DEPARTMENT OF THE IBTEKIOB

BULLETIN

OF THE

UNITED STATES

.; '" 302,2,8

No. 15.\:

WASHINGTON

GOVERNMENT FEINTING OFFICE 

1885

UNITED STATES GEOLOGICAL SUKVEY

J. W. POWELL DIRECTOR

O3ST THE

IESOZOIC AND OENOZOIC PALEONTOLOGY

OF

CALIFORNIA

J;Y

CHARLES A. WHITE M. JD

WASHINGTON

CONTENTS.

Page. 

General remarks ............................................................ 7

The Chico-Tejon series ...................................................... 11

The Shasta Group............................................................ 18

Relations of the Shasta Group to strata beyond the limits of California... 22 

Relations of the fauna of the Auriferous Slates xto that of the Shasta Group. 24 

The geological age of the Aucella-bearing strata of California ............' 2(3

Certain Cretaceous strata which apparently belong between the Shasta

and the Chico Groups ............................................... 27

Remarks on certain California!! fossils which have been identified with

Eastern species ..................................................... 27

On the separation ot contemporaneous Cretaceous faunas in Western North

America............................................................ 30

Conclusion.............................................................. 31

Index .................................................................. 33

NOTES ON THE MESOZOIC AND CENOZOIC PALEONTOLOGY OF CALIFORNIA.

BY CHARLES A. WHITE.

GENERAL REMARKS.

Having been for a number of years engaged in the study of those 

Mesozoic and Oeuozoic formations of the United States which lie between the one hundredth and one hundred and fourteenth meridians, it 

became desirable that I should make some comparisons of them with 

the formations of similar age which are known to constitute important 

portions of the geological series as it is developed in the Pacific coast 

region. Dr. G. F. Becker, in charge of the Pacific division of the Survey, "in the course of his investigations also found it necessary to the 

proper elucidation of certain of the problems involved in his work that 

some special paleontological studies should be made in connection with 

it. I therefore, by request of the Director, devoted the season of 1884 

to such investigations as have a direct bearing upon the Mesozoic and 

Ceuozoic formations of California, extending my field observations to 

numerous localities within that State and to certain localities in Oregon 

also. These investigations were pursued in association with Dr. Becker, 

who gave his attention to the more purely geological questions with 

which they are intimately connected. The results of our respective 

studies are published in companion bulletins of the Survey, Nos. 15, 

(the present one,) and 19.

While only a few months have been given especially to this work upon 

the Pacific coast, I have had the advantage of a previous acquaintance 

with the results of the labors of all other authors who have written upon 

the paleontology of California; and these advantages I deem sufficient 

warrant for the conclusions which I have reached, and for their publication in the present form. Upon undertaking this work the questions 

which seemed more especially to demand my attention were, first, the 

true geological age of the Tejon Group of the California geologists, and 

its relation to such of the associated groups as they had also recognized, 

that is, the relation of that group to the Miocene above and to the Chico 

and Shasta Groups beneath ; second, the relation between the Chico and 

the Shasta Groups; third, the relation of the Shasta Group to the other

(7) 7
8 NOTES ON THE PALEONTOLOGY OF CALIFORNIA. IBUIX. 15.

Cretaceous formations, and to the so-called Auriferous Slates of California.

One of the principal obstacles to the satisfactory accomplishment of 

this work has been found in the fact that the fossil faunas of the Pacific coast region differ so greatly from those which are presumably of 

the same age respectively in other parts of the continent. Indeed, a 

conspicuous feature of the paleontology of that western region, at least 

as regards the formations from the Shasta, to the Tejon Group, inclusive, 

is the great paucity, and perhaps the entire absence, of fossil species in 

those formations respectively which are identical with any that are 

found in formations presumably of the same age which lie to the 

eastward of that region.1 Similar remarks will also apply to the Miocene and later deposits of the Pacific coast. Furthermore, the Carboniferous fauna of that region, so far as it is known, presents marked 

differences from that of any of the divisions of the Carboniferous series 

as it is known in other parts of North America. Therefore, in the 

paleontological study of the Pacific coast formations one must discuss 

their respective equivalent formations in 'other parts of the continent 

and in other parts of the world mainly with reference to the generic and 

family types which are represented in their respective faunas. This 

dissimilarity between the fossil faunas of 'corresponding formations of 

the Pacific coast region and of the central and eastern portions of this 

continent is quite as great as it is between corresponding formations 

in Eastern North Aulerica and Europe. In many cases, indeed, one may 

discuss questions concerning the equivalencies of formations in Eastern 

North America and Europe, respectively/ with more confidence than 

similar questions concerning the 'formations of eastern and western 

portions of North America.

In discussing the paleontological questions here proposed I shall have 

frequent occasion to refer to geological structure ; and it will be necessary for me to use in this connection the classification of strata which 

was proposed by the State geological survey of California for that region, and which has become generally accepted by geologists. A portion of that classification, however, was not regarded by the geologists 

of the California survey as f ally established, and it was proposed by them 

only provisionally. It is proper for me to say in this connection that 

not only do these provisional portions of that classification still remain 

unsettled, but that I also find the limits, both faunal and stratigraphical, 

of a part of the formations which they fully recognized to be indefinite 

and of doubtful character.

My season's field work upon these formations has been in a good de1 Some Chico fossils have, however, been found to the eastward of the Cascade 

Mountains, in Oregon ; but the extent of the formation which contains them there, 

and its relation to the Cretaceous strata further eastward, is not known. See remarks on subsequent pages concerning the identification of California fossils with 

Eastern species ; also remarks on the separation of contemporaneous Cretaceous faunas.

(8)
GENERAL REMARKS. 9

gree satisfactory, because I was able to collect in person many of the 

species of fossils which characterize the respective groups of strata, and 

because I was able to verify numerous unpublished observations previously, made by Dr. Becker, besides many others which were made 

still earlier by Prof. J. D. Whitney, the results of which are published 

in the State Geological Reports of California.2 In fact I have verified so 

many of the published observations of Professor Whitney that I do 

not hesitate to accept his statements in such other causes as I shall find 

it necessary to refer to in the following discussions.

I find the case somewhat different, however, as regards the work done 

by Mr. W. M. Gabb in connection with the geological survey of California ; but the adverse views which I have formed in relation to it refer much more to the conclusions which he reached than to the published details of his observations and of his descriptive paleontology.3

Taking up the subjects which it is proposed to discuss in this article, 

in the order in which they .are mentioned in a previous paragraph, we 

have first to consider the Tejon Group. In his studies of the Mesozoic 

and Cenozoic formations of California, Mr. Gabb recognized four groups 

of strata as referable to the Cretaceous period ; and this classification 

was officially adopted by the geological survey of that State. As one 

looks through the published:"writings of Mr. Gabb in relation to the 

grouping of the California strata, and their age and relations to the recognized groups of North America and Europe, a certain want of harmony appears in regard to the statements which h6 has made. I think 

it is only just to say that I regard this as largely due to the modification which his views necessarily underwent during the progress of his 

work, although he appears not to have made any explicit statements to 

that effect in any of his later publications. I shall therefore refer more 

especially to his later utterances, as I find them in the various publications to which he has contributed, especially in Yol. II, Paleontology of 

California, omitting as far as practicable material reference to his earlier views, although many of the discussions which have arisen in relation to them refer to the latter.

The following paragraphs, copied from Professor. Whitney's preface 

to Vol. II, Paleontology of California, pp. xiii and xiv, give a concise 

account of those formations in accordance with Mr. Gabb's later views 

and as they were finally adopted by the State survey. It is these formations alone that I propose to discuss in this article, and I shall consider the other formations of that region only in their relation to these.

1. The Tejon Group, the most modern member, the Division B of Paleontology, Vol. 

i, is peculiar to California. It is found most extensively developed in the vicinity of

8 See Vols. I and II, Paleontology, and Vol. I, Geology of California.

3 Mr. Gabb's work on the fossils of California is mainly contained in Vols. I and II 

of the Paleontology of California, but the following papers may be referred to for 

other discussions which relate to his work in that State: American Journal of Conchology, II, pp. 87-92; V, pp. 5-18; American Journal of Science, (2), XLIV, pp. 226- 

229; Proceedings of the California Academy of Science, III, pp. 301-306; V, pp. 7-8.

(9)
10 NOTES ON THE PALEONTOLOGY OF CALIFORNIA. [BULL. 15.

Fort Tejon and about Martinez. From the latter locality it forms an almost continuous belt in the Coast Eanges to Marsh's, 15 miles east of Monte Diablo, where it sinks 

under the San Joaquin Plain. It was also discovered by different members of the survey at various points on the eastern face of the same range as far south as New Idria, 

and in the summer of 1866, by Mr. Gabb, in Mendocino County, near Round Valley, 

the latter locality being the most northern point at which it is yet known. It is the 

only coal-producing formation in California.

This group contains a large and highly characteristic series of fossils, the larger 

part peculiar to itself, while a considerable percentage is found to extend down into 

the next group, and several species still further down into the Chico Group. Mr. 

Gabb considers it as the probable equivalent of the Maestricht beds of Europe.

2. The Martinez Group is proposed provisionally, to include a series of beds, of 

small geographical extent, found at Martinez and on the northern flank of Monte 

Diablo. It may eventually prove to be worthy of ranking only as a subdivision of 

the Chico Group.

3. The Chico Group is one of the most extensive and important members of the 

Pacific coast Cretaceous. Its exact relations with the formation in Europe have not 

been fully determined, though it is on the horizon of either the Upper or Lower Chalk 

and may prove to be the equivalent of both. It is extensively represented in Shasta 

and Butte Counties and in the foot-hills of the Sierra Nevada as far south as Folsom, 

occurring also on the eastern face of the Coast Ranges bordering the Sacramento Valley, at Martinez, and again in Oristimba Canon, in Stanislaus County. It includes all 

the known Cretaceous of Oregon and of the extreme northern portion of California, 

and is the coal-bearing formation of Vancouver's Island.

4. The Shasta Group is a provisional name, proposed to include a series of beds of 

different ages, but which, from our imperfect knowledge of the subject, cannot be 

separated; it includes all below the Chico Group. It contains fossils, seemingly representing ages from the Gault to the Neocomian, inclusive, and is found principally 

in the mountains west and northwest of the Sacramento Valley. Two or three of its 

characteristic fossils have been found in the vicinity of Monte Diablo, and one of the 

same species has been sent from Washington Territory, east of Puget Sound. Few or 

none of its fossils are known to extend upwards into the Chico Group.

(10)
THE CHICO-TEJON SEBIES.

It appears from Mr. Gabb's later publications that he recognized that 

all the strata from the base of the Chico Group to the top of the Tejon 

form an unbroken portion of the great geological series. And yet, with 

perhaps the exception of his Martinez division, which he proposed provisionally, he always discussed those divisions as if they were as distinctly definable as geological formations usually are. Geologists will 

probably always find it convenient to retain the names Tejou and Chico 

for the upper and lower portions of this series, respectively, but I have 

not been able to find any good reason for retaining the name Martinez 

Group for any portion of it. I shall therefore reject the Martinez Group 

so far as my own discussions of the series here referred to are concerned.

The first published fossils of that series of strata which afterward 

received from the California survey the name of Tejon Group were obtained by parties of the Pacific Bail-road surveys, some thirty years 

ago. These fossils were described by Mr. T. A. Conrad in the reports 

of that survey, and by him referred to the Eocene Tertiary.4 So far as 

I am aware, he never changed his mind as to the geological age of these 

fossils, nor of the group of strata from which they and many others 

were afterward obtained. On the contrary, he repeated the publication 

of his views 5 and strongly contended for their accuracy. Mr. Gabb 

alone, so far as I am aware, has published any of the fossils of the Tejon 

Group as of Cretaceous age; and this be did with a positiveness of assertion which, while it left no doubt as to his views, is only warranted 

in cases where the evidence is abundant and unquestionable from any 

reasonable standpoint.6

The publication of Mr. Gabb's views witii the sanction and in the 

reports of the geological survey of California gave the matter so much 

the air of authority, that various authors accepted those views as to the 

Cretaceous age of the Tejon Group, and for several years after Conrad's 

death it was not seriously called in question.

Professor Dana, however, has practically called those views in question, suggesting that the Tejon Group is of Eocene age, and probably 

equivalent with the Laramie Group.7

4 See Pacific Eailroad Reports, Vol. V, pp. 317-329.

6 See Ainer. Jour. Sci., (2), XLIV, pp. 376-377; Amer. Jour. Conch., I, pp. 362-365; 

II, pp. 97-100; Sinithsouian Check-List of Eocene Fossils.

6 See especially Proc. California Acad. Sci., Ill, p. 301.

7 See Dana's Manual of Geology (1876), p. 491.

(11) 11
12 N6TES ON THE PALEONTOLOGY OF CALIFORNIA. [BULL. 15.

In 1882, howeve'r, Prof. Angelo Heilprin, having access to the greater 

part of the type specimens of' Mr. Gabb's species of the Tejon Group, 

took up the study of the subject, and reached the conclusion that this 

group, as it was recognized by the California survey, is of Eocene Tertiary and not of Cretaceous age, and published his views in the Proceedings of the Academy of Natural Sciences of Philadelphia.8

This is the most eloborate and important paper that has been written 

upon the subject, and, as it accords mainly with the conclusions which 

I have reached, the reader is referred to it for many details which it is 

impracticable to present in this article. In that publication Professor 

Heilprin groups together all the species which have been referred to 

the Tejon Group by Mr. Gabb, and shows that, although fragments of 

Ammonites have been found among them, being such as are usually 

referred to the Cretaceous, much the larger part of the species are such 

as are commonly regarded as distinctively tertiary.

A few months after the publication of Professor Heilprin's paper, Prof. 

Jules Marcou published in the Bulletin of the Geological Society of 

France, an article on the geology of California, as the results of his 

personal studies in that State several years ago. In this article Professor Ma.rcou also contends for the Tertiary age of the Tejon Group.9

The fossils published by Mr. Gabb in the two volumes of the Paleontology of California as characterizing the Tejon Group comprise a large 

number of molluscan species. A small part of those species are so suggestive of a Cretaceous fauna, according to the hitherto accepted standards, that no paleontologist, viewing them separately, would hesitate 

to pronounce the strata from which they came as of Cretaceous age. 

Others of these fossils belong to genera which have so wide a range in 

time, that they are not relied upon by paleontologists as definite indices 

of geological periods. .But the greater part of these published Tejon 

species belong to genera which paleontologists are generally agreed 

upon as indicating the Tertiary age of the strata which bear them, as 

has been shown by Professor Heilprin.

Since in all other parts of the earth where the Mesozoic and Cenozoic 

strata have been fully studied the boundary, both fauual and stratigraphical, between the Upper Cretaceous and Lower Tertiary has been 

found to be well defined, many persons, apparently regarding that condition as the natural or normal one, have believed that the commingling 

of the Tertiary and Cretaceous types which was shown by Gabb's publications really did not originally^ exist in nature, but that it was due to 

some accidental or adventitious causes. 10 While the commingling of 

Cretaceous with Tertiary types in the same strata probably does not

8 SeeProc. Acad. Nat. Sci. Philad. for 1882, pp. 195-214. This paper is also reproduced in Professor Heilprin's Contributions to the Tertiary Geology and Paleontology of the United States, 4°, Philadelphia, 1884.

9 See Bulletin de la Socie'te' Ge~ologique de France, (3), t. XI, 1883, pp. 407-435.

10 See Conrad's remarks, Am. Jour. Conch., II, pp. 98 et seq.

(12)
WHITE.] CHICO-TEJON SERIES. 13

exist to as extreme a degree as seems to be indicated in some of Mr. 

Gabb's earlier writings, I am satisfied that such a commingling does 

exist to a large extent, as before indicated, and that an alternate commingling of species exists throughout the whole of the Chico-Tejon 

series. That the upper part of this series is almost purely of Eocene 

character, and that the lower part is as distinctly Cretaceous, is, 1 think, 

undeniable. Still, I am satisfied that no definable horizon exists in 

that series which will separate all the Cretaceous from the Teriary, and 

that no lines can be drawn which will separate a median portion of the 

series, in which all the commingling of types takes place.

In all the publications of the California survey the fact is made apparent that no distinct line of demarkation, either paleontological or 

stratigraphical, has been recognized in separating the Tejon from the 

Chico Group; and yet Mr. Gabb constantly refused to admit that 

the California strata in question might really constitute atxmtinuous 

series, embracing both Cretaceous and Tertiary strata.11 Indeed, at 

that time such wiews would probably have found little favor among 

paleontologists if he had entertained, and published them. He seems 

to have considered it necessary that any unbroken series of strata, however great, should be referred to one and the same period; and in this 

instance he chose the Cretaceous: while Professor Marcou seems to have 

chosen the Tertiary, and with quite as much if not more reason.

The results of my field work in California, including an examination 

of, the localities from which Mr. Gabb obtained many of his type specimens of both Tejon and Chico species, have convinced me of the general 

accuracy of his statements as to the horizons from which his fossils came 

when he collected them himself. They have also confirmed my opinion 

that the unbroken series of strata which comprise the Chico and Tejon 

Groups of the California geologists repesent together the closing epoch 

of the Cretaceous period and the opening or Eocene epoch of the Tertiary-.

The*most satisfactory illustration of the intimate stratigraphical conr 

nectiou between the Chico and Tejon Groups which I have examined 

occurs near New Idria, Fresno County, California, where ah extensive 

series of strata embracing these two groups is fully exposed. My attention was called to this series by Dr. Becker, who had studied it as a 

part of the geology of the New Idria district, which he has investigated 

in connection with his work on the quicksilver deposits of the Pacific 

coast. The strata in question had also been studied by members of the 

State geological survey of California, and they embrace one or more of 

the localities from which Mr. Gabb obtained the types of some of his 

Tejon species of fossils. This series of strata is there well exposed, being comparatively free from soil or debris; is composed mainly of sandstones and sandy shales, and lies on the northern slope of the range of

11 See especially Proc. Cal. Acad. Nat. Sci., Ill, pp. 302. 

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14 NOTES ON THE PALEONTOLOGY OF CALIFORNIA. [BULL. 15.

hills, the central mass of which is composed of the metamorphic strata 

which bear the quicksilver deposits of the New Idria mines. They dip 

to the northward, the angle of dip being high near their contact with 

the metamorphic series, upon which they rest unconformably, as shown 

by Dr. Becker; but the dip materially diminishes to the northward. 

From its contact with the metamorphic rocks the series in question extends northward a distance of about four miles, where it is apparently 

terminated by a fault, so that its connection with the Eocene is not there 

shown. From the contact with the metamorphic rocks before mentioned 

the thickness of this whole series of strata is estimated by Dr. Becker 

to be about 10,000 feet, and in my opinion it is no less.

Dr. Becker, with his assistants, carefully searched this whole series of 

strata for the purpose of collecting its fossils, and also to ascertain the 

conditions of its stratification. Upon the latter subject he reached the 

opinion that this whole assemblage of strata, nearly two miles in thickness, forms one continuous series from top to bottom, and that the sedimentation which resulted in the production of these strata was uninterrupted 

from the beginning to the end of the time in which it occurred. After a 

somewhat careful personal study of this series upon the ground, I have 

accepted Dr. Becker's conclusions as to the points just mentioned.

Although this New Idria series is understood to be practically an 

unbroken one, there is near its middle a recognizable change in the 

aspect of the strata, so that in appearance, and to some extent in the 

character of the stratification, the upper half differs from the lower half. 

It is upon this indistinctly definable horizon that Dr. Becker divided 

the series into two groups, for the purpose of arranging the results of 

his studies of them. So far as can be determined, this indistinct line 

accords with the necessarily artificial division that has been made of the 

series into the Chico and Tejon Groups, since the series is recognized 

as containing only these two groups, and the line of demarkation between them, as before shown, cannot be expected to be distinct. Fossils 

were collected by Dr. Becker's party from various horizons in the series, 

but in a large portion of it none were found, and those from the lower 

or Chico portion are very few. These latter are, however, of characteristic types, being species of Ammonites, Baculites, Trigonia, Inoceramus, 

and Lima. It is proper to mention that in this New Idria series of 

strata no commingling of the Cretaceous species above referred to with 

Tertiary types of fossils was actually observed j but very few fossils 

of any kind were obtained at this locality, especially in the lower portion of the series. Still, the intimate relation of the Chico and Tejou 

Groups for this -particular locality is well shown by the unbroken character of the series of strata which here constitutes both groups.

The exact equivalents of this New Idria series of rocks are found in 

the vicinity of Martinez, in Contra Costa County, as well as in other 

parts of California. At Martinez and other localities a commingling 

of Cretaceous and Tertiary types such as has already been referred

(14)
WHITE.] CHICO-TEJON SERIES. 15

to actually occurs ; but in all cases the Tertiary types appear to increase 

towards the upper part of the series and the Cretaceous types towards 

the lower part. In other words, it appears that the base of the series 

has a preponderance of Cretaceous types, and the upper part a preponderance of Tertiary.

Besides the evidence afforded by the character of the contained fossils, 

the opinion that the Tejon Group really represents the Eocene is further 

supported in that no other representatiye of the strata of that epoch 

has been discovered in California, and also the Miocene strata everywhere rest conformably upon the Tejon. This conformity was recognized by the members of the State geological survey of California, and 

it has also been observed in numerous cases by Dr. Becker, as well as 

in several instances by myself. One of these observations I made at 

the well-known Tejon and Miocene locality at the head of Vallecitos 

Canon, near the place mentioned as " Griswold's" in the California reports, which is only a few miles from the New Idria locality, just referred to.12 I there satisfactorily traced the strata from one formation to 

the other, and found that not only is the conformity of the two formations with each other clearly apparent, but no break in the order of 

stratification could be detected between those layers which contain 

characteristic Tejon fossils, on the one hand, and those which contain 

equally characteristic Miocene fossils, on the other. In short, I found 

no room there for the existence of any Eocene strata other than the 

Tejon.

The character of the fossils which are found in the formation thus resting conformably upon the Tejon is such that their Miocene age has never 

been called in question; and the California geologists who regarded 

the Tejon Group as of Cretaceous age necessarily considered the Eocene 

as unrepresented among the strata of that State. It is proper to say, 

however, that the difference between the Tejon and Miocene faunas, as 

regards specific forms, is well marked ; so that, so far as I am aware, 

none of the species of the former pass up into the latter formation. A 

few of the species of each of the-two formations are closely related, 

and it is possible that some of them may yet prove to be specifically 

identical. While the Miocene strata of California seem, to have been 

deposited upon the Tejon Group by continuous sedimentation, these two 

groups are not so intimately related by their fossils as the Tejon and the 

Chico Groups are. Still, I am of the opinion that this faunal difference 

between the Tejon and the Miocene strata does not necessarily represent a material difference of time.

From the foregoing remarks it will be seen that there exists in California a comformable and intimately connected series of strata representing the latest epoch of the Cretaceous period to the Miocene, inclusive. The base of this series, as shown by Dr. Becker, rests unconform13 See Geology of California, Vol. I, p. 56. 

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16 NOTES ON THE PALEONTOLOGY OF CALIFORNIA. [BULL. 15.

ably upon all the other rocks with which it has been found in contact, 

and, as shown by the California reports, the Pliocene rests unconformably upon the Miocene.

No proposition seems to me to be more reasonable than that wherever 

any portion of the great geological series is complete the line of demarkation between any of the formations must necessarily be indistinct, 

and that there will be a commingling of the species which any two adjacent formations contain, upon both sides of any such line as may be 

recognized. Such a condition of things would as naturally exist in 

strata representing the confines of any two geological ages as in the 

case of those of any two formations of any one age. Therefore, if the 

geological series is complete, there ought to be no greater break between the Cretaceous and the Tertiary than between any of the subdivisions of either. It is nevertheless true that geologists have always 

recognized a marked paleontological break between the uppermost Cretaceous and the lowermost Tertiary strata, both in this country and in 

Europe. Sir Charles Lyell remarks as follows upon this subject, and 

the statements of other European authors are to the same effect:

The marked discordance in the fossils of the Tertiary as compared with the Cretaceous formations has long induced many geologists to suspect that an indefinite 

series of ages elapsed between the respective periods of their origin. Measured, indeed, by such a standard, that is to say, by the amount of change in the fauna and 

flora of the earth effected in the interval, the time between the Cretaceous and the 

Eocene may have been as great as that between the Eocene and Recent periods. 13

The Maestricht, Faxoe, and other beds of Europe, although they are 

intermediate between the Upper Chalk and the Eocene, are too closely 

related by specific and generic forms to the Chalk to be regarded as 

separate from the Cretaceous proper. Their faunal relations to the 

Eocene are also too remote to allow of their being regarded as in any 

proper sense transitional between the Cretaceous and Tertiary. In New 

Zealand, however, it appears probable from the reports of the Government geological surveys that there is in those great islands a true transition from the Cretaceous to the Tertiary, similar to that which occurs 

in California.

I think the evidence which has been adduced to show the Eocene age 

of the upper or Tejon portion of the Chico-Tejon series is as conclusive 

as any evidence of that kind can be. Now, if we apply the paleontological standard for indicating the age of formations which is generally 

accepted by geologists, we necessarily refer the fossils of the lower or 

Chico portion of that series to the Cretaceous. The question then 

arises: to what portion of the full Cretaceous series, as it is recognized 

in other parts of the world, is the Chico Group really equivalent 1? 

If the Tejon Group is Eocene, it is plain that the Chico Group represents the upper portion of the Cretaceous, and it necessarily represents 

the very latest portion of that period. My opinion, therefore, is that it

> 3 See Lyell's Elements of Geology (1871), p. 281, 

(16)
WHITE.] CHICO-TEJON SERIES. 17

is, at least in part, later than any formation that has yet been referred 

to the Cretaceous period either in Europe or in America, and that it 

practically fills the gap which is indicated by the passages just quoted 

from Sir Charles Lyell.

An examination of the figures and descriptions of the fossils which 

Mr. Gabb has referred to the Chico Group, together with his catalogue 

of California Cretaceous fossils, 14 shows that while a considerable portion of them, especially the Cephalopoda, are of types which indicate 

their Cretaceous age, a large part of them are of genera which are known 

to, range from the early Cretaceous to the present time, and some of 

them belong to genera which are generally accepted as not older than 

the Tertiary. Therefore there appears to be no inherent reason why 

this Chico fauna, even as it is represented by Mr. Gabb, should not be 

regarded as belonging to the very latest portion of the Cretaceous period. 

The fact that one or two Mesozoic types of Cephalopods pass up from 

these strata into those of the Tejon portion does not necessarily prove 

that the latter ought also to be referred to the Cretaceous, any more 

than the discovery of Ammonites in tho Carboniferous of Texas and 

of India ought to require us to refer those strata to the Mesozoic.

The intimate relation to each other of all the strata of this great ChicoTejon series, as shown by the mixed character of its fossils, is very perplexing when that condition is considered in relation to the established 

taxonomy of the formations, but it is very suggestive when considered 

with reference to a search after the complete sequence of geological 

events. Indeed, such a condition of things is what one ought to expect 

to find somewhere; but hitherto no other part of the world, if we except 

New Zealand, has furnished so striking an example of the intimate connection of two geological ages, or at least of such connection between the 

Cretaceous and the Tertiary.

14 See Vols. I and II, Paleontology of California-, for the figures and descriptions, and 

Vol. II, pp. 209-254, for the catalogue. 

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Bull. 15 2
THE SHASTA GROUP.

When Vol. I of the Paleontology of California was published it 

appears that the Shasta Group was not recognized by the California 

geologists. At that time Mr. Gabb divided the rocks which he referred 

to the Cretaceous period into two portions, which he designated respectively as Divisions A and B.15 His line of separation between these 

two divisions was the same as that by which he afterwards separated 

his Tejou and Chico groups.16 A part of the fossils which he published 

in Vol. I as belonging to Division A belong really to the Shasta 

Group,1* the separate existence of which he had not then recognized. 

He did not then recognize these Shasta fossils as belonging to the age 

of the Gault or Neocomian, as he afterwards did, but he 'regarded all 

the Cretaceous strata of California as representing the epoch of the 

White Chalk of Europe.18 For this classification of the California strata, 

however, he afterward, in Vol. II, substituted that which has already 

been quoted on page 9. In Vol. II the Shasta Group is proposed 

to receive all the Cretaceous strata of that region which are older 

than the Chico Group. The entire separateness of the Shasta from 

the Chico Group is there recognized, and it is also stated to embrace strata of different epochs, probably representing a range from 

the Gault to the Neocomian.19 This latter view I am disposed to adopt 

as at least approximately correct, although it is not yet clear what division ought to be made of the strata that have been grouped together 

under the name of the Shasta Group ; but this question will be discussed further on.

Whatever may be the relation of the Shasta strata among themselves, 

it seems to be certain that there is an abrupt hiatus, both stratiffraphical 

and paleontological, between the Shasta Group and the Chico Group, 

the former representing a portion of the period not later than its middle, and the latter its closing portion. It has been generally understood that the marine Cretaceous deposits of the United States, as they 

are found in the Atlantic, Gulf border, and interior regions, representonly the Upper Cretaceous of Europe, none of them probably being 

any older than, if so old, a,s the Gault. If, then, the Chico is, as it is

1B See Paleontology of California, I, p. xix, and Proceedings of the California Academy of Sciences, III, p. 302. 

16 See Paleontology of California, II, p. xiii.

17 See especially the Cephalopoda, published in Vol. I, Paleontology of California.

18 See Paleontology of California, I, p. xix. 

19 See Paleontology of California, II, p. xiv.

W (18)
WHITE.] SHASTA GROUP. 19

here assumed to be, later than any other Cretaceous strata known in 

Europe or America, and the Shasta Group is as old as the Gault, or 

older, we have a hiatus in the California Cretaceous series which is 

equal to all the time in which all the other known Cretaceous deposits 

of the United States were formed. Although such a conclusion seems 

to be a plausible one from our present methods of reasoning, we unfortunately lack the proof of it which specific identity of Cretaceous fossils 

on each side of the Sierras would afford. It is proper in this connection 

also to state that Mr. Gabb reports three species of Cephalopoda as 

common to the 8hasta -and Chico Groups, namely, Ammonites batesii, 

, A. remtndii, and Ancyloceras lineatus.20 If Mr. Gabb is correct in these 

references, it seems to point to a closer fauna! relation between the Chico 

Group and the Horsetown beds of the Shasta Group than would be expected were the hiatus between them as great as is implied by referring 

the latter to the age of the Gault and the former to the latest portion 

of the Cretaceous period.

The strata which received the name of Shasta Group from the geologists of the State survey of California occupy only a few isolated areas 

in that State. Each of these areas is not only of small geographical extent, but the strata in every case are either uncon form able with the 

rocks both above and below them, or they are so much disturbed that 

their stratigraphical relations are obscure. The strata of these separated portions of the Shasta Group of California, judged by the fossils 

which they respectively contain, seem to represent at least two epochs 

of the Cretaceous period. Our knowledge of those strata and their fossils is not quite sufficient to warrant the formal separation of the former 

into two distinct groups, in the sense in which that name for assemblages of strata is generally used, but two divisions are plainly indicated by the fossils. I shall therefore, for the present, retain the name 

of Shasta Group in the general sense in which it was used by the geologists of the California survey; but for the purpose of convenience 

in the references which I must necessarily make in this article to those 

two divisions, I shall designate them as the Horsetown beds and the 

Knoxville beds, respectively. These names are suggested by the two 

localities from which the best collections of the fossils of each of these 

two divisions were obtained.

The Horsetown beds have been found mainly in Shasta County.and 

the Knoxville beds mainly in Lake, Colusa, Contra Costa, and Santa 

Clara Counties. These two divisions have never been found in contact, 

nor under such circumstances as will enable us to say with certainty 

which of the two is the older. From paleontological considerations, 

however, the character of which will appear further on, I am inclined 

to regard the Knoxville beds as older than the Horsetown beds. The

20 Mr. H. W. Turner has also found an Ammonite in the Chico Group near Monte 

Diablo which, if not specifically identical with Ammonites aloliczkanue Gahb, is very 

closely related to it. The original specimens came from the Shasta Group.

(19)
20 NOTES ON THE PALEONTOLOGY OF CALIFORNIA. [BULL. 15.

latter, although they have a much less known geographical extent, certainly contain a more abundant and varied fauna than the former. It 

is especially rich in the Cephalopoda, as will appear by referring to the 

California reports, where the fossils of this division are recorded as coming from " the, North Fork of Cottonwood Creek, Horsetown," etc. 

Furthermore, many of the types which the fauna of the Horsetown 

beds embraces are such as paleontologists use with more confidence as 

indices of the geological position of the strata containing them than 

they do any of those which are embraced by the fauna of the Kuoxville 

beds, as it is at present known.

The following species which were published by Mr. Gabb in the California reports are regarded as having come from the Knoxville beds 

at different localities in California. The interrogation marks after three 

of them express a doubt as to the correctness of my identification of 

the species, Mr, Gabb having obtained his type specimens of those species from the Horsetown beds. All the other species which are mentioned in Gabb's Catalogue of California Cretaceous Fossils as belonging to the Shasta Group21 1 regard as having come from the Horsetown 

beds. 

The following is a list of the species just referred to:

Ammonites ramosus Meek?

Belemnites impressus Gabb.

Palcetractus crassus G.

Cordiera mitrceformis G.

Atresius liratus G.

Potamides diadema G. ?

Ringinella polita G.

Liocium punctatum G.

Modiola major G.

Aucella piochii G.

Rhynchonella wMtneyi G.

Lima shastaensis G. ?

Pecten complexicosta. G.

In addition to these published species the following have been generically recognized amoDg the collections which have been obtained by Dr. 

Becker and his party from Knoxville, Cal., all the specimens of which

are, however, too imperfect for specific determination : Ammonites 9, Margariiaf, Dentalium, Area, Nuculana, and Rliynclionella. Besides all these

forms there are fragments among the collections from Knoxville which

indicate two Or three Other molluscan species which are riot considered.

in my enumeration of the fauna of the Knoxville beds. The specimens 

which have been referred to as probably representing a species of Ammonites are only a few small fragments, which show only portions of 

the sides and periphery of the shell. These seem to indicate a species

21 See Paleontology of California, II, pp. 209-254.

(20)
WHITE.] . SHASTA GROUP. 21

i

related to the A. newberryi of Meek. The Dentalium is probably undescribed, as are also probably the Area and Nuculana. The Rhynchonellais apparently an undescribed species, and seerns to be identical with 

one which I discovered last summer at Horsetown.22 The collection 

contains only one fragment of the shell which I have referred with 

doubt to Margarita.

The specimens of Ammonites which in the foregoing list of published 

species I have referred with doubt to A. ramosusMesk consist only of 

the small inner whorls, none of them reaching an inch in diameter. 

The form, surface markings, and se.pta of the shell, so far as these characters are shown by the Knoxville specimens, seem, however, to agree 

well with those of the species as it is described by both Meek and Gabb. 

MeeVs type specimens came from Vancouver's Island, but Gabb identified the species in the Horsetown beds of the Shasta Group of California.23 The specimens of the shell which in the foregoing list I refer 

with doubt to the Potamides diadema of Gabb are imbedded in compact 

rock, so that all its characters cannot be observed. They are probably 

identical with Gabb's species, which he describes as coming from the 

Horsetown beds. Finally, so far as the specific identity of any Belemnites can be determined, there seems to be comparatively little reason 

to doubt that the specimens which have been found in the Horsetown 

and Knoxville beds, respectively, and referred to Belemnites impressus 

Gabb, are specifically identical.

Comparing these nineteen species of fossils now known to exist in the 

Knoxville beds with those from the florsetown beds, or, in other words, 

with all the other species which Gabb refers to the Shasta Group,24 we 

find that all except six of them are certainly different from any of the 

latter. One of these six, the Ammonites neivberryif?, offers only a mere 

suggestion of identity; four are probably, but not certainly, identical, 

namely Ammonites ramosus f, Potamides diadema?, Lima shastaensisf, 

and Rhynchonella ?; and the specific identity of one, Belemnites 

impressus, has been regarded as certain.* Detracting somewhat from the 

certainty of the last identification we have the fact that the Belemnites, 

as a rule, do not present salient or even satisfactory features by which 

to determine specific differences.

The dissimilarity between the faunas of the Knoxville and the Horsetown beds is still further shown by the abundance of Aucella in the 

former and its absence from the latter, so far as is now known, and 

also by the greater abuudance of the species which characterize the 

Horsetown beds and their general dissimilarity when compared with 

the few species which are yet known from the Knoxville beds. It is

22 This form is closely like the B. oxyoplicata of Fischer, from the Jurassic of Moscow.

23 See Bull. U. S. Geol. Sur. Terr. (1876), II, p. 371, PI. V, Fig. 1; also Paleont. California, I, p. 65, PI. XI, Fig. 13, and PI. XII, Fig. 126. 

84 See Gabb's Catalogue Paleout. California, II, pp. 209-254.

(21)
22 NOTES ON THE PALEONTOLOGY OP CALIFORNIA. IBULL.IS.

possible that the Aucella may yet be found to range up into the Horsetown beds, but even in that case there would remain a material difference 

between the faunas of the two divisions.

These differences between the faunas of the Knoxville and the Horsetown beds seem to indicate plainly that they were not synchronously 

deposited; but, as before remarked, there is yet no known stratigraphical proof as to which is the older. The character of the fossils of the 

respective faunas seems to indicate, however, that the Knoxville are 

older than the Horsetown beds; that is, the fossils of the Horsetown 

beds appear to represent the Gault, while the presence of Aucella in the 

Knoxville beds only would seem to indicate an age for them at least as 

early as the Neocomian. Furthermore, the affinities of some of the fossils of the Horsetown beds are with those of certain of the later Cretaceous formations to the eastward of the Sierras, while no such affinities have been recognized for any of the Knoxville fauna, with the 

doubtful exception of Ammonites complexus. In this article I shall take 

the foregoing view of the relative ages of the Knoxville and the Horsetown beds, although it implies the probable existence of a considerable 

hiatus between the two divisions of what is now known as the

Group.

RELATIONS OF THE SHASTA GROUP TO STRATA J3EYOND THE 

LIMITS OF CALIFORNIA.

Certain of the species which characterize the strata of the Shasta 

Group in California have been recognized among the collections which 

have been reported by different persons from Washington Territory 

and British Columbia, and also from Alaska and the Aleutian Islands. 

But none of the species of that group have been found in any North 

American strata to the eastward of the Pacific coast region, if we except Greenland. While it is probable that the Horsetown beds of California are represented in those northern localities which have been referred to, it is more especially the equivalent of the fauna of the Knox- 

 ville beds that has been recognized as existing there. This recognition 

is mainly through the identification, among the collections which have 

been made there, of the Aucella, which so strongly characterizes the 

Knoxville division of the Shasta Group in California. Specimens which

I regard as specifically identical with the form which Mr. Gabb published under the name of Aucella piocUi have been presented to the 

Survey by Prof. Thomas Condon, which he collected at Puget Sound, 

Washington Territory. Mr. Whiteaves refers to the same species as 

being abundant at Tatlayoco Lake and other places in British Columbia; 25 and Professor Eichwald, Dr. P. Fischer, and myself have pub26 See Trans. Roy. Soc. Canada,, Sec. IV, 1882, p. 84. 

(22)
WHITE.] RELATIONS OF THE SHASTA GROUP. . 23

lished forms which I regard as specifically identical with it, from different parts of Alaska.

Among the fossils collected in Alaska by Peter Doroschin, Eichwald26 recongized all the forms of Aucella which Keyserling had published as occurring in Eussia, namely, A. concentrica Fischer, A. mosquensis Von Buch, A. pallasi and A. crassicollis Keyserling. The last two he 

regards as only varieties of A. concentrica. , Dr. Fischer 27 recognized 

only one species among Pinart's Alaskan collections, which he referred 

to A. concentrica.

I also recognized only one species among the collections brought from 

Alaska by Mr. Dall. Although the specimens were numerous, and presented quite a wide variation of form, I regarded them all as representing a variety of Aucella concentrica.^ Mr. Whiteaves (loc. cit.) recognized only one species among the collections from British Columbia, and 

this he referred to Aucella mosquensis.

In the Knoxville beds of California there are two recognizable varieties of Aucella, which, while they are connected together more or less 

closely by intermediate forms, are still quite different in extreme examples. It is usually the case also that one variety will be found to 

prevail in certain layers of rock sometimes almost exclusively, and the 

other variety in other layers.

Adult examples of one of these varieties are large, robust, and often 

inflated. These I regard as approaching the typical forms of A. concentrica more nearly than the others. Those of the other variety are 

smaller, more slender, and have a more delicate appearance. They seem 

to correspond more nearly with the type of A. mosquensis. Still, after 

examining numerous examples from Alaska, British America, Washington Territory, and California, besides some Eussian examples of A. 

concentrica and A. mosquensis, which I regard as being authentic, in the 

collections of the Srnithsonian Institution, I am of the opinion that all 

of them represent only one species. Indeed, I am disposed to regard 

as at most only varieties of one species all the forms which have, from 

various authors, received the names Aucella concentrica, A. mosquensis, 

A. pallasi, A. crassicollis, A. piocliii, and A. erringtonii. However, it 

will be convenient, when discussing the Aucelto-bearing strata of California, to retain the names A. concentrica and A. mosquensis to indicate 

the more robust and the more elongate forms, respectively, as they occur 

in that State.

Before dismissing this reference to Aucella, it is well to note how wide 

is the geographical distribution.of the va,ria,ble form which has been 

known under the various names which have just been mentioned. This

26 See Goognost. Palaeont. Bemerkungen ueber (".ie Halbinsel Mangischlak und die 

Aleutischen Insoln, pp. 185-187, PL XVII.

37 See Voyage a la c6te Nord-Ouest de 1'Ame'rique, par M. Alph.-L. Pinart, pp. 33- 

36, PI. A.

28 See Bull. U. S. Geol. Survey, No. 4 (1884), pp. 13, 14, PI. VI.

(23) _
24 NOTES ON THE PALEONTOLOGY OF CALIFORNIA. [BULL. 15.

shell was first known in various parts of Bussia, and subsequently upon 

the eastern coast of the Caspian Sea,29 in Northern Siberia,30 on the island of Spitsbergen,31 on Kuhn Island (off the east coast of Greenland),32 

and in Alaska, British Columbia, Washington Territory, and southward 

to Central California, as mentioned on previous pages of this article. 

Although it is so variable in certain of its features, so constant is it in 

its general characteristics and its separateness from related forms that 

paleontologists are now generally agreed upon its identity in all the 

widely separated localities which have just been indicated.

RELATION OF THE FAUNA OF THE AURIFEROUS SLATES TO THAT 

OF THE SHASTA GROUP.

The opinion that Aucella erringtonii and A. piochii Gabb are specifically identical has been formed after having had better advantages for 

investigating the subject than seem to have been enjoyed by any other 

person who has written upon the paleontology of California. I have uot 

only examined -the original types of those two forms, but hundreds of 

other specimens of A. piochii from Gabb's original and from other localities. Furthermore, I made a personal visit to the locality on the Mariposa Estate where the type specimens of A. erringtonii were obtained, 

and collected better, specimens of it from the Auriferous Slates there and 

in the immediate neighborhood than have before been known. Dr. 

Becker and his assistant, Mr. H. W. Turner, accompanied me on that 

visit, when we also obtained from the same slates some fragments of an 

Ammonite, some impressions of a shell apparently the Pholadomya orbiculdta of Gabb, others that represent a species of the Pectinida3, perhaps 

the Amusium aurium of Meek, and still others which are undeterminable. 

Add to these the Belemnites pacificus of Gabb, and we have a fauna of 

the Auriferous Slates of the Mariposa Estate which amounts to at least 

five species of mollusks. It is true that only the Aucella has been satisfactorily identified as occurring in both the Auriferous Slates 33 and

29 See Eichwald's Geognost. Palaeout. Bemerkungen ueber die Halbiusel Maugischlak und die Aleutischen Inseln, p. 53.

30 See Middendorf 's Reisein den aussersten Norden und Osten Siberiens, erster Band, 

Theil I, p. 255.

31 See Lindstrom, Om Trias-oeh Jurafdrsteningar fran Spetsbergen. Kongl. Svenska 

Vetenskaps-Akad. Handlingar, VI, No. 6, p. 14.

32 See F. Toula, Die zweite deutsche Nordpolarfahrt, II, pp. 497-505; also Quart. 

Jour. Geol. Soe. Lond., XXXIV (1876), p. 560.

33 Some of the specimens found in the Auriferous Slates of the Mariposa Estate showmore or less distinct radiating lines, and I have observed the same peculiarity among 

examples from the Knoxville beds, as well as among Russian and Alaskan examplea.

(24)
WHITE.] FAUNAL RELATIONS OP THE AURIFEROUS SLATES. 25

the Shasta Group, but there is nothing in' the character of the other 

four species of mollusks from the Auriferous Slates which would render 

inconsistent their reference to the age of the Knoxville beds.

The specimens of. Aucella and other Auriferous Slate species just referred to were obtained by us from the rocks in situ; thtfse found near 

the left bank of the Merced Kiver. Mariposa County, Califb'rnia, about 

a quarter of a mile below Beuton's Mills, being especially satisfactory, 

as regards both their position in the strata and their condition of preservation. Efere the strata have an almost vertical dip, and they are 

plainly an integral part of the great Auriferous Slate series. A part 

of our collection, as well as»some of those which were collected by King, 

Gabb, and Miss Erringtou, were obtained from within a few feet of the 

famous great quartz vein which traverses the Mariposa Estate, and 

which is inclosed in the Auriferous Slates.

I did not obtain any specimens of Belemnites from the Auriferous 

Slates, as Gabb and King did, and I have not.seen a specimen of Gabb's 

B. pacificus, which he obtained from that formation, but which he did 

not figure. Judging from his description of that s.pecies, it seems probable that it is identical with my subsequently published B. macritatis. 

This last-named form was obtained by Mr. Ball in Alaska, where he 

found it associated with an abundance of specimens of the shell which 

I described in the same publication as Aucella concentrica var.,34 and 

which, as already stated, I regard as identical with- both A. erringtonii 

and A. piochii. ^

The great Auriferous Slate series is an immensely thick one, and in 

Northern California it is known to include strata of Carboniferous age. 

In Shasta County there is a considerable thickness of strata, apparently 

a portion of that great series which holds a position below the Carboniferious and between it and the Granite. These strata perhaps represent a still older Paleozoic formation; but no fossils have been found in 

them. The strata of the great Auriferous Slate series which are actually 

or presumably referable to Paleozoic age it is not my present purpose 

to discuss. Indeed, my only object with reference to that great series 

is to show that at least a part of it is of the same age as the Knoxville 

beds of the Shasta Group This I think is proved by the identity of 

Aucella piocMi and A. erringtonii, supported by the general character of 

the other fossils which the strata of both respectively bear. It is true 

that this is the only specific identification that has been made; but the 

species in question is one of extraordinarily wide geographical range, 

and it is also one of great constancy and exclusiveness as regards its 

distinguishing characteristics.

34 See Bull. U. S. Geol. Survey, No. 4, p. 13, PI. VI. 

(25)
26 NOTES ON THE PALEONTOLOGY OF CALIFORNIA. TBULL. 15.

THE GEOLOGICAL AGE OF THE AUCELLA-BEARING STRATA OF CALIFORNIA.

Now, as to the true geological age of the AwceMa-bearing strata of 

California I think the evidence is not wholly satisfactory. A discussion 

of this question for the Pacific coast region really involves a discussion of 

the whole question of the age of the Awce^a-bearing rocks of Europe, 

Asia, and North America. In view of my want of personal knowledge 

of the geology of those distant regions, and the great difference of opinion on this subject among geologists of repute, I am not prepared to 

discuss the question fully. Still, I am inclined to hold the view which 

I expressed in Bulletin No. 4, that these California strata and their Alaskan and British Columbian equivalents occupy a position upon the confines of both the Jurassic and the Neocomian. I suspect that the difference of opinion which has been referred to has arisen largely from the 

equivocal character of the faunas which are associated with Aucella in 

those districts concerning the strata of which the disputes have arisen. 

Eichwald and Whiteaves both contend that all the strata which bear 

Aucella concentrica and A. mosquensis are certainly of Neocomiari age. 

On the other hand, Keyserling, Trautschold, D'Orbigny, and others as 

confidently assert that they are of Jurassic age ; and paleontologists 

generally have hitherto regarded Aucella as an exclusively Jurassic 

genus. Even so late as the past year, Mr. A. Pavlow, a member of the 

official geological commission of Eussia, has, in a brief publication, 

placed the well-known strata which in eastern and other parts of 

Eussia bear Aucella concentrica in the Jurassic series, as the earlier 

Eussia,n geologists also did.35

I do not think that any satisfactory evidence has yet been presented 

to show that the genus Aucella is exclusively confined to either the Jurassic or the Neocomian, and I know of no reason why we may not expect to find species of it in both Jurassic and Neocoinian strata. There 

seems to me also to be no good reason why Aucella concentrica and A. 

mosquensis may not exist in Jurassic strata in Europe and Asia and in 

the Neocornian in America. It is well known that a considerable number of the Lower Carboniferous species of Europe are found in the Upper 

Carboniferous of North America ; and also that certain species pass 

from the Devonian to the Carboniferous.

If it shall finally appear that those strata of the Auriferous Slate series which bear Aucella erringtonii, together with their equivalents, must 

be referred to the Neocomiau rather than to the Jurassic, the existence 

of Jurassic strata in California is exceedingly doubtful, because all the 

other strata in that State which have been referred to the Jurassic are 

probably equivalent with these.

^See Bull. Soc. Ge"ol. de France, t.XII (sex. 3), June, 1884, pp. 686-696.

(26)
WHITB.] AUCELLA-BEARING STRATA WALL ALA STRATA. 27

CERTAIN CRETACEOUS STRATA WHICH APPARENTLY BELONG BETWEEN THE SHASTA AND CHICO THE GROUP.

Dr. Becker has obtained from strata exposed near the sea-shore at 

Wallala, Mendocino County, California, a small collection of fossils 

which are evidently of Cretaceous age, but all the species of which are 

apparently new, and different from any of those whicli have been found 

in either the Chico, or Shasta the Group. They seem to represent a different group of strata from any other fauna of which has yet been published ; and as the Budistse are usually regarded as characteristic of the 

median Cretaceous, this small fauna is supposed to belong to a series 

of strata which intervenes between the Shasta, and Chico the Group. 

Dr. Becker found no contact between the Chico and these beds, which 

lie unconformably upon metamorphic rocks, probably of the Knoxville 

series. The specimens are all in a bad state of preservation, but the 

following genera have been recognized: SphcerulitesV, Ostrea, Inoceramus, Pecten, Cylichna, Turritella, and Solarium.

Only two of these species, the Inoceramus and Splicer ulites, appear to 

be sufficiently characteristic to call for any special remarks. The Inoceramus is a very large, subelliptical, subdiscoidal form. The specimens are all much broken, but some of them indicate that the valves 

sometimes reached nearly a foot in diameter.

It is possible that the form which I have regarded as a species of 

Sphcerulites belongs to the genus Radiolites, but so far as its generic 

character can be determined from the crushed and fragmentary specimens, it appears to belong to the former genus. Upon comparing them 

with some specimens which were sent to the U. S. National Museum by 

Mr. C. It. Orcutt, from Todos Santos Bay, near San Diego, California, i} 

am quite confident they belong to the same species. The other species 

which Mr..Orcutt found associated with the San Diego specimens were 

few, but they are suggestive of certain forms found in the Gosaugebilde 

of Europe.

REMARKS UPON CERTAIN CALIFORNIA FOSSILS WHICH HAVE BEEN 

IDENTIFIED WITH EASTERN SPECIES.

Reference has already been made to those species found in California rocks which have been either definitely or provisionally identified 

with species already known in Cretaceous strata east of the Sierra Nevada. The following is a list of them, together with such remarks as 

seem to be called for in this connection:

NAUTILUS TEXANUS Shumard.

Dr. Shumard's type specimens of this species were from Texas. He 

described it in the transactions of the Saint Louis Academy of Science,

(27)
28 NOTES ON THE PALEONTOLOGY OF CALIFORNIA. [BULL.-15-

I, p. 590, but it was never figured by him. Mr. Gabb referred his 

California specimens only provisionally to N. texanus, and also doubtfully to the Shasta Group.36 After examining specimens from Shumard's original locality which I presume to belong to this species, I 

think it is not identical with the California form.

AMMONITES PERTJVIANUS Von Buch.37

Mr. Gabb, with much doubt, referred a fragment which he obtained 

from the Chico Group of California38 to the above-named species, as it 

has been recognized in Texas and the adjacent region. After an examination of Mr. Gabb's specimen, and also several authentic examples of 

the Texan form, I think Mr. Gabb might have expressed his doubts in 

even stronger terms.

AMMONITES COMPLEXTJS Hall & Meek.39

This species was originally described from the Cretaceous No. 4 of 

Meek & Hayden, at the Great Bend of the Upper Missouri Eiver. Meek 

afterwards recognize a variety of it among some collections from Vancouver's Island, to which he gave the variety name suciaensis.*0 Gabb 

found a fragment of an Ammonite in the Chico Group of California 

which he identified with that variety.41

There is much reason to doubt whether the Upper Missouri form and 

that of Vancouver's Island are specifically identical. Also the identification of the Californian and Vancouver's Island forms is not quite satisfactory, although it may be correct.

VOLUTILITHES NAVARROENSis Shumard.42

Shumard's shell was described from Cretaceous strata in Texas which 

are equivalent with the Eipley Group of Mississippi and Alabama. It 

has never been figured, and Mr. Gabb's comparisons were made only 

with Shumard's description. 43 He mentions some differences, and it is 

probable that others would appear if good and authentic specimens from 

both the eastern and the western strata could be compared.

0

TURRITELLA SAFFORDI Gabb.44

From the figures given by Gabb in the two publications here cited, it 

is evident that the eastern and western forms are closely related, and it 

may be that it will not be practicable to say that they are different.

36 See Paleontology of California, I, p. 59, and II, p. 209.

37 See Marcou's Geology of North America, p. 34, PI. V. Fig. 1.

38 See Paleontology of California, I, p. 63.

39 See Memoirs Am. Acad. Arts and Sciences, V (n. s.), p. 394.°

40 See Proc. Acad. Nat. Sci. Philad. for 1861, p. 317.

41 See Paleontology of California, I, p. 69, and II; p. 133.

42 See Proc. Bost. Soc. Nat. Hist., VIII, p. 192.

43 See Paleontology of California, I, p. 102, PI. XIX, Fig. 56.

44 See Paleontology of California, I, p. 135, PL XI, Fig. 93; also Jour. Acad. Nat. Sou 

Philad. (n. s.), IV, p. 392, PL LXVIII.Fig. 12.

(28)
WHITE. I COMPARISONS OF CERTAIN FOSSILS. 29 

TURRITELLA SERIATEtt-GRANULATA Eoemer.45

Mr. Gabb, in his Catalogue of the Cretaceous Fossils of California,46 

records this species, which was originally described from Texas, as 

among the fossils of the Shasta Group; but he gives neither description nor figure of the California shell.

TURRITELLA UVASANA Conrad.

This is one of the most common and characteristic species of the 

Tejon Group of California. In Vol. IV, United States Explorations and 

Surveys West of the One Hundredth Meridian, p. 195, pi. XVIII, figs. 

1, a and b, I identified a shell from the Cretaceous of Southern Utah 

with this species. I am now satisfied that this reference was not correct, and also that the Utah shell comes from quite a different horizon.

NUCULANA GABBI Conrad.

Gabb originally described and figured this shell from the Cretaceous 

of JS"ew Jersey, under the name of Leda protexta." The specific name 

being a synonym, Conrad changed it to gabbi, and placed it under Nuculana. Gabb referred a shell from his Martinez and Tejon Groups, in 

California, to this species.48 A comparison of Gabb's figures of the two 

forms (loc. cit.) will, I think, convince any one that they furnish no 

ground for the opinion that they are specifically identical.

GRYPHJSA YESICULARIS Lamarck.

Of this species Gabb says, in Paleontology of California, Vol. I, p. 

205: UA few small specimens of this species were picked up not in situ, 

near San Diego, by Dr. Cooper. It has not been found elsewhere on the 

west coast."

From the foregoing statements with regard to these fossils, it is plain 

that the identification which has been made of them is of too doubtful 

a character to base any generalizations upon it as to the equivalency of 

any of the California Cretaceous strata with any strata of that period in 

Central and Eastern North America. Perhaps, with our present limited 

knowledge of the subject, one would not be fully justified in saying positively that Mr. Gabb was wrong in all these identifications; but the proof < 

of identity is not satisfactory in the case of any of the species. That 

they are closely similar to the species to which he refers them is true, 

but satisfactory proof of such identity as would indicate the contemporaneous origin of the strata respectively containing them is certainly 

wanting.

46 See Kreidebildungen von Texas, p. 39, PI. IV, Fig. 12.

46 See Paleontology of California, II, p. 227.

.« See Jonr. AcUd. Nat. Sci. Philacl. (n. s.), IV, p. 803, PI. XLVIII, Fig. 23.

48 See Paleontology of California, I, p. 199, PI. XXVI, Fig. 185; also II, p. 250,
30 NOTES ON THE PALEONTOLOGY OF . CALIFORNIA. [BULL. 15.

ON THE SEPARATION OF CONTEMPORANEOUS CRETACEOUS FAUNAS 

IN WESTERN NORTH AMERICA.

Of the various conditions which limit the distribution of marine 

faunas, the intervention of land-barriers may be regarded as necessarily the most effective, and if such barriers are of great extent they 

may be well nigh absolute. And yet it is well known that certain 

fossil as well as living species of marine mollusks have reached an 

almost world-wide distribution, notwithstanding the intervention of 

great continental areas. Still, if in the course of the paleontological 

investigation of any region we find that certain formations in different parts of it which are presumably of the same geological age present a marked difference in the marine molluscan species which each 

formation respectively contains, it is natural to infer that those faunas, 

when living, were separated by a land barrier of considerable extent.

The facts which I have observed in Western North America indicate 

that such a barrier existed during the Mesozoic age in the form of a 

comparatively narrow continental belt, having a northward and southward trend, which then almost, if not quite, completely separated the 

respective marine faunas which, simultaneously existed upon either 

side. The former existence of a western continental area, which finally 

blended with the remainder of the continent, has long been recognized, 

and I shall not in this connection discuss its existence previous to the 

Cretaceous period further than to say that there are marked differences 

between the Carboniferous fauna of California and that of the great 

continental area to the eastward of the Pacific coast region. At the 

close of the Knoxville (probably Neocomian) epoch, the western edge 

of the continental area cannot have been far removed from its present 

position. At the beginning of the Chico epoch its western boundary 

was not further westward than the western base of the Sierra Nevada, 

and at the close of the Lower Cretaceous its eastern boundary was not 

further eastward than the eas.tern base of the Eocky Mountain Eange 

in Montana to the northward, and the western base of the Sierra Madre 

to the southward; that is, the Pacific coast Cretaceous strata now reach 

to the western base of the Sierra Nevada, while the Missouri Valley 

Cretaceous reaches as far west as the eastern base of the Eocky Mountains in Montana, and the Texas Cretaceous reaches as far west as the 

western base of the Sierra Madre in Mexico.

Since the faunas on each side of the site of that belt are distinctly 

different, although they are presumably of the same age, it seems 

necessary to infer that the belt was a very long one; otherwise the 

faunas might easily have become distributed around it. The eastern 

and western boundaries of the belt were no doubt irregular in trend, 

and the eastern one especially varied greatly from one epoch to another 

until all beyond to the eastward became a part of the present continent.

(30)
WHITE.] SEPARATION OF FAUNAS. 31

The trend of the western coast during the Chico epoch of the later 

Cretaceous was quite irregular, as shown by the localities at which its 

fossils have been found. As befdre intimated, it passed along the western base of the Sierra Nevada j then, sweeping around the northern end 

of the area which is now occupied by that mountain range, it extended 

into Eastern Oregon as far as longitude 120°, latitude 44°. This is the 

most easterly point at which fossils of the Chico Group have been found, 

and it is much further eastward than any point at which any other of 

the Pacific coast Cretaceous or of the T6jon deposits have been discovered. It thus appears that while the present site of the Sierra 

Nevada was within that continental belt during the Chico epoch, the 

Cascade Eange was then either submerged under the Pacific or was 

broken through by the entrance to a large gulf.

Again, the trend of the western border of that belt did not during 

the Cretaceous period coincide with the present trend of the Pacific 

coast to the southward. Such a trend would have thrown the site of the 

Sierra Madre of Mexico within or to the westward of the continental 

belt; whereas the existence of eastern Cretaceous deposits upon the 

western side of that range shows that its place was then in the Cretaceous sea, upon the eastern side of the belt. It is therefore probable that 

the peninsula of Lower California occupies the site of that portion of the 

belt which extended southward from the Sierra Nevada.

The bearing of these paleontological data upon the orography of 

Western North America is obvious; but it is not my present purpose 

to discuss that question, and I will close these remarks by rehearsing 

a few facts and indications which I think favor the views which I have 

advanced as to the extreme length and long continuance of the ancient 

continental belt of Western North America:

First, the fauna of the Knoxville beds of the Shasta Group extends 

from Alaska southward at least as far as Central California; second, 

some fossils which have been sent to the U. S. National Museum from 

Southern Mexico apparently come from strata of similar age; third, 

no rocks of the age of that group are known to exist to the eastward of 

probable site of that belt; fourth, the Jurassic fauna of the strata which 

lie to the eastward of the assumed site of the belt is entirely different 

from that of the reputed Jurassic strata to the westward of it.

CONCLUSIONS.

The conclusions which I have reached concerning the questions that 

are discussed on the foregoing pages may be summed up briefly as follows :

The strata which constitute the Tejon, Martinez, and Chico Groups

(31)
32 NOTES ON THE PALEONTOLOGY OF CALIFORNIA. I BULL. 15.

of Gabbjform one unbroken series, which I have called the Chico-Tejon 

series, ,and which rests unconformably upon all the rocks beneath it, 

and upon which the Miocene rests conformably. The Tejon portion of 

this series represents the Eocene, and the Chico portion the-closing 

epoch of the Cretaceous. But there is an alternate commingling of 

types throughout the whole series, so that no horizon can be designated 

which will sepparate all the Cretaceous types on the one hand and all 

the Tertiary types on the other. In other words, there is an unbroken 

faunal and strati graphical continuity from the Cretaceous to the Tertiary 

portion of the series.

The Shasta Group is separable into two divisions, which I have designated as the Knoxville beds and the Horsetown beds, respectively. 

The latter probably represent the age of the Gault of Europe, and the 

former apparently the age of the Lower Neocoinian, or strata upon the 

confines of the Jurassic. There.is probably a hiatus between these two 

divisions, such as is indicated by the last remark, although a small 

number of species appear to be common to both.

A small number of species also appear to be common to both the 

Chico Group and the Horsetown beds of the Shasta Group, although 

so wide a hiatus is indicated by the types of a large- part of their respective fossils, as already mentioned.

The Aucella erringtonii of the Auriferous Slates is, with considerable 

confidence, identified with the A. piocMi of the Knoxville beds of the 

Shasta Group. Therefore, those Auriferous Slates are regarded as of 

the same geological age as the Knoxville beds. It is true that this 

opinion is reached mainly upon the identification of one fossil species, 

but that species is one of the most persistent and widely distributed ones 

in the whole range of the geological series.

The Knoxville beds are regarded as having been synchronously deposited with those widely known Aucella-bearing strata which have 

been found at various points along the north west coast of "North America, and also as homotaxially equivalent with those which in Northern 

Europe and Asia bear the same species of Aucella.

No species of fossils yet found in the California Cretaceous rocks have 

been satisfactorily identified with any which occur in strata to the eastward of the Sierra Nevada.

This difference in the respective faunas which existed simultaneously 

at successive epochs is believed to have been due to the presence'of a 

comparatively narrow but long continental belt which existed in the 

region which now comprises that of the Pacific coast, continuously from 

a time at least as early as the earliest epoch of the Cretaceous period.

(32)
INDEX.

Pnge.

Aucella-bearing strata of California, geological age of........................ 26

Aucella concentica, probably existing in both Jurassic and Neocomian strata.. 26

Ajicella, geographical distribution of ...........t#............................ 23

. Auriferous slates, faunal relation to Shasta Group............................ 24

Becker, Dr. Q. F., studies of the New Idria series of strata.................... 13

! joint studies by the author and ....................................... 7

 on Cretaceous strata of Wallala...........................'.........J.. 27

 on nonconformity below the Chico..................................... 15

California fossils, assumed identification of, in'eastern strata ................. '27

Chico, Tejon series, the.......... ...................... ...................... 11

Conclusions................................................................. 22

Condon, Prof. Thomas, collections referred to ................................ 31

Conrad, Mr. T. A., publication referred to...................1................ 11

Cretaceous rocks of California, Whitney & Qabb's classification of ........... 9

Dall, W. H., Alaskan collections referred to.................................. 23

Doroschin, Peter, collections referred to........................ .,*............ 23

Eichwald, Prof. E. von, publication referred to............................... 23

Fischer, Dr. P., publication referred to....................................... 22

Gabb, William M., publications referred to................................... 9

General remarks ............................................................ 7

Griswold's, Miocene strata near. .............................................. 15

Heilprin, Prof. A., publication referred to .................................... 12

Horsetown beds............................................................. 19

Keyserling, Graf .von, views referred to ...................................... 26

Knoxville beds..--..--...... ................................................ 19

Lyell, Sir Charles, quoted.................................................... 16

Marcon, Prof. Jules, publication referred to ........................... -.. .... 12

 views of, referred to ..... ....... ......'...... .......................... 13

Mariposa estate, collections made upon....................................... 24

New Idria region, geology of ................................................ 13

Orcutt, Mr. C. K.; fossils collected near San Diego........................... 27

Orbigny, views referred to................................................... 26

Pavlow, Mr. A., views referred to............................................ 26

San Diego, Cretaceous fossils from........................................... 27

Separation of contemporaneous Cretaceous fauna ............................ 30

Shasta Group, The .......................................................... 18

Shasta Group; relations of, beyond the limits of California................... 22

Knoxville beds, list of fossils of......'...... ,\................................ 20

Trautschold, Professor, views of, referred to ............. .................... 26

Turner, Mr. H. W., collections referred to .................................... JL9

Vallecitos Canon, geology of................................. ................ 15

Wallala, Cretacfeous strata found at.......................................... 27

Western continental area.................................................... 30

Whiteaves, Mr. J. F., views referred to ...................................... 22

Whitney, Prof. J. D., referred to ............................................ 9

Bull. 15 3 (33) 33

O

N' O T IC HJ.

The, bulletins of the United States («eolo<;ie,:il Survey will be numbered in u eontiuUOUK H«rie» and will be bound in volumes of convenient size. 

This bulletin will be included in Volume III.