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Full text of "A brief general account of fossil fishes : the Triassic fishes of New Jersey"

Geological Survey of New Jersey 



FROM THE 



ANNUAL REPORT OF THE STATE GEOLOGIST 



FOR 



10O4 



A BRIEF 

GENERAL ACCOUNT 
OF FOSSIL FISHES 



THE TRIASSIC FISHES OF NEW JERSEY 



C. R. EASTMAN 



TRENTON, N. J. 
MacCrellish & Quigley, State Printers. 

1905 



% 



82^ 






PART L 



A Brief General Account of Fossil Fishes* 



The Triassic Fishes of New Jersey. 







By C. R. EASTMAN. 



(27) 



JAN 15 1988 

UBRARlt* 



A Brief General Account of Fossil Fishes. 



BY C. R. EASTMAN, HARVARD UNIVERSITY. 



SUMMARY. 



1. Province of palaeontology and its relations to other natural sciences. 

2. General notions of palseichthyology ; some generalizations resulting from 

its study. 

3. Geological time-scale. 

4. Introduction and succession of the class of fishes. 

5. Characteristic forms of fish life in the Devonian system. 

6. Geological history of Elasmobranchs, Lung-fishes and Ganoids. 

7. General nature of the Boonton Triassic fish fauna. 

8. Discussion of probable physical conditions and causes of destruction of 

fish life in the Newark beds. 

9. Brief survey of the progress of palseichthyology. 

10. Progress of our knowledge of American Triassic fishes. 

Province of Paleontology. — It having been suggested by the 
State Geologist that a presentation in untecbnical language of 
the leading facts brought to light by the study of fossil fishes of 
New Jersey, together with some statement of their relations to the 
science of palaeontology in general, would be of interest to a 
wide class of readers, the following section of the report has 
been prepared in accordance with that idea, detailed systematic 
descriptions being reserved for a separate chapter. Owing to 
the large number of persons whose attention has been attracted 
in one way or another to the remarkable fish remains found at 
Boonton and elsewhere, it is taken for granted that a lively 
interest exists in questions concerning their origin, their rela- 
tions to extinct and modern forms, and the conditions under 
which they met their death and became preserved in the rocks. 
These and kindred topics it is our purpose to examine into in the 
following pages. 

^29) 



30 ANNUAL REPORT OF 

Probably everyone has some notion of what is meant by the 
term fossil. Strictly defined, fossils include the remains or traces 
of plants and animals that have lived during former periods of 
the earth's history, and whose remains or other indications have 
become preserved in the rocks. By the process of petrifaction, as 
it is called, the hard parts of animal bodies, such as the shelly cov- 
ering of mollusks, crustaceans, echinoderms (sea-urchins, star- 
fish, etc. ) , or the internal skeleton of vertebrates, become replaced 
by mineral matter, all organic substances being converted into 
stone. Horney chitinous tissue undergoes a similar process ; and 
certain other substances, such as vegetable matter, feathers, and 
in rare instances animal integument, become carbonized. But 
almost invariably the soft parts of dead bodies suffer decomposi- 
tion either before or after burial in the preserving medium, thus 
leaving no traces in the rocks. It is only under exceptionally 
favorable circumstances that muscular fibre, dermal coverings, 
cartilage, or internal organs (such as the swim-bladder, walls 
of the intestinal canal, or egg-cases of cartilaginous fishes) have 
been preserved in recognizable condition. Nevertheless, con- 
ditions have sometimes permitted even the most delicate struc- 
tures, such as insects' wings and impressions of jelly-fishes, to 
become retained in the soft mud, which afterwards became 
solidified. Localities famous the world over for the beauty and 
delicacy of their fossil remains are the lithographic stone quarries 
of Bavaria and the department of Ain, France. An inquiry into 
the conditions under which these deposits were laid down sug- 
gests with much plausibility that they represent filled-in lagoons 
of coral atolls. 

It is worthy of remark that any investigation of fossil faunas 
takes into account all questions relating to the environment of 
the forms represented, the climatal and geographic conditions 
amidst which they flourished, their food, habits, migration, and 
genetic relations to other species. In a word, we have not only 
to* consider the nature of organic remains which have become 
preserved in the fossil state, but must also reconstruct as ac- 
curately as possible the conditions that were operative during 
their lifetime, approaching them in the same manner as we would 
organisms of the present day. There is, therefore, no' essential 



THE STATE GEOLOGIST. 31 

difference between zoology and palaeontology, it being evident, 
as Huxley has said, that "fossils are only animals and plants 
which have been dead rather longer than those that died yester- 
day." In the same way, palaeichthyology, or that branch of nat- 
ural science which treats of fossil fishes, extends our information 
from the existing fauna back to the earliest advent of vertebrate 
life upon our globe, and furnishes important information concern- 
ing the mode of succession and evolution of one of the great 
classes of back-boned creatures, the ground-type of that remark- 
able sequence of forms whose culmination is man. 

Right at the outset we are brought face to face with the all- 
important and all-pervading doctrine of evolution, which forces 
upon us the truth that man is an organism amongst organisms, 
his origin and history being in nowise disassociated from the 
origin and history of other living creatures in the world. Let 
us once appreciate the intense human interest in the study of 
organic creation, once recognize the fact that geology reveals 
an elaborate history of organisms that have successively popu- 
lated the earth from the time life first began, and it is clear that 
we enter upon a most fascinating field for research. Stripping 
palaeontology of its more technical aspects, and looking upon it 
in a broad way as part of universal history, the foremost question 
we should seek to answer is, what general principles or laws are 
revealed by this history? Having ascertained what these laws 
are, we have next to interpret them philosophically, to ascertain 
the underlying cause or causes to which they are attributable. 
Do they of themselves afford a satisfactory summing up of the 
operation of natural processes which have always been at work 
in the world, and have the latter merely happened to behave in 
this manner — fortuitously, rather than in some other manner — • 
or do they suggest a teleological explanation, in that they reflect 
the presence of ulterior plan and design? 

In respect to* these fundamental problems, palaeontology vastly 
enlarges the material at our disposal for philosophical analysis, 
furnishing at the same time a most important aid and ally to 
cognate sciences like zoology and embryology ; and the extent to 
which these sciences severally supplement one another is indeed 
remarkable. A word may be said to illustrate the truth of this 



32 ANNUAL REPORT OF 

statement. Let us imagine the evidence of fossils to be excluded ; 
and let the zoologist, whom we may suppose is acquainted only 
with the modern fauna, be required to frame a theory of evolu- 
tion. He will at once perceive that animals belonging to- certain 
groups resemble one another more or less closely, but the groups 
themselves are widely separated; and, moreover, in some of them 
there exist wide gaps without any hint that they were ever filled 
or bridged over by intermediate forms. Holding in his grasp 
merely the ends of disconnected threads, how is the zoologist to 
prove their continuity, how demonstrate that they have all di- 
verged from a common strand ? Is it not equally logical for him 
to maintain, under the assumed limitations, the doctrine of 
special creation, and deny that the most extreme types of varia- 
tion are linked by common ancestry? 

All the way from a quarter to half a century ago, before 
palaeontology had made its great strides in advance, the con- 
ditions we have imagined were altogether real, and the lacunae 
between genera, families and higher groups presented a diffi- 
culty which it appeared unreasonable to explain by an appeal 
to- the imperfection of the palseontological record. On the one 
hand the doctrine of evolution required these gaps to be filled, 
on the other no< evidence was forthcoming to' show that they 
ever had been filled. An interesting anecdote is related of the 
elder Agassiz by one of his students, Professor A. S. Packard, 1 
which illustrates the attitude or the great naturalist toward 
evolution in his latter years. At the close of a lecture on 
Umulus, the horseshoe crab, in which Agassiz advocated the 
view that it does not stand as an isolated form in creation, but 
is descended from the common stem of jointed animals, the mas- 
ter strode up and down in a state of evident excitement, and 
then, as Packard recalls, "remarked to us with one of his most 
genial smiles on his lips : 'I should have been a great fellow for 
evolution if it had not been for the breaks in the palseontological 
record.' We replied : 'But, Professor, see what great gaps have 
been filled by the recent discoveries of birds with teeth, and of 
Tertiary mammals connecting widely separated existing orders.' 



1 Amer. Nat, vol. xxxii (1898), p. 164. 



THE STATE GEOLOGIST. 33 

And then, with a few more words, which we do not distinctly 
remember, we separated. * * * And so it is, in youth the 
older naturalists of the present generation were taught the doc- 
trine of creation by sudden, cataclysmic, mechanical 'creative' 
acts; and those to whose lot it fell to come in contact with the 
ultimate facts and principles of the new biology had to unlearn 
this view, and gradually to work out a larger, more profound, 
wider-reaching, and more philosophic conception of creation." 

One of the chief merits of palaeontology is that it has within 
recent years brought to light a wealth of facts which establish 
beyond dispute the continuity of life; and reveal, often in most 
circumstantial manner, how modern forms have been derived 
from antecedent forms, thus pointing to the conclusion that all 
animals and plants have sprung from a few primitive common 
ancestors. Though now all but universally accepted, the doctrine 
of evolution has been long in gaining ascendancy over the minds 
of men, and we are unable to declare that the newer views are 
at variance with the time-honored teleological explanation. Any- 
one who has read the late Professor Joseph Le Conte's "Evolu- 
tion in Relation to Religious Thought," or Huxley's "Scientific 
Essays," or similar works, must have been convinced that the 
evolutionary hypothesis strengthens rather than weakens the claim 
that the workings of Nature are but the expression of a divine 
intelligence. There are those who maintain it is unnecessary to 
conjure up a dens ex machina to explain physical processes; and 
opposed to these there are others, rather in the majority we think, 
who declare that the whole system would be unintelligible with- 
out purposeful design — hence the assertion that the present order 
of things has come about as the result of hazard is contrary to 
our senses. 

Palaeontology may not hope to answer such vital and far-reach- 
ing questions as these; and yet it is not vain to' expect from it 
light concerning the nature of the problems involved, and con- 
cerning our manner of viewing them. A very learned,- very high- 
minded, very reverent palaeontologist, for many years President 
of one of the sections of the French Academy, has thus apos- 
trophized the sources of our information in regard to creation : 
"We cannot refrain from looking with curious admiration upon 
3 GE01, 



34 ANNUAL REPORT OF 

the innumerable creatures that have become preserved to us 
from earth's early days, and calling them to life again in our im- 
agination. We interrogate these ancient inhabitants of the earth 
whence they were derived : 'Speak to us and say whether you 
are isolated remnants, disseminated here and there throughout 
the immensity of the ages, without an order more comprehensible 
to us than the scattering of flowers over the prairie? Or are 
you in verity linked one to another, so that we may yet be able, 
amid the diversity of nature, to discover indications of a plan 
wherein the Infinite has stamped the impression of his unity T 
The unraveling, of the plan of creation, this is the goal toward 
which our efforts aspire nowadays." 1 

General Notions of Pakvichthyology. — If this cursory review 
of the scope and province of palaeontology has shown us anything, 
it must convince us that fossils are to be regarded as precious and 
authentic historical documents, which, in so far as they 
reveal important truths of nature, have vastly widened our com- 
prehension of the organic world, and materially assist us in arriv- 
ing at a unification of truth. What is true of fossils in general 
is true in particular degrees of fossil fishes, which we have now 
to consider somewhat more fully. Enough has already been said 
to< show that the history of the group of fishes, the most primitive 
and most ancient of the vertebrate phylum, is of fascinating inter- 



1 Gaudry, A., Les Enchainements du monde animal, etc., p. 3. Paris, 1883. 

The continuation of this striking passage we shall do better to give in its- 
original choice diction, as follows : 

" Les paleontologistes ne sont pas d' accord sur la maniere dont ce plan a 
ete realise ; plusieurs, considerant les nombreuses lacunes qui existent encore 
dans la serie des etres, croient a 1' independance des especes, et admettent que 
l'Auteur du monde a fait apparaitre tour a tour les plantes et les animaux des 
temps geologiques de maniere a simuler la filiation qui est dans sa pensee; d* 
autres savants, frappes au contraire de la rapidite avec laquelle les lacunes 
diminuent, supposent que la filiation a ete realisee materiellement, et que Dieu 
a produit les etres des diverses epoques en les tirant de ceux qui les avaient 
precedes. Cette derniere hypothese est celle que je prefere; mais, qu' on 
1' adopte ou qu' on ne 1' adopte pas, ce qui me parait bien certain, c' est qu' il y 
a eu un plan. Un jour viendra sans doute ou les paleontologistes pourront 
saisir le plan qui a preside au developpement de la vie. Ce sera la un beau 
jour pour eux, car, s' il y a tant de magnificence dans les details de la nature, 
il ne doit pas y en avoir moins dans leur agencement general." 



THE STATE GEOLOGIST. 35 

est. Apart from its intrinsic interest, the study of fossil fishes 
deserves a high place in our esteem on account of its having re- 
vealed certain fundamental truths, the importance of which can- 
scarcely be overestimated. One of the most far-reaching of these 
in its later application is Louis Agassiz's discovery of the analogy 
between embryological phases of recent fishes and the geological 
succession of the class, which led him to a well defined conception 
of what is commonly .called the "biogenetic law" : The history 
of the. individual is but the epitomised history of the race. In thus 
introducing the element of succession in time, Agassiz laid the 
basis for all more recent embryological work. 

Another notable achievement arising from Agassiz's study of 
fossil fishes was the recognition of so-called "embryonic," "pro- 
phetic" or "synthetic" types, or such as combine in their structure 
peculiarities which afterwards became distributed amongst dif- 
ferent distinct types, and are never again recombined. Differ- 
ences in the organization of fossil fishes led Agassiz to discrim- 
inate between "lower" and "higher" forms, identical with the 
generalized and more highly specialized types of modern zoolo- 
gists. In the same way, Agassiz's "embryonic types," which he 
held to "represent in their whole organization early stages of the 
growth of higher representatives of the same type," are in many 
cases the ancestral types of the modern evolutionist. 

A single illustration must suffice to show the application of 
these important generalizations derived from the study of fossil 
fishes. Agassiz, in the initial volume of his famous P'oissons 
Fossiles, remarks more than once upon the fact that all fishes 
antedating the Lias have the extremity of the vertebral column 
deflected upward into a more or less prolonged caudal lobe, a 
condition technically described as heterocercal. Subsequently he 
observed that modern fishes exhibit a similar condition in their 
early stages, though it was left for the younger Agassiz to demon- 
strate that they faithfully reproduce ancestral characteristics,. 
Adverting to this matter in his well-known "Essay on Classifica- 
tion," Professor Agassiz remarks : "In my researches upon fossil 
fishes, I have pointed out at length the embryonic character of 
the oldest fishes, but much remains to be done in that direction. 
The only fact of importance I have learned of late is that the 



36 ANNUAL REPORT OF 

young Lepidosteus, long after it has been hatched, exhibits in the 
form of its tail, characters thus far only known among the fossil 
fishes of the Devonian system." * 

Still more suggestive was the same author's comment upon the 
remarkable resemblance between the human fcetus in an early 
embryonic stage and those of the shark and skate; the similarity 
being so obvious that it may properly be claimed for higher ani- 
mals, including man, that they pass through a "fish-stage," in 
which even gills and a rudimentary tail are present during the 
course of their early development. 

It is hoped that the above general observations will serve to 
help the reader to a more or less definite idea concerning the scope 
and aims of palaeontology, and the important influence exerted 
by it upon other lines of inquiry. Coming now more par- 
ticularly to the question of fossil fishes, it remains to sketch 
in outline the general history of this class of vertebrates so far 
as it is revealed to us by the palaeontological record, and finally to 
discuss the relations of those fishes occurring in the Triassic rocks 
of New Jersey to others that have preceded and followed them 
during the course of geological time. First of all, it is necessary 
to fix in our minds the chief divisions of the geological time 
scale, in order that the chronological succession of fossil forms 
may be kept clearly in view, and that we majr form a more ade- 
quate appreciation of the time-interval between the Triassic fishes 
of New Jersey, and the Palaeozoic, let us say, of adjoining States. 

Geological Time Scale. — Most persons are probably aware that 
geologists divide the fossiliferous rocks into three principal series, 
known respectively as Primary, Secondary and Tertiary, or more 
familiarly as Palaeozoic, Mesozoic and Cenozoic — these latter 
terms signifying "Ancient Life," "Mediaeval Life" and "Recent 
Life." The term Archaean or Archaeozoic is applied to primitive 
rocks of great thickness underlying the lowermost Palaeozoic, 
none of which exhibit satisfactory evidence of organic life; if 
they formerly contained fossils, these have become entirely oblit- 
erated by metamorphic processes. The principal time-relations, 
"eras" or "ages," as they are called, are subdivided into various 



1 Contributions to the Natural History of the United States of America, vol. 
I. (1857), p. US- 



THE STATE GEOLOGIST. 



37 



"systems" which are accepted everywhere as standard units of 
chronology; and the systems are further subdivided into ''periods" 
and "epochs.'' It is important to observe the distinction between 
the historical categories expressing time-relations, and the cor- 
responding division of the solid rocks into systems, series and 
groups. The stratigraphical column, that is to say, the entire 
rock series, is divided by means of unconformity and character 
of the fossils into "systems," as already observed, and these are 
in turn divided into series, groups and formations. The corre- 
spondence between this dual historical and stratigraphical class- 
ification is exhibited bv the following: schedule : 



TIME. 


ROCKS. 


Eras 
Ages 
Periods 
Epochs 


> Systems 

Series 
Groups 



For convenience of reference we may also be permitted to insert 
here a table showing the principal subdivisions of the strati- 
graphical column : 



38 



ANNUAL REPORT OF 



ERAS 


SYSTEMS 


PERIODS 


LIFE 


Quaternary 


Pleistocene 


Man 


Cenozoic 


■ 
Tertiary 


Pliocene 
Miocene 
Oligocene 
Eocene 


Mammals the dominant class 


Mesozoic 


Cretaceous 

Jurassic 

Triassic 




Reptiles dominant 
Birds appear 
Earliest mammals 


Palceozoic 


Permian 

Carboniferous 

Devonian 

Silurian 

Ordovician 

Cambrian 


j Upper 
\ Lower 
( Upper 
•] Middle 
( Lower 


Amphibians the dominant 
class 

Fishes dominant 

Invertebrates still dominant 

Fishes appear 

All classes of invertebrates 


Archczozoic 


Algonkian 
Archaean 


Huronian 
Laurentian 


Indistinct evidence of life 
No evidence of life 



Introduction and Succession of the Class of Fishes. — We may 
now proceed to take a brief survey of the introduction and prog- 
ress of the class of fishes, as revealed to us by palseontological evi- 
dence, after which we shall be better prepared to understand the 
relations born by our local fossils to- the group as a whole. It 
requires but a limited exercise of the imagination to picture to 
ourselves a world essentially like the one we inhabit to-day, but 
warmer, and tenanted only by lower groups of organisms; the 
land mostly in the form of scattered islands, destitute of grasses, 
deciduous trees and flowering plants, untrodden by any verte- 
brate creature ; the sea without aquatic mammals, reptiles, fishes ; 



THE STATE GEOLOGIST. 39 

and the highest types of animal life consisting of forms related 
to the scorpion and king-crab. "Monsters in those days" there 
were none; life, such as it was, existed in profusion, but was of 
decidedly inferior organization, sluggish or sessile, mostly of 
small size, and rather uniformly distributed. But already, at as 
far distant a period as the oldest fossiliferous horizon, differentia- 
tion had been taking place, and all the great divisions of inverte- 
brates had become definitely established. Finally it came to 1 pass, 
in some manner and at some epoch — how and when we know not 
for certain — that the earliest chordate animals were introduced; 
that is to say, animals ancestral to' modern vertebrates, probably 
cartilaginous and with only dermal folds for limbs, but craniate, 
and having an axial skeleton. 

Some have imagined that the transition from invertebrates to 
chordates occurred through annelid worms, others through 
jointed animals (Arthropods), but here at least is a great gap as 
yet unfilled. All that we can affirm is that the Cambrian system 
has yielded hitherto no trace of forms which one may regard as 
standing in ancestral relations to* chordates, and it is not until the 
Ordovician (or Lower Silurian) that we first meet with such 
creatures in the reality. These primitive, weird-looking organ- 
isms differ from fishes proper, and likewise from all other verte- 
brates, in the absence of paired limbs and of a lower jaw, as well 
as in the microscopical structure of their hard parts. Under the 
name of Ostracophores (literally "shell-bearing"), Professor 
Cope has placed them in a distinct class (Agnatha) , thus sharply 
separating them from fishes proper. Nevertheless they approach 
in other respects very closely to fishes, and when we remember 
that the great group of Elasmobranchs (sharks and rays) has 
equally remote an origin, it will be clear that the history of verte- 
brate life on our globe extends over incredibly long periods of 
time. 

One of the best known of these primitive vertebrates is that 
curious form to which Agassiz has given the name of Pterichthys, 
familiar to all readers of Hugh Miller's fascinating works. The 
first impression produced by these bizarre creatures upon the 
mind of their discoverer has been graphically described both by 
Miller and Agassiz. Says the latter: "This remarkable animal 



40 ANNUAL REPORT OF 

has less resemblance than any other fossil of the Old Red Sand- 
stone to< anything that now exists. When first brought to view 
by the single blow of a hammer, there appeared on a ground of 
light-colored limestone [i. e., sandstone] , the effigy of a creature, 
fashioned apparently out of jet, with a body covered with plates, 
two powerful-looking arms articulated at the shoulders, a head 
as entirely lost in the trunk as that of the ray (or skate), and a 
long angular tail, equal in length to' a third of the entire figure." * 

Elsewhere when commenting on the singular fish fauna of the 
Old Red Sandstone he remarks : "I can never forget the impres- 
sion produced upon me by the sight of these creatures, furnished 
with appendages resembling wings, yet belonging, as I had satis- 
fied myself, to the class of fishes. * * * It is impossible to see 
aught more bizarre in all creation than the genus Pterichthys ; the 
same astonishment felt by Cuvier in examining Plesiosaurs, I 
myself experienced when Mr. H. Miller, the first discoverer of 
these fossils, showed me the specimens which he collected in the 
Old Red Sandstone of Cromarty." 

The genus Pterichthys (Fig. i) is not represented in the rocks 
of this country, although a closely related form, BothHolepis, 




Pterichthys testudinarius Ag. Lower Old Red Sandstone; Scotland. Lat- 
eral aspect, restored by Dr. R. H. Traquair. X ^2- 

occurs in the Devonian of eastern North America and in Color- 
ado. Other most curious and ancient Ostracophores are the 
forms known as Cephalaspis (Fig. 2), Pteraspis (Fig. 3) and 



1 Introduction to Hugh Miller's "Footprints of the Creator," p. xxi. Amer- 
ican edition (Boston), 1850. 



THE STATE GEOLOGIST. 



41 




Pig. 2. 

Cephalaspis murchisoni Egert. Silurian and Lower Devonian; Hereford- 
shire. Lateral aspect, restored by Dr. A. S. Woodward. X %• 




Fig- 3- 

Pteraspis rosirata Ag. Lower Old Red Sandstone; Great Britain, 
view of partially restored fish. X Z A- 



Side 



TremataspiSj together with the remarkable forms described with- 
in recent years from the Scottish Silurian, grouped by Dr. Tra- 
quair under the name of Anaspida. Of the above mentioned 
forms, only the genus Cephalaspis appears to have been common 
to both Europe and America. 

Another primitive group of organisms found in association 
with Ostracophores in the Devonian of various parts of the 
world, and by many regarded as more or less akin to them, has 
received the name of Arthrodires, in allusion to a curious hinge- 
like device by which the body armor is movably united with the 
head-shield. Arthrodires are heavily armored fish-like verte- 
brates, the head and forward portion of the body being encased 
in a system of dermal plates, usually ornamented with fine stellate 
tubercles, and with cartilaginous axial skeleton. No indications 
have been found of paired fins, properly speaking, but a lower 
jaw occurs, suspended freely in the soft parts without being artic- 
ulated to the cranium. 

The typical genus is Coccosteus (Fig. 4), a comparatively small 
form, common to both sides of the Atlantic, and ancestral to the 



42 ANNUAL REPORT OF 




Fig. 4. 

Coccosteus decipiens Ag. Lower Old Red Sandstone; Scotland. Lateral 
aspect, restored by Dr. R. H. Traquair. X J A- 

hugest of all Palaeozoic fishes, Dinichthys and Titanichthys, 
which occur in the uppermost Devonian of Ohio and neighboring 
States. The length of these creatures has been estimated at 
upwards of fifteen or twenty feet, and the solidity of their armor- 
plating has never been surpassed amongst fishes. Over the back 
and head the bones were in places fully three inches thick, and 
exceedingly dense, though in smaller forms, of course, the arm- 
oring was lighter. Equally effective was their dental armature, 
Dinichthys having in the upper jaw a pair of beak-like incisors, 
behind which were formidable shear-teeth; and in the lower jaw 
a large and exceedingly powerful dental plate, likewise provided 
with a beak-like projection in front. It is evident that these 
creatures could not have been very mobile, owing to their cum- 
bersome armor and lateral expanse of body, Titanichthys having 
a total width of about six feet; and it is further obvious from 
the character of sediments that they frequented the mouths of 
shallow estuaries, where they maintained probably a not very 
active existence. The characters already enumerated, such as the 
peculiar dermal plating, cartilaginous axis, and non-articulation 
of the lower jaw with the cranium, separate Arthrodires widely 
from modern bony fishes. 

Considerable numbers of these armored creatures nourished 
throughout the Devonian, but became extinct at the close of that 
period without leaving any descendants. It is worth while to 
take note, in passing, of these and similar instances of extinction, 
which have in times past affected not only species and genera, 
but entire groups of organisms, sometimes without any discernible 
cause! N0 1 doubt in the majority of cases large groups become 
crowded out through the incessant and relentless struggle for 



THE STATE GEOLOGIST. 43 

existence, weaker, less active, and less suitably adapted creatures 
.giving way before their more successful competitors. It is a 
general rule, also, that overspecialized forms, or those whose 
habits and organization have responded so as to' conform to par- 
ticular external conditions, are liable to perish when these condi- 
tions change, through inability to readjust themselves in some 
other direction. But it would appear, further, that races of ani- 
mals have a life-period of their own, comparable to those of in- 
dividuals, or the nations of mankind. Just as the history of the 
latter resolves itself into periods of early development, dominant 
culmination — or "Bliithezeit" as the Germans call it — and final 
decadence; so species, genera and larger groups may be said to 
pass through various stages of immaturity, maturity and senility. 
Amongst old-age characteristics, whether of the individual or 
the race, must be reckoned an increased incapacity for variation, 
or decay of evolutional vigor; and after a certain point has been 
reached, this road leads on to extermination, either sudden or 
long-postponed. We shall have occasion to' observe presently 
that there is a wide difference in longevity amongst various groups 
of organisms. 

It will aid us to a graphic conception of the processes of evolu- 
tion by likening them to a body rotating not always with uniform 
velocity in an ascending spiral, and giving off particles which par- 
take of its own motion. At irregular intervals the centrifugal 
force is great enough to cause the particles to fly off in all direc- 
tions, thus giving rise to what is known in palaeontology as "ex- 
pression points." 1 Now these particles, which we may call 



1 The following definition of expression points is taken from Smith Wood- 
ward's "Outlines of Vertebrate Palaeontology" (Introduction, p. xxi.) : 

"All known facts appear to suggest that the processes of evolution have not 
operated in a gradual and uniform manner, but there has been a certain 
amount of rhythm in the course. A dominant old race at the beginning of its 
greatest vigor seems to give origin to a new type showing some fundamental 
change; this advanced form then seems to be driven from all the areas where 
the dominant ancestral race reigns supreme and evolution in the latter becomes 
comparatively insignificant. Meanwhile the banished type has acquired great 
developmental energy, and finally it spreads over every habitable region, re- 
placing the effete race which originally produced it. Another 'expression 
point' (to use Cope's apt term) is thus reached, and the phenomenon is re- 
peated. The actinoptergian fishes furnish an interesting illustration. The 



44 ANNUAL REPORT OF 

variants, may be supposed to throw off in turn smaller particles, 
corresponding to species, which radiate in the same manner. 
Some will be precipitated at tangential extremes, halting finally 
when resistance overcomes their momentum; others will strike 
downwards in a retrograde path, and shortly disappear — these 
being the so-called degenerate species. And still others will be 
given an impetus in an upward direction, their movement contin- 
uing until they too> are overcome by resistance. These last are 
the progressive species, and it is evident that only amongst this 
class can any persist and keep pace with fresh competitors that 
are constantly entering the field at higher levels. Certain ones 
that persist longer than others thus come toi stand out in the 
changing- complex as archaic types, their antique characters con- 
trasting strangely with the remodeled order O'f things. 

The parallelism we have imagined is, not exact, but may serve 
as a graphic portrayal of the manner of succession and decadence 
of species and higher groups. One meets with a closer analogy 
in studying the history of languages, or of individual words in 
a single or in various languages. Every one knows that certain 
primitive roots, especially designations of essential objects and 
relations, have survived from early Aryan speech down to mod- 
ern times; and innumerable cognate expressions exist side by side 
in European tongues derived from the Latin and Greek. Roots 
and stems, that is to say, the ground types, persist practically 
unchanged throughout all the vicissitudes and changing condi- 
tions of human progress. Variations, too, once firmly estab- 
lished, and favored by environment, are apt to persist indefinitely. 
Not only do words, idioms and figures of speech all illustrate the 
principle of evolution, but standards of pronunciation furnish 



earliest known member of this order (Cheirolepis) appears as an insignificant 
item in the Lower Devonian fauna, where crossopterygian and dipnoan fishes 
are dominant. When the latter begin to decline in the Lower Carboniferous, 
the suborder to which Cheirolepis belongs (Chondrostei) suddenly appears in 
overwhelming variety. By the period of the Upper Permian another funda- 
mental advance has taken place — the Protospondyli have arisen; but only a 
solitary genus is observed among the hosts of the dominant race. In the Trias 
the new type becomes supreme, and at the same time the next higher suborder, 
that of the Isospondyli, begins to appear. This lingers on in the midst of the 
dominant Protospondyli during the Jurassic period, and then in the Cretaceous 
this and still higher suborders suddenly replace the earlier types and inaugu- 
rate a race which has subsequently changed only to an insignificant extent." 



THE STATE GEOLOGIST. 45 

excellent examples of the working of the same governing force. 
Some of these are sufficiently significant as to be worth noting. 

As has been aptly remarked by Professor Lounsbury, 1 the 
survival of ancient usage explains the existence among the unedu- 
cated of many pronunciations which, at a former period, were 
regularly employed by the educated. "The language of the illit- 
erate is," this author observes, "to> a great extent, archaic. It 
retains words and meanings and grammatical constructions which 
were once in the best of use, but have ceased to be used by the 
best. This is as true of pronunciation as it is of vocabulary and 
grammar. In this respect the archaic nature of the speech of the 
uneducated manifests itself in practices which would be little ex- 
pected to exist. It sometimes affects the place of the accent. In 
our tongue it is generally popular usage which is disposed to i lay 
the stress upon a syllable far from the end of the word. * * * 
Yet, curiously enough, this practice, based upon classical author- 
ity, lingers sometimes in the mouths of the uncultivated long after 
it has been abandoned by the cultivated. Readers of Milton are 
well aware that with him blasphemous is invariably pronounced 
blasphe' -mous . It was probably the general usage of the educated 
men of his time. Now no one pronounces it so 1 save the unlet- 
tered. They remain faithful to the classical quantity, and are 
treated with contumely for it by such as deem it both their right 
and duty to be horrified by hearing illustrate pronounced 
illustrate. Similar observations may be made of contrary and 
mischievous." 

It is apt to provoke a smile on hearing familiar words pro- 
nounced as if spelled critter, nater, picter, etc., instead of sounding 
the final ture, yet these are instances of inherited usage which 
two or three centuries ago was common in good society. A Lon- 
doner's pronunciation of the word clerk is another interesting 
survival, as is also the custom of replacing the sound of e by a 
in words like certain (vulgarly sartin), service, servant, sermon 
and serpent. Even Jersey was once pronounced Jarsey, as clergy 
was pronounced clargy. The reader will not fail to notice the 
close parallel existing between these cases of survival of ancient 



^he Standard of Pronounciation in English (New York and London, 1904). 



46 ANNUAL REPORT OF 

mannerisms and the persistence of archaic types of animal life. 
The analogy may be developed a little further. 

A tendency is to be noted nowadays toward accommodating 
the spoken word to the written, that is to- say, there is purposeful 
adaptation along definite lines. This tendency is adverted to by 
Professor Lounsbury in following wise : "Colloquial or provin- 
cial speech will long continue to retain the old pronunciation. 
But even in those quarters they tend to die out with the increase 
of the habit of reading and the steadily waxing influence of the 
schoolmaster. Furthermore, in most, if not in all, of the instances 
where anomalies now exist, or once existed, it will be found that 
the current pronunciation represents a form of the word which 
at some time or at some place prevailed in writing as well as in 
sepaking. Illustrations of this are frequent. As good a one as 
any is furnished by the name itself of our language. We spell it 
Enghsh; we pronounce it Ing'glish; and we pronounce it so be- 
cause by many it was once so spelled." And finally it is to> be 
observed that all language is full of what Trench very happily 
calls the "fossil remains of metaphors" — that is to say, words 
which were once used to convey ideas by comparing them to 
something known, but the figurative sense of which is now for- 
gotten. Examples of this kind will occur to' the minds of every 
reader. 

The object of the digression we have just made has been to 
bring the reader directly in contact with some of the fundamental 
facts with which palaeontology has to- deal, and to aid him to< an 
understanding of them, or of their significance, through analogous 
examples. Returning now to our main theme, we may say finally 
of the Ostracophores and Arthrodires that they stand for diver- 
gent groups which branched off at a remote date from the parent 
stock, but failed to maintain their own as against later derivatives 
of the same stem. In the end their fate was identical, and, which 
is the more surprising, nearly contemporaneous with that of domi- 
nant groups of invertebrates during the Palaeozoic, such as Trilo- 
bites and Eurypterids. 

Blasmobranchs. — We have now to consider another very an- 
cient, very primitive and very conservative group of fishes, one 
which has retained the essential features of its organization prac- 



THE STATE GEOLOGIST. 47 

tically unchanged from the Silurian down to the present day. 
This is the great subclass of cartilaginous fishes, or Elasmo- 
branchs ( chimasroids, sharks and rays), by many supposed to be 
the ancestral stem from which all modern fishes have been derived, 
or at least which may be looked upon as representing most nearly 
the persistent ancestral condition of fishes. Amongst the salient 
characteristics of Elasmobranchs, by which they may be distin- 
guished at once from all modern fishes, are to' be noted ( 1 ) their 
cartilaginous skeleton; (2) shagreen integument; (3) heterocer- 
cal (asymmetrical) tail; (4) separate, slit-like gill-openings, 
metamerally arranged; (5) clasping organs in the male, and (6) 
various internal peculiarities. The skeleton is cartilaginous, 
sometimes calcified to a considerable extent, but never ossified, 
and never with dermal bones. The sturgeon is one of the few 
existing fishes which also has a cartilaginous skeleton and het- 
erocercal tail — that is to say, one with a much produced superior 
lobe, instead of having the upper and lower lobes about equal; 
but it differs in its remaining characters, such as the absence of 
shagreen, of slit-like gills, presence of dermal bones, etc. Even 
a superficial examination of any shark or ray must serve to con- 
vince one that the characters enumerated above, taken in their 
entirety, are very trenchant, but there are numerous others besides 
these. For very full and minute accounts of the structure and 
habits of Elasmobranchs, it will be necessary to' consult standard 
works on ichthyology, such as Dr. Gunther's "Introduction to the 
Study of Fishes," the volume on Fishes in the "Cambridge Nat- 
ural History," or Bashford Dean's "Fishes, Living and Fossil." 
The following general remarks, taken from the second of the 
works just mentioned, must suffice for the present discussion. 

"The Elasmobranchs are for the most part active predaceous 
fishes, living at different depths in the sea, from the surface to 
nearly a thousand fathoms, and ranging from mid-ocean to i the 
shallower waters round the coasts in almost every part of the 
world. Although typically marine, they sometimes ascend rivers 
beyond the reach of tides, and a few are permanent inhabitants 
of fresh water. They are most abundant in tropical and sub- 
tropical areas, where they also attain their greatest size, and are 
numerous in temperate regions, but there are some species which 



48 ANNUAL REPORT OF 

are typically Arctic. None of them are small, and some of the 
sharks are the largest of living fishes. All are carniverous, but so 
diversified is their food that in different species it may range from 
other fishes of no mean size to mollusks, crustaceans and other 
invertebrates, or even to plankton. In their breeding habits the 
sharks and dog-fishes present many interesting features. * * * 
The majority of the sharks, dog-fishes and rays are viviparous, 
that is, the young are born alive ; the rest * * * are ovipa- 
rous, that is, the young are hatched out after the extrusion of 
the eggs." 

Fossil remains of Elasmobranchs in the shape of detached hard 
parts, such as teeth, fin-spines and dermal tubercles, are known 
from a few Silurian localities, and are therefore amongst the 
earliest undoubted indications of vertebrate life. Fragments of 
this description become more numerous in the Devonian, and in 
the uppermost horizons of the system are found magnificently 
preserved skeletons, which exhibit in some instances even the 
microscopic structure of muscular tissues. 1 




Pig. 5- 

Cladoselache fyleri Newb. Cleveland Shale (Upper Devonian) ; Ohio. Lat- 
eral aspect, anterior dorsal fin-spine omitted. X V20. (From Dean.) 

The best known of these primitive sharks is Cladoselache (Fig. 
5), from .the Cleveland shale of Ohio, an elongated, round- 
bodied form attaining a length of about five feet, with two^ dorsal 
fins and a very remarkable caudal extremity. The structure of 
the paired fins is extremely interesting in that it enlightens us 
as to the probable origin of vertebrate limbs from continuous 
dermal folds on either side of the body, just as the dorsal, caudal 
and anal fins are presumably derived from a continuous median 
fold. The teeth of Cladoselache are in the form of sharply 



1 Dean, B., Preservation of Muscle-fibres in Sharks of the Cleveland Shale. 
Amer. Geol., vol. xxx. (1902), pp. 273-278. 



THE STATE GEOLOGIST. 



49 



pointed cusps adapted for piercing, and the anterior dorsal fin 
appears to have been armed with a powerful spine similar to those 
described under the name of Ctenacanthus. This Devonian genus, 
as has been said, is the most primitive type of Elasmobranch yet 
discovered, and is regarded as the ancestral form from which a 
host of Carboniferous and most modern sharks are derived. A 
curious form intermediate between sharks and rays (Tamiobatis) 
is also known from the Devonian ; and if we may assume dental 
plates to furnish a reliable clue, chimaeroids (Ptyctodus) were 
present throughout this system in astonishing abundance. 

During the Carboniferous the group of Elasmobranchs in- 
creased prodigiously in point of numbers, size and variety, and 
attained a world-wide distribution, but their rapid culmination 
which took place at the opening of this era was followed toward 
its close by an equally notable decline, approaching almost to the 
verge of extinction during the Permian. Some of the Carbonifer- 
ous sharks were formidably armed, the largest fin-spines and most 
powerful crushing, cutting and piercing- teeth known to the science 
of ichthyology having been developed during this era. An inter- 
esting generalized shark from the French Coal Measures {Pleura- 
canthus) combines within itself such a variety of synthetic char- 
acters as to justify the observation that "it is a form of fish which 
might with little modification become either a selachian, dipnoan, 
or crossopterygian." The long-lived group to which the Port 
Jackson shark {Cestracion) Fig. 6, belongs was exceedingly 
plentiful during the Carboniferous, and the number of species very 




Port Jackson shark, Cestracion philippi (female). Recent; Australia 
(From Dean, after Garman.) 

4 GEOL 



XVi 



50 ANNUAL REPORT OF 

extensive ; but with the close of Palaeozoic time the family became 
decadent. 1 The group of Elasmobranchs as a whole, however, 
began to flourish anew during the Mesozoic, gradually acquiring 
fresh evolutional vigor. It cannot be said to show signs of 
decadence in modern times, since it is represented in apparently 
undiminished numbers in the marine fauna of the present day. 
No members of the group have yet been discovered in the New- 
ark rocks of New Jersey or New England. 

Dipnoans. — The Devonian, which has justly been styled the 
"age of fishes," is remarkable for the introduction of two great 
subdivisions of Pisces, known commonly as Dipnoans and 
Ganoids, both of which are represented sparsely in the modern 
fauna. To* the Dipnoans, or Lung-fishes, belong the "Barra- 
munda" or Neoceratodus of Queensland, and two other genera, 
one of them (Protopterus) inhabiting African, and the other 
(Lepidosiren) South American rivers. As indicated by the com- 
mon name of Lung-fishes, or Dipneusti, these fishes are remark- 
able for having pulmonary respiration, there being a functional 
lung (paired in the two last-named genera) in addition to' the 
regular gills, thus enabling them to live out of water for con- 
siderable periods. The action of the lungs in conjunction with 
the gills furnishes a suggestion as to> the manner in which air- 
breathing vertebrates have probably originated from gill-breath- 
ing, fish-like progenitors. Indeed, owing to the striking resem- 
blances which Dipnoans present to amphibians in their vascular 
system and lungs, many have supposed that the former group 
was directly ancestral to the latter. The best modern opinion, 
however, is inclined to doubt that these resemblances are indica- 
tive of direct ancestral relations, regarding them rather as the 
outcome of physiological convergence, associated with adaptive 
and parallel modifications in structure, and due to the influence 
of a similar environment. It appears more probable that both 
Lung-fishes and amphibians have been derived from some primi- 
tive crossopterygian (ganoid) ancestor, not very divergent from 
the Elasmobranch stem, and subsequently became modified in 
certain respects along parallel lines. 



1 Hay, O. P., The Chronological Distribution of the Elasmobranchs. Trans. 
Amer. Phil. Soc, vol. xx. (igoi), pp. 63-75. 



THE STATE GEOLOGIST. 51 

The habits of existing Lung-fishes are interesting. Neocera- 
todus lives all the year round in the water, there being no evidence 
that it ever becomes dried up in the mud, or passes into* a summer 
sleep in a cocoon; and its paired fins, moreover, are useless for 
progression on the land. The following account of the habits of 
the remaining genera is taken from the "Cambridge Natural His- 
tory" : 

"Protopterus has a wide distribution over the middle portion of the great 
African continent, * * * and is usually found in marshes in the vicinity of 
rivers. The tail is the principal organ of locomotion, and by its means the fish 
is capable of remarkably quick, agile movements. When slowly moving over 
the bottom of an aquarium the paired limbs are observed to move to and fro 
on opposite sides alternately in somewhat bipedal fashion. The limbs are use- 
less for swimming, although it is possible that they may be helpful in creeping 
over the bottom, or in balancing, or as tactile organs. Protopterus is said to 
breathe by its lungs as well as by its gills, and to rise to the surface at short 
intervals to take in fresh air. In the dry seasons the marshes in which Pro- 
topterus lives become dried up, and to meet this adverse change in its sur- 
roundings the fish activates, or passes into a summer sleep, until the next 
rainy season brings about conditions more favorable to active life. Prepara- 
tory to this summer sleep, and before the ground becomes too hard, the fish 
makes its way into the mud to a depth of about 18 inches, and there coils itself 
up in a flask-like enlargement at the bottom of the burrow. * * * While 
encapsuled in its cocoon the fish is surrounded by a soft, slimy mucus, no 
doubt for the purpose of keeping the skin moist, and its lungs are the sole 
breathing organs, the air passing from the open mouth of the burrow through 
the hole in the lid directly to the mouth of the animal. * * * The length 
of the summer sleep naturally varies with the duration of the dry season, and 
probably it lasts on the average nearly half the year (August to December). 
The cocoons, embedded in an outward casing of hardened mud, have often 
been brought to Europe, and when placed in water of suitable temperature the 
long torpid Protopterus escapes from its prison in a perfectly healthy condi- 
tion and resumes its partly branchial and partly pulmonary mode of breath- 
ing. 

"Lepidosiren paradoxa, probably the only species of the genus, is confined to 
South America. * * * Of sluggish habits, the fish wriggles slowly about 
at the bottom of the swamp like an eel, using its hind limbs in an irregular 
bipedal fashion as it wends its way through the dense network of subaqueous 
plants. * * * Like other living Dipneusti, Lepidosiren rises to the surface 
to breathe. The intervals are, however, very variable, and no doubt depend 
on the relative purity or impurity of the water. Both expiration and inspira- 
tion are said to take place through the mouth. The snout is protruded on the 
surface and the creature expires. After being withdrawn for a moment the 
head is again projected and inspiration takes place through the partially 
opened lips. When the fish finally sinks a few bubbles of surplus air escape 
through the gill-clefts. * * * Like its African relative, the fish ceases to 
feed on the approach of the dry season and eventually hibernates at the dilated 
extremity of a tubular burrow, the entrance to which is plugged by a small 



52 



ANNUAL REPORT OF 



lump of clay perforated by several round holes. On the rising of the water at 
the next rainy season the Lepidosiren pushes out the plug and soon emerges 
from its burrow. The breeding season begins soon after the escape of the 
fish." 




Fig. 7. 

Dipterus valenciennesi Sedgw. and Murch. Lower Old Red Sandstone; 
Scotland. Lateral aspect, restored. X 3 A- (From Dean.) 



THE STATE GEOLOGIST. 



53 




54 ANNUAL REPORT OF 

Concerning the origin of Lung-fishes as a group, it is further 
observed in the same work, that "it seems reasonable to look for 
their ancestors in the early Devonian Crossoptergii with acutely 
lobate fins, or, with greater probability, to> some still more primi- 
tive Crossopterygian with simple, non-rhizodont teeth, capable by 
fusion of giving rise tO' massive tritoral plates." Throughout the 
Palaeozoic this group of fishes formed a conspicuous feature of 
the vertebrate fauna, and although they appear to have attained 
their maximum development and specialization during the Devon- 
ian, they did not become entirely insignificant until near the close 
of the Trias. Teeth similar to* those of the recent Neoceratodus 
are profusely distributed throughout Triassic rocks of the world, 
but none have been obtained thus far from the eastern part of the 
United States. It has been shown in a highly instructive manner 
by Dollo that the oldest known Lung-fishes, such as Dipterus 
(Fig. 7) and its associates, are the most archaic, and that 
their modern representatives have been derived from them by a 
series of retrogressive changes; or, in other words, the latter 
have much the same relation to the former as the degenerate stur- 
geons and paddle-fishes to their Palaeozoic ancestors, the Palceon- 
iscidce. Owing to a fortunate abundance of material it is possible 
to select a series of genera, beginning with Dipterus, and termin- 
ating with modern forms, which illustrate the evolution of the 
group both in structure and in chronological sequence. Some 
of the more important structural modifications observable in the 
transition from the older to the recent genera are : ( 1 ) the grad- 
ual union of isolated median fins to form a continuous fin; (2) 
the conversion of a heterocercal tail into a symmetrically formed 
one; (3) the degeneration of the squamation, the thick, ganoid 
scales of the earlier types being replaced by thin, non-ganoid 
scales, or the skin becoming almost entirely naked; (4) a reduc- 
tion in the number of cranial dermal bones and the loss of their 
original ganoid investment; (5) the suppression of the jugular 
plates, and (6) a reduction in the size of the opercular bones. 

Ganoids. — The final and one of the most important contin- 
gent of the Devonian fauna is furnished by Ganoids, or enameled- 
scale fishes. These are divided into two orders, the so-called 
"fringed-fmned" {Crossopterygian) and the "stout-finned" {Ac- 



THE STATE GEOLOGIST. 55 

tinopterygian), from which the manifold variety of modern 
bony fishes has been derived. Both of these orders are repre- 
sented in the Devonian, but the former greatly predominate, and 
the latter only begin to outstrip them during the Carboniferous. 
There is but little reason to doubt that the fringe-finned Ganoids 
gave rise to the class of amphibians, which makes its first appear- 
ance in the Carboniferous, this class in turn being ancestral to 
reptiles, and the latter to birds and mammals. The history of 
Crossopterygians is strikingly similar to that of Dipnoans, in that 
the majority of forms become extinct before the close of the Meso- 
zoic, although in each case a few moribund survivors continue on 
to the present day. Only a solitary member of the order occurs in 
the Xewark series of this State, a large form known as Diplurus, 
of which not more than three or four examples have come to light. 
A more particular notice of this form will be found in a subse- 
quent section of this report. 

Our attention may now be claimed by the important order of 
Acanthopterygii, which embraces not only large numbers of enam- 
eled-scale fishes, but all modern Teleosts, or so-called "bony 
fishes." The earliest and most primitive member of this order 
is Cheirolepis, which occurs in the Devonian of North Britain and 
Canada; but this is succeeded in the Carboniferous and Permian 
by a variety of forms, all exhibiting the same general features, and 
commonly grouped in the single family Palaeoniscidae. There is a 
marked resemblance between the members of this family and 
modern sturgeons and paddle-fishes ; these latter, accordingly, can 
hardly be looked upon other than as late survivors of the ancient 
stem. Their similarity of structure is most evident in the struc- 
ture of their fins, especially the heterocercal tail, and in the pres- 
ence of characteristic plates (the so-called infraclavicles) in the 
jugular region. As for the degeneration of teeth and scales in 
recent forms, these seem to be characters of minor importance. 
Hence we may say that primitive sturgeons arose in the Devon- 
ian, and after giving off more specialized branches during the 
Palaeozoic and Mesozoic, maintained a conservative existence 
down to the present day. Consequently, the longevity of the 
sturgeon tribe is no less remarkable than that of Lung-fishes, 
fringe-finned ganoids, and cartilaginous fishes like the Port Jack- 
son shark. 



56 ANNUAL REPORT OF 

Throughout the Devonian and Carboniferous, stout-finned 
Ganoids appear to have been represented by but this one group of 
primitive sturgeons. During the Permian, however, a typical 
"expression point" was reached, when a new suborder arose 
through various modifications of the skeleton. These latter in- 
volved atrophy of the upper lobe of the heterocercal tail, special- 
ization of the fins, and loss of the infraclavicular plates already 
alluded to. Although represented by but a single genus {Acentro- 
phorus) in the Upper Permian, the new suborder — known as 
Protospondyli — blossomed forth in surprising variety and at- 
tained world-wide distribution during the Trias, giving rise at the 
same time to a still higher suborder (Isospondyli) . This last con- 
tinued on during the Jurassic in the midst of the still dominant 
Protospondyli, until finally in the Cretaceous this and still higher 
suborders became supreme, practically monopolizing the seas, as 
do their descendants at this day. 

To recapitulate briefly the history of the sturgeon tribe, we 
should bear in mind its introduction in the Devonian, its flourish- 
ing condition throughout the later Palaeozoic, its giving rise in the 
Permian to a new suborder known as Protospondyli, and its per- 
sistence with only minor modifications until modern times. As for 
its Permian offshoot, this group acquired great importance during 
the Trias, giving forth still higher suborders, and these in turn 
leading to modern bony fishes. Inasmuch as the fish-bearing rocks 
of New Jersey are of Triassic age, it is not surprising to find the 
fauna largely composed of Protospondyli. The occurrence is to 
be expected here of sturgeon-like fishes, more highly specialized 
than the primitive Palceoniscidce, and less SO' than the four modern 
genera of sturgeons and paddle-fishes; and this expectation is 
realized. 

General Nature of the Boonton Fish Fauna. — Of the half 
dozen genera represented in the Triassic rocks of New Jersey, 
and likewise in New England, the one which is numerically the 
most abundant, and at the same time represented by the largest 
number of species, is that which has received the name of Semi- 
onotus. This form, with its abbreviate heterocercal tail, modified 
fin-structure and absence of infraclavicular plates, together with 
its ossified arches of the vertebral axis, falls within the definition 



THE STATE GEOLOGIST. 57 

of Protospondyli. The next most important genus, Catopterus, 
and the nearly related Dictyopyge, have a less highly modified 
organization, and thus approach more closely to the primitive 
sturgeons, or Palcconiscidcz. Acentrophorus, though not occur- 
ring in the New Jersey Trias, is present in the Connecticut Valley 
region, and belongs with Semionotus amongst the Protospondyli. 
Hence, the afore-named genera, under which the majority of local 
species are comprised, may all be regarded as more or less prim- 
itive sturgeon-like fishes. Of the remaining genera, each of which 
is represented by a single species only, Diplurus is a member of 
the fringe-finned and Ptycholepis of the stout-finned or division 
of Ganoids. The Newark series is totally lacking in remains 
of sharks or lung-fishes, a circumstance which may possibly 
be associated with sedimentary conditions. These latter will be 
considered immediately. 

For the benefit of many who may not be specially familiar with 
the teachings of palaeontology, or who have but slight acquaint- 
ance with fossil fishes in general, it may be well to point out very 
distinctly that the Boonton fishes differ markedly from ordinary 
types of fishes now living. Consequently, the statement which 
one hears frequently asserted with more or less positiveness that 
this or that fossil specimen is exactly like a modern perch, or 
sun-fish, or other familiar form, springs from ignorance and 
careless observation. The nearest comparison with modern types 
that can be made is, as we have already explained, with the stur- 
geon, a comparatively rare form, and notably distinct from our 
common fresh-water fishes. One of the most obvious character- 
istics of the latter, as everyone knows, is that they have bones. 
The very name of "shad" is immediately suggestive of a fish "full 
of bones." That is to say, there is, first of all, a "back-bone," 
or ossified vertebral column, with stout spines above and below; 
secondly, there are well-ossified ribs, these being a conspicuous 
feature, and lastly, in many forms at least, there are numerous 
fine inter-muscular bones. The head also, in modern bony fishes, 
is well ossified. But none of the Boonton fossils exhibit these 
features, save only in some species the ribs and vertebral arches 
(but not the centra or body of the vertebrae) are imperfectly 
ossified. 



58 ANNUAL REPORT OF 

Another very notable difference is that the Boonton fishes do 
not have round or cyloidal, over-lapping scales ; but instead, these 
are rhomboidal, enamel-like and typically united by a peg-and- 
socket articulation. And again, we must take due note of the 
fact that the tails of the Boonton fish are very unlike those of 
modern Teleosts, or "bony fishes," the vertebral column project- 
ing into the upper caudal lobe and making that lobe longer and 
larger than the lower lobe. The unsymmetrical or heterocercal 
caudal fin, and the presence of fine ray-lets or "fulcra" along 
the borders of all the fins are characters by which the fossil species 
may be told at a glance, from the vast majority of recent forms. 

Reconstruction of Physical Conditions. — An investigation into 
the nature of sedimentation over the Triassic area enables us to 
reconstruct more or less perfectly in imagination the former 
environment of the Boonton fish fauna, and to account with some 
plausibility for the sudden extinction and preservation of vast 
numbers of creatures. 

Both in New Jersey and New England the inference may be 
drawn from a variety of evidence, such as geographical surround- 
ings, composition of the sediments, presence of ripple-marks, 
abundance of land plants and similar indications, that the rocks 
of the Newark group were laid down under shallow-water con- 
ditions in proximity to the land. In the Connecticut Valley 
region the strata were clearly deposited in a sort of embayment, 
bounded on either side by eruptives of the mainland, and it is 
even possible to determine the current directions over part of this 
area, as has been done by Professor Emerson, of Amherst. As 
the tide rose and fell, alternately covering and leaving bare exten- 
sive mud-flats, huge reptiles, the like of which no longer exist, 
roamed in large numbers up and down the shore, searching their 
prey and leaving tell-tale footprints, which have been preserved 
from their day to this. 

Little else but footprints bears witness to 1 the existence of these 
weird creatures, a fact which offers a striking commentary on the 
imperfection of the palseontological record. Although for a long 
time regarded as imprints made by birds, it is now known that 
these are traces of reptiles belonging to the order of Dinosaurs, 
whose gait was bipedal. In New Jersey, also, similar tracks have 



THE STATE GEOLOGIST. 59 

been found, though less plentifully, and on some slabs may be 
seen impressions of rain-drops that fell incredibly long ages ago. 
All these facts are of significance for our present purpose, but 
there are others more important. We know that deposition of 
Triassic sediments over both the areas under consideration was 
accompanied by great volcanic activity, and the question at once 
arises whether there may have been any connection between such 
phenomena and the sudden mortality of fishes on a large scale. 
An affirmative answer appears to us not only legitimate, but 
highly plausible. 

If one inquires what are the reasons for believing that the 
mortality was accomplished suddenly and on an extensive scale, 
it may be pointed out that no other explanation can account for 
the remarkable abundance of these fish remains in beds of limited 
thickness ; hence, the destruction must be attributed to some un- 
usual cause or causes. Now, amongst the possible causes which 
are known to have produced similar results in other instances, 
those which proceed from volcanic and seismic disturbances 
acquire force by reason of the established contemporaneity of 
these agencies. The conditions which we are justified in suppos- 
ing to have existed here were not such as involve the partial or 
total evaporation of land-locked waters, or irruptions from the 
outer sea into sheltered, more or less brackish inlets. Nor does 
the copious discharge of fresh water from the mouths of estuaries 
offer a likely explanation for so widespread a destruction of 
ichthyic life. To assume that these creatures perished from an 
outbreak of parasitic diseases would be a wanton hypothesis. 
There remains finally the pleausible conjecture of earthquake 
shocks and volcanic explosions — the two 1 being closely related — 
shocks killing marine life by the violence of the concussion, and 
volcanoes either from the heat of the lava, or from the abundance 
of ashes and poisonous gases. 

It has been repeatedly observed that earthquake shocks have 
been followed by the washing ashore of vast quantities of dead 
fish. The learned Greek geographer, Strabo, 1 for instance, men- 

J The account given by Strabo (Geog. vi., 2, 11) of the destruction of fish 
life by submarine disturbances in the vicinity of the Lipari Islands, near Sicily, 
reads as follows : 



60 ANNUAL REPORT OF 

tions the remarkable effects of earthquakes in ancient times, and 
gives a particular account of the upheaval of an island in the 
iEgean, parallel occurrences being the sudden formation of 
Monte Nuovo, near Naples, in 1538, and of a new island near 
Santorin, in 1707. All these considerations lend the color of 
plausibility to the hypothesis that either seismic or volcanic dis- 
turbances, or both together, stand in causal relation to the Boon- 
ton fish beds. Nevertheless, the means at our disposal do not 
permit us to push the hypothesis further, so as to arrive at a 
demonstration of the real cause or causes. 

Progress of Palmchthyology. — Before closing this general ac- 
count of the Triassic fishes of New Jersey, it may be of interest 
to some to' take a brief retrospect over the history of that branch 
of natural science which is concerned with the investigation of fos- 
sil fishes. In so- far as this class of organisms was one of the 
earliest to attract attention in the fossil state, it may be claimed 
that palceichthyology is coeval with the broader field of palaeon- 
tology in general. The earliest mention of fossil fishes in litera- 



"Posidonius says that at a time so recent as to be almost within his recol- 
lection, about the summer solstice and at break of day, between Hiera [now 
called Volcano] and Euonymus [one of the Lipari, not certainly identified], 
the sea was observed to be suddenly raised aloft and to abide some time raised 
in a compact mass, and then to subside. Some ventured to approach that part 
in their ships ; they observed the fish dead and driven by the current, but being 
distressed by the heat and foul smell were compelled to turn back. One of 
the boats which had approached nearest lost some of her crew, and was 
scarcely able to reach Lipari with the rest, and they had fits like an epileptic 
person, at one time fainting and giddy, and at another returning to their 
senses ; and many days afterwards a mud or clay was observed rising in the 
sea, and in many parts the flames issued, and smoke and smoky blazes." 

A chapter in Pliny's Natural History (ii., 89), which is devoted to islands 
that have been uplifted from beneath the sea, contains an altogether similar 
account : "Opposite to us, and near to Italy, among the ^Uolian isles, an 
island emerged from the sea; and likewise one near Crete, 2,500 paces in 
extent, and with warm springs in it; another made its appearance in the third 
year of the 163d Olympiad (B. C. 125) in the Tuscan gulf, burning with a 
violent explosion. There is a tradition, too, that a great number of fishes were 
floating about the spot, and that those who made use of them for food im- 
mediately expired." 

Other well-known instances of the sudden destruction of fish life in enor- 
mous quantities are those following the destruction of disturbances at Vera 
Cruz in 1742, and at Sumatra in 1755. The recent history of tile-fishes off the 
coast of Massachusetts is also extremely suggestive. 



THE STATE GEOLOGIST. 61 

ture is attributed to Xenophanes of Colophon, who flourished to- 
wards the end of the sixth century of the pagan era, and was 
founder of the Eleatic school of philosophy. Only a few frag- 
ments of his writings have come down to> us, but he is reported 
by later authors to have commented upon the remains of fishes 
and other animals in the fossil state, their occurrence having been 
explained by him in a most sagacious manner. He not only in- 
ferred from them the former transgression of the sea over the 
land, but also the possibility of future submergence, with accom- 
panying extinction of all forms of terrestrial life. 

Xanthus and Herodotus, of the fifth century B. C, enter- 
tained similar opinions concerning the nature of fossils, and it is 
evident from the writings of numerous Greek and Roman au- 
thors, both prior to and after the beginning of the Christian era, 
that petrified remains attracted considerable attention. The Em- 
peror Augustus even possessed a collection of fossil bones. At 
a later period, however, the views of Aristotle, especially those 
relating to spontaneous generation, exerted a baneful influence 
upon the interpretation of nature, it being assumed that living 
creatures could spring into existence and acquire of themselves 
almost any conceivable shape; and if this were possible for living 
creatures, so also might it be possible for mineral matter to as- 
sume endless variety of form. In consequence, fossils were for 
a long time regarded as fortuitous aggregations which had been 
formed within the rocks, or had become moulded on the spot 
through occult agencies, or through the medium of a vis plastic a. 
A rival theory that fossils were the remains of bodies which had 
been overwhelmed by the Scriptural deluge, afterwards becoming 
preserved in the rocks, also engrafted itself firmly upon the popu- 
lar imagination. 

Leonardo da Vinci, one of the most original and versatile gen- 
iuses the world has seen, and Girolamo Fracastoro, his younger 
contemporary and fellow-countryman, were among the first to 
ridicule the prevailing misconceptions of their time (early part of 
the sixteenth century), and to point out the true nature of fossils 
in convincing manner. Those interested in the development of 
geological and palseontological science during the formative per- 
iod of their history will find excellent accounts in Sir Charles 



62 ANNUAL REPORT OF 

Ly ell's "Principles of Geology," in von Zittel's "History of 
Geology and Palaeontology," in Andrew Dickson White's "His- 
tory of the Conflict oi Science with Theology," in Huxley's "Es- 
say on the Progress of Palaeontology," and numerous similar 
works. 

As an example of the persistence with which the minds even 
of learned men lent themselves to absurd and impossible theories, 
instead of heeding the sagacious explanations of Fracastoro and 
others, we may point to one of the early occasions when a scientific 
body was addressed on the subject of fossil fishes. An instance 
is furnished by J. P. Maraldi's communication to the French 
Academy on Veronese fossils, an abstract of which is published 
in the proceedings of that society for the year 1703. 1 Some 
general comments on the appearance of Bolca fishes, and others 
from Sicily and Phoenicia, are followed by suggestions concern- 
ing their origin, which at the present day seem most curious. 2 

Fossil fishes from the Monte Bolca locality, near Verona, also 
furnish the subject for an address before the Royal Irish Acad- 
emy 3 towards the close of the eighteenth century, this being the 
earliest paper in English devoted to this class of remains. The 
discovery of fossil elephant remains in various parts of Europe 
and America gave rise to animated discussions of gigantology; 



1 Hist, de 1' Acad. Roy. des Sciences, annee 1703, pp. 22-24. Paris, 1720. 
Consult also G. Astruc's "Histoire naturelle de la Province de Languedoc," 
chap. x. Paris, 1757. 

2 The passage may be quoted as follows : "Qui peut avoir porte ces poissons 
et ces coquillages dans les terres, et jusques sur le haut des montagnes? II 
est vraisemblable qu' il y a des poissons souterrains comme des eaux souter- 
rains, et ces eaux, * * * s' elevent en vapeurs, emportent peut-etre avec 
elles des oeufs et des semences tres-legeres, apres quoi lorsqu' elles se con- 
densent et se remettent en eau, ces ceufs y peuvent eclorre, et devenir poissons 
ou coquillages. Que si ces courants d' eaux deja eleves beaucoup au-dessus 
du niveau de la mer viennent * * * enfin a. abandonner de quelque maniere 
que ce soit les animaux qui s' y nourissoient, ils demeureront a sec, et envel- 
oppes dans les terres, qui en se petrifiant les petrifieront aussi. Ces eaux 
elles-memes peuvent se petrifier apres avoir passe par de certaines terres, et 
s' etre charge de certains sels. Si toutes les pierres ont ete liquides, comme 
le croyent d' habiles physiciens, cette espece de systeme en est plus recevable." 

3 Graydon, G., On the Fish Enclosed in Stone of Monte Bolca. Trans. R. 
Irish Acad., vol. v. (1794), p. 281. 



THE STATE GEOLOGIST. 63 

these bones being regarded by many as remains of human giants, 
the most famous specimen passing for the actual skeleton of 
Teutobochus rex. But it would prove altogether too lengthy a 
task for the limits of the present article to sketch even rapidly the 
history of this branch of natural science since the time of Linne 
and Artedi, the two great Swedish naturalists with whom the 
scientific study of fishes properly begins. It is to be noted, how- 
ever, that very few contributions can be claimed to- have mater- 
ially advanced the science of palaeichthyology prior to the time 
of Louis Agassiz, whose well known "Poissons Possiles" con- 
stitues even to this day the most valuable repository of informa- 
tion we have on the whole subject. 

In Agassiz's monograph are enumerated more than one thou- 
sand species of fossil fishes, the greater part of which are carefully 
described and excellently illustrated. The publication of this 
work marked an epoch, not only in palaeontology, but general 
zoology as well, since one of its most brilliant results was the 
discovery of certain fundamental laws, a knowledge of which has 
aided wonderfully in strengthening the doctrine of evolution. 
Without doubt the most far-reaching of these in its consequences 
is the analogy which he pointed out between the embryonic phases 
of recent fishes and the geological succession of the class; whence 
followed the generalization, "The history of the individual is but 
the epitomized history of the race." Another notable result was 
the recognition of his so-called prophetic or synthetic types, or 
such as embrace features in their organization which afterwards 
become distributed amongst various groups, never again to be 
recombined. Yet more fruitful was Agassiz's insistence that the 
comparative anatomy of a group, including its palseontological 
record, should be studied in connection with the comparative 
embryology of the same; since, as he maintained, "the results of 
these two methods of inquiry complete and control each other." 

Since the time of Louis Agassiz the scientific investigation of 
fossil fishes has made steady and most satisfactory progress. The 
ichthyic faunas of different horizons and localities are known 
in many cases almost as well as those of modern regions, and 
details of structure have been worked out in the most minute 
and painstaking manner. Our knowledge of the history of this 



64 ANNUAL REPORT OF 

class of vertebrates has been vastly extended, and lines of descent 
have become revealed which afford new and precious insight 
concerning the inter-relations of different groups. If it was pos- 
sible for Agassiz to reconstruct accurately the entire skeleton of a 
fish from a single scale, it is possible for us now to- treat whole 
faunas in much the same way, since we are able to trace their 
origin, migrations and genetic relations — in many cases at least — 
and on bringing all these facts together, to' observe the progress 
of evolution taking place, as it were, before our eyes. 

Contributions to our Knowledge of American Triassic Fishes. 
— We must now turn from this imperfect survey of the scope and 
progress of the science t0> an equally rapid consideration of the 
work that has been done on American Triassic fishes. As early 
as the first decades of the preceding century the pioneers of 
American geology became interested in the fossil fishes and 
reptilian foot-prints of the Connecticut Valley sandstone, several 
communications in regard to them having been furnished by 
Hitchcock, 1 Silliman, 2 Mitchell 3 and Dekay. 4 They were also^ 
brought at an early date to' the attention of scientists abroad, 
Brongniart, Agassiz, Lyell and Egerton having successively com- 
mented upon them during the first half of the century. But it 
is to the Redfields, father and son, who wrote between 1837 



1 Hitchcock, E., Discovery of Fossil Fish. Amer. Journ. Sci., vol. iii. (1821), 
pp. 365-366. Ibid., vol. vi. (1823), p. 43. Final Report on the Geology of 
Massachusetts, vol. ii. (1841), pp. 458-525. 

2 Silliman, B., Miscellaneous Observations, etc. Amer. Journ. Sci., vol. iii. 
(1821), pp. 216, 365. 

3 Mitchell, S. L., Observations on the Geology of North America. 1818. 

4 Dekay, J. E., Fossil Fishes, in "Zoology of New York, or the New York 
Fauna" (Part iv., Fishes, pp. 385-387). Albany, 1842. Also an unpublished 
paper read before the Lyceum of Natural History of New York, noticed by 
J. H. Redfield in the Annals of the Lyceum, vol. iv., 1848. 

The titles of these papers, with a single exception, are given by Dr. O. P. 
Hay in his Bibliography and Catalogue of the Fossil Vertebrata of North 
America, published in Bulletin No. 179 of the United States Geological Sur- 
vey (1902). The exceptional paper is the posthumous report of John H. Red- 
field, published in part by Professor Newberry in his Monograph on the Fossil 
Fishes and Fossil Plants of the Triassic Rocks of New Jersey and the Con- 
necticut Valley (1888). American vertebrate palaeontology properly begins 
with the description in 1787, by President Thomas Jefferson, of mastodon re- 
mains from Virginia, followed a few years later by descriptions of the bones 
of Megalonyx, a gigantic sloth. 



THE STATE GEOLOGIST. 65 

and 1857, that we are indebted for the first really satisfactory 
and detailed account of the Triassic fish-fauna of this country, 
these two having described nearly all the important species. Their 
results are embodied in ten contributions, eight by William C. 
Redfield, the elder, and two by John R., the younger; and they 
also brought together a valuable collection, which unfortunately 
has not been preserved in its entirety. 

Some detached notices in regard to Triassic fishes appear also 
in the writings of Ebenezer Emmons, 1 accompanied by a few 
figures, but it was reserved for Professor John Strong New- 
berry to prepare the most elaborate and, on the whole, most 
satisfactory account of this fauna which we possess. His Mono- 
graph, which includes not only fossil fishes, but also fossil plants 
of the eastern United States, embodies a vast deal of painstaking 
and conscientious labor, carried on during the latter part of an 
active career. Since Newberry's time but little has been added 
to our knowledge of American Triassic fishes. An important 
memoir on the genus Semionotus, by Dr. E. Schellwien, 2 of 
Konigsberg, appeared in 1901, in which some details and illus- 
trations are given of two previously known species. Dr. George 
F. Eaton, 3 of Yale University, has also furnished brief accounts 
of several familiar forms, but pointing out a number of anatom- 
ical characters which had been previously overlooked. A sup- 
posed new species of Semionotus was described by the able 
collector, S. W. Loper, 4 in 1893, under the name of "Ischypterus 
nezvberryi," and another doubtful species, which received the 
name of "Ischypterus beardmorei," was illustrated some years 
later in a popular magazine by Mr. J. H. Smith, 5 formerly of the 
Montclair High School. More recently a detached dermal spine 



1 Emmons, E., Geological Report of the Midland Counties of North Caro- 
lina, 1856. — Report of the North Carolina Geological Survey. Agriculture of 
the Eastern Counties, together with Descriptions of the Fossils of the marl 
beds. Raleigh, 1858. — Manual of Geology, second edition. New York, i860. 

2 Schellwien, E., Ueber Semionotus Ag. Schriften der Phys.-Oekonom. 
Gesellsch. zu Konigsberg i. Pr. (igoi), p. 34, pi. i-iii. 

3 Eaton, G. F., Notes on the Collection of Triassic Fishes at Yale. Amer. 
Journ. Sci., ser. 4, vol. xv. (1903), pp. 259-268, pi. v., vi. 

* Loper, S. W., On a new Fossil Fish. Popular Science News (1893). 
5 Smith, J. H., Fish Four Million Years Old. Metropolitan Magazine, vol. 
xii. (1900), pp. 498-506. 

5 GKOL 



66 ANNUAL REPORT OF STATE GEOLOGIST. 

from the Lower Trias of Idaho, apparently belonging - to Astera- 
cantlius, has been described by H. M. Evans 1 as a new species of 
Cosmacanthus. This last-named species is the only ichthyodoru- 
lite yet recorded from the American Trias, and the total absence 
of Elasmobranch remains in the eastern area may be regarded, 
so far as the evidence goes, as straightening our belief that these 
sediments were deposited under brackish water conditions. 

One other western locality furnishing fossil fishes of sup- 
posed Triassic age is worthy of brief mention in this connection. 
During the years 1879 and 1882 a small collection of ichthyic 
remains was obtained by Dr. C. D. Walcott, Director of the 
United States Geological Survey, in the Kanab Valley, Utah, 
and adjoining regions in Arizona. These remains, which have 
recently been placed in the hands of the writer for investigation, 
are extremely fragmentary, and do not premit of accurate specific 
determinations. Of the few genera which are tolerably well 
indicated, such as Pholidophorus and several Lepidotus-like 
forms, it cannot be said that they evince anything in common 
with the Triassic fauna of the eastern States. Some resemblance 
is to be noted between the Kanab fish-fauna and that of Perledo, 
near Lake Como, but the general aspect of the material collected 
by Walcott is much more suggestive of Jurassic than of Triassic 
relations. This might very well happen notwithstanding the 
horizon be definitely proved by stratigraphic and other evidence 
to be of Triassic age, as other instances of pioneer faunas and 
overlapping types are not uncommon. It does not appear, however, 
that the data thus far obtained warrants more than a plausible 
supposition that the Kanab beds are of Triassic age, their reddish 
color and relative position being consistent with what we should 
expect of rocks of that horizon. Accepting the evidence furnished 
by the fossil fishes at its full value, we shall have to regard the red 
beds of Kanab Canon as belonging presumably to the Lias. 



1 Evans, H. M., A. New Cestraciont Spine from the Lower Triass'c of Idaho 
Bull. Dept. Geol. Univ. of California, vol. iii. (1904), pp. 397-402, pi. xlvii. 



The Triassic Fishes of New Jersey. 



BY C. R. EASTMAN,, HARVARD UNIVERSITY. 



I. Preliminary considerations. 



SUMMARY. 

PAGE. 



i. General constitution of the Triassic fish-fauna of New Jersey, 

2. Physical condition of the remains, and inferences as to probable 

causes of destruction, 68 

3. Relations of the fauna to those of other regions, 70 

4. Evidence in regard to homotaxial relations of the Newark 

series, 71 

5. Reference of the Newark series by leading authorities to the 

Uppermost Trias, 7 1 

6. Table showing correspondence between the Newark fish fauna 

and that of the Alpine Muschelkalk, 72 

II. Systematic descriptions. 

ACTINOPTERYGII. 

1. Family Semionotidce. 

Genus Semionotas, 73 

Genus Accntrophorus, 94 

2. Family Catopteridce. 

Genus Catopterus, 95 

Genus Dictyopyge, 99 

3. Family Eugnathidce. 

Genus Ptycholepis, 100 

CROSSOPTERYGII. 

1. Family Coelacanthidce. 

Genus Diplurus, 101 

PRELIMINARY CONSIDERATIONS. 

The character of the Triassic fish-fauna of the eastern United 
States from Virginia northward is singularly homogeneous and 
monotonous. All told, there are only half a dozen genera repre- 

(67) 



68 ANNUAL REPORT OF 

sented, four of which are known by a solitary species each. Of 
the remaining genera, Catopterus and Semionotus, the latter is 
numerically the more important, and is also represented by a 
larger number of species. 

It is often difficult to distinguish the species of Semionotus 
from one another, except in the case of well preserved individuals, 
but the genera can always be separated with ease. The serration 
oi the posterior scale-borders in Catopterus, and delicately 
fringed condition of the anterior ray of all the fins, are characters 
by which any member of this genus can be recognized at a 
glance. The fringed appearance of the fins just mentioned is 
due to' the presence of numerous spine-like splints or raylets 
known as fulcra, which are peculiar to ganoid fishes — or those 
having rhomboidal, enameled scales. According to the familiar 
dictum of Johannes Muller, "every fish with fulcra on the an- 
terior edges of one or more of its fins is a ganoid." The group 
of fishes embraced in this category was vastly more important 
during remote geological periods than in later times, and at 
the present day it is on the verge of extinction. In fact, not 
more than seven genera of the modern fauna can be classed 
as ganoids, according to the more precise definition of this series, 
the most familiar of these being the sturgeon (Acipenser) , gar- 
pike (Lepidosteus), and bow-fin (Ainia). Recent ganoids, with 
the exception of the sturgeon, have acquired a fresh-water 
habitat, whereas their predecessors were chiefly marine. 

It is probable that the Triassic fishes we are about to con- 
sider belonged to a more or less brackish-water fauna, as there 
is abundant evidence to show that the shallow-water sediments 
of the Connecticut Valley Trias, and of the Newark series in 
New Jersey, were deposited under estuarine, or off-shore condi- 
tions. It need scarcely be remarked that of this exclusively ganoid 
fauna, all the genera are now extinct. One of them, Dipluriis, 
belongs to the Crossopterygian or fringe-finned ganoids, of which 
there are but two living representatives — Polypterus and Cala- 
moichthys. The remaining five belong to the group of Actinop- 
terygian fishes, and one of the number, Catopterus, is interest- 
ing in that it stands close to the ancestral line of the sturgeons, 
which originated as far back as the Devonian. 



THE STATE GEOLOGIST. 69 

As to the probable causes which brought about the destruc- 
tion of the immense quantity of fish-life as is found in the Boon- 
ton and other localities, these can only be postulated in a general 
way, and have already been referred to in the preceding pages. 
It is evident that a vast number of creatures met their death sud- 
denly, sank to the bottom and became embedded in sediment 
before their bodies had suffered serious injury, either from decom- 
position or mechanical disruption. Accidental lengthening or 
compression of the body, due to wave or current action, and such 
other deformation as occurred prior to the fossilization process, 
was no doubt accomplished quickly. It is even possible, in some 
cases, to determine the direction of current or wave action, since, 
if two individuals are found lying at right angles to each other 
on the same slab (as in Plate XIV), and one of them is vertically 
and the other longitudinally compressed, it is evident that such 
distortion must have been produced by a force operating - in 
one and the same direction. Friction of the water on the bot- 
tom, and the wash of sediment by tidal action, offer convenient 
and plausible explanations of these appearances. The extent to 
which the original contour of fish skeletons has become distorted 
by accidents of fossilization, which seem to have been unusually 
prevalent at Boonton, cannot be fully appreciated except by those 
who have had considerable experience in collecting, or in the de- 
termination of species. 

A variety of accidental phenomena has been suggested to 
account for the destruction of multitudes of brackish-water or 
marine organisms simultaneously in such manner as to produce 
what are known as "bone-beds" or "fish-beds." Amongst the 
more important of these may be mentioned : ( 1 ) Earthquake 
shocks; (2) volcanic explosions, with the emission of poisonous 
vapors; (3) sudden changes in temperature, or in salinity 
brought about by the shifting of currents, by irruptions from 
the outer sea into sheltered or brackish-water inlets, or by unusu- 
ally copious discharges of fresh water into the open sea; (4) 
the accidental impounding of marine forms within land-locked 
embayments, including coral island lagoons, coal marshes, inun- 
dated areas, etc.; and (5) parasitic infections and other physio- 
logical disturbances. The possibility of some of these agencies 



7 o ANNUAL REPORT OF 

having led to the mortality of Eocene fishes found at Monte 
Bolcac in the Veronese was discussed by prominent Italian geol- 
ogists more than a century ago. 1 

As to the correspondence between the Triassic fauna of eastern 
North America with organic assemblages of other regions, it 
must be admitted that the fishes alone furnish insufficient data 
for correlation. The vertebrate contingent of the Newark fauna 
is essentially a local one, and does not stand in close agreement 
with the corresponding element of the European or South African 
Mesozoic. On the other hand, we must not overlook the fact that 
a certain and not inconspicuous analogy exists between the New- 
ark fish- fauna and that of the Alpine Trias, especially the Vir- 
glorian (Muschelkalk) of Perledo, near Lake Como, which con- 
tains a number of species of Semionotus closely resembling the 
American forms. In the Keuper of Besano both Semionotus and 
Ptycholepis occur, along with other forms having a Liassic aspect, 
and the association of these two genera in our local fauna immedi- 
ately suggests that the Newark beds belong to the uppermost divi- 
sion of the Trias. 

This conclusion with respect to the relations of the Newark sys- 
tem agrees with that shared by most palseobotanists who have 
investigated its flora, and whose opinions are brought together 
by I. C. Russell in his correlation paper on the Newark system. 2 
The testimony furnished by palseobotany on this subject is held 
by most writers to be definite and reliable. According to L. F. 
Ward, 3 the most recent authority to discuss the relations of the 
Newark flora, the evidence of fossil plants fixes the horizon of the 
Newark "with almost absolute certainty at the summit of the 
Triassic system, and narrows the discussion down chiefly to the 
verbal question whether it shall be called Rhaetic or Keuper. 



1 Gazola, G., Lettere recentemente pubblicate suipesci fossili veronesi, con 
annotazioni inediti agli estratti delle medesime. Milan, 1793, and Verona, 1794. 

2 Russell, I. C, Correlation Papers: The Newark System (Bull. U. S. 
Geol. Surv. No. 85, pp. 126-131), 1892. Kummel, H. B., The Newark System 
of New Jersey (Ann. Rept. State Geol. N. J. for 1897, pp. 23-159), 1898. 

3 Ward, L. F., The Plant-bearing Deposits of the American Trias (Bull. 
Geol. Soc. America, vol. iii, pp. 23-31), 1891. Principles and Methods of 
Geologic Correlation by means of Fossil Plants (Amer. Geol., vol. ix, pp. 
34-47), 1 89 1. 



THE STATE GEOLOGIST. 71 

* * * The beds that seem to be most nearly identical, so far 
as the plants are concerned, are those of Lunz, in Austria, and of 
JSFeue Welt, in Switzerland. These have been placed by the best 
European geologists in the Upper Keuper. Our American Trias 
[Newark] can scarcely be lower than this, and it probably can 
not be higher than the Rhsetic beds of Bavaria." 

Newberry was mistaken in supposing that the fishes of the 
Newark system were not nearly related to those of any European 
formation, 1 but agreed with the majority of writers in the view 
that the evidence of fossil plants favored a correlation with the 
Uppermost Trias. Agassiz 2 at one time expressed an opinion 
that the fossil fishes of the Virginia area, and "from the so-called 
New Red Sandsorie, indicate an age intermediate between the 
European New Red and the Oolite." Later he developed this 
view so far as to state that the fossils referred to correspond 
neither with the Triassic fishes of Southern Germany, nor with 
those from the English Lias, and he accordingly referred the New- 
ark rocks to a group intermediate between the Trias and Lias, 
for which there is no European equivalent. 3 

Those desirous of tracing the correspondence between the New- 
ark fish-fauna and various assemblages of the Alpine Trias may 
profitably consult the comparative lists given by Baron de Zigno 
of the species obtained from five well-known localities. In the 
following table we have arranged his list of the forms occurring 
at Perledo and that showing the principal American species in 
parallel columns. For a list of the localities from which fossil 
fishes have been obtained in greater or less abundance in the New- 
ark system one may consult page 57 of the correlation paper of 
I. C. Russell, already referred to. A discussion will also be found ■ 
in the same paper of the probable physical conditions under which 
the beds of the Newark system were deposited : 



1 Newberry, J. S., The fauna and flora of the Trias of New Jersey and the 
Connecticut Valley (Trans. N. Y. Acad. Sci., vol. vi, pp. 124-128), 1887. 

2 Agassiz, L., Proc. Amer. Assoc. Adv. Sci., vol. iv (1850), p. 276. 

3 Idem, Proc. Amer. Acad., vol. iii (1852-57), p. 69. 



72 



ANNUAL REPORT OF 



List of Fossil Fishes occurring in the 
Alpine Muschelkalk at Perlcdo. 

1. Lepidotus serratus Bell. 

2. pectoralis Bell. 

3. Allolepidotus rueppelli (Bell.). 

4. nothosomoides 
Deecke. 

5. Semionotus brevis Bell. 

6. balsami Bell. 

7. inermis Bell. 

8. dubius Bell. 

9. altolepis Deecke. 

10. bellotti Riippel. 

11. irof^ Bell. 

12. hermesii Bell. (MS.). 

13. lepisurus Bell. (MS.). 

14. Archceosemionotus connectens 

Deecke. 

15. Pholidophorus rueppelii Bell. 

16. oblongiis Bell. 

17. lepturus Bell. 

18. " porroi Bell. 

19. curioni Bell. 

20. Urolepis macroptera Bell. 

21. " microlepidotus Bell. 

22. " elongata Bell. 

23. Heptanema paradoxum Riippel. 

24. Belenorhynchus macrocephalus 

Deecke. 



£ij£ 0/ Fossil Fishes occurring in the 
Newark Series. 

1. Semionotus ovatus (W. C. Red- 

field). 

2. robustus (Newb.). 

3. agassizii (W. C. Red- 

field). 

4. gigas (Newb.). 

5. fultus (Ag.). 

6. tenuiceps (Ag.). 

7. micropterus (Newb.). 

8. lineatus (Newb.). 

9. elegans (Newb.). 
10. braimi (Newb.). 

ii. Acentrophorus chicopensis Newb. 

12. Catopterus gracilis J. H. Redfield. 

13. rediieldi Egerton. 

14. Dictyopyge macrura (W. C. Red- 

field). 

15. Ptycholepis marshi Newb. 

16. Diplurns longicaudatus Newb. 



Systematic Descriptions, 

Order ACTINOPTERYQ1I. 1 

Family SEMIONOTID^. 

Trunk more or less deeply fusiform, rarely cycloidal. Cranial 
and facial bones more or less robust, and opercular apparatus 
complete. Gape of mouth small, teeth styliform or tritoral. 
Notochord persistent, vertebras not more than rings. Fin-rays 
robust, fulcra large, dorsal fin not extending more than one-half 
the length of the trunk. Scales rhombic, except occasionally in 
the caudal region. 



1 For sake of convenience, the two most important genera, Semionotus 
and Catopterus, are here treated slightly out of their usual order, the remain- 
ing genera, which are of excessively rare occurrence, being placed after them. 



THE STATE GEOLOGIST. 



73 



Genus S^mionotus Agassiz. 

Trunk fusiform. Marginal teeth slender, conical, somewhat 
spaced, inner teeth stouter; opercular apparatus well-developed, 
with a narrow arched preoperculum. Ribs ossified. Fulcra un- 
usually large. Paired fins small, dorsal fin large, arising at or 
behind the middle of the back, and in part opposed to the 
relatively small anal; caudal fin slightly forked. Scales smooth 
or feebly ornamented, and the narrow overlapped margin pro- 
duced at the angles and at the superior border. Flank-scales 
not more than twice as deep as broad, the dorsal ridge-series of 
acuminate scales forming a prominent crest. — (Woodward.) 

The cranial osteology of this genus is imperfectly known, a 
consequence of the inferior preservation of most of the remains. 
Agassiz, in his great work on Fossil Fishes, described briefly 
the arrangement of cranial plates in 5*. nilssoni, and more recently 
E. Schellwien has furnished us with similar information regard- 



pm<--- 




<B> 



Fig. o. 

Semionotus capensis Woodw. Lateral aspect of head, X Yi. br, branchi- 
ostegal rays; cl, clavicle; co, circumorbitals ; cor, coracoid (?); fr, frontal; 
*. op, interoperculum ; md, mandible ; mx, maxilla ; pa, parietal ; p. cl, post- 
clavicular scale ; p. 0, postorbital ; p. op, preoperculum ; p. t, post-temporal ; 
s. cl, supraclavicle; so, suborbitals; s. op, suboperculum; sq, squamosal; s. t, 
supratemporal. Sensory canals are indicated by dotted lines ; doubtful sutures 
by dashes (after Schellwien). 



ing S. capensis f Fig. 9), both of these forms being trans- Atlantic 
species. Newberry remarks in his Monograph on Triassic Fishes 
that he has "not been able to verify by personal examination 



74 ANNUAL REPORT OF 

the descriptions of the head plates of Semionotus ' given by- 
European authors," but offered on his own part no new infor- 
mation as regards the head structure of American forms. Only 
within the past year has a really satisfactory figure of the head 
of an American species been published, and this, which we owe 
to Dr. G. F. Eaton, is unaccompanied by a textual description. 
In the following paragraphs it is not intended to' present more 
than a general sketch of the cranial structure so< far as it has 
yet been deciphered. 

The membrane bones of the cranial roof form a continuous 
shield, extending from the snout nearly to* the occipital border. 
The two principal pairs of bones are the narrow and elongate 
frontals, reaching from the premaxillaries to ; behind the orbits, 
and the much shorter parietals in contact with them posteriorly. 
As is frequently the case amongst the Semionotidse, these pairs 
are not quite bilaterally symmetrical, but the sutures are more 
regular than in some other genera. Skirting the lateral border 
of the frontals, and extending also over the forward part of 
the parietals, are deep mucous canals, which are developed on 
the under side of the bones, and hence not commonly apparent 
from the external aspect. In 5\ nilssoni (Fig. 10), the impres- 




Fig. io. 

Semionotus nilssoni Ag. Dorsal aspect of head, slightly modified, after 
Agassi, X Vi- a, frontals ; b, parietals ; c, squamosal ; d, postorbital. 

sions of these canals are unusually broad and deep, and so diffi- 
cult to distinguish from sutures that Agassiz was misled into- 
confusing them with the latter. For the benefit of those who 
may care to consult Agassiz's description of the latter head in 
this form, and seek acquaintance with a single perfectly preserved 
individual before attempting the decipherment of imperfect ones, 
we quote from Agassiz's original description as follows : 



THE STATE GEOLOGIST. 75 

"Les fronteaux, a, a, sont fort allonges ; leur prolongement anterieur ne se 
retreat pas tres-considerablement ; en sorte que la tete est moins effilee dans 
cette espece que dans les autres. La suture qui les unit, est inegale, le frontal 
gauche etant plus large que le droit, et faisant saillie sur lui a sa partie 
posterieure. Les parietaux, b, b, sont petits ; le droit est cependant un peu 
plus grand que le gauche. Le mastoiden gauche, en partie conserve, c, montre 
a sa surface de tres-petits tubercules pointus. L'orbite est assez petite; 
les sous-orbitaires qui l'entourent sont etroits et granuleux a leur surface. 
Les plaques buccales, d, considerablement plus larges, semblent completement 
lisses, a en juger du moins par un fragment dont la surface est visible. 
L'opercule est beaucoup plus haut que large; les autres pieces operculaires 
sont enlevees." (Poiss. Foss. I, p. 230.) 

Behind the parietals occur a pair of wedge-shaped plates corresponding 
to the supratemporals of Palaeoniscus. These are followed in turn by the 
scaly post-temporals, which in most species have a decidedly Palseoniscus- 
like aspect. It is remarked by Schellwien, with regard to the plates forming 
the cranial roof, that "die Mittellinie, in welcher die paarigen Platten des 
Schadeldaches an einander stossen, ist keine gerade, sondern mehr oder 
weniger gewellte, anscheinend besonders stark in der Parietalregion. Die 
correspondierenden Platten sind auf beiden Seiten des Kopfes theilweise 
sowohl in der Grosse, wie in der Form verschieden ausgebildet." 



Fig. 11. 

Semionotus nilssonni Ag. Lateral aspect of cranium, X Yi. Lettering as in 
Fig. 10. 

The squamosal is a plate of variable width and irregular shape 
abutting against the parietals and frontals. It is terminated 
anteriorly by a ring of circumorbitals, but its posterior limits 
are apparently not the same for all species. The circumorbitals, 
as their name implies, are a series of small plates surrounding 
the orbit. They are of polygonal contour (Fig. 11), and are 
arranged much in the same manner as in Lepidotus, those along 
the lower border being of larger size and extending some dis- 



76 ANNUAL REPORT OF 

tance in advance of the upper tier. Indications of a mucous 
canal are observable over part of the circumorbital ring in some 
species. Immediately beneath the latter is situated a series of 
suborbitals, which are much larger and less numerous than those 
of Lepidotus, Dapedius and related genera. Evidence of 
specialization is observable here, these large plates having no 
doubt resulted from the fusion of smaller ones. The boundaries 
between the suborbitals and contiguous plates have not been 
satisfactorily determined even in the best preserved individuals. 
The postorbital, or "plaque buccale" of Agassiz, is a large thin 
plate on either side of the head, situated between the circumor- 
bitals and the operculum. It is sometimes in contact with the 
latter plate posteriorly, as in S. bergeri and possibly also' in 
S. nilssoni (although it may have been displaced in the type so 
as to come to occupy this position accidentally), or in other 
cases it may be entirely separated from it by the preoperculum, 
as in S. capensis. 

The opercular apparatus consists of ( I ) a large operculum, of 
variable shape, but generally with a narrower upper border; (2) 
a narrow, falciform preoperculum, with the mucous canal inter- 
rupted and appearing as a series of perforations; (3) a sub- 
operculum, the exposed surface of which generally exhibits a 
sublunate outline; and (4) a triangular interoperculum. The 
posterior borders of the operculum and interoperculum are em- 
braced by a large and heavy plate, often very conspicuous, the 
clavicle. This is similar to' the preoperculum in form, but is much 
more solid, and its terminal angle in front is frequently thickened 
or otherwise prominent. It is succeeded behind by one or two 
enlarged postclavicular scales. There is a series o>f branchiostegal 
rays, but these, like the coracoid, are seldom well preserved, 
and hence not satisfactorily known. The dental characters have 
been indicated with sufficient fulness in the preceding family and 
generic diagnoses. 

In the following systematic discussions, conscientious regard 
has been paid to- the opinions of Professor Newberry, and none 
of the changes here introduced can be said to be inharmonious 
with his views, implied or expressed. But it is clear to everyone 
that this author, with all his clarity of perception, did not always 



THE STATE GEOLOGIST. 77 

carry out his arguments to their logical conclusions, and, whether 
owing to conservatism or other reasons, he often declined taking 
a novel procedure, preferring to abide instead by precedent and 
established usage. In the second place, he was sometimes led 
through caution and hesitancy to doubt his own determinations, 
instances being not at all uncommon where he has contradicted 
himself in this respect. 

As has been remarked by Dr. Eaton, "the late Professor New- 
berry belonged to a school of palaeontologists whose practice it 
was to decide all doubtful cases in favor of a new species." 
Examples of this tendency are to be found in his recognizing a 
distinction between S. fultus and S. macropterus, species which 
had been previously united by J. H. Redfield. Semionotus lahis 
was also regarded as a distinct species, although pronounced a 
synonym of S. tenuiceps by earlier writers, nor are these the 
only instances that might be cited. Even the identity of Eger- 
ton's genus "Ischypterus" with Semionotus was more than sus- 
pected by him, although he appears not to have arrived at a 
decided conviction on this point. Wherever the former generic 
term occurs in the present article, it is to be understood as a 
synonymy of Semionotus, this being the accepted usage. The 
new species of Semionotus described by Professor Newberry 
were named by him as follows : 



Semionotus 

a 


("Ischypterus 
11 


') gigas. 
robustus. 


it 


it 


micro pterus. 


It 


it 


( lineatus. 
X alatus. 


ti 


a 


m 

a 


a 


r lenticularis. 


a 


a 


< modestus. 


ti 


a 


1 elegans. 


(C 


a 


minutus. 



Newberry took occasion to observe more than once in his 
Monograph that his work was liable to modification through the 
discovery of more and better material, and he predicted that 
further investigation would probably reduce instead of increase 
the number of species. The names bracketed together in the 



7& ANNUAL REPORT OF 

above list are treated as synonyms, the legitimacy of which 
course was practically acknowledged by Newberry. For in- 
stance, in the description of his so-called /. alatus, he tells us 
that he "hesitated long before separating it from /. limaius, as it 
is probable that the two will be found to run into each other, so 
that they must be regarded as varieties of one species." Similarly 
the differences between his Ischypterus elegans and /. lenticularis 
were admitted to be so slight as to- be perhaps attributable to 
age or sex; and under his description of /. modestus we read: 
"The fishes most nearly allied to these are those which I have 
included under the name of /. elegans, and it is perhaps not cer- 
tain that they should be regarded as distinct." It will be seen, 
therefore, that no violence is done to> the views of the original 
author, to whom we owe much and valuable enlightenment, in 
introducing a few slight modifications. 

Semionotus ovatus (W. C. Redfield). 
(Plates 4-6.) 



1842 
1847 

1850. 
1888 

18 
1903 



Palceoniscus ovatus, W. C. Redfield, Amer. Journ. Sci., vol. xli, p. 26. 
(?) Tetragonolepis, Sir P. G. Egerton, Quart. Journ. Geol. Soc, vol. 

iii, p. 277. 
Ischypterus ovatus, Sir P. G. Egerton, op. cit., vol. vi, p. 10. 
Palceoniscus ovatus, J. H. Redfield, Monogr. U. S. Geol. Surv., vol. 

xiv, p. 27. 
Ischypterus ovatus, Ibid, loc. cit. 
Semionotus ovatus, G. F. Eaton, Amer. Journ. Sci., [4] vol. xv, p. 266. 



A large species, attaining a total length of about 23 cm. (9 in.), 
with trunk very much deepened midway between the head and 
dorsal fin. Scales large and thick, becoming gradually deepened 
toward the middle of the flanks ; tail strong and considerably ex- 
panded. Number of dorsal and anal fin-fulcra greater than in 
any other species, each fin having sometimes as many as twenty 
or more. Length of the longest fulcrum of dorsal fin nearly 
equaling one-half that of the anterior margin of the fin. 

In the original description of S. ovatus, by W. C. Redfield, it 
is stated that "it exceeds all the known American species in the 
comparative width or roundness of its form, and is also remark- 
able for the large size of its scales. It is of rare occurrence, and 



THE STATE GEOLOGIST. 79 

owing probably to its great thickness, is seldom obtained in a per- 
fect form." The younger Redfield, commenting on the same 
species in 1854, pronounced it "the broadest and most ovate 
species of Palaeoniscus that is known," and added further that "in 
size of the scales it resembles P. Agassizii, but its form will readily 
distinguish it." 

This species is recorded by both of the Redfields from the Con- 
necticut Valley Trias and from Boonton, New Jersey. The same 
distribution is claimed for it by Newberry, who also identifies 
with this species a fragmentary individual from the Triassic Coal- 
field of Virginia, originally referred to- Tetragonolepis by Sir 
Philip Grey Egerton. It is to be observed that all of the more 
perfect examples have been obtained from Boonton, and the rec- 
ognition of this species from other localities depends upon the 
evidence of more or less fragmentary remains. The original of 
Newberry's published figure is now preserved in the American 
Museum of Natural History, in New York. In Plate VI. is repre- 
sented what is evidently a young individual of this species, and 
it will be noticed that some resemblance exists between it and the 
published figure of the so-called S. beardmorei. 

Semionotus robitstus (Newberry). 

1888. Ischyptertis robustus, J. S. Newberry, Monogr. U. S. Geol. Surv, vol. 
xiv, p. 36, pi. vi., fig. 1. 

A species of slightly smaller size than the preceding, and stated 
to be distinguished from it by "the great height, breadth and 
strength of the dorsal fin and its anterior position." Dorsal fin- 
fulcra very numerous, strong, curved; rays of dorsal fin 11, very 
strong. Pectorals relatively long and broad; pelvic fins inserted 
nearly opposite the anterior margin of the dorsal. Dorsal ridge- 
scales well developed, forming a prominent crest; trunk scales 
large and strong. 

This species, of which only two or three examples are known, 
is doubtfully distinct from S. ovatus. During the time this report 
was in preparation Newberry's originals were packed in cases 
awaiting rearrangement in the American Museum of Natural His- 
tory in New York, and hence not available for study. They were 
derived from Boonton, and no others have since been obtained. 



8o ANNUAL REPORT OF 

Semionotus agassizii (W. C. Redfield). 

(Plate L; Plate II., Figs. 5, 9, 10, 12; Plate III., Figs. 1, 2; Plates VII., VIII.) 

1841. Palceoniscus agassizii, W. C. Redfield, Amer. Journ. Sci., vol. xli., p. 26. 
1850. Ischypterus agassizii, Sir P. G. Egerton, Quart. Journ. Geol. Soc, vol. 

vi., p. 10. 
1856. Ischypterus marshi, W. C. Redfield, Proc. Amer. Assoc. Adv. Sci., pt. 

ii., p. 188 (name only). 
1888. Ischypterus agassizii, J. S. Newberry, Monogr. U. S. Geol. Surv., vol. 

xiv., p. 30, pi. iii., Fig. I. 
1888. Ischypterus marshi, J. S. Newberry, ibid., p. 28, pi. ii., Fig. 1. 
1903. Semionotus marshi, G. F. Eaton, Amer. Journ. Sci. [4], vol. xv., p. 264, 

pi. v., Figs. 5, 9, 10, 12; pi. vi., Figs. 1, 2. 

D. 9-10; C. 17; A. 9; P. 12. 

A large and elegantly fusiform species, attaining a total length 
to- the base of the caudal fin of about 25 cm., in which the length 
of the head and opercular apparatus is contained three and one- 
half times. The maximum depth occurs between the paired fins, 
where the number of longitudinal scale-rows is about 20. Num- 
ber of transverse scale-rows, counting along the lateral line, about 
34. Scales universally large and thick. The boat-shaped dorsal 
ridge-scale covering the base of the dorsal fin anteriorly is rather 
small, rounded in front and not notched behind, the posterior 
extremity prolonged instead into a fine point. Fins strong, but 
relatively short, the caudal rather prominently forked, and with 
about 17 rays. Dorsal, anal and pectoral fins with about 14 fulcra 
each, the ventral with about 12. Apparently four dorsal fin-fulcra 
originate on the dorsal line over the basal supports, the fifth being 
slightly less than one-half the length of the anterior fin-margin. 

The original description of this species by W. C. Redfield is 
very meagre, the principal characters noted by him being the 
stoutness of the fins, and the usually disturbed condition of the 
dorsal ridge-scales. A more accurate definition was drawn up by 
John H. Redfield in the report presented by him to the Amer- 
ican Association of Geologists and Naturalists in 1845, portions 
of which were published in the Proceedings of the Association for 
1856, and still others by Professor Newberry, in 1888. Those to 
whom these sources are not readily accessible may find satisfaction 



THE STATE GEOLOGIST. 81 

in having the original description placed before them, which we 
quote as follows : 

"Head narrow and pointed, scales large and smooth, sometimes with faint 
concentric striae; those of the anterior portion of the dorsal ridge very much 
elongated, strong and pointed, and apparently erectile; when in an erect posi- 
tion much resembling rays, and giving the appearance of a comb-like dorsal 
fin; back arched, but not so abruptly as in P. tenuiceps. The widest portion 
of the fish is found just anterior to the ventral fin; pectoral fin moderate; 
anterior raylets rather short; primary rays, six or eight; ventral fins small; 
anterior raylets, about ten; primary rays, about five or six; dorsal fin large, 
triangular, preceded by erect, pointed scales ; anterior raylets very long, twelve 
or more in number; primary, eight to ten; anal fin large, but not so much 
elongated as in P. tenuiceps or P. fultus; anterior raylets very strong, about 
twelve in number; primary rays, six to eight; tail forked, lobes acute, anterior 
raylets rather stout, rays of lower lobe much stouter than those of upper; 
length, seven to eight inches ; breadth, three to three and one-half inches. 
Occurs at Sunderland, Mass. ; Westfield and Middlefield, Conn. ; Pompton and 
Boonton, N. J." 

The additional characters are mentioned by Newberry that the 
dorsal ridge-scales, which are usually depressed, are less strongly 
developed than in S. tenuiceps, and "the arch of the back does not 
show the hump which is so characteristic of that species ; the fins 
are very strong; the fulcra of the dorsal and anal fins unusually 
broad and long, forming arches nearly half an inch wide at the 
base, curving gracefully backward to a point." 

It is further stated by Newberry that fishes answering to the 
above description occur nowhere except at Boonton. As for the 
remarkably similar specimens from the Connecticut Valley, these 
were held by him to constitute a distinct species, which he de- 
scribed under the name of Ischpterus marshi. The latter form 
was supposed to differ from S. agassizii in having a less-deepened 
trunk, weaker dorsal and anal fins, and thicker scales arranged in 
more oblique rows along the flanks. At a subsequent period, 
although there is no published record of it in his writings, he 
appears to have become convinced that actual differences did not 
exist, and that S. marshi should be treated as a synonym of S. 
agassizii. This view certainly accords with all the facts, and is 
adopted in the present paper. But as Newberry did not himself 
propose the abandonment of his S. marshi, it is proper to explain 
this matter more fully. 

6 GEOiv 



82 ANNUAL REPORT OF 

There are preserved in the American Museum of Natural His- 
tory in New York three very excellent specimens of Semionotus, 
from Sunderland, Mass., which were presented to that institution 
a number of years ago by Mr. Robert L. Stuart, and are referred 
to by Newberry in his Monograph under the caption of Ischyp- 
terus marshi. One of them he mentions as "an exceptionally per- 
fect specimen about twelve inches long," this being probably the 
identical individual which is shown in Plate VII. of this report, 
and forms the basis of our restoration in Plate I. Another of the 
trio is represented in Plate VIII., this one having the pectoral fin 
and dorsal ridge-scales very well preserved. After the completion 
of his Monograph, these specimens were again examined by Pro- 
fessor Newberry, and according to the veteran curator, Professor 
Whitfield, were redetermined by him as belonging to S. agassizii r 
this name being thereupon inscribed upon the labels. These speci- 
mens, which may be regarded upon Newberry's authority as be- 
longing undoubtedly to 5. agassizii, have more recently been in- 
vestigated by Dr. G. F. Eaton, of Yale University, and his opinion 
is that no differences are to be observed between them and the 
type of >S\ marshi, which is preserved in the Yale Museum. Dr. 
Eaton's view that the species is "probably common to Massachu- 
setts, Connecticut and New Jersey" is in accord with the original 
statement of Redfield. 

The illustration given in Plate III., fig. I, for the use of which 
we are indebted to Dr. Eaton, shows the head of the type-speci- 
men of the so-called S. marshi, which is poorly represented in 
Newberry's figure. The tail, too, in the same illustration, has been 
largely restored without the fact being so indicated. Certain de- 
tached scales from different parts of the body are likewise repro- 
duced from Dr. Eaton's article in the American Journal of 
Science. Plate I. of the present report having been drawn from 
an actual photograph, it has been thought advisable to leave the 
squamation, including the dorsal ridge-scales, and also the fin- 
rays, exactly as they occur in the original specimen, without at- 
tempting a restoration. 



THE STATE GEOLOGIST. 83 

Semionotus gigas (Newberry). 

Ischypterus gigas, J. S. Newberry, Trans. N. Y. Acad. Sci., vol. vi., p. 
127 (name only). 
1888. Ischypterus gigas, J. S. Newberry, Monogr. U. S. Geol. Sun-., vol. xiv., 
p. 49, pi. xiv., Fig. 3. 

This species is founded upon the fragmentary caudal portion of 
a large example of Semionotus from the Newark series at 
Boonton, the total length of the fish being estimated by Newberry 
to have been about two feet. It is quite possible that the type 
specimen was simply a large-sized individual of S. agassizii, but in 
the absence of all other material the name may be allowed to' stand 
in a provisional sense as indicating a form not clearly distinguish- 
able from the preceding. 

Semionotus fultus (Agassiz). 

(Plate II., Figs. 1-4; Plate IX.) 

1833-36. Palceoniscus fultus, L,. Agassiz, Poiss. Foss., vol. ii., pt. i., pp. 4, 43, 

pi. viii., Figs. 4, 5. 
1841. Palceoniscus fultus, W. C. Redfield, Amer. Journ. Sci., vol. xli., p. 25. 
1841. Palceoniscus macropterus, W. C. Redfield, ibid., p. 25. 
1847. Ischypterus fultus, Sir P. Egerton, Quart. Journ. Geol. Soc, vol. iii., 

p. 277. 
1850. Ischypterus fultus, Sir P. Egerton, ibid., vol. vi., pp. 8, 10. 
1877. Ischypterus fultus, R. H. Traquair, ibid., vol. xxxiii., p. 559. 
1888. Ischypterus fultus, J. S. Newberry, Monogr. U. S. Geol. Surv., vol. xiv., 

p. 34, pi. vi., Fig. 2; pi. vii., Fig. 1. 
1888. Ischypterus macropterus, J. S. Newberry, ibid., p. 41, pi. xii., Fig. I. 
1901. Semionotus tenuiceps, W. H. Hobbs, 21st Ann. Rept. U. S. Geol. Surv., 

pt. iii., p. 56, pi. iii., Fig. A (err ore)} 
1901. Semionotus fultus, E. Schellwien, Phys.-okon. Gesellsch. Konigsberg, 

p. 29, pi. iii., Figs. 4 (?), 5. 
1903. Semionotus fultus, G. F. Eaton, Amer. Journ. Sci. [4], vol. xv., p. 261, 

pi. v., Figs. 1-4. 
1895. Semionotus fultus, A. S. Woodward, Cat. Foss. Fishes Brit Mus., pt.. 

iii., p. 58. 

The synonymy given above is that generally concurred in by- 
recent writers. The two species, S. fultus and S. macropterus,,, 



1 The present writer is not responsible for this determination. The original 
of Fig. B was referred by him to S. fultus, that of Fig. A to Catopterus. 



84 ANNUAL REPORT OF 

were first united by J. H. Redfield in his report presented to the 
American Association of Geologists and Naturalists in 1845, but 
were again separated by Professor Newberry on the ground of 
their seeming to present slight differences in the proportions of 
length and depth — appearances due to varying conditions of 
preservaton. The principal characters distinctive of this species 
may be enumerated as follows : 

D. 10; C. 15; A. 10; P. 10. 

A gracefully fusiform species attaining a total length to the 
base of the caudal fin of about 15 cm., in which the length of 
the head and opercular apparatus is contained three and one- 
half times. The maximum depth of trunk, which is equal to 
about one-fourth the total length, occurs midway between the 
head and dorsal fin, where there are about 20 longitudinal rows 
of scales. Lateral line scales about 33. Dorsal fin arising at 
mid-length, pelvic nearer to anal than to the pectoral pair, arising 
opposite a point directly in advance of the dorsal. Caudal not 
much forked. Anal with 10 rays, partly opposed to hinder half 
of the dorsal, its origin being on the third oblique scale-row in 
advance of the dorsal fin. Dorsal fin-fulcra about 12, anal 10, 
ventral and pectoral 10 each. Apparently four dorsal fin- fulcra 
originate on the dorsal margin over the interneurals. The fifth 
dorsal fulcrum has its origin adjacent to that of the first ray 
(Fig. 12), and is about equal in length to one-half the anterior 
margin of the fin. Scales smooth and not serrated posteriorly, 
the deepest ones occurring in the fourth row behind the clavicular 
arch; these are about twice as deep as they are wide in their 
exposed portion. Dorsal ridge-scales acuminate. 



THE STATE GEOLOGIST. 85 




Fig. 12. 
Semionotus fultus Ag. Fulcra and anterior rays of dorsal fin 

As already remarked, the sole criterion relied upon by New- 
berry for distinguishing the so-called S. meter opt erus consisted in 
a supposed relatively greater depth of body — "the fusiform and 
slender fish standing for /. fultus, and the broader one for /. 
macropterus." Curiously enough, it has been shown by Dr. 
Eaton, after a study of Newberry's originals in the American 
Museum of Natural History, that whereas one of the specimens 
of S. macropterus in its compressed and flattened condition is 
deeper than a type of S. fultus, all the others are proportionately 
more slender. 1 J. H. Redfield, after advocating the suppression 
of the name "macropterus," remarks that S. fultus is specially 
characterized by the length of the dorsal and anal fins, which 
are even longer than in S. tenuiceps. 2 A comparison of text Fig- 
ures 12 and 13 will enable one to appreciate the differences as 
regards structure of the dorsal fin in this species and S. microp- 
terus. In Plate IX. of this report is given a photographic repro- 
duction of one of Newberry's originals. 

This is the most abundant of all the New Jersey species, and in 
the Connecticut Valley Trias is only inferior numerically to the 
ubiquitous S. tenuiceps. The average length is stated by New- 



1 Amer. Journ. Sci. [4], vol. xv., p. 262. 

*Cit.j Newberry, Monogr. U. S. Geol. Surv., vol. xiv. (1888), p. 35. 



86 ANNUAL REPORT OF 

berry to be about six inches, the extreme of eight inches being 
only rarely attained. 

Semionotus tenuiceps (Agassiz). 

183S-36. Eurynotus tenuiceps, L. Agassiz, Poiss. Foss., vol. ii., pt. i., pp. 159, 

303, pi. xiv. c, Figs. 4, 5. 
1837. Palceoniscus latus, J. H. Redfield, Ann. Lyceum Nat. Hist., N. Y., vol. 

iv., p. 38, pi. ii. 
1837. Eurynotus tenuiceps, J. H. Redfield, ibid., p. 39. 

Eurynotus tenuiceps, E. Hitchcock, Geol. Mass., vol. ii., p. 459, pi. xxix., 

Figs. 1, 2. 
Palceoniscus latus, W. C. Redfield, Amer. Journ. Sci., vol. xli., p. 25. 
Ischypterus latus, Sir P. Egerton, Quart. Journ. Geol. Soc, vol. vi., p. 10. 
Eurinotus ceratocephalus, E. Emmons, Amer. Geology, pt. 6, p. 144, 

pi. ix a. 
Eurinotus ceratocephalus, E. Emmons, Manual Geologjr, ed. 2, p. 188, 

Fig. 164. 
Ischypterus latus, R. H. Traquair, Quart. Journ. Geol. Soc, vol. xxxiii., 

P- 559- 
Ischypterus tenuiceps, J. S. Newberry, Monogr. U. S. Geol. Surv., vol. 

xiv., p. 32, pi. v., Figs. 1-3; pi. vii., Fig. 3. 
Ischypterus latus, J. S. Newberry, ibid., p. 46, pi. liii., Fig. 3. 
Allolepidotus americanus, W. Deecke, Palaeontogr., vol. xxxv., p. 114. 
Semionotus tenuiceps, A. S. Woodward, Cat. Foss. Fishes Brit. Mus., 

pt. iii., p. 59. 
Semionotus tenuiceps, W. H. Hobbs, 21st Rept. U. S. Geol. Surv., pt. 

iii., p. 56 (11011 pi. 4). 
Semionotus tenuiceps, G. F. Eaton, Amer. Journ. Sci. [4], vol. xv., 

P- 295. 



1841 

1841 
1850, 

1857 

i860 
1877 



1888 
1889 

1895 

1901 
1903 



A species attaining a total length of about 20 cm., and readily 
distinguished from all others (except in young stages) by the 
excessive development of the dorsal ridge-scales ; these are very 
large and conspicuous, and, in mature individuals, comparatively 
obtuse. The anterior dorsal outline is considerably arched, 
usually forming a characteristic "hump" immediately behind the 
head. Length of head and opercular apparatus less than the 
maximum depth of the trunk, and contained four times in the 
total length of the fish. Fins as in S. fultus. Scales smooth 
and serrated, those of the middle of the flank in part twice as 
deep as broad. The dorsal ridge-scale immediately in advance 
of the dorsal fin has its posterior border obtuse, and not pro- 
duced, and the corresponding ridge-scale in front of the anal fin 



THE STATE GEOLOGIST. 87 

is notched behind. Ribs more strongly developed than in any 
•other species. 

It is usually possible to determine this form with great facility, 
even in the case of fragmentary remains, none of the other species 
having the back so much elevated immediately behind the head, and 
set along the middle with such long, thickened, distally pointed 
or clavate scales. The ribs are also more conspicuous than in 
most other species, their curved outlines showing sometimes even 
when covered with scales. Owing to> the frequency with which 
this species has been illustrated, and impossibility of mistaking it 
amongst collections, it has not been considered necessary to 
figure it in the present report. 

S. tcnuiceps outnumbers all other species in the Connecticut 
Valley Trias, and is tolerably abundant also in New Jersey. At 
Turners Falls and at Sunderland, Mass., it is especially common, 
probably more than one-half of the individuals derived from the 
latter locality pertaining to this form. 

Semionotus micropterus (Newberry). 

(Plate II, Figs. 6-8, n, 13.) 

1888. Ischyptcrus micropterus, J. S. Newberry, Trans. N. Y. Acad Sci., vol. 

vi., p. 127 (name only). 
1888. Ischypterus micropterus, J. S. Newberry, Monogr. U. S. Geol. Surv., 

vol. xiv., p. 31, pi. iv., Figs. I, 2; pi. xii., Fig. 2. 
1893. Ischypterus newberryi, S. W. Loper, Pop. Sci. News, p. 
1903. Semionotus micropterus, G. F. Eaton, Amer. Journ. Sci. [4], vol. xv., 

p. 263, pi. v., Figs. 6-8. 

D. 8;C. 15; A. 8. 

A regularly fusiform species attaining a total length to the 
base of caudal fin of about 20 cm., the maximum depth occurring 
in the pectoral region and not exceeding 8 cm. The dorsal and 
ventral contours are more strongly convex than in >S\ fultus, but 
the relative position and size of the fins are about the same in 
the two species. Dorsal, anal and pectoral fin-fulcra relatively 
shorter than in S. fultus. Apparently three dorsal fin-fulcra 
originate on the dorsal line over the interneurals. The fifth 
dorsal fulcrum has its origin on the anterior margin of the an- 



88 ANNUAL REPORT OF 

terior ray at a considerable distance from its base, and is about 
one-third as long as the anterior fin-margin (Fig. 13). Pec- 




Fig. 13. 
Semionotus micropterus (Newb.). Fulcra and anterior rays of dorsal fin. 

torals with upwards of 20 fulcra. Ridge-scales moderate, spini- 
form, the one immediately in advance of the dorsal fin slightly 
produced into a point behind. Scales frequently serrated, those 
below the lateral line on the flanks tending to become bi- or tri- 
dentate on the postero-inferior angle (text-fig. 13). 

According to Newberry, the most striking diagnostic charac- 
ters of this species are "its pointed rostrate, depressed muzzle; 
conical narrow head, horizontal below ; the wedge-shaped outline 
of the body, which is widest near the head ; the small and delicate 
fins, and the narrow and oblique tail." The maximum size 
attained by this species, as stated by the same authority, is "ten 
and one-half inches long by three and one-half inches wide, the 
smallest * * * only about three and one-half inches long." 
The fin and scale characters have been worked out in detail by Dr. 
G. F. Eaton, from whose paper the illustrations given in Plate II. 
are borrowed. 

This species is known only from Connecticut, and is stated by 
Newberry to be especially common in the vicinity of Durham. It 
is possible that the detached head figured by Schellwien, in Plate 
III., fig. 4, of his memoir belongs to the species in question, this 
being one of the few T in which the cheek plates are granulated. 



THE STATE GEOLOGIST. 89 

Semionotus Uneatus (Newberry). 
(Plates X., XL) 

1888. Ischypterus Uneatus, J. S. Newberry, Trans. N. Y. Acad. Sci., vol. vi., 

p. 127 (name only). 
1S88. Ischypterus alatus, J. S. Newberry, ibid., p. 127 (name only). 
1888. Ischypterus alatus, J. S. Newberry, Monogr. U. S. Geol. Surv., vol. xiv., 

p. 37, pi. viii., Figs. 1, 2. 
1888. Ischypterus Uneatus, J. S. Newberry, ibid., p. 40, pi. xi., Figs. 1, 2. 

The original description of this species is as follows : 
"Fishes six to eight inches in length ; outline, when perfectly 
preserved, uniformly arched above and below; head relatively 
large, contained about four times in the entire length, broadly con- 
ical in outline ; fins all large ; fulcra arched ; scales of dorsal line 
spinous and strong, but less developed than in I. tenuiceps; ribs 
and interspinous bones frequently preserved ; scales on sides thick 
and strong, arranged in continuous rows from the head backward, 
so as to give a lined appearance, which has suggested the specific 
name." 

It will be observed that the above diagnosis applies to robust 
and comparatively large-sized fishes, with thick scales and strong 
fins and ribs. Distinctive characters, by which the species can be 
readily separated from others accompanying it in the same forma- 
tion, are not embraced in this general definition. For instance, 
nothing is stated in regard to the fulcra, except that they are 
"arched" ; their number, and likewise that of the fin-rays, is not 
given in the text, nor is it apparent from the figures, and it is evi- 
dent that one of the latter has been more or less restored. In a 
word, the species has not yet been adequately defined, and on 
inquiring in what light Newberry viewed its relations to other 
species, we find that he was considerably perplexed over their 
distinction. In one place, for instance, it is stated by him 1 that 
"the fishes of this group [referring to S. Uneatus] are not easily 
separated from some of their associates, some individuals re- 
sembling those of /. lenticularis ; but in these latter the outline is 
more symmetrical, the fins smaller, the scales more delicate, par- 



1 Monogr. U. S. Geol. Surv., vol. xiv. (1889), p. 40. 



90 ANNUAL REPORT OF 

ticularly those of the dorsal line. On the other hand they ap- 
proach through the smaller individuals the group to which I have 
given the name of /. elegans; but these latter are smaller, the 
arch of the back is higher, the head more depressed and acute, 
the fins and scales, are more delicate. Still another variety, in- 
cluding the narrower forms, comes nearer to I. fultus. On the 
whole, however, this group of long, ovoid fishes, from two to 
three inches wide, are distinguishable at a glance from those 
which have the narrow lanceolate outlines of I. fultus." 

At the close of his general remarks on the genus Ischypterus, 
on page 27 of his Monograph, Newberry makes the following 
significant statement : "In the following pages, so far as I have 
been able, I have enumerated and defined all the species of the 
genus which have come under my observation. I deem it neces- 
sary to say, however, that future observations will probably 
diminish rather than increase the number of forms in which the 
differences should be given specific value. For example, /. alatus 
may prove to be only a variety of /. lineatus, and I. modestus a 
phase of /. elegans; but with marked differences and without 
connecting links, so> far as yet observed, it has seemed to me 
hardly justifiable without further evidence of identity to unite 
them under a common name." 

Amongst the species admitted by Newberry to bear a close 
resemblance to »S\ lineatus, his so-called S. alatus approaches it 
so closely as to have created doubt in the author's mind whether 
it was really distinct from the form under consideration. His 
remarks on this subject are as follows: "The fishes to which 
I have given the name of Ischypterus alatus, and have repre- 
sented in PI. VIII., are perhaps most like those under considera- 
tion [S. lineatus], and I have hesitated long before separating 
them; indeed it is probable they will be found to run into' each 
other, so- that they must be regarded as varieties of one species." 
Not only was their founder sceptical as to> a distinction between 
S. lineatus and S. alatus, but no one else who' has examined his 
types has been able to' discover essential differences between them. 
They are here regarded as identical, and it may be further stated 
that the resemblance between S. lineatus and S. elegans is such as 
to excite suspicion lest we have not to do in the one case with 



THE STATE GEOLOGIST. 91 

the adult, and in the other with immature forms belonging- to 
one and the same species. 

Little can be added to the definition already given of 5. line-* 
atus } for the reason that no further satisfactory material has 
come to light. In determining fragmentary individuals, the 
chief features to be relied upon are first of all the dorsal and anal 
fin-fulcra, which form a fringe fully as wide at the base as in 
S. oz'atus, are as strongly curved as in that species, and are 
relatively longer. The moderately deep trunk, conspicuous ribs, 
and minor scale characters are also of service in distinguishing 
these fishes from other members of the same fauna. 

Semionotus elegans (Newbeny). 

(Plate XII.) 

1888. Ischypterus elegans, modestiis, lenticularis, J. S. Newberry, Trans. N. 

Y. Acad. Sci., vol. vi., p. 127 (names only). 
18S8. Ischypterus elegans, J. S. Newberry, Monogr. U. S. Geol, Surv., vol. 

xiv., p. 37, pi. vii., Fig. 2 ; pi. x., Fig. 1 ; xiv., Figs. 1,2. 
1888. Ischypterus modestns, J. S. Newberry, ibid, p. 38, pi. ix., Figs. 1-3. 
1888. Ischypterus lenticularis, J. S. Newberry, ibid, p. 39, pi. x., Figs. 2, 3. 

D. 11 ; C. 15 ; A. 7. Lat. line scales about 32 (fide Newberry). 

A species of slightly smaller size than the preceding, and. dis- 
tinguished from it only by its fin and scale characters. Dorsal 
fin arising at mid-length, with 12 fulcra, which are shorter and 
more closely appressed than in ,S\ lineatus. Anal fin not extend- 
ing to the base of the tail, with about 10 fulcra. Squamation 
regular, firmly united, and hence usually preserved intact; num- 
ber of scales along the lateral line about 32, in transverse rows 
at widest part of trunk about 20; ridge-scales in advance of the 
dorsal fin 18-20, moderate in size; the hindermost ridge-scale 
shield-shaped, not emarginate posteriorly. Dorsal and ventral 
outlines symmetrically arched, but rapidly contracting behind the 
median fins to a depth equal only to about half that of the middle 
of the trunk. 

It will be noticed in the above synonymy that three of New- 
berry's species are united under one head. The propriety of this 
arrangement is self-evident, there being absolutely no characters 



92 ANNUAL REPORT OF 

for distinguishing them from one another. This was virtually 
acknowledged by Newberry, as the following extracts show, al- 
though through hesitancy he maintained their formal separation. 
Under the description of 5. elegans we read : 

"This is the neatest species of the genus known to me; the 
curves of the outline of the body are graceful, the scaling 
crowded but exact. In form it most nearly resembles /. lineatus, 
but is smaller and broader, the back more distinctly and regularly 
arched, and the scales more numerous." As to the affinities of 
the so-called 5". modestus, Newberry remarks : "The fishes most 
nearly allied to these are those which I have included under the 
name of /. elegans, and it is perhaps not certain they should be 
regarded as distinct," and finally, under the head of "Ischypterus 
lenHcularis," it is stated : "The relation between these smaller 
ovoid fishes is rather to those to which I have given the name 
/. elegans, and here the differences may be those of age or sex.- 
The group designated by the latter name consists of fishes which 
are much smaller, often not much more than half the length and 
breadth, the lower line of the body being nearly straight, the 
upper highly arched before the dorsal fin, concavely narrowed 
behind. Hence I have supposed that they constitute a distinct 
species." 

There is still further proof of Newberry's indecision in this 
matter. Examination of the co-types of his so-called S. modcstus, 
now preserved in the American Museum of Natural History 
in New York, shows one of them to bear an original label 
in Newberry's handwriting, which reads as follows : "Isch. 
modestus. — Perhaps only a variety of Isch. elegans N., but 
having a broader and more rounded head, stronger fins, and 
larger and thicker scales. — J. S. N." The scant importance of 
these characters can be appreciated on comparing the figure of 
this specimen, which is given at the bottom of his Plate IX, with 
the figures properly referred to S. elegans. 

Anyone who attentively examines a large series of Boonton 
fishes, and attempts to identify the more slender and elegantly 
fusiform species according to Newberry's ideas, will appreciate 
the difficulties presented by the wide range of effects produced by 
distortion, faulty preservation, and individual variation. The 



THE STATE GEOLOGIST. 93 

contour of the head, curvature of the dorsal and ventral margins 
(within certain limits), and slight differences in the thickness 
and obliquity of the squamation, will come to be regarded as 
characters of minimum importance; and in the present instance, 
absolutely valueless for discriminating between vS\ elegans, S. 
modestus and S. lenticularis. In Plate XII we have refigured one 
of Professor Newberry's originals. 

Semionotiis brauni (Newberry). 

1886. Palceoniscus latus, L,. P. Gratacap, Amer. Nat., vol. xx., p. 243, text- 
fig, {err ore). 

1888. Ischypterus brauni, J. S. Newberry, Trans. N. Y. Acad. Sci., vol. vi., p. 
127 (name only). 

1888. Ischypterus brauni, J. S. Newberry, Monogr. U. S. Geol. Surv., vol. xvi., 
p. 43, pi. xii., Fig. 3, pi. xiii., Figs. I, 2. 

A small species, attaining a total length to the base of caudal 
fin of about 10 cm., in which the length of the head and oper- 
cular apparatus is contained in a little more than three times. 
Cranial bones granulated. Fins small, with delicate fulcra and 
rays ; dorsal and anal remote, the latter extending to the base 
of the caudal. Scales rhomboidal or quadrangular, remarkably 
uniform in size over the greater part of the trunk. Dorsal ridge- 
scales small, anteriorly rounded, and terminating in a short, 
pointed prolongation behind. 

This small and imperfectly known species occurs at a horizon 
several thousand feet lower than that of Boonton, being limited 
to the base of the Triassic system in New Jersey. The partic- 
ulars of its occurrence are thus indicated by Newberry : "The 
only locality from which fishes of the present species have been 
obtained is Weehawken, N. J. Here, beneath the trap of the 
Palisades, is a stratum of highly metamorphosed slate which was 
once a bituminous shale, but which has been baked by the effu- 
sion of the great mass of molten matter above it; the fishes are 
found in this slate. In some layers it also contains great num- 
bers of bivalve crustaceans (Bstheria), which would seem to 
indicate that it was deposited in brackish water." 



94 ANNUAL REPORT OF 

DOUBTFUL SPECIES. 

A number of small forms, some of them no doubt representing 
the young of different species, have been described from the Con- 
necticut Valley and from New Jersey, but owing to one cause or 
another, such as faulty preservation, inadequate description, or 
subsequent injury to or loss of the type-specimens, the names 
which have been proposed for them cannot be said to rest 
upon a secure foundation. In this category may be placed 
the so-called "Ischypterus parvus" founded upon a figure pub- 
lished in Hitchcock's Geology of Massachusetts in 1835 > "Ischyp- 
terus minutus" Newberry, from Durham, Connecticut; "Ischyp- 
terus newberryi" Loper, also' from Durham ; and "Ischypterus 
beardmorei" Smith, from Boonton. The last name was pro- 
posed without definition for a specimen figured in the Metro- 
politan Magazine for October, 1900 (p. 502). Except for its 
small size, the original (which belongs to Mr. G. C. Berrien, of 
Upper Montclair) is suggestive of Semionotus ovatus. Mr. 
Loper' s species is considered by Dr. Eaton to be identical with 
S. micro pterus. 

Genus Acentrophus Traquair. 

Trunk fusiform ; teeth slender. Fins small, with very large 
fulcra; dorsal fin short, opposed to the space between the anal 
and the pelvic pair; caudal fin symmetrical, slightly forked. 
Scales rhombic, smooth or feebly ornamented ; no enlarged dorsal 
ridge-scales ; the scales of the flank not much deeper than broad, 
and those of the ventral aspect nearly equilateral. 

It will be noticed that the only trenchant distinction between 
this genus and Semionotus consists in the absence of enlarged 
ridge-scales. 

Acentrophorus chicopensis Newberry. 

1888. Acentrophorus chicopensis, J. S. Newberry, Monogr. U. S. Geol. Surv., 
vol. xiv., p. 69, pi. xix., Figs. 3, 4. 

Under this name are described certain fishes of moderate size 
("six inches long by one and one-half inches wide," according 



THE STATE GEOLOGIST. 95 

to Newberry)-, which are too imperfectly preserved for satis- 
factory determination or definition. They have been obtained 
from but a single locality, in rather coarse sandy shales near 
Chicopee Falls, Mass., which have been considerably metamor- 
phosed by igneous agencies. This circumstance, as stated by 
Newberry, "has obscured some of the details of structure, such 
as the surface of the scales, the shape and markings of the head- 
bones, etc., but has left the outlines of the body and the position 
and form of the fins distinctly visible. The most striking char- 
acters of these fishes are the narrow wedge-shaped form of body, 
the straightness of the dorsal and ventral lines, the smallness 
of the fins, the posterior position of the dorsal, and the rounded 
and unarmed margins of the median dorsal scales." Assuming 
the correctness of the generic determination, this is the only 
species of Acentrophorus which has yet been recognized in this 
country. 

Family CATOPTERID^. 

Genus Catopterus Redfield (Redfieldius Hay). 

Trunk elegantly fusiform, head relatively small, tail hemi- 
heterocercal. External bones more or less ornamented with 
ridges and tubercles of ganoine; no median series of cranial roof 
bones. Fins of moderate size, consisting of robust rays, more 
or less enameled, and distally bifurcated; fulcra well developed, 
short and closely set. Dorsal and anal fins triangular, the 
origin of the former behind that of the latter ; caudal fin forked. 
Scales large or of moderate size, nearly or quite smooth, and 
serrated along their postero-inferior margin; dorsal ridge-scales 
not much enlarged. Teeth numerous, small, acutely conical. 

This is an exclusively American genus, although a closely 
allied form, Dictyopyge, occurs in both Europe and America. 
These two genera constitute a family by themselves, Catopteridcs, 
which is evidently descended from the ancient PalcEoniscidce, the 
group from which modern sturgeons and paddle-fishes are 
also derived. The structure of the head and shoulder-girdle has 
not yet been worked out for these two Triassic genera, but they 



96 ANNUAL REPORT OF 

have a general Palseoniscid aspect, the eye being far forwards, 
snout prominent, and gape of the mouth wide. In this short- 
lived family, also, specialization had not advanced so far as to 
result in the correlation of the dermal rays of the unpaired fins 
with their endoskeletal supports, and the scales are all rhombic 
and ganoid, as in the more ancient types. 

Remains of Catopterus are on the whole less abundant than 
those of the accompanying genus Semionotus, both in New Eng- 
land and New Jersey, and as a rule are less perfectly preserved. 
Nevertheless, the characters presented by the former genus are 
so well marked and distinctive that there is seldom any diffi- 
culty in determining even the most fragmentary individuals. 
The most obvious peculiarity of the genus consists, as the name 
implies, in the remote position of the dorsal fin. In Semionotus 
the dorsal is always anterior to the anal, in Catopterus it is either 
opposite or posterior. The margins of all the fins are thickly set 
with fine fulcra, and present in consequence a delicately fringed 
appearance, and the fin-rays themselves are very numerous, finely 
articulated, and enameled. Other noticeable differences con- 
sist in the ornamented condition of the cranial bones, and serra- 
tion of the hinder margin of the scales. 

Although the genus Semionotus is represented in this country 
by half a dozen or more species, only two of Catopterus can be 
definitely recognized. These are C. gracilis Redfield and C. Ted- 
Heidi Egerton, both founded on large and nearly complete fishes 
which differ from one another chiefly in the proportions of body 
proportions and scale characters. The so-called C. parvulus 
Redfield is probably to be regarded as the young of C. gracilis. 
Catopterus minor and C. ornatus Newberry are supposed to stand 
in a similar relation to C. rediieldi. 

Catopterus gracilis J. H. Redfield. 

(Plate XIII.) 

1837. Catopterus gracillis, J. H. Redfield, Ann. Lyceum Nat. Hist., N. Y., vol. 

vol. iv., pp. 37-39, pl- i- 
1841. Catopterus gracilis, W. C. Redfield, Amer. Journ. .Sci., vol. xli., p. 27. 
Catopterus gracilis, J. S. Newberry, Monogr. U. S. Geol. Surv., vol. xiv., 
p. 55, pl. xvi., Figs. 1-3. 



THE STATE GEOLOGIST. 97 

1S95. Catopterus gracilis, A. S. Woodward, Cat. Foss. Fishes Brit. Mus., pt. 

iii., p. 2. 
1901. Semionotus fultus, W. H. Hobbs, 21st Ann. Rept. U. S. Geol. Surv., 

pt. iii., p 56, pi. 4, Fig. B (errore). 

The type species, attaining a total length of about 25 cm. 
Length of head with opercular apparatus about equal to- the max- 
imum depth of trunk, and contained five times in the total length 
of the fish; depth of caudal pedicle somewhat less than one-half 
that of the abdominal region. Cranial bones finely granulated. 
Pelvic fins arising about midway between the pectorals and anal ; 
dorsal and anal fins subequal in size, and almost completely op- 
posed. Scales smooth, none deeper than broad, those of the 
flank in the abdominal region very finely serrated. 

The fin-formula for this species as given in the original 
description by J. H. Redfield is as follows : 

D. 10-12; C. 30-40; A. 20-30; V. circa 8; P. 10-12. 

In the additional notes on this form given by the elder Red- 
field, it is stated that "the pectoral fins are of an elongated form, 
and are strengthened on the anterior margin by one or two large 
and partly flattened rays, to the front of which the fringe of 
fine ray lets [fulcra] is attached. Owing to- this peculiarity of 
structure, the smallest section of the pectoral fin will often serve 
to identify this species." 

Ordinarily there is little question as to what constitutes the 
type of a species. In the present instance, the original descrip- 
tion is founded upon characters exhibited by four or five typical 
specimens, one of which is figured in Plate I. of Redfield's paper. 
This last specimen was stated to be in the possession of the Yale 
Natural History Society at New Haven, and is now preserved in 
the Peabody Museum of Yale University. The present where- 
abouts of the remaining co-types are unknown, hence the figured 
specimen at Yale is the only -authentic example now in evidence 
that has served for the establishment of this species. Professor 
Newberry, who examined it during the preparation of his Mono- 
graph, concluded that it possessed a greater depth of trunk than 
is normal for this species, and proposed its transfer to C. red- 
Heidi, Egerton. This procedure could only be justified in case 
7 GEOL 



98 ANNUAL REPORT OF 

it were shown that the example in question displayed characters 
irreconcilable with the definition of C. gracilis, or differed beyond 
the limits of individual variation from the other typical specimens 
referred to in the original description. But neither of these 
requisite conditions has been fulfilled, nor apparently can they 
be, hence we may continue to regard Redfield's figured specimen 
as one of the authentic co-types of this species. It is to be hoped 
that its characters may be critically re-investigated, and in partic- 
ular the details of its cranial osteology made known, since in this 
specimen the head-structure is unusually well displayed. It is 
observed by Newberry that "unfortunately the head bones are 
not only generally displaced, but they are covered with a coat- 
ing which obscures the sutures, the matrix clinging to the gran- 
ulated surfaces of the head bones much more closely than to 
the polished scales." 

This species occurs at Boonton and at various New England 
localities, being especially abundant at Durham. The Connecti- 
cut Valley material is as a rule better preserved than that of New 
Jersey. 

Catopterus redfieldi Egerton. 

1847. Catopterus redAeldi, Sir P. Egerton, Quant. Journ. Geol. Soc, vol. Hi., 

p. 278. 
1888. Catopterus redfieldi, J. S. Newberry, Monogr. U. S. Geol. Surv., vol. 

xiv., p. 53, pl. xv., Figs. 1-3. 
1895. Catopterus redfieldi, A. S. Woodward, Cat. Foss. Fishes Brit. Museum, 

pt. iii., p. 3. 

"A broader species than the preceding [C. gracilis], and with 
scales not so long in proportion to their depth." — Egerton. 

The above definition has been supplemented by a number of 
diagnostic characters pointed out by Newberry, and incorporated 
by him into a precise description, which has been condensed by 
Smith Woodward as follows : 

"A comparatively robust species as large as the type. Length 
of head with opercular apparatus not more than two-thirds as 
great as the maximum depth of the trunk, and contained nearly 
six times in the total length of the fish; depth of caudal pedicle 



THE STATE GEOLOGIST. 99 

equaling about one-third that of the abdominal region. Cranial 
bones finely granulated. Pelvic fins arising midway between the 
pectorals and the anal; dorsal and anal fins nearly equal in size, 
and the former arising opposite to the middle of the latter. Scales 
mostly smooth, but sometimes in part longitudinally striated, 
the striae terminating in the coarse serrations of the posterior 
border which characterize the principal flank-scales; many of the 
flank-scales deeper than broad." 

The distribution of this species is identical with that of its 
congener, and, like the latter, it is more abundant at Durham than 
elsewhere. 

Genus Dictyopyge Egerton. 

Distinguished from Catopterus only by the more anterior posi- 
tion of the dorsal fin, which never arises behind the origin of 
the anal. 

Dictyopyge macrura W. C. Redfield. 

1841. Catopterus macrurus, W. C. Redfield, Amer. Journ. Sci., vol. xli., p. 27. 
1847. Dictyopyge macrura, Sir P. Egerton, Quart. Journ. Geol. Soc, vol. iii., 

p. 276, pi. viii., pi. ix., Fig. I. 
1857. Catopterus macrurus, W. C. Redfield, Proc. Amer. Assoc. Adv. Sci. 

1856, pt. ii., p. 186. 
1888. Dictyopyge macrura, J. S. Newberry, Monogr. U. S. Geol. Surv., vol. 

xiv., p. 64, pi. xviii., Figs. 1, 2. 
1895. Dictyopyge macrura, J. S. Newberry, A. S. Woodward, Cat. Foss. 

Fishes Brit. Museum, pt. iii., p. 4, text-fig. 1. 

A species attaining a total length of about 15 cm. Length of 
head with opercular apparatus somewhat less than the maximum 
depth of the trunk, and contained nearly five times in the total 
length of the fish; depth of caudal pedicle less than one-half of 
that of the abdominal region. Cranial bones externally orna- 
mented with fine granulations. Pelvic fins arising midway be- 
tween the pectorals and anal fin ; dorsal at least as high as long, 
arising slightly in advance of the anal and nearly as large as the 
latter; anal with about 30 rays, and extending almost to the 
base of the caudal fin. Scales smooth, not serrated. 



ioo ANNUAL REPORT OF 

This species is not represented in New Jersey, being confined, 
so far as known, to the Triassic Coal-field of Virginia. 

Family EUGNATHID^. 

Trunk fusiform or elongate, not much laterally compressed. 
Cranial and facial bones moderately robust, externally enameled, 
and opercular apparatus complete ; gape of mouth wide, snout not 
produced, marginal teeth conical, and larger than the inner teeth. 
Fin-rays robust, articulated, and distally divided fulcra con- 
spicuous. Dorsal fin short and acuminate. Scales rhombic, 
sometimes with rounded posterior angles. 

Genus Ptycholepis Agassiz. 

Trunk elegantly fusiform; snout acutely pointed and promi- 
nent; external bones highly ornamented with prominent ridges; 
marginal teeth very small and regular; dorsal fin in advance of 
anal, caudal fin forked; scales all narrow and elongate, marked 
with deep longitudinal grooves. Fulcra biserial, conspicuous on 
all the fins excepting the dorsal. 

Ptycholepis marshi Newberry. 

1878. Ptycholepis marshi, J. S. Newberry, Ann. N. Y. Acad. Sci., vol. i., p. 

127. 
1888. Ptycholepis marshi, J. S. Newberry, Monogr. U. S. Geol. Surv., vol. 

xiv., p. 66, pi. xix., Figs. 1, 2. 
1895. Ptycholepis marshi, A. S. Woodward, Cat. Foss. Fishes Brit. Museum, 

pt. iii., p. 324. 

A species of slender proportions, attaining a length of about 
20 cm. Head with opercular apparatus occupying somewhat less 
than one-fourth the total length of the fish. Ornamental rugse 
of cranial roof slightly radiating; those of the facial and oper- 
cular bones more or less parallel and forked. Dorsal fin far 
forwards, and pelvic fins arising opposite its hinder extremity. 
Scales exhibiting only longitudinal ridges and furrows, and the 
hinder border often deeply serrated. (Woodward). 



THE STATE GEOLOGIST. 101 

No indications of this species have yet been discovered in New 
Jersey. The dozen or so examples which have been obtained were 
all derived from the Newark series of Durham, Connecticut. 



Order CROSSOPTRRYGH. 

Family COELACANTHID^. 

Body deeply and irregularly fusiform, with cycloidal, deeply 
overlapping scales, more or less ornamented with ganoine. 
Branchiostegal apparatus between the mandibular rami consist- 
ing of a pair of large gular plates. Paired fins obtusely lobate; 
two dorsal fins, the anterior without baseosts, the posterior dor- 
sal and the anal with baseosts, obtusely lobate. Axial skeleton 
extending to the extremity of the caudal fin, usually projecting 
and terminated by a small supplementary caudal. Air-bladder 
ossified. 

Genus Dipujrus Newberry. 

Supplementary caudal fin prominent, with much elongated 
pedicle; fin-rays robust, closely articulated in the distal half; pre- 
axial rays of the first dorsal and caudal fins with spinous 
tubercles. Scales and head-bones irregularly striated. 

Dipluras longicaudahis Newberry. 

1878. Diplurus longicaudatus, J. S. Newberry, Ann. N. Y. Acad. Sci., vol. i., 

p. 127. 
1888. Diplurus longicaudatus, J. S. Newberry, Monogr. U. S. Geol. Surv., 

vol. xiv., p. 74, pi. xx. 

The type and only known species, attaining a total length of 
about 70 cm. to the tip of the supplementary caudal fin, and maxi- 
mum depth of trunk of about 20 cm. Anterior dorsal fin strong, 
supported by a single large laminar axonost ; the lobate posterior 
dorsal nearly opposite the anal, and corresponding to' it in form 
and size; caudal fin much elongated, and separated from the 
supplementary caudal by a distinct interval; paired fins obtusely 
lobate; scales large cycloidal, and deeply overlapping; the ex- 



102 ANNUAL REPORT OF STATE GEOLOGIST. 

posed portion marked with fine longitudinal rugae; teeth un- 
known. 

This large Crossopterygian is of extremely rare occurrence, 
being known only by five specimens, two of which were obtained 
from Boonton, and the remainder from Durham, Connecticut. 
All of these specimens are now preserved in the American 
Museum of Natural History, in New York. 



Explanations of Plates* 



(103) 



PLATE I. 

Semionotus agassisii (W. C. Redfield). Newark series; Sunderland, Mass. 
Lateral aspect of nearly perfect specimen belonging to the American 
Museum of Natural History, New York, X x /2. 

(104) 



PLATE I. 




X 



« 



PLATE II. 

Fig. i. Semionotus fultus (Ag.). Dorsal fin. 
" 2. " " Pectoral fin. 

3- Anterior flank scales. 

4- Posterior flank scales. 

" 5. Semionotus agassizii (W. C. Redf.). Scales from the twelfth longi- 
tudinal row, a little below the lateral line. 

" 6. Semionotus micropterus (Newb.). Pectoral fin. 

7- Anterior flank scales. 

8. Posterior flank scales. 

" 9. Semionotus agassizii (W. C. Redf.). Posterior flank scales show- 
ing "pegs." 

" 10. Semionotus agassizii (W. C. Redf.). Hindermost scale of anterior 
dorsal ridge. 

" 11. Semionotus micropterus (Newb.). Hindermost scale of anterior 
dorsal ridge. 

" 12. Semionotus agassizii (W. C. Redf.). Scales of the seventh and 
eighth longitudinal rows, immediately below the lateral line. 

" 13. Semionotus micropterus (Newb.) Dorsal fin. 

All the figures of Plate II. are of twice the natural size, and drawn by Dr. 
G. F. Eaton from specimens belonging to the Yale Museum. (See American 
Journal of Science, vol. xv., April, J003.) 



(106) 



PLATE II. 






8 9 



10 



ft 




A 





\)a 



I 



11 



i ( 




12 




PLATE III. 

Fig. I. Semionotus agassisii (W. C. Redf.). Head, natural size. 

Fr, frontal; Pa, parietal; S.t, supratemporal; Sq, squamosal; P. or, 
postorbital; Op, operculum; P. op, preoperculum; Lop, interopercu- 
lum; S.op, suboperculum. 
" 2. Seminonotus agassisii (W. C. Redf.). Lower flank scale, showing ar- 
ticular process or "peg," natural size. 
" 3. Semionotus sp. Lower flank scales, showing double articula- 
tion. XVi. 
" 4. Semionotus sp. Premaxillse, natural size. 
" 5. Semionotus ovatus (W. C. Redf.). Dorsal fin, twice natural size. 

All the figures of this plate are reproduced after Eaton, loc cit., (1903). 

(108) 



PLATE III. 









PLATE IV. 

Semionotus ovatus (Redf.), X %• 

Small-sized, somewhat distorted individual from Boonton, N. J. State 
Geological Collection. 



(no) 



PLATE IV. 




PLATE V. 

Semionotus ovatus (Redf.). Natural size. 

Imperfect specimen from the Newark series of Boonton, showing char- 
acters of the median' fins. State Geological Collection. 



(112) 



PLATE V. 




8 GEOL 



PLATE VI. 

Semionotus ovatus (Redf.). Natural size. 

Young individual, apparently belonging to this species, similar to those to 
which the name "Isctypterus beardmorei" has been applied. Newark series; 
Boonton, N. J. Original belonging to the State Geological Collection. 



(114) 



PLATE VI. 







PLATE VII. 

Semionotus agassisii (Redf.). Natural size. 

Nearly perfect fish from the Newark series of Sunderland, Massachusetts, 
determined by Professor Newberry as belonging to this species. An outline 
figure of the same specimen is shown of one-half the natural size in Plate I. 
Original preserved in the American Museum of Natural History in New York. 



(116) 











v 



■■■■■■■ 



Semionotus agassizii (Redf.), X i/i. Sunderland, Mas 



PLATE VIII. 

Semionotiis agassizii (Redf. ). Natural size. 

Photographic reproduction of a specimen from the same locality as the last, 
and, like it, belonging to the American Museum of Natural History in New 
York. Dorsal contour and ridge-scales well displayed. 



di8) 




Semionotus agassizii (Redf.), X i/i. Sunderland, Mass. 



PLATE IX. 

Semionotus fultus (Agassiz). Natural size. 

Photographic reproduction of the original specimen figured in Plate VI, 
Fig. 2, of Newberry's Monograph (1888), now preserved in the American 
Museum of Natural History in New York. (Cat. No. 602G). Boonton, N. J. 



(120) 



PLATE IX. 




PLATE X. 

Semionotus lineatus (Newb.) X s /n- 

Imperfect specimen displaying characters of the dorsal and anal fins, and 
showing ossified ribs. Newark series ; Boonton, N. J. - Original belonging to 
the State Geological Collection. 



(122) 



PLATE X. 




PLATE XI. 

Semionotus lineatus (Newb.) X Yi- 

Fragment with the dorsal fin excellently preserved, and showing anteriorly 
notched dorsal ridge-scales. Newark series ; Boonton, N. J. Original belong- 
ing to the State Geological Collection. 

(124) 



PLATE XL 





PLATE XII. 

Semionotus elegans (Newb.). Natural size. 

Photographic reproduction of the original specimen figured in Plate XIV, 
Fig. i, of Newberry's Monograph (1888), now preserved in the American 
Museum of Natural History in New York. (Cat. No. 1516G.) Newark 
series ; Boonton, N. J. 



(126) 



PLATE XII. 




PLATE XIII. 

Catopterus gracilis (Redf.). Natural size. 

Specimen of less than the average size, but with well preserved squamation, 
from the Connecticut Valley Trias. Original belonging to the Museum of 
Comparative Zoology, at Cambridge, Massachusetts. 



(128) 



PLATE XIII. 




9 GEOL 



PLATE XIV. 

Examples of Scmionotus showing effects of mechanical deformation, one 
of them being compressed, and the other elongated, by a force acting in a 
single direction. Newark series ; Boonton, N. J. Original belonging to State 
Geological Collection. 



(130) 



c.<&o< 



PLATE XIV.