

phoenixeusis 88

solanoense 90

ilaploceras cumshewaense lOl

Helicancylus oequicostatus . . . . 90, 92

Ilelicaulax 42

bicarinata 42

Helicoceras 39, 60

indicum 91

reussianum 60

Ileteroceras 39

ceratopse 91

reussianum 91

Holcodiscus theoboldianus .... 63, 101

Homomya concentrica 35

Hoplites 40, 44, 46

Hypsipleura 44

INOCERAMUS 38, 39, 46, 59

adutica 73

crippsi 58

klataatheusis 73

[130]

Geol.— Vol. II.] ANDERSON— CRETACEOUS DEPOSITS.

131

Inoceramus labiatus 57,58,59,60

luytiloides 59

whitneyi 35, 58

Lima 42

Liiidigia nodosum 90, 92

Liocium punctatum 42

I.ucina colusaensis 45

Lytoceras 39, 40, 42, 44, 58, 63, 73

angulatutn 87

argonautarum 41, 85

batesi . . . 43, 63, 71, 83, 84, 85, 86, 97

cala 63, 84

duvalianuni 81, 82

jacksonense 82

iukesi 58

kayei 61, 83

sacya 42, 63. 82

timotheanum 63

varuna 61

Mactra ashburueri 74

gabbiana 74

Meekia sella 35

Mitliea grandicosta 42

Modiola major 45

Mortoniceras crenulatum 125

Myoconcha 45

Nautilus 40, 77, 78

campbelli 77

charlottensis 78

gabbi 77, 78

kayeanus 77

pseudo-elegans 77, 78

suciatinsis 63, 78

texanus 77

Nerinea 42

Nucula truncata 35

OSTREA 38

Olcostephanus 40, 44, 46, 66

traski 42

Oxytoma mucronata .42

Pachvdiscus 40, 58, 60

henleyensis 89, 104

merriami 103

newberryanus ... 40, 50, 58, 102, 125

sacramenticus 105

suciaensis 50, 58

Pecten 38

californicus 75

complexicosta 45

operculiformis 40

Pectuiiculus pacificus 74

subplanatus 74

veatchi 35, 36

Pentacriiius 36

Perisphinctes 44. 66

Pholadomya anaana 73, 93

Phylloceras 40,42,44, 80

onoense 63, 86

ramosum 58,61,86, 99

shastalense 80

velledse 63

Placenticeras 40, 59

californicum 50, 78, 90, 98

Placenticeras pacificum . -50,79,90, 98

Pleuromya 42

Pleuropachydiscus 94

Plicatula varia 42

Potamides diadema 42

Prionocyclus branneri 59

woolgari 59, 125

wyomingensis ... 59

Prionotropis branneri 125

crenulatum 40

Protocardium scitulum 39

Ptychoccras iFqukostatum 90

Puzosia darvvini loi

RINGINELLA 42

Rhynchonella densleonis 72

gnathophora 72

maudensis 72

whiteana 72

whitneyi 45

SCAPHITES 39, 59, 73, 76, 109

tequalis no

condoni 40, 111

var. appressus 112

gilHsi 39, 59, 110

inermis 113,115

klatnathensis 39, 59, 115

larv;eformis 59, 115

perrini 114

roguensis 112

warren i 59, 110

Schlcenbachia . . . .39,59,60,73,76,116

bakeri 121

blanfordiana 124

buttensis 116, II8

chicoensis 58, 116

gabbi 74,116,117,118,119

inflata 42, 63, 116

knighteni 119

multicosta 120

oregonensis . . 39, 121, 122, 123, 125

propinqua 63, 122, 123

siskiyouensis 119

varians 118

Schliiteria 99

diabloensis 80

Schizaster lecontei 99

Solarium wallalaense 38

Sonneratia stantoni 105

Stoliczkaia dispar 63, 106

Tetragonites 84

Thetis elongata 42

Trigonarca 35

Trigonia 37

Eequicostata 40

dawsoni 35

evansana 35, 35, 58

leana 40, 125

tryoniaua 58

Turbo colusaensis 45

raorganensis 45

wilburensis 45

Turnlites 92

Turritella 35, 38

132 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

EXPLANATION OF PLATE L

Page.
Schloenbachia knighteni, sp. nov. 119

Fig. I. Adult specimen.

Figs. 2-3. Young shells.

Fig. 4. Enlarged suture of young shell.
Schloenbachia blanfordiana ? Stol. 124

Figs. 5-6. Adult shells.

Figs. 7-9- Young shells.

Fig. 10. Very young shell; X2.
Prionotropis branneri, sp. nov. 125

Figs. 11-12. Adult shells.

Figs. 13, 14, 15, 16. Young shells.
Mortoniccras ctrniilatum, sp. nov. 125

Figs. 17-18. Ventral and side views of adult shell with spines.
Schloenbachia siskiyouensis, sp. nov. 119

Figs. 19-20. Side and front views of adult shells; natural size.
Schloenbachia chicoensis Trask. 116

Figs. 21-22. Side and front views of young shells.

PhdcCalAcad SclS'^ 5eh Bedl.VdlII.

[Andersdn] Rate I.

a y

134 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

EXPLANATION OF PLATE IL

Page.

Schloetibachia chico'ensis Trask. 116

Figs. 23-24. Mature shells.

Fig. 25. Suture line of same.

Schlceiibachia bakeri, sp. nov. 121

Figs. 26-30. Mature shells.

Fig. 31. Enlarged view of ventral surface.

Fig. 32. Young shell.

Fig. 33. Enlarged suture of young shell.

Schlcenbachia propinqua Stol. 123

Figs. 34-35. Mature shells.

Fig. 36. Suture line of same.

Figs. 37-38. Young shells.
Schlcenbachia knighteni, sp. nov. 119

Figs. 39-40. Young shells.
Schlcenbachia multicosta, sp. nov. 120

Figs. 41-43. Young shells.

Fig. 44. Very young stage.

Fig. 45. Very young shell; X2.

Figs. 46-47. Mature shells.
Schlcenbachia oregojiensis, sp. nov. 122

Figs. 48-49. Adult shells.

Figs. 50-54. Young shells.

Figs. 55-56. Very young shells; X2.

Fig- 57- Suture of young shell.

Scaphites condotii, sp. nov. 11 r

Figs. 58-59. Mature shells.

Figs. 60-62. Young shells.

Fig. 63. Suture line.

Scaphites condoni var. appressus, var. nov. 112

Figs. 64-65. Mature shells.

Fig. 66. Young of same.

Scaphites roguensis, sp. nov. 112

Fig. 67. Mature shell.

Figs. 68-70. Young shells of same.
Scaphites perrini, sp. nov. 114

Figs. 71-72. Mature shells; X2.

Fig. 73. Suture of same.

Phdc.CalAcaD-Sci.3^ 5EH GEOL VULll

[ANUERSQniPivoi: II

^'W

ilr^/^

riirrr^

4rir<

Kfjiriifsujiu.vffxt.

136 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

EXPLANATION OF PLATE IIL

Page.
Scaphites inermis, sp. nov. 113

Fig. 74. Mature shell.

Figs. 75-77. Young shells.
Scaphites klaniathensis, sp. nov. 115

Figs. 78-79. Mature shells.

Figs. 80-81. Young of same.
Hoplites parva, sp. nov.

Figs. 82-83. Natural size.

Fig. 84. Suture of same.

Scaphites gillisi, sp. nov. no

Fig. 85. Mature shell.

Figs. 86-87. Young coils.

Fig. 88. Suture line.

Desmoceras voyi, sp. nov. 100

Figs. 89-90. Shell natural size.
Sonneratia statitoni, sp. nov. 105

Figs. 91-93. Mature and young shells.
Desmoceras lecontei, sp. nov. 95

Figs. 94-95. Adult, but not full grown shell.
Helicoceras indicitin ? Stol. 9^

Figs. 96-97. Coiled portion; X4.
Desmoceras sugatum Forbes. 98

Figs. 98-99. Mature shells.
Heteroceras ceratopse, sp. nov. 91

Fig. 100. Portion of coil; natural size.

Fig. loi. Section of same.
HcH>nites ellipticits, sp. nov. 87

Fig. 102. Side view; natural size.

Fig. 103. Section of whorl.
Hamites phcenixetisis, sp. nov. 88

Fig. 104. Body chamber; natural size.
Schl'uteria diabloensis, sp. nov. 80

Figs. 105-106. Shell natural size.

Hac.CALAcAn.Sci.3" 5er BeolVdlIL

[Ai^idehsdn] Plate 111

"-^s^

f''"^^

^" 9^A -^

■■>■■

:^^

f--^^.

lOfl

lilH BBirmK K HTT. ST.

.VAWWSBtj>M«r^

138 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

EXPLANATION OF PLATE IV.

Page.

Desmoceras ashlandicum, sp. nov. 100

Figs. 107-109. Young adult shells.
Schloenbachia buitcnsis, sp. nov. 118

Fig. no. Full grown shell.

Fig. III. Section of whorl.

Phylloceras shastalense, sp. nov. 80

Figs. 1 1 2-1 13. Mature shells.

Figs. 114-115. Younger shells.
Desmoceras dilleri, sp. nov. 97

Figs. 116-117. Mature shells.
Desmoceras subquadratuin, sp. nov. 96

Figs. 118-119. Young adult shells.

Prdc.CalAcad Sci.3? 5ER.GEaL.VaLn.

[Anderson] Fute IV

'"V;

V _ 100 ^-

-*T tt "m

W i ^\'f

■mt iwnnm * wrf. (U;

140 CALIFORNIA ACADEMY OF SCIENCES. [Proc. ',d Sek.

EXPLANATION OF PLATE V.

Page.
Desmoceras hoffmanni Gabb, 97

Figs. 120-121. Young adult shells.

Figs. 122-123. Younger shells.
Lytoceras ( Tctraffonites) jacksoncnse, sp. nov 82

Figs. 124-125. Adult shells, without body-chamber.
Holcodiscus, cf. H. theobaldiatitis Stol. ioi

Figs. 126-127. Young adult shells; natural size.
Desmoceras colusaense, sp. nov. 96

Figs. 12S-129. Adult shell; one-half natural size.
Hamites arinalmn, sp. nov. 89

Fig. 130. Side view, body-whorl .

Fig. 131. Ventral surface, showing spines.

Fig. 132. Cross-section of same.

Fi=uc.CALAEAD Bci.S? 5eh Beql.VdlIL

[Andersqm] Rate V

130

142 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

EXPLANATION OF PLATE VL

Page.
Pachydiscus sacramenticus, sp. nov. 105

Fig- 133- Full grown shell.

Fig. 134. Young shell.
Pachydiscus merriauii, sp. nov. 103

Figs. 135-136. Full grown shells.

Figs. 137-138. Younger coils.
Lytoceras (Gabbioceras) aiigulatiini (Gaisb's var.), sp. nov. 87

Fig- 139- Partial restoration of an adult shell.
Lytoceras rel. duvalianum d'Orb. 81

Figs. 140-143. Partly grown shells.
Schlcenbachia oregonefisis, sp. nov. 122

Fig. 144. Cross-section of whorls; 22.25 mm. diameter.
After J. P. Smith.

FRDC CALAnAE. Bci 3^ 5eh Geol VdlII.

^Andekuun] PlkteVI

141

<rti^sjj€*;:vF^

144 CALIFORNIA ACADEMY OF SCIENCES. [Proc. .^d Ser.

EXPLANATION OF PLATE VH.

Page.
Lytoceras iimotheaniun IMayor. 63

Figs. 145-148. Young adult shells.
Schlcenbachia oregoncnsts, sp. nov. 122

Fig. 149. Very young shell; diameter 5.6 mm.

Fig. 150. Very young shell; diameter 1.65 mm.
After J. P. Smith.
( For cross-section see Fig. 144, Plate VI.)
Pholadomya anadna, sp. nov. 73

Fig. 151. Shell; natural size.
Baculiles fairbanksi, sp. nov. 92

Fig. 152. Adult; natural size.

Fig. 153. Cross-section of same.
Lytoceras argonautaruin, sp. nov. 85

Figs. 154-155. Young shells; two-thirds natural size.
Mactra gabbiana, sp. nov. 74

Fig. 156. Shell; natural size.
Rhynchonella densleonis, sp. nov. 72

Figs. 157-158. Top and front views.
Pedunculus pacificus, sp. nov. 74

Fig- 159- Shell; natural size.
Rhyfichonclla whifeana, sp. nov. 72

Figs. 160-161. Top and front views; natural size.

v\LAn bCI.J" ^t:

r-o

146 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 30 Ser.

EXPLANATION OF PLATE VIIL

Page.
Placenticeras pacificum Smith. 79

(After J. P. Smith, Proc. Cal. Acad. Sci., 3d Ser., Geol.,
Vol. I, Plate XXV.)
Figs. 162-163. Four coils; diameter 20.5 mm.; X2.7. Ar-
royo del Vall(5, Alameda County, California.
Fig. 164. Four and five-sixths coils; diameter 47 mm.;

natural size. Henley, California.
Pachydiscus hetileyetisis, sp. nov. 104

Fig. 165. Section of whorl reduced, at fourteen inches.
Fig. 166. Section of whorl at a diameter of three and one-half
inches.
Gyrodes siskiyouensis, sp. nov. 76

Fig. 167. Front view; natural size.
Fig. 168. Top view of same.
Belemnites, sp. Texas Flat, Shasta County, California. 40

Fig. 169. Shell partly restored; natural size.
Fig. 170. Enlarged view, showing protoconch.
Placenticeras pacificum Smith. 79

Figs. 171-172. Adolescent stage; two and five-sixteenths coil;
diameter 2.32 mm. ; Xio. Henley, California.
Placejiticeras cali/ortiicum, sp. nov. 78

(After J. P. Smith, Proc. Cal. Acad. Sci., 3d Ser. Geol.,
Vol. I, Plate XXV.)
Fig. 173. Three coils; diameter 8 mm.; X2.7. Henley,

California.
Figs. 174-175. Adolescent stage; three and five-eighths coils;
diameter 14 mm. ; X2. Henley, California.
Figs. 176-177. Adolescent stage; four coils; diameter 22 mm.;
X2. Arroyo del Vall6, Alameda County,
California.
Fig. 178. Four and one-half coils; diameter 34.5 mm.;

X2. Henley, California.
Anchura cotidojiiana , sp. nov. 76

Fig- 179- Full grown shell; natural size.

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148 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

EXPLANATION OF PLATE IX.

Page.
Placenticeras pacificnm Smith. 79

(After J. P. Smith, Proc. Cal. Acad. Sci., 3d Ser., Geol.,
Vol. I, Plate XXVI; figure redrawn.)
Fig. 180. Adult shell, diameter 172 mm., six and one-sixth
coils; natural size. Henley, California.
Erato veraghoorensis (?) Stol. 75

Figs. i8r-i82. Shell, natural size.
Haliods lomacttsis, sp. nov. 75

Fig. 183. Shell; natural size.
Hamites ( Ptyclioceras) sola7to'ensc, sp. nov. 90

Fig. 184. Rear view of body-chamber; natural size.
Inoceramus klamaihensis, sp. nov. 73

Fig. 185. View of left valve.
Fig. 186. Left valve with hinge; natural size.
Acanthoceras compresstim, sp. nov. 107

Fig. 187. Shell; natural size.
Inoceravms adimca, sp. nov. 73

Figs. 188-189. Front and rear views of adult shell.

■ K UtUL V2_U.

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150 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

Fig.

190.

Fig.

191.

Fig.

192.

Fig.

193-

Fig.

194.

Fig.

195-

Fig.

196.

Fig.

197.

Fig.

198.

Fig.

199.

Fig.

200.

Fig.

201.

Fig.

202.

Fig.

203.

EXPLANATION OF PLATE X.

Suture lines of new species.

Page.

Desmoceras lecontei. 95

Hamiles cUipticus. ^7

Desmoceras dilleri. 97

Desmoceras subquadratum. 96

Bacidites fairbanksi. 92

Pachydiscus sacramcnticus. 105

Desmoceras ashlatidiciim. 100

Holcodiscus, cf. H. theobaldia^ius. loi

Sonneratia stantoni. 105

SchliUeria diablocnsis. 80

Desmoceras colusacnse. 96

Hcteroceras ceratopse. 9'

Prionotropis bramieri. 125

Desmoceras hoffmanni. 94

FHDC CalAcad Sci 3^ SehGedlVdlII
,1

IAnhehsdm] Piate X.

UTK IWirmBt K BXY. ST

152 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser.

EXPLANATION OF PLATE XL

Page.
Schlosnbachia oregonensis, sp. nov. 122

After J. P. Smith, Journ. Morph. Vol. XVL 1899, Plates A and B.

Figs. 204-206. Protoconch, phylembryonic to ananepionic. Y-

Figs. 207-208. Phylembryonic to paranepionic; diameter 0.58 mm.;
one-half whorl, first eight septa, glyphioceran stage
at the sixth. V.

Fig. 209. Paranepionic, glyphioceran substage; diameter 0.64

mm.; third to tenth septa, five -eighths of a
whorl. Y-

Figs. 210-211. Phylembryonic to paranepionic, glyphioceran sub-
stage; diameter 0.68 mm.; three-quarters of a
whorl, nine septa, 'j .

Figs. 212-213. Paranepionic, paralegoceran substage; diameter 2.25
mm.; two and three-eighths whorls, --f.

Figs. 214-215. Ananeanic, Parastyrites stage; diameter 3.70 mm.;
three and one-fourth whorls, j'.

Fig. 216. Paranepionic, glyphioceran substage; diameter 0.74

mm.; seven-eighths of a whorl. \".

Figs. 217-218. Paranepionic, transition from glyphioceran to gastrio-
ceran substages; diameter 1.20 mm.; one and
three-eighths whorls, y.

Figs. 219-220. Paranepionic, transition from glyphioceran to gastrio-
ceran substage; diameter 1.33 mm.; one and five-
eighths whorls. Y-
Paranepionic, gastrioceran substage; diameter T.65

mm.; one and seven-eighths whorls. Y-
Ananeanic, Styrites stage; diameter 3. 10 mm. ; two and

seven-eighths whorls. Y^-
Metaneanic, advanced adolescent stage; diameter
5.60 mm.; three and three-quarters whorls, show-
beginning of ribs at a diameter of 4.70 mm. Y-

Figs.

221-

-222

Figs.

223-

-224.

Fig. :

225.

Fedc.QalAcad, Bci.3^ See, Gedl VdlII.

154 CALIFORNIA ACADEMY OF SCIENCES. [Proc. ^d Ser.

EXPLANATION OF PLATE XIL

The Development of B acuities chicoensis Trask.'

Upper cretaceous, Chico beds, Jordan ranch, Arroyo del
Vall6, eight miles southeast of Livermore, Alameda County,
California.

Fig. 226. Protoconch, front view, diameter 0.48 mm. ; enlarged

15 times.
First septum, showing siphonal caecum.
Second septum, at diameter 0.58 mm.
Larval shell, at one-fourth of a revolution, diameter

0.58 mm.; 15 times enlarged.
Sixth septum, at one-half revolution.
Larval shell, showing the embryonic constriction, and

the first larval body-chamber; 15 times enlarged.
Larval shell at three-quarters of a revolution, diameter

0.83 mm.; enlarged 15 times.
Larval shell, showing the ornamentation of the embry-
onic and early larval stage, and the ananepionic

body-chamber; enlarged 15 times.
Shell at end of the second larval stage, diameter 1.6

mm.; 15 times enlarged.
Larval shell, showing the periodic swelling of the

siphuncle. Diameter i.oomm.; enlarged 15 times.
Figs. 239-240. Early adolescent stage, showing the unsynimetric

shape of the larval coil, and the contraction of the

shell at the beginning of this stage; enlarged 15

times.
Fig. 241. Composite drawing from several specimens, showing

the development of the septa from the embryonic

into the adolescent stage; enlarged 5 times.

' These drawings are copied from a paper by J. P. Smith, "The Larval Coil of
Baculites," American Naturalist , Vol. XXXV, p. 39, Jan., 1901. The numbers on this
plate do not correspond to the originals of Smith's plates, since not all his figures are
reproduced here.

Fig.

227.

Fig.

228.

Fig.

229.

Fig-

230.

Figs.

231-232.

Figs.

233-234-

Fig.

235-

Figs.

236-237.

Fig.

238.

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238

232

233

226

231

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PROCEEDINGS OF THE ACADEMY.

(Octavo.)
Third Series.

GEOLOGY.
Vol. I.

No. I— The Geology of Santa Catalina Island. By William Sidney

Tangier Smith j .50

No. 2— The Submerged Valleys of the Coast of California, U. S. A. ,

and of Lower California, Mexico. By George Davidson . . .50
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Glyphioceratidse. By James Perrin Smith 35

No. 4— The Development of Lytoceras and Phylloceras. By James

Perrin Smith 35

No. 5— The Tertiary Sea-Urchins of Middle California. By John ^

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No. 6— The Fauna of the Sooke Beds of Vancouver Island. By ( ^

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No. 7— The Development and Phylogeny of Placenticeras. By James

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Anderson 5i • 75

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F>ROCKEDI]MQS

OF THK

CALIFORNIA ACADEMY OB^ SCIENCES

Third Series

Geology Vol. II, No. 2

A Stratigraphic Study

in the

Mount Diablo Range of California

Frank M. Anderson

Curator of the Department of Invertebrate Paleontology

» With Twenty-three Plates

Issued December 4, igo^

SAN FRANCISCO

Published by the Academy

1905

COMMITTEE ON PUBLICATION

Leverett Mills Loomis, Chairman
Alphkus Bull Joseph W. Hobson

THE HICKS-JUDn PRESS
SAN FRANCISCO

]PROCKEDINGS

OF THB

CALIFORNIA ACADEMY OF SCIENCES

Third Series
Geology Vol. II, No. 2

Issued December 4, igo^

A STRATIGRAPHIC STUDY IN THE MOUNT DIABLO
RANGE OF CALIFORNIA

BY FRANK M. ANDERSON
Curator of the Department of Invertebrate Paleontology

CONTENTS

Plates'XIII-XXXV p^^^

Preface 156

Introduction 157

Divisions of the Mount Diablo Range 158

Stratigraphic Series 159

Franciscan and Associated Rocks 159

Cretaceous Strata 160

Eocene Formations 162

Miocene Formations 168

Later Neocene Beds 173

Coalinga Beds 174

Etch egom Beds 178

Etchegoin Sands 178

San foaquin Clays 181

Tulare Formation 181

Stratigraphic Relations 182

Other Occurrences of Lower Miocene within the Interior

Basin 186

San Emidio Section 186

Beds of the Carisa Ranch 186

Kern River Beds 187

Correlations 188

Conclusions 190

Descriptions of Species 191

[i] November 2S, 1905

156 CALIFORNIA ACADEMY OF SCIENCES [Proc. 3D Ser.

Preface.

The systematic study of the field covered by this paper,
and its stratigraphy, was begun for purely economic and
private purposes and not for publication; nevertheless, so
much data and material of a scientific interest have been
gathered, and so much information has been acquired, part
of which, though of a practical nature, it is permissible to
make public, that some of the more general facts are here
offered as a contribution to the geological literature of Cali-
fornia.

The matter and conclusions set forth are the result of a
field-study extending over a period of more than two years,
made partly alone, and partly with the cooperation and aid
of Mr. Josiah Owen, whose knowledge of the field is both
extensive and practical to a high degree, and to whom are
due many of the stratigraphic observations here presented.

The advantages for a statigraphic and faunal study offered
by this field are in most respects unsurpassed anywhere.
The aridity of the climate, and the soft and crumbling
nature of the younger sediments, together with the action of
the wind, combine to give excellent and accessible exposures
of rock, while in many cases the almost perfect preservation
of the shells and other fossils renders the task of identifica-
tion satisfactory. The structure of the rocks, moreover, is
generally simple, and strata are readily followed to almost
any extent, particularly along the eastern flanks of the range,
to which most of the field-work was naturally confined.

In this connection it is proper to mention the generous
interest taken in this work by Professor E. T. Dumble and
the many facilities afforded through his kind cooperation.

The fossils collected during the field explorations, aggre-
gating several thousand in number, were donated to, and
have become the property of the California Academy of
Sciences.

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY 157

Introduction.

In order that one of the main purposes of this paper may
be understood, it is necessary, at the outset, to make the
following statement. It is believed that during the Neocene
periods, if not throughout the Tertiary, there were a number
of more or less separated basins, or minor faunal provinces,
along the Pacific border, two of which are represented
within the confines of California.

The California interior basin was bounded approximately
by the outer Coast Range, the Tehachapi Range, and the
Sierra Nevada. At the south the barrier described a broad
curve, following the axis of the Santa Cruz and Santa Lucia
ranges along the present coast, thence turning eastward to
Pine Mountain and the Tehachapi Range, which united it to
the Sierra Nevada. The interior basin thus occupied the
region of the Great Valley of California and the inter-
montane valleys between that and the coast.

The basin thus bounded and outlined is clearly distin-
guished from that of the open ocean of the time, the littoral
deposits of which form a narrow fringe at intervals along the
present coast, or fill the narrow coastal valleys, especially
at the south.

The present paper is concerned especially with the deposits
of the interior basin of California, which are believed to be
typically represented in the Mount Diablo Range and in a
few other localities within the Great Valley.

The Mount Diablo Range, as defined by Whitney,'
extends along the southwestern border of the Great Valley
of California, from Mount Diablo, near the Straits of Car-
quinez, southeasterly to Pine Mountain, where it unites with
the Tehachapi Range, which links it with the Sierras. Thus
the valley of the San Joaquin is surrounded by a continuous
barrier of ranges on the east, south, and west, while it is
separated by the Mount Diablo Range from the rest of the
interior basin occupied by the Salinas and the Carisa valleys.
In other words the Mount Diablo Range divides the basin of

1 Geo!. Surv. Calif. Geol. v. i, pp. 8-60.

158 CALIFORNIA ACADEMY OF SCIENCES [Proc. 3D Ser.

the California interior somewhat centrally, presenting at the
same time magnificent stratigraphic sections that are unsur-
passed anywhere in the West in their exposures.

Divisions of the Mount Diablo Range.

Whitney divided the Mount Diablo Range into six more or
less distinct sections separated by certain low passes, some
of which at least are notable breaks in the range, and
though the region was not so well known then as now, it is
still useful to observe some of these divisions.

The San Carlos Division of Whitney embraced that
portion of the range between the Panoche Pass on the
north and the Estrella (or Cottonwood) Pass on the south,
thus including most of the western border of Kings and
Fresno counties, or the territory adjacent to the Devil's Den,
Coalinga, and "Oil City" petroleum districts. It is this
division of the range which is chiefly the subject of the
present paper, the various features of which will serve to
illustrate the facts and conditions prevailing throughout the
range.

Rocks of various kinds are found among the formations of
this section ranging in age from Paleozoic to Recent, and
embracing both sedimentary and igneous elements, though
the latter are of only minor importance. For the most part
the formations are arranged in roughly concentric fashion
about the two principal centers of this division, one of which
lies to the south and the other to the northwest of the
Coalinga district. On the eastern slope of the range the
structure is usually monoclinal, the strata dipping at varying
angles toward the Great Valley, generally toward the east or
north. The Cretaceous and early Tertiary beds stand at a
high angle, while the younger strata often have a much
ijentler inclination.

The general topographic features of the Mount Carlos
Division of the range are similar to those of other portions,
and vary according to the underlying formations. The con-
centric arrangement of the rocks above referred to gives rise
to similarlv concentric series of hills and dales that have

Geol.— Vol. II.] ANDERSONSTRATIGRAPHIC STUDY 1 59

developed in accordance with the character and hardness of
the rocks affected. The higher portions of the range are
rocky and i-ugged, while the lower eastern slopes are often
formed of gently undulating hills extending in parallel ranks
and gradually sinking below the plain to the eastward.

The principal streams of this section, flowing toward the
Great Valley, are the Panoche, San Carlos, Cantua, Los
Gatos, and Alcalde creeks, each of which cuts deep can-
yons into the softer formations near the valley, but heads
high up on the rocky ridges in the central parts of the
range. Farther south are the Sunflower and Antelope
valleys with converging streams.

Stratigraphic Series.
Franciscan and Associated Rocks.

The oldest rocks met with in the San Carlos Division of
the range are those generally referred to the Franciscan
series, including not only the well known sedimentary fac-
tors, but also certain basaltic and other igneous rocks closely
connected or involved with them. It is perhaps sufficient to
say that the entire series, including the eruptives, are in point of
age pre-Cretaceous, though they have been variously assigned
by different authors, wholly or in part, to the Paleozoic,
Jurassic, or Cretaceous periods.

The sedimentary members of the Franciscan series repre-
sented in this field include the rocks ordinarily found asso-
ciated in this formation, such as radiolarian jaspers, sand-
stones, slates, and schists, and perhaps certain conglomerates.

Closely connected with the Franciscan rocks territorially
are the serpentines of the range. While it is not likely that
the connection is anything more than territorial, as in point
of age the serpentines are of more recent origin and there-
fore more closely connected with the succeeding series, still,
as their association with the Franciscan rocks is habitual
even outside this district, they may be better classed with
these than with any other formations.

l6o CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

The geologic and topographic features of the series are
the same as everywhere in the coast ranges both north and
south of the Bay of San Francisco. In this field the series
is confined in its occurrence to the axis of the chief range
extending west of the Coalinga district, or, more accurately,
to a few prominent areas within that range.

There are two or three principal areas of Franciscan and
serpentine rocks, separated to a considerable extent by an
area of Cretaceous strata. One of these lies to the south of
the upper tributaries of Alcalde Creek (or Warthan Canyon),
and extends from there southeasterly to Cottonwood Pass ;
another extends from the upper branches of Los Gatos Creek
northward toward the Panoche Valley and the tributaries of
the San Benito River, and therefore includes the New Idria
quicksilver district and the San Carlos and San Benito peaks.

The most extensive formation in this area is undoubtedly
serpentine. To the south and west of New Idria, serpentine
is almost the only rock to be seen for many miles. The
sedimentar}' rocks of the Franciscan series are mostly con-
fined to the southern and western borders of the area.

Cretaceous Strata.

Lying along the eastern margins of the Franciscan areas
and filling wide spaces between, are Cretaceous rocks, form-
ing a stratified series of great thickness and dipping steeply
toward the Great Valley. An important area of Cretaceous
rocks is that between the Alcalde and Los Gatos creeks near
Coalinga.

The Cretaceous strata include both the Knoxville and
Chico divisions, with the intervening Horsetown Beds appar-
ently omitted. The usual nonconformity between these mem-
bers has not been proved in this field directly, though there
are abundant grounds for believing that it exists.

The Knoxville consists of a thick series of dark clay shales
and thin-bedded sandstones, lying next to the Franciscan
rocks. They have been particularly noted along the head
waters of Alcalde Creek, near the Fresno Hot Springs, on

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY l6l

the head of the Jacalitos Creek, and at the Devil's Den,
south of the Sunflower Valley. The Cretaceous rocks in
the vicinity of the New Idria quicksilver mines have long
been known. From there they extend southeasterly to Coa-
linga. In the Knoxville portion the only fossils so far dis-
covered are species of A7ninonites, (^Hoplites), Beleniuites, and
imperfect plant remains.

The Chico rocks, which are chiefly in evidence north of
Alcalde Creek, and still more so north of Los Gatos Creek,
form a thick series of yellow clay shales and tawny colored
sandstones. To the north of Los Gatos Creek they extend
high up on the range and constitute the most conspicuous
formation of the mountain as seen from the south and east.
The sandstones predominate, and make up two quite distinct
members of the upper part of the Chico, with thick beds of
yellow clay shales between. The upper sands of the Chico
are characterized by large sandy concretions of a brown
color, which have a tendency to split horizontally or to fall
apart in concentric shells or laminae.

Thus far species of Inoceramus are the only fossils found
in these concretionary rocks, but Baculites have been found
in close connection with them near the coal mine west of
Coalinfja. The concretionarv sandstone has a maximum
thickness of some four hundred feet where it is exposed nine
miles north of Coalinga. The yellow shales below the con-
cretionary sandstones contain masses of nodular limestone
from which were obtained at different points the following
species:

Baculites chicoensis Gabb Inoceravius zchitneyi Gabb

Baculites sp. Perissolax brevirosiHs Gabb

Lytoceras sacya Forbes Architectonica sp.

Desmoceras (rel. D. hoffmanfii Gahh) Gyrodcs sp.

Pectunculus veatchi Gabb Cimilia obliqua Gabb, etc., etc.

The Chico rocks stand at a high angle all along the range,
and vary in strike to conform to the underlying Franciscan
and other rocks. For the most part all the Cretaceous rocks
strike northwesterly or a little north of west. Perhaps the
averajje strike of the Cretaceous rocks is N. 60° W. How-

l62 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 See.

ever, there are two structural ox-bow curves, one on either
side of Coalinga at a distance of some ten or more miles, in
which the Cretaceous rocks are carried well toward the val-
ley, forming the foundation upon which the Tertiary oil
yielding strata are deposited.

Attention should be directed to these curves as structural
features of the range as a whole, but too little is yet known
of them to warrant more than a suggestion. It appears that
their repetition along the eastern part of the range forms the
axes of local anticlines in the later strata which plunge
respectively below the level of the valley bottom. No less
than six such folds are known between the Sunset district
and the Big Panoche Creek north of Coalinga, but their
fuller discussion must be left for another time.

Eocene Formations.

The Eocene strata of the Coalinga district and vicinity lie
in detached belts alongr the eastern and northeastern flanks
of the range. One of the more extensive belts of Eocene
rocks extends from the northern border of the Sunflower
Valley westerly to the head of Alcalde Creek. Another
begins in the hills west of Coalinga and extends northerly
for two miles or more and includes the coal mines of that
district. A third belt begins north of Los Gatos Creek,
extends northeasterly along the foothills, and can be traced
north and northwesterly in a fairly well marked band for
twelve or fifteen miles to Salt Creek, and thence westerly
to Silver Creek and the Panoche Valley. Northward from
Los Gatos Creek the Eocene forms a fairly uniform and
continuous series as far as it has been followed.

Still another area occurs on the northern border of the
Antelope Valley near the Devil's Den, and includes the
massive sandstones at the place locally termed the Point of
Rocks. A fifth and more southerly area of Eocene occurs
in the near vicinity of Temblor and at Canara Springs and
northward toward the Antelope Valley. At Canara Springs
the massive sandstones of the Eocene form conspicuous and
picturesque cliffs, over which lie the more regular beds of

Geol.— \'oL. II.] ANDERSON—STRATIGRAPHIC STUDY 163

the Lower Miocene. These massive sandstones present
many curious and striking examples of atmospheric erosion,
among which are the natural cisterns often developed on
the summits of the most conspicuous pyramids of rock.

Along the Eocene belt extending westerly from Tar
Springs the rocks stand at a high angle dipping to the north
at an angle of 75° to 80°. In the Coalinga belt they likewise
stand at a high angle dipping toward the east, while farther
north the inclination is less and the strike carries them in a
broad curve around the outer flanks of San Benito Mountain.
The dip naturally varies in its direction with the strike, but
in its inclination it is commonly between 25° and 35°.

While the stratigraphic divisions of the Eocene do not
continue regularly throughout, there is at least one member
that is fairly well characterized along the whole extent of
the series as far as followed. This member is the middle
one, and consists of brown bituminous or carbonaceous
shale, more or less sandy in the lower portion, and with
a maximum thickness of six hundred feet as exposed on
the hills a few miles north of Coalinga. Farther to the
south and southeast it varies considerably, attaining at the
Kreyenhagen wells a thickness of about nine hundred feet,
while on the head of the Jacalitos and on the Zapata Chino
there are not more than two hundred fifty or three hundred
feet of strata. On account of its development at the Krey-
enhagen wells this member of the Eocene has been termed
the Kreyenhagen Shales. The lithological character of these
shales is not constant, as the proportions of the chief elements
vary from point to point. Sands, clay, and organic matter,
both calcareous and carbonaceous, make up the mass of the
beds, which at some points become sandy and at others argil-
laceous, while the percentage of lime or carbonaceous matter
also varies.

Nodular masses of calcareous rock and nodules of barites
( Ba SO4 ) are common in many places, and these form a
characteristic feature of the shales.

The calcareous masses occurring in the shales often con-
tain foraminifera in great numbers, not unlike certain rocks

164 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

of the Miocene. The brown color of these shales is proba-
bly due in large part to bituminous matter contained therein ;
but this will be referred to later.

Both above and below the Kreyenhagen Shales are sands,
which at some points are sufficiently consolidated to form
hard rock.

South of the Kreyenhagen wells there is a great thickness
of sandstone exposed along the canyon of Canoes Creek with
a thin basal bed of conglomerate resting upon the Lower
Cretaceous shales. The strata stand almost vertical with a
dip of 75° or 80'^ toward the north and an east-west strike.

At least the upper four hundred feet of this sandstone,
and possibly all of it, is to be referred to the Eocene. A
few miles to the east, at Tar Springs, the lower portion of
the Eocene consists of about four hundred feet of concre-
tionary sandstones which are very fossiliferous. The con-
cretions occupy a place immediately below the Kreyenhagen
Shales, while lower down are thin beds of sandstone, and at
the base a bed of pebbly conglomerate six to ten feet in
thickness, resting upon strata of Cretaceous age. The Avenal
wells at Tar Springs are drilled to penetrate these sands.
These basal and concretionary sandstones can be followed
for several miles both east and west from Kreyenhagen's,
being exposed at Tar Springs on the east and at the Sulphur
Springs on the Zapata Chino Creek to the west. On account
of their development at the Avenal wells (Tar Springs) they
may be conveniently termed the Avenal Sandstones.

The species of invertebrate fossils obtained from these
sandstones include the following:

Cardita horni Gabb ( C. planicosta Architectonica horni Gabb

Conrad) Ancellaria elongata Gabb

Cardiiitn cooperi Gabb Dentalium cooperi Gabb

Cardita sp. Fusus martinez Gabb

Corbula paratis Gabb Fusus diaboli Gabb

Solen paratellus Gabb Turritetta uvasana Gabb

Meretrix horni Gabb Turritetta pacheco'ensis Stanton

Amauropsis atveata Gabb Neverita gtobosa Gabb

A stratigraphic section of the rocks at Tar Springs is
shown in the accompanying sketch (PI. xxxiv, fig. i).

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY 1 65

At the sulphur spring in one of the canyons of Zapata

Chino Creek the Eocene is represented by the following

members :

ft.

Kreyenhagen Shales 250

Avenal Sandstones 500

Basal conglomerate 15

It will be seen that the Kreyenhagen Shales are consider-
ably reduced in thickness while the Avenal Sandstones are
somewhat thickened, but the latter was proved by the con-
cretionary masses, by the basal conglomerate, and by fossils.
The entire series stands at a high angle with a westerly
strike and a dip to the north.

The Eocene could not be traced westerly beyond the
Sulphur Springs on the Jacalitos Creek.

At the Point of Rocks on the northern border of the Ante-
lope Valley there are about twenty-four hundred feet of
Eocene strata exposed, the lowest beds of which contain the
following species :

Neverita globosa Spondylus carlo sensis n. sp.

Turritella uvasana Cardita

Discoheli.v Terebratella

Meretrix uvasana Sea urchins
Ostrea idriaeusis

These beds dip northeaster^ at an angle of near 30°, and
to the eastward are overlain by the sandy beds of the Lower
Miocene. The upper one-third of the Eocene consists of
sands which include exposures like that shown on Plate xxvii.
Between the fossiliferous concretionary sandstones forming
the lowest beds exposed and the massive sand beds above,
there are softer and less resistant beds that perhaps represent
the shales which form elsewhere the intermediate member.

At Temblor and Canara Springs the massive sands are
exposed, but the shales and fossiliferous beds below were
not identified. The unconformity of the Lower Miocene
beds upon these massive sands of the Eocene is well shown
on Plate xxv.

In the areas extending northward from Coalinga the
Avenal Sandstones have been only indirectly proved. At

i66

CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

the coal mines the basal portion of the Eocene is occupied

by thin beds of conglomerate, sand, and coal-bearing sandy

shale. The following stratigraphic section fairly represents

the Eocene at the coal mines:

ft.

Kreyenhagen Shales 400

Echinoderm conglomerate 8

Carbonaceous sands 140

Two fossil horizons are to be noted in this section: (a)

that of the pebbly conglomerate containing species of

Echinoderms; (b) that of the carbonaceous sands. The

thin bed of conglomerate has afforded the following species :

Cassidiilus californiciis n. sp. Spondylus carlosetisis n. sp.

SciUella sp. A. Tellina sp.

Echinoderms (genus not det.) Galenis excentricus Gabb

Ostrea aviculiforniis n. sp. Turritella tivasaiia Gabb

Cardiuni cooperi Gabb Terebratella sp.

Mactra sp. Crustaceans (Cancer, etc.)

Meretrix honii Gabb Nodules of barites

Ostrea (2 sp.)

From the sandy beds more closely connected with the

coal and carbonaceous strata were obtained :

Modiola ornata Gabb Ostrea idriaensis Gabb

Meretrix uvasana Gabb Limatia horni Gabb

Meretrix horni Gabb Nerita triangulata Gabb

Cardium cooperi Gabb Neverita globosa Gabb

Mactra sp. Galerus excentricus Gabb

Area ( Barbatia ) inorsei Gabb Fusus niartinez Gabb

Cardita sp. Turritelta pacheco'ensis Stanton
Placiianoniia inornata Gabb

North of Los Gatos Creek a pebbly conglomerate, si.x to

ten feet thick, near the top of the Kreyenhagen Shales, has

been followed almost continuously for a distance of four

miles. It has yielded the following species :

Ostrea aviculiformis n. sp. Morio tiiberculatiis Gabb

Cardita horni Gabb Turritella uvasana Gabb

Dositiia sp. Turritelta pacheco'ensis Stanton

Gari texta (?) Gabb Trochosmitia striata Gabb

Cardiuni cooperi Gabb Ellipsosuiilia granulifera Gabb

Pecten sp. Terebratella sp.

Meretrix horni Gabb Echinoderms (2 sp. undet.)

Ostrea (2 sp.) Sharks' teeth

Spondylus carlosensis n. sp. Teleost. vertebrae

Amauropsis alveata Gabb Nodules of barites

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY 167

On the N. E. ^4^ of Sec. 17, north of Coalinga, similar
pebbly beds just above the top of the Kreyenhagen Shales
contain a few of the foregoing species along with species of
Foraminifera and nodules of barites.

This horizon of the Eocene begins its greater development
at this point and increases in thickness as it is followed to the
northwest. On the east side of Section 17 it has a thickness
of not more than three hundred fifty feet, while eight miles
to the northwest it has a thickness of something like twelve
hundred feet, where it is exposed in the vicinit}' of the Kim-
ball wells.

It consists chiefly of yellow sands, which, as far as they
have been followed, are but little consolidated, and under
the meager rainfall of the region readily disintegrate, forming
loose sandy slopes. Its great development in the vicinity of
the Domijean ranch affords grounds for its designation as
the Domijean Sands.

On the west side of Section 17 the sandy beds at the base
of the Eocene aggregate somewhat more than at the coal
mine, but they are also more distributed stratigraphically,
with shales intei"vening between their several layers.

They are partially represented on Plate xxxiv, figure 3.
Their correlation with the Avenal Sands is based chiefly
upon tlieir stratigraphic position, as they are undoubtedly
basal and rest directlv upon the concretionary Chico sand-
stones.

In the vicinity of New Idria and along the southern side of
the Big Panoche Valley the Eocene rocks present the stratig-
raphy characteristic of the series north of Coalinga. Three
members are clearl}- distinguishable, though their aggregate
thickness can hardly exceed twelve hundred feet. The beds
may be divided as follows :

ft.

Loose ash-colored sandstones 300

Carbonaceous clay shales 300

Sandstones (ash-colored) 600

Total 1200

The Eocene age of these beds appears to have been at

1 68 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

least suspected by Gabb, as shown in Whitney's' discussion
of the region.

The stratigraphic members of the Eocene, then, are the
following :

Domijean Sands

Kreyenhagen Shales

Avenal Sandstone

The lack of continuity of these members along the entire
range is to be attributed partly to their nature and manner of
origin, and partly to their degradation previous to the laying
down of the succeeding Miocene or Pliocene strata ; naturally,
therefore, this lack affects chiefly the lower and upper mem-
bers, while the intermediate member is more uniform in its
character and at the same time more persistent in its occur-
rence.

The preceding lists of fossils contain representative Eocene
species such as indicate that the beds are to be correlated
rather with the Tejon than with the Martinez division of the
Eocene, and this accords with the fact that the latter horizon
has been considered local in its occurrence, or extending
only northward from the latitude of Mount Diablo, and also
with the fact that the Tejon Beds are found at New Idria and
other points only a few miles north of the limits of our own
observations.

Miocene Formations.

Rocks of the Miocene period do not enter extensively into
the stratigraphy of the San Carlos Division of the range
north of Alcalde Creek, but south and east of this stream
they are more in evidence. Miocene strata occur in some-
what disconnected belts running parallel with the Eocene,
and to some extent parallel with the Cretaceous. The
greatest thickness of Miocene rocks found in any part of the
range is near McKittrick and Temblor, although thicker
aggregations of strata are found elsewhere, as on the western
border of the Carisa Valley.

1 Geo!. Surv. Calif. Geol. v. i, p. 57.

Geol.— Vol. II.] ANDERSON^STRATIGRAPHIC STUDY 169

The most representative section of the Miocene that has
been observed anywhere in the range south of the Cantua
Creek is to be seen at Temblor and Canara Springs in west-
ern Kern County. Though no detailed study of these strata
was undertaken, a general statement will be found interesting
and instructive. The most conspicuous member of the
Miocene in this section is the Monterey Shales, which have
here an aggregate thickness of more than five thousand feet.
For the most part this member consists of light colored
shaly strata, the material of which is evidently largely
organic, but in which three or more elements are easily
recognizable; viz., foraminiferal limestone, siliceous organic
beds, clay shales, and supposedly volcanic dust and ash.

The limestone occurs in thin lenticular bands, gray or
yellowish in color, in which Foraminifera are readily seen
through a good lens. These yellow or light gray bands
occur in groups or singly, scattered through the entire
thickness. The siliceous portion of the Monterey Shales
predominates, and generally shows remains of Diatomaceae
and other siliceous organisms, with bones and scales of fishes.

Near the top of the series the strata become more chalky
and softer. Pecten peckhami has been found at both the top
and bottom of this member at Canara Springs and eastward.
The Monterey Shales, apparently, in undiminished thickness,
make up the mass of the main range west of McKittrick,
but they have not been traced easterly much beyond the
Sunset district.

Underlying the Monterey Shales at Canara Springs and
Temblor are sandstones and sandy shales which make up
an additional thickness of fifteen hundred feet. The entire
series., of Miocene rocks at this point is about as follows :

ft.

Monterey Shales 5500

Sandstones with Astrodapsis 100

Siliceous and clay shales with interstratified sandstone 600

Sandstones with numerous fossil species 800

Total thickness 7000

The sandstone with Astrodapsis contains in addition Pecten
nevadensis, Pecten discus, and a few fragments of oysters and

lyo CALIFORNIA ACADEMY OF SCIENCES [Proc. 3D Ser.

barnacles. The lower fossiliferous sandstones yielded the
following species of invertebrates :

Lucina borealis Linn. Pecten sp.

Lucina richthofeni Gabb Solen sp.

Yoldia cooperi Gabb Tapes sp.

Mytilus tnathewsoni Gabb Maconia sp.

Chione niatheiusoni Gabb Ballauus sp.

Dosinia mathewsojii (?) Gabb Neverita callosa Gabb

In the light of stratigraphic studies farther north it is
evident that the entire series of sands and shales below the
Monterey Shales should be regarded as a distinct member of
the Miocene, and the name Temblor Beds is suggested to
embrace this aggregate of strata, while for the first sandy
beds below the Monterey at Temblor the name " Button
beds" has been used on account of the great numbers of
small discoidal sea urchins (^Astrodapsis) which characterize
them here and elsewhere.

The Temblor Beds are often characterized by sands,
more or less distinctly stratified, which are usually rendered
highly calcareous by great numbers of fossil invertebrates.
Echinoderms are sometimes so abundant that certain beds
become almost a limestone. Occasionally pebbly layers are
encountered, and at other points the sandstones become
noticeably shaly.

As will be noticed further on, it is not rarely that the
Monterey Shales are found resting on older rocks without
any appearance of the Temblor Beds intervening. In some
places there is a distinct overlapping of the Monterey Shales
beyond the borders of the Temblor Beds.

North of the Canara Springs there is no similar thickness
of Miocene strata anywhere in the Mount Diablo Range as
far as known to the writer. In the vicinity of the Devil's
Den and northward the section is materially reduced, chiefly
by the reduction of the Monterey Shales.

Nowhere north of the Antelope Valley have these shales
been found to exceed one thousand feet in thickness, though
otherwise they are identical and appear to represent the
basal portion of the shales occurring in the Canara Springs
section.

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY I'JI

Miocene strata describe a broad curve around the eastern

side of the Sunflower Valley, but at most points only the

Monterey Shales are visible. On the northern border of the

Sunflower Valley, at Tar Springs, the Miocene section is

about as follows :

ft.

Monterey Shales 900

Temblor Sandstones with fossils 800

White sandy shales 400

Total 2100

This section is representative of the Miocene occurrences
at most points between the Antelope Valley and Alcalde
Creek. The Miocene rocks rest indiscriminately upon the
Eocene, the Cretaceous, or older rocks as the case may be,
though not always with an appearance of unconformity.
The dip is always toward the Great Valley at some angle
between 20° and 90°. At Tar Springs the dip is above 75°.
At the Devil's Den on the south side of the Sunflower
Valley the dip is in some places anticlinal, and to the west of
the valley the Monterey Shales rise upon the flanks of the
main range, overlying the Cretaceous without any appear-
ance of the Temblor Beds.

The topographic aspect of the Temblor Beds is striking.
They stand out in bold relief along the whole range from
McKittrick northwestward to near Coalinga, and form a
species of serrated wall along the front of the hills through
which the canyons emerging into the Great Valley have cut
their ways. This is particularly noticeable along the north-
ern border of the hills extending west from Tar Springs, and
in many other parts of the country. This feature is shown
in some degree on plates xxviii and xxix.

The following fossil species have been collected from the
Temblor Beds at different points :

Tar Springs.

Sciitella sp. Neverita callosa Gabb

Astrodapsis nierriami n. sp. Dosinia ^natheivsoni (?) Gabb

Pecten discus Conrad Crepidiila praerupta Conrad

Pec ten crassicardo Conrad Ballanus sp.

Turritella ocoyana Conrad

[2] November 28, 1905

172

CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

Kreyenhagen Wells.

Astrodapsis nierrianii n. sp.
Pecten discus Conrad
Pecten estrellanus Conrad
Turritella ocoyana Conrad
Agasoma graviduni Gabb
Neverita callosa Gabb
Mactra densata Conrad
Venus {Chione) tanblorensis n. sp.
(rel. C. guidia.)

Zirphaea sp.

Natica sp.

Mactra {Spisula) sp.

Ostrea sp.

Hemifiisus wilkesana n. sp.

Lticina acutilmeaia Conrad

Area moiitereyana Osmont

Balla?ius sp.

Sulphur Springs, Zapata Chino Creek.

Mactra densata Conrad
Mactra sp.

Area montereyana Osmont
Tapes sp.

Lucina sp.

Venus ( Chione) temblorensisn. sp.

Astrodapsis merriami n. sp.

The species given in the preceding lists are characteristic
of the Lower. Miocene as it occurs in the Great Valley of
California, and perhaps that of all the interior valleys of the
State.

The more northerl}^ belt of Miocene rocks in the Coalinga
district begins a few miles to the northwest of Coalinga, on
the north side of Sec. 2, T. 20 S., R. 14 E., and extends in
a broad curve northeasterly, northerly, and northwesterly for
many miles, or quite beyond the Cantua Creek.

It is fairly well shown on the Coalinga geologic map pre-
pared for this paper (PL xxxv). The dip of the strata is
always toward the Great Valley at angles varying from 20°
to 35°, and in directions normal to the strike. In a few cases
only, and notably in one or two cases, is the structure com-
plicated. In the main the structure of all the Tertiar}^ rocks
is monoclinal. But on the S. E. % of Sec. 20, T. 19 S.,
R. 15 E,, the Miocene rocks are exceedingly crushed and
distorted by compression, and to some extent this distortion
extends also to the Eocene and the Pliocene rocks.

Two members of the Miocene have been detected in the
Coalinga district proper, but possibly others occur a few
miles to the northwest. For the most part the Temblor Beds
are not present, and the following members only are in

Geol.— Vol. II.] _ ANDERSON— STRATIGRAPHIC STUDY 1 73

evidence, as in the vicinity of the Kimball wells, where the
following members occur:

ft.

(?) Contra Costa Beds

Monterey Shales 800

Domijean Sands (Eocene) 1200

Ashy beds near the top of the jNIiocene resemble both litho-
logicall}' and faunally beds on the baj^-shore north of Pinole
Station, Contra Costa County. The following species were
collected from these Miocene beds on the west side of Sec. 19,
T. 18 S., R. 14 E.:

Ashy beds. ]Monterey Shales.

Leda oregona (?) Pecten peckhaini Gabb

Tellina congesta ( ?) Callista ( ?) sp.

The Miocene rocks show little evidence of beincf bitu-
minous as they are followed northward toward the Cantua
Creek, and in fact there is but slight direct evidence that
they are bituminous at any point between Coalinga and the
Cantua.

The noteworth}- facts about the Miocene series north of
Coalinga as far as followed are the absence of the Temblor
Beds and the greatly reduced thickness of the Monterey
Shales. Strata of apparently the horizon of the Temblor
Beds occur in the Walnut Creek Valle}' west of Mount
Diablo, as described by Dr. Merriam.^

Later Neocene Beds.

By far the most important series of strata in the Mount
Diablo Range from the view-point of economic geology are
the late Tertiary strata, including the probable equivalents of
the San Pablo Beds and others with which they are uncon-
form.ably related. In this collection of strata the following
members are distinguishable, either stratigraphically or fau-
nally :

1 Bull. Dept. Geol. Univ. Calif, v. 3, pp. 377-381.

174 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

Etchegoin Beds j San Joaquin Clays

(San Pablo Beds ?) I Etchegoin Sands

Coalinga Beds \ Oyster Sands, etc.

( Reef Beds, etc.

Each of these divisions could be again subdivided with
greater or less success w^ithin specified limits, but it would be
difficult to discover features characteristic enough for such
purposes that would have a wide application. In other words,
the materials of the strata change more or less from point to
point along their strike, passing from coarser to finer, etc.,
according to local conditions during the period of their depo-
sition, such as the presence of streams, currents, etc.

The most constant feature of the lower two-thirds of the
combined series is its sandy character, while the upper por-
tion is clay or fine sand and clay, in which the clays are
variegated in color, being alternately white, red, gray, or
yellow.

Co a Ibiga Beds .

An interesting stratigraphic unit is that here described
as the Coalinga Beds. So far they have been found only
locally, and throughout a stretch of more than fifty miles
along the Mount Diablo Range they were not recognized
at all. They occur, however, in both the Coalinga and
McKittrick districts, and in each case sufficiently individual-
ized to be regarded as distinct from both the Monterey and
the Etchegoin Beds.

In the Coalinga district, as shown on the map (PL xxxv),
the formation occurs in two separate areas, the more north-
ern of which can be followed far beyond the limits of the
map, or at least to the Cantua Creek if not to Mount Diablo.

West of Coalinga these beds are sandy with a minor part
of shale, which at one place north of the coal mine appears
to be soft and marly if not diatomaceous. At the artesian
water well on Section 35 these marly beds do not appear,
but the basal beds are composed of sands which are locally
bituminous. Six miles north, on the E. J^ of Sec. 36 marly
beds crop out very near the base and present also a strongly

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY

175

bituminous appearance in their yellow red, and brown dis-
colorations. The stratigraphic position of these white marly
beds can be well observed at many points, as on the south
side of Sec. 20, T. 19 S., R. 15 E., where a conspicuous
reef of sandstone crosses the ravine, with marly beds both
above and below. This sandy stratum, on account of its dis-
position to protrude here into a sort of wall, and from the
fact of its being fossiliferous, was during our field-study
termed the J^eef Bed, and it proved a useful name in further
exploration. The accompanying sections show the principal
stratigraphic features of the Coalinga Beds at two or more

points:

ft.

Yellow sands, etc 1300

Tamiosoma Bed with oysters, pectens, etc... 20

Yellow sands 550

White shale (marly) 20

Dark sands 50

Reef Bed 40

White shale with oysters 20

Basal sands, etc 180

Coalinga Beds ten miles
north of Coalinara

Coalinga Beds twenty
miles northwest of -
Coalinga

Coalinga Beds three
miles west of Coal-
inga

Yellow sands 1000

Sands with oysters 6

Sandy white shales 80

Tamiosoma Bed with oysters, pectens, etc... 15

Yellowish sands, gravels, etc 320

Reef Bed (sandy) 15

Basal sands and conglomerate 120

Blue sands, gravels, etc 2400

Pecten beds 40

Sands, gravels, etc 700

Sands and yellow gravels 1000

Dark sands with Diplodonta harfordi. 50

Reef Bed (sand stone) 50

Gray sands, unconsolidated 200

1 Basal gravels 50

It will be seen by an inspection of these sections that there
is throughout the field but little continuity to any of the litho-
logic features that seem locally to be significant, as gravels
give place to sands, and both become locally calcareous, or
the reverse.

A somewhat more satisfactory means of correlating or
identifying strata is found in the faunal contents as illustrated

176 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

in the case of the Reef Bed, from which the following species
have been obtained where the bed can be traced continuously
for two or three miles through Sec. 16, 21, and 20; T. 19 S.,
R. 15 E.

Reef Bed, Sec. 20 and Sec. 21 :

'^ Astrodapsis iumidus Reniond * Tapes tenerrima Cpr.
*Arca montereyana (?) Osmont Lucina borealis Linn.

* Dosinia ponderosa Gabb *Pseudocardium sp.
*Mactra {Spisula)/a/cata (?) Gould *Neverita recluziana Desh.

Macoma inquinafa (?) Desh. Hemifusus sp.

Mvtilus californianus Conrad * Trophon gabbiana n. sp.
*Pecten discus Conrad Trochita sp.

Pec ten estrellanus Conrad Sharks' teeth

The more characteristic of these species were found in the
Reef Bed of Sec. 20, T. 18 S., R. 14 E., including:

*Pectefi discus Conrad * Dosinia po?iderosa Gabb

* Astrodapsis Iumidus Remond

A Stratum in the last section immediately above the white
shales, four hundred feet above the Reef Bed, contained the
following species and genera :

Cytherea ( Callista) sp. Soleti sp.

Chione (rel. C. guidia) Ostrea sp.

Macoma nasuta Cpr. Agasoma kernianum Cooper

Pecten estrellanus Conrad Turritella sp.

Zirphaea dentata Gabb Cancellaria sp.

Lucina borealis Linn. Trophon sp.

Diplodonta harfordi n. sp.

It is apparent that not onl}^ are the characteristic Reef Bed
fossils absent from this list, but there are some forms intro-
duced, as for instance the first two and nearly all of the
gasteropod species.

The Oyster sands, with their associated gigantic Tamiosomay
Pecten, etc. are well developed on the N. E. Yx of Sec. 19, T.
18 S. , R. 14 E. , and can be easily followed toward the south-
east to the vicinity of the wells of the California Limited Oil
Company.

Another feature of the basal portion of the Coalinga Beds
between Salt Creek on the north and the wells of the Cali-

NoTE. In the above and following lists important or characteristic species are marked
with an asterisk.

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY 1 77

fornia Limited Oil Company is the rather local development
of heavy beds of conglomerate. These are best seen in the
" Rainbow beds" on Sec. 4 and 10 ; T. 19 S., R. 15 E. and
in the conglomerates crossing Salt Creek, Sec. 10, 11, and
14; T. 18 S., R. 13 E.

These conglomerates vary considerably in thickness, having
their maximum development on Salt Creek, where there are
above the Reef Beds about twelve hundred feet of heavy
serpentine conglomerate. The conglomerates, including the
" Rainbow beds," lie between the Reef Bed below and the
Tamiosoma bed above, and as far as they have been followed
they hold this relation, but at intervals give place to sandy
beds, as in the case south and west of the California Limited
Oil Company's wells.

West of Coalinga the Reef Bed is not a prominent topo-
graphic feature, but it can be recognized by its faunal con-
tents, which contains the following species:

*Dosinia ponderosa Gabb Pecten estrellanus Conrad

"^Cyrefta calif ornica Gabb Zirphaea dentata Gabb

Crepidiila excavata (?) *Mactra {Spisula) catilliformis

*Cytherea {CalHsta) sp. (rel. C. Dall

callosa) *Mactra {Spisula) falcata Gould

Mytilus californianiis Conrad *Neverita recluziana Desh.

Lucina borealis Linn. *Chrysodomus recunia Gabb

*Metis {Lutricola) alia Conrad Purpura sp.

Maconia nasuta Cpr. Galerus sp.

Cytherea ( CalHsta) diabloensis Cancellaria vesper Una n. sp.

n. sp. Nassa sp.

* Tapes tenerriina Cpr. *Trophott sp.
Diplodonta harfordi n. sp. *Astrodapsis sp.

* Pecten discus Conrad

i Oxyrhina tumula Agz.

Vertebrates ^ Lantna clavata Agz.
r Zyg abates sp. Agz.

It is not unlikely, and is perhaps even probable, that the
Coalinga Beds as here described will be found to be the
equivalent of the Contra Costa Beds described by Merriam^
as belonging to the uppermost Miocene. Their noncon-
formity' with both the Monterey Shales below and the char-
acteristic Etchegoin Beds above is clearly shown, as pointed

Bull. Dept. Geol. Univ. Calif, v. 3, no. 16.

178 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

out by Mr. Owen, in the foothills directly north of Coalinga.
It is also a significant fact that for more than sixty miles
along the eastern side of the range, between Coalinga and
McKittrick, they do not appear, though the Monterey Shales
and the Etchegoin Beds are continually in evidence.
Throughout the Salinas and other intermontane valleys to
the west, the Coalinga Beds appear to be present in con-
siderable thickness.

Etchegoin Beds.

No other formation in the Mount Diablo Rangfe has so
great an areal extent and so great a thickness and continuity
as the Etchegoin Beds, which overlie in turn all of the
older formations of the region, resting upon each respec-
tively with a distinct nonconformity. The relations of this
formation to the others in the Coalinga field are shown in
the accompanying map (PI. xxxv) and sections (PL xxiv).

The maximum stratigraphic thickness of the Etchegoin
Beds in their greatest development is certainly not less than
seventy-five hundred feet, while at other points they do not
exceed five thousand feet. In some sections they have the
appearance of aggregating the incredible thickness of nine
thousand feet, but such a development is probably local.

Sands, usually but little consolidated, form the predomin-
ating element and make up locally three-fourths of the
entire series, occurring chiefly at the bottom or in the lower
portions.

The name of this formation has been derived from its
characteristic development in the vicinity of the Etchegoin
ranch, some twenty miles northeast of Coalinga.

A detailed description of the divisions of the Etchegoin
Beds is hardly possible from our present knowledge of them,
but a general statement will perhaps be useful in identifying
them in the field and in correlating them with similar forma-
tions elsewhere.

Etchegoin Sands. — Occupying a stratigraphic position
at the base of the Etchegoin and forming almost two-
thirds of its mass, are unconsolidated sands or gravels in

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY 1 79

which a characteristic blue or bluish gray color predomi-
nates, at least in certain localities. In the vicinity of the
Etchegoin ranch, some twenty miles northeast of Coalinga,
these blue sands are distributed in three prominent horizons
including about twelve hundred feet of strata. They can be
traced with more or less continuity throughout the field from
the Cantua southward to the Sunflower V'alley.

The blue color has been generally found to be a safe
index to the identit}^ of the beds and has been recognized in
the vicinity of Mount Diablo and on San Pablo Bay. It is
not claimed, however, that it is constant or characterizes any
particular strata within this division. In thickness the
Etchegoin Sands vary considerably. Near the Cantua
the thickness appears to be less than on the Etchegoin
ranch, while south of Alcalde the thickness is considerably
greater.

In the vicinity of Kreyenhagen's where the Etchegoin has
its greatest development, the strata included within the limits
of the blue sands are twenty-five hundred feet, of which
ordinary gray sand and gravels form the larger portion. Many
of the pebbles are jet black in color.

The Etchegoin Sands are commonly coarse in texture and
often pebbly, forming beds of conglomerate. There is an
appearance of volcanic ash or Kaolin-like matter throughout
the colored zones, and their characteristic color may be
partly due to this material, but the exact nature of the color-
ing matter has not been determined.

One or two fossil horizons are to be recognized in the
Etchegoin Sands, one near their bottom and another some
distance above, but whether persistent or not cannot be
stated. The more characteristic horizon is that near the
bottom of this division and includes the following species:

Pseudocardiurn gabbi Remond Scute lla sp.

Area trilitieata Conrad Mytilus (large sp. )

My a arenaria Linn. Ostrea attwoodi Gabb

Pectunculus sepientrionalis Midd. Cardium meekiatimn Gabb

The second fossil horizon occurs higher up in the beds,
nearer their top, and contains the following:

i8o

CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

Area trilineata Conrad
Saxidomus aratus Gould
Pecten coalinga'ensis Arnold
Pecten wattsi Arnold
Pecten etchegoini n. sp.
Chania sp.
Ostrea sp.
Tellina sp.
Ballanus sp.

Neverita recluziana Desh.
Nassa californica Conrad
Terebratella sp.
Clype aster {Scut ell a) brcweriana

Remond
Scutella gibbsi Remond
Astrodapsis tumidus Remond
Sharks' teeth, etc.

Southward on the Jacalitos Creek similar beds near the
base of the Etchegoin series contains the following species :

*Mactra {Mulinia) densata Conrad Pecten crassicardo Conrad

*Mactra {Spisuta) falcata Gould
* Metis {Lutricola) alia Conrad

Macoma nasuta Cpr.

Pectunculus septenti-ionalis Midd.

Saxidomus aratus Gould

*Hinnites sp.

* Trophon ponder o sum Gabb

* Chrysodomis sp.
Nassa sp.
Natica sp.

West of Coalinga where the Etchegoin Beds are well
exposed and fossiliferous, they contain:

Mactra {Spisuta) falcata Gould
Metis {Lutricola) alta Conrad
Saxidomus aratus Gould
Tapes staleyi Gabb
Pecten oweni Arnold
Area trilineata Conrad
Pectunculus septentrionalis Midd.
Cardimn meekianunt Gabb

Diplodonta harfordi n. sp.
Macoma secta Conrad
Pseudocardium sp.
Nassa californica Conrad
Neverita recluziana Desh.
Pleurotoma {Surcula) sp.
Scutella gibbsi Remond, etc.

A comparison of these lists with the lists published by
Whitney^ and others for the Pliocene occurring at Kirker's
Pass, Contra Costa County, makes it evident that faunally
they are of the same group of strata. Furthermore a few
days spent by the writer in studying and collecting from the
beds occurring on the east shore of San Pablo Bay, Contra
Costa County, led to the conclusion that the two thousand or
more feet of Pliocene strata occurring there on the southern
side of the syncline is the equivalent of the Etchegoin Sands
and represents only the basal portion of the Etchegoin Beds
in their full development. The same fauna can be recog-
nized also a little to the north of Walnut Creek Station on
the railroad running to San Ramon. The lowest faunal

Geol. Surv. Calif. Geol. v. i, p. 32.

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY l8l

horizon on San Pablo Bay is equivalent to that of the lowest
horizon described in the Etchegoin Sands. Among the more
characteristic species are the following, from the bay-shore
north of Pinole :

Astrodopsis turnidus Remond Mactra falcata Gould

Pecten pablo'cnsis Conrad Pectunculiis seplentrionalis Midd.

Pecten crassicardo Conrad Saxidomus aratiis Gould

San Joaquin Clays. — The clays at the upper part of the
Etchegoin, from Coalinga northward, occupy at least a third
of the entire series, or about fifteen hundred feet in strati-
graphic thickness. At a distance these clays present a
banded appearance from the zones of color seen in the dif-
ferent strata, some of which have a width of two hundred or
three hundred feet. These clays are overlain by fresh water
deposits in the vicinity of Tulare Lake and the Kettleman
Hills to the depth of one thousand feet or more.

No fossils have been found in them north of Coalinga,
but north of Tar Springs, Kings County, specimens of Scu~
tella o-ibbsi and teeth of sharks have been found.

^>'

Tulare Formation.

Overlying the San Joaquin Clays of the Etchegoin series
there are thick strata of gypsiferous sands and clays exposed
at intervals along the western border of the Great Valley.
In the Kettleman Hills, ten to fifteen miles southeast of Coa-
linga and near the western shore of Tulare Lake, these beds
aggregate fully one thousand feet in thickness, though no
attempt was made to measure them accurately. They lie
conformably upon the San Joaquin Clays and in some
respects resemble them, so that it is not always possible to
discriminate accurately betw^een them. Where the Tulare
beds are exposed in the Kettleman Hills they have been
noted by W. L. Watts S who gives a sectional view of the
Pliocene beds with which he classes these. Some of the
beds contain an abundance of fresh -water mollusks, and

1 Bull. no. 3, Calif. State Min. Bur. 1894, p. 55.

l82 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

among those collected by Watts the following species were
identified by Dr. J. G. Cooper:

Anodonta decurtata Conrad Margaritana subangulata Cooper

Anodonta nuttaliana Lea Physa costata Newcomb

Amnicola turbiniformis Tryon Planorbis tutnens Carpenter

Carmifex newberryi Lea Sphaeriuni dentaiutn Hold.
Goniobasis occata Hinds

Their classification as Pliocene is perhaps supported only
by their conformable position on the Etchegoin claj'S, but in
view of the fact of their fresh-water origin, the determination
is not conclusive.

Similar beds are also described by Watts ^ from the vicinity
of McKittrick (Sec. 34, T. 30 S., R. 22 E.) where the
following species were obtained :

Anodonta nuttaliana Lea
Carinifex newberryi Lea
Poinatiopsis intei'media Tryon

It has been suggested that these beds might be correlated
in part or whole with the Orindan beds described by Dr.
Lawson^ from the Berkeley Hills and other points in Contra
Costa County. If such be the case their occurrence is prob-
ably continuous along the whole western border of the
Great Valley, and probably also to the north of the Straits
of Carquinez.

Stratigraphic Relations.

With few exceptions, notably that of the later sedimentary
beds desiffnated as the Tulare Formation, the entire collec-
tion of stratified rocks described in the foregoing pages is
essentially marine. While the coal beds of the Eocene may
represent a condition somewhat different, it is evident that
these beds are local and have not a great stratigraphic range.

In the case of all the later series, beginning with the Creta-
ceous, there is a considerable uniformity of strike and dip in
many parts of the range. From stratigraphic evidence alone

1 Bull. no. 3, Calif. State Min. Bur. 1894, p. 49.

2 Bull. Dept. Geol. Univ. Calif, v. 2, pp. 371 et seq.

Geol.— Vol. II. ] ANDERSON— STRATIGRAPHIC STUDY 183

it is often impossible to discriminate between the rocks of the
several periods. In most places there is an apparent strati-
graphic conformity between Cretaceous and Eocene, and
between the latter and Miocene strata. And in most sec-
tions, likewise, the Pliocene (Etchegoin) rocks rest conform-
ably upon the older series. Dr. Becker and C. A. White ^
believed that the entire collection of Cretaceous, Eocene,
and Miocene strata formed a continuous and conformable
series, and this opinion was held after observations had
extended over a considerable portion of the Mount Diablo
Range. •

The lithological variation of the rocks is considerably
greater, and characteristic types are the rule in all of the
principal epochs. It is often possible to recognize without
the aid of fossils many of the typical members of the strati-
graphic groups. Probably the most trustworthy guide for
the identification of strata in all cases is that afforded by
paleontology, but in the later formations the persistence of
some of the fossil forms from the earliest Miocene to the
Present makes it necessary to use them with caution. With-
out the aid of other stratigraphic data and the recognition of
lithologic peculiarities it would often be difficult to distin-
guish between the Lower Miocene and the Coalinga Beds,
while both of these series contain forms that are still living
alonjj the west coast. However, there are a few forms that
have been found to be sufficiently trustworthy within provin-
cial limits, but it is doubtful if many of them would support
extensive generalizations.

Dr. Merriam has pointed out" that Agasoma gravidum,
Tjirritella ocoyana, and T. hoffjnanni are characteristic of the
lower Miocene, and all of these have been found in the Tem-
blor Beds of the Mount Diablo Range, along with man\- other
forms occurring in the typical Lower Miocene beds of Kern
River.

Similarly certain forms of Pecteii, Mactra, Scutella, and
Astrodopsis are believed to belong only to the Etchegoin
Beds, but it will require at least a reasonable degree of

1 Bull. no. 15, U. S. Geol. Surv. pp. 14, 15 et seq.

2 Bull. Dept. Geol. Univ. Calif, v. 3, pp. 377-38i-

184 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

specific discrimination to maintain this generally, as several
forms of each occur at intervals from the early Miocene to
the Present. Pseudocardimn gabbi of the Pliocene resembles
Midiiiia densata, occurring in both the Upper and Lower
Miocene, and in like manner closely allied species of Saitella
and Astrodopsis occur in both the earl}- Miocene and the
San Pablo.

There is evidence of nonconformity between the rocks of
all of the successive periodic series, and in some cases
between the different members of the same series. The
nonconformity between the Chico and Eocene is well shown
by a detailed study of the field north of Alcalde Creek.
The nonconformity is both stratigraphic and faunal, but the
evidence of either class becomes more convincing only as it
becomes better known. In the case of the Eocene and Mio-
cene nonconformity the evidence is also both faunal and
stratigraphic, the latter appearing more satisfactory from the
fact that the Lower Miocene rests in turn upon the Eocene,
the Cretaceous, and the Franciscan rocks.

The relations of the Pliocene (Etchegoin) formation to
the earlier ones has been shown in the preceding pages and
on the map of the Coalinga district (PI. xxxv), but the evi-
dence shown there is only partial.

What evidence the field might afford as to the relation of
the Etchegoin to later rocks has not been ascertained, beyond
the fact of a transition from marine to fresh-water conditions.
It is conceivable that such a transition might be effected so
gradually by normal causes that no stratigraphic noncon-
formity would exist, but such a transition in this case requires
to be shown. In the Berkeley Hills the Orindan Formation
rests unconformably upon the Monterey Shales, and their
basal portion is pebbly conglomerate. If the Tulare Beds
are to be correlated with the Orindan, the individuality in
each case would be the same.

There is, however, a stratigraphic member still to be con-
sidered, whose exact relationship is less evident, though
probably not so difficult as it might appear. This remark
concerns the Coalinga Beds. They have been followed

Geol.— Vol. II. ] ANDERSON— STRATIGRAPHIC STUDY 1 85

throughout a distance of twenty miles along their outcrop,
where they are almost entirely uncovered, regularly stratified,
and quite fossiliferous. Where they rest upon the Monterey
Shales, which for the greater part of the distance they do,
there is but little appearance of stratigraphic divergence,
except an abrupt transition from fine to coarse sediment. In
their dip and strike there is considerable uniformity, at most
points at least, though there is at some points a sudden
change from the hard shales of the Monterey to the soft
coarse sands and conglomerates of the Coalinga Beds. As
they are followed along their contact, however, as they can
be easily for many miles, the Coalinga Beds are not only
found resting upon different portions of the Monterey at dif-
ferent points, but toward the south they rest in turn upon
Monterey Shales, the Eocene, and the Chico.

The nonconformity therefore of the CoaHnga Beds with
all of these older series may be considered equally clear.

The stratigraphic nonconformity of the Coalinga Beds,
on the other hand, with the Etchegoin Beds is also equally
clear.

This is best shown near the northeast corner of the map of
the Coalinga field, or about seven miles north of Coalinga.
As the basal beds of the Etchegoin are followed westward
through the field, they rest upon, and then close out succes-
sively lower and lower strata of the CoaHnga Beds until
finally the latter disappear from the stratigraphic section
entirely, and the Etchegoin Beds are found resting upon the
Monterey Shales. A similar occurrence may perhaps also
be seen west of CoaHnga, where the Etchegoin Beds are
found passing from the CoaHnga Beds to the underlying
Chico.

A faunal study of the CoaHnga Beds shows them more
closely related to the Temblor than to any later or living
faunas. Notice for example in the basal CoaHnga — that is
in the Reef Beds — the occurrence of Agasoma kernianum.
Area montereyana, and Pecten discus, besides many other
forms closely alHed to those of the Temblor Beds.

1 86 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

Other Occurrences of Lower Miocene within the

Interior Basin.

For purposes of comparison and for a more complete
understanding of the Lower Miocene fauna within the inte-
rior basin of California, brief descriptions of other occurrences
are here given. In a short paper recently published by Dr.
Merriam^ the Lower Miocene beds of Contra Costa County
are described, including a partial list of fossils. The beds are
said to rest directly upon the Tejon, and to be overlain by
beds of Monterey Shale. The most characteristic species
are :

Aj^asoma gravidum Gabb Chione mathewsoni Gabb

Dosinia matheivsoni Gabb Mytilus mathewsoni Gabb

The stratigraphic thickness of these beds was not given,
but it is probably commensurate with that of the Temblor
Sandstone.

San Emidio Sf.ction.

An instructive section of the rocks of the San Emidio
Canyon is to be found in Whitney's^ description. In refer-
ring to this illustration, however, it is necessary to remember
that Eocene rocks were classed by him as Cretaceous.

Overlying the Eocene beds are beds of Lower Miocene
age with a fauna similar to that already described for the
Temblor Beds.

The dip is toward the north at a high angle, and the strike
is conformable to that of the Eocene and later rocks. The
Monterey Shales are missing from this section, or if present
were not recognized. The beds may be traced westerly and
northwesterly toward the Carisa, toward McKittrick and
Temblor, and perhaps easterly toward the Tejon ranch.

Beds of the Carisa Ranch.

Near the Carisa ranch house, along the San Juan River,
San Luis Obispo County, an enormous thickness of Miocene

1 Bull. Dept. Geol. Univ. Calif, v. 3, pp. 377-381.

2 Geol. Surv. Calif. Geol. v. i, p. 189.

Geol.— Vol. II.] AXDERSON—STRATIGRAPHIC STUDY 187

rocks is exposed with a dip of 40° to 60*^ to the northeast.
The series consists of alternatincr horizons of sandstone and
siliceous shales, the former of which greatly preponderate.

The lowest fossil horizon near the base of the series, and
the second one some thirteen hundred feet above the base
contained ver}' nearly the same fauna, from the latter of
which the following species were collected :

Turritella ocoyaiia Conrad Cytherea {Callisia) mathewsoni

Trochita filosa Gabb Gabb

Agasoma gravidiim Gabb Dositiia mathewsoni Gabb

Crcpidula grandis Conrad Mytilns mathewsoni Gabb

Crepidida p7-aert(pta Conrad Lucina richthofeni Gabb

Neverita callosa Gabb Pec ten estrellatms Conrad

Fusus {Hemifusus) icilkesana n. sp. Pecten sp.

Scaphander jugulai-is Conrad Glycimeris estrettanus Conrad

A third fossiliferous horizon within twenty-five hundred
feet of the top of the Miocene series yielded essentiall}' the
same fauna with one or two additional forms, as Pecten
nevadensis, Oliva calif ornica n. sp., and an undescribed
species of Dosinia, etc. This horizon is well exposed about
four miles southeast of La Panza Springs on the east side of
the San Juan River. It is overlain by shaly beds with a
fauna resembling that of the Monterey Shales.

Kern River Beds.

Although this locality' was not specially studied, and lies
without the Mount Diablo Range, still it has long been
known, and lies within the interior basin of California.
The locality is on Kern River, two to six miles east of Oil
City, Kern County. The strata are mainly sands and sand}'
clan's, dipping gently toward the west. The entire thickness
of the strata exposed along the river aggregates about three
thousand feet, of which the lower two-thirds belongs to the
Miocene. Toward the base they become very fossiliferous,
containing numerous species of invertebrates, teeth of sharks,
and bones of fishes and other marine vertebrates.

The following species were collected in the vicinity of
Barber's ranch, chiefly north of the river:

[3] October 25, 1905

i88

CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

Agasoma gravidtini Gabb
Agasoma kernianum Cooper
Agasoma sinuahmi (?) Gabb
Conus otveniana n. sp.
Neverila callosa Gabb
Turritella ocoyana Conrad
Ctinia biplicosta Gabb
Oliva californicus n. sp.
Scaphander jugularis Conrad
Trophon kernensis n. sp.
Dentalium subsiriafiwi Conrad
Dentaliiiin sp.
Pleurotoma ( ClathureUa) dumbleana

n. sp.
Nassa arnoldi n. sp.
Trochita filosa Gabb
Crcpidula pracrupta Conrad
Purpura lima Martyn
Sigarctus scopulostis Conrad
Terebra cooperi n. sp.
Bullia {Molopophorus) anglona^ia

n. sp.
Cancellaria pacificus n. sp.
Cancellaria joaquinensis n. sp.
Cancellaria condoni n. sp.

Cancellaria simplex n. sp.
Cancellaria dalliana n. sp.
Cy there a ( Callista) niathezvsoni

Gabb
Vemis {JMercenaria) pertemiis

Gabb
Venus ( Chione) teniblorensis n. sp.
Dosinia ^nalhewsoyii Gabb
Dosinia sp.

Mactra {Spisula) /alcata Gould
Mactra sp.

Pachydesma inezana Conrad
Pecten discus Conrad
Solen sicarius Gould
Solen sp.

Tcl/ina ocoyana Conrad
Tellina sp.

Yoldia impressa Gabb
Lucina richthofeni Gabb
Area montcreyana Osinont
Corbicula dumbleana n. sp.
Leda oregona Shumard
Cytherea sp.
Hotnomya sp.
Pectunculus sp.

Many yet undescribed species occur in this collection, and
the locality is well worth a more exhaustive stud3\ On the
whole it probably better represents the Lower Miocene
fauna of the California interior than an}^ other locality
that has been described.

Correlations.

It is not at present possible to correlate with much accuracy
the Tertiary beds of the Mount Diablo Range with others
occurring in distant parts of the Coast or of the State.
For the Pliocene, and perhaps also the Miocene periods, a
number of minor provinces must be recognized along the
Pacific border, corresponding to the physical geography of
the time. North of the Klamath Mountains the Miocene
and Pliocene faunas are in a measure specifically different
from those of Central California, while these are in turn
somewhat unlike those of the southern coast of California.

Geol.— Vol. II.] ANDERSON— ST RATIGRAPHIC STUDY 1 89

The exact line of separation between the Cahfornian prov-
inces of the later Neocene appears to follow very nearly the
line of the outer Coast Ranges as far south as the head
waters of the Salinas Valley drainage, and follows in turn
the axis of the Santa Cruz and the Santa Lucia ranges,
turning eastward to Pine Mountain and the Tehachapi
Range at the latitude of Moro Bay. The Pliocene beds of
the coastal valleys south of the Santa Lucia Range are
faunally more closely related than any of them are with the
Pliocene of the interior valleys. The interior basin of the
Pliocene includes not only the Great Valley, but the Salinas
and Carisa valleys and other small valle3's of the Coast
Ranges, probably extending as far north as Lake and
Tehama counties.

Within these provincial limits a faunal and stratigraphic
correlation of Pliocene deposits, at least, is likely to be more
successful than are present attempts at a detailed correlation
of deposits within two or more provincial basins.

In the Salinas Valley occur late Tertiary beds that can be
satisfactorily compared and correlated with those of the
Mount Diablo Range. At Santa Margarita and on the
Nacimiento River, at La Panza Springs, and on the Estrella
and San Lorenzo rivers, are beds that are entirelv similar.
At Santa Margarita these beds have been mapped and
described by H. W. Fairbanks' as the Santa Margarita For-
mation.

It is quite likely that a correlation of the INIiocene beds,
or at least of some of them, will have to be restricted within
the same territorial limits. The Vaquero sandstones described
by Dr. H. W. Fairbanks as occurring within the drainage of
the Salinas River lack thus far any faunal description, and
his correlation of these with beds occurring south of the
Santa Lucia Range is not supported by any faunal evidence.
On the other hand the fauna occurring at the base of the
Miocene near San Luis Obispo is characteristic over the
whole extent of the coast border, especially south of that
point.

1 San Luis Folio, U. S. Geol. Surv. no. 101.

190 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

Conclusions.

The conclusions to be arrived at from the stratigraphic
study of this field are not at variance with, but are mainly
confirmatory of much that has been written during the last
decade. The Tertiary^ formations of California have thus far
been too little studied and analyzed, though for general scien-
tific as well as for economic reasons they richly deserve
attention. In the present contribution to the literature it is
believed that the following points are either made clear or are
at least clearly indicated :

1. Stratigraphic nonconformities exist in the Mount Dia-
blo Range between all of the chief periodic series, and in
some instances between different members of the same
series.

2. The Eocene strata are capable of being divided into
several distinct members, of which the Tejon portion contains,
at least locally, two sandy members separated by one of
shale.

3. The Neocene deposits of California can be separated
into two or more basins or minor provinces, those of the
Mount Diablo Range belonging to the California interior
basin and being characteristic of the same.

4. In the Mount Diablo Range two clear stratigraphic
nonconformities exist within the Neocene, dividing these
deposits into three groups, lower, middle, and upper. The
lower and older of these groups contains the well recognized
Miocene strata of Central California ; the later and younger
group, the strata which have been described as Etchegoin or
San Pablo, and which are believed to be of Pliocene age:
while the interv^ening or middle group, on account of its
faunal resemblance to the older Miocene, is more logically
classed in this period than in the period following.

5. In the older Miocene two distinct members are to be
recognized; viz., the Monterey Shale and the Temblor
Sandstone.

6. The most complete and therefore the most typical
fauna of the Lower Miocene of the California interior is that

Geol.— Vol. II.] AXDERSON—STRATIGRAPHIC STUDY I9I

of the Kern River Beds on the southeastern border of the
San Joaquin Valley.

7. The most complete and typical development of the
San Pablo strata is not found in the locality from which it
takes its name, but along the northeastern flanks of the Mount
Diablo Range, as in western Fresno County, where the series
attains more than four times the thickness stated in its original
description.

8. The Etchegoin series is capable of being subdivided,
at least locally, into two or more separate members, each of
which has a greater stratigraphic thickness than was origin-
ally given for the entire body of similar beds occurring on
San Pablo Bay, which are altogether embraced in the lower
division, the Etchegoin Sands.

9. The uppermost stratigraphic unit of the Mount Diablo
Range is one of fresh-water origin, and is perhaps equivalent
to the Orindan Formation of the Berkeley Hills, as described
bv Dr. Lawson.

10. The Neocene faunas of California are far from being
completely known ; thev offer a rich field for study, and it is
believed that such study would yield results of great value to
students of stratigraphic geology.

Descriptions of Species.

Amons: the manv fossils collected in the Mount Diablo
Range and the California interior during the field-study
represented in the foregoing paper, many new species have
been discovered, some of which are here described.

While undescribed forms have been obtained from both
Cretaceous and Tertiary strata, the latter only are illustrated
in the following pages. The list of new forms from each of
the Tertiarv horizons might be considerably extended b}^ the
use of fragmentary and imperfect materials, but the descrip-
tion of such material is not only unsatisfactory but results in
much harm to paleontologic science.

]Many of the California Tertiary invertebrates were origin-
ally described in literature that has become inaccessible, and

192 CALIFORNIA ACADEMY OF SCIENCES [Proc. 3D Ser.

some of the accessible literature contains only unsatisfactory
figures and descriptions; therefore it is highly desirable to
have re-descriptions and better drawings made when authen-
tic material can be obtained and properly identified. The
species figured and described by Conrad in the Pacific Rail-
road Reports can rarely be identified except from the type
localities, and then only by the utmost care and reservation ;
the same is often true of the species described by Gabb in
the Paleontology of California. Much of the confusion and
uncertainty in stratigraphic determination in the Pacific Coast
Tertiary originates in such faulty descriptions. Correct
specific determinations cannot be made from much of the
literature upon California paleontology that is accessible to
students of the subject, and until these can be made, trust-
worthy determinations of faunal horizons are likewise impos-
sible.

Where any departure has been made from the current
paleontological nomenclature it has been with deference to
the classification proposed by Zittel in his Handbuch der
Palceontologie, and it must be confessed that such a standard
should have been adopted throughout. An attempt to do
this would, however, involve a considerable amount of work
in revising the Pacific Coast nomenclature, and that is beyond
the purpose of this paper.

The paleontological materials that form the basis of this
study have been largely collected by the writer ; they have
become the property of the California Academy of Sciences,
and are a part of its permanent collections.

FORAMINIFERA.

Eocene.

Plate XIII, Figs. 9-29.

For the purpose of calling attention to the many well pre-
served forms of Foraminifera in the Eocene rocks of the
Mount Diablo Range, and to illustrate some of the more
common genera, a few have been figured without any attempt

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY I93

at specific identification, along with other Eocene species
occurring in very nearly the same horizon. These Foramin-
ifera are as follows:

Nodosaria Cyclammina

Lagena (?) Pulvulina

Sagrina Polymorphina (?)
Vagittnlina

Some of the species of Foraminifera are very large, and
can be easily seen with the unaided eye. Some species of
Nodosaria attain a length of three-fourths of an inch, and all
of them are easily distinguished with a good lens. Most of
the forms are found in calcareous concretionary masses,
occurring as lenses in the argillaceous beds described in
this paper as the Kreyenhagen Shales.

ECHINODERMATA.

Eocene and Miocene.
Scutella sp. A. n. sp.

Plate XIII, Fig. 8.

Test small, thin, disk-like, oval or sub-pentagonal; anal pore supermar-
ginal; apical star symmetrical, but not central; calyx open.

The numerous specimens of this species which were found,
are immature and cannot yet be satisfactorily described.
Most of them are laterally convex and small.

Occurrence. — The species is not rare in the Avenal Sands
west of Coalmga.

Astrodapsis merriami n. sp.

Plate XIV, Figs. 33 and 34.

Disk small, circular, depressed; margin only slightly notched at the
ambulacral extremities; apex central, only slightly elevated, star symmet-
rical, petals equal but not reaching the margin of the disk, and slightly
elevated; anal pore marginal; ambulacral furrows of inferior surface straigiit
and simple. The largest specimens have a diameter of i)^ inches, though

194 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

the usual size is }^ of an incli. The disk is thin and flattened but shows a
decided tendency to form elevated stars on the upper surface.

Occurrence. — This form is extremely abundant locally in
the Temblor Beds of the Mount Diablo Range, at Tar
Springs, Kreyenhagen's, and Temblor.

Cassidulus californicus n. sp.
Plate XIII, Figs. 6 and 7.

Test small, elliptical, robust and often somewhat globular; lower surface
flattened, or concave, upper surface convex; mouth not central, round, and
occupying a position ^-^ of the distance from the anal margin; anal pore ter-
minal; apical star nearly symmetrical, central on dorsal surface; tubercula-
tion distinct, the tubercules lying within rounded pits. There is a tendency
to form shoulder-like expansions on the periphery behind the position of the
mouth.

Ocairrence. — This species is not rare in the Avenal Sands
west of Coalinga.

LAMELLIBRANCHIATA.

Eocene.

Spondylus carlosensis n. sp.

Plate XIII, Fig. i.

Shell of medium size, sub-circular or obliquely ovate, radially ribbed,
convex; costae granulated or obscurely spinose; ears and hinge rather
broad. The costae radiate in graceful, sinuous lines from the beak to the
margins, and occur in pairs or triplets, every second or third rib being inore
elevated than the others.

Occurrence. — This species occurs only rarely in the Avenal
Sands west and north of Coalintja.

Ostrea aviculiformis n. sp.

Plate XIII, Figs. 3-5.

Shell small, very inequivalve, quadrate, oblique, laminated; inferior
valve convex and strongly arched; superior valve thin, often concave, and
sharply laminated in thin concentric folds; hinge broad and somewhat

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY I95

straight. The surface of the convex valve is marked only by concentric
lines of growth. The margin is more or less ragged or irregular.

This species bears some resemblance to Ostrea sellaeforniis
Conrad, from the Eocene of Alabama.

Occurrence. — This species is found only occasionally in the
Avenal Sands west and north of Coalinga.

Miocene.
Cyrena (Corbicula) dumblei n. sp.

Plate XIV, Figs. 30-32.

Shell moderate in size, or large, 3 inches in greater diameter; sub-circular
in outline; beaks central, not greatly elevated, incurved; surface marked by
heavy and irregular concentric ridges, or smooth in young shells; teeth sharp
and prominent; lateral tooth long and slightly curved and finely crenulated.

This species differs from C. californica Gabb in being
larger and more circular in outline and in having generally a
more robust form.

Ocairrence. — This species is not rare in the lower Miocene
beds of Kern River.

Venus (Chione) pertenuis Gabb.

Venus pertenuis Gabb, Pal. Calif, v. 2, pp. 22 and 55, pi. v, fig. 37.

In Gabb's description of this species there is some doubt
expressed as to its proper sub-generic determination, though
he says it very probably may prove to be a Chione. Several
specimens have been obtained from the Lower Miocene beds
of Kern River, some of them showing the hinge from which
Gabb's judgment is readily confirmed.

Venus (Chione) conradiana n. sp.

Plate XIV, Fig. 35.

Shell large, rather thick, cordate, broadly rounded below, and much
produced behind; beak prominent, anterior, incurved; lunule large; surface
marked by concentric ridges, strongest in the umbonal region; margin thin
and not crenulated.

196 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

This shell is related to Chiofie pertemtis Gabb, but has not
the triangular outline of that species, is more produced pos-
teriorily, and less produced before. The hinge is fairly well
exposed showing its generic features unmistakably.

Occurrence. — This species occurs with C. per tennis in the
Lower Miocene beds three miles east of La Panza Springs,
San Luis Obispo County.

Venus (Chione) temblorensis n. sp.

Plate XIV, Figs. 36-38.

Shell moderate in size, 2% inches in larger diameter, i>^ inches thick;
sub-triangular in outline; beaks slightly anterior; incurved; lower margin
rounded, crenulated within, produced to an angle posteriorly; hinge margin
straight; surface ornamented with concentric ridges and radiating ribs. The
concentric ridges rise in gently fluted and ruffled folds. The radiating ribs
occur singly from beak to margin.

This species is undoubtedly related to C. guidia Brod. &
Sow. but is ornamented with single instead of double ribs or
riblets, less prominent concentric folds, and generally differ-
ent outline. It is perhaps ancestral to the latter species.

Occurrence. — Lower Miocene beds of Kern River and
Temblor.

Cylherea (Callista) diabloensis n. sp.
Plate XVII, Figs. 83-85.

Shell large, thick, obliquely cordate in outline; beaks prominent, anterior,
incurved; margin broadly rounded below, produced in front; cardinal
region widely excavated; lunule large, impressed; surface ornamented by
smooth concentric ridges, more or less interrupted as in C. callosa Conrad;
inner margins not crenulated.

This species resembles specimens of C. callosa from the
California coast, but is shorter and has a greater lateral
thickness. Moreover it does not show the internal thicken-
ing of the valves as in C. callosa.

Occurrence. — This species is not uncommon in the Coalinga
Beds west of Coalinga, Fresno County.

Geol.— Vol. II.] ANDERSON— ST RATIGRAPHIC STUDY 197

Pectunculus septentrionalis Middendorf.

Plate XVII, Figs. S6 and 87.

Pcciunculus septentrionalis (Midd.) Carpenter, Brit. Assn. Rept. 1856,

p. 219.
Glycymeris septentrionalis (Midd.) Arnold, Mem. Calif. Acad. Sci. v. 3,

p. loi, pi. XVIII, fig. 10.

This species is well described by Arnold, though the
sculpture of the shell is not shown in his figure. It will be
noticed upon a comparison of the figures that the form from
San Pedro has a smaller ligamental area and a somewhat
higher beak than the form here represented.

Occurrence. — This species is abundant in the Etchegoin
Beds both north and south of Coalinga, and is identical with
or closely related to a similar species occurring in the San
Pablo Beds on San Pablo Bay, Contra Costa County.

Diplodonta harfordi n. sp.

Plate XVII, Figs. 88 and 89.

Shell not large, rotund, sub-quadrate in outline; beaks nearly central, low,
closely approaching each other; cardinal margin straight, excavated; anterior
margin sometimes a little produced, but generally rounded; surface marked
only by concentric lines.

This shell is allied to D. orbella Gould, but has a less
prominent beak and a straight hinge margin.

Occurrence. — This shell occurs abundantly in the Coalinga
Beds west of Coalinjra.

Pecten coalingaensis Arnold.

Plate XVIII, Figs. 94-98.

Pecten {Pecten) coalingaensis Arnold.

Shell moderate in size, the largest having a diameter of ^}i inches;
inequivalve, radially ribbed; lower valve convex, upper concave.

Arnold's description of this species is not yet published,
but as the specimens here figured are from his type locality
and have been identified by Dr. Arnold, there is no doubt

198 CALIFORNIA ACADEMY OF SCIENCES [Proc. 3D Ser.

about the correctness of the determination. They have
been referred by Arnold to the Miocene of the Kreyenhagen
ranch, but the true horizon is that of the Etchegoin Beds,
which are probabh' Pliocene.

Ocairreuce. — This species is common in the Etchegoin
Beds of the Mount Diablo Range, at the Kreyenhagen
ranch on Zapata Chino Creek.

Pecten wattsi Arnold.

Pecten ivattsi Arnold, Tert. and Recent Pectens of Calif., Profess. Paper
no. — , U. S. Geol. Siirv. .

Ocairreuce, — This species occurs with the preceding.

Pecten etchegoini n. sp.

Plate XVIII, Figs. 92 and 93.

.Shell rather large, thick, and ovate in outline; ears nearly equal, costate;
ribs strong and grouj^ed in sets of 3 or 4, forming radial undulations in the
shell, seen both within and without; margin of valve fluted within. The
grouping of the ribs is a variable feature of the shell. In some specimens
the depressions are wider, in others narrower than in the one figured. Con-
centric lines are usually visible on the shell.

Occurrence. — The species occurs with the two preceding
in the Etchegoin Beds of the Kreyenhagen ranch on Zapata
Chino Creek.

GASTEROPODA.

Eocene.

Cypraea fresnoensis n. sp.

Plate XIII, Fig. 2.

Shell of medium size, i>^ inches long, i inch in diameter, robust or sub-
globose; spire covered; canal produced a little in front. The epidermis
covers the spire in adult age, though in the figured specimen it has been
removed. The aperture is narrow and curved. The dentition is not shown.

Occurrence. — This species is rare in the Avenal Sands
northwest of Coalinga, western Fresno County.

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY 199

Miocene.
Cancellaria dalliana n. sp.

Pl.\te XV, Figs. 39-42.

Shell of moderate size, fusiform; spire high and angular; whorls angular
and spinose; columella thickly crusted within in old specimens; surface
marked with strong varical ridges and lines, the ridges rising in thin edges
on the upper surface of the body whorl. The lower part of the body
whorl is ornamented with strong revolving lines with wide interspaces in
which there are usually 1-3 secondary lines. The canal notch is not shown.

Occurrence. — This species occurs with the succeeding in
the Lower Miocene beds of Barker's ranch, on Kern River.

Cancellaria pacifica n. sp.

Plate XV, Figs. 43-45.

Shell moderate in size, %-\yz inches in length, width Yz as great; spire
moderately elevated; mouth oval in outline; whorls angulated, bearing
small nodes on the upper angles; surface ornamented with revolving lines,
heavier and lighter lines occurring alternately on the body whorl, crossed by
vertical ridges.

This shell seems to be somewhat closely related to
C. granosa Sowerby, described from Van Dieman's Land.

Occ2irreiice, — This shell occurs with the preceding species
in the Lower Miocene beds of Kern River.

Cancellaria joaquinensis n. sp.

Plate X\^ Figs. 46-48.

Shell of moderate size, stout, and ovate; i inch or more in length and
nearly as broad; spire medium or low, sloping evenly without conspicuous
angles; shell thick; inner lip crusted; surface ornamented chiefly by revolv-
ing lines and interspaces, with finer secondary lines within; varical ridges
weak, but forming on the upper angle of the body whorl a single circle of
nodes.

This species is related only distantly to any other described
form occurring on the Pacitic Coast.

Occurrence. — Lower Miocene beds of Kern River, where
four or more well preserved specimens were obtained.

200 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

Cancellaria condoni n. sp.

Plate XV, Figs. 49 and 50.

Shell of moderate size, i-i>4 inches in length, }4-}^ inch wide; spire
high; whorls angular, slightly sloping above; surface ornamented with strong
revolving lines, with wide interspaces, crossed by strong varical ridges form-
ing tubercular nodes on the upper angle of the whorls; inner lip crusted,
bearing 2 spiral folds on the columella.

This species is apparently related to the C. oregoiie?tsis
Conrad described from the Astoria beds of Oregon.

Ocairrence. — This species is represented by four speci-
mens from the Lower Miocene beds of Kern River.

Cancellaria simplex n. sp.

Plate XV, Figs. 51 and 52.

Shell moderate in size, simple and inconspicuously marked, resembling
C. pacifica, but having a less elevated spire, and generally shorter whorls.
The spiral lines and longitudinal ridges are both more reduced and the
width of the shell is greater. The inner lip is well crusted. The length of
the largest shell found is nearly 2 inches.

Ocairrence. — Lower Miocene beds of Kern River, with

the precedin

Cancellaria vespertina n. sp.

Pl-^vte XVI, Figs. 77 and 78.

Shell not large, fusiform, angulated, bearing tubercules, longitudinally
ribbed; spire elevated, but not high; whorls slightly sloping above; aperture
ovate, inner lip crusted; canal short; surface ornamented more conspicuously
with vertical ridges, crossed by faint spiral lines, seen more plainly on the
lower portion of last whorl.

The species resembles somewhat C. iirceolata Hds. but is
less robust, with a higher spire and less prominent spiral
ridges on the columella, besides having strong tubercules on
the angles of the whorls.

Occurrence. — The species is not abundant, but occurs in the
Coalinga Beds west of Coalinga, Mount Diablo Range.

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY 20I

Scaphander jugularis Conrad,

Pl.^te XV, Figs. 56 and 57.

Bu/la jugularis Conrad, Pac. R. R. Rept. v. 5, p. 328, pi. vii, figs. 62
a and b.

Shell not large, i-i>^ inches in length, width i^ as great; contracted
toward the posterior end; aperture wide, ovate; inner lip crusted; whorl
loosely convolute, narrowing behind; surface ornamented by revolving lines
crossed by oblique lines of growth. The revolving lines consist of flattened
ridges and rounded grooves of equal width.

Conrad's figure lacks sufficient description to make abso-
lute identification possible, but as the localities are contiguous
and the horizon practically the same, there can be little doubt
as to identity.

Occurrence. — Lower Miocene beds on Kern River, a few
miles south of Ocoya Creek.

Oliva calif ornica n. sp.

Plate XV, Figs. 54 and 55.

Shell moderate in size, i-i>^ inches long, width more than half as great,
ovate, narrowing below; spire low and rounded; aperture narrow, inner lip
somewhat crusted; columella bearing 2 principal spiral plications, with finer
lines both above and below; suture impressed and sharply defined on
adolescent and mature shells; surface marked only by lines of growth.

Occurrence. — Lower Miocene beds of Kern River, Barker's
ranch, etc,

Oliva futheyana n. sp.

Plate XV, Fig. 53.

Shell similar in many respects to the preceding, but narrower, and having
a more elevated spire, and more graceful outline.

Occurrence. — This shell occurs with the preceding.

Conus oweniana n. sp.

Plate XV, Figs. 58 and 59.

Shell small, conical; spire moderate, conical; whorls flattened, or concave
above; suture impressed on young shells; aperture narrow, and straight;
surface marked by distant, fine revolving lines.

202 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

This species is unlike C. califoruica Gabb in having a
lower and less rounded spire, a less ovate outline, and a
narrow straight aperture.

Occurrence. — This shell occurs in the Lower Miocene beds
of Kern River.

Purpura lima Martyn.

Plate XV, Figs. 62 and 63.

Purptira lima Martyn, Conch, fig. 47.

Purpura lima (Mart.) Tryon, Man. Conch, v. 2, p. 175, pi. liii, figs. 156,
158, 159, and 161.

Among the many moUuscan species originally described
in obscure or inaccessible literature is the above. Authentic
samples of this shell are in the collections of the California
Academy of Sciences, and the identitication of the fossil
species is from a comparison with these. The fossil speci-
mens are a little shorter, with a less elevated spire, but the
difference seems to be insignificant.

Ocairrence. — The four or five samples of this species that
have been found fossil are from the Lower Miocene beds of
Kern River.

Trophon kernensis n, sp.

Plate XVI, Figs. 64 and 65.

Shell rather large, length from 2-3 inches, width ij4 inches; graceful in
outline, narrowing rapidly before; spire rather short, conical, and angular,
but sloping above, bearing tubercules, or very short spines on the angles,
more prominent on very young shells; surface ornamented chiefly by lines
of growth, but bearing faint spiral lines on the lower part of the whorl,
noticeable especially in young shells; aperture pear-shaped, and narrowing
to a long canal; inner lip crusted; canal long and narrow.

This species is only distantly related to T. ponderosum
Gabb, but more nearly related forms are found in the Pliocene
of California.

Occurrence. — This shell is from the Lower Miocene beds
of Kern River.

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY 203

Trophon gabbiana n. sp.

Plate XVI, Figs. 79 and So.

Shell not large, laminate, spinose on the angles; canal short, recurved;
spire high, sloping above; body whorl tapering below. The mouth narrows
regularly toward the canal. The spines are often considerably suppressed
on the angles, and on the lower part of the last whorl there are numerous
spiral lines.

The shell differs from T. ponderoswn Gabb in having a
recui-\^ed columella, spiral lines below, and less prominent
spines.

Ocaun^ence. — This shell occurs in the Coalinga Beds of the
Mount Diablo Range, nine miles north of Coalinga.

Terebra cooperi n. sp.

Plate XVI, Figs. 66 and 67.

Shell of moderate size, tapering regularly; length i>^-2 inches, width of
body whorl >^ inch or less; aperture narrow and elongated, with simple
outer lip; surface ornamented with slightly sinuous vertical ribs or lines
closely set on the whorls; inner lip only slightly crusted; columella with a
narrow oblique fold on the outer side; the upper Y^ of the whorls bearing a
constricted band, not clearly shown in the figures.

This species is undoubtedly related to Terebra wattsiana
Cooper,^ but is characterized by two or more distinguishing
marks, the depressed zone on the upper part of the whorls
and the narrow fold on the columella. A similar species
is found in the late Pliocene beds of San Diego, California.

Occurrence. — This species is found in the Lower Miocene
beds of Kern River, but it is not abundant.

Sigaretus scopulosus Conrad.
Plate XVI, Figs. 72 and 73.

Sigaretus scopulosus Conrad, U. S. E.xpl. Exped. (Wilkes) pi. xix, figs. 6

and 6a/ text p. 727.
Sinuni scopulosuui Conrad (Gabb), Pal. Calif, v. 2, p. 114, etc.

Shell moderate in size, obliquely oval, slightly flattened above, hollowed
below; surface marked with revolving lines, equal in width with the inter-

1 Bull. no. 4, Calif. State Min. Bur. 1894, p. 39.

[4] October 25, 1905

204 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

spaces, and flattened above; spire very small, but with distinct suture; spiral
lines not showing within.

Three specimens in the collections of the California Acad-
emy of Sciences are apparently referable to this northern
species, and this determination is supported by other evi-
dence and faunal resemblances.

The species has a near relative in the Pliocene of San
Fernando as seen in 6". planicostnni Gabb, but the form of
the shell is evidently different.

Occurrence. — Lower Miocene beds of Kern River.

Nassa arnoldi n. sp.

Plate XVI, Figs. 70 and 71.

Shell small, acutely ovate; spire moderately elevated, bearing 5 whorls;
aperture circular, outer lip always bordered by a thickened varex; columella
short, bearing only a slight, or no sulcus; surface ornamented by spiral and
longitudinal ridges forming a reticulation as in the young of N. perpengtiis
Hds.

This species differs from N . perpengnis in its smaller size,
more regular and symmetrical form, shorter columella, the
absent, or much reduced sulcus, and the bucal border which
appears on all of the specimens that have been found.

Occurrence. — This species occurs with the preceding in
the Lower Miocene beds of Kern River.

Crepidula praerupta Conrad.

Plate XVI, Figs. 68 and 69.

C. praerupta Conrad, U. S. Expl. Exped. (Wilkes) pi. xix, figs. 9, 9a, loa,
\ob; text p. 727.

Shell of medium size, i-i>^ inches long; strongly curved; aperture
elliptical, or ovate; surface marked by irregular lines of growth.

Occurrence. — The species is found abundantly in the Lower

Miocene beds of Kern River.

Pleurotoma (Clathurella) dumblei n. sp.

Plate XV, Figs. 60 and 61.

Shell small or medium in size, i-ij^ inches long; spire high; whorls 6 or
more, convex; aperture simple, ovate, inner lip uncalloused; canal very

Geol.— Vol. II.] ANDERSON— STRATIGRAPHIC STUDY 205

short; surface ornamented by strong spiral and longitudinal lines, giving a
cancellated sculpture.

Occurrence. — This species occurs abundantly in the Lower
Miocene beds of Kern River,

Bullia (Molopophorus) anglonana n. sp.

Plate XVI, Figs. 74-76.

Shell moderate in size, i inch in length, % inch in width; spire moderately
elevated; aperture broad, lip simple, notched above; columella crusted,
whorls angulated, bearing tubercular, or spinose nodes above, and on lower
part of body whorl; surface ornamented with lines of growth, and with
revolving lines, strongest on the lower portion of the body whorl. The
anterior notch is deep, and bordered by 2 strong folds which extend upward,
revolving obliquely around the columella, forming a wide canal, shown
only in figure 74.

This species is somewhat related to B. striata Gabb, from
the Tejon Beds, but more nearly related to undescribed
species occurring in the so-called Oligocene Beds of Oregon.

Occurrence. — This species occurs not rarely in the Lower
Miocene beds of Kern River.

Fusus (Hemifusus) wilkesana n. sp.

Plate XVI, Figs. 81 anu 82.

Shell moderate in size, robust, tapering rapidly below; spire moderately
elevated, angulated, with tubercular nodes on the angles of the whorls; sur-
face strongly marked by spiral lines and longitudinal ridges, especially
prominent at and below the angles of the whorls; canal only moderately
prolonged; open; columella somewhat curved.

This species seems to be related to, and is possibly iden-
tical with Fiisus corpiilentus Conrad, from the Miocene beds
of Astoria, Oregon; but as Conrad's figure was drawn from
a cast, it is not possible to establish its identity with the
species described here.

Occurrence. — The Lower Miocene beds (Temblor Beds)
at the Kreyenhagen oil wells. Kings County.

2o6 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

Chorus carisa'ensis n. sp.

Plate XVII, Figs. 90 and 91.

Shell rather large and thick, strongly spinose, and oblique; spire moder-
ately high, sloping above; body whorl narrowing rapidly below; aperture
large, triangular, bearing a stout tooth on the outer lip near the upper end
of the canal; canal narrow, short, and strongly recurved; columella crusted
and strongly recurved; surface marked only by strong lines of growth.
There are about 8 strong spines on the angles of each whorl, excavated in
front and conve-x behind.

Occurrence. — This shell is common, though not plentiful in
the lower Etchegoin Beds of the Mount Diablo Range, near
La Panza Springs, San Luis Obispo County.

California Academy of Sciences,
July 31, 1905.

208 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

EXPLANATION OF PLATE XIIL

foraminifera.

Page

nodosaria 193

Figs. 9-15.

Lagena (?) 193

Fig. 16.

Sagrina i^:^

Figs. 17-18. ,♦ .

Vaginulina 193

Fig. 19-

CVCLAMMINA 193

Figs. 20-22.

PULVUUNA 193

Fig. 23.

POLYMORPHINA (?) 193

Figs. 24-29.

Echinodermata.

Cassidulus californicus n. sp. I94

Figs. 6-7.
Scutella sp. A. n. sp. i93

Fig. 8.

MOLLUSCA.

Spondylus carlosensis n. sp. I94

Fig. I.
Ostrea avicidijormis n. sp. I94

Figs. 3-5-
Cypraea fres7ioensis n. sp. 198

Fie. 2.

FHDC.CAUACAD.SCI.a^ Seh. Gedl Vdl.II.

[Aniiersdn] Vlkte nil.

20 21

29 28

JWAffr VfELLMAM. VEL

Bmmi.-iziH.HHrrTaN s sey. bt;

2IO CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

EXPLANATION OF PLATE XIV.

Page
Cyrena {Corbiaila) duinblein. sp. 195

Figs. 30-32.
Astrodapsis nierriami n. sp. 193

Figs- 33-34.
Venus {Chiofie) couradiatia n. sp. 195

Fig- 35.
Venus {C/iione) temblorensis n. sp. 196

Figs. 36-38.

FHnc.CAL.AcAi]^ Sci 3° See. GedlVdl.1I.

AnderbqnI Plate XIV

XARr VfELUt/W. HEL

™CTn .-IjrH.±W 11 1 OK SHEY. GT.

212 CALIFORNIA ACADEMY OF SCIENCES TPkoc. jd Ser.

EXPLANATION OF PLATE XV.

Page
Cancellaria dalliana n. sp. 199

Figs. 39-42.
Cancellaria pacifica n. sp. 199

Figs. 43-45-
Cancellaria joaqiiinensis n. sp. 199

Figs. 46-48.
Cancellaria condoni n. sp. 200

Figs. 49-50-
Cancellaria simplex n. sp. 200

Figs. 51-52.
Oliva fiUheyana n. sp. 201

Fig. 53-
Oliva calif ornica n. sp. 201

Figs. 54-55-
Scaphander jttgularis Conrad 201

Figs. 56-57.
Conns oweniana n. sp. 201

Figs. 58-59-
Pleurotoma {Clalhurella) dumbleiw. sp. 204

Figs. 60-61.
Purpura lima Martyn. 202

Figs. 62-63.

PHDC.CALACAn.SCI.3° 5EH.GEDLVnL.II.

[Anders dn] Viate XV.

u \ * V\vA

<£?Sfe

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^^ =m

^Wm

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50 {y^

63 W^C^j'

JW/ir WELLMA/i, HEL.

■pBDTn.-lIIH.BHITTON «: HEY. BJ".

214

CALIFORNIA ACADEMY OF SCIENCES [Proc. 3D Ser.

EXPLANATION OF PLATE XVL

Page
Trophon kernensis n. sp. 202

Figs. 64-65.
Trophon gabbiana n. sp. 203

Figs. 79-80.
Terebra cooper i n. sp. 203

Figs. 66-67.
Sigareius scopulosus Conrad. 203

Figs. 72-73.
Nassa arnoldi n. sp. 204

Figs. 70-71.
Crepidiila praeriipta Conrad. 204

F"igs. 68-69.
Bullia {Molopophoriis) anglonana n. sp. 205

Figs. 74-76-
Cancellaria vespertina n. sp. 200

Figs- 77-78-
Fusus {Heniifusus) wilkesana n. sp. 205

Figs. S1-S2.

FRnc.CAL.ACAD.Bci. 3^ 5er.GedlVdl.II.

[Anders dn] Plate XVI.

iffiWr WELLMAN. DEL

■pHaio.-iim.BHrrraK * hey. b.t

2l6 CALIFORNIA ACADEMY OF SCIENCES [Proc. 3D Ser.

EXPLANATION OF PLATE XVIL

Page
Cytherea {Callisia) diablo'ensis n. sp. 196

Figs. 83-85.
Pectuiicuhis septcntrionalis Miudknuorf. 197

Figs. 86-S7.
Diplodoiita harfordi 11. sp. 197

Figs. 88-89.
Chorus carisaensis n. sp. 206

Figs. 90-91.

PRDC.CALACAE.SCI 3^ SEEGEDLVbLJI.

[Anderbdn] PIATE XVll.

■iM'

XfJSr wmjMAH. DEL

. H oHlilUN «r HEY. BT

2l8 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser

EXPLANATION OF PLATE XVIH.

Page
Pec ten etchegoini n. sp. 198

Figs. 92-93-
Pecten coalingaensis Arnold. i97

Figs. 94-98.

FHnc.CAL.ACAD 5ci.3^ Ser. GedlVql.IL

[ANnERSDN] Plate J^flll

^. \

iv«r wellman.hel.

fflDio.-iim.BHrrToii »hey. et.

220 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

EXPLANATION OF PLATE XLX.

View near Stone Canyon, showing Franciscan rocks and topography;
radiolarian jaspers in the foreground.

222 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

EXPLANATION OF PLATE XX.

View showing hard siliceous Franciscan rocks in an area of serpentine;
Mount Carlos.

2 24 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

EXPLANATION OF PLATE XXL

View showing eruptive rocks (basalt ?) within an area of Franciscan; Lewis
Creek, Monterey County.

^— wir^p-ip-^^^jpii

226 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

EXPLANATION OF PLATE XXIL

View showing stratigraphic series near New Idria; Cretaceous strata on
left and right, Eocene in middle distance, Neocene in the distance.

228 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

EXPLANATION OF PLATE XXIIL

V'lQw on Warthan Creek; Franciscan rocks in the foreground, Cretaceous in
the distance, Monterey Shales on the left.

230 CALIFORNIA ACADEMY OF SCIEXCES [Proc. 30 Ser.

EXPLANATION OF PLATE XXIV.
View on Los Gatos Creek, showing upturned Cretaceous strata.

'• • T

;* *

^ w.»

232 CALIFORNIA ACADEMY OF SCIENCES [Proc. 3D Ser.

EXPLANATION OF PLATE XXV.

View five miles north of Temblor, showing massive Eocene rocks in fore-
ground, overlain unconformably by Temblor Beds.

□

LD
R ■

I — r

r_J

□

234 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Seb.

EXPLANATION OF PLATE XXVL

View four miles north of Temblor, showing unconformity between Temblor
Beds and the underlying Eocene, dipping in opposite directions.

□

R ■

I — I

LJ
□

236 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

EXPLANATION OF PLATE XXVIL

View on north side of Antelope Valley, showing weathering of Eocene
sandstone.

238 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

EXPLANATION OF PLATE XXYIIL

View south of Warthan Creek, at summit of range, showing Temblor Beds
dipping northerly; F"ranciscan rocks on extreme left.

240 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Seb.

EXPLANATION OF PLATE XXIX.

View on summit of range south of Warthan Creek, showing Temblor Beds
dipping south, overlain by Monterey Shales, seen on the left.

242 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

EXPLANATION OF PLATE XXX.

View on south side of Warthan Creek, showing Monterey Shales dipping
northerly; PVanciscan rocks in the foreground and to the left.

244 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

EXPLANATION OF PLATE XXXL

View eight miles north of Coalinga, showing Monterey Sliales, Coalinga
Beds, and Etchegoin Beds successively, from right to left.

□
en

E
u
n

w4
□

n
) — I

246 CALIFORNIA ACADEMY OF SCIENCES [Proc. 3D Ser.

EXPLANATION OF PLATE XXXII,

View eight miles north of Coalin'ga, showing Etchegoin Beds dipping
southerly.

248 CALIFORNIA ACADEMY OF SCIENCES [Proc. 30 Ser.

EXPLANATION OF PLATK XXXIII.

View eight miles north of Coalinga, showing disturbance of Coalinga Beds
overlying Monterey Shales; Reef Bed seen at center, extreme right,
and extreme left, above.

□
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tr

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PRnC.CAL.ACAD.SCI.3^ SER.GEDLyDL.III.

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Cretaceous

foce//e

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Cretaceous

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[Anderson] Rate XXXIV

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Miocene

F/iocene (£tchegocn)

•a/ins& , /y-es/70 County, Ca/ifor/fia .

PROCEEDINGS OF THE ACADEINIY

(Octavo)
Third Series

GEOLOGY
Vol. I

No. I — The Geology of Santa Catalina Island. By William Sidney

Tangier Smith .-. % .50

No. 2 — The Submerged Valleys of the Coast of California, U. S. A.,

and of Lower California, Mexico. By George Davidson... .50
No. 3 — The Development of Glyphioceras and the Phylogeny of the

Glyphioceratidje. By James Perrin Smith 35

No. 4 — The Development of Lytoceras and Phylloceras. By James

Perrin Smith 35

No. 5 — The Tertiary Sea-Urchins of Middle California. By John \

C. Merriam f

No. 6 — The Fauna of tlie Sooke Beds of Vancouver Island. By i

John C. Merriam '

No. 7 — The Development and Phylogeny of Placenticeras. By James

Perrin Smith 50

No. 8 — Foraminifera from the Tertiary of California. By Frederick

Chapman 25

No. 9 — The Pleistocene Geology of the South Central Sierra Nevada

v.,'ith Especial Reference to the Origin of Yosemite Valley.

By Henry Ward Turner 50

No. 10 — The Comparative Stratigraphy of the Marine Trias of West-
ern America. By James Perrin Smith i.oo

Vol. II

No. I — Cretaceous Deposits of the Pacific Coast. By Frank I\I.

Anderson fi-75

No. 2 — A Stratigraphic Study in the Mount Diablo Range of Cali-
fornia. By Frank M. Anderson 1.25

INDEX TO VOLUME II, THIRD SERIES, GEOLOGY.
See page 130 for index to the Cretaceous Deposits of the Pacific Coast.

New names in heavy-faced type; Synonyms in italics.

Agasoma gravidum, 172, 183, 186, 187,
188

kemianum, 176, 185, 188

sinuatum, 188
Amauropsis alveata, 164, 166
Ammonites (Hoplites), 161
Amnicola turbiniformis, 182
Ancellaria elongata, 164
Anodonta decurtata, 182

nuttaliana, 182
Area (Barbatia) morsei, 166

montereyana, 172, 176, 185, 188

trilineata, 179, ISO
Architectonica horni, 164

specie?, 161
Astrodapsis

merriami, 171, 172, 193

tumidus, 176, ISO, 181

species, 177, 183
Baculites chicoensis, 161

species, 161
Ballanus, species, 170, 171, 172, 180
Belemnites, 161
Bulla jugularis, 201
Bullia (Molopophorus) anglonana, 188,

205
Bullia striata, 205
Callista, species, 173
Cancellaria condoni, 188, 200

dalliana, 188, 199

granosa, 199

joaquinensis, ISS, 199

oregonensis, 200

pacifica, 199

simplex, 188, 200

urceolata, 200

vespertina, 177, 200

species, 176
Cardita, 165
Cardita horni, 164, 166

species, 164, 166
Cardium cooperi, 164, 166

meekianum, 179, 180
Carinifex newberrvi, 182
Cassidulus califomicus, 166, 193
Chama, species, 180
Chione, 176

guidia, 196

mathewsoni. 170, 186
Chorus carisaensis, 206
Chrysodomus recurva, 177

species, 180

Cinulia obliqua, 161

Clypeaster (Scutella) breweriana, 180

Conus californica, 202

oweniana, 187, 201
Corbula paralis, 164
Crepidula excavata, 177

grandis, 187

praerupta, 171, 187, 188
Cuma biplicosta, 188
Cyclammina, 193
Cypraca fresnoensis, 198
Cyrena (Corbicuba) dumblei, 188, 195

californica, 177
Oytherea (Callista), species, 176, 177
Cytherea callosa, 196

diabloensis, 177, 196

mathewsoni, 187, 188

species, 188
Dentalium cooperi, 164

substriatum, 188

species, 188
Desmoceras, 161

hoffmanni, 161
Diplodonta harfordi, 175, 176, 177, 180
197

orbella, 197
Discohelix, 165

Dosinia mathewsoni, 170, 171, 186, 187,
188

ponderosa, 176, 177

species, 166, 187, 188
Echinodermata, 193-4
Ellipsosmilia granulifera, 166
Foraminifera, 192-3

Fusus (Hemifusus) wilkesana, 1S7, 205
Fusus corpulentus, 205

diaboli, 164

martinez, 164, 166
Galcms excentricus, 166

species, 177
Gari texta, 166
Gasteropoda, 198-206
Glycimeris estrellanus, 187

septentrionalis, 197
Goniobasis occata, 182
Gyrodes, species, 161
Hemifusus wilkesana, 172, 205

species, 176
Hinnites, species, 180
Homomya, species, 188
Inoceramus, 161

whitneyi, 161

[249]

250

CALIFORNIA ACADEMY OF SCIENCES [Proc. 3d Ser.

Lagena (?), 193
Lamellibranchiata, 194-8
Lamna clavata, 177
Leda oregona, 173, 188
Lucina acutilineata, 172

borealis, 170, 176, 17"^

richthofeni, 170, 187 88

species, 172
Lunatia horni, 166
Lytoceras sacya, 161
Macoma nasuta, 176, I'l )

secta, ISO

species, 170
Mactra (Spisula), species, 172
Mactra catilliformis, 177

falcata, 176, 177, 180, 181, 188

densata, 172, 180

species, 166, 183, 188
Margaritana subangulata, 182
Meretrix horni, 164, 166

uvasana, 165, 166
Metis (Lutricola) alta, 177, 180
Modiola ornata, 166
Morio tuberculatus, 166
Mulinia densata, 184
Mya arenaria, 179
Mytilus californianus, 176, 177

mathewsoni, 170, 186, 187

species, 179
Nassa arnoldi, 188, 204

californica, 180

perpenguis, 204

species, 177, 180
Natica, species, 172, 180
Nerita triangulata, 166
Neverita callosa, 170, 171, 172, 187, 188

globosa, 164, 165, 166

recluziana, 176, 177, 180
Nodosaria, 193
Oliva californica, 1S7, 188, 201

futheyana, 201
Ostrea attwoodi, 179

aviculiformis, 166, 194

idriaensis, 165, 166

sellaefonnis, 195

species, 176
Oxyrhina tumula, 177
Pachydesma inezana, 188
Pesten coalingaensis, 179, 180, 197

crassicardo, 171, 180, 181

discus, 169, 171, 172, 176, 177,
185, 188

estrellanus, 172, 176, 177, 187

etchegoini, 180, 198

nevadensis, 169, 187

oweni, 180

pabloensis, 181

peckhami, 169, 173

wattsi, 180, 198

species, 166, 170, 183, 187
Pectunculus scptentrionalis, 179, 180,

181, 197

veatchi, 161

species, 188
Perissolax brevirostris, 161
Physa costata, 182
Placuanomia inornata, 166
Planorbis tumens, 182
Pleurotoma (Clathurella) dumblei, 188,

204
Pleurotoma (Surcula), species, 180
Polymorphina (?), 193
Pomatiopsis intermedia, 182
Pseudocardium gabbi, 179, 184

species, 176, 180
Pulvulina, 193
Purpura, species, 177
Sagrina, 193

Saxidomus aratus, 180, 181
Scaphander jugularis, 187, 188, 201
Scutella gibbsi, 180, 181

species, 166, 171, 179, 183, 193
Sigaretus planicostum, 204

scopulosus, 188, 203
Sinum scopulosum, 203
Solen paralellus, 164

sicarius, 188

species, 170, 176, 188
Sphaerium dentatum, 182
Spondylus carloaensis, 165, 166, 194
Tamiosoma, 176
Tapes staleyi, 180

tenerrima, 176, 177

species, 170, 172
Tellina congesta, 173

ocoyana, 188

species, 106. 180, 188
Terebra cooperi, 188, 203

wattsiana, 203
Terebratella, 165

species, 166, 180
Trochita filosa, 187, 188

species, 176
Trochosmilia striata. 166
Trophon gabbiana, 176, 203

kernensis, 18.8, 202

ponderosum, 180, 202, 203

species, 176, 177
Turritella hofFmanni, IRS

ocoyana, 171, 172, 183, 187, 188

pachecoensis, 164, 166

uvasana, 164, 165, 166

species, 176
Vaginulina, 193
Venus (Chione) conradiana, 195

pertenuis, 195

temblorensis, 172, 188, 196
Venus (Mercenaria) pertenuis, 188
Yoldia cooperi, 170

impressa, 188
Zirphaea dentata, 176, 177

species, 172
Zygobates, species, 177

3 2044 103 22

Date Due

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