(navigation image)
Home American Libraries | Canadian Libraries | Universal Library | Community Texts | Project Gutenberg | Children's Library | Biodiversity Heritage Library | Additional Collections
Search: Advanced Search
Anonymous User (login or join us)
Upload
See other formats

Full text of "Catalogue of the fossil fishes in the British Museum (Natural History) .."



! 







w 




>1 

1 

I PRESENTED 




H MUSEUM. 






■ 


i 
i ■ 



*i* 5 % 

VfAV CATALOGUE 



OF THE 



FOSSIL FISHES 



IN THE 



BRITISH MUSEUM 

(NATUKAL HISTORY), 



CROMWELL ROAD, S.W. 



PART II. 

CONTAINING THE 

ELASMOBRANCHII (ACANTHODII), HOLOCEPHALI, 

ICHTHYODORULITES, OSTRACODERMI, DIPNOI, and 

TELEOSTOMI (CROSSOPTERYGII and CHONDROSTEAN 

ACTINOPTERYGII). 



<* Gill 

aiTHl II SMITH WOODWARD, 
F.G.S., F.Z.^ 



LONDON : 
PRINTED BY ORDER OF THE TRUSTEES. 

SOLD BY 

LONGMANS & Co., 39 PATERNOSTER ROW; 

B. QUARITCH, 15 PICCADILLY; ASHER & Co., 13 BEDFORD STREET, COVENT GARDEN; 

KEGAN PAUL, TRENCH, TRUBNER & Co., 57 LUDGATE HILL; 

AND AT THE 

BRITISH MUSEUM (NATURAL HISTORY), CROMWELL ROAD, S.W. 

1891. 







PRINTED BY TAYLOR AND FRANCIS, 
RED LION COURT, FLEET STREET. 



PREFACE. 



Since the completion of Part I. of this Catalogue in 1889, nearly 
two years have elapsed, during which time great progress has been 
made in the examination and careful study of the Collection of 
Fossil Pishes; while Mr. Arthur Smith Woodward has had the 
additional advantage of visiting the principal Museums of Scandi- 
navia, Russia, Austria, Germany, the United States, and Canada. 
A knowledge of the " types " contained in other Museums is essen- 
tial to a correct interpretation of our own specimens, and much of 
the merit of the present volume may be attributed to this fact, and 
to the wider experience gained by personal interchange of views 
with ichthyologists abroad. 

Special attention has also been paid by the author to the careful 
collation of the very extensive and widely scattered literature of his 
subject, as amply testified by the very copious references which 
occur throughout this Catalogue. 

The present volume commences with the Acanthodii, which are 
shown, by preponderating evidence, to belong to the Elasmobranchs. 
The Chimceroidei come next, the most important forms being those 
of Squalor aja and Myriacanthus ; while Ischyodus and Edaphodon 
are represented by a fine series of jaws. Next follows the very 
large collection of " Ichthyodorulites " (fish-spines) belonging to 
Elasmobranch and Chimseroid fishes, but not definitely placed in 
any group. To these succeed the Ostracodermi, notochordal fishes 
with a well- developed exoskeleton, the head and anterior portion of 

a2 



IV PREFACE. 

the trunk being covered with plates, and the mouth being destitute 
of hard parts. Here are placed the earliest-known fossil fishes, the 
anomalous Pteraspidee and CepJuilaspidce, of which the finest ex- 
amples have recently been presented by George H. Piper, Esq., 
F.G.S., of Ledbury. These are succeeded by the Asterolepida (well 
represented by Pterickthys, Botliriolepis, &c). Then follow the 
Dipnoi, represented by Dipterus, PalcedapJms, Phaneropleuron, 
Ctenodus, Ceratodus, &c. ; and the Artlirodira, proposed to embrace 
the unrivalled collection of Coccosteus, with DinichtJiys, Homostcus, 
Heterosteus, &c. 

The Crossopterygian Teleostoiti come next, with HolojytycMus, 
Rliizodus, Megalichthys, Glyptopomus, and Coelacanthus, with Un- 
dina, Maeropoma, and many others. To these succeed Actino- 
pterygii of the family Pcrtceoniscidce, with Oxygnathus and some 
twenty-five other genera, one of the largest groups represented in 
this Catalogue, and to the determination of which Dr. Traquair has 
devoted so many years of stud}\ The Platysomatidce conclude the 
present volume, with the fine series of Plalysomas, Eurynotus, Chei- 
rodus, &c, from the Permian and Carboniferous strata. 

It is hoped that the sixteen Plates and fifty-eight woodcuts will 
prove of assistance to those using the Catalogue, especially at a 
distance from the Museum Collection, and also enable the student 
in Comparative Ichthyology the better to appreciate the points of 
structure indicated in the text. 

The next volume will contain the modern Chondrostean Acti- 
nopterygii, and the lengthy series of typical Physostomous fishes 
specially characteristic of the Mesozoic and early Tertiary Epochs. 



HENEY WOODWARD. 



British Museum, 

Geological Department 

January 20th, 1891. 



INTRODUCTION. 



There is no more striking instance of the difficulty of interpreting 
fossil remains by a close comparison with the skeletons of existing 
animals, than that presented by the Palaeozoic Fishes. When 
the first fragments of Coccostean plates from the Lower Old Eed 
Sandstone of Caithness were noticed by Sedgwick and Murchi- 
son sixty years ago, nothing more closely similar among existing 
animals could be found than the dermal plates of the mud-tortoises. 
Trionyx was accordingly entered in the list of Caithness fossils \ 
Nearly eight years later, the Eussian geologist Kutorga 2 , when 
attempting to interpret fragmentary teeth and dermal plates from 
the corresponding formations of Livonia, was led to name a long 
series of mud-tortoises, lizards, and Ichthyosauri from that country, 
giving good figures and detailed descriptions of the evidence upon 
which the restoration of so remarkable and unexpected a fauna was 
based. Even when such entirely erroneous impressions were re- 
moved by the discovery of more satisfactory specimens, and when 
the far-reaching researches of the ichthyologist, Louis Agassiz, had 
shown that all these remains pertained to fish-like organisms no 
longer existing, the same tendency to interpret the past by a rigorous 
comparison with the present everywhere prevailed, and the frequent 
result was a distortion of the facts of structure in the fossils to con- 
form to arrangements observed in the present fish-fauna. Not only 
was Hugh Miller induced, by Agassiz's researches, to compare in 
detail the skulls of some of the Old Eed genera with that of the 
living cod-fish 3 , but this recent gadoid was actually used by Agassiz 

1 Trans. Geol. Soc. [2] vol. iii. (1829), p. 144, pi. xvi. fig. 6. 

2 S. Kutorga, ' Zweiter Beitrag zur Geognosie und Palaontologie Dorpat's,' 
1837. 

3 H. Miller, 'Footprints of the Creator,' (1849), p. 48. 



VI INTRODUCTION. 

himself to impart a life-like aspect to tlie head in his restored 
figure of the Dipnoan and Crossopterygian genera Dipterus and 
Diplopterus l . In the interpretation of fins, again, close comparison 
with existing fishes led to some noteworthy fundamental errors, 
such as the restoration of the dorsal fin of Coccosteus 2 , as if it per- 
tained to the most modern specialized type ; and many other cases 
might he cited of an essentially similar character. Quite in modern 
times, indeed, the reiterated association of the Cephalaspidae, Astero- 
lepidae, and Coccosteidae with recent Sturgeons by Owen 3 ; the still 
more elaborate comparison of the Coccosteidae with existing 
Siluroids by Huxley 4 ; and the quite recent adhesion to this Silu- 
roid theory by dewberry 5 — all must now be regarded as resulting 
from too narrow a conception of the limits within which certain 
minor skeletal characters may occur. The ascertained facts of 
embryology and the well-established broad principles of palaeonto- 
logy are now at the disposal of the investigator ; and it is hoped 
that a detailed review of the whole subject, such as is attempted for 
the first time' in the present volume, may tend towards a more 
philosophical understanding of the early representatives of the class 
under consideration. 

The first essential fact requiring special emphasis, at the outset, 
seems to be, that although the Palaeozoic fishes certainly belong to 
the most generalized great divisions of their class, a large proportion 
of the known types are extremely specialized members of these 
divisions. This is clearly indicated by the characters of the fins in 
many forms. Just as in the existing fauna, the most striking 
examples of extreme specialization are comprised within the dominant 
higher groups of Actinopterygian Teleostomi, so in the Palaeozoic 
fauna the same instances of development occur almost exclusively 
in the then dominant orders of the Ostracodermi, Elasmobranchii, 
and Crossopterygian Teleostomi. If in the one case specialization 
proceeds sometimes almost exactly in the same manner as it does in 
the other, everything seems to point to the conclusion that this is 

1 L. Agassiz, ' Poissons Fossiles du Vieux Grres Eouge,' (1844), pi. E. 

2 L. Agassiz, ibid. pi. vi. fig. 3. 

3 E. Owen, ' Paleontology,' ed. 2 (1861), p. 139 ; and ' Anatomy of Verte- 
brates,' vol. i. (1866), p. 12. 

4 T. H. Huxley, " Preliminary Essay upon the Systematic Arrangement of 
the Fishes of the Devonian Epoch " (Mem. Geol. Surv. dec. x. 1861), p. 29. 

5 J. S. Newberry, " Tbe Palaeozoic Fishes of North America " (Mon. U. S. 
Geol. Surv. no. xvi. 1889), p. 141, et passim. 



INTRODUCTION. Vll 

merely an instance of parallel development in the different groups ; 
the same laws prevailing in each great division and producing 
analogous results. 

Such being the case, the difficult question arises as to what cha- 
racters determine the Subclasses (as we prefer to term the great 
divisions), according to the most recent researches. For a long 
period, as is well known, it has been a prevalent custom, at least in 
Europe, to follow the combined arrangements of Cuvier and Agassiz 
as modified by Johannes Miiller 1 . Sharks and Rays, with the 
Uhimaeras, have been generally regarded as an order or subclass, 
variously termed Elasmobranchii, Chondropteryoii, Selachii, or 
Placoidei, and specially characterized (i) by the absence of mem- 
brane-bones or true ossifications of any kind, (ii) by the arrangement 
of the- gills, and (iii) by the characters of the brain, heart, intestine, 
and ovaries. The recent Polyptents, Acipenser, Lepidosteus, and 
Amia have been regarded as typifying four groups, to be comprised 
in an order or subclass Ganoidei ; this agreeing with the Elasmo- 
branchii in the more important visceral characters, though distin- 
guished by the presence of an air-bladder, the small size of the 
numerous ova, and the development of both endoskeletal and exo- 
skeletal ossifications, including a bony gill-cover. The Dipnoi, 
typified by the existing Lepidosiren, Protopterus, and Ceratodus, 
have sometimes been included in the Ganoidei, sometimes (as by 
Miiller) elevated into an equivalent division, on account of their 
approach to the Amphibia ; while the Teleostei, or modern bony 
fishes, with decussating optic nerves, no intestinal spiral valve, and a 
non-contractile bulbus arteriosus to the heart, have constituted the 
highest order or subclass, specially characteristic of the existing fauna. 
Dr. Gunther 2 proceeds further than all the other authors in 
elaborating this scheme of classification, uniting the Elasmobranchii 
and Ganoidei (including the Dipnoi) in a great subclass of 
Paljeichthyes ; this to be equivalent in value to the Teleostei, 
and distinguished solely by the three visceral characters already 
mentioned in connection with the heart, intestine, and optic nerves. 
To emrjhasize the division all the more clearly, the " Palaeichthyes " 



1 J. Miiller, " Ueber den Bau und die Grenzen der Ganoiden und iiber das 
natiirliche System der Fiscke," Abh. k. Akad. Wiss., phys. CI., Berlin, 1844, 
pp. 117-216, with plates. 

2 A. Gunther, Phil. Trans. 1871, p. 554; also ' An Introduction to the Study 
of Fishes '(1880). 



Vlll INTRODUCTION. 

are arranged in ascending series, so far as can be determined., while 
the " Teleostei " are treated in precisely the opposite order. 

This dual subdivision may appear, at first sight, to be the logical 
result of Agassiz's recognition of the primitive nature of the typical 
ft Ganoidei," — especially when added to Miiller's subsequent discovery 
of the important characters these fishes possess in common with the 
Elasmobranchs, Chimaeroids, and Dipnoans. A consideration of the 
researches of Agassiz himself, however, suffices to demonstrate that 
if gradations in skeletal anatomy are more or less concomitant, as 
usual, with the evolution of the soft parts, every essential link be- 
tween the " Ganoidei " and " Teleostei " is already known. So long 
ago as 1866, this fact was clearly recognized by Owen l , when he 
proposed to group the Ganoids and Teleosteans in a subclass Teleos- 
tomi, adopting the Plagiostomi (including Holocephali) and Dipnoi 
as equivalent divisions. About the same time, Kner 2 concluded that 
the group of Ganoidei was not homogeneous, and was, at least in part, 
separated too widely from the Teleosteans by Agassiz. The sub- 
sequent investigations of Cope 3 , Gill 4 , Liitken 5 , and Huxley 6 have 
tended in the same direction ; and the most recent statements of 
the last-named author concerning points of visceral anatomy will be 
generally regarded as final and conclusive. The researches of Boas 
are cited to prove that there is no absolute distinction between 
Ganoids and Teleosteans in the conus arteriosus of the heart; 
the rudiment of a spiral valve in the intestine of Ohirocentrus is 
noticed as rendering a second point of the original Mullerian 
diagnosis invalid ; while a reference to Wiedersheim's discovery 
of the partial decussation of the fibres of the optic nerves 
in some lizards, suggests that if this feature be of little syste- 
matic importance in an order of Reptiles, it is not likely to be 

1 E. Owen, ' Anatomy of Vertebrates,' vol. i. (1866), p. 7. 

2 R. Kner, Sitzungsb. k. Akad. Wiss., math.-naturw. CI. vol. liv. pt. i. (1866), 
pp. 519-536. 

3 E. D. Cope, Trans. Amer. Phil. Soc, n. s., vol. xiv. (1871), pp. 445-460 ; 
Proc. Amer. Assoc. Adv. Sci. 1871 (1872), pp. 317-343 ; Amer. Nat. vol. xix. 
(1885), pp. 234-243; ibid. vol. xx. (1886), p. 1031; ibid. vol. xxi. (1887), 
pp. 1014-1019; ibid. vol. xxiii. (1889), pp. 852-860; Proc. Amer. Phil. Soc. 
1884, pp. 577-585. 

4 T. Gill, Proc. Acad. Nat. Sci. Philad. 1861, pp. 12-20 ; and " Arrangement 
of the Families of Fishes," Smithsonian Miscell. Coll. vol. xi. (1872). 

5 C. Liitken, " TJeber die Begrenzung und Eintheilung der Ganoiden," Palse- 
ontographica, vol. xxii. (1873), p. 1 ; translated from Yidenskab. Meddel. Naturh. 
Foren. Kjobenhavn, 1868. 

6 See especially Proc. Zool. Soc. 1876, pp. 24-59, and ibid. 1883, pp. 137-139. 



INTRODUCTION. IX 

an essential character in the diagnosis of subclasses of Fishes. In 
short, the terms " Ganoid " and " Teleostean," while convenient for 
use in alluding to well-defined hony-scaled types and modern bony 
fishes respectively, can no longer be employed as means of precise 
scientific expression. 

At the same time, however, that modern research has led to these 
difficulties, the combined results of comparative anatomy and palae- 
ontology have suggested an alternative classification, which seems to 
express all the more important facts at present known. It is to be 
expected that any subdivision of a class into " orders " or " subclasses " 
will gradually become less cogent as the earlier types are more 
fully revealed ; but when all discoveries tend to prove that these 
subdivisions are divergent phyla, meeting only in remote antiquity, 
an approximately natural classification seems to have been attained. 
Among fishes, for example, it is now well known that, at least since 
Lower Devonian times, there have been two distinct plans of cranial 
structure, between which no definitely intermediate forms occur. 
As pointed out both by Stannius x and Huxley 2 , the upper segments 
of the mandibular and hyoid arches are directly fused with the 
chondrocranium in Chimcera, Protojzterus, and their allies ; while they 
are loosely articulated, the upper segment of the hyoid arch forming 
a movable suspensorium, in all the Elasmobranchs and the so-called 
Ganoidei and Teleostei. These types of cranial structure are termed 
respectively the " autostylic " and " hyostylic " 3 . It is now generally 
admitted that the first division passes through some of the early 
Dipnoan fishes into the Amphibia, and thus into terrestrial Verte- 
brates ; while it seems equally clear that the extreme specialization 
of the second division has resulted in the modern types of fishes — the 
vertebrates most completely adapted to an aquatic existence. 

Again, it will be observed that in the earliest known Palaeozoic fish- 
fauna there are representatives both of the autostylic and hyost3 ? lic 
types on the same primitive biological level, so far as the develop- 
ment of the appendicular skeleton and the axial skeleton of the trunk 
are concerned, but yet differing in the nature of the exoskeleton. 
Some families exhibit mere ' k placoid " dermal calcifications, traversed 
by delicate branching nutritive canals, these isolated plates not 
uniting even in the region of the branchial apparatus to form any 
covering of the clefts ; other families are well encased in dermal and 

J H. Stannius, « Handbuch der Zootomie— Fische,' (1846), pp. 18, 32. 

2 T. H. Huxley, ' Elements of Comparative Anatomy' (1864), pp. 195, 209. 

3 T. H. Huxley, Proc. Zool. Soe. 1876, pp. 40, 41. 



X INTRODUCTION. 

membrane-bones, which, have a definite symmetrical arrangement, 
and consist, at least in their basal layer, of tissue with distinct 
lacuna?, these being often arranged in haversian systems. All 
pahvontological evidence combines to indicate that both among the 
hyostylic and the autostylic fishes these two types of exoskeleton 
have characterized divergent or parallel phyla, exhibiting no con- 
nection since their origin ; and, if the evolution of the paired fins 
be regarded as a criterion, three of these four types (i. e., all except 
the bony hyostylic group) attained their maximum specialization 
before the end of the Palaeozoic Epoch. 

The evolution of the fins, indeed, and especially of the paired 
fins, is shown by Cope to be the most satisfactory and philosophical 
clue to the arrangement of all the minor groups of fishes. Just as 
the various modifications of the pentadactyl limb in the Ungulate 
Mammals — the vertebrates which eventually become most com- 
pletely adapted for progression on land — afford the principal means 
of determining the natural subdivision of that order ; so among the 
greater groups of fishes — the vertebrates that become specially 
adapted for progression in water — the successive modifications of 
the primitive fin-folds form the most obvious clue to the phases 
through which the various types have passed in the course of their 
specialization. 

If, in accordance with the present teaching of embryological re- 
search, the paired limbs have developed from lateral folds, the 
primitive condition of these appendages still remains undiscovered, 
and their evolution can only be traced from a comparatively ad- 
vanced stage. All the most generalized early Palaeozoic fishes 
hitherto met with exhibit two pairs of limbs, of the paddle-like 
form termed " archipterygium " by Gegenbaur : and subsequent 
specialization has resulted in the gradual atrophy of these limbs, 
usually with a concomitant development of the fringing dermal 
rays (actinotrichia). Of the median azygous fin-fold almost the 
earliest stages are known, and in this case again specialization re- 
sults, first in the subdivision and partial loss of the originally con- 
tinuous fold, then in the development of the dermal rays and the 
gradual atrophy of the endoskeletal supports, and finally in the 
intimate correlation of these two series of elements. In the most 
primitive types, there is at least a double series of endoskeletal rods 
supporting the continuous fin, directly apposed to the neural and 
haemal spines of the axial skeleton ; in later types the appendicular 
elements gradually lose all connection with the segments of the 



INTRODUCTION. XI 

endoskeleton, and are correlated instead with the merely dermal 
developments in the fin-fold itself. Though not absolutely diagnostic, 
on account of intermediate conditions, the three principal stages in 
the development of the paired fins correspond closely to three 
ordinal groups ; while the modifications of the median fins are of 
less value, sometimes not even diagnostic of divisions which other 
characters lead to be regarded as suborders. 

Summarizing the present state of knowledge, the subclasses and 
orders of fishes of which the endoskeleton has been discovered may 
thus be arranged as in the table on page xii. Another sub- 
class, that of Ostracodermi, also demands consideration in connection 
with Palaeozoic Fishes, whether or not jaws and a paired appendi- 
cular skeleton eventually prove to be absent. All these divisions 
are defined in the Catalogue itself, and it thus sufiices, by way of 
introduction, merely to justify some of the features in the arrange- 
ment adopted, and to particularly emphasize a few of the more 
important results. 

ELASMOBRANCHII. 

In the Introduction to the first part of the present Catalogue, 
published nearly two years ago, the chief known features in the 
palaeontology of the typical Elasmobranch fishes were summarized 
and discussed ; and subsequent contributions to the subject have 
been made by Doderlein 1 , Koken 2 , Fritsch 3 , and Newberry 4 . The 
researches detailed in the following pages make still further addi- 
tions to existing knowledge of the subclass ; and it now seems 
possible to recognize a feature of considerable interest that has 
hitherto escaped adequate notice. This relates to the early speciali- 
zation of the Elasmobranchii, and the extinction of all but the more 
generalized types before the end of the Palaeozoic Epoch. 

Such, at least, appears to be the most philosophical interpretation 
of the characters presented by the remarkable Palaeozoic order of 
Acanthodii. Since the first detailed description of the typical genus, 
AcantJwdes, by Roemer 5 , it has been generally admitted that this 
order of fishes is closely connected with the Elasmobranchii by 
several important characters, and some authors (e. g. Liitken 6 and 

1 L. Doderlein, Zool. Anzeiger, vol. xii. (1889), pp. 123-127. 

2 E. Koken, Sitzungsb. G-es. naturf. Freunde Berlin, 1889, pp. 77-94. 

3 A. Fritsch, ' Fauna der Graskohle,' vol. ii. pt. iv., vol. iii. pt. i. (1889-90). 

4 J. S. Newberry, ' Palaeozoic Fishes N. America ' (1889). 

5 F. Eoeraer, Zeitsclir. deutscb. geol. Ges. vol. ix. (1857), pp. 65-83, pi. iii. 

6 C. Liitken, Palaeontogr. vol xxii. (1873), p. 41. 



Xll 



INTRODUCTION. 



^ 



CD 

OQ 

< 
o 
P 



3 



00 

1 

<n 
O 

<{ 


IV. 
DIPNOI. 


SiRENOIDEI. 

[Unknown.] 
Artiirodira. 


III. 
HOLOCEPHALI. 


[Unknown.] 
Chijleroidei. 

[Unknown.] 


QB 

2 

In 

% 

O 
>> 

H 


II. 
TELEOSTOMI. 


Crossopterygii. 
(Palseoz. and Mesoz.) 

Crossopterygii. 
(Cainozoic.) 

ACTINOPTERYGII. 


i-5 
i— i 

W 

o 

m pq 
O 

CQ 

<1 


iciitiiyotomi. 
Selaciiii. 

acantiiodii. 


Stages in 
Evolution of 
Paired Fins. 


1. Archipterygium 
(elongate or abbre- 
viate). 

2. Pectorals di- or tri- 
basal ; pelvics abbre- 
viate. 

3. Basal cartilages 
small or rudimen- 
tary. 





d 

o 


s 


s 


o 




A 


^ZJ 


£ 


rt 


M 


i) 


O 


o 


> 


Oh 


o 


OQ 


C1> 


O 


^ 


H 


■+J 


o 




s- 




4-> 


o 


M 




© 






Pi 






o 


o 


^ 


o 


+a 


o 




c^ 


a 




.i-< 


§ 


3 


„ 


Od 






O 


t^ 


fl 


O 


g-ri=l 






P 






-d 


T3" 


o 


g 


rd 


a 


is 


'r-G 


pj 


ad 




r^ 


^ 


CD 




c, 


£ 


O 


~! 


w 


a 

O 






C5 


O 


-(-J 


Pj 






F« 


ad 


O 


U 


V 


-C! 




a 


m 


od 


OJ 




bn 






n 


03 

a 

o 


73 

3 


H 


o 


od 


rG 



a .a 



CD Co 

q 

•+J h. 

© Ch 

o % 

^ "2 

o ° 

,4 hi 

-P © 

3 B 



INTRODUCTION. Xlll 

Fritsch *) venture to place it in that subclass without much hesi- 
tation. Others (e. g. Huxley 2 and Traquair 3 ), however, prefer to 
retain the arrangement originally suggested by Agassiz ; and the 
current opinion seems to be that it is an annectent type between 
the Elasmobranchs and the so-called Ganoids 4 . 

The Elasmob ranch characters of the Acanthodians were well 
summarized by Huxley {op. cit.) no less than thirty years ago, and 
all the statements still remain valid. The structure of the exo- 
skeleton, the nature of the fin-spines, the absence of cranial bones, 
the absence of membrane-bones connecting the pectoral arch with 
the cranium, the exposed and well-separated condition of the gill- 
clefts, and the course of the " lateral line " between the scales on 
the trunk — all still remain typically Elasmobranch characters. It 
may also be added that another point of resemblance between the 
Acanthodians and ordinary Elasmobranchs is observable in the tail. 
In the heterocercal tail of a Teleostomous fish, when the upper 
lobe of the caudal fin disappears, it is invariably replaced by a 
series of ridge-scales ; in the Elasmobranchs, on the other hand, 
though the disappearance of the . upper caudal fin-lobe is frequent, 
it is always absolute, and leaves no trace of the former presence of 
the appendage in a modification of the squamation. The latter is 
the case among the Acanthodians, of which none but completely 
heterocercal types are known. 

The so-called " Ganoid characters " of the Acanthodians were also 
enumerated by Huxley when discussing this group ; but, unlike the 
previous series of statements, they have proved for the most part 
untenable. As pointed out by Pander 5 and Traquair 6 , the resem- 
blances between Cheirolepis and Acanthodians are merely superficial. 
The ring of circumorbital plates, suggesting a comparison with 
Palceoniscus, has lately been discovered by Newberry 7 in a Palaeozoic 



1 A. Fritsch, ' Fauna der Gaskohle,' vol. ii. (1889), p. 96. 

2 T. H. Huxley, Mem. Geol. Surv. dec. x. (1861), p. 38. 

3 R. H. Traquair, Trans. Eoy. Soc. Edinb. vol. xxx. (1881), p. 18; also Geol. 
Mag. [3] vol. v. (1888), p. 511. A query is appended to the arrangement in 
Proc. Roy. Soc. Edinb. vol. xvii. (1890), p. 387. 

4 K A. von Zittel, ' Handbuch der Palseontologie,' vol. iii. (1887), p. 165. 

5 C. H. Pander, ' Ueber die Saurodipterinen, Dendrodonten, Glyptolepiden, 
und Cheirolepiden des devonischen Systems ' (1860), pp. 69-73, with plates. 

6 R. H. Traquair, Ann. Mag. Nat. Hist. [4] vol. xv. (1875), p. 240, pi. xvii. 

7 J. S. Newberry, Mon. U.S. Geol. Surv. no. xvi. (1889), p. 104 (" eye- 
capsules "), pi. xliv. fig. 3 {Cladodus kepleri). 



XIV INTRODUCTION. 

fish which all will agree is a typical Elasmobranch. The " production 
of the pectoral arch into long baekwardly directed processes in Dipla- 
canthus" leading to a comparison with the Siluroids, is due merely 
to a pair of spinous fin-rays, which have no known analogues either 
among Elasmobranchs or Teleostomes. The " great spines articu- 
lated with the pectoral arch " cannot be regarded as of much signi- 
ficance. The so-called " oral tentacles " are endoskeletal structures, 
and probably represent the ceratohyal bones with their appended 
rays. Finally, the contention that the Acanthodii may be a degene- 
rate branch of the " ganoids " that has followed and even descended 
beneath the Chondrostean Polyodontidas, seems as destitute of 
philosophical basis as the contrary supposition that they form an 
Elasmobranch type on the verge of entering the Teleostomi. 

According to all reliable observations, when a bony squamation 
degenerates, it is never accompanied by a simultaneous develop- 
ment of the insignificant surface-layer of cosmine and vascular 
dentine, but becomes replaced by a calcified tissue of thin lamellae. 
It is thus contrary to widely-established principles to suppose that 
the order under consideration has developed from fishes with an 
osseous exoskeleton. On the other hand, the most typical of the 
early Teleostomi have archipterygial paired limbs, and hence cannot 
have been derived from the Acanthodii, which possess extremely 
specialized and abbreviated paired fins. The only alternative theory 
by which any connection whatever can be admitted between the 
two groups, seems to be the ordinary resource of a modern taxono- 
mist in difficulties — the polyphyletic origin of the higher type. 

Ear from resorting to this solution of the problem, we prefer to 
interpret the anatomical characters of the Acanthodian fishes as 
proving that they occupy the same position in the Elasmobranch 
phylum that is held at the present day by the Actinopterygians in 
that of Teleostomi. Their abbreviate fins, degenerate dentition, and 
the partial development of membrane-calcifications 1 9 indicate their 
comparatively advanced status in whatever subclass they may be 
placed ; and in the present condition of knowledge, it seems best to 
regard them as the culminating series of the Elasmobranchii at the 
time when this subclass was one of the dominant types. 

The irregular manner in which membrane-calcifications (equiva- 
lent to membrane-bones, even if not osseous) are apparently deve- 

1 No bone-lacunae have hitherto been detected in this tissue. The present 
writer has examined the mandibular splints cf Ischnacanthus and Acanthodopsis. 



INTRODUCTION. XV 

loped among the Acanthodii is, indeed, a singular and interesting 
feature. So far as the observations recorded in the following pages 
have extended, such elements only occur in the head when tho 
dentition is still preserved. In the lower jaw there is a bone pro- 
bably corresponding to the splenial ; and in the upper jaw there is 
an ensheathing element in connection with each half of the pterygo- 
quadrate arcade. In the pectoral arch, again, membrane- calcifica- 
tions have only been noticed when there are great dermal spines to 
be supported. Two elements, occupying the position of clavicle and 
infraclavicle, are especially conspicuous in the formidably armed 
Diplacanthus (see p. 23) ; Avhile in the comparatively feeble types 
of Acanthodidae and Ischnacanthidaa, such calcifications are either 
insignificant or absent. Under any circumstances the development 
of membrane-elements in the Acanthodii cannot be regarded as 
more than a family character ; and it is a striking illustration of 
the now generally received principle, that features which become of 
wide taxonomic importance in the higher groups are sporadic and 
of small significance on their first appearance in the lower groups. 

Lastly, it may be remarked that, notwithstanding the extreme 
specialization of the paired limbs, the lower Acanthodians are the 
only vertebrates in which there are any structures in the adult, 
apart from the two pairs of fins, which may be plausibly interpreted 
as remnants of once-continuous lateral folds 1 . As observed by 
Prof. Cope 2 , the earliest known members of the order (e. g. Cli- 
matius) exhibit between the pectoral and pelvic fins a close and 
regular series of paired spines, in every respect identical with those 
supporting the appendages .that presumably correspond to the two 
pairs of fins in the higher genera. They may even have supported 
fin-membranes, though specimens sufficiently well preserved to 
determine the point have not yet been discovered. However, it is 
evident that dermal calcifications attained a greater development in 
the Acanthodii than in any of the more typical Elasmobranchs : and 
much additional information on the subject may be expected when 
the great fishes to which some of the undetermined Ichthyodorulites 
pertained become known. 

1 We do not overlook the theory of the rudimentary third pair of limbs in 
Callorhynchus (T. J. Parker, ' Nature,' vol. xxxiy. 1886, p. 635). 

2 E. D. Cope, Amer. Nat. vol. xxiv. (1890), p. 407. 



XVI INTRODUCTION. 

HOLOCEPHALI. 

Of the evolution of the Chimaeroids — the only known order of 
this subclass — palaeontology at present reveals very few particulars. 
In the Lower Devonian rocks there are dental plates essentially 
similar in character to those of the still- existing Chiniaeridae ; and 
in the earliest known Chimaeroid skeleton — that of Squaloraja from 
the Lower Lias — the paired fins also differ in no particular from 
those of its surviving congeners. The Squaloraiidae and Myria- 
canthidae, however, exhibit some features in their dentition which 
may be regarded as comparatively primitive ; and in other respects 
both these early families display a few characters resulting from 
specialization, such as have not been attained in the more per- 
sistent and later types. 

As originally pointed out by Egerton x , the dentition of the 
Hyriacanthidse (and we may add also that of the Squaloraiidae) 
presents considerable superficial resemblance to that of certain 
Cochliodont Elasmobranchs ; and it is thus easy to conceive how it 
may have been developed, in a similar manner, from a dental arma- 
ture such as was possessed by the earliest members of the last- 
named subclass. In every respect the evolution has advanced 
further than in the Cochliodonts, all anterior prehensile teeth 
having disappeared ; and the growth of the dental plates, instead 
of taking place exclusively at the inner border, seems to have 
gradually extended to the whole of the attached surface. The 
Chimaeridae exhibit an advance beyond the two families just con- 
sidered, in the circumstance that all the dental plates are thickened, 
while the hinder upper pair are both closely apposed in the median 
line and much extended backwards. 

The characters in which Squaloraja and Myriacanthus exhibit a 
higher degree of specialization than the later Chimaeroids are the 
extreme development of the vertebral rings in the former and the 
presence of extensive dermal plates in the latter. 

OSTKACODEKMI. 

At the conclusion of the sections on Elasmobranchii and Holo- 
cephali, the numerous undetermined fragments of dermal armour, 
chiefly consisting of vascular dentine, and hence probably referable 
to one or other of the subclasses just discussed, are provisionally 
arranged as Ichthyodorulites. A large number of these are still 
1 Sir P. Egerton, Quart. Journ. Geol. Soc. vol. xxviii. (1872), p. 234. 



INTRODUCTION. XV11 

problematical ; and it has thus been deemed convenient to treat 
next in order the great extinct group of Chordate animals to which 
Prof. Cope l has applied the name of Ostracodermi. These pertain 
either to the Class Pisces or to some lower denomination yet to be 
determined. 

Though placed in immediate association with the TJrochorda and 
Agnatha by Cope, and lately supposed to be allies of the Arachnids 
by Patten 2 , few facts can be advanced in favour of either of these 
theoretical interpretations of the group. The Arachnid theory is 
based upon a complete misapprehension of the most fundamental 
points in Ostracoderm skeletal anatomy 3 ; while the comparison of 
the dorsal opening in the cranial shield of the Asterolepidae with 
the mouth of an Ascidian, as originally made by Cope 4 , is already 
admitted by that author himself 5 to prove untenable. That there 
were no hard parts round the mouth and in relation to paired 
appendages capable of being preserved under the ordinary condi- 
tions of fossilization seems to be satisfactorily demonstrated ; but 
there is no justification for any further statement that jaws, pectoral 
and pelvic arches were absent. On the other hand, a symmetrical 
paired series of lateral indentations on the visceral aspect of certain 
Ostracoderm dorsal shields (e. g., Cyatliaspis 6 ) suggests the original 
presence of well-separated gill-pouches, between which it is reason- 
able to infer there were supporting elements of the nature of visceral 
arches. There is a distinctly movable flap or plate at the posterior 
opening of what appears to have been a common gill-cavity outside 
these pouches in some genera (e. g., Cephalaspis and Ptericlitliys). 
In every instance when the plate between the orbital apertures can 
be distinctly observed there is a small deep pit on its visceral 
aspect, sometimes projecting as a tubercle externally ; and this 
occupies the precise position that would have been held by the 
pineal body of a vertebrate brain, had such been present. A pair 
of > -shaped impressions on the visceral aspect of the dorsal shield 



1 E. D. Cope, Amer. Nat. vol. xxiii. (1889), p. 852. 

2 W. Patten, Quart. Journ. Micro. Science, vol. xxxi. (1890), pp. 359-365, 
fig. 13. 

3 A. S. Woodward, Ann. Mag. Nat, Hist. [6] vol. vi. (1890), pp. 314-316. 

4 E. D. Cope, Amer. Nat. vol. xix. (1885), p. 290. 

5 E. D. Cope, ibid. vol. xxii. (1888), p. 915. 

6 See especially the figures by Kunth, Zeitschr. deutsch. geol. Ges. vol. xxiv. 
(1872), pi. i . fig. 1 ; A. von Alth, Abh. k. k. geol. Reichsanst. vol. vii. no. 1 
(1874), pi. v. fig. 1 ; and Lankester, ' Cephalaspidee ' (1868), pi. ii. fig. 11. 

PAKT II. b 



XV111 INTRODUCTION. 

occurring further backwards, and especially distinct in Cyathaspis l , 
are exactly such as might result from contact with ridges upon the 
auditor}' capsules, due to a great development of the upper semi- 
circular canals, as in Sharks. In short, all positive characters 
are rather in favour of an alliance with the class Pisces than 
otherwise ; and although these organisms cannot be defined with 
scientific precision, it seems advisable at present to regard them 
as a primitive Piscine subclass of uncertain affinities. 

The name Ostracodermi is preferred for this subclass, because 
Prof. Cope seems to be the only naturalist who has hitherto ven- 
tured to remove the Coccostean fishes far from the order that com- 
prises the Asterolepidae. So long ago as 1848, M'Coy 2 proposed to 
institute the " family Placodermi " for the Asterolepidae and Cocco- 
steidae, allowing Ceplialaspis to remain as the type of a distinct 
family ; and all subsequent authors seem to have adopted this 
arrangement, with only slight changes in the rank allowed to the 
great divisions. Even so recently as 1888, Traquair 3 regarded the 
Asterolepidae and Coccosteidae as separated by characters merely of 
family value; and in the latest work of Newberry 4 , the same 
classification, though not systematically formulated, is implied. It 
must, however, be remarked that both Newberry, Traquair, and 
other authors have on several occasions pointed out the close 
resemblance between the dentition of the Coccosteidae and that of 
the Dipnoi ; and it is by extending this suggestion to its logical 
issue, in the light of the latest researches, that the classification 
adopted in the following Catalogue has been attained. The Cocco- 
steidae and their allies possess ossified jaws and a dentition that are 
far from incipient or rudimentary. Some are believed to have had 
pectoral fin-spines (e. g., Dinichihys and Brachydirus) — a circum- 
stance implying the presence of highly specialized paired fins ; and 
even where pectorals have not been observed (e. g., Coccosteus), 
membrane-bones identical with those of an ordinary pectoral arch 
are certainly well developed. Coccosteus, moreover, is now proved 
to exhibit highly specialized pelvic fins. These characters suffice, 
at least in the present state of knowledge, to separate the Coccosteus- 
like fishes very widely from those now termed Ostracodermi ; and 
it may be added that even detached fragmentary plates can in many 

1 See Kunth, von Alth, and Lankester's figures already quoted. 

2 F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. ii. (1848), p. 6. 

3 K. F. Traquair, Geol. Mag. [3] vol. v. (1888), pp. 508, 511. 

4 J, S. Newberry, ' Palaeozoic Fishes N. America' (1889). 



INTRODUCTION. XIX 

cases be readily distinguished. All the dermal armour of the 
Ostracoderms is characterized by an extraordinary development of 
vascular sinuses or channels in the middle layer, while that of 
Coccosteus and its allies consists of nearly homogeneous dense bone 
with only a slightly cancellated structure in its thicker portions. 

The marked affinity between the Heterostraci and Osteostraci has 
already been demonstrated by Huxley x and Lankester 2 ; and all 
the recent observations detailed in the following Catalogue tend to 
confirm the general results of that demonstration. It is, however, 
necessary to add a few remarks on the relationship now perceived 
between the Antiarcha (i. e., the family Asterolepidse) and the 
Osteostraci; more especially as these have not hitherto been 
enumerated, and Cope's statement on the subject is made with 
hesitation. The comparatively specialized genera Auchenaspis, 
Didymaspis, and Tremataspis may first be compared with 
Pterichthys in the arrangement of the dermal armour. In each case 
the head exhibits only a dorsal shield, while the abdominal region 
is covered both dorsally and ventrally by an armature that meets in 
a close suture laterally. As clearly shown in Tremataspis, and less 
distinctly observed in the other Osteostraci just mentioned, the 
ventral shield terminates abruptly in front, as in Pterichthys ; and 
the only fundamental difference between the specialized Osteo- 
stracan and the ordinary Antiarchan type seems to be that the 
armature of the former consists of few p]ates, while these are sub- 
divided in the latter. In the Antiarcha, again, the interorbital or 
pineal plate is always loose so far as known, while it is fixed in all 
Osteostraci except Tremataspis ; but even when fixed the outline 
can be readily distinguished in some examples of Cephalaspidse, and 
there is a fine fragment of Eakeraspis displaying the contour of 
this element in the Ludlow Museum. Ln the absence of narial 
openings in the cranial shield, both types also agree ; and the 
olfactory organ, if present, must thus have retained its embryonic 
situation on the ventral aspect immediately in front of the mouth. 
In short, so far as the shield can afford a clue to the essential soft 
parts, these were arranged upon one and the same plan in Hetero- 
traci, Osteostraci, and Antiarcha. 

Finally, the caudal region, as known in Cephalaspis, may be 
compared with that of Pterichthys in all essential particulars ; and 

1 T. H. Huxley, Quart. Journ. Geol. Soc. vol. xiv. (1858), pp. 267-280, 
pis. xiv., xv. 
a E. E. Lankester, 'The Cephalaspidae ' (Mon. Palaeout. Soc. 1867-69). 



XX INTRODUCTION. 

although there are no paired appendages in the former genus, we 
are inclined to think that another noteworthy point of resemblance 
occurs in the appendicular skeleton, the rows of plates in the 
paddles of the Asterolepidas being an extreme modification of the 
arrangement observed in the azygous fin-membranes of the Cepha- 
laspidoe, and markedly different from the actinotrichian development 
by which the fin-rays of ordinary fishes arise. Even the support of 
the anterior border of the dorsal fin oiPterichthys is not a true spine, 
but merely a longitudinally bent (perhaps primitively double) scale. 



DIPKOI. 

Concerning the evolution of the Dipnoi, palaeontology as yet 
affords no information. So long ago as the Devonian period, there 
were members of the subclass agreeing precisely with the existing 
Ceratodus in the development of the fins and the axial skeleton of 
the trunk. At that remote period, too, the chief part of the 
dentition had assumed the form of great plates upon the splenial 
bones and the palate ; and the principal difference between such a 
type as Phaneropleuron and the existing genus just mentioned 
seems to consist in the comparative fewness of the cranial roof- 
bones in the latter and the absence of membrane-bones on the 
margin of the jaw. The typical Dipnoi of the Devonian period had, 
indeed, already become more specialized than any known in later 
times ; Dipierus exhibiting differentiated dorsal fins and a hetero- 
cercal tail. 

The latter fact is of all the more interest when the tendency of 
modern research in regard to the Coecosteus-]ike fishes is taken 
into consideration. According to existing diagnoses, these fishes 
must be assigned either to the Dipnoi or to the Teleostomi ; and 
the extremely specialized character of their paired fins, so far as 
known, proves that, wherever they be placed, they occupy a com- 
paratively high position. If they are Teleostomi, they pertain to 
the Actinopterygian order, and hence ought to exhibit a well- 
developed hyomandibular bone. At least, in every undoubted 
Actinopterygian Teleostome possessing ossifications equal in extent 
to those of Coccostens and its allies, the hyomandibular bone is both 
large and considerably ossified. In the extinct group now under 
discussion, however, such a bone is not exhibited even by the most 
exquisitely preserved specimens. On the other hand, all appear- 
ances in the crania of Dinichihys and allied genera from the Waverlv 



INTRODUCTION. XXI 

Group of the United States are in favour of the supposition that 
they are truly autostylic. As originally pointed out by Newberry x , 
the dentition of Dinichthys is most nearly paralleled by the existing 
Dipnoan Protqpterus. The recently discovered triturating plates of 
Mylostoma would have been assigned to the Dipnoi or Chimaeroidei, 
if they had not fitted certain associated mandibular bones identical 
in shape with those of the Dinichthys-tyipe : on one page, indeed, 
Newberry terms the fish a " Placoderm " 2 , while on another it is a 
" Dipterine Ganoid " 3 . The bones of the cranial shield, while 
apparently homologous throughout the group, cannot be described 
by the terms that are applicable to all Teleostomi, except perhaps 
the modern Acipenseroids ; but these bones are symmetrically 
disposed with respect to the median longitudinal line, and are thus 
worthy of a nomenclature. In short, the evidence in favour of the 
autostylic character of the Coccostean fishes has now accumulated 
to such an extent, that we venture to regard them as an order of 
Dipnoi, bearing the same relation to the Sirenoidei that the Acan- 
thodians seem to hold with respect to the primitive Elasmobranchs 
(Tchthyotomi), or the Actinopterygians with respect to the primitive 
Teleostomes (Crossopterygii). For this order the name Arthrodira 
is suggested, in allusion to the ginglymoid articulation by which the 
cranial shield is hinged upon the anterior border of the armour of 
the abdominal region in the typical and best known genera. 



TELEOSTOMI. 

It is generally admitted that the Crossopterygian Teleostomi are 
closely related to the Dipnoi, and the Devonian representatives of 
this order tend in some degree to lessen the hiatus between the 
two great subclasses. Since, however, all the early Crossopterygii 
hitherto discovered conform to the normal Teleostome type in the 
arrangement of the bones of the cranial shield, it seems probable 
that the two groups had already diverged before the development 
of membrane-bones commenced. 

The most interesting feature of the Crossopterygii consists in the 
mode of specialization of their fins ; and this, as pointed out by 
Cope, affords a satisfactory basis for the definition of the suborders. 
In all the known Palaeozoic and Mesozoic members of the order the 

1 J. S. Newberry, Eep. Geol. Surv. Ohio, vol. ii. pt. ii. (1875), p. 6. 

2 J. S. Newberry, ' Pakeoz. Fishes N. America ' (1889), p. 122. 

3 Ibid. p. 161. 



XX11 INTRODUCTION. 

paired fins are truly archipterygial, whether elongate or abbreviate ; 
while in the existing Polypteridae the pectoral fins have lost all 
trace of the original branched arrangement of the cartilages (pre- 
cisely like the Sharks), and in Polypterus itself the pelvic fins are 
approximately in the same condition as those of one of the Actino- 
pterygian Chondrostei. Among the early families, the characters 
of the median fins lead to the recognition of two or three divisions. 
It is probable that one type in which the median fin remains 
undivided and more or less in its primitive condition will eventually 
be met with, even if it be not already known. This group has 
received the name of Haplistia, and we provisionally assign to it 
the problematical Tarrasiidae. The second and third types, though 
now clearly definable, are not satisfactorily formulated in the some- 
what fluctuating classifications of Cope ; and the terms Rhipidistia 
and Actinistia are selected on the present occasion from those 
already proposed by that author, as being most expressive and 
accurate. For their diagnosis and description, reference may be 
made to the Catalogue itself; and it only seems necessary here to 
remark upon the extraordinary manner in which the specialized 
dorsal fins of the Bhipidistia resemble paired limbs (see especially 
fig. 50, p. 335). When subdivided, the dorsal fin invariably 
degenerates to two portions, and these are supported on a plan that 
does not differ much from that of an abbreviate archipterygium. 

The great group of Actinopterygian Teleostomi is that con- 
cerning which palaeontology affords most extensive information ; 
but as only the typically Palaeozoic families of Palaeoniscidae and 
Platysomatidae are comprised in the present volume, it will be con- 
venient to defer general observations on their relationships until the 
completion of Part III. 

In conclusion, there is little to add concerning the details of the 
plan of the Catalogue to the statement already made in the Intro- 
duction to Part I. Family names derived from generic names 
terminating in -aspis and -lepis occur now for the first time ; and, 
from the point of view of euphony, it has been deemed advisable 
to omit the reduplication of " id" which would be necessitated by a 
strict adherence to classical rule. There is already justification for 
this procedure in the universal adoption of the term Crossopterygii 
instead of the strictly accurate Crossotopterygii. More descriptive 
sections have been included than in the former volume, on account 
of the importance of the Palaeozoic types to the modern Biologist, 



INTRODUCTION. XX111 

and the want of any general work on the subject comprising the 
latest discoveries. The entirely novel points in most of these 
descriptions are few ; but in every case the statements are based 
upon personal observation, unless the contrary be definitely 
remarked. Finally, an attempt is made to render the Catalogue 
more nearly complete in recording the collections where the various 
type specimens are preserved ; but it is still impossible to trace 
many of the types originally in private collections, and a large pro- 
portion of these have doubtless been lost. 

In this volume, as in the last, much is provisional, and can only 
be regarded as a tentative basis upon which to found more elaborate 
researches as additional materials and facilities for comparison accu- 
mulate. So far as practicable, however, all evidence bearing upon 
the subject has been taken into consideration ; and in addition to 
consulting the principal British Collections, the writer has had the 
privilege of visiting those of Berlin, Breslau, Munich, Prague, 
Stockholm, St. Petersburg, Moscow, New York, Philadelphia, 
Ottawa, Montreal, and Cambridge (Mass.), all of which comprise 
specimens of essential importance. To the Professors in the various 
Universities and the Curators of the Museums, thanks are respect- 
fully tendered for the facilities and kind assistance they have invari- 
ably afforded • and both to Mr. William Davies, F.G.S., and Dr. R. H. 
Traquair, F.R.S., as also to Mr. James W. Davis, F.Gr.S., and 
Mr. John "Ward, F.G.S., the writer is under the deepest obligations 
for continued help and advice. 

ARTHUR SMITH WOODWARD. 

Geological Department, 
January 20th, 1891. 

List of Collections. 

In addition to the Collections enumerated in Part I. (p. xxix), 
the following are also referred to in the present volume : — 

Bryson Collection. — A series of fossil fishes and plants, chiefly 
from the Scottish Carboniferous, collected by the late Mr. James 
Bryson, of Edinburgh, and obtained by purchase, 1868. 

Goldenherg Collection. — A small collection of fossils from the 
Lower Permian of Rhenish Prussia, made by Dr. F. Goldenherg 
(author of ' Fauna Saraepontana Fossilis,' 1873-77), purchased 1889. 

Lightbody Bequest. — A portion of the collection of the late Mr. 
Robert Lightbody, F.G.S., of Ludlow, comprising fossil fishes from 



XXIV INTRODUCTION. 

the Upper Silurian and Old Red Sandstone of Herefordshire, 
bequeathed to the Trustees, 1874. 

Peach Collection.. — A series of fossil fishes from the Lower Old 
Red Sandstone, chiefly of Caithness, collected by the late Mr. Charles 
W. Peach, A.L.S., obtained by purchase, 1870. 

Whincopp Collection. — Fossils from the Pliocene Crags of Suffolk 
and Norfolk, collected by the late Mr. W. "Whincopp, of Woodbridge, 
purchased through Mr. E. Charlesworth. 

It may be added that a few of the type specimens of Ichthyo- 
dorulites from the Carboniferous Limestone, formerly in the Collec- 
tion of the Earl of Enniskillen, were lost in transit immediately 
before the acquisition of this Collection by the Museum. These 
specimens are noted in the Catalogue as " olim Enniskillen Col- 
lection." 

Supplement. 

On account of the rapid progress of researches in Fossil Ichthyo- 
logy at the present time, it seems advisable to defer the issue of any 
Supplement to this Catalogue until its completion. In regard 
to Part I., we would thus only add that a recent discovery (Proc. 
Zool. Soc. 1889, p. 450) suggests that the so-called Squatina 
crassidens is the trunk of SclerorJiynchus atavus ; while an important 
Permian genus and species, Diclielodus acutus (C. Giebel, Zeitschr. 
gesammte Naturw. vol. ix. 1857, p. 121, pi. iv.), is unfortunately 
overlooked, both in this Catalogue and apparently in all the 
synoptical accounts of the Cochliodontidaa hitherto published. 



SYSTEMATIC INDEX 



OP 



GENERA AND SPECIES 

DESCRIBED IN PART II. 



Page 

Subclass ELASMOBRANCHII (continued) 1 

Order ACANTHODII 1 

Family ACANTHODIDJE 2 

Acanthodes 2 

bronni 5 

rouvillei 7 

wardi 8 

nitidus 9 

pygmasus 10 

concinnus 10 

pusillus 11 

peachi 12 

mitchelli 13 

affinis 14 

Acanthodopsis 15 

wardi 15 

Cheiracanthus 16 

murchisoni 16 

latus 19 

grandispinus 20 

PATtT II. c 



XXVI SYSTEMATIC INDEX. 



A Pa e e 

Family ISCHNACANTHIDJE 20 

Ischnacanthus 20 

gracilis 21 



Family DIPLACANTHID^E 22 

Diplacanthus 23 

striatus 24 

longispinus 26 

Climatius 28 

reticulatus 28 

scutiger 29 

uncinatus 30 

macnicoli 30 

grandis 31 

gracilis 32 

(?)ornatus 32 

(?) latispinosus 33 

Parexus 33 

incurvus 34 

falcatus 34 



Subclass H0L0CEPHALI . 36 

Order CHIM^EROIDEI 36 

Family PTYCTODONTID^E 37 

Ptyctodus 38 

Rhynchodus 39 

Palaeomylus . . , 39 

Family SQUALORAIID JE 40 

Squaloraja 40 

polyspondyla 41 

tenuispina 43 

Chalcodus 43 



~\ 



SYSTEMATIC INDEX. XXVll 

Page 
Family MYEIACANTHID^E 43 

Myriacanthus 43 

paradoxus 44 

granulatus 49 

Chimaeropsis 51 

paradoxa 52 



Family CHBLEBIDuE 52 

Ganodus 55 

oweni 55 

dentatus 57 

rugulosus 57 

sp 58 

Ischyodus 59 

colei 60 

emarginatus 60 

egertoni 61 

dufrenoyi 62 

beaumonti . 63 

townsendi 64 

quenstedti 66 

avitus 66 

planus 67 

thurmanni 67 

latus 70 

(?) incisus 70 

Edaphodon 73 

sedgwicki 73 

mantelli 75 

agassizi 77 

crassus 78 

reedi 79 

bucklandi 80 

leptognathus 81 

(?)laminosus 83 

Callorhynchus 87 

c2 



XXY1U SYSTEMATIC INDEX. 

Family CHIM^ERID^E (continued). 



Page 

Callorhynchus hectori 87 

Elasmodectes 88 

willetti 88 

Elasmodus 88 

hunteri 89 

greenoughi 90 

Chimaera 91 

pliocenica 91 



ICHTHYODORULITES 92 

Onchus 94 

murchisoni 94 

tenuistriatus 95 

quadrisulcatus 96 

• (?)granulatus 96 

(?) major 96 

Ctenacanthus 97 

major 98 

denticulatus 100 

brevis 100 

heterogyrus 101 

sulcatus 101 

(?) lsevis 102 

(?) pustulatus 102 

Homacanthus 105 

arcuatus 105 

microdus 105 

Acondylaeanthus 107 

attenuatus 107 

colei 108 

tenuistriatus 108 

distans 108 

Asteroptychius 110 

ornatus 110 

Cosmacanthus Ill 

marginalia 112 



SYSTEMATIC INDLX. XXIX 

ICHTHYODORULITES {continued). 

Page 

Cosmacanthus carinatus 112 

priscus 112 

Lispacanthus 113 

retrogradus 114 

Lepracanthus ■. ... 114 

colei 114 

Nemacanthus 115 

monilifer 116 

brevis Il7 

Gnathacanthus 118 

triangularis 118 

striatus 118 

Apateacanthus 118 

vetustus 119 

Pristacanthus 119 

securis 119 

Coelorhynchus 120 

rectus 120 

gigas 122 

cretaceus 122 

MachaBracanthus 123 

sulcatus 123 

Haplacanthus 124 

marginalis . 124 

Heteracanthus 125 

politus 125 

heterogyrus 125 

Psammosteus 126 

maeandrinus 126 

■ arenatus 127 

paradoxus 128 

Stethacanthus 129 

Physonemus 130 

— — arcuatus 130 

attenuatus 130 

hamatus 131 



XXX SYSTEMATIC INDEX. 

ICHTHYODORULITES (continued). 

Page 

Stichacanthus 133 

coemansi 133 

tortworthensis ....... 134 

Oracanthus 135 

milleri 135 

pustulosus 138 

pnigeus 138 

Gyracanthus 139 

formosus 140 

Aganacanthus 145 

Erismacanthus 146 

jonesi 146 

major 147 

Listracanthus 148 

Byssacanthus 149 

crenulatus 149 

Edestus 151 

heinrichsi 152 

minor 153 

davisi 153 

Cynopodius 154 

crenulatus 154 

Euctenius 155 

unilateralis 155 

Family CCELOLEPHLE 157 

Ccelolepis 158 

Thelodus 158 

parvidens 158 



Subclass OSTRACODERMI 159 

Order HETEROSTRACI 159 

Family PTERASPHLE 159 

Pteraspis 160 



SYSTEMATIC INDEX. 



XXXI 



Family PTERASPID^E (continued) 

Pteraspis rostrata 

crouchi . 

Palaeaspis . . 

sericea . 

americana 

Cyathaspis 

banksi . 

macculloughi 



Page 
162 

167 

169 

169 

170 

170 

170 

172 



Order OSTEOSTRACI 176 

Family CEPHALASPID^E 176 

Cephalaspis 177 

lyelli 179 

salweyi 181 

powriei 182 

pagei 183 

murchisoni 185 

lightbodii 190 

campbelltonensis 190 

dawsoni 192 

laticeps 192 

Eukeraspis 193 

pustulifera ........ 193 

Auchenaspis 195 

salteri 196 

egertoni 196 

verrucosa 198 

Didymaspis 199 

grindrodi 199 

Family TREMATASPID^E 201 

Tremataspis 201 

schrenki 202 



XXX11 SYSTEMATIC INDEX. 

Page 

Order ANTIARCHA 202 

Family ASTfcROLEPIDJE 203 

Asterolepis 203 

ornata 204 

concatenata 205 

maxima 206 

Pterichthys 208 

milleri 212 

testudinarius 216 

productus 217 

oblongus 219 

— — rhenanus 222 

Mierobrachium 223 

Bothriolepis 223 

ornata 225 

panderi 225 

major 226 

obesa 228 

canadensis 228 

hydrophila 230 

macrocephala 231 

Family CERASPID^S 233 

Ceraspis 233 

carinata 233 



Subclass DIPNOI 234 

Order SIRENOIDEI 235 

Family DIPTERIILE .235 

Dipterus 235 

valenciennesi 236 

macropterus 240 

(?) 6erratus 240 

— — (?) marginalis 241 



SYSTEMATIC INDEX. XXX111 

Family DIPTEHID^E (continued). 

Page 

Dipterus (?) radiatus 241 

Palaedaphus 243 

insignis . . 243 

devoniensis 243 

lesleyi 244 

Conchodus ..... 245 

Ganorhynchus 245 

woodwardi 245 

Family PHANEROPLEURID^E 246 

Phaneropleuron 247 

andersoni 247 

curtum 248 

Uronemus 249 

lobatus 249 

splendens 250 

Family CTENODOXTHLE 250 

Ctenodus 250 

cristatus 251 

interruptus 254 

murchisoni 255 

Sagenodus 255 

inaequalis 256 

quinquecostatus 260 

Family LEPIDOSIRENIT^E 264 

Ceratodus 264 

latissimus 265 

parvus 267 

— — guentheri 268 

capensis 269 

phillipsi 269 

— kaupi 270 

runcinatus v 272 

hislopianus 273 



XX XIV BrSTEMATIC INDEX. 

Family LEPID0SIRENIM1 (continued). 

Page 

Ceratodus hunterianus 273 

Gosfordia 275 

■ truncata 275 

Conchopoma 276 

gadiforme 276 



Order A ETH ROD Hi A 276 

Family COCCOSTEIME 277 

Coccosteus 278 

decipiens 282 

minor 291 

disjectus 292 

hercynius 292 

Brachydiras 294 

— Phlyctsenaspis 295 

acadica 295 

anglica 296 

Chelyophorus 299 

Diniehthys 300 

Titanichthys 302 

Macropetalichthys 303 

Homosteus 304 

formosissimus 304 

milleri 306 

Heterosteus 308 

asmussi 308 

Family ASTEROSTEIME 312 

Asterosteus 312 

Family PHYLLOLEPHLE 313 

Phyllolepis 313 

concentrica 314 

Holonema 314 



SYSTEMATIC INDEX. XXXV 

Page 

Family MYLOSTOMATID^E 315 

Mylostoma 315 



Subclass TELEOSTOMI 316 

Order CROSSOPTERYGII 316 

Suborder HAPLISTIA 317 

Family TARRASIID.E 317 

Tarrasius 317 

problematicus 317 

Suborder RHIPIDISTIA 318 

Family HOLOPTYCHI1TLE 321 

Holoptychius 322 

nobilissimus . . • 323 

giganteus 325 

americanus 326 

halli 326 

flemingi 327 

(Glyptolepis) leptopterus .... 331 

(Glyptolepis) quebecensis .... 336 

(Glyptolepis) paucidens . ... 336 

Dendrodus 338 

biporcatus 338 

strigatus 339 



l o l 



Family RHIZODONTID^E 341 

Rbizodus 342 

bibberti 342 

ornatus 346 

Strepsodus 348 

sauroides 349 

• striatulus 352 

sulcidens 352 



XXX\i SYSTEMATIC INDEX. 

Family RHIZODONTKLE (continued). 

Page 

Strepsodus portlocki 353 

hardingi 353 

Ehizodopsis 354 

sauroides 355 

robusta 357 

Gyroptychius . 358 

microlepidotus 358 

Tristichopterus * • 360 

alatus 360 

Eusthenopteron 361 

foordi 362 

Cricodus 363 

ineurvus 363 

wenjukowi 363 

Sauripterus 364 

favosus 365 

anglicus 366 

Family OSTEOLEPID^E 367 

Osteolepis 368 

macrolepidotus 368 

microlepidotus 371 

Ttmrsius 373 

macrolepidotus 373 

pholidotus 374 

Diplopterus 375 

agassizi 375 

MegaJichthys 378 

hibberti 378 

■ coccolepis 383 

• intermedins 384 

laticeps 386 

pygmaeus 387 

Glyptopomus 389 

minus * 389 



SYSTEMATIC INDEX. XXXVU 

Family OSTEOLEPID^E (continued). 

Page 

Glyptopomus sayrei 390 

kinnairdi 390 

Family ONYCHODONTID^: 391 

Onychodus 392 

sigmoides 392 

anglicus 392 

I 

Suborder ACTINISTIA 394 

I 

Family CCELACANTHID^ 394 

Ccelacanthus 399 

granulatus 400 

tingleyensis 402 

elegans 403 

robustus 406 

elongatus 406 

huxleyi 407 

gracilis 408 

Graphiurus 409 

Diplurus 409 

Undina 409 

penicillata 410 

gulo 411 

(?) barroviensis 413 

Libys . 413 

polypterus 414 

superbus 414 

Coccoderma 415 

Heptauema . 415 

Macropoma 416 

mantelli ......... 416 

Suborder CLADISTIA 423 



XXXVUl SYSTEMATIC INDEX. 



Page 

Order ACTINOPTERYGII 423 

Suborder CHONDROSTEI 423 

Family PAI^EONISCID^ ........ 424 

Canobius 430 

ramsayi 431 

elegantulus 431 

pulchellus 432 

politus 433 

macrocephalus 433 

Gonatodus 434 

punctatus 434 

macrolepis 435 

parvidens 435 

Amblypterus 437 

latus 437 

traquairi 439 

dnvernoyi 440 

beaumonti 443 

decorus 444 

arcuatus 444 

reussi 445 

blainvillei 445 

voltzi 446 

Eurylepis 448 

tuberculata 449 

granulata 449" 

Cheirolepis 451 

trailli 452 

canadensis 457 

Nematopty chins 457 

greenocki 458 

Cycloptychius 459 

carbonarius 460 

concentricus 461 



SYSTEMATIC INDEX. XXXIX 

Family PAL^EONJSCID^E (continued). 

Page 

Rhadinichthys 461 

ornatissimus 462 

carinatus 463 

brevis 463 

elegantulus 464 

macconochii . 464 

cairnsi 465 

alberti 465 

modulus 466 

tenuicauda 466 

wardi 467 

monensis 467 

(?) angustulus 468 

(?) fusiformis ........ 468 

Pygopterus , . 470 

humboldti 470 

Trachelacanthus 475 

Urolepis 475 

Phanerosteon 476 

mirabile 476 

Palaeoniscus 476 

freieslebeni 477 

magnus 480 

macropomus 482 

longissimus 483 

macrophthalmus 483 

Apateolepis 486 

australis 486 

Elonichthys 4^7 

germari 487 

semistriatus 488 

peltigerus 489 

aitkeni 490 

striatus 491 

macropterus 491 

(?)gigas 494 



SYSTEMATIC INDEX. 

Family PALJEONISCIDJE (continued). 

Page 

Elonicbthys egertoni 494 

robisoni 495 

bucklandi 497 

pulcherrimus 498 

serratus 499 

(?)portlocki 499 

Acrolepis 501 

sedgwicki 501 

exsculpta 505 

hopkinsi 506 

wilsoni 507 

semigranulosa 507 

ortbolepis 508 

(?) hortonensis 508 

(?)digitata 509 

Gyrolepis 510 

albertii 510 

ornata 512 

quenstedti 513 

■ agassizi 513 

Atberstonia 514 

scutata 514 

Myriolepis 515 

clarkei 515 

Oxygnatbus 516 

ornatus 516 

egertoni 520 

Centrolepis 520 

aspera 521 

Crypbiolepis 522 

striata 523 

Coccolepis 523 

bucklandi 524 

andrewsi 524 

liassica 525 

anstralis 525 



diii 



LIST OF WOODCUTS. 



Page 

Fig. 1. Acanthodes wardi. Restoration 2 

2. bronni. Pectoral fin 4 

3. Diplacanthus striatus. Pectoral arch and fins . . 23 

4. Parexus falcatus. Pectoral arch and fin .... 35 

5. Ptyctodus obliquus. Tooth 38 

6. Palatine teeth of Chimasridae. Diagrams of the oral 

aspect 51 

7. Mandibular teeth of Chimaeridae. Diagrams of the 

inner aspect 54 

8. Edaphodon leptognathus. Mandibular tooth ... 82 

9. Lepracanthus colei. Dorsal fin-spine 115 

10. Gyracanthus formosus. Fin-spine 142 

11. Harpacanthus fimbriatus. Spine . . . . . . 151 

12. Edestas minor. Portion of spine 152 

13. Euctenius unilateralis. Spines 155 

14. Pteraspis rostrata. Dorsal shield 160 

15. rostrata. Restoration 161 

16. crouchi. Portion of dorsal shield .... 168 

17. Cyathaspis. Outline of dorsal shield 171 

18. Cephalaspis lyelli. Outline of dorsal shield . . . 177 

19. Cephalaspis. Inferior aspect of dorsal shield . . . 178 

20. Cephalaspis. Transverse section of dorsal shield . . 179 

21. Cephalaspis lyelli. Restoration 180 

22. powriei. Outline of dorsal shield .... 183 

23. pagei. Outline and superficial ornamentation 

of dorsal shield 184 

24. murchisoni. Restoration 185 

25. murchisoni. Outline and superficial ornamen- 
tation of dorsal shield . . J 86 

26. dawsoni. Dorsal aspect, and portion of super- 
ficial ornamentation 192 



xliv LIST OF WOODCUTS. 

Page 
Fig. 27. Eukeraspis pustulifera. Outline and superficial 

ornamentation of dorsal shield 194 

28. Auchenaspis salteri. Outlive of dorsal shield . . 196 

29. egertoni. Outline of dorsal shield .... 196 

30. Didymaspis grindrodi. Outline of dorsal shield . . 199 

31. 32. Tremataspis schrenki. Outline of dorsal and 

ventral shields 201 

33. Pterichthys testudinarius. Restoration .... 209 

34. Bothriolepis canadensis. Outline of cranial shield . 224 

35. hydrophila. Restoration 230 

36. Dentition of Extinct Dipnoi (Dip terns, Ctenodus, 

Sagenodus, and Palaedaphus) 234 

37. Dipterus valenciennesi. Cranial shield .... 237 

38. valenciennesi. Ventrcd aspect 239 

39. Phaneropleuron andersoni. Restored outline . . . 247 

40. Ceratodus forsteri. Mouth, with dentition . . . 264 

41. forsteri. Lateral aspect 265 

42. Coccostens decipiens. Outline of dorsal and cranial 

shield 279 

43. decipiens. Outline of ventral shield .... 281 

44. decipiens. Restoration 282 

45. Dinichthys terrelli and D. hertzeri. Dentition . . 300 

46. Homosteus milleri. Outline of dorsal and cranial 

shield 307 

47. Rhizodopsis sauroides. Restoration of head . . . 319 

48. Transverse section of Holoptychian (Dendrodont) 

tooth 322 

49. Holoptychius flemingi. Dorsal aspect of head . . 328 

50. (Glyptolepis) leptopterus. Base of dorsal Jin . 335 

51. Strepsodns sanroides. Tooth ........ 350 

52. Onychodus anglicus. Presymphysial bone .... 393 

53. Undina gulo. Restoration 412 

54. Palaeoniscus macropomus. Restoration of head and 

pectoral arch 425 

55. macropomus. Restoration 482 

56. Eurynotus crenatns. Restoration 530 

57. Cheirodus granulosus. Restoration 537 

58. Platysomus gibbosus. Restoration 543 



SYSTEMATIC INDEX. lli 

Family PAL^EONISCID^E (continued). 

Page 

Holurus 526 

parki 526 

Family PLATYSOMATDLE 527 

Eurynotus 528 

crenatus 529 

Mesolepis 531 

wardi 532 

scalaris 533 

Globulodus 534 

macrurus 534 

Wardichthys 535 

cyclosoma 535 

Cheirodus 535 

granulosus 536 

striatus 539 

Cheirodopsis 540 

geikiei 541 

Platy8omus 541 

gibbosus 542 

forsteri 546 

parvulus 546 

tenuistriatus 548 

rotundus 549 

superbus 549 



PART II. 



CATALOGUE 



OF 



FOSSIL FISHES 



PART II. 



Subclass I. ELASMOBRANCHII (continued). 
Order III. ACANTHODII. 

Notochord persistent ; endoskeletal cartilage superficially calcified, 
often granulated. Cranial roof covered with irregular small dermal 
elements, and orbit frequently surrounded by circumorbitaljplates ; 
teeth, when present, firmly fixed to membrane-bones upon the 
pterygoquadrate and mandibular cartilages. Gill-arches each with 
a close series of prominent dermal appendages, probably supports 
for a cutaneous flap. Endoskeletal cartilages of all the fins much 
abbreviated, and the dermal expansion almost or completely desti- 
tute of rays ; each of the paired fins and most of the median fins 
provided with an anterior spine ; no claspers in the male. Tail 
heterocercal. Dermal armature of trunk consisting of small, closely 
arranged, quadrate granules, which also extend over the greater 
portion of the fins ; lateral line passing between two series of the 
granules. 

Synopsis of Families. 

A. One dorsal fin. 

Clavicular bones absent Acanthodid^e (p. 2). 

B. Two dorsal fins. 

Clavicular bones absent Ischnacanthidje (p. 20). 

Clavicular bones present Diplacantbtd^ (p. 22). 

PART II. B 



4 ACANTHODTI. 

Family ACANTHODID^E. 

A single dorsal fin present, both this and the anal with an 
anterior spine. Clavicular bones absent. 

Synopsis of Genera. 

A. Teeth minute or absent. 

Dorsal fin not in advance of anal Acantkodes (p. 2). 

Dorsal fin in advance of anal Cheiracanthus (p. 16). 

B. Teeth large. 

[Arrangement of fins unknown.] Acanthodopsis (p. 15). 

Genus ACANTKODES, Agassiz. 

[Poiss. Foss. vol. ii. pt. i. 1833, p. 19.] 

Syn. Acanthoessus, L. Agassiz, Neues Jahrb. 1832, p. 149. 

Holacanthodes, E. Beyrich, Monatsb. Berl. Akad. 1848, p. 24. 
Mesacanthus, K. H. Traquair, Geol. Mag. [3] vol. v. 1888, p. 511. 

Body elongate, tapering, and laterally compressed. Teeth minute 
or absent ; orbit with ring of four circumorbital plates. Pectoral 
fins very large ; pelvic pair smaller. Dorsal fin remote, never 
arising in advance of a point opposite the anal fin-spine. 

, Fig. 1. 




Restoration of Acantkodes wardi, Egert. — Coal-Measures, England and 
Scotland. 

This, the type genus of the family and order, has been more 
thoroughly investigated than any of the allied genera \ It thus 
seems advisable to summarize the known facts in the anatomy of the 
fish, and compare some of its more striking features with those pre- 
sented by certain members of the Diplacanth family. 

In the head, the suspensorium is oblique and the gape of the 
mouth correspondingly wide. The orbit is placed far forwards, and 
the upper jaw evidently projects somewhat in advance of the lower. 
The cartilage of the cranium and jaws is partially strengthened by 

1 See especially the memoirs of Roetner and Kner, quoted in the synonymy 
of A. hrovni. 



ACANTlIODll)^. O 

minute granular calcifications. There is no definite evidence of 
membrane-bones bordering the mouth ; but in genera which possess 
teeth (e.g. Acanthodopsis and Ischnacanthus) the oral margin both 
of the upper and lower jaws is ensheathed in a well-developed mem- 
brane-bone. In the small species from the Old Red Sandstone the 
roof of the skull is distinctly covered with an irregular mosaic of 
small dermal scales ; and in all the species a circumorbital ring of 
four dermal plates is conspicuous. Between the rami of the lower 
jaw, there occurs a pair of slender cartilages, not expanded at the 
extremities, but firmly calcified ; and these are accompanied by a 
sparse series of delicate rays in such a manner as to suggest that 
they represent the ceratohyals l . The branchial arches, of which 
there are five, are also calcified ; and on the hinder or convex margin 
of each is arranged a close series of lanceolate appendages, having 
the free extremity broader than the attached end, and not impro- 
bably destined for the support of dermal flaps, resembling those 
upon the gill-arches of the recent " frilled shark," Chlamydoselache. 

The cast of a pair of large oval lobes has been observed in the 
head of a Siberian species 2 , these not improbably indicating the 
form and proportions of part of the cerebral cavity. 

In the axial skeleton of the trunk the notochord is persistent, 
and the arches are so rarely observable that they must have been 
very slightly calcified. There are no traces of ribs, but a series of 
slender neural arches is feebly indicated in a specimen from the 
Calciferous Sandstones of Eskdale (no. P. 5979, p. 10) ; and stout 
haemal arches are sometimes preserved in the region of the caudal 
fin in examples of the type species from the Permian nodules of 
Rhenish Prussia. 

Each of the fins, except the caudal, is provided with an anterior 
spine, which resembles that met with in the dorsal fins of many 
well-known Selachians, and is to be similarly regarded as an enor- 
mous dermal ray. The fin-membrane is always stiffened by quadrate 
dermal granules of the same nature as those covering the trunk, 
and these are often arranged in regular lines simulating rays ; but 
the pectoral and caudal are the only fins in which any traces of the 
endoskeletal elements have hitherto been observed. 

At the base of each pectoral fin-spine (fig. 2) there abuts against 
its posterior or concave border the broader end of a supporting 
cartilage (6), which is elongated in a direction at right angles to the 
spine (s), is constricted shortly above this articulation, and ends 

1 " Oral tentacles " of Huxley, and " styliforni bones forming the rami of the 
lower jaw " of Egerton. 

2 J. V. Rohon, Mem. Acad. Imp. Sci. St. Petersbourg, [7] vol. sxxvi. no. 13 
(1889), p. 4, pi. i. figs. 8, 9. 

b2 



ACA1TTH0DII. 



proximally in a smaller, abruptly truncated expansion. This 
element has a thick, smooth, calcined surface, and its long axis 

Fig. 2. 




Skeleton of pectoral fin of Acanthodes bronni, Ag. 
&, basal cartilage ; r, fibrous rays ; s, anterior spine. 

seems to have been originally more or less vertical, while there is no 
evidence of a connection with its fellow of the opposite side. By 
Huxley, Kner, Egerton, and others, this has been regarded as a 
representative of the pectoral arch ; and the interpretation may 
appear at first sight justified by the relatively large size of the car- 
tilage in some Diplacanth genera. To the present writer, however, 
the element in question seems to pertain to the basipterygium ; for 
it exhibits the same relative size and position as the basal cartilage 
in the spinous dorsal fins of several sharks ; and in a well-preserved 
example of another Acanthodian, Pareocus falcatus (No. P. 130, 
p. 35), a much larger, expanded, triangular element, more delicate, 
apparently meets its fellow in the middle line, and occupies the 
position with respect to the spine that a pectoral arch might be 
expected to hold. No other cartilage is recognizable, but at a short 
distance below the supposed basipterygium there occurs a close series 
of short, fine dermal fin-rays (r), sometimes appearing as the fringe 
of a short obtuse lobe ; and it may be that these mark the precise 
limit of the endoskeletal part of the appendage. 

As often shown in the type species 1 , the anterior part of the 
lower lobe of the caudal fin is supported by a series of long, stout, 
basal cartilages (? haemal spines), each apposed to a short haemal 
arch, but distinctly separated from the latter. The Acanthodian 
caudal fin thus presents a resemblance to the corresponding fin of 
certain Selachians, e. g. Mustelus antarcticus 2 . 

1 Kner, Sitzungsb. k. k. Akad. Wiss. Wien, math.-naturw. Cl. vol. Mi. pt. i. 
pi. v. fig. 2, pi. vii. fig. 1. 

2 Mivart, Trans. Zool. Soc. vol. x. (1879) p. 441, pi. lxxiv. fig. 6. 



ACANTHODID^. O 

The squamation appears to be of equal fineness over the whole of 
the trunk, there being no fulcral scales even on the upper caudal 
lobe ; while the only diminution in the size of the quadrate granules 
occurs in this region and towards the distal margins of the fins. 
The scales are either rectangular or slightly rhomboidal, with a flat- 
tened or faintly excavated external surface, usually smooth ; and 
their attached surface exhibits a gentle convexity. A single lateral 
line occurs high on each flank, marked not by any tubular or other 
excavation of the scales, but by the ridge-like displacement of two 
series, between which the organ originally extended. The supposed 
evidence of additional sensory canals appears to the present writer 
to be due to a misinterpretation of the displaced dorsal and ventral 
ridges, which exhibit no median series of scales. 

The evolution of the paired fins in the successive species of Acan- 
thodes, as defined below, is of some interest. In the Upper Devonian 
representatives of the genus the pelvic fins are not much inferior in 
size to the pectorals, and are placed nearly midway between the 
latter and the anal. In the Lower Carboniferous A. nitidus the 
pelvic fins are similarly placed, but reduced in size. In the Upper 
Carboniferous A. wardi the same fins are not only further reduced, 
but occupy a more forward position, while the pectorals are much 
enlarged. In the Lower Permian species the pelvic fins become 
insignificant and the pectoral fins enormous, while the two pairs are 
even more closely approximated than in the earlier forms. 

Acanthodes bronni, Agassiz. 

1832. Acanthoessus bronnii, L. Agassiz, Neues Jahrb. p. 149. 
1833-35. Acanthodes bronnii, L. Agassiz, Poiss. Foss. vol. ii. pt. i. 

pp. 20, 124, P l. i. 
1848. Holacanthodes gracilis, E. Beyrich, Monatsb. Beri. Akad. p. 24. 
1857. Acanthodes gracilis, F. Roemer, Zeitschr. deutsch. geol. Ges. 

vol. ix. p. 65, pl. iii. 
1857. Acanthodes bronnii, F. H. Troschel, Verhandl. naturh. Ver. preuss. 

Rheinl. u. Westph. vol. xiv. p. 2, pis. i., ii. figs. 1-13. 
1861. Acanthodes gracilis, H. B. Geinitz, Dyas, p. 21. 
1864. Acanthodes bronnii, E. Weiss, Zeitschr. deutsch. geol. Ges. vol. 

xvi. p. 291. 
1868. Acanthodes bronnii and A. gracilis, R. Kner, Sitzungsb. k. k. 

Akad. Wiss. Wien, math.-naturw. CI. vol. lvii. pt. i. p. 303, pis. 

v.-viii. 

Type. Imperfect fish; olim H. G. Brown Collection. 

The type species, attaining a maximum length of about 0*3. 
Body much elongated and slender, the maximum depth being con- 
tained about six or seven times in the total length. Pectoral fin- 



i 



ACANTHOPIT. 

spines broad and robust, much laterally compressed, very slightly 
arched, with ono very prominent, oblique, lougitudinal ridge and 
groove and several minor grooves ; pelvic fin-spines relatively small, 
scarcely attaining one quarter the size of the pectorals. Pelvic fins 
placed far forwards, the length of the space between this pair and 
the pectorals equalling about one half that of the space between it 
and the anal. Anal fin-spine half as large as the pectoral ; dorsal 
still slightly smaller, situated a short distance behind the anal. 
Scales smooth or with a median pit. 

According to the latest memoir on the subject — that by Kner — 
A. bronni is distinguished from the so-called A. gracilis by its less 
slender proportions, its relatively smaller scales, and the more poste- 
rior situation of the pelvic fins. The two forms, however, are deter- 
mined as occurring together both in East and West Germany ; and 
all the examples figured by Kner from Saarbriick (Rhenish Prussia) 
are named A. gracilis. 

An examination of the series of specimens mentioned below, sug- 
gests to the present writer that the comparatively robust appearance 
of the type specimens of A. bronni and other fossils in the Saar- 
briick nodules assigned to this species is due entirely to imperfect 
preservation. The fishes have been buried in a coiled-up state, 
while the skin with its scales has been displaced by crushing ; and, 
when a sharp outline is distinguishable, the body appears quite as 
slender as that of the well-preserved typical examples of A. gracilis 
occurring in the fine shale of Klein Neundorf. The size of the 
scales is also inconstant, and we can therefore, as yet, determine 
only one species in the German Rothliegendes. 

Kner describes, as characteristic of this species, the presence of a 
small spine bounding the posterior margin of the pectoral fin. The 
statement, however, seems to have been based upon a mistake in 
observation ; for the specimens in the Collection exhibit no such 
spine, and in one case cited (Kner, pi. v. fig. 1) it may well be a 
fragment of an ordinary pectoral, while in the other case (Kner, 
pi. vi. fig. 1) it is probably the pelvic fin-spine somewhat displaced. 

Form. 6f Loc. Lower Permian (Ptotbliegendes) : Germany. 

22658 a. A small specimen completely coiled upon itself, in a 
nodule ; Saarbriick, Rhenish Prussia. The circum- 
orbital plates and the gill-arches are shown in the region 
of the head. Purchased, 1848. 

40048-50. One nodule with obscure remains of a fish of moderate 
size ; another with remains of a large head and anterior 
portion of the abdominal region ; and a third nodule con- 



ACANTHODID^. / 

taining a small coiled fish, tolerably well preserved ; 
Lebach, Khenish Prussia. Purchased, 1866. 

P. 1324, P. 4477. Nodule with an imperfect fish resembling that 
figured by Agassiz, torn. cit. pi. i. fig. 1 ; Lebach. 

Egerton and Ennislcillen Colls. 

P. 1324 a, P. 3249. Specimen in a large nodule, not coiled, and 
only slightly crushed ; Lebach. In the region of the head 
are remains of the circumorbital plates and branchial 
arches ; and the pectoral, pelvic, and dorsal fin-spines are 
more or less imperfectly preserved. 

Egerton and Ennislcillen Colls. 

P. 4477 a. Half of nodule containing the head and the greater 
portion of the coiled-up trunk ; Lebach. Some of the 
circumorbital plates and remains of the granular dermal 
covering of the head are preserved : fragments of branchial 
arches occur below and behind the head ; and all the fin- 
spines are shown, at least in part. Ennislcillen Coll. 

P. 6192. Five small specimens, one being in counterpart; Lebach. 

Goldenberg Coll. 

P. 6192 a. Remains of head and branchial arches ; Lebach. 

Goldenberg Coll. 

33060, 33063. Five imperfect fishes, variously broken and distorted, 
preserved in shale, and displaying all the principal cha- 
racters of the species ; Klein Neundorf, near Lowenberg, 
Silesia. Purchased, 1858. 

P. 1325. Four specimens in a similar state of preservation, but 
mostly finer ; Klein Neundorf. Egerton Coll. 

P. 3248. Small specimen, wanting extremity of tail ; Klein Neundorf. 
The sketch of the pectoral fin given in fig. 2 is chiefly 
based upon this specimen. Ennislcillen Coll. 

38159. Caudal region of a very large fish, doubtfully of this species ; 
Klein Neundorf. 

Presented by Sir Roderick I. Murchison, K.C.B., 1864. 

Acanthodes rouvillei, Sauvage. 

1883. Acanthodes rouvillei, H. E. Sauvage, Bull. Soc. Geol. France, [3] 
vol. xi. p. 475, pi. x. fig. 1. 

Type. Nearly complete fish. 

A small species closely allied to A. bronni. Body much elongated 



S ACA.XTHODIT. 

and slender, the head occupying about one sixth of the total length. 
Pectoral fin-spines relatively large, arched, and longitudinally 
striated ; pelvic fin-spines very small, about one fifth as large as the 
pectorals, separated from the latter by a space much less than one 
half of the distance between them and the anal. Dorsal and anal 
fin-spines almost directly opposed, of nearly equal size, and more 
than half as large as the pectoral spine. [Scales unknown.] 

The remarkable form of the head, as described by Sauvage, is 
doubtless due to imperfect preservation ; and the supposed lower 
jaw has much the appearance of the styliform cartilage termed 
ceratohyal by the present writer. 

Form. 6f Loc. Permian : Lodeve, France. 

Not represented in the Collection. 

Acanthod.es wardi, Egerton. 

1866. Acanthodes wardi, Sir P. Egerton, Quart. Journ. Geol. Soc. vol. 

xxii. p. 468, pi. xxiii. . 
1871. Acanthodes wardii, J. Thomson, Trans. Geol. Soc. Glasgow, vol.iv. 

p. 57, pi. iv. 

1875. Acanthodes wardi, J. Ward, [Proc] N. Staffs. Nat. Field-Club, 
p. 241. 

1876. Acanthodes wardi, J. W. Davis, Quart. Journ. Geol. Soc. vol. 
xxxii. p. 335. 

1890. Acanthodes wardi, J.Ward, Trans. N. Staffs. Inst. Mining Engin. 

vol. x. p. 157, pi. v. fig. 2. 
1890. Acanthodes wardi, R. H. Traquair, Proc. Roy. Soc. Edinb. vol. 

xvii. p. 388. 

Type. Imperfect fish ; collection of John Ward, Esq., Longton. 

A species closely resembling A. bronni in form and proportions. 
Pectoral fin-spines broad and robust, much laterally compressed, 
with a single groove and faint ridge nearly parallel to the anterior 
border and disappearing distally ; other spines similar. Pelvic fin- 
spines relatively small, about one quarter the size of the pectorals ; 
pelvic fins extremely elongated, arising at a point about three 
quarters as far from the pectoral fins as from the anal. Anal fin- 
spine half as large as the pectoral ; dorsal still slightly smaller, 
placed a short distance behind the anal. Scales smooth, sometimes 
faintly hollowed mesially. 

Form. 6f Loc. Coal-Measures : Staffordshire and Scottish Coal- 
fields. 

36891. Remains of small fish, displaying proportions of pectoral and 
pelvic fin-spines ; Deep-mine Ironstone, Longton, N. Staf- 
fordshire. Purchased, 1862. 



ACANTH0D1DJE. 



9 



P. 236. Fragment, showing circumorbital plates ; Longton. 

Weaver Jones Coll. 

P. 1326. Caudal region of a large fish, and the greater portion of 
two small fishes ; Longton. Egerton Coll. 

P. 1327. Portion of head and branchial arches, being the counter- 
part of the specimen figured by Egerton, loc. cit. fig. 2 ; 
Longton. Appearances in this fossil suggest that the gill- 
clefts were well separated by narrow bands of scale- 
covered skin. Egerton Coll. 

P. 3250. Imperfect specimen of moderate size, and the caudal region 
of a small individual; Longton. EnnisJcillen Coll. 

P. 5178. Well-preserved caudal region ; Longton. Purchased, 1885. 

An Acanthodian spine from the Coal-Measures of Buxiere-les- 
Mines, Allier, France, closely resembling the pectoral of Acanthodes 
wardi, is named Onchus simplex, TL E. Sauvage, Bull. Soc. Geol. 
France, [3] vol. vi. (1878) p. 625, pi. xi. fig. 4. Similar spines, of 
small size, also occur in the Coal-Measures of Nova Scotia (Geol. 
Survey Museum, Ottawa, and Bedpath Museum, Montreal). 

Acanthodes nitidus, sp. nov. 

Type. Imperfectly preserved fish ; British Museum. 

Body much elongated and slender, the maximum depth being 
contained about six times in the total length. Pectoral fin-spines 
broad, much laterally compressed, with a single groove and faint 
ridge nearly parallel to the anterior border and disappearing dis- 
tally ; other spines similarly grooved but somewhat more tumid in 
the proximal half. Pelvic fin-spines relatively small, about one 
third as large as the pectorals, situated halfway between the latter 
and the anal. Anal fin-spine at least half as large as the pectoral, 
larger than the dorsal, which is placed immediately behind. Scales 
smooth, the surface faintly excavated or flat. 

So far as known, this species is readily distinguished from the 
closely allied A. wardi by the relatively larger size and somewhat 
more remote situation of the pelvic fins. 

Form. Sf Loc. Calciferous Sandstones : Dumfriesshire. 

P. 4057. The type specimen, being an imperfectly preserved fish, 
0*22 in length, showing large portions of all the fin-spines 
in position, and displaying the characters noted in the 
diagnosis ; Eskdale. Purchased, 1883. 



10 ACAOTHODII. 

P. 4058. Imperfect pectoral tin-spine and scattered scales ; Eskdale. 

Purchased, 1883. 

P. 5979. Greater portion of a smaller fish, preserved in counterpart, 
with indications of slender calcined neural arches ; 
Eskdale. Purchased, 1889. 

A fragment of squamation from the Calciferous Sandstones of 
Wardie, near Edinburgh, is named Acanthodes sulcatus, L. Agassiz, 
Pois8. Foss. vol. ii. pt. i. (1835) p. 125, pi. i c. figs. 1, 2. The 
specimen is preserved in the University Museum, Oxford, and must 
be regarded as specifically indeterminable. Under the same name, 
however, more satisfactory Acanthodian fossils have been briefly 
noticed by R. H. Traquair (Proc. Roy. Soc. Edinb. 1890, p. 392) 
from the Calciferous Sandstones of several localities in Fife and the 
Lothian s, these being regarded as distinguishable from A. wardi 
only by " a somewhat greater straightness and slenderness of the 
' styliform ' bone." 

Acanthodes pygmseus, Fritsch. 

1875. Acanthodes pygmceus, A. Fritsch, Sitzungsb. k. bohm. Ges. Wiss. 
p. 74. 

Type. Nearly complete fish ; Royal Bohemian Museum, Prague. 

A small species, about 0"08 in length, not yet defined, but to be 
described in a forthcoming part of Fritsch's ' Fauna der Gaskohle.' 
The scales are relatively large and smooth, and the median fin- 
spines long and slender. 

Form. &f Loc. Lower Permian : Bohemia. 

P. 4157. Imperfect caudal region, showing dorsal and anal fin- 
spines, labelled by Prof. Dr. F. Roemer ; Nyfan, near 
Pilsen. Enniskillen Coll. 

Acanthodes concinnus, Whiteaves. 

1887. Acanthodes concinnus, J. F. Whiteaves, Trans. Roy. Soc. Canada, 
vol. iv. sect. iv. p. 107, pi. x. fig. 1. 

1889. Acanthodes concinnus, J. F. Whiteaves, ibid. vol. vi. sect. iv. 
pi. v. fig. 2. 

1890. Aca?ithodes concinnus, R. H. Traquair, Geol. Mag. [3] vol. vii. 
p. 16. 

Type. Imperfect fish ; Geological Survey of Canada, Ottawa. 

A small species, attaining a maximum length of about 0-15 ; 
head occupying approximately one sixth of the total length. Fin- 
spines short and slender in proportion to the size of the fish, each 






ACANTHODIDiE. 11 

ornamented with about four longitudinal grooves. Pectoral spines 
stouter and longer than the others ; pelvic spines small ; anal spine 
slightly in advance of the dorsal. Scales minute, with faint dia- 
gonal striations. 

Form. <$f Loc. Upper Devonian : Scaumenac Bay, P. Q,., Canada. 

Not represented in the Collection. 

The following small Devonian species have recently been assigned 
by R. H. Traquair to a distinct genus, Mesacanthus, characterized 
by the presence of a minute pair of free spines on the ventral sur- 
face between the pectoral and pelvic fins. The proportions of the 
paired fins are certainly somewhat different from those of the typical 
Acanthodes, and decided points of generic distinctness may even- 
tually be discovered. At present, however, we propose to retain 
the long-accepted nomenclature ; more especially as the minute 
additional pair of spines is not observable in any of the specimens 
mentioned below, except a few examples of A. mitchelli. 



Acanthodes pusillus, Agassiz. 
[Plate I. figs. 5, 6.] 

1844. Acanthodes pusillus, L. Agassiz, Poiss. Foss. V. G. R. p. 36, 

pi. xxviii. figs. 8-10. 
1888. Mesacanthus pusillus, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 512. 

Type. Imperfect fish ; Forres Museum. 

A very small species, the largest specimen in the Collection (PL I. 
fig. 5) measuring not more than 0*06 in extreme length. Body 
elongated and slender, the maximum depth being contained about 
six or seven times in the total length ; caudal lobe extremely 
elongated. Pelvic fins large, midway between the pectorals and the 
anal ; pelvic spines not less than half the size of the pectorals, and 
two thirds as long as the anal spine. Dorsal fin arising behind the 
origin of the anal, slightly larger than the latter. 

In the original description of A. pusillus, Agassiz mentions the 
presence of a series of small spines upon the lower border of the 
caudal region. The character, however, is not alluded to by Egerton 
when comparing this species with A. peachi, and it is not exhibited 
by any of the specimens enumerated below. 

Form. Sf Loc. Lower Old Red Sandstone : Banffshire, Scotland. 

35784-5. Two specimens, exhibiting the elongated upper caudal 
lobe ; Tynet Burn. Purchased, 1860. 



iZ ACANTHODII. 

35786. A comparatively large specimen, shown, of the natural size, 
in PI. I. fig. 5 ; Tynet Burn. The fish is distorted, and 
the outlines are somewhat obscured by the displacement 
of the scales ; but several details are exhibited. In the 
head, the cartilages of the upper and lower jaws are indi- 
cated, and the ring of circumorbital dermal plates is 
preserved. Only a portion of one pectoral spine is observ- 
able ; but the pelvic fin of the left side, with its spine, is 
complete, and exhibits a very long base-line. The large 
anal spine also occurs in position in front of a much elon- 
gated fin ; and there is a fragment of the dorsal spine in 
its ordinary position. The upper caudal lobe is somewhat 
broken towards the extremity, but otherwise well pre- 
served, as is also the greater portion of the caudal fin. 

Purchased, 1860. 

43019. A small coiled-up specimen, preserved in counterpart ; 
Tynet Burn. Purchased, 1871. 

P. 1329. Pour small specimens, two being associated in one nodule. 
The largest of the latter is shown, of the natural size, in 
PL I. fig. 6 ; Tynet Burn. Egerton Coll. 

Acanthodes peachi, Egerton. 

1861. Acanthodes peachi, Sir P. Egerton, Figs. & Descrips. Brit. Organic 
Remains (Mem. Geol. Surv.), dec. x. p. 57, pi. vi. figs. 1, 2. 

1861. Acanthodes coriaceus, Sir P. Egerton, ibid. p. 59, pi. vi. figs. 3-5. 
[Museum of Practical Geology.] 

1888. Mesacanthus peachii, R. H. Traquair, Geol. Mag. [3] vol. v. p. 512. 

Type. Nearly complete fish ; Museum of Practical Geology, 
London. 

A very small species, attaining a maximum length of about 0-06. 
Body more robust than in A. pus-'dlus, the greatest depth being con- 
tained about five or six times in the total length. Pelvic fins large, 
midway between the pectorals and the anal ; pelvic spines smaller 
than the pectorals, but almost or quite as long as the anal spine. 
Dorsal fin arising slightly behind the anal, and much larger than 
the latter. 

Form. Sf Loc. Lower Old Red Sandstone : Caithness, Scotland. 

33148. Imperfect specimen, showing the dorsal, anal, and pelvic 
spines, with portions of the pectorals and pectoral basi- 
pterygium ; Thurso. Purchased. 



ACANTHODID^. 13 

49668-9. One very stout specimen and an imperfectly preserved 
caudal region, with impression of the head and abdominal 
region; Thurso. Purchased, 1879. 

43967. Crushed fish, showing all the fin-spines ; Thurso. 

Purchased, 1872. 

38583. Slab with remains of several individuals. Purchased, 1864. 

Acanthodes mitchelli, Egerton. 
[Plate I. fig. 7.] 

1860. Acanthodes antiquus, Sir P. Egerton, Rep. Brit. Assoc. 1859, 
Trans. Sect. p. 116 (name only). 

1861. Acanthodes mitchelli, Sir P. Egerton, Rep. Brit. Assoc. 1860, 
Trans. Sect. p. 77 ; and Figs. & Descrips. Brit. Organic Remains 
(Mem. Geol. Surv.), dec. x. p. 61, pi. vii. 

1864. Acanthodes mitchelli, J. Powrie, Quart. Journ. Geol. Soc. vol. xx. 

p. 419. 
1870. Acanthodes mitchelli, J. Powrie, Trans. Edinb. Geol. Soc. vol. i. 

p. 288, pi. x. fig. 1. 
1888. Mesacanthus mitchelli, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 512. 

Type. Complete fish ; British Museum. 

A very small species, attaining a maximum length of 0*065. 
Body elongated and slender, the greatest depth being contained 
about six times in the total length ; cranial roof very coarsely 
rugose or consisting of large, irregular, tesserae-like membrane bones. 
Pelvic fins large, situated somewhat nearer to the anal than to the 
pectorals ; a pair of minute spines in advance of the pelvic pair. 
Pelvic spines about half as large as the pectorals, and two thirds as 
long as the anal. Dorsal fin arising behind the anal, larger than 
the latter. 

Form. Sf Loc. Lower Old Red Sandstone : Forfarshire. 

P. 560, P. 1330. Type specimen and a smaller more imperfect fish ; 
Farnell, Forfarshire. The minute intermediate ventral 
spines are shown in Egerton's outline sketch, but not in 
the detailed enlarged figure, and apparently not in the 
original specimen. The second fossil exhibits these 
spines. Egerton Coll. 

35909. Two contorted fishes ; Farnell. 

Presented by James Powrie, Esq., 1861. 

38594. Almost complete fish, lateral aspect, shown, of the natural 
size, in PI. I. fig. 7. 

Presented by James Powrie, Esq., 1864. 



1 4 ACANTHODII. 

38514-15. Crushed specimen, and another fish, lateral aspect ; 
Turin Hill, Forfar. Purchased, 1864. 

41362. Very small fish ; Turin Hill. Purchased, 1869. 

46307. Four specimens ; Turin Hill. Purchased, 1875. 

P. 126, P. 140. Contorted and crushed small individual, in counter- 
part, and an imperfect large fish ; Turin Hill. 

Purchased, 1880. 

P. 1331. Two specimens; Turin Hill. Egerton Coll. 

P. 5081. Well-preserved specimen ; Turin Hill. 

Presented by J. E. Lee, Esq., 1885. 

Acanthodes affinis, Whiteaves. 

1887. Acanthodes mitchelli(?) ox Acanthodes affinis, J. F. Whiteaves, 
Trans. Roy. Soc. Canada, vol. iv. sect. iv. p. 107. 

1889. Acanthodes affinis, J. F. Whiteaves, Trans. Roy. Soc. Canada, 
vol. vi. sect. iv. p. 91, pi. v. fig. 1. 

1890. Mesacanthus affinis, R. H. Traquair, Geol. Mag. [3] vol. vii. 
p. 16. 

Type. Nearly complete fish ; Geological Survey of Canada, 
Ottawa. 

A very small species, about 0*04 in length. Body elongated and 
slender, the greatest depth being contained about five times in the 
total length. Pelvic fins large, situated somewhat nearer to the 
anal than to the pectorals ; pelvic spines more than half as large as 
the pectorals, and about equal in size to the anal. Dorsal spine 
slightly behind the anal, scarcely larger than the latter. 

Form. Sf Loc. Upper Devonian : Scaumenac Bay, P. Q., Canada. 

P. 5975. Typical specimen, 0*03 in length. Purchased, 1889. 

Two small Acanthodian fishes of the same type as the preceding 
are also known from supposed Devonian strata in Siberia, but there 
are no examples in the Collection. They are described as follows : — 

Acanthodes lopatini, J. V. Rohon, Mem. Acad. Imp. Sci. St. Peters- 
bourg, [7] vol. xxxvi. no. 13 (1889), p. 3, pi. i. figs. 1-3, 
6-9, 11, 12, 15-17. — Devonian (?) ; Isyndschul, near 
River Seresch, Govt, of Tomsk, Siberia. [Imperfect fishes ; 
Imperial Academy of Sciences, St. Petersburg.] 

Acanthodes parvulus, J. V. Rohon, ibid. p. 7, pi. i. fig. 5. — Ibid. 
[Imperfect fish, displaying caudal region ; Imperial Acad- 
emy of Sciences, St. Petersburg.] 



/ 



ACANTHODIDJE. 



15 



A mass of scales, of indeterminable genus, from the Genesee 
Shale (Upper Devonian), Glenville, New York, is named Acanthodes 1 ? 
prists J. M. Clarke, Bull. U.S. Geol. Surv. no. 16 (1885), p. 42. 



Genus ACANTHODOPSIS, Hancock & Atthey. 
[Ann. Mag. Nat. Hist. [4] vol. i. 1868, p. 364.] 

[Form of trunk and arrangement of fins unknown.] Dentition 
powerful, consisting of few large, laterally compressed, triangular 
teeth. Pectoral fin-spines relatively large. 

This genus was originally founded upon some portions of jaws 
from the Coal-Measures of Northumberland, met with in association 
with pectoral fin-spines and shagreen, indistinguishable from the 
corresponding parts of Acaniliodes wardi. The fish just mentioned 
was thus regarded as the type species of the genus, while a supposed 
second form, of larger size, received the name of Acanthodopsis 
egertoni. 

Acanthodopsis wardi, Hancock & Atthey. 

1868. Acanthodopsis wardi, Hancock & Atthey, Ann. Mag. Nat. Hist. 

[4] vol. i. p. 364, pi. xv. fig. 6 (reprinted in Nat. Hist. Trans. 

Northumb. & Durham, vol. iii. 1870, p. 103, pi. ii. fig. 6). 
1868-70. Acanthodopsis egertoni, Hancock & Atthey, ibid. p. 367, and 

ibid. p. 107. [Jaw ; Newcastle-upon-Tyne Museum.] 
1880. Acanthodopsis, R. H. Traquair, Proc. Roy. Phys. Soc. Edinb. 

vol. v. p. 117. 
1890. Acanthodopsis wardi, P. H. Traquair, Proc. Roy. Soc. Edinb. 

vol. xxvii. p. 388. 

Type. Jaws, &c. ; Newcastle-upon-Tyne Museum. 

The type species, having jaws attaining a length of about 0*5. 
Teeth at least as broad as deep, marked with fine vertical wrinkles, 
and confluent at the base ; about six or eight in number on each 
side above and below, largest in the middle of the ramus, and 
without intermediate denticles. Pectoral spines long and laterally 
compressed, smooth, with an antero -lateral longitudinal groove. 
Dermal granules smooth. 

Form. Sf Loc. Coal-Measures : Northumberland and Midlothian. 

41202. Portion of jaw with two teeth; Low Main Seam, Newsham, 
near Newcastle. Presented by T. P. Barkas, Esq., 1868. 

P. 786-7. Three fragments of jaws, one also showing the proximal 
end of a ceratohyal ; Newsham. Egerton Coll. 



16 AC.VNTH0D11. 

P. 3264. Two imperfect mandibular rami with ceratohyals, a jaw- 
fragment, and a detached ceratohyal ; Newsham. 

Enniskillen Coll. 

The following pectoral fiu-spines may pertain either to Acantlio- 
dopsis or to a large form of Acanihodes : — 

P. 1328. Imperfect spine, slightly arched, with a single longitudinal 
furrow near the anterior margin, preserved for a length 
of 0-11 ; also two associated portions of similar spines ; 
Coal-Measures, Lowmoor, Yorkshire. Egerton Coll. 

P. 3252. Two imperfect specimens, one larger, one smaller ; Low- 
moor. Enniskillen Coll. 

P. 2285. Fragment of large spine ; Coal-Measures, Carluke, Lanark- 
shire. Presented by George Griffiths, Esq., 1882. 

Genus CHEIRACANTHUS, Agassiz. 

[Poiss. Foss. vol. ii. pt. i. 1835, p. 125.] 

Body fusiform, laterally compressed. Teeth minute or absent ; 
orbit with ring of four circumorbital dermal plates. Pectoral 
fins large ; pelvic pair w^ell developed. A single dorsal fin, arising 
opposite the space between the pelvic fins and the anal. 

Cheir acanthus murchisoni, Agassiz. 

1835. Cheiracanthus murchisoni, L. Agassiz, Poiss. Foss. vol. ii. pt. i. 

p. 126, pi. i c. figs. 3, 4. 
1835. Cheiracanthus minor, L. Agassiz, ibid. pt. i. p. 127, pi. i c. fig. 5. 
1844. Cheiracanthus microlepidotus, L. Agassiz, Poiss. Foss. V. G. R. 

p. 38, pi. xv. figs. 1-3. [British Museum and Forres Museum.] 
1848. Chiracanthus lateralis, F. M'Coy, Ann. Mag. Nat. Hist. [2] 

vol. ii. p. 300. [Woodwardian Museum, Cambridge.] 
1848. Chiracanthus pulverulentus, F. M'Coy, ibid. p. 299. [Ibid.] 
1855. Chiracanthus lateralis, F. M'Coy, Brit. Palseoz. Foss. p. 582. 
1855. Chiracanthus microlepidotus, F. M'Coy, ibid. p. 583. 
1855. Chiracanthus minor, F. M'Coy, ibid. p. 583. 
1855. Chiracanthus murchisoni, F. M'Coy, ibid. p. 583. 
1855. Chiracanthus pulverulentus, F. M'Coy, ibid. p. 583, pi. iiB. fig. 2. 
1888. Cheiracanthus murchisoni, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 512. 

Type. Imperfect fish ; unknown (olim Murchison Collection). 

The type species, usually attaining a length of about 0'16-0'2, 
but occasionally measuring as much as # 3. Body elongated and 
slender, the greatest depth being nearly equal to the length of the 



ACANTHODTDiE. H 

head with branchial apparatus, and contained about live times in. 
the total length. Fin-spines slender, the length of the pectorals 
less than the depth of the trunk at their point of insertion, and the 
pelvic spines scarcely more than half as long as these. Pelvic fins 
with much elongated base-line, arising midway between the pec- 
torals and the anal ; anal spine about equal in size to the pelvic 
spines, and the anal fin separated by a considerable space from the 
caudal. Dorsal fin very large, arising about midway between the 
pelvic fins and the anal. Scales marked with very fine, straight or 
irregularly wavy striae. 

Form. <$f Loc. Lower Old fted Sandstone : Banffshire, Nairnshire, 
Cromarty, Hoss-shire, Caithness, and the Orkney Isles, Scotland. 

P. 1355. Two crushed specimens in nodules ; Gamrie, Banffshire. 

Egerton Coll. 

P. 1355 a-b, P. 3257 a-b. Two split nodules, each containing a 
crushed and imperfectly preserved fish ; Gamrie. 

Egerton and Enniskillen Colls. 

36063. Small fish, laterally crushed, showing the pelvic, dorsal, and 
anal fins, and portions of the pectorals and caudal ; Tynet 
Burn, Banffshire. Purchased, 1861. 

41412, 41412 a. Small specimen, showing partial impressions of 
the muscular myotomes, and a fish about 0*17 in length 
with well-preserved remains of the pectoral, pelvic, and 
anal fins ; Tynet Burn. Purchased, 1869. 

P. 1356. Three specimens more or less crushed and distorted, one 
displaying the circumorbital dermal plates ; Tynet Burn. 

Egerton Coll. 

P. 1356 a, P. 3254. Split nodule with greater portion of a fish 
wanting the caudal fin ; Tynet Burn. In this specimen 
the cartilages of the jaws and portions of the basipterygium 
are exhibited. Egerton, and Enniskillen Colls. 

P. 544. Type specimen of Cheiracanthus microlepidotus, figured by 
Agassiz, loc. cit, fig. 2 ; Lethen Bar, near Nairn. 

Egerton Coll. 

28865. Two small crushed and contorted fishes, slightly larger than 
the last ; Lethen Bar. Purchased, 1854. 

P. 1351. Imperfect fish about 0-16 in length ; Lethen Bar. 

Egerton Coll. 

P. 4614. Remains of a smaller fish, determined by Agassiz as 
C. microlejpidotus ; Lethen Bar. Enniskillen Coll. 

PAET II. C 



18 ACA2TTH0DII. 

P. 4613. Fish, wanting head ; Lethen Bar. EnnisJcillen Cell. 

P. 5963. Small specimen, showing w T ell-preserved pelvic fins ; 
Lethen Bar. Purchased, 1889. 

49183. Fish with crushed head, lateral aspect, in counterpart, 
wanting the caudal fin ; Lethen Bar. Purchased, 1878. 

50105. Specimen originally about 0*26 in length, showing all the 
fins, but wanting the upper lobe of the tail and portions 
of the head; Lethen Bar. Purchased, 1879 . 

P. 4039. A well-preserved still larger fish, 0-3 in length ; Lethen 
Bar. Purchased, 1883. 

19061-63. Three much-crushed imperfect specimens ; Cromarty. 

Purchased, 1845. 

19801. Two similar fossils ; Cromarty. Purchased, 1845. 

P. 1354. Comparatively well-preserved specimen ; Cromarty. 

Egerton Coll. 

P. 3256. Imperfect fish, showing all the fins ; Cromarty. 

EnnisJcillen Coll. 

43460. Trunk of small fish ; Eathie Bay, Boss-shire. 

Presented by Kenneth Murchison, Esq., 1872. 

P. 1353. Crushed specimen and fragment ; Edderton, near Tain, 
Eoss-shire. Egerton Coll. 

P. 186-7. A fine specimen, 0165 in length, and a small crushed 
individual displaying the fin-spines ; Caithness. 

Purchased, 1881. 

35046. Nearly complete fish, preserved in black flagstone and having 
a bituminous appearance ; Stromness, Orkney. 

Purchased, 1860. 

38730, 41360. Two similar but larger specimens ; Orkney. 

Purchased, 1865, 1869. 

39193. Pish wanting head and portion of tail ; Skaill, Orkney. 

Bowerbank Coll. 

P. 1347-49. Four imperfect specimens ; Orkney. Egerton Coll. 

P. 4475. Small fish in similar state of preservation ; Stromness, 
Orkney. EnnisJcillen Coll. 

P. 4476. Two imperfect larger specimens ; Belyacreugh, Orkney. 

EnnisJcillen Coll. 



\CA3TH0D1D.T?. 19 

Cheiracanthus latus, Egerton. 
1861. Cheiracanthus latus, Sir P. Egerton, Figs. & Descrips. Brit. 

Organic Remains (Mem. Geol. Surv.), dec. x. p. 73, pi. x. 
1888. Cheiracanthus latus, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 512. 

Type. Nearly complete fish. 

A species attaining a length of about 0-16. Body comparatively 
short and stout, the greatest depth exceeding the length of the head 
and contained about four times in the total length. Fin-spines 
stout, the length of the pectorals at least equalling the depth of the 
trunk at their point of insertion, and the pelvic spines two thirds as 
long as these. Pelvic fins with elongated base-line, arising midway 
between the pectorals and the anal ; anal spine about equal in size 
to the pelvic spines, and the anal fin extending to the base of the 
rery large caudal. Dorsal fin as large as the pectorals, arising mid- 
way between the pelvic fins and the anal. Scales marked with few 
large, rounded, parallel ridges and furrows. 

Form. Sf Log. Lower Old Red Sandstone : Banffshire, Scotland. 

The following specimens were all obtained from nodules in Tynet 
Burn : — 
35052. Imperfect fish, wanting the tail. Purchased, 1860. 

35022-23. Two imperfect crushed specimens. 

Presented by the Duke of Richmond, 1859. 

35985. Remains of a large fish. Purchased, 1861. 

36010, 36062. Two specimens of moderate size. Purchased, 1861. 

36064-65. Small specimen, in counterpart. Purchased, 1861. 

37383. Pish wanting the head and the end of the tail. 

Purchased, 1863. 

43015-17. Three crushed specimens, the second showing circum- 
orbital plates, and the scales of the third exhibiting traces 
of fine striations upon the usual coarse ridges and furrows. 

Purchased, 1871. 

43273 a-b, 43274. Specimen in counterpart, wanting the head, and 
a crushed individual with very powerful spines. 

Purchased, 1871. 
P. 1350. Pour specimens. Egerton Coll. 

P. 3253. Three specimens. Enniskillen Coll. 

P. 6075. Imperfect specimen, showing all the spines. 

Presented by F. Harford, Esq., 1889. 
c2 



20 ACANTHODII. 

Cheiracanthus grandispinus, M'Coy. 

848. Chiraeanthus (jrandispiims, F. M'Coy, Ann. Mag. Nat. Hist. [2] 

vol. ii. p. 300. 
1855. Chiraeanthus </ra?idispinus, F. M'Coy, Brit. Palseoz. Foss. p. 582, 

pi. iis. fig. 1. 
1888. Cheiracanthus grandispinus, R. H. Traquair, Geol. Mag. [3] 

vol. v. p. 512. 

Type. Imperfect fish ; Woodwardian Museum, Cambridge. 

An imperfectly known species, attaining a length of about 0*25- 
0-3. Body comparatively deep and robust. Fin-spines extremely 
stout and longitudinally ribbed, the length of the pectorals not 
equalling the depth of the trunk at their point of insertion. Pelvic 
fins arising midway between the pectorals and the anal, and the 
dorsal midway between the pelvics and the anal. Scales relatively 
small. 

Form. S[ Log. Lower Old Red Sandstone : Orkney Isles, Scotland. 

39186. Middle portion of trunk, with pelvic, dorsal, and anal spines. 

Bowerbcmk Coll. 

41130. Imperfect head and trunk, wanting the extremity of the 
caudal region. Bryson Coll. 

P. 178-9. Two imperfectly preserved specimens, the first showing 
remains of the head and anterior portion of the abdominal 
region, the second only wanting the extremity of the tail. 

Purchased, 1881. 



Family ISCHNACANTHIDiE. 

Two dorsal fins present, both these and the anal with an anterior 
spine. Clavicular bones absent. 

This family is represented only by the type genus. 

Genus IS CHN ACANTHUS, Powrie. 

[Quart. Journ. Geol. Soc. vol. xx. 1864, p. 419.] 

Syn. Ictinocephalus, D. Page, Rep. Brit. Assoc. 1858, Trans. Sect. 
p. 104 (undefined). 

Body fusiform, laterally compressed. Dentition prominent, con- 
sisting of few large conical teeth, the interspaces between these 
teeth being occupied by a close series of minute cusps, all apparently 
in firm connection with a membrane-bone in both jaws. ISTo median 
pair of spines attached to the pectoral arch between the pectoral 
fin-spines. 



TSCHNAC ANTHTD-S!. 21 

This genus was withdrawn by J. Powrie in 1870 l , the type 
species being assigned to Diplacanthus ; but it has lately been once 
more adopted by R. H. Traquair 2 . 

Ischnacanthus gracilis (Egerton). 
[Plate I. fig. 8.] 

1859. Ictinocephalus granulatus, D. Page, Rep. Brit. Assoc. 1858, Trans. 

Sect. p. 105 (name only). 
1861. Diplacanthus gracilis, Sir P. Egerton, Figs. & Descrips. Brit. 

Organic Remains (Mem. Geol. Surv.), dec. x. p. 69, pi. ix. 
1864. Ischnacanthus gracilis, J. Powrie, Quart. Journ. Geol. Soc. vol. 

xx. p. 419. 
1870. Diplacanthus gracilis, J. Powrie, Trans. Edinb. Geol. Soc. vol. i. 

p. 290, pi. x. fig. 2. 
1888. Ischnacanthus gracilis, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 512. 

Type. Nearly complete fish. 

The type species, attaining a maximum length of about 0-12-0-16. 
Body slender and elongated, the greatest depth being contained 
about five times in the total length. Fin-spines slender, coarsely 
striated longitudinally. Pectoral fin-spines gently arched ; no pair 
of free spines between these and the pelvic fins ; pelvic fin-spines 
about two thirds as large as the pectoral, and placed midway 
between these and the anal. Dorsal spines nearly equal in size, or 
the second slightly the larger ; first dorsal spine placed well behind 
the pectorals, second dorsal immediately behind the anal, which is 
somewhat smaller. Scales smooth. Large dental crowns robust and 
smooth. 

Form. Sf Log. Lower Old Red Sandstone : Forfarshire. 

All the following specimens were obtained from Turin Hill, near 
Forfar :— 

38517. Small example. Purchased, 1864. 

38598-99. Nearly complete fish, displaying dentition ; and an im- 
perfect large specimen, probably exceeding 0*16 in length. 
Presented by James Powrie, Esq., 1864. 

41363-64. Trunk with complete tail, and an imperfect crushed 
specimen. Purchased, 1869. 

46303. Imperfect trunk and tail, in counterpart, of an individual 
probably 0*16 in total length. Purchased, 1875. 

1 Trans. Edinb. Geol. Soc. vol. i. (1870) p. 289. 

2 Geol. Mag. [3] vol. v. (1888) p. 512. 



22 ACANTHODII. 

46305, 46305 a. Four specimens, two being destitute of the tail ; 
also an imperfect left mandibular ramus with portions of 
the dentition. Purchased, 1875. 

P. 132-6, P. 141-2, P. 144-8. Twelve specimens, the first preserved 
in counterpart and shown, of the natural size, in PL I. 
fig. 8. This specimen appears to exhibit the precise out- 
line of the fish, without distortion, and all the fin-spines 
are preserved in their natural positions. Two large teeth 
remain in the upper jaw, but the bones and cartilages of 
the head are obscure. A series of short, vertically elon- 
gated impressions in the anterior portion of the trunk 
have the appearance of neural arches ; though, if so, the 
head has been somewhat displaced by crushing, for a few 
of these impressions occur far forwards. The character- 
istic form of the basal cartilage of one pectoral fin is indis- 
tinctly shown. Portions of the membrane of the pelvic 
and anal fins are exhibited, and the caudal is apparently 
complete. Purchased, 1880. 

P. 1344. Two small specimens, and one measuring not less than 
0-15 in length. Egerton Coll. 

The following specimen is not certainly determinable, but appears 
to pertain to a large individual of this species : — 

P. 131. Caudal region and hinder portion of the abdominal region 
of an Acanthodian fish, the specimen preserved in counter- 
part and measuring 0-13 in length ; Lower Old Eed Sand- 
stone, Turin Hill, near Forfar. Remains of the pectoral 
spines show that these were of moderate size, slender, 
arched, and finely ribbed. One dorsal spine (presumably 
the second) is situated slightly behind the anal, and the 
caudal fin is very robust. The scales are minute, smooth, 
and faintly hollowed. Purchased, 1880. 

Family DIPLACANTHID./E. 

Two dorsal fins present, both these and the anal with an anterior 
spine. Pectoral arch with clavicular bones. 

Synopsis of Genera. 

A. Paired spines between pectoral and pelvic 
fins insignificant or absent. 
Teeth minute or absent; median pair of 

spines between pectorals Diphcanthus (p. 23). 



DIPLACANTHID^. 23 

B. Paired spines between pectoral and pelvic fins 
well developed. 
Anterior dorsal fin-spine not exceeding the 

posterior in length Climatius (p. 28). 

Anterior dorsal fin-spine much exceeding the 

jrior in length Parexus (p. 33). 



Genus DIPLACANTHUS, Agassiz. 
[Poiss. Foss. V. G. E. 1844, pp. 34, 40.] 
Syn. Rhadinacanthus, R. H. Traqnair, Geol. Mag. [3] vol. v. 1888, p. 512. 

Body fusiform, probably not much laterally compressed. Teeth 
minute or absent ; orbit with ring of four circumorbital dermal 
plates. Pectoral fins large, and a median pair of stout spines fixed 
between these to the basal pterygia ; a pair of free spines situated 
ventrally between the pectoral and pelvic fins. 

The pectoral fins in this genus are somewhat difficult of interpre- 
tation, but the accompanying woodcut (fig. 3) seems to represent 

Fig. 3. 




Pectoral arch and fins of Diplacanthus striatus, Ag.—b, basal cartilage ; 
cl. clavicle ; i.cl, infraclavicle ; m, median spine ; s, fin-spine. 

the arrangement of the spines and pectoral arch in the type species. 
As is usually the case in crushed specimens, the fin-spines are exhi- 
bited from the dorsal aspect, and the ascending limb of the pectoral 
arch is bent forwards and exposed from the inner side. The greater 
portion of the pectoral arch consists of a pair of vertically elongated 
elements (cl), each having a straight rod-like axis, filled with calcite 
in the fossil, and thus originally either hollow or occupied by uncal- 
cified tissue ; behind this axis there is a thin laminar expansion 
of bone, diminishing upwards, and apparently extending downwards 
and inwards to form an inferior limb. The pair of large bones does 
not meet in the median line below, but is separated by a much 
smaller pair of bony laminae (i.cl.), united in a finely dentated 



24 ACANIHODII. 

mesial suture. Both these elements have precisely the appearance 
of membrane-hones ; and in some genera (e. g. Parexus, No. P. 130, 
p. 35) the conformation of the scales in the pectoral region so inti- 
mately depends upon their form and position, that they are evidently 
of a superficial character. We therefore venture to determine them 
as clavicles and infraclavicles. The truncated extremity of the 
pectoral fin-spine (s.) directly abuts against the angle of the 
supposed clavicle, while that of the mesial spine (m.) is chiefly 
apposed to the same element, though in part also to the infraclavicle. 
The axes of these two spines are inclined towards one another, and 
at their proximal extremity they are firmly united by a triangular 
mass of hard tissue (6), which is probably to be regarded as the 
basipterygium or basal cartilage. 



Diplacanthus striatus, Agassiz. 

1841. " Ichthyolite," H. Miller, Old Red Sandstone, pi. viii. fig. 2. 

1842. Diplocanthus crassisimus, P. Duff, Geol. Moray, p. 71, pi. x. fig. 2. 
1844. Diplacanthus striatus, L. Agassiz, Poiss. Foss. V. G. R. pp. 34, 

41, pi. xiv. figs. 1-5. 
1844. Diplacanthus striatulus, L. Agassiz, ibid. pp. 34, 42, pi. xiii. figs. 

3, 4. [Forres Museum and British Museum.] 
1844. Diplacanthus crassispinus, L. Agassiz, ibid. pp. 34, 43, pi. xiii. 

figs. 1, 2, pi. xiv. figs. 6, 7. [British Museum, in part.] 
1848. Diplacanthus gibbus, F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. ii. 

p. 301. [Woodwardiau Museum, Cambridge.] 
1855. Diplacanthus gibbus, F. M'Coy, Brit. Palaeoz. Foss. p. 584, pi. ii b. 

fig. 4. 
1888. Diplacanthus striatus, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 512. 

Type. Nearly complete fishes ; Edinburgh Museum (in part). 

The type species, usually attaining a length of # 07-0-l. Body 
robust, but elongated, the greatest depth being contained about 
four and a half times in the total length. Fin-spines very stout, 
coarsely striated longitudinally. Pectoral fin-spines much arched 
and sharply pointed, the median spines relatively large ; pelvic fin- 
spines scarcely half as large as the pectoral. First dorsal spine 
much stouter and larger than the second, placed almost immediately 
above the pectoral arch; second dorsal spine opposed to the anal 
and somewhat larger than the latter. Scales smooth. 

Form, fy Log. Lower Old Red Sandstone : Cromarty, Banffshire, 
Nairnshire, Ross-shire, and Orkney Isles. 

19073-74. Imperfect specimen, in counterpart ; Cromarty. 

Purchased, 1S45. 



DIPLACANTHIDiE. 25 

19406, 19802. One specimen displaying the dorsal and anal fin- 
spines, and four more crushed, imperfect fishes ; Cromarty. 

Pur chased , 1845. 

P. 1360, P. 3260. Pish displaying most of the fin-spines, and a 
more imperfect specimen in counterpart ; Cromarty. 

Egerton and EnnisMllen Colls. 

P. 4047. Specimen in counterpart, showing fin-spines and second 
dorsal fin ; Gamrie. The median pair of pectoral spines 
is well shown, and that of the left side is seen to be con- 
nected by some intermediate tissue at its base with the 
outer pectoral spine. Purchased, 1883. 

41900. Imperfectly preserved fish, lateral aspect, wanting paired 
spines ; Gamrie. Purchased, 1870. 

P. 543. One of the type specimens of D. striatidus, figured by 
Agassiz, op. cit. pi. xiii. fig. 4 ; Lethen Bar. Egerton Coll. 

P. 1357 a, P. 1364. Two imperfect similar fishes, one ventral, and the 
other lateral aspect; Tynet Burn. The first specimen 
exhibits an inner view of the pectoral arch with displaced 
infraclavicles. Egerton Coll. 

P. 1366. Pish wanting the head and the extremity of the tail, 
lateral aspect ; Tynet Burn. There are distinct indications 
of a double series of well-spaced endoskeletal supports in 
the front part of the lower lobe of the caudal fin. 

Egerton Coll. 

35053. A very small specimen, ventral and lateral aspect ; Tynet 
Burn. Purchased, 1860. 

35987, 36066. Imperfect remains of two fishes ; Tynet Burn. 

Purchased, 1861. 

36582. Specimen displaying the paired fin-spines from beneath; 
Tynet Burn. The element connecting the pectoral spine 
of each side with its adjoining median spine seems to be a 
superficially calcified cartilage. The interdigitating infra- 
clavicles are seen in position. Purchased, 1862. 

43275. Small specimen, ventral aspect ; Tynet Burn. 

Purchased, 1871. 

P. 1173. Imperfect specimen, lateral aspect ; Edderton, near Tain. 

Egerton Coll. 

P. 177. Imperfect specimen: Orkney. Purchased, 1881. 



26 ACANTHODII. 

43018. Specimen assigned to D. crassispinus by Agassiz, op. tit. 
pi. xiii. fig. 2 ; Orkney. Purchased, 1871. 

36327. Imperfect specimen, showing some of the spines ; Orkney. 

Purchased, 1862. 

39190-91. Two very indistinctly preserved specimens; Skaill, 
Orkney. BowerbanJc Coll, 

41843-44. Two similar fossils : Orkney. Purchased, 1869. 

P. 1357-9. Seven specimens, very imperfect ; Belyacreugh and 
Ramna Gio, Orkney. Egerton Coll. 

P. 3261. Trunk with caudal extremity; Eelyacreugh. 

Ennishillen Coll. 



Diplacanthus longispinus, Agassiz. 

[Plate III. fig. 1.] 

1841. "Ichthyolite," H. Miller, Old Red Sandstone, pi. viii. fig. 1. 
1844. Diplacanthus longispinus, L. Agassiz, Poiss. Foss. V. G. R. pp. 

34, 42, pi. xiii. fig. 5, pi. xiv. figs. 8, 9. 
1848. Diplacanthus perarmatus, F. M'Coy, Ann. Mag. Nat. Hist. [2] 

vol. ii. p. 301. [Woodwardian Museum, Cambridge.] 
1855. Diplacanthus perarmatus, F. M'Coy, Brit. Palaeoz. Foss. p. 585, 

pi. iiB. fig. 3. 
1888. Rhadinacanthus longispinus, R. H. Traquair, Geol. Mag. [3] 

vol. y. p. 512. 

Type. Nearly complete fish ; Forres Museum. 

A large species, attaining a maximum length of about 0*22. 
Body robust, but elongated, the greatest depth being contained 
about four and a half times in the total length. Fin-spines much 
elongated, with at least one longitudinal sulcus parallel to the ante- 
rior margin. Pectoral fin-spines about one third larger than the 
pelvic pair, and the median pectorals relatively small, well separated 
from the ordinary pectorals ; pelvic fins situated much nearer to the 
anal than to the pectorals. Dorsal fin-spines very large and elon- 
gated, the first smaller than the second, placed slightly behind the 
pectoral arch ; second dorsal opposed to the anal and much larger 
than the latter. Scales marked with prominent radiating furrows 
and ridges. 

This species is regarded as the type of a distinct genus, Rhadina- 
canthus, by Traquair, on the assumption that median pectoral spines 
are absent. A specimen recorded below (No. P. 4041), however, 
proves that the spines in question occur in their usual place ; and 



DIPLACANTniD^E. - / 

there is thus no justification for the proposed change in nomen- 
clature. 

Fowl <$f Loc. Lower Old Red Sandstone : Nairnshire, Banffshire, 
Cromarty, and Orkney Isles. 

49184. Specimen showing displaced dorsal spines, the anal, and 
portions of the pectoral arch, in counterpart ; Lethen Bar. 

Purchased, 1878. 

P. 1362. Fragment, with first dorsal fin ; Lethen Bar. 

Egerton Coll. 

P. 5076. Imperfect specimen, in counterpart, with pectoral, pelvic, 
and anal spines, and a fragment of the second dorsal ; 
Lethen Bar. Presented by J. E. Lee, Esq., 1885. 

P. 1361. Nodule with imperfect remains of a fish ; Gamrie. 

Egerton Coll, 

P. 4040. Large, well-preserved specimen, in counterpart, lateral 
aspect ; Gamrie. Purchased, 1883. 

P. 4041. Smaller fish, in counterpart, shown from the ventral and 
lateral aspects, and displaying part of the pectoral arch 
with the median pectoral spines ; Gamrie. The specimen 
is represented, of the natural size, in PI. III. fig. 1, and 
the various parts indicated by the lettering. It is of 
especial interest as exhibiting very distinctly the lower 
expanded portion of the right side of the pectoral arch, 
with a short, stout, straight, acute spine, directed back- 
wards from its median end. Unfortunately, however, no 
precise details of the basipterygium of the pectoral fin can 
be observed. Purchased, 1883. 

P. 5075. Nearly complete fish, lateral aspect, in half of nodule ; 
Gamrie. Presented by J. E. Lee, Esq., 1885. 

P. 6188. Trunk with fins and part of head, in counterpart ; Gamrie. 

Purchased, 1890. 

P. 176. Very imperfectly preserved specimen in flagstone; Orkney. 

Purchased, 1881. 

P. 1369. Similar fossil ; Orkney. Egerton Coll. 



28 



ACANTTTODII. 



Genus CLIMATIUS, Agassiz. 

[Poiss. Foss. V. G. R. 1845, p. 119.] 

Syn. Br achy acanthus, Sir P. Egerton, Rep. Brit. Assoc. 1859 (1860), 
Trans. Sect. p. 116. 
Euthacanthus, J. Powrie, Quart. Jonrn. Geol. Soc. vol. xx. 1864, 
p. 425. 

Body fusiform, laterally compressed. Teeth minute or absent. 
Fin-spines extremely robust, marked with coarse longitudinal 
ridges, sometimes with posterior denticles; first dorsal spine not 
excessively elongated ; several pairs of free spines on the ventral 
aspect between the paired fins. 

A detached fin-spine only was known to Agassiz, and the precise 
definition of the genus was first rendered possible by Egerton's 
discovery of C. scutiger. 

Climatius reticulatus, Agassiz. 

1845. Climatius reticulatus, L. Agassiz, Poiss. Foss. V. G. R. p. 120, 

pi. xxxiii. fig. 26. 
1861. Climatius reticulatus, Sir P. Egerton, Figs. & Descrips. Brit. 

Organic Remains (Mem. Geol. Surv.), dec. x. p. 68, pi. viii. figs. 

11-13. 
1864. Climatius reticulatus, J. Powrie, Quart. Journ. Geol. Soc. vol. xx. 

p. 421. 
1870. Climatius reticulatus, J. Powrie, Trans. Edinb. Geol. Soc. vol. i. 

p. 295, pi. xiii. fig. 10. 

Type. Detached fin-spine. 

The type species, attaining a maximum length of about 0-2. 
Body elongated, the greatest depth being contained probably more 
than five times in the total length ; head and branchial apparatus 
occupying one fourth of the total length. Spines all short and broad, 
the longitudinal ridges being more or less tuberculated, and the 
transverse lines of growth at the base usually prominent. Pectoral 
fin-spines the largest and most elongated, considerably arched, 
without posterior denticles ; four pairs of very short and broad, 
small, intermediate, ventral spines, of which the hindermost pair is 
the largest ; pelvic fin-spines less than half as large as the pectoral. 
First dorsal spine shorter, broader, and more curved than the second, 
situated midway between the pectoral and pelvic pairs ; second 
dorsal spine comparatively straight, slender, and pointed, similar to 
the anal, and either directly opposed to the latter or immediately in 
advance of it. Scales relatively large, smooth, or tuberculated. 

Form. § Loc. Lower Old Red Sandstone : Forfarshire. 



DIPLACAXTHlDiE. 21) 

38596. Imperfect fish, showing large tuberculated dermal scales 
upon the head and portions of most of the spines ; Turin 
Hill, Forfar. Presented by James Powrie, Esq., 1864. 

P. 137. Imperfect fish, displaying most of the spines ; Turin Hill. 

Purchased, 1880. 

P. 138-9. Fragment of the head and anterior portion of the trunk 
of a small fish, preserved in counterpart ; also the trunk 
with pectoral arch and most of the spines of a similar 
small individual ; Turin Hill. Purchased, 1880. 

P. 1343, P. 1343 a. Imperfectly preserved large fish, about 0-2 in 
total length, displaying variations in squamation ; also a 
small individual exhibiting more of the spines ; Turin Hill. 

Egerton Coll. 

P. 584. Counterpart of imperfect second dorsal fin-spine, figured by 
Egerton, loc. cit. fig. 12 ; Farnell. Egerton Coll. 

P. 1343 b. Three fragmentary impressions of spines ; Farnell. 

Egerton Coll. 

Climatius scutiger, Egerton. 

1860. Brachyacanthus scutiger, Sir P. Egerton, Rep. Brit. Assoc. 1859, 
Trans. Sect. p. 116. 

1861. Climatius scutiger, Sir P. Egerton, Figs. & Descrips. Brit. Organic 
Remains (Mem, Geol. Surv.), dec. x. p. 65, pi. viii. figs. 1-10. 

1864. Climatius scutiger, J. Powrie, Quart. Journ. Geol. Soc. vol. xx. 

p. 423. 
1870. Climatius scutiger, J. Powrie, Trans. Edinb. Geol. Soc. vol. i. 

p. 296, pi. xiv. figs. 12, 13. 

Type. Nearly complete fishes ; British Museum (in part). 

A very small species, attaining a maximum length of about 0*06. 
Body elongated, the greatest depth being contained probably more 
than five times in the total length ; head and branchial apparatus 
occupying one fifth of the total length. Spines all short and broad, 
the longitudinal ridges being sometimes tuberculated. Pectoral fin- 
spines stout and slightly arched, about equal in size to the first 
dorsal ; four pairs of very short and broad, small, intermediate 
ventral spines ; pelvic fin-spines about half as large as the pectoral. 
First dorsal spine shorter, broader, and more curved than the second, 
situated midway between the pectoral and pelvic pairs ; second 
dorsal spine comparatively straight, slender, and pointed, slightly 
more remote and much larger than the anal. Scales mostly small, 



30 ACANTHODII. 

smooth or externally sculptured ; a single series of somewhat larger 
ridge-scales between the occiput and the first dorsal fin. 
Form, fy Loc. Lower Old Red Sandstone : Forfarshire. 

35907-8. Two fine specimens, the second measuring not more than 
0-035 in length and exhibiting the extremely attenuated 
tail ; Farnell. Presented by James Powrie, Esq., 1861. 

P. 561-2. Two of the type specimens, figured by Egerton, he. cit. 
(1861), pi. viii. figs. 2, 3 ; Farnell. Egerton Coll 

P. 1341. Fish wanting the extremity of the caudal region ; also a 
fragment of the head and abdominal region ; Farnell. 

Egerton Coll. 

P. 3263. Two small specimens : Farnell. Enniskillen Coll. 

Climatius uncinatus, Powrie. 

1864. Climatius uncinatus, J. Powrie (ex Egerton, MS.), Quart. Journ. 

Geol. Soc. vol. xx. p. 422. 
1870. Climatius uncinatus, J. Powrie, Trans. Edinb. Geol. Soc. vol. i. 

p. 296, pi. xiv. fig. 11. 

Type. Fish ; collection of James Powrie, Esq., Reswallie. 

A small species, attaining a maximum length of about 0*1. Body 
elongated ; head and branchial apparatus occupying about one fifth 
of the total length. Spines broad, but elongated. Pectoral fin-spines 
the largest, considerably arched, with large posterior denticles ; 
four pairs of short and broad, small, intermediate ventral spines ; 
pelvic fin-spines about half as large as the pectoral. First dorsal 
spine straight, almost identical with the second ; the latter some- 
what larger than the anal and placed slightly in advance of this. 

Form. 8f Loc. Lower Old Red Sandstone : Forfarshire. 

P. 1342. Imperfect specimen, showing portions of denticulated 
pectoral spines ; Turin Hill, near Forfar. Egerton Coll. 

Climatius macnicoli (Powrie). 

1864. Euthaeanthus menicoli, J. Powrie, Quart. Journ. Geol. Soc. vol. xx. 

p. 425, pi. xx. fig. 2. 
1870. Euthaeanthus m'mcoli, J. Powrie, Trans. Edinb. Geol. Soc. vol. i. 

p. 290, pi. xi. fig. 3. 
1890. Climatius macnicoli, Woodward & Sherborn, Cat. Brit. Foss. 

Yertebrata, p. 36. 

Type. Complete fish ; collection of James Powrie, Esq., Beswallie. 
A species of large size, about 0-17 in maximum length. Body 



DIPIACANTHIDiE. 



31 



elongated, the greatest depth being contained more than five times 
in the total length. Spines comparatively straight and narrower 
than in the type species ; longitudinal ridges usually smooth. 
Pectoral fin-spines straight, scarcely larger than the first dorsal ; 
five pairs of intermediate ventral spines, separated by a distinct 
interval from the pelvic fin-spines ; the latter at least two thirds as 
long as the pectoral pair. First dorsal spine shorter and stouter 
than the second, situated midway between the pectoral and pelvic 
pairs : second dorsal spine very slightly in advance of the anal, 
about equal to this in size. Scales smooth. 

This is the type species of EutTiacanthus, Powrie. 

Form. <$f Log. Lower Old Eed Sandstone : Forfarshire. 

P. 1337. Imperfectly preserved trunk, wanting the head and tail, 
but exhibiting the situation and proportions of the spines ; 
Forfar. Egerton Coll. 

Climatius grandis (Powrie). 

1870. Euthacanthus grandis, J. Powrie, Trans. Edinb. Greol. Soc. vol. i. 
p. 292, pi. xii. fig. 6. 

Type. Fragments of fish ; collection of James Powrie, Esq., Res- 
wallie. 

A very large species, attaining a maximum length of not less 
than 0*6 (according to Powrie). Body much elongated. Spines 
comparatively straight and narrower than in the type species ; lon- 
gitudinal ridges usually smooth. Pectoral fin-spines straight, pro- 
bably about equal to the first dorsal in size ; not less than four pairs 
of intermediate ventral spines, separated by a distinct interval from 
the pelvic fin- spines ; the latter at least two thirds as long as the 
pectoral pair. First dorsal spine smaller than the second, situated 
somewhat nearer to the pectoral than the pelvic pair ; second dorsal 
spine slightly in advance of the anal, and much larger than the 
latter. Scales of the flank in the abdominal region ornamented 
with a few short horizontal striae in the anterior half ; other scales 
mostly smooth. 

Form. <$f Log. Lower Old Red Sandstone : Forfarshire. 

38597. Crushed trunk of small individual, wanting head and 
extremity of the tail, showing four pairs of intermediate 
ventral spines and portions of the pelvic, anal, and dorsal 
fin-spines ; Turin Hill, Forfar. 

Presented by James Poivrie, Esq., 1864. 



32 UWNTH0D11. 

P. 129. Small individual, wanting the head, preserved in counter- 
part ; Turin Hill. Portions of all the spines are shown. 

Purchased, 1881. 

P. 128. Hinder portion of abdominal region and caudal region of a 
fish measuring 0*18 from the second dorsal spine to the 
extremity of the tail, preserved in counterpart ; Turin Hill. 
In addition to the scales this specimen exhibits the pelvic, 
second dorsal, and fragmentary anal spines. 

Purchased, 1880. 

Climatius gracilis (Powrie). 

1870. Euthacanthus gracilis, J. Powrie, Trans. Edinb. Geol. Soc. vol. i. 
p. 291, pi. xi. fig. 4. 

Type. Fish wanting head and anterior half of abdominal region ; 
collection of James Powrie, Esq., Eeswallie. 

A species about 0-2 in length. Body much elongated ; spines 
comparatively straight. Eour or five pairs of intermediate ventral 
spines, separated by a distinct interval from the pelvic fin-spines ; 
the latter more than half as long as the anal spine. First dorsal 
spine shorter than the second, about midway between the pectoral 
and pelvic pairs ; second dorsal spine much larger than the anal, 
well in advance of the latter, almost opposed to the pelvic spines. 
Lateral line with double series of enlarged scales. {Powrie.) 

Form. Sf Log. Lower Old Red Sandstone : Farnell, Forfarshire. 

Not represented in the Collection. 

The so-called Euthacanthus elegans, Powrie (torn. cit. 1870, p. 292, 
pi. xii. fig. 5), is founded upon an imperfect impression of a fish from 
Farnell, only differing from Climatius gracilis in the proportions of 
some of the spines, which may be imperfectly shown. Another 
species, Euthacanthus curtus, Powrie (ibid. p. 293, pi. xii. fig. 7), 
from Turin Hill and Farnell, does not appear to belong to this 
genus, and is doubtfully referred to Diplacanthus by Woodward and 
Sherborn, Cat. Brit. Foss. Yertebrata (1890), p. 65. The type speci- 
mens are in the collection of James Powrie, Esq. 

Climatius (?) ornatus (Agassiz). 

1837. Ctenacanthus ornatus, L. Agassiz, Poiss. Foss. vol. iii. p. 12, 

pi. ii. fig. 1. 
1845. Ctenacanthus ornatus, L. Agassiz, Poiss. Foss. V. G. R. pp. Ill, 

119. 
1857. u Ichthyodomlites," Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. xiii. p. 288, pi. x. figs. 5, 7. 



DlPLACANTHlD-«. 



33 



Type. Fragment of spine. 

An undefined species known only by fragments of fin-spines 
more closely resembling those of CUmatius than of any other genus. 
The longitudinal ridges upon the spine are notched, the intervals 
being very short immediately above the base, and at least twice as 
long as these throughout the more distal portion. 

Form. <$f Loc. Lower Old Red Sandstone (Passage Beds) : Here- 
fordshire and Worcestershire. 

P. 5092. Two imperfect spines ; Tin Mill, Downton, near Ludlow. 

Presented by J. E. Lee, Esq., 1885. 

Climatius (?) latispinosus (Whiteaves). 

1881. Ctenacanthus latispinosus, J. F. Whiteaves, Canadian Naturalist, 

n. s. vol. x. p. 99. 
1889. Ctenacanthus latispinosus, J. F. Whiteaves, Trans. Roy. Soc. 

Canada, vol. vi. sect. iv. p. 95, pi. x. fig. 3. 
1889. Climatius latispinosus, A. S. Woodward, Ann. Mag. Nat. Hist. 

[6] vol. iv. p. 183. 

Type. Detached fin-spines ; Geological Survey of Canada, Ottawa. 

An undefined species known only by detached fin-spines, which 
attain a relatively large size. The spines are broad, nearly 
straight, with finely tuberculated ridges and prominent posterior 
denticles. 

Form. Sf Loc. Lower Devonian : Campbellton, New Brunswick. 

P. 6223. Imperfect spine. Presented by the Director of the Geological 

Survey of Canada, 1890. 

A doubtful spine is also described as follows : — 

Climatius aculeatus, E. von Eichwald, Leth. Rossica, vol. i. (1860), 
p. 1602, pi. lvii. fig. 20. — Old Red Sandstone ; Slawjanka, 
near Pawlowsk, St. Petersburg. [University of St. Peters- 
burg.] 

Genus PAREXUS, Agassiz. 
[Poiss. Foss. Y. G. R. 1845, p. 120.] 

Body deeply fusiform, laterally compressed ; caudal fin large and 
powerful. Teeth minute or absent. Fin-spines robust, marked with 
coarse longitudinal ridges ; first dorsal spine enormously developed, 
with large posterior denticles ; several pairs of free spines on the 
ventral aspect between the paired fins. 

The first dorsal fin-spine only was known to Agassiz, and the 
genus thus remained imperfectly defined until 1864, when Powrie 
discovered a complete example of the type species. 

PART II. d 



34 ACANTHODII. 

Parexus incurvus, Agassiz. 

1845. Parexus incurvus, L. Agassiz, Poiss. Foss. V. G. R. p. 120, pi. 

xxxiii. figs. 20, 27. 
1864. Parexus incurvus, J. Powrie, Quart. Journ. Geol. Soc. vol. xx. 

p. 424, pi. xx. fig. 1. 
1S70. Parexus incurvus, J. Powrie, Trans. Edinb. Geol. Soc. vol. i. 

p. 293, pi. xii. fig. 8. 

Type. Imperfect first dorsal fin-spine. 

The type species, attaining a maximum length of about 0*16, but 
usually much smaller ; head occupying one fourth of the total length. 
Fin -spines with crenulated ridges. Pectoral fin-spines short, stout, 
and curved ; not less than four pairs of short and broad, small, 
intermediate ventral spines ; pelvic fin-spines about two thirds as 
long as the pectorals, much less robust. First dorsal spine straight 
or only slightly curved, at least half as long as the complete fish, 
situated immediately above the pectoral arch, with few, widely 
spaced, upwardly directed, posterior denticles ; second dorsal spine 
about one third as long as the first, placed immediately in advance 
of the anal, which it somewhat exceeds in size. Scales externally 
tuberculated. 

In this species the first dorsal fin is shown to be very small in 
proportion to the size of the spine, while the second dorsal fin 
extends to the apex of its spine. 

Form. <$)- Log. Lower Old Eed Sandstone : Forfarshire. 

38593. Contorted fish, showing portions of all the fin-spines and the 
second dorsal and caudal fins ; Turin Hill, near Forfar. 

Presented by James Powrie, Esq., 1864. 

P. 127. Imperfect small fish, wanting the caudal fin ; Turin Hill. 
The ornamentation and posterior denticles of .the first 
dorsal spine are well exhibited. Purchased, 1880. 

P. 1338. A specimen nearly similar to the last, and a more imper- 
fectly preserved fish, displaying the dermal scales and 
plates of the head ; Turin Hill. Egerton Coll. 

P. 1339-40. Three imperfect impressions of the first dorsal spine; 
Farnell. Egerton Coll. 

Parexus falcatus, Powrie. 

1870. Parexus falcatus, J . Powrie, Trans. Edinb. Geol. Soc. vol. i. 
p. 294, pi. xiii. fig. 9. 

Type. Well-preserved fish ; collection of James Powrie, Esq., 
Reswallie. 



DIPLACANTHID^. 



35 



A species of larger size than P. incurvus ; head very large, occu- 
pying one third of the total length. Pectoral fin-spines short, stout, 
and curved ; four pairs of short and broad, small, intermediate 
ventral spines ; pelvic fin-spines about two thirds as long as the 
pectorals, much less robust. First dorsal spine very stout and much 
curved, with few, widely spaced, posterior denticles, about one third 
as long as the complete fish and situated immediately above the 
pectoral arch ; second dorsal spine about one half as long as the 
first, placed immediately in advance of the anal, which it somewhat 
exceeds in size. Scales externally tuberculated. 
• Form, fy Log. Lower Old Red Sandstone : Forfarshire. 

P. 130. Imperfect fish, wanting the head, the extremity of the tail, 
and the first dorsal fin-spine ; Turin Hill, near Forfar. 
The abdominal region is shown from the ventral, and the 
caudal region from the lateral aspect. The pectoral arch 

Fig. 4. 




Pectoral fin and half of pectoral arch of Parexus falcatus, Powrie. — b, basal 
cartilage ; cl, clavicle ; s, spine. 

and spines are shown from beneath, and the elements of 
the left side are represented in a somewhat diagrammatic 
manner in the accompanying woodcut. The pectoral arch 
consists of a pair of thin, triangular or sickle-shaped 
elements (fig. 4, cZ), meeting in the middle line, and the 
inferior limb apparently as large as the ascending limb ; 
as shown in the figure, the latter is crushed so as to be 
directed backwards. The squamation on the ventral aspect 
between the pectoral fins is much enlarged and .covers an 
anteriorly narrowing triangular area to the point of 
meeting of the two halves of the pectoral arch in the 
median line ; and this arrangement of the scales in direct 
relation to the latter suggests that the elements preserved 
fall within the category of membrane-bones (clavicles). 

d2 



36 CHIM3GR0IDEI. 

The basal cartilage (b) of the fin is evidently almost as 
long as the upper part of the supposed clavicle, with a very 
broad, triangular, distal extremity, meeting the obliquely 
truncated, attached end of the pectoral spine (s), and ter- 
minating in a very slender, rounded, proximal half. The 
fin-membranes are shown both in connection with this 
and all the other fin-spines ; and there are four pairs of 
broad, intermediate ventral spines, increasing in size 
posteriorly. Purchased, 1880. 



Subclass II. HOLOCEPHALI. 

Skeleton cartilaginous, membrane-bones absent. Mandibular sus- 
pensorium and upper jaw fused with the cranium. Exoskeleton, 
when present, structurally identical with the teeth. In the living 
forms — optic nerves not decussating, bulbus arteriosus of the heart 
with three series of valves, intestine with a spiral valve, and ovaries 
with few large ova. 



Order CHIM.EROIDEL 

Notochord persistent or partially constricted, the calcifications in 
the sheath, when present, consisting of slender rings more numerous 
than the neural and haemal arches. Pectoral fins shortened, without 
segmented axis ; pelvic fins produced into a pair of claspers in the 
male. In the living forms — a fold of skin covering the gill-clefts, 
and leaving a single external opening to the gill-cavity. 

In all the known families of Chimseroids, the dentition consists 
of few large plates of vascular dentine, of which certain areas 
(" tritors ") are specially hardened by the deposition of calcareous 
salts within and around groups of medullary canals, which rise at 
right angles to the functional surface. In most cases there is a 
single pair of such plates in the lower jaw, meeting at the sym- 
physis, while two pairs are arranged to oppose these above. As a 
whole, the dentition thus closely resembles that of the typical 
Dipnoi (as has often been pointed out) ; and the upper teeth may 
be provisionally named palatine and vomerine until further dis- 
coveries shall have revealed their precise homologies. The struc- 
tures are sometimes described as "jaws," and regarded as dentaries, 
maxilla?, and premaxillae, but the presence of a permanent pulp 



PTYCTODONTID-E. 37 

under each tooth * is conclusive proof of their bearing no relation to 
the familiar membrane-bones thus named in higher fishes. 

Synopsis of Families. 

I. [Imperfectly defined. Spines unknown.] 

One pair of dental plates above and 

below PTYCTODONTID.E (p. 37). 

II. Dorsal fin-spines absent. Rostral spine 
in male. 

Trunk depressed, snout elongated. Two 
pairs of dental plates above, one pair 
below , Squalorahd^: (p. 40). 

III. Spine in front of anterior dorsal fin. 
Rostral spine in male. 

Few dermal plates on head. Two pairs of 

dental plates above, one pair and an 

anterior azygous tooth below Myriacanthid^; (p. 43). 

No dermal plates. Two pairs of dental 

plates above, one pair below Chim^erid^: (p. 52). 



Family PTYCTODONTID.E. 

A family at present indefinable, of doubtful ordinal position, 
known only by remains of the dentition. A single pair of large, 
laterally compressed, dental plates in each jaw, meeting at the 
symphysis and with few tritoral areas. 

The genera of this family have not hitherto been defined, even so 
far as existing materials will permit. There are as yet no examples 
of the teeth in the collection of the British Museum ; but an exami- 
nation of a large number of Russian specimens in St. Petersburg, 
American specimens in New York, recently discovered examples 
from Canada in the Geological Survey Collection at Ottawa, and 
several undescribed forms from the Eifel Devonian in the Museum 
of Comparative Zoology, Cambridge (Mass.), has suggested to the 
writer the following provisional arrangement. 

Synopsis of Genera. 

I. Symphysial surface narrow; tritors more or 
less laminated. 
Oral surface triturating, the tritors being 
well differentiated and consisting of 
hard, punctate, superimposed laminas, 
arranged obliquely to the functional 
surface Ptyctodus, Pander. 

1 K. Owen, Odontography, p. 65. 



CHIMJiROlDEI. 



II. 



Oral surface forming a narrow oblique knife- 
edge, with no differentiated tritors, but 
having a lamellar-punctate structure 

within the outer wall Rkynchodus, Newberry. 

Syniphysial surface relatively very broad; 

tritors punctate. 
Oral surface triturating, with a single inde- 
finite tritoral area Pakeomylus, gen. no v. 



Genus PTYCTODUS, Pander. 

[Ctenodipt. devon. Syst. 1858, p. 48.] 

Syn. Aulacosteus, E. von Eichwald, Geognosy of Russia (in Russian), 
1846 (according to Leth. Rossica, vol. i. 1860, p. 1548). 
Rinodus, Newberry & Worthen, Pal. Illinois, vol. ii. 1866, p. 106. 

In this genus the tritoral areas are so much harder than the rest 
of the tooth that they are often preserved in a rolled state after the 
removal of the surrounding tissue. Such is the condition of all 
specimens hitherto described, except the originals of Pander's pi. viii. 
figs. 10, 12, which exhibit the symphysial region. Specimens in 
the School of Mines, St. Petersburg, the University of St. Petersburg, 
and in the Museum of Comparative Zoology, Cambridge (Mass.), 
prove that the teeth always assumed the form noted above in the 
diagnosis of the family. A diagrammatic sketch of a tooth in the 

Fig. 5. 



\\\ 






Tooth of Ttyctodus obliquus, Pander, nat. size ; Devonian, Eussia. — A, inner 
aspect, showing symphysis, the base enveloped in matrix. B, oral aspect, 
the tritors marked by transverse lines. 

first-mentioned museum, showing the inner and oral aspects, is 
given in the accompanying woodcut (fig. 5). 



PTTCTODONTID^!. 39 

The following species are recognized : — 

Ptyctodus calceolus, J. S. Newberry, Eep. Geol. Surv. Ohio, vol. ii. 
pt. ii. (1875), p. 59, pi. lix. fig. 13 : Rinodus calceolus, 
Newberry & Worthen, Pal. Illinois, vol. ii. (1866), p. 106, 
pi. x. fig. 10. — Hamilton Group (Upper Devonian); Illinois 
and Iowa. [Abraded tooth, the type species of Rinodus.~] 

Ptyctodus obliquus, C. H. Pander, Ctenodipt. devon. Syst. (1858), 
p. 64, pi. viii. figs. 1-9, 11, 13-22 : Ptyctodus ancinnatus, 
C. H. Pander, ibid. p. 64, pi. viii. figs. 10, 12 : Aulacosteus 
cochleariformis and A. oviformis, E. von Eichwald, Leth. 
Rossica, vol. i. (1860), pp. 1548, 1550, pi. lvii. fig. 8.— 
Middle Devonian ; Governments of St. Petersburg, Nov- 
gorod, and the Baltic Provinces. [Abraded teeth ; School 
of Mines, St. Petersburg. The type species.] 

Genus RHYNCHODUS, Newberry. 
[Rep. Geol. Surv. Ohio, vol. i. pt. ii. 1873, p. 307.] 
In the type species of this genus, four teeth have been found 
associated in a group, suggesting that those of the upper and lower 
jaws were similar, a single pair occurring in each. 

The following species are known : — 

Rhynchodus eoccavatus, J. S. Newberry, Rep. Geol. Surv.Wisconsin, 

vol. ii. (1877), p. 397, and Palaeoz. .Fishes N. America 

(Mon. U.S. Geol. Surv. no. xvi. 1889), p. 50, pi. xxix. 

fig. 1. — Hamilton Group (Upper Devonian) ; Milwaukee, 

Wisconsin. 
Rhynchodus occidentalis, J. S. Newberry, Ann. New York Acad. 

Sci. vol. i. (1878), p. 192. — Hamilton Group; Iowa. 

[Columbia College, New York.] 
s, Bhynchodus secans, J. S. Newberry, Rep. Geol. Surv. Ohio, vol. i. 

pt. ii. (1873), p. 310, pi. xxviii. fig. 1, pi. xxix. figs. 1, 2, 

and Palseoz. Pishes N. America (1889), p. 47, gl. xxviii. 

figs. 1-3. — Corniferous Limestone (Middle Devonian) ; 

Ohio. [The type species, Columbia College.] 
Bhynchodus, sp. ind. : Physichthys hoeninghausii, H. von Meyer, 

Palseontogr. vol. iv. (1855), pi. xv. fig. 9 (errore). — 

Devonian ; Eifel, Germany. [Museum of Comparative 

Zoology, Cambridge, Mass.] 

Genus PAKffiOMYLUS, nov. 
In the type species of this genus (P. frangens) the symphysis is 
as broad as in Edaphodon. 



40 



ClilM.ttKOlDtil. 



The following species are placed here : — 

Palasomylus crassus : Rhynchodus crassus, J. S. Newberry, Rep. 

Geol. Surv. Ohio, vol. i. pt. ii. (1873), p. 312, pi. xxix. 

fig. 3, and Palaeoz. Fishes N. America (1889), p. 49, pi. 

xxviii. fig. 4. — Corniferous Limestone ; Ohio. [Columbia 

College, New York.] 
Palceomyhis frangens : Rhynchodus frangens, J. S. Newberry, 

op. cit. (1873), p. 311, pi. xxviii. figs. 2, 3, and op. cit. 

(1889), p. 48, pi. xxix. figs. 2, 3. — Corniferous Limestone; 

Ohio. [Columbia College.] 
Palceomylns greenei : Rhynchodus greenei, J. S. Newberry, op. cit. 

(1889), p. 51. — Hamilton Group ; Milwaukee, Wisconsin. 



Family SQUALORAIIDtE. 

Body depressed, but elongated. Head produced into a flat ros- 
trum, without lateral teeth. Dentition consisting of thin, trans- 
versely curved plates, without differentiated tritoral areas ; a single 
pair in the lower jaw, meeting at the symphysis, and two pairs in 
the upper jaw, the hinder pair being closely apposed in the median 
line anteriorly, but divergent posteriorly. Dorsal fin-spine absent. 
Males with a prehensile spine upon the snout. 



Genus SQUALORAJA, Riley. 
[Proc. Geol. Soc. vol. i. 1833, p. 484.] 
Syn. Spinacorhinus, L. Agassiz, Poiss. Foss., Feuill. 1837, p. 94. 

Rostrum much produced ; tail gradually tapering to a point. 
[Median fins unknown.] Teeth marked with a series of hard, 
parallel, longitudinal corrugations ; rostral spine of male slender and 
pointed, with expanded base and a cluster of large recurved denticles 
on the inferior aspect near its insertion ; dermal tubercles conical, 
radiately sculptured, sparsely arranged. Vertebral rings well cal- 
cified, consisting of several concentric lamellae. 

This genus has hitherto been regarded as a Selachian, though the 
Chimaeroid resemblance of its rostral region, the supports of its lateral 
line, &c, have been pointed out by W. Davies and the present 
writer. The skulls recorded below have a hyostylic appearance ; 
but the writer is indebted to Dr. R. H. Traquair for the information 
that the Edinburgh Museum acquired a specimen some years ago 
proving the arrangement to be truly autostylic, while a pair of 
vomerine teeth occurs in advance of the well-known lar^e dental 



SQUALOEAIID.E. 



41 



plates already described in the upper jaw. A recent examination 
of this unique fossil in Edinburgh has convinced the writer of the 
correctness of Dr. Traquair's determination of the affinities of the 
fish. 

Squaloraja polyspondyla, Agassiz. 

[Plate III. fig. 2.] 

1833. Squaloraia dolichognathos, H. Riley, Proc. Geol. Soc. vol. i. p. 484 

(specific name inappropriate). 
1837. Squaloraia dolichognathus, H. Riley, Trans. Geol. Soc. [2] vol. v. 

p. 83, pi. iv. 
1836. Spinacorhinus polyspondylus, L. Agassiz, Poiss. Foss. vol. iii. 

pis. xlii., xliii., and Feuill. p. 94. 
1843. Squaloraja polyspondyla, L. Agassiz, ibid. vol. iii. p. 381. 
1872. Squaloraja polyspondyla, W. Davies, Geol. Mag. vol. ix. p. 145, 

pi. iv. 

1885. Squaloraja polyspondyla, C. Hasse, Palgeontogr. vol. xxxi. p. 4, 
pi. i. figs. 2, 3. 

1886. Squaloraja polyspondyla, A. S.Woodward, Proc. Zool. Soc. p. 527, 
pi. Iv. figs. 1-5, 7, 8, and ibid. 1887, p. 481. 

Type. Imperfect skeleton ; Bristol Museum. 

The type species, usually not exceeding 0*45 in length. Head 
occupying more than one third of the total length ; distance between 
pectoral and pelvic arches two thirds as long as the head ; caudal 
region attenuated. Rostral spine of male slender, depressed oval in 
section, terminating bluntly and not excessively attenuated, occu- 
pying more than three quarters the length of the rostral cartilage ; 
claspers of male robust, with a small distal cluster of slender 
recurved hooklets. Dermal tubercles sparse, a regular series of 
prominent hooklets on each lateral margin of the tail. Mandibular 
and palatine teeth about six and a half times as long as their maxi- 
mum breadth, the symphysial portion somewhat raised and tumid. 

Form. Sf Loc. Lower Lias : Dorsetshire. 

The following specimens were all obtained from the Lower Lias 
of Lyme Regis. 

43307. Head, vertebral column, and fragments of pelvic fins, de- 
scribed and figured by W. Davies, loc. cit. 

Purchased, 1872. 

P. 2276. The nearly complete skeleton of a male, wanting only a 
small portion of the caudal region ; described and figured 
by the present writer, loc. cit. Purchased, 1882. 



I 

42 CHIM^KOIDEI. 

P. 2079. Portions of ,vertebral column and crushed cranium of an 
old individual, probably female ; vertebra figured by the 
present writer, loc. cit. pi. lv. fig. 8. Egerton Coll. 

P. 3184. Portion of skeleton of young female, ventral aspect, de- 
scribed and figured by the present writer, loc. cit. -passim, 
pi. lv. figs. 3, 4, 7. Ennishillen Coll. 

47402. Skull of male, dorsal aspect ; described and figured by the 
present writer, loc. cit. pp. 532, 534, pi. lv. fig. 2. 

Purchased, 1876. 

41354. Portion of rostral cartilage ; described and figured by 
W. Davies, loc. cit. p. 147, pi. iv. fig. 2. Purchased, 1869. 

41353. Portion of cranium of female, seen from below ; described 
and figured by W. Davies, loc. cit. p. 148, pi. iv. fig. 4. 

Purchased, 1869. 

43970. Detached dental plate, shown, of the natural size, in PI. III. 
fig. 2. As proved by other specimens, each ramus of the 
jaw was provided with a single plate of this character. 
The efficiency of the grind ing-surface is increased by a 
series of parallel longitudinal ridges, which represent the 
tritors and are distinctly worn down towards the outer 
functional border. Purchased, 1872. 

Some of the following specimens may belong to other species : — 

P. 6220. Imperfect rostral spine; described and figured by W. Davies, 
loc. cit. p. 148, pi. iv. fig. 3. Purchased. 

P. 3186. Imperfect rostral spine ; described and figured by the 
present writer, loc. cit. p. 531, pi. lv. fig. 5. 

Ennishillen Coll, 

P. 3187. Complete, much-curved rostral spine, exhibiting only 
dorsal aspect. Ennishillen Coll. 

P. 4574. Anterior two thirds of very large rostral spine. 

Ennishillen Coll. 

P. 4323. Two fragmentary abraded rostral spines. Ennishillen Coll. 

P. 2080. Broken fragment of vertebral column, showing longitudinal 
section of vertebrae. Egerton Coll. 

P. 3185, P. 4323 a. Fragments of vertebral column and incomplete 
rostral spine. Ennishillen Coll. 

41278. Vertebrae of very small individual. Purchased, 1869. 




MTRIACANTHID^. \ v? 43 

Squaloraja tenuispina, A. S. Woodward. 

1886. Squaloraja tenuispina, A. S. Woodward, Proc. Zool. Soc. p. 530, 
pi. lv. fig. 6. 

Type. Detached rostral spine ; British Museum. 
A small species known only by the rostral spine, which is slender 
and extremely acuminate. 

Form. Sf Log. Lower Lias : Lyme Regis, Dorsetshire. 

P. 2081. Type specimen. Egerton Coll. 

Genus CHALCODUS, Zittel. 

[Handb. Pakeont. vol. iii. 1887, p. 72.] 

A genus probably referable to the Squaloraiidse and known only 
by the dentition. Coronal surface of teeth smooth or finely punctate. 

Chalcodus permianus, K. A. von Zittel, Handb. Palaeont. vol. iii. 
(1887), p. 72, woodc. fig. 66. — Kupferschiefer ; Gliicks- 
brunn Thuringia. [Associated dental plates ; Palseonto- 
logical Museum, Munich.] The type and only known 
species. 



Family MYEIACANTHIDJE. 

Body elongated ; anterior dorsal fin above the pectorals, provided 
with a long, straight, robust spine. Teeth forming two (? or three) 
pairs of thin dental plates in the upper jaw, the hinder pair atten- 
uated mesially and not closely apposed in the median line ; lower 
dentition consisting of a pair of large dental plates, meeting at the 
symphysis, and a median incisor-like tooth in front. A few dermal 
plates present upon the head. Males with a large prehensile spine 
upon the snout. 

Synopsis of Genera. 

Palatine teeth larger than the vomerine Myriacanthus (p. 43). 

Palatine teeth smaller than the vomerine Chimceropsis (p. 51). 

Genus MYRIACANTHUS, Agassiz. 
[Poiss. Poss. vol. iii. 1837, p. 37.] 

Syn. Prognathodus, Sir P. Egerton, Quart. Journ. Geol. Soc. vol. xxviii. 
1872, p. 236. 
Metopacanthus, K. A. von Zittel, Handb. Paleeont. vol. iii. 1887, 
p. 110. 



/ 



44 | / CHIM-EEOIDEI. 

Rostral cartilage somewhat produced, bearing a terminal cutaneous 
flap. Mandibular tooth more or less massive in external appearance, 
though really a thin plate ; symphysial surface narrow ; oral surface 
undulating and covered by an extended, punctate, tritoral area, 
almost or quite continuous. Presymphysial tooth vertically elon- 
gated, bilaterally symmetrical, compressed antero-posteriorly, the 
inner aspect being flat or concave, the outer aspect convex. Pala- 
tine tooth thin, plate-like, triangular or irregularly quadrate in 
form, the outer margin being nearly straight, sharply deflected and 
thickened, the inner and posterior margins tapering gradually to a 
thin edge ; oral aspect with a continuous, punctate, tritoral area. 
Vomerine tooth smaller than the palatine, of triangular form, broad 
posteriorly, and provided either with a long anteriorly-directed 
process or with a distinct small tooth in front ; punctate tritoral 
area subdivided into rounded patches. Dorsal fin-spine long and 
slender, somewhat laterally compressed, with a large internal cavity ; 
sides more or less ornamented with small tubercles ; a series of 
large, thorn-shaped, spinous tubercles arranged along each edge of 
the flattened posterior face, passing into a single median row dis- 
tally, and a single series of similar denticles occupying at least 
part of the anterior border. Rostral spine of male elongated and 
pointed, with expanded base. Dermal plates tuberculated. 

Myriacanthus paradoxus, Agassiz. 
[Plate II. figs. 1-3.] 

1822. "External defensive organ," H. T. De la Beche, Trans. Geol. Soe. 

[2] vol. i. p. 44, pi. y. figs. 1, 2. 
1837. Myriacanthus paradoxus, L. Agassiz, Poiss. Foss. vol. hi. p. 38, 

pi. vi. 
1837. Myriacanthus retrorsus, L. Agassiz, ibid. p. 39, pi. viii a. figs. 14, 

15. [Base of spine ; Oxford Museum.] 
1843. Chimcera (Ischyodon) johnsonii, L. Agassiz, ibid. p. 344, pi. xl c. 

fig. 22. [Dentition ; British Museum.] 
1872. Prognathodus guentheri, Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. xxviii. p. 233, pi. vin\ [Dentition ; British Museum.] 
1889. Myriacanthus paradoxus, A. S. Woodward, Ann. Mag. Nat. Hist. 

[6] vol. iv. p. 279. 

Type. Dorsal fin-spines ; British Museum and Bristol Museum. 

The type species, of large size, the dorsal spine attaining a maxi- 
mum length of not less than 0*6. Dorsal spine oval in section, 
flattened posteriorly, and with a faint anterior longitudinal ridge : 
lateral tuberculations relatively large and sparse, arranged on a 
longitudinally striated surface ; anterior and posterior denticles very 



MYRIACANTHIDJ2. 45 

broad, laterally compressed and pointed, irregularly and widely 
spaced, occasionally present on part of the longitudinal median lino 
of the posterior face ; a few of the posterior denticles distally directed 
downwards, the others pointing upwards. Hinder upper tooth 
about twice as long as its maximum breadth. Maximum thickness 
of presymphysial tooth about one third its breadth, and more than 
twice as great as the thickness of the inner layer of dentine, which 
is continuous and uniform ; outer face of the tooth gently convex, 
the inner face slightly concave, but nearly flat. 

The genus Prognaihodus was founded upon the dentition of this 
species. 

Form. Sf Loc. Lower Lias : Lyme Regis, Dorsetshire. 

(i.) Dorsal Spines. 

P. 6095. One of the type specimens of Myriacanthus paradoocus, 
figured by Agassiz, torn. cit. pi. vi. figs. 1, 2, and previously 
figured, without name, by De la Beche, loc. cit. 

Old Collection. 

P. 3067. Another of the type specimens, figured by Agassiz, ibid. 
pi. vi. fig. 3. Enniskillen Coll. 

P. 3174. A very large crushed spine, about 0*65 in total length. 
The slender, compressed distal extremity is preserved, 
destitute of tubercles for a short extent ; and immediately 
below this space are remains of a few of the characteristic 
large posterior denticles. At about the middle of the 
spine, some of the last-mentioned denticles are unbroken, 
showing their acutely pointed, upwardly curved form. 

Enniskillen Coll. 

P. 3068, P. 3196. The greater portion of two equally large spines, 
the first being almost uncrushed and displaying several of 
the denticles. Enniskillen Coll. 

P. 1736. Much crushed similar specimen. Egerton Coll. 

P. 6179. Imperfect large spine, with denticles. Purchased, 1890. 

P. 6221. Fragments of a very large spine, showing part of the 
smooth distal extremity. 

P. 3071. Distal half of a somewhat smaller spine, with well- 
preserved denticles. Enniskillen Coll. 

P. 1737. Similar, but more imperfectly preserved specimen. 

Egerton Coll. 



46 CHIILEROIDEI. 

P. 3069. Remains of distal two thirds of spine, showing part of the 
posterior face. For some distance from the pointed 
extremity this face is flattened or transversely concave, 
but more proximally a faint median longitudinal ridge 
begins to appear, bearing one or two denticles at wide 
intervals. Ennishillen Coll. 

P. 3197, P. 3197 a, P. 4454 a. The distal half and two portions of 
the distal half of small spines. The third specimen shows 
some of the downwardly pointing posterior denticles, and 
the non-tuberculated apical portion is very short. 

Ennislcillen Coll. 

P. 341. Distal half of small spine, showing denticles. 

Purchased, 1881. 

P. 427. Fragment of small spine, showing denticles. 

Par chased, 1882. 
37376. Fragment of small spine, showing denticles. 

Purchased, 1863. 

41321. Fragment of large spine, showing denticles. 

Purchased, 1869. 

(ii.) Dentition. 
P. 477. Type specimen of the so-called Ischyodus johnsoni, briefly 
described, with an imperfect figure, by Agassiz, loc. cit. 
The presymphysial tooth (" intermaxillaire," Agassiz) lies 
between, the two mandibular teeth (" maxillaires supe- 
rieurs," Agassiz), of which that of the right side is almost 
destroyed. One of the palatine teeth (" maxillaire infe- 
rieur gauche," Agassiz) is also exposed, from the oral 
aspect, but its outline is partly obscured or broken away. 
None of the teeth can be removed from the matrix, owing 
to its hardness, and they are not arranged so as to permit 
of the satisfactory drawing of the entire specimen ; the 
characteristic left mandibular tooth is, however, shown 
from the oral aspect in PL II. fig. 3. The symphysial 
facette of this tooth is narrow, and in the middle of the 
oral face there is a broad prominence, separated from the 
symphysial and post-oral margins by deep depressions ; the 
extended, tubulated, tritoral area seems to have been con- 
tinuous over the oral face, though rapidly thinning towards 
the outer margin and evidently originally covered with a 
stratum of hard dentine upon the inner face. The pre- 
symphysial tooth seems to have been bilaterally symme- 
trical, the tritoral portion forming a thick layer upon the 



MYRIACANTHIDiE. 47 

slightly concave inner face, and consisting of tubules 
arranged at right angles to that face (PI. II. fig. 2 b). The 
palatine tooth, so far as preserved, exhibits a gently tumid 
oral surface, completely covered by the tritoral area, 
which is again enveloped by a thin layer of hard dentine 
inwardly. Egerton Coll. 

P. 4664. Type specimen of Prognathodus guentheri, described and 
figured by Egerton, loc. cit. The fossil exhibits the 
anterior aspect of the mandible and all the teeth, except 
the right palatine, the mouth being opened and the upper 
dentition displayed from the oral aspect. The mandibular 
cartilage is flattened, so that both rami lie in one plane, 
and there is no suture at the symphysis. Two small 
labial cartilages rest upon its median portion, and at the 
left extremity is a triangular dermal plate, ornamented 
with tubercles and provided with two large marginal 
processes, as shown in Egerton's figure. The dentition is 
re-figured in the accompanying PI. II. fig. 1. The mandi- 
bular teeth (" maxillary, "Egerton) are considerably broken 
(mdi) and the oral face is evidently abraded, so that the 
punctate tritoral areas appear as if confined to the promi- 
nences. The presymphysial tooth (ps.) displays the outer 
convex face, coarsely striated longitudinally ; and the 
irregularity of its inferior extremity suggests that that 
was its point of insertion. Only the anterior half of the 
oral face of the left palatine tooth (" mandibular tooth 1," 
Egerton) is exposed (pi.) ; but the whole of the attached 
surface of this tooth has been extricated from the matrix 
since its description by Egerton, and its precise outline 
can thus be ascertained. It exactly agrees with the 
corresponding tooth of the new specimen (No. P. 151) 
described below ; but the only detail that can be 
observed upon the oral aspect is the presence of a broad 
depression extending obliquely backwards from the antero- 
external angle, and this was perhaps not covered by the 
tritoral area, which seems to extend over all other parts. 
The abruptly deflected anterior margin of the palatine 
tooth abuts against the small triangular vomerine tooth 
(" mandibular tooth 2," Egerton), in advance of which is 
the still smaller tooth (" mandibular tooth 3," Egerton), 
either as a separate element or merely an accidental dis- 
memberment. The principal vomerine tooth (v.) has a 
gently tumid oral surface, with one large tritoral area and 



48 CHIM.EROIDEI. 

five or six small, irregularly arranged, isolated patches ; 
the oral aspect of the small anterior tooth (x.) is marked 
with large, parallel, transverse, mammillated ridges. 

EnnuTcillen Coll. 

P. 151. The complete dentition exposed from above, and partly from 
below, associated with three dermal plates ; noticed by 
the present writer in the Aon. Mag. Nat. Hist. [6] vol. iv. 
(1889), p. 278. The specimen is shown, of the natural 
size, in PI. II. fig. 2, and the parts are marked in accord- 
ance with the following description. The mandibular 
teeth (md.) are both shown from the inner and oral aspect, 
though partly obscured by the overlying palatines (pi.); 
and, so far as preserved, each seems to be precisely similar 
to the corresponding tooth in the group No. P. 477 (PL II. 
fig. 3). The presymphysial tooth, situated close to the 
position of the mandibular symphysis on the opposite side 
of the slab, is considerably crushed and broken, and thus 
appears relatively broader and more flattened than in the 
fossils described above. The palatine teeth {pi.) are large, 
thin, and plate- like, but unfortunately only exposed from 
the attached surface. Each of these teeth is elongated 
antero-posteriorly and must have originally possessed a 
nearly straight outer margin, somewhat thickened, and 
sharply deflected; the short anterior margin, forming an 
acute angle with the outer, is likewise deeply deflected 
and abuts against the vomerine tooth ; but the inner and 
posterior margins are thin edges of nearly equal length, 
and there is no appearance of the close apposition of the 
right and left teeth in the median line. If the attached 
surface be approximately parallel to the oral surface in 
these teeth, there is a longitudinal median elevation, and 
this gradually disappears in the broad posterior extremity 
of the plate. The triangular vomerine tooth (v.) on each 
side is also seen to be thin and plate-like in form, its 
robust appearance, when viewed from the oral aspect, 
being due to the sharp deflection of all the margins. The 
pair of small anterior teeth (x) in advance of the vomerine 
is somewhat displaced ; but the oral aspect of one (PI. II. 
fig. 2 a) is well displayed, and exhibits the characteristic, 
mammillated, transverse ridges, consisting apparently of 
laminated dentine. Purchased, 1880. 



MYRIACANTHID.E. 49 

Myriacanthus granulatus, Agassiz. 

[Plate II. fig. 4; Plate III. figs. 3, 4.] 

1887. Myriacanthus granulatus, L. Agassiz, Poiss. Foss. vol. iii. p. 40, 

pi. viii. a. fig. 16. 
1837. Leptacanthus tenuispinus, L. Agassiz, ibid. p. 27, pi. i. figs. 12, 13. 

[Spine ; British Museum.] 
1871. Ischyodus orthorhinus, Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. xxvii. p. 275, pi. xiii. [Head, &c. ; British Museum.] 
1887. Metopacanthus orthorhinus, K. A. von Zittel, Handb. Palaeont. 

vol. iii. p. 111. 
1889. Myriacanthus granulatus, A. S. Woodward, Ann. Mag. Nat. 

Hist. [6] vol. iv. p. 279. 

Type. Imperfect dorsal fin-spine ; British Museum. 

A species of comparatively small size, the dorsal spine attaining 
a maximum length of about 0*18. Dorsal spine much laterally- 
compressed, with an acute anterior edge ; lateral tubercles relatively 
small and closely arranged, absent upon a long extent from the 
much attenuated apex ; anterior and posterior denticles long, com- 
paratively slender, and closely arranged ; a long series of the pos- 
terior denticles distally directed downwards, the others pointing 
upwards. Maximum thickness of presymphysial tooth about one 
third its breadth, and the tritor confined to a narrow median 
band, lenticular in section ; outer face of the tooth strongly convex, 
with a sharply rounded, median, longitudinal elevation, the inner 
face equally concave. 

This is the type species of the so-called Metopacanthus. 

Form. Sf Log. Lower Lias : Lyme Regis, Dorsetshire. 

43050. Head and associated dorsal fin-spine in position, described 
and figured by Egerton, he. cit., as the type specimen of 
Ischyodus orthorhinus, and subsequently adopted as the 
type of Metopacanthus by Zittel, loc. cit. The rostral spine 
is shown to be covered superiorly with granulations, finer 
and more closely arranged than those of the sides of the 
dorsal spine. Purchased, 1871. 

P. 4575. Remains of the head with dentition, and the basal half of 
the rostral spine ; also a fragment of the dorsal spine, 
probably found associated. The jaws and a few dermal 
tubercles are shown, of the natural size, in PL II. fig. 4, 
and the parts are indicated by the lettering. A portion of 
the cartilage of the mandible is seen from the outer ante- 
rior aspect ; and overlapping the oral margin is observed 
the pair of large mandibular teeth (rnd.). Immediately 

PART II. e 



50 CHlMiEKOIDEI. 

above the right mandibular tooth rests the small incisor- 
like presymphysial tooth (ps.) r which is shown in side view 
and transverse section, of three times the natural size, in 
figs. 4 a, 4 b. This tooth is much worn at its rounded 
functional extremity, and appears in transverse section 
(fig. 4 b) as if bent upon its mesial longitudinal line, which 
is in the form of a rounded ridge externally and a deep 
concavity internally ; the tubular dentine does not cover 
the whole of the inner face, but forms a band occupying 
the greater part of the width of the concavity. The pair 
of anterior upper teeth (v.) is displayed from the oral 
aspect, each consisting of a broad triangular hinder portion, 
and a narrow quadrangular anterior portion, the latter 
crossed by few transverse ridges of laminated dentine. A 
fragment of one of the hinder upper teeth (jol.) is too 
imperfect for description,, Some of the thorn-shaped der- 
mal tubercles, upon expanded bases, evidently from the 
rostral spine, occur higher upon the slab (t.) : and the 
basal half of the spine itself is shown from the dorsal 
aspect immediately adjoining. This spine expands at its 
base more gradually than that of Squaloraja, which it 
otherwise resembles in form : and there are traces of a 
very fine superficial granular ornament. EnnisJcillen Coll. 

P. 1158. Fragmentary remains of head and dorsal fin-spine. Por- 
tions of the hinder pair of upper teeth are shown from the 
attached surface, and further posteriorly there is a trian- 
gular dermal plate, exposed from the outer aspect. This 
plate is raised to a somewhat excentric acuminate apex, 
and is covered with tuberculations arranged more or less 
in radiating lines ; it is shown, of twice the natural size, 
in PI. III. fig. 4. The dorsal spine is much crushed and 
abraded, but exhibits a few downwardly pointing posterior 
denticles distally, while a long series of upwardly directed 
denticles is preserved on the anterior border. Egerton Coll. 

P. 3099. Left mandibular tooth, exposed from the oral aspect, and 
shown, of the natural size, in PL III. fig. 3. The sym- 
physis (fig. 3, a) is narrow and shows the characteristic 
bevelling (s), much extended, probably for the accommo- 
dation of the mediau incisor-like tooth ; while the oral 
surface is undulating, with one oblique median ridge and 
a somewhat raised post- oral border, neither parallel with 
the symphysial border, but much less nearly vertical. The 



MYRTACANTTHD.aE. 51 

punctate dentine appears to be exposed only in a long 
narrow band on each of these two elevations. 

Ennislcillen Coll. 

P. 3070. Imperfectly preserved distal portion of dorsal spine, the 
type specimen of Myriacanthus granulatus. 

Ennislcillen Coll. 

P. 2848. Much broken distal extremity of dorsal spine in hard 
matrix, the type specimen of Leptacanthus tenuispinus. 

Ennislcillen Coll. 
43065. Much abraded dorsal spine, wanting the basal portion. 

Purchased, 1871. 
P. 3072, P. 4454 b-e. Two imperfectly preserved dorsal spines, 
wanting the basal portion ; also three fragments. 

Ennislcillen Coll. 
P. 4876. Crushed spine, wanting anterior denticles. 

Purchased, 1885. 
41382. Distal portion of spine. Purchased, 1869. 

The following specimen is also probably referable to Myria- 
canthus : — 

P. 2850. Distal portion of dorsal spine, exhibiting a nearly smooth, 
slender, arcuated extremity, with four widely-spaced, large 
and downwardly curved posterior denticles, shown, of the 
natural size, in PI. III. fig. 5 ; Lower Lias, Lyme Regis. 

Enniskillen Coll. 



Genus CHIMiEROPSIS, Zittel. 
[Handb. Palasont. vol. iii. 1887, p. 113.] 
Mandibular tooth with an undulating or gently curved oral 
surface and margin, with an extended, punctate, tritoral area. 
Presymphysial tooth vertically elongated, bilaterally symmetrical ; 
the inner aspect flat or concave, the outer aspect convex. Palatine 
tooth thin, plate-like, triangular, and pointed behind. Vomerine 
tooth somewhat larger than the palatine, triangular, and pointed 
anteriorly ; oral surface with an anterior and a posterior punctate 
tritoral area. Dorsal fin-spine elongated, more or less laterally 
compressed, and the sides ornamented with tuberculations ; a series 
of large, thorn-shaped, spinous tubercles arranged along each side 
of the flattened posterior face, and a single series of similar denticles 
occupying at least part of the anterior border. Dermal plates 
tuberculated ; trunk covered with small, conical, radiately grooved 
granules. {Zittel.) 

e 2 



52 CHIMJ2R0IDEI. 

Chimaeropsis paradoxa, Zittel. 

1843. " Knochen," H. von Meyer, in Minister's Beitr. Petrefakt. i. p. 96, 

pi. viii. fig. 1. 
l887. Chimceropsis paradoxal. A. von Zittel, Handb. Palaeont. vol. iii. 

p. 114, woodc. fig. 126. 
1887. Chimceropsis paradoxa, J. Biess, Palaeontogr. vol. xxxiv. p. 21, 

pi. ii. figs. 9-11, pi. iii. figs. 1-10. 

Type. Imperfect skeleton ; Palaeontological Museum, Munich. 

The type species, attaining a length of not less than one metre ; 
dorsal spine in such a specimen 0*15 in length. Two closely 
apposed, angulated dermal plates on either side of the back of the 
head. Dorsal fin-spine rapidly tapering, gently arched, and all the 
anterior denticles pointing upwards. Mandibular tooth robust in 
appearance, with prominent beak and gently excavated, scarcely 
undulating oral margin; presymphysial tooth sharply rounded in 
front. Vomerine tooth about one and a half times as long as its 
maximum width behind ; the maxillary tooth much narrower. 

Form, fy Log. Lower Kimmeridgian (Lithographic Stone) : Bavaria. 

Not represented in the Collection. 

To Chimceropsis also must doubtless be assigned the first of the 
dorsal fin-spines described as follows : — 

Myriacanthus franconicus, G. von Minister, Beitr. Petrefakt. iii. 
(1840), p. 127, pi. iii. fig. 8. — Upper Jurassic ; Babenstein, 
Bavaria. 

Myriacanihus vesiculosus, G. von Minister, ibid. v. (1842), p. Ill, 
pi. vi. fig. 3. — Corallian ; Lindnerberg, Hanover. [? Frag- 
ment of Asteracanihus.~] 

A spine from the Lower Carboniferous of Russia, certainly not of 
the Myriacanthidae, is named Myriacanthus semigranulatus, H. Ro- 
manowsky, Bull. Soc. Imp. Nat. Moscou, 1864, pt. ii. p. 167, pi. iv. 
fig. 34. 



Family CHEVLERIDJE. 

Body elongated : anterior dorsal fin above the pectorals, provided 
with a long, straight, robust spine. Teeth forming two pairs of 
robust dental plates in the upper jaw, both pairs thickened and 
closely apposed in the longitudinal mesial line of the mouth ; lower 
dentition consisting of a single pair of large, beak-shaped plates, 
meeting at the symphysis ; most of the plates with several tritoral 
areas. Dermal plates absent. Males with a prehensile spine upon 
the snout. 






CHIM2EKID.2E. 53 

The genera and species of this family are distinguished by the 
characters of the dentition ; and in the case of most of the extinct 
forms this is the only part of the skeleton available for study. A 
convenient nomenclature for the various parts of the teeth has thus 
been proposed by E. T. Newton l ; and this will be adopted in^ the 
following pages, except that here the term " tritor " is substitute^ 
for " tooth." 

Synopsis of Genera. 

A.. Outer tritors of mandibular teeth two (an- 
terior and posterior). 
Mandibular tooth with narrow symphysial 

surface, and external thickening along 

the oral border. Palatine tooth with 

deeply cleft posterior border, and the 

tritors in an outer and an inner lon- 
gitudinal series Ganodus (p. 55). 

Mandibular tooth with narrow symphysial 

surface, and external thickening along 

the oral border. Palatine tooth with 

four tritors, two being inner, one 

median, and one outer ; no posterior 

excavation Ischyodus (p. 59). 

Mandibular tooth with broad symphysia 

surface, and no external thickening 

along the oral border. Palatine tooth 

with three tritors, two being inner and 

one outer ; no posterior excavation . . Edaphodon (p. 73) . 

B. Outer tritors of mandibular teeth absent. 

Mandibular tooth with narrow symphysial 
surface, and external thickening along 
the oral border. Palatine tooth with 
single large tritor divided into two 
processes anteriorly Callorhynehus (p. 87). 

C. Mandibular teeth thin, with the outer tritors 

small and numerous, and symphysis 
narrow. 

Mandibular tooth with two rows of dot-like 
beak-tritors and similar outer tritors ; 
median tritor absent. [Palatine tooth 
unknown.] Elasmodeetes (p. 88). 

Mandibular tooth with large beak-tritor, 
this and the outer tritors being lami- 
nated ; median tritor present. Pala- 
tine tooth with four tritors, two being 
inner, one median, and one outer, the 
three first with tendency to fusion . . Elasmodus (p. 88). 

1 Chimaeroid Fishes, Brit. Cretaceous Rocks (Mem. Geol. Surv. 1878), p. 4. 



54 



CHIMJ5E0IDEI. 



Mandibular tooth with two or more beak- 
tritors and numerous dot-like outer 
tritors ; median tritor present. Pala- 
tine tooth with variable inner tritors 
and a series of small outer tritors .... Chimeera (p. 91). 

The characters of the oral aspect of the palatine and mandibular 
teeth in these genera are indicated in a diagrammatic manner in the 
figures given below. 

Fig. 6. 




Diagram of the oral aspect of the left palatine tooth in the principal genera 
of Chirnaeridag, showing the arrangement of the tritors. — 1. Ganodv.s. 
2. Ischyodus. 3. Edaphodon. 4. Callorhynchus. 5. Elasmodus, 6. Chi- 



Fig. 7. 




Diagram of the inner aspect of the left mandibular tooth in the principal genera 
of Chimaeridse, showing the arrangement of the tritors and the extent of 
the symphysis. Nos. as in fig. 6, with addition of 7- Elasmodectes. 






CFTTM iERTD M. 55 

Genus GANODUS, Agassiz (emend. A. S. W.) 1 . 

[Poiss. Foss. vol. iii. 1843, p. 339.] 

Syn. Leptacanthus, L. Agassiz, ibid. 1837, p. 27 (in part). 
Psittacodon, L. Agassiz, ibid. 1843, p. 340 (in part). 

An imperfectly known genus comprising species only of small 
size. Mandibular tooth as in Ischyodiis. Palatine tooth robust, 
with a well-defined hard layer upon the outer aspect immediately 
above the oral margin ; posterior border deeply notched, the sinus 
continued forwards as a median longitudinal groove, gradually 
becoming shallower, and separating the inner from the outer tritors ; 
inner tritors forming a narrow longitudinal band, more or less dis- 
continuous ; outer tritors similar, but smaller, and the two series 
usually connected anteriorly. 

As remarked by Agassiz, the median and outer tritors of the 
mandibular teeth are remotely placed and closely approximated ; 
they are, however, never fused together, and the characters of the 
palatine teeth only are sufficient to justify the separation of the 
genus from Ischyodus. 

Ganodus oweni, Agassiz. 
[Plate I. fig. 9.] 

1843. Chimcera (Ganodus) owenii, L. Agassiz, Poiss. Foss. vol. iii. 

p. 347, pi. xL figs. 6, 7. 
1843. Ischyodus oiveni, Sir P. Egerton, Proc. Geol. Soc. vol. iv. p. 156. 
1847. Ganodus oweni, Sir P. Egerton, Quart. Journ. Geol. Soc. vol. iii. 

p. 352. 
1890. Ganodus oweni, A. S. Woodward, Proc. Geol. Assoc, vol. xi. 

p. 303. 
(?) 1890. Ganodus sp., A. S. Woodward, ibid. pi. iii. fig. 4. 

Type. Theoretically associated mandibular and palatine teeth ; 
British Museum. 

Mandibidar tooth with a gently wavy oral margin and a relatively 
long post-oral margin much less vertically inclined than the sym- 
physial margin ; median tritor immediately behind and below the 
anterior outer tritor, somewhat narrower than the space between it 
and the symphysial margin, and notched antero-superiorly. (?) Pala- 
tine tooth with the inner tritoral series almost continuous in its 
posterior half, the outer series consisting of minute, well- separated 
tritors. 

1 Sir Philip Egerton states (Quart. Journ. Geol. Soc. vol. iii. 1847, p. 350) 
that he defined this genus in 1843. There does not appear, however, to be any- 
published record. 



56 CHIM^ROIBEl. 

This may be regarded as the type species of the genus as here 
defined. 

Form. <$■ Loc. Bathonian (Stonesfield Slate) : Stonesfield, Oxford- 
shire. 

P. 486. Right mandibular tooth, inner aspect, to be regarded as the 
type specimen ; figured by Agassiz, torn. cit. pi. xl. fig. 7. 

Egerton Coll. 

P. 3100, P. 3105 a. Two left mandibular teeth, exhibiting the inner 
aspect, labelled by Agassiz. Enniskillen Coll. 

36584. Broken left mandibular tooth, inner aspect. 

Purchased, 1862. 

P. 5108. Left mandibular tooth, outer aspect. 

Presented by J. E. Lee, Esq., 1885. 

P. 485. Eight palatine tooth, exhibiting only the superior aspect, 
figured by Agassiz, torn. cit. pi. xl. fig. 6. Egerton Coll. 

P. 1133. Left palatine tooth, oral aspect, figured in Proc. Geol. Assoc, 
vol. xi. pi. iii. fig. 4. Egerton Coll. 

P. 3100 b, C. Two similar left palatine teeth, one being shown, of the 
natural size, in PI. I. fig. 9. The oral aspect not being 
exposed in no. P. 485, these two specimens, with no. 
P. 1133, cannot be precisely compared, but their identity 
is probable and one is labelled " Chimcera owenii, Buckl.," 
in Agassiz's handwriting. Enniskillen Coll. 

P. 3100 a. Right vomerine tooth, resembling that of Ischyodus in 
form, and labelled by Agassiz as pertaining to this species. 

Enniskillen Coll. 
Two "species" of Ganodus — G. falcatus, Egerton 1 , and G.psitta- 
cinus, Egerton 2 — have also been founded upon mandibular teeth 
exhibiting the external aspect, and are not yet distinguishable with 
certainty from G. oweni. Both type specimens were obtained from 
the Stonesfield Slate, and are contained in the Egerton Collection. 
Of the left mandibular tooth described and figured as G. falcatus 
(P. 482), it is not improbable that the form of the oral margin and 
the prominence of the beak are due to accident ; and, though 

1 Quart. Journ. Geol. Soc. vol. iii. (1847), p. 352. Chimcera falcata, Proc. 
Geol. Soc. vol. iv. (1843), p. 154. Ischyodus falcatus, Sir P. Egerton, ibid. 1843, 
p. 156. Chimcera {Psittacodon) fcdcata, L. Agassiz, Poiss. Foss. vol. iii. (1843), 
p. 349, pi. xl. c. fig. 13. 

2 Quart. Journ. Geol. Soc. vol. iii. (1847), p. 352. Chimcera psittacina, Proc. 
Geol. Soc. vol. iv. (1843), p. 153. Ischyodus psittacinus, Sir P. Egerton, ibid. 
1843, p. 156. Chimcera {Psittacodon) psittacina. L. Agassiz, Poiss. Foss. vol. iii. 
(1843), p. 350, pi. xl. c. fig. 12. r 



chim^rid^. 57 

differing in being of much smaller size, the right mandibular tooth 
described and figured as G. psittacinus (P. 484) displays a contour 
very suggestive of that of G. oweni. 

Closely related either to G. oweni or to G. dentatus is the following 
small left mandibular tooth, which exhibits only the outer aspect : — 

P. 481. Type specimen of Chimcera neglecta, Egerton, Proc. Geol. 
Soc. vol. iv. (1843), p. 153, subsequently named Ischyodus 
neglectus, Egerton, ibid. p. 156, and Ganodus neglectus, 
Egerton, Quart. Journ. Geol. Soc. vol. iii. (1847), p. 352, 
and described and figured by Agassiz, Poiss. Eoss. vol. iii. 
(1843), p. 347, pi. xl. c. fig. 11, under the name of Chimcera 
(Ganodus) neglecta; Stonesfield Slate, Stonesfield. 

Egerton Coll. 
Ganodus dentatus, Egerton. 
[Plate I. fig. 10.] 

1847. Ganodus dentatus, Sir P. Egerton, Quart. Journ. Geol. Soc. 
vol. iii. p. 353. 

Type. Left mandibular tooth ; British Museum. 

Mandibidar tooth with a prominently sinuous oral margin and a 
relatively long post-oral margin, less vertically inclined than the 
symphysial margin ; median tritor narrow, immediately behind and 
below the anterior outer tritor ; both outer tritors exposed as a 
vertical series of tubercles. 

Form. <$f Log. Bathonian (Stonesfield Slate) : Stonesfield. 

P. 614. Type specimen, shown, of twice the natural size, in PL I. 
fig. 10. Egerton Coll. 

Ganodus rugulosus, Egerton. 

[Plate I. fig. 11.] 

1843. Chimcera rugulosa, Sir P. Egerton, Proc. Geol. Soc. vol. iv. p. 154. 

1843. Ischyodus rugulosus, Sir P. Egerton, ibid. p. 156. 

1843. Chimcera (Ganodus) rugulosa, L. Agassiz, Poiss. Foss. vol. iii. 

p. 347. 
1847. Ganodus rugulosus, Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. iii. p. 352. 

Type. Imperfect right mandibular tooth ; British Museum. 

Mandibidar tooth with a very gently sinuous oral margin and a 
relatively long post-oral margin, much less vertically inclined than 
the symphysial margin ; median tritor small and narrow, situated 
well behind and below the anterior outer tritor ; both outer tritors 
very small. 

Form. 4' Loc. Bathonian (Stonesfield Slate): Stonesfield. 



58 CHIM^EOIDEI. 

P. 600. Type specimen, almost detached from matrix and much 

abraded externally. Egerton Coll. 

P. 5152. Right mandibular tooth exhibiting relatively larger tritors, 

but probably of this species, shown, of the natural size, in 

PI. I. figs. 11 a, b. Egerton Coll. 

P. 3105. Imperfect left mandibular tooth, outer aspect. 

Enniskillen Coll. 
A supposed distinct species is founded upon a right mandibular 
tooth exhibiting only the outer aspect; but it is not capable of 
definition and precise separation from G. rugulosus. The original 
specimen was described as Chimara curvidens, Egerton, Proc. Geol. 
Soc. vol. iv. (1843), p. 154, and subsequently named Iscliyodus 
curvidens, Egerton, ibid. p. 156, and Ganodus curvidens, Egerton, 
Quart. Journ. Geol. Soc. vol. iii. (1847), p. 352 ; it is placed first in 
the following series of teeth from the Stonesfield Slate, which repre- 
sent the " species " in the collection : — 

P. 599. Type specimen, shown, of natural size, in PI. I. fig. 12. 

Egerton Coll. 
P. 3104. More imperfect left mandibular tooth of similar form. 

EnnisTcillen Coll. 
28595. Small right mandibular tooth ; Eyeford, Gloucestershire. 

Purchased, 1853. 

Ganodus sp. 

[Plate I. fig. 13.] 
A single example of a palatine tooth from the Stonesfield Slate 
(P. 3107. EnnisTcillen Coll.) indicates an unusually large species of 
Ganodus. The specimen is of the right side and is shown, of the 
natural size, from the oral aspect, in PI. I. fig. 13 ; the inner tritors 
are few, large, and well-separated, and the outer tritors have only 
three minute representatives. It is possible that the fossil pertains 
to the same species as the imperfect right mandibular tooth described 
as CTiimcera bucklandi, Egerton, Proc. Geol. Soc. vol. iv. (1843), 
p. 153, Iscliyodus bucklandi, Egerton, ibid. p. 156, and subsequently 
described and figured by Agassiz, Poiss. Eoss. vol. iii. (1843), p. 343, 
pi. xl. c. fig. 19, under the name of Cliimcera (IscJiyoclon) bucklandi, 
afterwards assigned to Ganodus by Egerton, Quart. Journ. Geol. Soc. 
vol. iii. (1847), p. 352. This specimen, however (P. 478. Egerton 
Coll.), is too imperfect both for generic and specific determination. 

To Ganodus, also, must probably be assigned the following small 
dorsal fin-spines from the Stonesfield Slate, all obtained from Stones- 
field, unless otherwise stated : — << 



CHIM^KID-ffl. 59 

P. 2846-7. One of the type specimens of Leptacanthus semistriatus, 
Agassiz, figured, in the Poiss. Foss. vol. iii. pi. vii. fig. 6 ; 
also two larger portions of similar spines. 

Enniskillen Coll. 

47975-77. Portions of three similar spines. 

Presented by the Hon. Robert Marsham, 1877. 

P. 251. Abraded spine of the same " species." 

Presented by J. Wood-Mason, Esq. 1880. 

P. 2213. Two nearly complete similar spines. Egerton Coll. 

P. 4173. Impression of a similar spine labelled by Agassiz thns : — 
" Peut-etre le rayon du Psammodus magnus ; decrit sous 
le nom de Leptacanthus semistriatus." Enniskillen Coll. 

P. 3108. Type specimen of Leptacanthus serratus, Agassiz, described 
and figured in the Poiss. Foss. vol. iii. (1837), p. 29, 
pi. vii. fig. 1. Enniskillen Coll. 

28596. Portion of distal half of a similar spine; Eyeford, near 
Naunton, Gloucestershire. Purchased, 1853. 

P. 6222. Crushed portion of a similar spine. 



Genus ISCHYODUS, Egerton. 

[Proc. Geol. Soc. vol. iv. 1843, p. 155.] 

Syn. Leptacanthus, L. Agassiz, Poiss, Foss. vol. iii. 1837, p. 27 (in part). 
Auluxacanthus, H. E. Sauvage, Catal. Poiss. Form. Second. Bou- 

lonnais (Mem. Soc. Acad. Boulogne, vol. ii.), 1867, p. 63. 
Chimcer acanthus, F. A. Quenstedt, Der Jura, 1858, p. 347. 

Mandibular tooth more or less massive, with a well-defined hard 
layer upon the outer aspect immediately below the oral margin ; one 
anterior tritor usually present, sometimes several; one median 
tritor, and two or more external tritors. Palatine tooth very robust, 
with a well-defined hard layer upon the outer aspect immediately 
above the oral margin ; four tritors present, two being inner, one 
median, and one outer. Vomerine tooth more or less quadrate in 
side view, with tritors upon the oral margin ; post-oral region not 
laterally expanded, and usually with a definite hard thickening. 
Dorsal fin-spine laterally compressed, smooth or longitudinally 
striated, with a double series of posterior denticles. Head-spine of 
male short, arched, with a terminal cluster of denticles. 



60 



CHIMJGItOIDEI. 



Ischyodus colei (Agassiz). 

[Plate I. fig. 14.] 

1843. Chimeera (Ganodus) colei, L. Agassiz {ex Buckland, MS.), Poiss. 

Foss. vol. iii. p. 346, pi. xl. figs. 8-10. 
1843. Ischyodus colli, Sir P. Egerton, Proc. Geol. Soc. vol. iv. p. 156. 
1847. Ganodus colei, Sir P. Egerton, Quart. Journ. Geol. Soc. vol. iii. 

p. 352. 
1890. Ischyodus colei, Woodward k Sherborn, Cat. Brit. Foss. Verte- 

brata, p. 105. 

Type. Theoretically associated mandibular and palatine teeth ; 
British Museum. 

(?) Mandibular tooth with a gently wavy oral margin and a, 
relatively long post-oral margin nearly parallel to the symphysial. 
Palatine tooth with all the tritors of small size, the posterior inner 
being larger than the other three taken together, and the median 
tritor the smallest of all. 

The type specimen of the mandibular tooth not being sufficiently 
perfect for definition, the palatine tooth may be regarded as the 
type of the species. 

Form. <Sf Loc. Bathonian (Stonesfield Slate) : Oxfordshire. 

P. 1134 a. Right mandibular tooth, outer aspect, much abraded, 
figured by Agassiz, torn. cit. pi. xl. fig. 8 ; Stonesfield. 

Egerton Coll. 

P. 480. Left palatine tooth, oral aspect, figured by Agassiz, ibid. 
fig. 9, and re-figured in PL I. fig. 14 ; Stonesfield. 

Egerton Coll. 

P. 1134. Bight palatine tooth, superior aspect ; Stonesfield. 

Egerton Coll. 

P. 3101-2. Four palatine teeth, one showing the superior aspect, 
the others the oral aspect ; Stonesfield. 

Enniskillen Coll. 

Ischyodus emarginatus, Egerton. 

1843. Chimeera {Ischyodus) emarginata, Sir P. Egerton, Proc. Geol. Soc. 

vol. iv. pp. 154, 156. 
1843. Chimeera {Ischyodon) tessoni, L. Agassiz, Poiss. Foss. vol. iii. 

p. 342, pi. xl. fig. 19. [Mandibular tooth ; British Museum.] 

Type. Left mandibular tooth ; British Museum. 
This species is only provisionally retained distinct from I. egertoni, 
the difference of proportions not sufficing to justify its separation. 



CHTM^KIDiE. 61 

The posterior outer tritor appears to be much more feebly developed 
thau in the last-named species, but otherwise the arrangement is 
similar. Many Kimmeridgian fossils, presumably referable to /. 
egertoni, exhibit as much antero-posterior elongation as those placed 
here j and short and long varieties of the mandibular teeth have 
also been observed in other species, e. g. /. thurmanni (/. brevi- 
rostris, Newton). 

Form. <Sf Log. Bathonian : Oxfordshire, Gloucestershire, and 
Normandy. 

P. 3106. Left mandibular tooth, described as the type specimen by 
Egerton, loc. cit. ; Stonesfield Slate, Stonesfield, Oxford- 
shire. Enniskillen Coll. 

P. 5150. Imperfect right mandibular tooth, outer aspect; Stones- 
field. Egerton Coll. 

28592. Nearly similar specimen ; Eyeford, Gloucestershire. 

Purchased, 1853. 

32545. Right mandibular tooth, forming the type specimen of 
I. tessoni, Agassiz, torn. cit. ; Caen, Normandy. 

Tesson Coll. 

41307. Two imperfect pairs of mandibular teeth ; Caen. 

Purchased, 1869. 

44830. Upper portion of small right mandibular tooth ; Caen. 

Presented by Benjamin Bright, Esq., 1873. 



Ischyodus egertoni (Buckland). 

1835. CMirmra egertonii, W. Buckland, Proc. Geol Soc. vol. ii. p. 206. 

1836. Chimcera egertonii, W. Buckland, Phil. Mag. [3] vol. viii. p. 5. 
1843. Ischyodus egertoni, Sir P. Egerton, Proc. Geol. Soc. vol. iv. 

p. 156. 
1843. Chimcsra {Ischyodon) egertoni, L. Agassiz, Poiss. Foss. vol. iii. 

p. 340, pi. xl. c. figs. 1-10. 
1871. Ischyodus egertoni, J. Phillips, Geol. Oxford, p. 306, pi. xii. 

fig. 24. 

Type. Mandibular tooth, and the theoretically associated palatine 
and vomerine teeth • Oxford Museum. 

Mandibular tooth with a deeply sinuous oral margin, acute emi- 
nences corresponding to the beak and outer tritors, and the post- 
oral margin nearly parallel to the symphysial ; beak-tritor narrow 
and elongated antero- posteriorly ; outer tritors well developed ; 
median tritor broad, and occupying the greater portion of the 



62 CHIM^EROIDET. 

oral surface below and behind the apex of the anterior outer tritor. 
(?) Palatine tooth with the posterior inner tritor of large size, and the 
median tritor extending further forwards than this ; outer tritor 
much elongated and extending far forwards. (?) Vomerine tooth of 
the typical quadrate outline, with about six uniform tritors upon the 
oral margin. 

Form. Sf Loc. Oxford Clay : Oxfordshire and Northamptonshire. 
Kimmeridge Clay : Oxfordshire and Dorsetshire. 

P. 476. Left mandibular tooth, right palatine, and right and left 
vomerine teeth, described and figured by Agassiz, torn. cit. ; 
Kimmeridge Clay, Shotover, near Oxford. Egerton Coll. 

41173, 41226, 41395, 41863-4, 41961. Three mandibular teeth, 

and two pairs of small mandibular teeth ; Kimmeridge 
Clay, Weymouth. Purchased, 1868-70. 

P. 1159 a. Small left mandibular tooth ; Kimmeridge. 

Egerton Coll. 

P. 3094. Three mandibular teeth ; Weymouth. 

EnnisTciUen Coll. 

41174, 41225, 41397. Left palatine tooth, and two imperfect ex- 

amples of the right side ; Weymouth. Purchased, 1868-69. 

P. 3093 a. Imperfect left palatine tooth ; Weymouth. 

EnnisTciUen Coll. 

41396, 41962. Imperfect right vomerine tooth, and a pair of larger, 
but similar teeth ; Weymouth. Purchased, 1869-70. 

41865. Mandibular tooth of young ; Weymouth. Purchased, 1870. 

Ischyodus dufrenoyi, Egerton. 

1843. Cliimcera dufrenoyi, Sir P. Egerton, Proc. Geol. Soc. vol. iv. 

p. loo. 
1843. Ischyodus duvernoyi, Sir P. Egerton, ibid. p. 156 (errore). 
1867. Ischyodus dufrenoyi,!!. E. Sauvage, Catal. Poiss. Form. Second. 

-Boulonnais (Mem. Soc. Acad. Boulogne, vol. ii.), p. 73, pi. iv. 

fig. 12. 

Type. Left mandibular tooth. 

Mandibular tooth much compressed, with a deeply sinuous oral 
margin, a prominent symphysial beak, and the post-oral margin 
much more inclined backwards than the symphysial margin, which 
is gently arched; beak-tritor veif small; outer tritors well 
developed ; median tritor occupying the greater portion of the oral 



CH1.U.K1UD.K. 63 

surface below and behind the apex of the anterior outer tritor. 
'?) Palatine tooth with the posterior inner tritor of large size, and the 
median tritor not extending further forwards than this ; outer tritor 
much elongated and extending far forwards. 

Form. Sf Loc. Kimmeridge Clay : Boulogne, N. France. 

32416. Left mandibular tooth, probably referred to by Sauvage, 
op. cit. p. 74. Purchased, 1857. 

32767. More imperfect large specimen, of the right side. 

Purchased, 1857. 

32768. Right palatine tooth. Purchased, 1857. 



Ischyodus beaumonti, Egerton. 

1843. Chimcera {Ischyodus) beaumonti, Sir P. Egerton, Proc. Geol. 

Soc. vol. iv. pp. 155, 156. 
1843. Chimcera (Ischyodon) beaumontii, L. Agassiz, Poiss. Foss. vol. iii. 

p. 346. 
1847. Ischyodus, Sir P. Egerton, Quart. Journ. Geol. Soc. vol. iii. 

p. 351, pi. xiii. fig. 1. 

1866. Ischyodus beaumontii, E. T. Hamy, Bull. Soc. Geol. France, [2] 
vol. xxiii. p. 655, woodc. fig. 1. 

1867. Ischyodus beaumontii, H. E. Sauvage, Catal. Poiss. Form. 
Second. Boulonnais (Mem. Soc. Acad. Boulogne, vol. ii.), p. 83, 
pi. iv. figs. 4, 5. 

(?) 1867. Ischyodus rigauxi, H. E. Sauvage, ibid. p. 76, pi. iv. figs. 14, 

15. [Mandibular tooth ; Boulogne Museum.] 
1890. Ischyodus beaumonti, Woodward & Sherborn, Cat. Brit. Foss. 

Vertebrata, p. 105. 

Type. Eight palatine tooth. 

(?) Mandibular tooth with a very gently wavy oral margin, a 
short post-oral margin nearly parallel to the symphysial, and the 
beak more or less produced and acute ; beak-tritor small, elongated 
antero-posteriorly, with one or two minute tritors immediately 
within ; both outer tritors present, though small ; median tritor 
very large and broad, occupying the greater portion of the oral as- 
pect and nearer the post-oral than the symphysial margin. Pala- 
tine tooth with the posterior inner tritor of large size, and the median 
tritor not extending so far forwards as this ; outer tritor somewhat 
elongated. (?) Vomerine tooth relatively deep, with a series of small 
tritors. 

The mandibular tooth assigned to this species is described by 
Sauvage under the name of /. rigaucci. 

Form. Sf Loc. Eammeridge Clay : N. France and Dorsetshire. 



64 CHIM^EROIDEI. 

43023, 43283. Right and left palatine teeth, probably of a single 
individual ; Weymouth. Purchased, 187 j . 

41224, 41959, 42362. One imperfect and two complete smaller 
palatine teeth ; Weymouth. Purchased, 1868-70. 

P. 3093. A still smaller left palatine tooth, and two very small 
examples ; Weymouth. Enniskillen Coll. 

41396, 43557. Two right vomerine teeth ; Weymouth. 

Purchased, 1869, 1872. 

P. 1159. Imperfect left palatine and two right mandibular teeth ; 
Kimnieridge. Egerton Coll. 

32417. Left mandibular tooth, mentioned under the name of 
7". rigauxi by H. E. Sauvage, op. cit. p. 79 ; Boulogne. 

Purchased, 1857. 

41960, 42363, 43024, 43282. Three pairs of mandibular teeth ; 
Weymouth. Purchased, 1868-72. 

41172, 41394, 43556. Three mandibular teeth, one being of the 
right, and two of the left side ; Weymouth. 

Purchased, 1868-72. 

P. 6163. Pair of mandibular teeth, the left figured in Damon's Geol. 
Weymouth, Suppl. pi. xii. fig. 4 ; Weymouth. 

Purchased, 1890. 

Ischyodus townsendi (Buckland). 

1835. Chimcera townsendii, W. Buckland, Proc. Geol. Soc. vol. ii. 
p. 206. 

1836. Chimcera townsendii, W. Buckland, Phil. Mag. [3] vol. viii. 
p. 5. 

1843. Ischyodus townshendi, Sir P. Egerton, Proc. Geol. Soc. vol. iv. 

p. 156. 
1843. Chimcera (IscJiyodon) townsendii, L. Agassiz, Poiss. Foss. vol. iii. 

p. 343, pi. xl. figs. 20-22, pi. xl. c, figs. 17, 18. 
1878. Ischyodus townsendii, E. T.Newton, Ckimaeroid Fishes Brit. Cret. 

Rocks (Mem. Geol. Surv., Monogr. iv.), p. 33, pi. xi. 
1881. Ischyodus townsendii, E. T. Xewton, Proc. Geol. Assoc, vol. vii. 

p. 116, woodc. 

Type. Mandibular and theoretically associated vomerine teeth ; 
British Museum. 

The type species of very large size, the measurement from 
the symphysial border to the extremity of the post-oral margin of 
the mandibular tooth being sometimes 0*14. Mandibular tooth with 



CHOfJERIT)^. 65 

a gently wavy oral margin, a short post-oral margin nearly parallel 
to the symphysial, and the beak prominent ; beak-tritor divided into 
a series of small separate tritors ; anterior outer tritor relatively 
small, divided into two or more portions ; posterior tritor absent ; 
median tritor large, occupying the middle of the tooth, immediately 
below and in advance of the anterior outer tritor. Palatine tooth 
with the posterior inner and median tritors very large, and the 
outer tritor divided into a short series. Vomerine tooth with a series 
of five or six tritors, the inner being larger than the others. 

Form. Sf Loc. Portland] an : Oxfordshire, Wiltshire, and Dorset- 
shire. (Derived fossils in Neocomian Bone-beds of Bedfordshire and 
Cambridgeshire.) 

P. 474. Left mandibular tooth figured by Agassiz, torn. cit. pi. xl. 
tig. 20, to be regarded as the type specimen : Great Milton, 
near Oxford. Egerton Coll. 

P. 3095, P. 3095 a. More imperfect right mandibular tooth and 
fragment ; Great Milton. Ennishillen Coll. 

P. 1136, P. 4450. Fragments of mandibular teeth ; Great Haseley, 
near Oxford. Egerton Sf Ennishillen Colls. 

46400. Imperfect right mandibular tooth, noticed by E. T. Newton, 
op. cit. p. 36 ; Swindon, Wiltshire. Cunnington Coll. 

P. 6033. Right mandibular tooth ; Portland. 

Presented by George Clifton, Esq., 1889. 

40476. Much abraded right mandibular tooth, figured by E. T. 
Newton, op. cit. pi. xi. fig. 2; Neocomian Bone-bed, 
Potton, Bedfordshire. Purchased, 1867. 

P. 3096. Fragments of mandibular teeth : Potton. 

Ennishillen Coll. 

P. 6032. Associated fragments of teeth ; Portland. 

Presented by George Clifton, Esq., 1889. 

P. 409. Left palatine tooth; Portland. 

Presented by William Davies, Esq., 1881. 

P. 1135. Bight vomerine tooth, noticed by Agassiz, torn. cit. 
p. 344, and by E. T. Newton, op. cit. , p p. 36 ; Garsington, 
near Oxford. Egerton Coll. 

P. 3096 a. Left vomerine tooth ; Potton. Ennishillen Coll. 

PAET II. F 



f)6 CHIMJEROTDEI. 

Ischyodus quenstedti, Wagner. 

1857. Chimcera (Ischyodon) quenstedti, A. Wagner, Gelelir. Anz. k. bay. 

Akad. vol. xliv. p. 288. 
1862. Chimcera {Ischyodon) quenstedti, A. Wagner, Abh. math.-phys. 

CI. k. bay. Akad. Wiss. vol. ix. p. 280, pi. i. %. 1. 
1887. Ischyodus quenstedti, J. Riess, Palaeontogr. vol. xxxiv. p. 6, pi. i. 

figs. 1-5, pi. ii. figs. 1-7. 

Type. Greater portion of skeleton ; Palaeontological Museum, 
Munich. 

A species almost equalling i". toivnsendi in size, the trunk attaining 
a total length of 1'5. Mandibular tooth with a gently wavy oral 
margin, a short post-oral margin almost parallel to the symphysial, 
and the beak short ; anterior and posterior outer tritors small, 
undivided ; median tritor large, extending backwards from a point 
in advance of the anterior outer tritor, and only separated from the 
posterior outer tritor by a very narrow space. Palatine tooth with 
each of the tritors well developed, except the median, which is very 
small ; none subdivided. 

Form. Sf Loc. Lower Kimmeridgian (Lithographic Stone) : 
Bavaria. 

38005. Plaster cast of dorsal fin-spine of the type specimen, de- 
scribed and figured by Wagner, Abh. math.-phys. CI. k. 
bay. Akad. Wiss. vol. ix. pi. i. fig. 1 ; Eichstadt. 

Purchased, 1864. 

37021. Remains of the head and anterior portion of the trunk of a 
male individual of moderate size, preserved in counterpart 
slabs, and displaying the dentition, frontal spine, and 
dorsal fin-spine ; Solenhofen. The teeth are considerably 
crushed and not one satisfactorily exhibits the oral aspect. 
The frontal spine is also crushed, but evidently large, 
broad, widening proximally, and provided in the distal 
half with a tuft of recurved, subulate denticles. The 
dorsal spine resembles that already figured by Wagner. 

Hdberlein Coll. 

Ischyodus avitus (Meyer). 

1&60. Chimcera (Ganodus) prisca, H. von Meyer, Neues Jahrb. p. 212 

(name subsequently withdrawn) . 
1862. Chimcera (Ganodus) avita, H. von Meyer, Palaeontogr. vol. x. 

p. 87, pi. xii. 
1887. Ischyodus avita, J. Riess} Palaeontogr. vol. xxxiv. p. 14, pi. i. 

figs. 6, 7, pi. ii. fig. 8. 



UIllSLaSlUDJE. B7 

Type. Skeleton ; Paheontological Museum, Muuich. 

A species known only by a small skeleton, which exhibits the 
outer lateral aspect of the dentition. Head occupying somewhat 
less than one-quarter of the total length ; tail rapidly tapering. 
Space between pectoral and pelvic fins about equal to the distance of 
the former from the end of the snout. Dorsal fin-spine compara- 
tively short and robust, its length about equal to the depth of the 
trunk at its point of insertion. Oral margin of mandibular tooth 
regularly and deeply sinuous ; post-oral margin nearly parallel with 
the symphysial margin. 

Form. $• Loc. Lower Kimmeridgian (Lithographic Stone) : 
Bavaria. 

Not represented in the Collection. 

Ischyodus planus, Newton. 

1878. Ischyodus planus, E. T. Newton, Chirnseroid Fishes Brit. Cret. 
Rocks (Mem. Geol. Surv.), p. 37, pi. xii. figs. 1, 2. 

Type. Mandibular tooth ; collection of Thomas Jesson, Esq. 

A species of large size, known only by the mandibular teeth. 
Mandibular tooth with a gently wavy oral margin (and beak pro- 
bably short) ; beak-tritor single, laminated ; outer tritors rudimen- 
tary ; median tritor large, occupying nearly half of the oral surface, 
and posteriorly situated. 

Form. Sf Loc. Cambridge Greensand : Cambridge. (?) Upper 
Chalk: Norfolk. 

48945. Fragment of mandibular tooth, doubtfully assigned to this 
species by Newton, op. cit. p. 38 ; U. Chalk, Norwich. 

Bayfield Coll. 

Ischyodus thurmanni, Pictet & Campiche. 

1843. Ischyodus brevirostris, Sir P. Egerton, Proc. Geol. Soc. vol. iv. 

p. 156 (name only). 
1843. Chimcera (Ischyodon) brevirostris, L. Agassiz, Poiss. Foss. vol. hi. 

p. 344 (name only). 
1843. Chimcera (Ischyodon) agassizii, L. Agassiz (errore), ibid. pi. xl. c. 

figs. 14, 15. 
1858. Ischyodon thurmanni, Pictet & Campiche, Foss. Terr. Cretace 

St.-Croix (Pal. Suisse), p. 76, pi. ix. fig. 8. 
1862. Ischyodus agassizii, W. H. Bensted (errore), Geologist, vol. v. 

p. 378. 
1867. Ischyodus bouchardi, H. E. Sauvage, Catal. Poiss. Second. Bou- 

lomiais (Mem. Soc. Acad. Boulogne-sur-Mer. vol. ii.), p. 81, pi. iv. 

fig. 6. [Mandibular tooth.] 

f2 



68 CHTMJEROTDEI. 

1870. Ischyodus brevirostris, E. T. Newton, Quart. Journ. Geol. Soc. 

vol. xxxii. p. 326, pi. xxi. fig. o. [Teeth; British Museum.] 
1878. Ischyodus brevirostris, E. T. Newton, Chinneroid Fishes Brit. 

Cret. Rocks (Mem. Geol. Surv.), p. 27, pi. ix. 
1888. Ischyodus brevirostris, J. W. Davis, Trans. Roy. Dublin Soc. [2] 

vol. iv. p. 42, pi. vii. figs. 10-13. 

Type. Imperfect palatine tooth. 

Mandibular tooth notably robust, with a deeply sinuous oral 
margin, acute eminences corresponding to the outer tritors, and 
the beak prominent ; post-oral margin much less vertically inclined 
than the symphysial margin ; beak-tritor minute ; outer tritors well- 
developed ; median tritor narrow or of moderate width, occupying 
the greater portion of the oral surface immediately behind the 
anterior outer tritor. Palatine tooth with the posterior inner tritor 
of moderate or large size, and the median tritor not extending so 
far forwards as this ; outer tritor much elongated. Vomerine tooth 
much deeper at the symphysis than externally. 

Form. 6f Loc. Lower Greensand : Kent. Albian : Kent, England, 
and St.-Croix, Switzerland. Cenomanian and Turonian : Cambridge- 
shire and Kent. Greensand : Amuri Bluff, New Zealand {Newton 
and Davis). 

(i.) Lower Greensand, Maidstone. 

41682 a. Elongated right mandibular tooth, described and figured 
by E. T. Newton, op. cit. p. 31, pi. ix. fig. 10. 

Toulmin-Smith Coll. 

P. 1155. Fragmentary left mandibular tooth, noticed by E. T. New- 
ton, op. cit. p. 28. Egerton Coll. 

P. 3091-2. Two imperfect mandibular teeth. Ennishillen Coll. 

P. 475. Right palatine tooth, assigned to " Chimcsra (Ischyodon) 
agassizii " by Agassiz, torn. cit. pi. xl. c. figs. 14, 15. 

Egerton Coll. 

(ii.) Gault, Folkestone. 

47173 a, 47177. Right mandibular tooth and a pair, the former 
and one of the latter being figured by E. T. Newton, 
op. cit. pi. ix. figs. 3-5. Gardner Coll. 

47175, 47178, P. 27, P. 28. Four pairs of mandibular teeth. 

Gardner Coll. 

47173-74, P. 29. Six mandibular ^teeth, three of each side. 

Gardner Coll. 



cniM^itiDiE. 69 

P. 32, P. 33. Two very small mandibular teeth. Gardner Coll. 

35869. 43076, 43083. Three mandibular teeth. 

Purchased, 1861, 1871. 

P. 3086. Portion of right mandibular tooth labelled by Agassiz 
" Ohimcera brevirostris, Agass.,' 1 and intended to become 
the type specimen of the species thus named in MS. The 
fragment is figured by E. T. Newton, op. cit. pi. ix. figs. 
1, 2. Ennislcillen Coll. 

P. 26. Left mandibular tooth, associated with the left palatine. 

Gardner Coll. 

47176. Associated right and left palatine, and right vomerine tooth, 
figured by E. T. Newton, op. cit. pi. ix. figs. 13, 14, 20. 

Gardner Coll. 

47179, 46843. Two left palatine teeth, the oral aspect of the 
first being figured by E. T. Newton, op. cit. pi. ix. fig. 15. 

Gardner Coll. 

36910. Right palatine tooth. Purchased, 1863. 

(iii.) Cambridge Greensand, Cambridge. 
35147-50, 35160, 35373. Eight mandibular teeth, more or less 
fragmentary. Purchased, 1859. 

P. 1140. Two left mandibular teeth. Egerton Coll. 

35140. Right palatine tooth. Purchased, 1859. 

P. 1139. Three palatine teeth. Egerton Coll. 

P. 3087. Three palatine teeth, one being very imperfect. 

Enniskillen Coll. 

39101. Right vomerine tooth, figured by E. T. Newton, op. cit. 
pi. ix. fig. 21. Bowerbank Coll. 

35152-3,35450. Three vomerine teeth. Purchased, 1859. 

P. 1141. Right vomerine tooth. Egerton Coll. 

(iv.) Lower Chalk, Burham, Kent. 
49019. Right palatine tooth, probably of this species. 

Mrs. Smith's Coll. 

(v.) Greensand, Amuri Bluff, New Zealand. 
P. 2302. Right mandibular tooth, assigned to this species by E. T. 
Newton, Quart. Journ. Geol. Soc. vol. xxxii. p. 326, 
pi. xxi. fig. 5. By exchange, 1876. 



70 CTTm^ROIDET. 

Ischyodus latus, Newton. 

1878. Ischyodus latus, E. T. Newton, Chimaeroid Fishes Brit. Cret. 
Rocks (Mem. Geol. Surv.), p. 32, pi. x. figs. 1-3 (Pfigs. 4-] 2). 

Type. Mandibular tooth ; Museum of Practical Geology. 

Mandibular tooth closely resembling that of I. thurmanni, but the 
median tritor very broad and extending forwards to the symphysis. 
Supposed palatine tooth with very broad tritors covering nearly the 
whole of the oral surface, the outer tritor being narrow, and the 
median extending further forwards than the posterior inner tritor. 

Form. Sf Log. Cambridge Greensand : Cambridge. 

Not represented in the Collection. 

Ischyodus (?) incisus, Newton. 
1878. Ischyodus incisus, E. T. Newton, op. cit. p. 38, pi. xii. figs. 3-10. 

Type. Left mandibular tooth ; British Museum. 

A small species of doubtful generic position, the mandibular tooth 
apparently not attaining a greater antero-posterior measurement 
than , 035-0*04. Mandibular tooth much compressed, with a deeply 
sinuous oral margin, acute eminences corresponding to the outer 
tritors, and the beak prominent ; post-oral margin partly parallel 
with the symphysial margin ; beak-tritor subdivided into a short 
series ; anterior outer tritor small and narrow, the posterior one 
represented by a marginal series of minute tritors ; median tritor 
very narrow and insignificant. [Palatine tooth unknown.] (?) Vo- 
merine tooth relatively broad, prominently convex externally. 

Form. Sf Log. Albian : Kent. Cenomanian : Cambridgeshire. 
Turonian : Kent and Sussex. 

41683. Left mandibular tooth, being the type specimen figured by 
Newton, op. cit. pi. xii. figs. 3-5 ; Lower Chalk, (?) Kent. 

Toulmin-Smith Coll. 

47942-3. Left mandibular and vomerine teeth, figured by Newton, 
op. cit. pi. xii. figs. 6-8 ; Lower Chalk, Burham, Kent. 

Presented by the Hon. Robert Marsham, 1877. 

The following dorsal fin-spines are of the form named Leptacan- 
thus by Agassiz, Aiduxacanthus by Sauvage, and Chimceracanthus by 
Quenstedt, and probably all pertain to species of Ischyodus : — 

32728-30. Three imperfect spines of the form named Leptacanthus 
longissimus, Agassiz 1 , and probably referable to Ischyodus 
emarginatus ; Great Oolite, Caen, Normandy. Tesson Cull. 

1 Poiss. Foss. vol. iii. (1837), p. 29, pi. i. a. figs. 14-18. 



71 

ClllM/KKID.K ' x 

P. 2214. Fragment of a similar spine ; Caen. Egerton Coll. 

27412. Small slender spine 0-059 in length ; Oxford Clay, Christian 

Malford, Wiltshire. Purchased, 1852. 

41877. Portion of large spine ; Kimmeridge Clay, Weymouth. 

Purchased, 1869. 

43558. Proximal half of large spine; Weymouth. Purchased, 185 r 2. 

P. 1159, P. 3098. Two portions of similar spines; Weymouth. 

Egerton fy EiinisJcillen Colls. 

36162-3. Large portions of two spines of the form named Auluxa- 
canthus dutertrei, H. E. Sauvage, Catal. Poiss. Form. 
Second. Boulonnais (Mem. Soc. Acad. Boulogne, vol. ii. 
1867), p. 65, pi. iii. fig. 1 ; Kimmeridge Clay, Boulogne- 
sur-Mer. Purchased, 1861. 

P. 6036. Fragment ; Portland Stone, Weymouth. 

Presented by George Clifton, Esq., 1889. 

47187, P. 34, P. 60. Four fragments and one nearly complete spine, 
prohably of Ischyodus thurmanni ; Gault, Folkestone. 

Gardner Coll. 

The fragment of spine named Chimcer 'acanthus aalensis by Q,uen- 
stedt (Der Jura, 1858, p. 347, pi. xlvii. fig. 19) was obtained from the 
Brown Jura ft of Wurternberg, and is now preserved in the Tubingen 
University Museum. 

Another spine, from the Upper Trias of Lombardy, said to be of 
the same type as those mentioned above, is described under the 
name of Lejptacanthus cornalia;, C. Bellotti in A. Stoppani's Studii 
Geol. e Paleont. Lombardia (1858), p. 437. This, however, is 
evidently Hybodont, as pointed out by E. Cornalia, Giorn. B. Istit. 
Lombardo, vol. vi. (1854), p. 58, pi. ii. fig. 5. 

The following species have also been founded upon detached 
teeth, of which there are no representatives in the Collection : — 

Ischyodus aalensis, J. Biess, Palaeontogr. vol. xxxiv. (1887), p. 19, 
pi. i. fig. 9 : Chimcera aalensis, F. A. Quenstedt, Handb. 
Petrefakt. (1852), p. 185, pi. xiv. figs. 14-16, and Der 
Jura (1858), pp. 339, 347, pi. xlvii. figs. 21-28.— 
Brown Jura ft ; Wiirtemberg. [Tubingen University 
Museum.] 

acutus, H. von Meyer, Paiaeontogr. vol. vii. (1859), 
p. 17, pi. ii. figs. 9-12. — Portlandian ; Hanover. [Left 
vomerine tooth.] 



72 CHIMjEROIDEI. 

Ischyodus bcaugrandi, H. E. Sauvage, Catal. Poiss. Form. Second. 
Boulonnais (Mem. Soc. Acad. Boulogne-sur-Mer, vol. ii. 
1867), p. 79, pi. iv. figs. 7, 8.— Kimmeridgian ; Chatillon, 
Boulogne. [Mandibular tooth.] 

Ischyodus bifurcati : Chimcera bifurcati, F. A. Quenstedt, Handb. 
Palaeont. ed. 3 (1883), p. 293, pi. xxiii. fig. 25 ; J". Biess, 
Paleeontogr. vol. xxxiv. (1887), p. 19. — Brown Jura 2 ; 
Wiirtemberg. [Fragmentary mandibular tooth (? = 1. 
adlensis) ; Tubingen University Museum.] 

Ischyodus dutertrei, Sir P. Egerton, Proc. Geol. Soc. vol. iv. (1843), 
p. 156 (dutetrii) ; H. E. Sauvage, op. cit. p. 89, pi. iii. 
figs. 17-19 : Chimcera dutetrii, Sir P. Egerton, Ann. Mag. 
Nat. Hist. vol. xii. (1843), p. 469, and Proc. Geol. Soc. 
vol. iv. (1843), p. 154 : Chimcera (Ischyodon) dutertrii, 
L. Agassiz, Poiss. Foss. vol. iii. (1843), p. 345. — Port- 
landian ; Boulogne. [Mandibular tooth.] 

Ischyodus ferrugineus, J. Biess, Palaeontogr. vol. xxxiv. (1887), 
p. 20, pi. i. fig. 10, pi. iii. fig. 11. — Brown Jura /3 ; Aalen, 
Wiirtemberg. [Mandibular tooth ; Munich Museum.] 

Ischyodus personati : Chimcera personati, F. A. Quenstedt, Handb. 
Petrefakt. ed. 1 (1852), p. 185, pi. xiv. fig. 17, and Der 
Jura (1858), p. 339, pi. xlvi. figs. 8, 9.— Brown Jura /3 : 
Wiirtemberg. [Fragmentary teeth : Tubingen University 
Museum.] 

Ischyodus sauvagei, E. T. Hamy, Bull. Soc. Geol. France, [2] 
vol. xxiii. (1866), p. 655, woodc. fig. 2 ; H. E. Sauvage, 
Catal. Poiss. Form. Second. Boulonnais (Mem. Soc. Acad. 
Boulogne-sur-Mer, vol. ii. 1867), p. 86, pi. iv. figs. 2, 3.— 
Kimmeridgian ; Boulogne. [Palatine tooth ; Boulogne 
Museum.] 

Ischyodus schuebleri, J. Biess, Paleeontogr. vol. xxxiv. (1887), 
p. 1 7, pi. i. fig. 8 : Chimcera schuebleri, F. A. Quenstedt, 
Der Jura (1858), p. 782, pi. xcvi. fig. 39: Ischyodus 
{Chimcera) rostratus, H. von Meyer, Palaeontogr. vol. vii. 
(1859), p. 14, pi. ii. figs. 3-8.— White Jura e ; Wiirtem- 
berg and Bavaria. Portlandian ; Hanover. [Mandibular 
tooth ; Tubingen University Museum.] 

Ischyodus suprajurensis, H. E. Sauvage, op. cit. p. 75, pi. iv. fig. 13. 
— Kimmeridgian ; Boulogne. [Imperfect mandibular 
tooth (? of Ischyodus beaumonti) ; Boulogne Museum.] 

A Chimseroid egg from the Jurassic of Wiirtemberg, not impro- 
bably referable to Ischyodus, has also been described by E. Bessels, 
Wiirtt.Mahresh. vol. xxv. (1869), p. 152, pi. iii. 



cwimmridm, 73 



Genus EDAPHODON, Auckland. 

[Proc. Geol. Soc. vol. ii. 1838, p. 687 \] 

Syn. Passalodon, W. Buckland, ibid. 

Psittacodon, L. Agassiz, Poiss. Foss. vol. iii. 1843, p. 340 (in 

part). 
Eumylodus, J. Leidy, Extinct Vert. Fauna W. Territ. (Rep. U. S. 

Geol. Surv. Territ. vol. i. 1873), p. 309. 
Dipristis, 0. C. Marsh, Proc. Amer. Assoc. Adv. Sci. 1869, p. 230. 

Mandibular tooth massive, with no definite thickening upon the 
outer aspect, and the symphysial facette very broad ; one anterior 
tritor present, and sometimes a smaller one below it ; one median 
tritor, occasionally divided longitudinally, and two external tritors. 
Palatine teeth very robust, with no well-defined thickening upon 
the outer aspect ; three tritors present, two being inner and one 
outer. Vomerine tooth more or less triangular in side view, with 
tritors upon the oral margin ; post-oral region laterally expanded, 
without any thickening. 

The name of Passalodon was applied by Buckland to the vomerine 
teeth, and that of Psittacodon by Agassiz to the mandibular teeth 
of E. mantelli and E. sedgwicki. 

Edaphodon sedgwicki (Agassiz). 

1843. Chimcera {Psittacodon) sedgiuickii, L. Agassiz, Poiss. Foss. vol. 

iii. p. 349, pi. xl. figs. 17, 18. 
1843. Ischyodus sedgwicki, Sir P. Egerton, Proc. Geol. Soc. vol. iv. 

p. 156. 
1847. Edaphodon sedgwicki, Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. iii. p. 352. 
1850. Edaphodon sedgioicki, F. Dixon, Foss. Sussex, p. 203. 
1864. Edaphodus huxleyi, H. G. Seeley, Ann. Mag. Nat. Hist. [3] 

vol. xiv. p. 276 (name only). [Fragmentary teeth ; Woodwardian 

Museum, Cambridge.] 
1878. Edaphodon sedgioickii, E. T. Newton, Chirnaeroid Fishes Brit. 

Cret. Rocks (Mem. Geol. Surv., Monogr. iv.), p. 7, pis. i., ii. 

Type. Imperfect right mandibular tooth ; Mus. Geological Society 
of London. 

A species attaining to a very large size, the measurement from 
the middle of the symphysial border to the extremity of the post- 
oral margin of the mandibular tooth being sometimes 0*15. Man- 
dibular tooth with a very prominent beak, and the symphysial 

1 This genus was first satisfactorily defined by Egerton, Quart. Journ. Geol, 
Soc. vol. iii. (18^7), p. 351, pi. xiii. figs. 2, 3. 



7-4 CHIM^EROIPET. 

facette occupying at least one third of the inner aspect ; beak-tritor 
composed of a series of laminae, the other tritors consisting of 
numerous tubules ; median tritor divided [in unabraded specimens] 
into two small, widely- separated parts, of which the anterior is 
placed upon the edge of the symphysis, and the posterior behind 
the anterior outer tritor. Palatine tooth with very large tritors, the 
two inner being broad, and the posterior of these tending to overlap 
the narrow outer tritor. Vomerine tooth with a concave or grooved 
symphysial surface ; the anterior tritor much larger than the 
others. 

A specimen obtained by Mr. Charles Potter from the Chalk of 
Lewes, and described by Newton, op. cit., makes known the com- 
plete dentition of this species. 

Form. $• Loc. Neocomian : Isle of Wight. Albian : Kent. Ceno- 
manian : Cambridgeshire, Norfolk, and Kent. Turonian : Kent 
and Sussex. (?) Senonian : Norfolk. 

(i.) Gault, Folkestone. 

P. 23. Pair of mandibular teeth with very long beak. 

Gardner Coll. 

47183, P. 24. Two right mandibular teeth, one being imperfect. 

Gardner Coll. 

43604, Left mandibular tooth. Purchased, 1859. 

P. 25. Pair of palatine teeth. Gardner Coll. 

(ii.) Cambridge Greensand, Cambridge. 
30252. Left mandibular tooth of moderate size. Purchased, 1855. 

35136. Very robust, large right mandibular tooth. 

Purchased, 1859. 

35399, 35400. Eight and left mandibular teeth. Purchased, 1860. 

47955-6. Two fragmentary mandibular teeth. 

Presented by the Hon. Robert Marsham, 1877. 

P. 1144. Portion of a very large right mandibular tooth. 

Egerton Coll. 

P. 3083-4. Small right mandibular tooth, and one of the left side 
very small. EnnisTcillen Coll. 

P. 6004. Mandibular teeth, associated with the vomerine and palatine 
teeth of the right side v Purchased, 1889. 

35134, 35137. Three imperfect palatine teeth. Purchased, 1859. 



CHTMJTRTPiE. 75 

35401-2. Right and left palatine teeth. Purchased, 1860. 

P. 1142. Left palatine tooth. Egerton Coll. 

P. 3081. Right palatine tooth, and two imperfect specimens. 

Enniskillen Coll. 

35132-3, 35151, 35370. Four vomerine teeth. Purchased, 1859. 

39099, 39100. Right and left vomerine teeth. Bowerbank Coll. 

46357-8. Left vomerine tooth and a small example of the right 
side. Cunnington Coll. 

P. 1143. Two imperfect right vomerine teeth. Egerton Coll. 

P. 3082. Three imperfect left vomerine teeth. EnnisJcillen Coll. 

(iii.) Red Chalk, Hunstanton. 

P. 4965. Very imperfect right vomerine tooth, doubtfully of this 
species. Presented by J. E. Lee, Esq., 1885. 

(iv.) Chalk Marl, Dover. 

47184-5. Two small right mandibular teeth, probably of this species. 

Gardner Coll. 

(v.) Upper Chalk, Norwich. 
48944. Fragments of the dentition of one individual, including the 
nearly complete vomerine teeth, doubtfully assigned to 
this species by Newton, op. cit. p. 11. Bayfield Coll. 

P. 414. A pair of mandibular teeth, the right vomerine, and frag- 
ments of the palatines, found associated and resembling 
the foregoing, though smaller. 

Presented by S. T. Bayfield, Esq., 1881. 

(vi.) Chalk, Sussex. 

25746. Right mandibular tooth, probably of this species. s 

Diccon Coll. 

Edaphodon mantelli (Buckland). 

1835. Chimcera mantellii, W. Buckland, Proc. Geol. Soc. vol. ii.p. 206. 

1836. Chimcera mantellii, W. Buckland, Phil. Mag. [3] vol. viii. p. 5. 
1843. Ischyodus mantelli, Sir P. Egerton, Proc. Geol. Soc. vol. iv. 

p. 156. 
1843. Chimcera (Psittacodon) mantellii,^. Agassiz, Poiss. Foss. vol. iii. 

p. 348, pi. xl. a. figs. 1, 2. 
1847. Edaphodon mantellii, Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. iii. p. 352. 



76 CHIM^KOIDEI. 

1850. Edaphodvn mantelli, F. Dixon, Foss. Sussex, p. 203, pi. xxxiv. 

figs. 6, 7. 
1875. Chimara mantellii, H. B. Geinitz, Palseontogr. vol. xx. pt. ii. 

p. 206, pi. xxxix. figs. 11, 12. 
1878. Edaphodon mantellii, E. T. Newton, Chimaeroid Fishes Brit. 

Cret. Rocks (Mem. Geol. Surv., Monogr. iv.), p. 14, pi. iv. figs. 1-9. 

Type. Mandibular teeth ; British Museum. 

A species not attaining so large a size as E. sedgwichi, but 
scarcely differing in the characters of the dentition. The mandi- 
bular tooth appears to be less robust than that of the latter species, 
and the tritors are often much narrower. In the palatine tooth 
also the posterior inner tritor is relatively longer and narrower. 

Form. Sf Log. Cenomanian, Turonian, and Senonian : Kent and 
Sussex. (?) Cenomanian : Cambridgeshire. Cenomanian : Saxony. 

4280-1. Type specimens figured by Agassiz and Newton ; Upper 
Chalk, Lewes, Sussex. Mantell Coll. 

49729. Small left mandibular tooth ; Lewes. Capron Coll. 

P. 3085. Slender left mandibular tooth ; Lewes. Enniskillen Coll. 

P. 5405. Larger and stouter example of the same tooth ; Lewes. 

Presented by P. E. Coombe, Esq., 1888. 

25891. Imperfect small right mandibular tooth ; Chalk, Sussex. 

Dixon Coll. 

49728. Small left mandibular tooth, figured by Newton, op. cit. 
pi. iv. fig. 9 ; Upper Chalk, Houghton, Arundel, Sussex. 

Capron Coll. 

49724. Stouter example of the same tooth, doubtfully of this 
species ; Chalk, Brighton, Sussex. Capron Coll. 

25892. Portion of right mandibular tooth, figured by Dixon, op. cit. 

pi. xxxiv. fig. 7 ; Chalk, Sussex. Dixon Coll. 

49018. Pair of mandibular teeth ; English Chalk. Mrs. Smith's Coll. 

41676, 41679. Bight mandibular tooth noticed by Newton, op. cit. 
p. 16, and the anterior two thirds of a larger, more 
elongated, example of the left side ; Upper Chalk, Kent. 

Toulmin-Smith Coll. 

43128. Small right mandibular tooth ; Chalk, Kent. Wetherell Coll. 

49013. Imperfect right mandibular tooth, figured by Dixon, op. cit. 
pi. xxxiv. fig. 6 ; Kent. Mrs. Smith's Coll. 

P. 316. More imperfect similar A specimen, of the left side; Lower 
Chalk, Burham, Kent. Harris Coll. 



chuvlerid^. 77 

P. 317. Very small right mandibular tooth, doubtfully of this 
species ; Chalk, Hart Hill, Charing, Kent. Harris Coll. 

P. 5619. Right mandibular tooth ; Kent. Harford Coll. 

36903. Pair of imperfect mandibular teeth ; Grey Chalk, Dover. 

Purchased^ 1862. 

46359. Almost unabraded right mandibular tooth, probably of this 
species ; Cambridge Greensand. Cunnington Coll. 

41677, 41680. Left palatine tooth, and an imperfect pair of smaller 

palatine teeth j Chalk, Sussex. Toulmin-Smith Coll. 

25894. Very small right palatine tooth, labelled by Agassiz as per- 
taining to this species ; Sussex. Dixon Coll. 

25860. Eight vomerine tooth, probably of this species ; Sussex. 

Dixon Coll. 

49721. Small right palatine tooth, figured by Newton, op. cit. pi. iv. 

fig. 8, as probably referable to this species ; Upper Chalk, 
Guildford. Capron Coll. 

49722. Small right palatine tooth, doubtfully of this species, figured 

ibid. pi. iv. fig. 12 ; Lower Chalk, Glynde, Sussex. 

Capron Coll. 

Some large vomerine teeth from the Chalk of Sussex, probably 
pertaining to one of the two last- described species, are named 
Edaphodon gigas, Egerton \ The following specimens are of this 
character : — 

41678. Right vomerine tooth, figured by Newton, op. cit. pi. v. fig. 2 ; 

Chalk, Lewes. Toulmin-Smith Coll. 

P. 1146. Fragment of left vomerine tooth, labelled by Egerton ; 
Chalk, Sussex. Egerton Coll. 

Edaphodon agassizi (Buckland). 

1835. Chimcera agassizii, W. Buckland, Proc. Geol. Soc. vol. ii. p. 206. 

1836. Chimtera agassizii, W. Buckland, Phil. Mag. [3] vol. viii. p. 5. 
1843. Ischyodus agassizi, Sir P. Egerton, Proc. Geol. Soc. vol. iv. 

p. 156. 
1843. Chimcera (Ischyodon) agassizii, L. Agassiz, Poiss. Foss. vol. iii. 
p. 341, pi. xl. a. figs. 3, 4, (?5), pi. xl. c. fig. 16 {non figs. 14, 15). 

1 Quart. Journ. Geol. Soc. vol. iii. (1847), p. 352. Also E. T. Newton, Mem. 
G-eol. Surv., Monogr. iv. (1878), p. 17, pi. v. figs. 1, 2. — Ischyodus gigas, Eger- 
ton, Proc. Geol. Soc. vol. iv. (1843), p. 211 ; also F. Dixon, Foss. Sussex (1850), 
pi. xxxiv. fig 8. 



78 CHIMJ5R0IDEI. 

1S44. Chima-ra, G: A. Mantell, Medals of Creation, p. 621. 

L875. Chimera agassizii, H. B. Geinitz, Palaeontogr. vol. xx. pt. ii. 

p. 206, pi. xxxix. figs. 8-10. 
1878. Edaplwdon ayasshii, E. T. Newton, Chimseroid Fishes Brit. 

Cret. Rocks (Mem. Geol. Surv., Monogr. i\\), p. 12, pi. iii. 

Type. Imperfect mandibular tooth ; British Museum. 

Mandibular tooth comparatively short and robust, and the beak 
only slightly produced ; symphysial facette occupying less than one 
third of the inner aspect ; beak-tritor composed of a series of laminae, 
the other tritors consisting of a number of tubules : median tritor 
very broad, occupying the greater portion of the oral surface, and 
apparently exposed superiorly throughout its length. [Palatine and 
vomerine teeth unknown.] 

Form. <$f Loc. Cenomanian and Turonian : Sussex, Kent, and 
Surrey. Cenomanian : Saxony. 

28387. Type specimen, figured by Agassiz, torn. cit. pi. xl. a. figs. 3, 
4, and by Newton, op. cit. pi. iii. figs. 1, 2 ; Chalk Marl, 
Hamsey, Sussex. Mantell Coll. 

49723. Left mandibular tooth ; Lower Chalk, Southeram, near 
Lewes. C apron Coll. 

P. 5406. More imperfect example ; Lewes. 

Presented by P. E. Coombe, Esq., 1888. 

28386. Pair of mandibular teeth, associated with dorsal fin-spine, 
noticed by Mantell (op. cit.), and figured by Newton, 
op. cit. pi. iii. fig. 3 ; Lower Chalk, Burham, Kent. 

Mantell Coll. 

P. 1154. Imperfect small right mandibular tooth, the symphysis 
either broken or unusually narrow ; Lower Chalk, Kent. 

Egerton Coll. 

41681. Imperfect left mandibular tooth, equally small; Dorking, 
Surrej*. Toulmin-Smith Coll. 

4283. Imperfect small left palatine tooth, assigned to this species 
by Agassiz (torn. cit. pi. xl. a. fig. 5), but stated by Newton 
(op. cit. p. 13) to be too imperfect for determination; 
Lewes. Mantell Coll. 

Edaphodon crassus, Newton. 

1878. Edaphodon crassus,~E. T. Newton, Chimaeroid Fishes Brit. Cret. 
Rocks (Mem. Geol. Surv., Monogr. iv.), p. 21, pi. vii. 

Type. Associated dentition ; Museum of Practical Geology. 

A species of small size. Mandibular tooth short and robust, and 






CHIM.ERID^E. 79 

the beak not very prominent ; syinpkysial facette occupying at least 
one third of the iuner aspect ; beak-tritor composed of a series of 
laminae, with a minute tubulated tritor immediately above it ; 
median tritor occupying the greater portion of the inner aspect, 
extending forwards to the symphysis and only slightly separated 
from the posterior outer tritor. Palatine tooth depressed, the oral 
surface almost covered by the tritors, of which the posterior inner 
one is especially broad. 

Form. Sf Log. Cenomanian : Cambridgeshire and Wiltshire. 
(?)Turonian: Sussex. 

35145-6. Two right mandibular teeth, somewhat imperfect ; Cam- 
bridge Greensand, Cambridge. Purchased, 1859. 

35343, 35429. Two imperfect palatine teeth, right and left ; Cam- 
bridge. Purchased, 1859. 

P. 1145. Two palatine teeth, right and left; Cambridge. 

Egerton Coll. 

P. 3088. Two more abraded palatine teeth, right and left ; Cam- 
bridge. Ennishillen Coll. 

Edaphodon reedi, Newton. 

1878. Edaphodon reedii, E. T. Newton, Chimeeroid Fishes Brit. Cret. 
Rocks (Mem. Geol. Surv., Monogr. iv.), p. 19, pi. vi. 

Type. Mandibular tooth, associated with palatine and vomerine 
teeth ; Reed Collection, York Museum. 

Mandibular tooth with a very prominent beak, and the symphysial 
facette occupying at least one third of the inner aspect ; beak-tritor 
composed of a series of laminae, the other tritors consisting of 
numerous tubules ; median tritor with only a minute representative 
upon the edge of the symphysis ; posterior outer tritor wanting. 
Palatine tooth with the posterior inner tritor very small or absent, 
and the outer smaller than the anterior inner tritor. 

Form. Sf Loc. Cenomanian : Cambridgeshire. 

35139. Small imperfect right mandibular tooth ; Cambridge Green- 
sand, Cambridge. Purchased, 1859. 
46356. Pair of palatine teeth, the left being imperfect ; Cambridge. 

Cunnington Coll. 
35138, 35141, 35160. Three small palatine teeth, somewhat im- 
perfect ; Cambridge. Purchased, 1859. 
49727. Right palatine tooth, regarded by Newton (o_p. cit. p. 21) as 
possibly of this species ; Chalk, Glynde, Sussex. 

Capron Coll. 



80 chimjEroidei. 

Edaphodon bucklandi, Agassiz. 

1843. Edaphodon bucklandi, L. Agassiz, Poiss. Foss. vol. iii. p. 351, 

pi. xl. d, figs. 1-4, 9-12, 19-24. 
1843. Edaphodon eurygnathus, L. Agassiz, ibid. p. 352. [Palatine 

teeth ; British Museum.] 
1850. Edaphodon eurygnathus, F. Dixon, Foss. Sussex, p. Ill, pi. x. 

figs. 18, 19, 22, pi. xii. fig. 5. 
1885. Edaphodon bucklandi, F. Noetling, Abh. geol. Specialk. Preussen 

u. Thuring. Staaten, vol. vi. pt. 3, p. 3, pi. i. fig. 1. 

Type. Theoretically associated dentition of both jaws ; British 
Museum (in part). 

The type species, of large size, the mandibular tooth sometimes 
measuring 0*11 from the middle of the symphysial border to the 
extremity of the post-oral margin. Mandibular tooth robust, with 
a prominent beak, and the symphysial facette occupying more than 
one third of the inner aspect ; beak-tritor mostly composed of 
laminae, the other tritors consisting of numerous tubules ; median 
tritor occupying more than two thirds of the inner oral surface, 
with a narrow band separated from it immediately upon the posterior 
border of the symphysis. Palatine tooth relatively broad, with 
large tritors, the posterior inner one being the largest and broadest 
and well separated from the outer tritor, which is much elongated 
and expands anteriorly. Vomerine tooth very robust, with a broad 
symphysial surface. 

The differences between the palatine and vomerine teeth of this 
species and those of the so-called E. eurygnathus are solely due to 
the imperfect state of preservation of the type specimens of the 
latter. 

Form. Sf Log. Middle Eocene (Bagshot and Bracklesham Beds) : 
Surrey and Sussex. Lower Eocene : Isle of Sheppey. Eocene 
(Zone A x ) : Samland, Prussia. 

25700. Left mandibular tooth ; London Clay, Sheppey. 

Dixon Coll. 
25719,25721. Two examples of the same tooth, one being more 

imperfect, the other nearly complete, but more slender; 

Bracklesham Beds, Bracklesham Bay, Sussex. Dixon Coll. 

P. 3074-5. Five mandibular teeth ; Bracklesham. EnnisMllen Coll . 

P. 5436. Left mandibular tooth ; Bracklesham. 

Presented by P. E. Coombe, Esq., 1888. 

38870. Bight palatine tooth, figured among the type specimens by 
Agassiz, torn. cit. pi. xl. d. figs. 19-24 ; Bracklesham {not 
Bagshot, as stated). Bowerbank Coll. 



cmummvm. 81 

25696. Pair of palatine teeth, forming the type specimen of E. 
eurygnaihus figured by Dixon, op. cit. pi. x. fig. 18 ; 
Bracklesham. Dixon Coll. 

25695. Left palatine tooth ; Bracklesham. Dixon Coll. 

28081. Left palatine tooth ; Bracklesham. 

Presented by F. E. Edwards, Esq., 1852. 

P. 1147. Inner portion of right palatine tooth ; Bracklesham. 

Egerton Coll. 

25673. Imperfect right vomerine tooth, figured by Dixon, op. cit. 
pi. x. fig. 19, under the name of E. eurygnaihus ; Brackles- 
ham. Dixon Coll. 

25727. Nearly perfect left vomerine tooth ; Bracklesham. 

Dixon Coll. 

38877. Similar specimen, though more abraded externally, figured 
by Dixon, op. cit. pi. xii. fig. 5, under the name of E. eury- 
gnaihus ; Bracklesham. Bowerbanlc Coll. 

38878-80. Similarly abraded right vomerine tooth, another scarcely 
abraded and stouter, and a fragment of one of the left 
side ; Bracklesham. Bowerbank Coll. 

P. 1149. Left vomerine tooth, much abraded externally ; Brackles- 
ham. Egerton Coll. 

Edaphodon leptognathus, Agassiz. 

1843. Edaphodon leptognathus, L. Agassiz, Poiss. Foss. vol. iii. p. 352, 

pi. xl. d. figs. 5-8, 13-18. 
1847. Edaphodon, Sir P. Egerton, Quart. Journ. Geol. Soc. vol. iii. 

p. 351, pi. xiii. figs. 2, 3. 
1850. Edaphodon leptognathus, P. Dixon, Foss. Sussex, p. Ill, pi. x. 

figs. 20, 21. 

Type. Theoretically associated mandibular and palatine teeth; 
British Museum (in part). 

A species closely related to E. bucklandi, but readily distinguished 
by the much greater slenderness of all the teeth. 

Form. 6f Loc. Middle Eocene (Bagshot and Bracklesham Beds) : 
Middlesex, Surrey, and Sussex. Upper Eocene (Barton Clay) : 
Hampshire. 

25699, 25723, 25725, 25730. Eight mandibular tooth figured by 
Dixon, op. cit. pi. x. fig. 21, and three other mandibular 
teeth ; Bracklesham. Dixon Coll. 

PART II. & 



82 CHIM.EROIDEI. 

24844. Left mandibular tooth ; Bracklesham. Purchased, 1850. 

28081 a. Similar specimen, wanting the extremity of the beak, and 
a right mandibular tooth ; Bracklesham. 

Presented by F. E. Edwards, Esq., 1852. 

38873. Left mandibular tooth ; Bracklesham. Bowerbank Coll. 

Fig. 8. 




Left mandibular tooth, inner aspect, of Edaphodon leptognathus, Ag. ; 
Bracklesham Beds. 

P. 1148. Two left mandibular teeth ; Bracklesham. Egerton Coll. 

P. 3077. Two small left mandibular teeth, and one of the right 
side ; Bracklesham. EnnisTcillen Coll. 

P. 5437. Small right mandibular tooth ; Bracklesham. 

Presented by P. E. Coombe, Esq., 1888. 

38871. Bight palatine tooth, figured as one of the type specimens 

by Agassiz, torn. cit. pi. xl. d. figs. 13-18 ; Goldsworthy 
Hill, Surrey. Bowerbank Coll. 

25698, 25720, 25722, 25730 a. Bight palatine tooth figured by 
Dixon, op. cit. pi. x. fig. 20, and three other palatine 
teeth ; Bracklesham. Dixon Coll. 

38872. Right palatine tooth ; Bracklesham. Bowerbank Coll. 

41299. Three imperfect palatine teeth ; Bracklesham. 

Purchased, 1869. 

P. 1150 a. Left palatine tooth ; Bracklesham. Egerton Coll. 

P. 3078. Fragmentary similar tooth, and two smaller right palatine 
teeth ; Bracklesham. Enniskillen Coll. 

P. 5434. Large right palatine tooth ; Bracklesham. 

Presented by P. E. Coombe, Esq., 1888. 

25732. Left vomerine tooth ; Bracklesham. Dixon Coll. 



CHIMJvRID^. 83 

P. 1150. Three small right palatine teeth ; Bracklesham. 

Eyerton Coll. 

P. 1151. Portion of a similar tooth ; Bracklesham. Egerton Coll. 

P. 5581. Imperfect right mandibular tooth, much abraded, probably 
of this species ; Red Crag (derived fossil), Woodbridge. 

Harford Coll. 

The following specimens may also, perhaps, pertain to this 
species : — 

P. 6226. Fragment of inner side of left palatine tooth ; Lower Bag- 
shot Beds, Hampstead, near London. 

Presented by Robert Maitland, Esq., 1884. 

P. 415. Left palatine tooth, with the tritors almost destroyed ; 
Thanet Sands, near Croydon, Surrey. 

Presented by H. Turner, Esq., 18S2. 

Edaphodon (?) laminosus, Newton. 

1878. Edaphodon laminosus, E. T. Newton, Ckimaeroid Fishes Brit. 
Cret. Rocks (Mem. Geol. Surv., Monogr. iv.), p. 24, pi. viii. 

Type. Bight mandibular tooth ; British Museum. 

Mandibular tooth robust, the beak being scarcely produced ; oral 
margin with traces of an external thickening layer; symphysial 
facette broad, but occupying only about one quarter of the inner 
aspect ; beak-tritor and the anterior outer tritor laminated ; the 
symphysial extension of the very broad inner tritor also laminated, 
the hinder portion of this and the posterior outer tritor consisting 
of tubules. (?) Palatine tooth with the small posterior inner tritor 
of tubules, the outer and the anterior inner tritors larger and com- 
posed of laminae. 

As remarked by Newton, this imperfectly known species appears 
to be intermediate in its dentition between Ischyodus and Eda- 
phodon. 

Form, fy Log. Albian : Kent. Cenomanian : Cambridgeshire. 

47182. Type specimen ; Gault, Folkestone. Gardner Coll. 

The following specimen indicates an undetermined species of 
Edaphodon : — 

P. 487. Fragment of the anterior portion of a right mandibular 
tooth, described by Agassiz (Poiss. Foss. vol. iii. 1843, 
p. 345, pi. xl. c. figs. 20, 21) as :i maxillaire supe'rieur 

g2 



84 CHIMiKROIDEI. 

droit," and regarded as the type of a Miocene species of 
Ischyodus — Chimcera (Ischyodon) helvetica ; Molasse, 
Olten, Soleure, Switzerland. The specimen is referred to 
Edaphodon by F. J. Pictet, Paleontologie, ed. 2, vol. ii. 
(1854), p. 233. Egerton Coll. 

The following dorsal fin-spines from the English Chalk may also 
be assigned to Edaphodon : — 

39068. Slender spine, somewhat broken, 0*183 in length ; Maid- 
stone. Bowerbank Coll. 

36749. Greater portion of similar spine ; Hailing, Kent. 

Purchased, 1862. 

49731. Similar spine, wanting extremities ; Lewes. Capron Coll. 

P. 1153. fragments of slender spine ; Kent. Egerton Coll. 

46401. Portion of stouter spine; Lower Chalk, Warminster, Wilt- 
shire. Cunnington Coll. 

43390. Portion of large spine ; Burham, Kent. Purchased, 1872. 

P. 6255. Fragments of large spine, provisionally assigned by Agassiz 
to Edaphodon [" Chimosra "] mantelli (Poiss. Foss. vol. iii. 
1843, p. 64, pi. x.6. fig. 17); Lewes. Mantell Coll. 

P. 3097. Basal portion of similar spine ; Lewes. EnnisTcillen Coll. 

49025-6. Portions of two large spines ; locality uncertain. 

Mrs. Smith's Coll. 

A dorsal fin-spine, probably of Edaphodon, has also been described 
from the Cretaceous of Central Eussia by S. Mkitin, Mem. Comite 
Geol. vol. v. no. 2 (1882), p. 42, pi. iv. fig. 16. Another fin-spine, 
possibly of this genus, from the Cretaceous Greensand of New 
Jersey, is named Sphagepoea aciculata, E. D. Cope, Proc. Amer. 
Phil. Soc. vol. xi. (1869), p. 241. 

The species mentioned below have also been determined upon the 
evidence of detached teeth, and, by a misunderstanding of the 
generic characters, the majority of the American forms have hitherto 
been ascribed to Ischyodus. Most of the type specimens of the 
latter are in the collection of Prof. E. D. Cope, Philadelphia, where 
the present writer has had the privilege of examining them ; and 
many of the specific distinctions cited in the diagnoses would be 
regarded as varietal in Britaia. Unless otherwise stated, the type 
specimen is a mandibular toc f h : — 



CHIM^RHLB. 85 

Edaphodon divaricatus : Ischyodus divaricatus, E. D. Cope, Proc. 

Boston Soc. Nat. Hist. 1869, p. 315, and Vert. Cret. Form. 

West (Hep. IT. S. Geol. Surv. Territ. vol. ii. 1875), pp. 285, 

292. — Cretaceous Greensand ; New Jersey. 
Edaphodon eoccenus : Ischyodus eoccenus, E. D. Cope, Vert. Cret. 

Form. West (1875), pp. 285, 288.— Eocene Greensand ; 

Monmouth Co., New Jersey. 
Edaphodon fecundus : Ischyodus fecundus, E. D. Cope, ibid. 

pp. 285, 290. — Cretaceous Greensand ; New Jersey. 
Edaphodon gaskilli : Ischyodus gasJcillii, E. D. Cope, ibid. pp. 285, 

290.— Ibid. 
Edaphodon incrassatus : Ischyodus incrassatus, E. D. Cope, ibid. 

pp. 285, 289.— Ibid. 
Edaphodon Jcelheimensis, J. Riess, Palaeontogr. vol. xxxiv. (1887), 

p. 20, pi. i. fig. 11. — Greensand; Kelheim, Bavaria. 

[Palaeontological Museum, Munich.] 
Edaphodon laterigerus : Ischyodus laterigerus, E. D. Cope, Proc. 

Amer. Phil. Soc. vol. xi. (1871), p. 243, and Vert. Cret. 

Form. West (1875), pp. 284, 288. — Cretaceous Greensand; 

New Jersey. 
Edaphodon longirostris : Ischyodus longirostris, E. D. Cope, Vert. 

Cret. Form. West (1875), pp. 284, 287.— Ibid. 
Edaphodon miersi : Dipristis miersii, 0. C. Marsh, Proc. Amer. 

Assoc. Adv. Sci. 1869, p. 230: Ischyodus miersii, E. D. Cope, 

Vert. Cret. Form. West (1875), pp. 285, 292.— Ibid. 
[Dorsal fin-spine ; Yale College Museum, New Haven.] 
Edaphodon mirificus, J. Leidy, Proc. Acad. Nat. Sci. Philad. 

1856, p. 221, and Ext. Vert. Fauna W. Territ. (Rep. 

U.S. Geol. Surv. Territ. vol. i. 1873), p. 306, pi. xxxvii. 

figs. 6-12 ; E. T. Newton, Chimaeroid Fishes Brit. Cret. 

Rocks (Mem. Geol. Surv. 1878), p. 24 : Ischyodus miri- 
ficus, E. D. Cope, Vert. Cret. Form. West (1875), pp. 285, 

291 . — Ibid. [Mandibular and palatine teeth ; Rutger's 

College, New Brunswick, N.J.] 
Edaphodon monolophus : Ischyodus monolophus, E. D. Cope, Proc. 

Boston Soc. Nat. Hist. 1869, p. 314.— Ibid. 
Edaphodon smocki : Ischyodus smockii, E. D. Cope, ibid. p. 316. 

—Ibid. 
Edaphodon stenobryus : Ischyodus stenobryus, E. D. Cope, Vert. 

Cret. Form. West (1875), pp. 284, 285.— Ibid. 
Edaphodon tripartitus : Ischyodus tripartitus, E. D. Cope, ibid. 

pp. 284, 286 : Ischyodus mirificus, E. D. Cope ('*' errore "), 

Proc. Boston Soc. Nat. Hist. 1869, p. 314.— Ibid. 



St) CII1MJKK0IDEI. 

The right vomerine tooth of a large species of Edaphodon, from 
the Cretaceous of Columbus, Mississippi, now in the Museum of the 
Academy of Natural Sciences, Philadelphia, is described as the 
mandibular tooth of a distinct genus and species, Eumylodus 
laqueatus, J. Leidy, Ext. Vert. Fauna W. Territ. (Rep. U.S. Geol. 
Surv. Territ. vol. i. 1873), p. 309, pi. xix. figs. 21, 22, pi. xxxvii. 
figs. 13, 14. 

The genus Diphrissa, E. D. Cope (Vert. Cret. Form. West, 1875, 
p. 283), is founded upon a mandibular tooth differing only from that 
of the typical Edaphodon in the presence of a single outer tritor — a 
feature noted above in Edaphodon reedi. Two species are recognized 
from the Cretaceous Greensand of New Jersey, the type being 
D. solidula, previously named Ischyodus solidulus (E. D. Cope, Proc. 
Amer. Phil. Soc. vol. xi. 1869, p. 244). The description of the 
second species, D. latidens, Cope, accompanies the generic diagnosis ; 
and both of the type specimens are in the Cope Collection, Phila- 
delphia. 

The following genera and species appear to the present writer to 
be probably founded upon indeterminable fragments of the teeth of 
Edaphodon. They were obtained from the Cretaceous Greensand 
of New Jersey, and are preserved in the Cope Collection : — 

Bryactinus amorphus,~E. D. Cope, Vert. Cret. Form. West (1875), 

p. 282. 
Isotcenia neoccesariensis, E. D. Cope, ibid. p. 293. 

The following genus and species is founded upon a palatine and 
vomerine tooth, of which the former appears to be a broken Edapho- 
dont tooth : — 

Mylognaihus priscus, J. Leidy, Proc. Acad. Nat. Sci. Philad. 
1856, p. 312, and Trans. Amer. Phil. Soc. [2] vol. xi. 
(1859), p. 153, pi. xi. figs. 24-30.— Tertiary Lignite; 
Nebraska. 

The following genus, with three species, is founded upon an 
imperfect mandibular tooth showing only an inner tritor. A palatine 
tooth having long, narrow, outer and inner tritors, is doubtfully 
associated with this : — 

Leptomylus densus, E. D. Cope, Proc. Boston Soc. Nat. Hist, 
vol. xii. (1869), p. 313.—Greensand ; New Jersey. [The 
type species ; E. D. Cope Collection, Philadelphia.] 



CHIM^ERID^:. 87 

Leptomylus coohi, Es D. Cope, Proc. Amer. Phil. Soc. vol. xi. 
(1871), p. 384. — Greensand ; New Jersey. 

Leptomylus forfex, E. D. Cope, Vert. Cret. Form. West (Rep. 
U.S. Geol. Surv. Territ. vol. ii. 1875), p. 281.— Green- 
sand ; New Jersey. 



Genus CALLORHYNCHUS, Gronow. 

[Zoophylacium Gronov. 1763, pt. i. p. 31.] 

Snout with a cartilaginous prominence, terminating in a cutaneous 
flap ; tail heterocercal. Mandibular tooth more or less massive, 
with a well-defined thick band upon the outer aspect immediately 
below the oral margin ; anterior and outer tritors absent or minute ; 
median tritor well developed. Palatine tooth robust, with a well- 
defined thickening upon the outer aspect immediately above the 
oral margin ; a single large tritor, bifurcated anteriorly, occupying 
the greater part of the oral surface. Vomerine teeth more or less 
quadrate in side view. Dorsal fin-spine laterally compressed, 
smooth or longitudinally striated, with a double series of posterior 
denticles. Head-spine of male short, arched, with a terminal 
cluster of denticles. 

Callorhynchus hectori, Newton. 

1876. Callorhynchus hectori, E. T. Newton, Quart. Journ. Geol. Soc. 

vol. xxxii. p. 329, pi. xxi. figs. 6-9. 
1878. Callorhynchus hectori, E. T. Newton, Chimseroid Fishes Brit. 

Cret. Rocks (Mem. Geol. Surv., Monogr. iv.), p. 41, pi. xii. 

figs. 11, 12. 
1888. Callorhynchus hectori, J. W. Davis, Trans. Roy. Dublin Soc. [2] 

vol. iv. p. 41, pi. vii. figs. 14, 15. 

Type. Right palatine tooth : British Museum. 

Palatine tooth slightly differing from that of the recent C. ant- 
arcticus in the more forward production of the two divisions of the 
tritor. 

Form. Sf Loc. " Lower Greensand : " Amuri Bluff, New Zealand. 

P. 2301. Type specimen. By exchange, 1876. 



88 CHIM.EK0IUE1. 

Genus ELASMODECTES, Newton l . 
[Mem. Geol. Survey, Monogr. iv. 1878, p. 43.] 

Mandibular tooth much laterally compressed, with no definite 
thickening upon the outer aspect, and the symphysial facette very 
narrow ; anterior tritor divided into minute points ; median tritor 
absent ; outer tritors represented by marginal series of minute 
points. 

The upper teeth are still unknown. 

Elasmodectes willetti, Newton. 

1878. Elasmognathus icillettii, E. T. Newton, Chimaeroid Fishes Brit. 

Cret. Rocks (Mem. Geol. Surv., Monogr. iv.), p. 43, pi. xii. 

figs. 13-15. 
1888. Elasmodectes tvillettn, A. S. Woodward, Proc. Geol. Assoc. 

vol. x. p. 301. 

Type. Associated right and left mandibular teeth ; Willett Col- 
lection, Brighton Museum. 

The single known species, of small size, the mandibular tooth 
measuring not more than 0*025 in length. 

Form. 6f hoc. Turonian : Sussex and Kent. 

47944. Imperfect right mandibular tooth, inner aspect, noticed by 
Newton, op. cit. p. 44 ; Lower Chalk, Burham, Kent. 

Presented by the Hon. Robert Mar sham, 1877. 

49022, 49024. Left and right mandibular teeth, noticed, ibid. ; 
Burham. Mrs. Smith's Coll. 



Genus ELASMODUS. Egerton. 

[Proc. Geol. Soc. vol. iv. 1843, p. 156.] 

Mandibular tooth much compressed, with no definite thickening 
upon the outer aspect, and the symphysial facette narrow ; one 
large, laminated, anterior tritor present, with one or two minute 
ones below it upon the symphysis ; one large median tritor ; anterior 
outer tritor almost or completely fused with the postero- superior 
angle of the median ; posterior outer tritor laminated and divided 
into several small parts. Palatine tooth very robust, with no well- 
defined thickening upon the outer aspect ; four tritors represented, 

1 This genus was defined by Newton under the preoccupied name of Elasmo- 
gnathus, and the modification here adopted was suggested by the present writer, 
Proc. Geol. Assoc, vol. x. (1888), p. 301. 



CHIM^RTD^. 



89 



the anterior and posterior inner being fused together, the median 
very large and sometimes fused with the posterior inner, and the 
outer tritor much elongated, consisting of laminae. Vomerine tooth 
broad, with several closely-arranged, laminated tritors. 

Elasmodus hunteri, Egerton. 

1840. ' Extinct Chimcera,' R. Owen, Odontography, vol. i. p. 66. 
1843. JElasmodus hunteri, Sir P. Egerton, Proc. Geol. Soc. vol. iv. 

p. 156. 
1847. Elasmodus hunteri, Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. iii. p. 351. 
1850. Elasmodus hunteri, F. Dixon, Foss. Sussex, p. Ill, pi. x. figs. 11, 

12. 
1852. Elasmodus hunteri, Sir P. Egerton, Figs, and Descrips. Brit. 

Organic Remains (Mem. Geol. Surv.), dec. vi. no. 1, pi. i. 
1885. Elasmodus hunteri, F. Noetling, Abh. geol. Specialk. Preussen 

u. Thuring. Staaten, vol. vi. pt. 3, p. 11, pi. i. figs. 2, 3, pi. ii. 

fig. 6. 

Type. Mandibular tooth and theoretically associated vomerine 
tooth ; Royal College of Surgeons. 

The type species. Inner tritor of mandibular tooth at least as 
broad as the space between it and the symphysis, sometimes much 
broader. Median and outer tritors of the palatine tooth extremely 
elongated antero-posteriorly. 

Form. Sf Loc. Lower Eocene (London Clay) : Isle of Sheppey. 
Middle Eocene (Bracklesham Beds): Sussex. Eocene (Zone A,) : 
Samland, Prussia. 

(i.) London Clay ; Isle of Sheppey. 
40203. Left mandibular tooth. Purchased, 1867. 

43110. Similar specimen, less abraded. Wetherell Coll. 

44910. Imperfect right mandibular tooth. 

Presented by Sir Richard Owen, K.C.B , 1874. 

P. 161. Small abraded left mandibular tooth. Purchased, 1880. 

P. 6227. Abraded left palatine tooth. History unknown. 

P. 3080 a. Imperfect right palatine tooth. Enniskillen Coll. 

P. 1157 a. Left vomerine tooth. Egerton Coll. 

(ii.) Bracklesham Beds ; Bracklesham Bay, Sussex. 
P. 6228. Small left mandibular tooth, figured by Egerton, op. cit. 
(1852), pi. i. figs. 3, 4. Dixon Coll 



90 CHIMJ3ROIDEI. 

P. 6229. Much abraded fragmentary left mandibular tooth. 

Di.von Coll. 

38869. Left mandibular tooth, figured by Dixon, op. cit. 

Bowerbank Coll. 

P. 6230. Two examples of the right palatine tooth, figured by Eger- 
fcon, op. cit. (1852), pi. i. figs. 5-8. Divon Coll. 



Elasmodus greenoughi, Agassiz. 

1843. Elasmodus greenovi, Sir P. Egerton, Proc. Geol. Soc. vol. iv. 

p. 156 (name only). 
1843. Elasmodus gi-eenoughii, L. Agassiz, Poiss. Foss. vol. iii. p. 350, 

pi. xl. figs. 11-16. 

Type. Imperfect right mandibular tooth ; British Museum. 
Inner tritor of mandibular tooth considerably narrower than the 
space between it and the symphysis. 

Form. § Loc. Upper Senonian : Belgium. 

P. 483. Type specimen figured by Agassiz, torn. cit. pi. xl. figs. 11, 
12 ; locality unknown, but probably from the Poudingue 
de Malogne, Ciply, near Mons, Belgium. Egerton Coll. 

P. 3079. Two fragments of right mandibular teeth, in similar con- 
dition, one figured by Agassiz, op. cit. pi. xl. figs. 15, 16. 

Enniskillen Coll. 

P. 5837. Imperfect left mandibular tooth, wanting sj-mphysis ; 
Ciply. Presented by Mons. A. Houzeau de Lehaie, 1888. 

P. 483 a. Fragment of tooth, in similar condition to the type speci- 
men, determined to be vomerine by Agassiz, torn. cit. p. 350, 
pi. xl. figs. 13, 14, but probably the symphysial region of 
the mandibular tooth. Egerton Coll. 

Closely related to Elasmodus is the fragmentary tooth named 
thus :— 

Psaliodus compressus, Sir P. Egerton, Proc. Geol. Soc. vol. iv. 
(1843), p. 157.— (?) London Clay: Sheppey. [Mandib. 
tooth ; Royal College of Surgeons, London.] 



CHIM^RID.^. 



91 



Genus CHIMiERA, Linna3us. 
[Syst. Nat. ed. 12, vol. i. 1766, p. 401.] 

Syn. (?) Dipristis, P. Gervais, Zool. et Pal. Gen. 1869, p. 240. 

Snout soft, prominent, without appendage ; tail diphy cereal. 
Mandibular tooth laterally compressed, with no well-defined thick- 
ening upon the outer aspect immediately below the oral margin, and 
the symphysis narrow ; anterior tritor minute, anterior outer tritor 
subdivided into two or three small portions, posterior outer tritor 
similar; median tritor large. Palatine tooth moderately robust, 
with a slightly defined thickening upon the outer aspect ; anterior 
and posterior inner tritors small ; median tritor small ; outer tritor 
extending throughout the oral margin, subdivided into a series of 
small points. Yomerine tooth quadrate in side view. Dorsal fin- 
spine laterally compressed, smooth or longitudinally striated, with a 
double series of posterior denticles. Head-spine of male short, 
arched, with a terminal cluster of denticles. 



Chimsera pliocenica, sp. nov. 
[Plate I. fig. 15.] 

Type. Right palatine tooth ; British Museum. 

A very large species, the antero-posterior measurement of the 
palatine tooth being not less than 0-025. Palatine tooth compara- 
tively robust ; posterior inner and median tritors of about equal 
size ; anterior inner tritor small and narrow, fixed upon the down- 
wardly-curved anterior extremity of the tooth. 

Teeth probably for the most part referable to this species have 
been determined as Ischyodus egertoni, Edaphodon mantelU, E. bucJc- 
landi, and E. leptognatlius (R. Lawley, Nuovi Studi Pesci, etc. 
Colline Toscane, 1876, p. 51). 

Form. Sf Log. Pliocene : Tuscany. 

47032. Type specimen, shown of the natural size, from three aspects, 
in PI. I. fig. 15, a-c ; Orciano, Tuscany. 

Purchased, 1875. 

A small species has also been described as follows : — 

Chimcera javana, K. Martin, Samml. geol. Reichs-Museum Leiden 
[1] vol. iii. (1883), p. 30, pi. ii. figs. 25, 26.— Tertiary ; 
jSTgembak, Java. [Upper teeth; Leyden Museum.] 



92 lOnTHYODORULITES. 

The original of the following specimen is also referable to a large 
extinct Bpecies either of Chimcera or Edaphodon : — 

P. 1160. Plaster cast of imperfect dorsal fin-spine, described and 
figured under the name of Dipristis chimceroides, P. Ger- 
vais, Zool. et Pal. Generates (1867-69), p. 241, pi. xlvi. 
fig. 5 ; Miocene, Leognan, Gironde. Egerton Coll. 

Either to Chimcera or Edaphodon may be assigned the fragments 
of teeth from the Molasse of Baltringen, Wiirtemberg, named 
Chimcera deleta, J. Probst, Wiirtt. Jahresh. vol. xxxviii. (1882) 
p. 131, pi. ii. fig. 17. 

The so-called Chimcera furcata, A. Fritsch (Kept, u. Fische bbhm. 
Kreideform. 1878, p. 16, woodc), from the Cretaceous of Bohemia, 
is founded upon one of the problematical teeth named Plethodus by 
Dixon (Foss. Sussex, 1850, p. 366). The type specimen is preserved 
in the Koyal Bohemian Museum, Prague, and has been examined 
by the present writer. 

It is interesting to add that a small Chimseroid fish, exhibiting the 
typical dentition of the Chimseridae, but destitute of a rostral spine 
both in the male and female, has lately been discovered in the deep 
sea off the Atlantic coast of North America. The genus is named 
Harriotta by Goode and Bean (Proc. Biol. Soe. Washington, vol. iii. 
1886, p. 104, footnote), and the type specimens are preserved in the 
Smithsonian Institution. 



ICHTHYODORULITES. 

The characters of the dermal spines and tubercles of cartilaginous 
fishes vary so much in the different genera, and are sometimes so 
completely identical when other parts are quite distinct, that all 
fossils of this nature hitherto only discovered in an isolated condition 
may be conveniently grouped together under the denomination of 
Ichthyodoeulites. The term was first employed by Buckland and 
De la Beche, who were the earliest to discover the true nature of 
these fossils ; it was subsequently applied by Agassiz (op. cit.) to all 
fossil spines of Elasmobranch and Chimaeroid fishes, whether corre- 
lated with the teeth or not ; and we now propose to restrict the 
name to those detached dermal spines, tubercles, and plates which 
exhibit the microscopical structure of vascular dentine, and are thus 



ICHTHTODOHULITES. 93 

probably referable, for the most part, to one or the other of the sub- 
classes just mentioned, but cannot yet be precisely determined. 

The various " genera " already recognized may be briefly defined 
and discussed ; but, although it is convenient to adopt provisional 
specific names for such fossils, future discoveries may soon lead to a 
more precise systematic allocation of most of the forms, and it will 
thus suffice merely to refer to the published diagnoses, without 
repeating them. 

For convenience of reference, it is proposed to arrange the Ich- 
thyodorulites in five groups, as follows : — 

I. Slender elongated spines, bilaterally symmetrical, the inserted 

portion smooth and usually sharply separated from the 
ornamented exserted portion ; internal cavity open poste- 
riorly towards the base. Resembling the dorsal fin-spines 
of the Cestraciontidae, and probably for the most part 
referable to that family and to the Cochliodontidse. 

Onchus, Ctenacanthus, Anaclitacanthus, Eunemacanthus, 
Homacanthus, Hoplonchus, Acondylacanihus, Asteropty- 
chius, Cosmacanthus, Bythiacanthus, Glymmatacanthus, 
Thaumatacanthus, Chalazacanthus, Lispacanthus, Lepra- 
canthus, Nemacanihus, (?) Psilacanihus. 

II. Slender elongated spines, bilaterally symmetrical, with the 

internal cavity only open at the base, and little or no 
smooth inserted portion. 

Gnathacanthus, Apateacanthus, Pristacanthus, Codorhyn- 
chus. 

III. Paired spines, of which some may have been placed in front 

of fins, but of which many are broad, with insignificant 
base of insertion, and must have been arranged as inde- 
pendent dermal armour. 

Machceracanthus, Haplacanthus, Heter acanthus, Psam- 
mosteus, Stethacanthus, Physonemus, (?) Batacanthus. Sti- 
chacanthus, Oracanthus, Antacanthus, Gyracanthus, Agana- 
canihus. 

IV. Spines probably not placed in advance of fins, but most 

nearly resembling the head-spines of the male Chimaeroids 
and some Mesozoic Cestraciont Sharks (e. g. Hybodus). 

Erismacanihus, Gampsaeanthus, Leer acanthus, Dipria- 
canthus, Listr acanthus, Byssacanthus, Cyrtacanthus, Eua- 
canihus, Harpacanthus, Ostracacanthus. 
Y. Dermal defences of doubtful position. 

Edestus, Cynopodius, Euctenius. 



94 [CHTHTODORXrUTEB. 

I, Slender elongated spines, bilaterally symmetrical; the inserted 
portion smooth and usually sharply separated from the orna- 
mented exserted portion ; internal cavity open posteriorly 
towards the base. Resembling the dorsal fin-spines of the 
(Vstraciontidae, and probably for the most part referable to 
that family and to the Cochliodontidas. 



Genus ONCHUS, Agassiz. 
[Poiss. Foss. vol. iii. 1837, p. 6. J 

Syn. Archceacanthus, G. Kade, Programm. k. Realschule zu Meseritz, 
1858, p. 19. 

Spines of small size, laterally compressed ; sides of exserted por- 
tion ornamented with smooth or faintly crenulated longitudinal 
ridges ; no posterior denticles. 

Onchus murchisoni, Agassiz. 

1837. Onchus murchisoni, L. Agassiz, Poiss. Foss. vol. iii. p. 6, pi. i. 

fig. 1 (? non fig. 2). 
]839. Onchus murchisoni, L. Agassiz, in Murchison's Silur. Syst. p. 607, 

pi. iv. figs. 9, 11 (? non fig. 10). 
y 1853. Leptocheles murchisoni, F. M'Coy, Quart. Journ. Geol. Soc, 

vol. ix. p. 14. 
1853. Onchus murchisoni, J. W. Salter, in Murchison, Quart. Journ. 

Geol. Soc. vol. ix. p. 16. 

Type. Olim Murchison Collection. 

The type species, regarded by M'Coy as founded upon fragments 
of Crustacean appendages, but stated by Salter to be undoubtedly 
based in part upon fish-spines. The type specimens are unfortu- 
nately lost \ but the spines enumerated below exhibit the characters 
described by Agassiz. 

Form. Sf Loc. Upper Ludlow : Herefordshire, Shropshire, and 
Radnorshire. Lower Old Red Sandstone : Herefordshire 2 . 

42250-1. Two fragments : Upper Ludlow, Linley Brook. 

Baugh Coll. 

1 Murchison, Quart. Journ. Geol. Soc. vol. ix. 1853, p. 16. 

2 Doubtful specimens from the Upper Silurian of the Isle of Oesel, and the 
Devonian of N.W. Russia, are also assigned to this species by C. H. Pander, 
Foss. Fische Silui. Syst. (1856) p. 70, pi. iv. fig. 20, pi. vi. figs. 26, 27, and E. 
Ton Eichwald, Leth. Rossica, vol. i. (1860^, p. 1594. A fragmentary spine 
much resembling this species, from Ofvedskloster, Scania, is also preserved 
in the State Museum, Stockholm. 



ICHTHYOuORULIXES. 95 

42257. Fragment in bone-bed ; Ludlow. Baugh Coll. 

P. 5085. Portion of Ludlow bone-bed, with several fragments of 
spines ; Norton, near Craven Arms. 

Presented by J. E. Lee, Esq., 1885. 

45978. Imperfect spine ; L. Old Red Sandstone, Bush Pitch, Led- 
bury, Herefordshire. Lightbody Bequest. 

P. 2249. Imperfect spine and fragment ; L. Old Red Sandstone, 
Ledbury. Egerton Coll. 

P. 2868, P. 3124. Fragment, and block of sandstone with numerous 
fragments; L. Old Red Sandstone, Ledbury. 

EnnisJcillen Coll. 



Onchus tenuistriatus, 

1837. Onchus tenuistriatus, L. Agassiz, Poiss. Foss. vol. iii. p. 7, pi. i. 

fig. 10. 
1837. Onchus semistriatus, L. Agassiz, ibid. p. 8, pi. i. fig. 9. 
1839. Onchus tenuistriatus, L. Agassiz, in Murchison's Silur. Syst. 

p. 607, pi. iv. figs. 12, 13, 57-59. 
1839. Onchus semistriattis, L. Agassiz, ibid. p. 596, pi. ii. figs. 12, 13. 
1845. Onchus semistriatus, L. Agassiz, Poiss. Foss. V. G. R. p. 118, 

pi. xxxiii. fig. 37. 
(?) 1885. Onchus tenuistriatus, F. Roemer, Palaeont. Abhandl. vol. ii. 

p. 358, pi. xxxi. fig. 19. 

Type. Olim Murchison Collection. 

The examples of this species recorded below indicate that the 
fragment named 0. semistriatus is a portion of the distal half of the 
spine, in which the smooth posterior area becomes relatively very 
large. 

Form. Sf Loc. Upper Ludlow and Downton Sandstone : Hereford- 
shire. Lower Old Red Sandstone : Herefordshire l . 

P. 5090. Imperfect spine ; Downton Sandstone, Kington. 

Presented by J. E. Lee, Esq., 1885. 

45975-76. Basal half of spine, and imperfect impression of another; 
L. Old Red Sandstone, Bush Pitch, Ledbury, Hereford- 
shire. Lightbody Bequest. 

P. 2249 a. Imperfect spine ; Ledbury. Egerton Coll. 

P. 2865-66. Five spines, one associated with a fragment of a similar 
spine; Ledbury. EnnisJcillen Coll. 

1 Doubtful specimens from the Devonian of Slawjanta, near Pawlowsk, 
St. Petersburg, are also described by E. von Eichwald, Leth. Kossica, vol i. 
(1860), p. 1595, pi. lr. fig. 7. 



96 1CHTHYODORULITES. 

P. 6027. Gutta-percha cast of specimen assigned to this species by 
Roemer, loc. cit., differing only from the typical spines in 
the apparent absence of the smooth posterior area distally ; 
original in the Museum of the University of Breslau, and 
obtained from a boulder, Lyck, East Prussia. 

Presented by Prof. Ferdinand Roemer, 1889. 

Onchus quadrisulcatus (Kade). 

1858. Archceacanthns quadrisulcatus, G. Kade, Programm. k. Real- 

schule zu Meseritz, p. 19, figs. 11, 12. 
1885. Archceacanthus quadrisulcatus, F. Roemer, Palaeont. Abhandl. 

vol. ii. p. 386, pi. xxxiv. fig. 22. 

Type species of Archceacanthus. 

Form. Sf Loc. Devonian Boulders : Prussia and Silesia. 

P. 6028. Gutta-percha cast of specimen figured by Roemer ; original 
from Lyck, E. Prussia, preserved in the Breslau University 
Museum. Presented by Prof. Ferdinand Roemer, 1889. 

Onchus (?) granulatus, Roemer. 

1885. Onchus granulatus, F. Roemer, Palaeont. Abhandl. vol. ii. p. 358, 
pi. xxxi. fig. 18. 

Type. University of Breslau. 

Form. Sf Loc. Upper Silurian (Beyrichien-Kalk) ; unknown. 

P. 6026. Gutta-percha cast of type specimen ; original from boulder 
near Nieder-Kunzendorf, near Freiburg, Silesia. 

Presented by Prof. Ferdinand Roemer, 1889. 

The following spine has been assigned to Onchus, but is not suffi- 
ciently well preserved for satisfactory determination. In many 
respects the specimen is suggestive of Machcer acanthus. 

P. 2864. Type specimen of Onchus major, Etheridge, described in 
Rep. Brit. Assoc. 1871, Trans. Sect. p. 110 ; Lower Old 
Red Sandstone, Llidiart-y-Warn Quarry, near Hay, 
Brecon. Enniskillen Coll. 

The following species have also been described, but there are no 
examples in the Collection, and some may be mere fragments of 
Crustacea : — 

Onchus clintoni, E. W. Claypole,*Quart. Journ. Geol. Soc. vol. xli. 
(1885), p. 61, woodc. fig. 6.— Clinton Group ; Perry Co., 
Pennsylvania. 



TCHTHYODOKULITES. 97 

Onchus cwvatus, C. H. Pander, Foss. Fische Siiur. Syst. (1856), 
p. 70, pi. vi. fig. 29. — Upper Silurian ; Baltic Provinces. 

Onchus dubius, C. H. Pander, ibid. p. 71, pi. vi. fig. 28. — Ibid. 

Onchus jpennsylvanicus, E. W. Claypole, torn. cit. (1885), p. 61, 
woodc. fig. 5. — Bloomfield Sandstone ; Perry Co., Penn- 
sylvania. 

Onchus sublcevis, L. Agassiz, Poiss. Foss. V. G. R. (1845), p. 118, 
pi. xxxiii. figs. 19-21. [Doubtfully assigned to 0. mur- 
chisoni by E. von Eichwald, Leth. Rossica, vol. i. (1860), 
p. 1595.] — Devonian ; St. Petersburg. 

Two doubtful Onchus-shsupedi fossils from tbe Lower Old Red 
Sandstone of Abergavenny, Monmouthshire, are named Ptychacanthus 
dubius, L. Agassiz, Poiss. Foss. vol. iii. (1843), p. 176, and Poiss. 
Foss. V. G. R. (1845), p. 118, pi. xxxiii. figs. 22, 23. 

Very doubtful are Onchus compressus, E. von Eichwald (Leth. 
Rossica, vol. i. 1860, p. 1595), previously figured without specific 
name in Keyserling, Reise in das Petschoraland (1846), p. 291, 
pi. xxi. fig. a, from so-called Permian, Kischerma, Petchora-Land : 
and 0. tricarinatus, C. H. Pander (op. cit. p. 71, pi. vi. fig. 30), 
from the Silurian of the Baltic Provinces. 

The so-called 0. deiveyi, J. Hall (Paleeont. New York, vol. ii. 1852, 
p. 320, pi. lxxi. fig. 1), is a fragment of the Crustacean Ceratiocaris ; 
it was obtained from the Niagara Group of Lockport and Rochester, 
New York State. 

Another Devonian Ichthyodorulite, apparently related to Onchus, 
has also been named as follows : — 

Naidas, L. Agassiz (Poiss. Foss. V. G. R. 1845, p. 116), with one 
species, N. sidcatus, Agassiz (ibid. p. 116, pi. xxxiii. fig. 10), from St. 
Petersburg. 

A very doubtful Devonian Ichthyodorulite from Petchora-Land 
is also named Dimeracanthus concentricus, A. von Keyserling, Reise 
in das Petschoraland (1846), p. 292 b ; and another from the Go- 
vernment of Orel is termed Pycnacanthus, G. Fischer de Waldheim, 
Bull. Soc. Imp. Nat. Moscou, vol. xxv. (1852), pt. i. p. 174, pi. ii. 
fig. 10. 



Genus CTENACANTHUS, Agassiz. 

[Poiss. Foss. vol. iii. 1837, p. 10.] 

Dorsal fin-spines robust, often attaining to a large size, laterally 
compressed ; sides of exserted portion ornamented with longitudinal 
ridges, usually crenulated or denticulated, rarely smooth ; posterior 

PART II. H 



98 1CRTHY0D0RT7L1TES. 

face flat or concave, with a series of small denticles upon each 
margin. 

Spines of this character doubtless characterize more than one 
genus. They have already been discovered in association with 
hybodont teeth, indicating a shark with two armed dorsal fins ! ; 
but they are also abundantly met with in beds where no such teeth 
occur. Agassiz ~ supposed that they were the spines of Psammodus ; 
some palaeontologists have suggested 3 that they may be correlated 
with the teeth named Cladodus, though at the same time erroneously 
identifying certain Coal-Measure fossils with these : and Dr. J. S. 
Newberry suspects \ from a discovery in the Waverly Shales of Ohio, 
that Ctenacanthus and Orodus may be synonymous. It is certainly 
noteworthy that in Britain the largest spines of this type occur in 
the Bristol Carboniferous Limestone, where also are discovered the 
largest teeth of Orodus ; and the " species " are most numerous at 
Armagh, where Orodus exhibits the greatest variety. 

Ctenacanthus major, Agassiz. 

1837. Ctenacanthus major, L. Agassiz, Poiss. Foss. vol. iii. p. 10, pi. iv. 
1837. Ctenacanthus tenuistriatus, L. Agassiz, ibid. p. 11, pi. iii. figs. 

7-11. [Bristol Museum and British Museum.] 
1850. Ctenacanthus tenuirostris, F. A. Roerner, Paheontogr. vol. iii. 

p. 53, pi. viii. fig. 18 (misprint). 
1878. Ctenacanthus tenuistriatus, L. G. de Koninck, Faune Calc. Carb. 

Belg. pt. i. p. 67, pi. vii. fig. 2. 
(?) 1878. Ctenacanthus maximus, L. G. de Koninck, ibid. p. 68, pi. vii. 

fig. 1. [Brussels Museum.] 
1883. Ctenacanthus major, J. W. Davis, Trans. Roy. Dublin Soc. [2] 

vol. i. p. 334, pi. xlii. figs. 1, 2. 
1883. Ctenacanthus tenuistriatus, J. W. Davis, ibid. p. 335, pi. xliii. 

figs. 1, 2. 
1883. Ctenacanthus salopiensis, J. W. Davis, ibid. p. 339, pi. xliv. fig. 6. 

[British Museum.] 

Type. Bristol Museum. 

The type species, attaining a very large size. 

Form. Sf Log. Lower Carboniferous Limestone : Gloucestershire 
and Belgium. Carboniferous Limestone : Shropshire. Lower Car- 
boniferous (Posidonomyen-Schiefer) : Upper Harz 5 . 

1 See Sjphenacanthits, Pt. I. p. 241. - Poiss. Foss. vol. iii. p. 171. 

3 Hancock & Atthey, Ann. Mag. Mat. Hist. [4] vol. ix. (1872), p. 260 ; 
J. Thomson, Trans, Glasgow Geol. Soc. -vol. iv. (1871), p. 59. 

* Eep. Geol. Survey Ohio, vol. ii. pt. ii. (1875), p. 54. 

5 A fragmentary spine, of doubtful species, from the Lower Carboniferous 
Limestone of the Govt, of Toula, is also named Ctenacanthus 'major, H. Traut- 
schold, Nouv. Mem. Soc. Imp. Nat. Moscou, vol. xiii. p. 273, pi. xxvii. fig. 18. 



1CHTIIY0D0RTTLTTES. 99 

P. 2534. Spine figured by J. W. Davis, loc. cit. pi. xlii. fig. 1: Bristol. 

Ennislcillen Coll. 

P. 3113-16. Three imperfect spines, and a fragment of the base of 
another bearing Agassiz's MS. label : Bristol. 

Ennislcillen Coll. 

P. 4201. Polished fragment ; Bristol. Enniskillen Coll. 

P. 2224. Three imperfect spines ; Bristol. Egerton Coll. 

41082. Polished fragment : Bristol. 

Presented by J. J. Bennett, Esq., 1868. 

The following specimens appear to differ from the foregoing only 
in their smaller size : — 

P. 495, P. 2225. Imperfect terminal half of exserted portion of 
spine, being one of the type specimens of C. tenuistriatus 
figured by Agassiz, torn. cit. pL iii. fig. 7 ; Bristol. The 
other portion of this fossil is in the Bristol Museum. 

Egerton Coll. 

P. 3109. Spine assigned to C. tenuistriatus by J. W. Davis, loc. cit. 
pi. xliii. fig. 1 ; Bristol. Ennislcillen Coll. 

P. 3110. Half of spine in lougitudinal section, polished, and labelled 
in Agassiz's handwriting thus : — " Probablement le rayon 
des dents nominees Psammodus porosus, decrit sous le 
nom de Ctenacanthus tenuistriatus, Ag." ; Bristol. 

Ennislcillen Coll. 

P. 2522. Fragment ; Bristol. Ennislcillen Coll. 

22665. Basal half of spine ; Bristol. Purchased. 

P. 2523. Type specimen of Ctenacanthus salopiensis, J. W. Davis ; 
Oreton, Shropshire. Enniskillen Coll. 

42238. Short stout spine ; Oreton. Baugh Coll. 
P. 213. Spine, imperfect distally ; Oreton. Weave?'- Jones Coll. 
42233. Several fragments ; Oreton. Baugh Coll. 
36466. Fragment ; Oreton. Presented by G. E. Roberts, Esq., 1862. 

42239. Fragment, with very large anterior longitudinal ridges, 

probably assignable to C. major ; Oreton. Baugh Coll. 

n2 



100 ICHTHYODORUL1TRS. 

Ctenacanthus denticulatus, M'Coy. 
L848. Ltenacanthus denticulatus, F. M'Coy, Ann. Mag. Nat. Hist. [2] 

vol. ii. p. 116. 
1855. Ctenacanthus denticulatus, F. M'Coy, Brit. Paheoz. Foss. p. 625 

pi. iii. k. fig-. 16. 
1883. Ctenacanthus denticulatus, J. W. Davis, Trans. Roy. Dublin Soc. 

[2] vol. i. p. 338, pi. xliv. fig. 4. 

Type. Woodwardian Museum, Cambridge. 

Form. § Loc. Lower Carboniferous Limestone : Armagh and 
Shropshire. Lower Carboniferous : Monaduff, Drumlish, N. Ireland. 

41193-94. Two imperfect small spines ; Oreton, Shropshire. 

Purchased, 1868. 

42237. Fragment ; Oreton. Baugh Coll. 

Ctenacanthus brevis, Agassiz. 

1837. Ctenacanthus brevis, L. Agassiz, Poiss. Foss. vol. iii. p. 11, pi. ii. 

fig. a. 

1883. Ctenacanthus brevis, J. W. Davis, Trans. Roy. Dublin Soc. [2] 

vol. i. p. 337, pi. xliii. fig. 3. 
1883. Ctenacanthus limaformis, J. W. Davis, ibid. p. 339, pi. xliv. fig. 5. 

[British Museum.] 

Type. Bristol Museum. 

Form. Sf Log. Lower Carboniferous Limestone : Bristol. 

22665. Two partially broken spines, naturally associated, the hinder 
being smaller and narrower than the foremost. 

Purchased, 1848. 

34982. Imperfect example. Purchased, 1860. 

P. 2226. Spine, and fragment labelled by Agassiz. Egerton Coll. 

P. 3111-2. Spine figured and described by J. W. Davis, torn. cit. 
p. 337, pi. xliii. fig. 3 ; also a fragment labelled by 
Agassiz. Enniskillen Coll. 

P. 6231. Fragmentary specimen. Purchased. 

P. 2535. Type specimen of C. limaformis, J. W. Davis, loc. cit. 
p. 339, pi. xliv. fig. 5. This is a much brokeu spine, and 
so far as its characters*are distinguishable cannot be sepa- 
rated from C. brevis; the published figure is misleading. 

Enniskillen Coll. 






ICHXHYODORTTLITES. 101 

Ctenacanthus heterogyrus, M'Coy. 

1843. Ctenacanthus heterogyrus, L. Agassiz, Poiss. Foss. vol. iii. p. 177 

(name only). 
1855. Ctenacanthus heterogyrus, F. M'Coy, Brit. Palaeoz. Foss. p. 625, 

pi. iii. i. fig. 32. 
(?) 1878. Ctenacanthus heterogyrus, L. G. de Koninck, Fanne Calc. 

Carb. Belg. pt. i. p. G6, pi. vii. fig. 3. 
1883. Ctenacanthus heterogyrus, J. W. Davis, Trans. Roy. Dublin Soc. 

[2] vol. i. p. 336, pi. xliv. figs. 1-3. 

Type. Woodwardian Museum, Cambridge. 

Form, fy Log. Lower Carboniferous Limestone : Armagh, and 
(?) Tournai, Belgium. 

P. 2526-7. Two specimens, much worn at the distal extremity, 
figured by J. W. Davi3, Joe. cit. Enniskillen Coll. 

P. 2528, P. 2671. Seven imperfect specimens, similarly worn dis- 
tally ; also a much abraded spine, probably of the same 
species. Enniskillen Coll. 

P. 2228. Spine extremely worn distally. Egerton Coll. 

28928-29. Two fragmentary spines. Purchased, 1854. 

The following is an indeterminable crushed and broken spine 
slightly smaller than most examples of C. heterogyrus : — 

P. 2530. Type specimen of Ctenacanthus chibius, J. W. Davis, loc. cit. 
p. 340, pi. xliv. fig. 7 ; Lower Carboniferous Limestone, 
Armagh. Enniskillen Coll. 

Ctenacanthus sulcatus (Agassiz). 

1837. Onchus sulcatus, L. Agassiz, Poiss, Foss. vol. iii. p. 8, pi. i. fig. 6. 
1883. Ctenacanthus sulcatus, J. W. Davis, Trans. Roy. Dublin Soc. [2] 
vol. i. p. 343, pi. xlv. fig. 3. 

Type. Bristol Museum. 

Form. <$f Loc. Lower Carboniferous Limestone : Gloucestershire, 
Shropshire, and (?) Armagh, Ireland. 

P. 228. Imperfect exserted portion of spine ; Oreton, Shropshire. 

Weaver-Jones Coll. 

P. 2670. Smaller, more slender spine, similarly marked; Armagh. 

Enniskillen Coll. 

P. 2871. Very small spine, similarly marked and distally worn; 
Armagh. Enniskillen Coll. 



102 u'-irrnYonoRULiTES. 

Ctenacanthus (?) laevis, Davis. 
L883. Ctenacanthus tevis, J. W. Davis, Trans. Roy. Dublin Soc. [2] 
vol. i. p. 341, pi. xlv. fig. 1. 

Type. Bristol Museum. 

This species may pertain to Acondylacanthus. 

Form. 4' Loc. Lower Carboniferous Limestone : Armagh. 

P. 2531. Type specimen. Ennishillen Coll. 

P. 2532-3, P. 2873. Three imperfect spines. Enniskillen Coll. 

39166. Much crushed imperfect spine. Bowerhank Coll. 

Ctenacanthus (?) pustulatus, Davis. 
1883. Ctenacanthus pustulatus, J. W. Davis, Trans. Roy. Dublin Soc. 
[2] vol. i. p. 344, pi. xlv. fig. 2. 

Type. British Museum. 

This species may pertain to Aster optychius. 

Form. Sf Log. Lower Carboniferous Limestone : Armagh. 

P. 2529. Type specimen. EnnisTcillen Coll. 

The following species have also been described, but there are no 
examples in the Collection : — 

Ctenacanthus angulatus, Newberry & Worthen, Pal. Illinois, 

vol. ii. (1866), p. 118, pi. xii. fig. 4. — Chester Limestone ; 

Illinois. 
Ctenacanthus angustus, J. S. Newberry, Palaeoz. Fishes N. America 

(Mon.U.S. Geol. Surv. no. xvi. 1889), p. 181.— Berea Grit 

(Lower Carboniferous) ; Berea, Ohio. 
Ctenacanthus burlingtonensis, St. John & Worthen, Pal. Illinois, 

vol. vi. (1875), p. 426, pi. xv. figs. 6, 7. — Upper Burlington 

Limestone ; Illinois and Iowa. [? Acondylacanthus.] 
Ctenacanthus buttersi, St. John & "Worthen, op. cit. vol. vii. (1883), 

p. 240, pi. xxii. fig. 2. — Lower Coal-Measures ; Illinois. 
Ctenacanthus cannaliratus, St. John & Worthen, op. cit. vol. vii. 

p. 239, pi. xxi. fig. 3. — Chester Limestone ; Illinois. 
Ctenacanthus clarhi, J. S. NewBerry, Palseoz. Fishes N. America 

(Mon. U.S. Geol. Surv. no. xvi. 1889), p. 168, pi. xxvi. 

figs. 2, 3. — Cleveland Shale (Lower Carboniferous ) ; Berea, 

Ohio. [Columbia College, New York.] 



ICHTHYODORULITES. 103 

Ctenacanthus compressus, J. S. Newberry, Ann. New York Acad. 

Sci. vol. i. (1878), p. 191, and Palseoz. Fishes N. America 

(Mon. U.S. Geol. Surv. no. xvi, 1889), p. 168, pi. xxiii. 

fig. 4. — Cleveland Shale (Lower Carboniferous); Lorain Co., 

Ohio. [Columbia College, New York.] 
Ctenacanihus coccianus, St. John & Worthen, op. cit. vol. vii. 

p. 233, pi. xxi. fig. 1. — Keokuk Limestone ; Iowa. 
Ctenacanihus crenatus. F. M'Coy, Brit. Palseoz. Foss. 1855, p. 624, 

pi. iii. i. fig. 31 : Ctenacanthns crenidatus, L. Agassiz, Poiss. 

Foss. vol. iii. (1843), p. 177 (name only) ; J. W. Davis, 

Trans. Eoy. Dublin Soc. [2] vol. i. (1883), p. 345, pi. xlv. 

fig. 6. — Lower Carboniferous Limestone ; Armagh, Ireland. 

[Woodwardian Museum, Cambridge.] 
Ctenacanihus cylindricus, J. S. Newberry, Palaeoz. Fishes N. 

America (Mon. U.S. Geol. Surv. no. xvi. 1889), p. 202, 

pi. xxvi. fig. 1. — Keokuk Limestone Shale ; Casey Co., 

Kentucky. 
Ctenacanthus deflexus, St. John & "Worthen, op. cit. vol. vii. 

p. 234, pi. xxii. fig. 1. — St. Louis Limestone; Illinois. 
Ctenacanthus elegans, M. Tuomey, Geol. Alabama (1858), p. 38, 

woodcut fig. A. — Lower Carboniferous : North Alabama. 
Ctenacanthus eoccavatus, St. John & Worthen, op. cit. vol. vi. 

p. 428, pi. xv. figs. 4, 5. — Keokuk Limestone ; Iowa and 

Missouri. 
Ctenacanthus formosus, J. S. Newberry, Rep. Geol. Surv. Ohio, 

vol. i. pt. ii. (1873), p. 328, pi. xxxvi. fig. 2, and ibid. 

vol. ii. pt. ii. (1875), p. 53, pi. lix. fig. 1. — Waverly Group ; 

Ohio and Kentucky. [Columbia College, New York.] 
Ctenacanthus fur cicarinatus, J. S. Newberry, op. cit. vol. ii.pt. ii. 

p. 54, pi. lix. fig. 2. — Waverly Group ; Kentucky. 

[Associated with teeth of Orodus variabilis.'] 
Ctenacanthus gemmatus, St. John & Worthen, op. cit. vol. vi. 

p. 429, pi. xv. figs. 9, 10. — St. Louis Limestone ; Illinois. 
Ctenacanthus gradocostus, St. John & Worthen, op. cit: vol. vi. 

p. 425, pi. xv. figs. 2, 3. — Upper Burlington Limestone ; 

Iowa and Illinois. 
Ctenacanthus harrisoni, St. John & Worthen, op. cit. vol. vii. 

p. 236, pi. xxiii. fig. 1. — St. Louis Limestone; Illinois. 
Ctenacanthus TceoJcuJc. St. John & Worthen, op. cit. vol. vi. p. 427, 

pi. xv. fig. 8. — Keokuk Limestone ; Illinois, Iowa, and 

Missouri. 
Ctenacanthus littoni, J. S. Newberry, Palseoz. Fishes N. America 

(Mon. U.S. Geol. Surv. no. xvi. 1889), p. 201, pi. xxv. 

fig. 3. — St. Louis Limestone ; St. Louis, Missouri. 



104 lrUTHYODORTJLITES. 

Ctaiacantlw.s marslii, J. S. Newberry, Eep. Geol. Surv. Ohio, 
vol. i. pt. ii. p. 326, pi. xxxvi. fig. 3. — Coal-Measures; Ohio. 
Ctenacanthus maiji, Newberry & Worthen, Pal. Illinois, vol. iv. 
(1870), p. 372, pi. ii. fig. 2. — Lower Carboniferous Lime- 
stone ; Iowa. 

Ctenacanthus pellensis, St. John & Worthen, Pal. Illinois, vol. vii. 
p. 237, pi. xxi. fig. 2. — St. Louis Limestone ; Iowa. 

Ctenacanthus plicatus, J. W. Davis, Trans. Roy. Dublin Soc. [2] 
vol. i. (1883), p. 342, pi. xlv. fig. 4 : Onchus plicatus, 
L. Agassiz, Poiss. Foss. vol. iii. (1843), p. 177 (name 
only). — Lower Carboniferous Limestone ; Armagh. [Mus. 
Geol. Soc., London.] 

Ctenacanihus pugiunculus, St. John & Worthen, op. cit. vol. vi. 
p. 430, pi. xxi. fig. 9. — St. Louis Limestone ; Missouri. 

Ctenacanthus randalli, J. S. Newberry, Palseoz. Fishes N. America 
(Mon. U.S. Geol. Surv. no. xvi. 1889), p. 105.— Chemung 
Group (Olean Conglomerate) ; Warren, Pa. 

Ctenacanthus rectus, J. W. Davis, loc. cit. vol. i. p. 345, pi. xlv. 
fig. 5 : Onchus rectus, L. Agassiz, Poiss. Foss. vol. iii. 
(1843), p. 177 (name only). — Lower Carboniferous Lime- 
stone ; Armagh. [Mus. Geol. Soc. London.] 

Ctenacanthus sculptus, St. John & Worthen, op. cit. vol. vi. p. 421, 
pi. xiv. fig. 1. — Kinderhook Limestone ; Iowa. 

Ctenacanthus similis, St. John & Worthen, op. cit. vol. vi. p. 431, 
pi. xv. fig. 11. — Chester Limestone; Illinois. 

Ctenacanthus speciosus, St. John & Worthen, op. cit. vol. vi. p. 424, 
pi. xiv. figs. 3, 4. — Kinderhook Limestone ; Iowa. 

Ctenacanthus sp>ectabilis, St. John & Worthen, op. cit. vol. vi. 
p. 420, pi. xv. fig. 1. — Kinderhook Limestone ; Iowa. 

Ctenacanthus triangularis, J. S. Newberry, Eep. Geol. Surv. Ohio, 
vol. i. (1873), pt. i. p. 329, pi. xxxvi. fig. 1.— Waverly 
Group ; Pennsylvania. (?) Carboniferous Limestone ; 
Mjatschkowa, Moscow (H. Trautschold, Nouv. Mem. Soc. 
Imp. Nat. Moscou, vol. xiv. 1879, p. 61, pi. vi. fig. 15). 

Ctenacanthus varians, St. John & Worthen, op. cit. vol. vi. p. 422, 
pi. xiv. fig. 2. — Kinderhook Limestone ; Iowa. 

Ctenacanthus vetustus, J. S. Newberry, op. cit. vol. i. pt. i. p. 326, 
pi. xxxv. fig. 3. — Huron Shale ; Ohio. [Columbia College, 
New York.] 

Ctenacanthus wrighti, J. S. Newberry, Thirty-fifth Rep. New 
York State Mus. (1884), p. 206, pi. xvi. figs. 12-14, and 
Palseoz. Fishes N. America (Mon. U.S. Geol. Surv. no. xvi. 
1889), p. 66, pi. xxvi. fig. 4. — Hamilton Group (Upper 
Devonian) ; Kashong Creek, New York. [Columbia College.] 



ICHTHY0D0RUL1TES. 105 

The so-called Ctenacanthns? faUacn, J. Leidy, MS. (figured in the 
Trans. Amer. Phil. Soc. vol. xi. 1857, pi. v. fig. 30), from the 
American Carboniferous Limestone, is founded upon an indetermin- 
able fossil in the Museum of the Academy of Sciences, Philadelphia. 

Spines differing only from Ctenacanthus in minor points have 
been named as follows : — 

Anaclitacanthus, St. John & Worthen (Pal. Illinois, vol. vi. 1875, 
p. 442), with the single species, A. semicostatus, St. John & Worthen, 
ibid. p. 443, pi. xvi. fig. 14. — Upper Burlington Limestone ; Iowa. 

Eunemacanthus, St. John & Worthen (ojo. cit. vol. vii. 1883, 
p. 246), with the single species, E. costatus, St. John & Worthen, 
ibid. p. 246, pi. xxiii. fig. 2, previously named Ctenacanthus? cos- 
tatus, Newberry & Worthen, Pal. Illinois, vol. ii. 1866, p. 120, 
pi. xii. fig. 5. — St. Louis Limestone; Illinois and Missouri. 



Genus HOMACANTHUS, Agassiz. 

[Poiss. Foss. Yieux Gres Eouge, 1845, p. 113.] 

Dorsal fin-spines of small size, slender, more or less arched, much 
laterally compressed, and gradually tapering distally ; sides of ex- 
serted portion ornamented with few, large, smooth, widely-spaced 
longitudinal ridges ; a similar ridge also forming a large anterior 
keel; posterior face with a double series of large, downwardly- 
curved denticles. * 



Homacanthus arcuatus, Agassiz. 
^ 1844. Hi/bodies gracilis, E. von Eichwald, Bull. Soc. Imp. Nat. Moscou, 
vol. xvii. p. 827. 
1845. Homacanthus arcuatus, L. Agassiz, op. cit. p. 113, pi. xxxiii. 

figs. 1-3. 
1860. Homacanthus gracilis, E. von Eichwald, Leth. Rossica, vol. i. 
p. 1600, pi. lv. fig. 9. 

The type species. 

Form. Sf Log. Devonian ; N.W. Russia. 

P. 2253. Fragment of spine. Egerton Coll. 

Homacanthus microdus, M'Coy. 

1848. Homacanthus microdus, F. M'Coy, Ann. Mag. Nat. Hist. [2] 

vol. ii. p. 115. 
1855. Homacanthus ?nicrodus, F. M'Coy, Brit. Palseoz. Foss. p. 633, 

pi. iii. k. fig. 19. 



L06 1CHTHY0D0RULITES. 

L888. Homacanthus microdus, J.W. Davis, Trans. Roy. Dublin Soc. [2] 
vol. i. p. 361, pi. xlviii. tigs. 7-9. 

Type. Woodwardian Museum, Cambridge. 

Form. Sf hoc. Lower Carboniferous Limestone ; Armagh, Ireland. 

P. 2516-18. Three spines, described and figured by J. W. Davis, 
loc. cit. EnnisTcillen Coll. 

P. 2515. Ten specimens, the majority very imperfect. 

Enniskillen Coll. 

The following specimens are somewhat smaller than H. mzcrodus, 
with more numerous longitudinal ridges than the foregoing : — , 

42258. Spine, imperfect distally und proximally; Carboniferous 
Limestone, Shropshire. Baugh Coll. 

P. 2247. Distal portion of spine, gently arched, with traces of 
well-developed posterior denticles, labelled Onchus subulatus 
in Agassiz's handwriting, and doubtless intended to be the 
type specimen of that species (named in Poiss. Foss. 
vol. iii. 1843, p. 177) ; Coal-Measures, Ruabon, Denbigh- 
shire. Egerton Coll. 

The following species has also been described : — 

Homacanthus macrodus, F. M'Coy, Ann. Mag. Nat. Hist. [2] 
vol. ii. (1848), p. 115, and Brit. Palseoz. Foss. (1855), 
p. 632, pi. iii.K. fig. 20 ; J. W. Davis, Trans. Roy. Dublin 
Soc. [2] vol. i. (1883), p. 362.— Lower Carboniferous 
Limestone; Armagh. [Woodwardian Museum, Cambridge.] 

Two spines from the St. Louis Limestone of Missouri and Illinois 
have also been described under the names of Homacanthus gibbosus, 
Newberry & Worthen (Pal. Illinois, vol. ii. 1866, p. 113, pi. xii. 
fig. 1), and H. ? rectus, Newberry & Worthen {ibid. p. 115, pi. xii. 
fig. 6). The former is now made the type of the genus Amacanthus, 
St. John & Worthen (Pal. Illinois, vol. vi. 1875, p. 464, pi. xxii. 
fig. 6), and the latter that of Marracanihus, St. John & Worthen 
(ibid. pp. 465, 466, pi. xxii. figs. 7-9). . 

The spine named Homacanthus gracilis, J. F. Whiteaves (Trans. 
Roy. Soc. Canada, vol. vi. sect. iv. 1*888, p. 96, pi. x. fig. 4), is also 
doubtfully determined, and may belong to an Acanthodian fish 
resembling Climatius. The type specimen was obtained from the 
Lower Devonian of Campbellton, New Brunswick, and is preserved 
in the Geological Survey Museum, Ottawa. 



IC IITI1 YODORULIXES . 



107 



Closely related to Homacanihus is the spine described as follows : — 

Hoplonchus, J. W. Davis (Quart. Journ. Geol. Soc. vol. xxxii. 
(1876), p. 336), with the type species, E. elegans, J. W. Davis, 
ibid. vol. xxxv. (1879), p. 183, pi. x. figs. 12-14.— Lower Coal- 
Measures ; Yorkshire. [J. W. Davis Collection, Halifax.] 

A second species is named H. ■parvulus, J. S. Newberry, Palaeoz. 
Fishes N. America (Mon. U.S. Geol. Surv. no. xvi. 1889), p. 169, 
pi. xxv. fig. 5. This spine was previously described as Ctenacanthus 
parvulus (J. S. Newberry, Eep. U.S. Geol. Surv. Ohio, vol, ii. pt. ii. 
1875, p. 55, pi. lix. fig. 3), and was obtained from the Cleveland 
Shale (Lower Carboniferous) of Ohio. 



Genus ACONDYLACANTHUS, St. John & Worthen. 
[Pal. Illinois, vol. vi. 1875, p. 432.] 

Dorsal fin-spines slender, elongated, laterally compressed and 
gradually tapering ; sides of exserted portion ornamented with lon- 
gitudinal ridges, usually smooth, rarely crenulated or denticulated ; 
posterior face concave, with a series of small denticles upon each 
margin, and sometimes with a median keel. 

As proved by specimens in the Collection (e. g. no. P. 2536 a) 
these slender spines have a short base of insertion, resembling that 
of Ctenacanthus. 

In their latest interpretation of this " genus," St. John & Worthen 
include in it Ctenacanthus-shsi^ed spines with smooth ridges, while 
long slender spines with denticulated ridges are placed in Ctena- 
canthus proper. We prefer, however, to follow Davis in regarding 
the form of the spine as the character of foremost importance. 

Acondylacanthus attenuatus, Davis. 

1883. Acondylacanthus attenuatus, J. W. Davis, Trans. Roy. Dublin 
Soc. [2] vol. i. p. 352, pi. xlvi. fig. 3. 

Type. Woodwardian Museum, Cambridge. 

Form. Sf Loc. Lower Carboniferous Limestone : Armagh, Ireland. 

P. 2672, P. 2674-5. Three imperfect distal portions of spines. 

Ennislcillen Coll. 



108 1C1ITHYODOKULITES. 

Acondylacanthus colei, Davis. 
[Plate I. fig. 2.] 

L888. Acondylacanthus colei, J. W. Davis, Trans. Roy. Dublin Soc. [2] 
vol. i. p. 347, pi. xlv. fig. 7, pi. xlvi. fig-. 1. 

Type. British Museum. 

Form. $ Loc. Lower Carboniferous Limestone ; Armagh. 

P. 2538. Type specimen, figured by Davis, loc. cit. pi. xlv. fig. 7. 

Enniskillen Coll. 

P. 2536. Ten more fragmentary spines. Enniskillen Coll. 

P. 2536 a. Fragment of crushed spine exhibiting the line of de- 
marcation between the exserted and inserted portions. 

Enniskillen Coll. 

P. 4199. Portion of spine showing well the median posterior keel. 

Enniskillen Coll. 

39167. Portion, of crushed spine, with lateral ridges partly nodose ; 
a transverse section is shown in PI. I. fig. 2. 

Bowerbank Coll. 



Acondylacanthus tenuistriatus, Davis. 

1888. Acondylacanthus tenuistriatus, J. W. Davis, Trans. Roy. Dublin 
Soc. [2] vol. i. p. 350, pi. xlv. fig. 8. 

Type. British Museum. 

Form. <$f Log. Lower Carboniferous Limestone : Armagh. 

P. 2890. Type specimen. Enniskillen Coll. 

P. 2890 a. More imperfect portion of spine. Enniskillen Coll. 

Acondylacanthus distans (M'Coy). 

1848. Ctenacanthus distans, F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. ii. 

p. 116. 
1855. Ctenacanthus distans, F. M'Coy, Brit. Palseoz. Foss. p. 625, 

pi. iii. k. fig. 15. 
1883. Acondylacanthus distans, J. W. Davis, Trans. Rov. Dublin Soc. 

[2] vol. i. p. 349, pi. xlvi. fig. 5. 

Type. "Woodwardian Museum, Cambridge. 

Form. Sf Log. Lower Carboniferous Limestone : Armagh. Car- 
boniferous Limestone ; Denbighshire. 



ICHTHYODORULITES. 109 

39917. Imperfect spine, 0*23 in length ; Denbighshire. 

Purchased, 1866. 

The following specimen may also be referred to Acondylacan- 
thus : — 

49652. Portion of an extremely compressed slender spine, with 
fine, smooth, superficial longitudinal ridges ; Upper 
Carboniferous Limestone, Richmond, Yorkshire. 

Purchased, 1878. 

The following species have also been ascribed to this genus : — 

Acondylacanthus cequicostatus , St. John & Worthen, Pal. Illinois, 
vol. vi. (1875), p. 434, pi. xvi. figs. 12, 13.— Keokuk 
Limestone ; Illinois. 

Acondylacanthus gracilis, St. John & Worthen, op. cit. vol. vi. 
p. 433, pi. xvi. figs. 8-11. — Kinderhook Limestone ; Iowa. 
[The type species.] 

Acondylacanthus jenkinsoni, St. John & Worthen, op. cit. vol. vi. 
p. 433; J. W. Davis, Trans. Eoy. Dublin Soc. [2] vol. i. 
p. 351, pi. xlvi. fig. 2 : Leptacanthus jenJcinsoni, F. M'Coy, 
Brit. Palaeoz. Foss. 1855, p. 633, pi. iii. o. figs. 14-16.— 
Carboniferous Limestone ; Lowick, Northumberland. 
[Woodwardian Museum, Cambridge.] 

Acondylacanthus junceus, St. John & Worthen, op. cit. vol. vi. 
p. 433 ; J. W. Davis, Trans. Eoy. Dublin Soc. [2] vol. i. 
p. 350, pi. xlvi. fig. 6 : Leptacanthus junceus, F. M'Coy, 
Ann. Mag. Nat. Hist. [2] vol. ii. (1848), p. 122, and Erit. 
Palaeoz. Poss. (1855), p. 633, pi. iii. g. fig. 13. — Carbon- 
iferous Limestone ; Derbyshire. [Woodwardian Museum.] 

Acondylacanthus occidentalis, St. John & Worthen, op. cit. vol. vi. 
p. 433 ; J. S. Newberry, Palasoz. Pishes N. America (Mon. 
U.S. Geol. Surv. no. xvi. 1889), p. 206, pi. xxv. fig. 6 : 
Leptacanthus ? occidentalis, Newberry & Worthen, Pal. 
Illinois, vol. ii. (1866), p. 116, pi. xii. fig. 2 : Ctenacanthus 
f/racillimus, Newberry & Worthen, ibid. p. 126, pi. xiii. 
fig. 3 ; St. John & Worthen, op. cit. vol. vii. (1883), p. 238, 
pi. xxiv. fig. 1. — St. Louis Limestone ; Missouri, Illinois, 
and Michigan. 

Acondylacanthus rectus, St. John & Worthen, op. cit. vol. vii. p. 241, 
pi. xxvi. fig. 2. — Upper Coal-Measures ; Illinois. 

Acondylacanthus remotus : Leptacanthus remotus, E. von Eichwald, 
Leth. Eossica, vol. i. (1860), p. 1601, pi. lvi. fig. 4.— 
Carboniferous Limestone; Kalouga, on Eiver Protva, 
Eussia. [University of St. Petersburg.] 



110 rCHTHTOBOETTLITBS. 

Acondylacanthus tenuistriatus, St. John & Worthen (non Davis), 
op. cit. vol. vi. p. 433 : Cladodus tenuistriatus, H. Roma- 
nowsky, Bull. Soc. Imp. Nat. Moscou, 1864, pt. ii. p. 167, 
pi. iv. fig. 33. — Carboniferous Limestone : Govt, of Toula. 

Acondylacanthus tuberculatus, J. W. Davis, Trans. Roy. Dublin 
' Soc. [2] vol. i. (1883), p. 348, pi. xlvi. fig. 4.— Lower 
Carboniferous Limestone : Armagh, \_0lim Enniskillen 
Collection; see Introduction.] 

Doubtful spines are also named Acondylacanthus ? mudgianus, 
St. John & Worthen (op. cit. vol. vii. p. 244, pi. xxiv. fig. 3), from 
the Upper Coal-Measures of Kansas : A. nuperus, St. John & Worthen 
(op. cit. vol. vii. p. 242, pi. xxvi. fig. 3), from the Upper Coal- 
Measures of Illinois ; and A. ? xiphias, St. John & Worthen {pp. cit. 
vol. vii. p. 244, pi. xxvi. fig. 1), from the Keokuk Limestone of 
Iowa. 



Genus ASTEROPTYCHIUS, M'Coy (ex Agassiz, MS.). 
[Ann. Mag. Nat. Hist. [2] vol. ii. 1848, p. 118.] 

Dorsal fin-spines slender, much laterally compressed, gradually 
tapering distally ; sides of exserted portion ornamented with few 
thread-like, longitudinal ridges, with broad striated interspaces, in 
which are scattered smooth tubercles ; posterior face concave, each 
margin having a series of large denticles in part directed upwards, 

Asteroptychius ornatus, M'Coy (ex Agassiz, MS.). 

1843. Asteroptychius ornatus, L. Agassiz, Poiss. Foss. vol. iii. p. 176 

(name only). 
(?) 1843. Asteroptychius poHlockii, L. Agassiz, ibid. p. 176 (name only). 
1848. Asteroptychius semiornatus, F. M'Coy, Ann. Mag. Nat. Hist. [2] 

vol. ii. p. 118. [Woodwardian Museum, Cambridge.] 
1855. Asteroptychius ornatus, F. M'Coy, Brit. Palaeoz. Foss. p. 615, 

pi. iii. k. figs. 23, 24. 
1855. Asteroptychius semiornatus, F. M'Coy, ibid. p. 616, pi. iii. k. fig. 22. 
1883. Asteroptychius ornatus, J. W. Davis, Trans. Roy. Dublin Soc. [2] 

vol. i. p. 353, pi. xlvi. figs. 7-9. * 

Type. Woodwardian Museum, Cambridge. 

The type species. 

Form. 6f Loc. Lower Carboniferous Limestone ; Armagh, Ireland . 

P. 2541-2. Twelve imperfect specimens. Enniskillen Cull. 



ICHTHYODORULTTES. 



Ill 



The following species have also been described, but there are no 
examples in the Collection :— 

Aster optychius bellulus, St. John & Worthen, Pal. Illinois, vol. vi. 

(1875), p. 439, pi. xvi. fig. 7. — Coal-Measures ; Illinois 

and Iowa. 
Aster optychius elecjans, J. S. Newberry, Palaeoz. Fishes N. America 

(Mon. U.S. Geol. Surv. no. xvi. 1889), p. 176, pi. xxv. 

fig. 4. — "Waverly Group (Lower Carboniferous); Michigan. 

[Columbia College, New York.] 
Aster optychius sancti-ludovici, St. John & Worthen, op. cit. vol. vi. 

p. 437, pi. xvi. figs. 3. 4. — St. Louis Limestone; Illinois 

and Missouri. 
Aster optychius triangularis, Newberry & Worthen, Pal. Illinois, 

vol. iv. (1870), p. 370, pi. ii. fig. 4. — Burlington Lime- 
stone; Illinois. 

Four doubtful, fragmentary spines are also named Aster optychius 
Iceokulc, St. John & Worthen (op. cit. vol. vi. p. 436, pi. xvi. fig. 2), 
from the Keokuk Limestone of Illinois ; A. tenellus, St. John & 
Worthen (op. cit. vol. vii. p. 248, pi. xxi. fig. 4), from the Upper 
Coal-Measures of Kansas ; A. ? tenuis, St. John & Worthen (op. cit. 
vol. vi. p. 438, pi. xvi. figs. 5, 6), from the Chester Limestone of 
Illinois ; and A. vetustus, St. John & Worthen (op. cit. vol. vi. p. 435, 
pi. xvi. fig. 1), from the Kinderhook Limestone of Iowa. 



Genus COSMACANTHUS, Agassiz. 
[Poiss. Foss. Vieux Gres Eouge, 1845, p. 120.] 

Syn. Geisacanthus, St. John & Worthen, Pal. Illinois, vol. vi. (1875), 
p. 440. 

Dorsal fin-spines of small size, slender, more or less laterally com- 
pressed and very slightly arched ; sides of exserted portion orna- 
mented with longitudinal series of ganoine-coated tubercles, and the 
anterior margin often keeled ; posterior face flat or concave, without 
lateral denticles, but sometimes with a median keel. 

The type species of this genus (0. malcolmsoni) is regarded by 
Pander 1 as founded upon a fragment of Placoderm armour ; and if 
this re-determination prove correct, the Carboniferous Ichthyodoru- 
lites recorded below must be named Geisacanthus. 

1 C. H. Pander, Placoderm. devon. Syst. 1857, p. 18. 



11 2 ICHTTIYODCmiTLTTES. 

Cosmacanthus marginalis, Davis. 

L888. Cosmacanthus marginalis, J. W. Davis, Trans. Roy. Dublin Soc. 
[2] vol. i. p. ooo, pi. xlviii. fig. 3. 

Type. British Museum. 

Form, 6f Loe. Lower Carboniferous Limestone: Armagh, Ireland. 

P. 2894. Type specimen. Ennishillen Coll. 

P. 2894 a. More complete but much abraded and broken spine. 

Ennishillen Coll. 

Cosmacanthus carinatus, Davis. 

1883. Cosmacanthus carinatus, J. W. Davis, Trans. Roy. Dublin Soc. 
[2] vol. i. p. 356, pi. xlviii. fig. 4. 

Type. British Museum. 

Form. Sf Loc. Lower Carboniferous Limestone : Armagh. 

P. 2893. Type specimen. Ennishillen Coll. 

Cosmacanthus priscus (M'Coy). 

1843. Leptacanthus priscus, L. Agassiz, Poiss. Foss. vol. iii. p. 176 

(name only). 
1848. Nemacanthus priscus, F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. ii. 

p. 120. 
1883. Cosmacanthus priscus, J. W. Davis, Trans. Roy. Dublin Soc. [2] 

vol. i. p. 358, pi. xlviii. figs. 1, 2. 

Type. Geological Society of London. 

Form. 4" Loc. Lower Carboniferous Limestone : Armagh. 

P. 2237. Fragment of spine. Eyerton Coll. 

The following species have also been described, but there are no 
examples in the Collection : — 

Cosmacanthus bidlatus : Geisacanihus bullatus, St. John & Worthen, 
Pal. Illinois, vol. vi. (1875), p. 441, pi. xvii. figs. 3, 4.— 
Lower Chester Limestone ; Illinois. 

Cosmacanthus carbonarius, F. M'Coy, Ann. Mag. Nat. Hist. [2] 
vol. ii. (1848), p. 119 ; J. W. Davis, Trans. Roy. Dublin 
Soc. [2] vol. i. (1883), p. 357. — Lower Carboniferous 
Limestone; Armagh. 

Cosmacanthus malcolmsoni, L. Agassiz, Poiss. Foss. Yieux Gres 
Rouge (1845), p. 121, pi. xxxiii. fig. 28.— Upper Old Red 
Sandstone ; Scat Craig, Elgin, Scotland. [The type 
species ; collection of James Powrie, Esq., Reswallie.] 



[CH TH YODORULIT ES . 113 

Cosmacanihus atellatus : Geisacantlms stellatus, St. John & 
Worthen, torn. cit. p. 440, pi. xxi. fig. 10. — Upper 
St. Louis Limestone; Missouri. [The type species of 
Geisacanihus.~\ 

Four other Lower Carboniferous genera of tuberculated spines, 
with a deep base of insertion, and probably for the most part 
bilaterally symmetrical, are also recognized, as follows : — 

BythiacantJius, St. John & Worthen (Pal. Illinois, vol. vi. 1875, 
p. 444), comprising B. van-hornei, St. John & Worthen (ibid. p. 445, 
pi. xvii. fig. 1), from the Upper St. Louis Limestone of Illinois ; and 
the so-called Asteracanihus siderius, J. Leidy, Proc. Acad. Nat. Sci. 
Philad. 1870, p. 13, and Ext. Vert. Fauna W. Territ. (Rep. U.S. 
Geol. Surv. Territ. vol. i. 1873), p. 313, pi. xxxii. fig. 59, probably 
from the St. Louis Limestone of Tennessee. [The second fossil, now 
in the Museum of the Academy of Sciences, Philadelphia, may 
be a broken piece of the abraded border of an Oracanthus-shsi^ed 
spine.] 

Glymmatacanthus, St. John & Worthen (op. cit. vol. vi. p. 446), 
comprising G. irishi, St. John & Worthen (ibid. p. 447, pi. xvii. 
fig. 2), from the Upper Kinderhook Limestone of Iowa; G. petro- 
doides, St. John & Worthen (op. cit. vol. vii. 1883, p. 250, pi. xxv. 
fig. 2), from the Chester Limestone of Illinois ; and G. rudis, St. John 
& AVorthen (op. cit. vol. vii. p. 249, pi. xxv. fig. 1), from the Keokuk 
Limestone of Iowa. 

Thaumatacanthus, W. Waagen, Salt-Eange Fossils (Pala3ont. 
Indica, ser. 13), vol. i. (1880), p. 78, with the single species, 
T. blanfordi, Waagen (ibid. p. 79, pi. viii. fig. 1), from the Upper 
Productus Limestone of Kiri, in the Salt Eange, Punjab, India. 
[Indian Museum, Calcutta.] 

CJialazacantJms, J. W. Davis, Trans. Roy. Dublin Soc. [2] vol. i. 
(1883), p. 370, with the single species C. verrucosus, Davis (ibid. 
p. 371, pi. xlviii. fig. 13), from the Lower Carboniferous Limestone 
of Bristol. [Bristol Museum.] 



Genus LISPACANTHUS, Davis. 

[Trans. Roy. Dublin Soc. [2] vol. i. 1883, p. 359.] 

Dorsal fin-spine of medium size, slender, laterally compressed, and 
gradually tapering ; sides of exserted portion apparently smooth ; 
posterior face with a median longitudinal keel, but no denticles ; 
base-line of exserted portion very oblique. 

PART II. I 



114 H'llTliYODOKULlTES. 



Lisp acanthus retrogradus, Davis. 

18S3. Lispaeanihus retrogradus, J. W. Davis, torn. cit. p. 359, pi. xlviii. 
fig. 6. 

Type. British Museum. 

The type species. 

Form. $ Loc. Lower Carboniferous Limestone : Armagh. 

P. 2544. Type specimen. The smoothness of the exserted portion 
may be due to abrasion, but at present there is no decided 
evidence of this. Ennishillen Coll. 

The following spine is also doubtfully placed here : — 

Lispaeanihus gracilis, J. W. Davis, torn. cit. p. 359, pi. xlviii. 
fig. 6. — Carboniferous Limestone ; Kendal Pells, West- 
moreland. [Mus. Geol. Soc. London.] 



Genus LEPRACANTHUS, Owen. 
[Geol. Mag. vol. vi. 1869, p. 481.] 

Dorsal fin-spines of small size, slender, much laterally compressed, 
and gently arched ; sides of exserted portion ornamented with lon- 
gitudinal series of large ganoine-coated tubercles, almost pear-shaped 
or comma-shaped and connected in the distal portion of the spine, 
but becoming obliquely oval and well separated proximally ; anterior 
margin keeled ; posterior face with few large slender denticles. 

Lepracanthus colei, Owen. 

[Plate I. fig. 1.] 

1843. Lepracanthus colei, Sir P. Egerton, in Agassiz, Poiss. Foss. vol. iii. 

p. 177 (name only). 
1869. Lepracanthus colei, R. Owen, Geol. Mag. vol. vi. p. 481, woodc. 
1876. Lepracanthus colei, J. W. Davis, Quart. Journ. Geol. Soc. vol. 

xxxii. p. 335. 

Type. British Museum. 
The type species. 

Form. 6f Loc. Coal-Measures : N. Wales, Yorkshire, and Lanark- 
shire. 

P. 2861, P. 615. Type specimen and counterpart., shown somewhat 
enlarged and restored in the accompanying woodcut (fig. 9) : 
Euabon, Denbighshire. The posterior denticles are well 
preserved. Enniskillen <$f Egerton Colls. 



ICHTHYODORULITES. 115 

P. 2233. JSpine and fragment, the former exhibiting the lateral 
ornament and anterior keel ; Lower Coal-Measures, Low- 
moor, Yorkshire. The spine is shown, of natural size, in 

Fig. 9. 



Lepracantkus cold, Owen. Coal-Measures, Kuabon. [P. 2861.] 

Plate I. fig. 1, and a portion of the ornament is enlarged 
four times in fig. 1 a. Egerton Coll. 

P. 2902. More arched spine ; Lowmoor. Enniskillen Coll. 



Genus NEMACANTHUS, Agassiz. 

[Poiss. Foss. vol. iii. 1837, p. 25.] 

Syn. Desmacanthus, F. A. Quenstedt, Der Jura, 1858, p. 34. 

Dorsal fin-spines of small or moderate size, much laterally com- 
pressed, nearly straight ; sides of exserted portion marked with fine 
longitudinal striae, thus not sharply separated from the inserted 
portion, though exhibiting large, rounded, ganoine- coated tubercles, 
in longitudinal series, covering a variable extent ; anterior margin 
prominently keeled ; posterior face with a row of small pointed 
denticles upon each edge. 

i2 



1 L6 lOimiYonoiiuLiTES. 

The Rhaetic spines assigned to this genus are not improbably 
referable to the dorsal iins of the fish of which the teeth are known 
as Hybodus minor K 



Nemacanthus monilifer, Agassiz. 

1837. Ne7)iaccmthus monilifer, L. Agassiz, Poiss. Foss. vol. iii. p. 26, 

pi. vii. figs. 10-15. 
1837. Nemacanthus Jllifer, L. Agassiz, ibid. p. 26, pi. vii. fig. 9. 

[Bristol Museum.] 
(?)1844. Nemacanthus monilifer and N. Jilifer, Meyer & Plieninger, 

Beitr. Pal. Wiirttembergs, p. 108, pi. xii. figs. 65, 66. 
1858. Desmacanthus cloacinus, F. A. Quenstedt, Der Jura, p. 34, pi. ii. 

fig. 13. [Type of Desmacanthus, Tubingen Museum.] 
1874. Nemacanthus monilifer, K. Martin, Zeitschr. deutsch. geol. Ges. 

vol. xxvi. p. 820. 
1881. Nemacanthus monilifer, J. W". Davis, Quart. Journ. Geol. Soc. 

vol. xxxvii. p. 418. 
1881. Nemacanthus filifer, J. W. Davis, ibid. p. 418. 

Type. British Museum. 
The type species. 

Form. Sf Log. Rhsetic : Gloucestershire, Somersetshire, Devonshire, 
and Leicestershire ; Wiirtemberg. 

23153 b. Two fragments ; Aust Cliff, near Bristol. Purchased, 1849. 

23812. Five portions of spines ; Aust Cliff. Purchased, 1849. 

24840. Bone-bed with fragments of three spines ; Aust Cliff. 

Purchased, 1850. 

43852. Four fragments ; Aust Cliff. Purchased, 1872. 

44835. Portion of large spine ; Aust Cliff. 

Presented by Benjamin Bright, Esq., 1873. 

46830. Small spine ; Aust Cliff. By transfer, 1875. 

P. 2217. Six portions of spines, two being associated; Aust Cliff. 

Egerton Coll. 

P. 2852. Two fragments ; Aust Cliff. Ennishillen Coll. 

P. 2854. Small spine ; Somersetshire. EnnisTcillen Coll. 

P. 2853. Nearly complete small spine ; Axminster. 

Enniskillen Coll. 

1 A. S. Woodward, Trans. Leicester Lit. & Phil. Soc. n. s. pt. xi. (1889), 
p. 18. 



ICHTHYOBOEULTTES. 117 



Nemacanthus brevis, Phillips. 

..843. Nemacanthus brevispinus, L. Agassiz, Poiss. Foss. vol. iii. p. 17? 

(name only). 
1871. Nemacanthus brevis, J. Phillips, Geol. Oxford, p. 178, diagr. 

xxxviii. figs. 3-5. 
1890. Nemacanthus brevis, A. S. Woodward, Proc. Geol. Assoc, vol. xi. 

p. 289, pi. iii. fig. 1. 

Type. Oxford Museum. 

Form. <$f Log. Bathonian (Stonesfield Slate) : Stonesfield, Oxford- 
shire. 

P. 2218. Two specimens, one figured by the present writer, he. cit. 
pi. iii. fig. 1. Egerton Coll. 

P. 2851. Two specimens. Enniskillen Coll. 

The following species have also been determined : — 

Nemacanthus granulosus, Minister, in L. Agassiz, Poiss. Foss. 
vol. iii. (1843), p. 177 (name only) ; (?) F. von Alberti, 
Ueberblick liber die Trias (1864), p. 208, pi. vii. fig. 9.— 
Muschelkalk ; Laineck, Bavaria. 

Nemacanthus minor, J. W. Davis, Quart. Journ. Geol. Soc. vol. 
xxxvii.(1881), p. 419, pi. xxii. fig. 5. — Bhaetic; Wainlode 
Cliff, Gloucestershire. [Mus. Geol. Soc. London.] 

Nemacanthus sentionis, Miinster, in Agassiz, Poiss. Foss. vol. iii. 
(1843), p. 177 (name only). Quoted as N. senticosus by 
C. G. Giebel, Fauna der Yorwelt, vol. i. (1848), Fische, 
p. 304. — Muschelkalk ; Laineck, Bavaria. 

Nemacanthus tuber culatus, F. Bassani, Atti Soc. Ital. Sci, Nat. 
vol. xxix. (1886), p. 30. — Upper Trias ; Besano, Lom- 
bardy. 

The following spine may also be referable to this group of 
Ichthyodorulites : — 

Psilacanthus aalensis, F. A. Quenstedt, Der Jura (1858), p. 347, 
pi. xlvii. fig. 20. — Brown Jura /3 ; Aalen, Wiirtemberg. 
[Tiibingen University Museum.] 



1 IS ICHTHYODORULTJ B8. 



II. Slender elongated spines, bilaterally symmetrical, with the 
internal cavity only open at the extremity of the base, and 
little or no smooth inserted portion. 



Genus GNATHACANTHUS, Davis. 
[Trans. Boy. Dublin Soc. [2] vol. i. 1883, p. 363.] 

Spine laterally compressed, with one margin acute, the other flat- 
tened ; sides ornamented with longitudinal ridges, smooth or tuber- 
culated ; acute margin with a single series of large denticles, flattened 
margin with a double series of smaller denticles. 

The base of the spine is unknown, and Gnathacanthus is thus only 
provisionally placed in this group of Ichthyodorulites. 

Gnathacanthus triangularis, Davis. 

1883. Gnathacanthus triangularis, J. W. Davis, torn. cit. p. 363, pi. xlviii. 
fig. 11. 

Type. British Museum. 

The type species. 

Form. Sf Log. Lower Carboniferous Limestone : Armagh. 

P. 2891. Type specimen. Enniskillen Coll. 



Gnathacanthus striatus, Davis. 

1883. Gnathacanthus striatus, J. W. Davis, torn. cit. p. 364, pi. xlviii. 
fig. 12. 

Type. British Museum. 

Form. $ Log. Lower Carboniferous Limestone : Armagh. 

P. 2892. Type specimen. Enniskillen Coll. 

P. 2892 a. Fragment. Enniskillen Coll. 



Genus APATEACANTHUS, nov. 

Spine elongated, slender, very gradually tapering, extremely com- 
pressed laterally ; sides ornamented with irregular series of tuber- 
culations ; posterior border with one (? or two) close series of acute, 
hook-shaped, downwardly-pointing denticles. 



ICHTHYOTKlftTTTJTES. 110 

Apateacanthus vetustus (Clarke). 

1885. Pristacanthus vetustus, J. M. Clarke, Bull. U.S. Geol. Surv. 
no. 16, p. 42, pi. i. fig. 7. 

Type. National Museum, "Washington. 

The type species. Known only by the type specimen, which is very 
suggestive of a Chimseroid dorsal fin-spine, and certainly pertains to 
a hitherto unrecognized genus, as already suggested by J. S. New- 
berry, Palseoz. Pishes N. America (Mon. U.S. Geol. Surv. no. xvi. 
1889, p. 61). 

Form. 6f Log. Upper Devonian (Naples Shales) : Yates Co., New 
York. 

Not represented in the Collection. 

Genus PRISTACANTHUS, Agassiz. 

[Poiss. Poss. vol. iii. 1837, p. 35.] 

Spine very long, slender, and gradually tapering, extremely com- 
pressed laterally, with acute anterior and posterior margins ; sides 
smooth, a longitudinal band of gano-dentine covering the anterior 
half ; a single series of large, compressed, triangular denticles upon 
the posterior margin. 

Pristacanthus securis, Agassiz. 

1825. " Defense caudale," E. Deslongchanips, Mem. Soc. Linn. Nor- 

mandie, vol. ii. p. 271, figs. 1-3. 
1837. Pristacanthus securis, L. Agassiz, Poiss. Foss. vol. iii. p. 35, 

pi. viii. a. figs. 11-13. 
1871. Prist acatithus securis, J. Phillips, Geol. Oxford, p. 178, diagr, 

xxxviii. fig. 10. 
1890. Pristacanthus securis, A. S. Woodward, Proc. Geol. Assoc, vol. xi. 

p. 290, pi. iii. fig. 2. 

Type. Caen Museum, and Royal College of Surgeons, London. 
The type species. 

Form. &f Log. Great Oolite : Caen, Normandy. Stonesfield Slate : 
near Oxford. 

P. 6253. Crushed specimen showing internal cavity; Allemagne, 
near Caen. Purchased. 

32726-27. Two specimens, one showing the imperfect tapering 
distal portion, the other exhibiting the characteristic lateral 
band of gano-dentine ; Allemagne. Tesson Coll. 

41306. Imperfect distal portion of spine ; Allemagne. 

Purchased, 1869. 



1 20 I0HTHYODOKULITE8. 

P. 6254. Two specimens ; Allemagne. EnnisMJen Coll. 

A fragment of an Asterolepid appendage from the Devonian of 
Russia has been erroneously assigned to this genus under the name 
of Pristctcanthus marinus, E. von Eichwald (Bull. Soc. Imp. Nat. 
Moscou, vol. xvii. 1844, p. 826 (marianus), and ibid. vol. xix. 1846, 
pt. ii. p. 294, pi. x. figs. 10, 11, and Leth. Eossica, vol. i. 1860, 
p. 1605). 

Genus CCELORHYNCHUS, Agassiz. 
[Poiss. Foss. vol. v. pt. i. 1844, p. 92.] 

Syn. Cylindracanthus, J. Leidy, Proc. Acad. Nat. Sci. Philad. 1856, 
p. 12. 

Spine very long, slender, and gradually tapering, rounded in sec- 
tion, and without denticles ; external surface longitudinally ridged 
and grooved, each ridge corresponding to a wedge-shaped plate, 
which forms a small sector of the spine. Central cavity -relatively 
small, sometimes in part simple, but usually divided by a median 
partition; a division plane passing through the middle of the 
partition, thus allowing the spine to be readily split into two sym- 
metrical halves. 

This ichthyodorulite was originally mistaken by Agassiz for the 
rostrum of a Xiphioid Teleostean, and its truly dermal nature was 
first demonstrated by W. C. Williamson \ A Cretaceous example 
in the Willett Collection, Brighton Museum, suggests that the fossil 
may be referable to an undetermined Chimasroid 2 . 

Ccelorhynchus rectus, Agassiz. 

1784. " Petrification inconnue," Burtin, Oryctogr. Bruxelles, pi. vi. 

figs. A-E. 
1844. Ccelorhynchus rectus, L. Agassiz, Poiss. Foss. vol. v. pt. i. p. 92 

(name only). 
1850. Ccelorhynchus, F. Dixon, Foss. Sussex, p. 112, pi. x. figs. 14-17, 

pi. xi. fig. 26. 
1861. Ccelorhynchus rectus, R. Owen, Palaeontology, ed. 2, p. 172, 

woodc. fig. 80. 
1871. Ccelorhynchus burtini and C. rectus, H. Le Hon, Prelim. Mem. 

Poiss. Tert. Belg. p. 14. 
1871. Ccelorhynchus burtinii and C. rectus, P. J. Van Beneden, Bull. 

Acad. Roy. Belg. [2] vol. xxxi. p. 500. 



1 Pbil. Trans. 1849, p. 471, pi. xliii. figs. 35-37, and ibid. 1851, p. 667. 

2 A. S. Woodward, Ann. Mag. Nat. Hist. [6] vol. ii. (1888), p. 223. 






ICHTHYODORULITES. 121 

1874. Ccelorhynchus rectos and C. burtini, T. C. Winkler, Archiv. Mus. 

Teyler, vol. iii. p. 303. 
1879. Cazlorhynchus rectus, A. de Zigno, Mem. R. Istit. Veneto, vol. xxi. 

p. 784, pi. xv. figs. 16-18. 

Type. British Museum. 

The type species, attaining a length of not less than 0*45, with a 
maximum diameter of about (VOlS. The superficial longitudinal 
ridges are normally very sharp, their broad and flat appearance in 
many fossils being due to post-mortem abrasion. 

Form. § Loc. London Clay : Isle of Sheppey. Bracklesham Beds : 
Sussex. Barton Clay : Hampshire. Middle and Upper Eocene : 
Belgium and Italy. Derived in Red Crag : Suffolk. 

38881. Two portions of spines ; London Clay, Sheppey. 

Bowerbank Coll. 

25859. One of the type specimens, much abraded, figured by Dixon, 
op. cit. pi. xi. fig. 26 ; Bracklesham. Dixon Coll. 

25729. Four specimens, three showing the distal extremity in which 
the degree of tapering and bluntness varies considerably ; 
Bracklesham. Dixon Coll. 

40276. Fragments ; Bracklesham. Edwards Coll. 

P. 1766-67. Similar specimens ; Bracklesham. Egerton Coll. 

P. 5438. Similar specimens ; Bracklesham. 

Presented by P. E. Coombe, Esq., 1888. 

P. 3941. Imperfect spine 0*375 in length, wanting both extremities ; 
Bracklesham. Enniskillen Coll. 

30890. Portion of small spine ; Bramshaw. Purchased. 

P. 4304. Fragments ; Barton Clay, Barton Cliff. Enniskillen Coll. 

42880. Numerous fragments ; Brussels. Van Breda Coll. 

P. 4305. Fragment ; Brussels. Enniskillen Coll. 

43312. Two fragments; Red Crag, Woodbridge. Whincopp Coll. 

The following specimens are probably portions of the base of large 
examples of C. rectus, but the longitudinal ridges of the first two 
exhibit a certain degree of sinuosity, and they may thus be of the 
form named C. sinuatus by Agassiz (Poiss. Foss. vol. v. pt. i. 1844, 
p. 92), without description : — 

P. 6232. Well-preserved specimen ; London Clay, Isle of Sheppey. 

History unknown. 



1 22 TCHTHY0D0RFLITE8. 

P. 4303. Two smaller and more imperfect fragments : Sheppey. 

EnnisJcillen Coll. 

Cceiorhynchus gigas, A. S. Woodward. 
1888. Cceiorhynchus gigas, A. S. Woodward, Ann. Mag. Nat, Hist, [6] 
vol. i. p. 225. 

Type. British Museum. 
Form. 4' Loc. Eocene : Egypt. 

893-5. Type specimen, in three fragments, described loc. cit. ; from 
the rock of the Great Sphinx. 

Presented by Col. Howard Vyse. 

Cceiorhynchus cretaceus, Dixon. 

1850. Cceiorhynchus cretaceus, F. Dixon, Geol. Sussex, pi. xxxii. fig. 10. 
1888. Cceiorhynchus cretaceus, A. S. Woodward, Proc. Geol. Assoc, 
vol. x. p. 330, and Ann. Mag. Nat, Hist. [6] vol. ii. p. 225. 

Type. Brighton Museum. 

Form. Sf Loc. Upper Chalk : Sussex and Norfolk. 

P. 3942. Imperfect typical specimen ; (?) Sussex. Enniskillen Coll. 

48956 a. Fragment ; Norwich. Bayfield Coll. 

The genus is represented from other localities as follows : — 

P. 5838. Fragment ; Craie de Ciply, Belgium. 

Presented by M. Houzeau de Lehaie, 1888. 

41860. Abraded fragment ; " Eocene, Gerona, Spain." 

Presented by S. P. Pratt, Esq., 1870. 

P. 1769. Several fragments, probably of the form named Cylindra- 
canthus ornatus by J. Leidy, Proc. Acad. Nat. Sci. 
Philad. 1856, p. 12, and subsequently {ibid. p. 302) 
assigned by that author to Cceiorhynchus ; Eocene, Clarke's 
Co., Alabama, U.S.A. Egerton Coll. 

23284. Impression of part of spine, noticed by Lydekker, Bee. Geol. 
Surv. India, vol. xx. (1887), p. 70; probably from the 
Middle Eocene (Nummulitic Series) of Sind, India. 

The following species has also been described, but there are no 
examples in the Collection : — 

CcrlorhyncJius sulcatus, K. E. Schafhautl, Siid-Bayerns Leth. 
Geogn. (1863), p. 249, pi. lxiv. fig. 5. — Eocene ; Kressen- 
berg, Bavaria. [Munich Museum.] 



ICHTHYODOTtTTLTTES. 1 23 

III. Paired spines of which some may have been placed in front of 
fins, but of which many are broad, with insignificant base of 
insertion, and must have been arranged as independent dermal 
armour. 

Genus MACH5IRAC ANTHUS, Newberry. 

[Bull. National Institute, 1857, p. 6.] 

Syn. Machcerius, M t Renault, Comptes Rendus, vol. xlvii. 1858, p. 102 
(preoccupied). 

Spines, so far as known, elongated, tapering, more or less curved, 
and somewhat laterally compressed, with sharp edges and a large 
longitudinal ridge on each side ; central cavity extending nearly to 
the apex ; external surface covered with a thin layer of gano- 
dentine, smooth, finely punctate, or longitudinally striated. 

Machseracanthus sulcatus, Newberry. 

1843. "Ichtkyodorulite," J. Hall, Nat. Hist. New York, pt. iv. p. 174, 

woodc. fig. 69. 
1857. Machcer acanthus sulcatus, J. S. Newberry, Bull. Nat. Inst. p. 6. 
1870. Machairacanthus sulcatus, E. R. Lankester, Geol. Mag. vol. vii. 

p. 398, woodc. fig. 3. 
1873. Machceracantlius sulcatus, J. S. Newberry, Rep. Geol. Surv. Ohio, 

vol. i. pt. ii. p. 305. 
1886. Machceracantlius sulcatus, T. H. Lennox, Proc. Canad. Inst. 

vol. iii. p. 120. 
1889. Machcer acanthus sulcatus, J. S. Newberry, Paheoz. Fishes N. 

America (Mon. U.S. Geol. Surv. no. xvi.), p. 40, pi. xxix. fig. 5. 

Type. Delaware University, Ohio. 

lorm. Sf Loc. Lower Devonian (Corniferous Limestone) : Ohio, 
New York, Ontario, and Canada. 

P. 6216. Impression of part of spine, apparently the specimen 
figured by Lankester, loc. cit. ; Gaspe, Canada. 

Presented by Sir J. William Dawson, K.C.M.G., 1890. 

The following species are also recognized, but there are no 
examples in the Collection : — 

Maclicer 'acanthus abnormis : Ctenacanthus abnormis, C. G. Giebel 
Abh. Naturw. Yereins Provinz Sachsen u. Thiiringen, vol. i. 
(1858), p. 264, pi. i. fig. 12 ; J. Barrande, Syst. Silur. 
Boheme, Suppl. to vol. i. (1872), p. 628 : E. Kayser, Abh. 
geol. Specialk. Preuss. u. Thiiring. Staaten, vol. ii. pt. iv. 



124 h n rHTODORULITES. 

( 1 8 78), p. 3, pi. i. fig. 19: (^)Ichthy odontites, F. A. Roemer, 
Palaontogr. vol. iii. (1852), p. 75, pi. xi. fig. 26. — Lower 
Devonian ; Harz Mts. 

Machasracanihus archiaci : Machcerius archiaci, M. Rouanlt, 
Comptes Rendus, vol. xlvii. (1858), p. 103. — Lower De- 
vonian; Brittany. 

MaeJuvmcanthus bohemicus, 0. Novak, Sitzungsb. k. bbhm. Gesell. 
Wiss. 1886 (1887), p. 663, pi. i. fig. 14: Ctenacanthus 
bohemicus, J. Barrande, Syst. Silur. Boheme, Suppl. to 
vol. i. (1872), p. 641, pis. xxviii., xxx., xxxiv. : Machcera- 
canthus, E. Kayser, Neues Jahrb. 1884, vol. ii. p. 82. — 
Lower Devonian ; Bohemia. [Royal Bohemian Museum, 
Prague.] 

Machceracanthus larteti: Machcerius larteti, M. Rouault, torn. cit. 
(1858), p. 102. — Lower Devonian ; Brittany. [Type 
species of Machcerius. ,] 

Machceracanthus major, J. S. Newberry, Bull. Nat. Inst. (1857), 
p. 6, and Rep. Geol. Surv. Ohio, vol. i. pt. ii. (1873), 
p. 304, pi. xxv. fig. 2, and Palseoz. Fishes N. America 
(1889), p. 39, pi. xxix. fig. 4. — Lower Devonian (Corni- 
ferous Limestone) ; Ohio. [Columbia College, New York.] 

Machceracanthus peracutus, J. S. Newberry, torn. cit. (1857), p. 6, 
and torn. cit. (1873), pp. 303, 305, pi. xxix. fig. 6, and 
woodc, and torn. cit. (1889), pp. 38, 40, pi. xxix. fig. 6, 
and woodc. — Corniferous Limestone ; Ohio. [The type 
species. Columbia College, New York.] 



Genus HAPLACANTHUS, Agassiz. 
[Poiss. Foss. V. G. R. 1845, p. 114.] 

Spines of small size, elongated, tapering, more or less curved and 
laterally compressed, apparently without posterior denticles ; a deep 
longitudinal groove separating a yarrow anterior rim from the rest 
of the spine, which has smooth sides or exhibits faint longitudinal 
striae. 

As remarked by von Eichwald, spines of this form may be com- 
pared with those of Cheiracanthus and allied Acanthodian genera. 

Haplacanthus marginalis, Agassiz. 

1845. Haplacanthus marginalis, L. Agassiz, Poiss. Foss. V. G. R. p. 114, 
pi. xxxiii. figs. 4-6. 

1846. Onchus tenuisulcatus, E. von Eichwald, Bull. Soc. Imp. Nat. 
Moscou, vol. xix. pt. ii. p. 292, pi. x. figs. 6, 7. 



TCHTTIYODORULITES. 



125 



1860. Haplacanthus tenuisulcatus, E. von Eichwald, Leth. Rossica, 
vol. i. p. 1599, pi. lvii. fig. 19. 

The type species. 

Form, fy Log. Devonian : near St. Petersburg. 

P. 2252. Fragment of spine. Egerton Coll. 

Genus HETER ACANTHUS, Newberry. 

[Palseoz. Pishes N. America (Mon. U. S. Geol. Surv. no. xvi. 
1889), p. 65.] 

Spines small or of moderate size, much laterally compressed, broad 
and triangular, and gently arched ; internal cavity very large, 
opening by a long fissure at the convex border ; base of insertion 
short or absent. Sides of exserted portion ornamented with broad, 
flattened, smooth, longitudinal ridges, bifurcating and intercalated 
towards the base ; the ridges having finely crenulated margins, 
separated by very narrow, fissure-like sulci. 

Keter acanthus politus, Newberry. 

1889. Heteracanthus politus, J. S. Newberry, torn. cit. p. 66, pi. xxi. 
figs. 4, 5. 

Type. Columbia College, New York. 
The type species, not represented in the Collection. 
Form. 6f Log. Hamilton Group (Upper Devonian) : Milwaukee, 
Wisconsin. 

Heteracanthus heterogyrus (Agassiz). 

[Plate III. fig. 6.] 

1845. Onchus heterogyrus, L. Agassiz, Poiss. Foss. V. G. R. p. 117, 
pi. xxxiii. figs. 16-18. 

Type. Unknown. 

This species is assigned to Heteraeanihus on account of the 
characters of the superficial ornamentation. Both the type specimen 
and the example recorded below appear to be fragmentary, thus not 
exhibiting the original form of the spine. 

Form. &f Log. Devonian : N.W. Russia. 

P. 2248. Fragment of spine, partly shown, of twice the natural 
size, in PI. III. fig. 6. The ornament is precisely similar 
to that of the type species, which the writer has examined 
at Columbia College. Egerton Coll. 



126 



TOHTHYOnOKFLITES. 



Genus PSAMMOSTEUS, Agassiz. 

[Poiss. Fobs. V. G. E. 1845, p. 103.] 

Bjn. Placosteus, L. Agassiz, Poiss. Foss. vol. i. 1844, p. xxxiii (name 
only). 
Psammolepis, L. Agassiz, ibid. p. xxxiv (name only). 

Spines and dermal plates of moderate size, the former much 
laterally compressed, usually unsymmetrical, broad and triangular, 
with a large internal cavity and short base of insertion. External 
surface ornamented with numerous, closely arranged, rounded or 
elongated tubercles of gano-dentine, usually stellate and rarely 
arranged in regular series. 

As pointed out by Agassiz and Pander, the histological structure 
of these ichthyodorulites is suggestive of that of Selachian dermal 
armour ; and in external characters they are most nearly paralleled 
by Oracanthus, as described below. 

Psammosteus mseandrinus, Agassiz. 

1844. Placosteus m<sandrinus, L. Agassiz, Poiss. Foss. vol. i. p. xxxiii 
(name only). 

1845. Psammosteus mceandrinus, L. Agassiz, Poiss. Foss. V. G. R. 
p. 104, pi. xxvii. figs. 5, 6. 

1845. Ctenacanthus serrulatus, L. Agassiz, ibid. p. 119, pi. xxxiii. fig. 24. 

1857. Aster olepis ?, C. H. Pander, Placoderm. devon. Syst. p. 20, pi. vii. 
figs. 16-18. 

1858. Psammosteus m&andrinus, G. Kade, Programm k. Realschnle zu 
Meseritz, p. 11, figs. 2-5. 

1860. Psammosteus mceandrinus, E. von Eichwald, Leth. Eossica, vol. i. 

p. 1516. 
1880. Coccosteus megalopteryx, H. Trautschold (error e), Verhandl. russ. 

k. mineral. Gesell. St. Petersburg, p. 152, pi. vi. fig. 1, pi. vii. fig. 2. 

1889. Coccosteus megalopteryx, H. Trautschold (errore), Zeitschr. 
deutsch. geol. Gesell. vol. xli. p. 36. 

1890. " Selachian appendages," E. H. Traquair, Ann. Mag. Nat. Hist. 
[6] vol. v. p. 134. 

Type. Unknown. 
The type species. 
Form. &( Loc. Devonian : N.W. Eussia. 

P. 4493. Two spines, imperfect distally, of the form assigned to 
this species by Eichwald, but described as Coccosteus 
meg alopter yoc by Trautschold ; from banks of Eiver Ssjass. 
In one specimen there are indications of a narrow inserted 
portion at the base of one side and a much deeper insertion 



ICHTHYODORULITES. 127 

on the opposite side ; but this feature may possibly be due 
in part to accidental abrasion towards the proximal end. 
The convex border of the spine exhibits evidence of wear 
during life, the ornament having been destroyed. 

Purchased, 1884. 

35019, a, b. Three fragmentary, short, blunt spines, of a type 
different from the above, but closely resembling the latter 
in ornamentation : from a boulder of Old Red Sandstone, 
Birnbauin, near Posen, Silesia. The first of the specimens 
agrees with the spine shown in Pander's fig. 16. 

Purchased, 1860. 

P. 2229. Impression of ornament and some small fragments in 
matrix; Livonia. Egerton Coll. 

Psammosteus arenatus, Agassiz. 

1844. Placosteus arcuatus, L. Agassiz, Poiss. Foss. vol. i. p. xxxiii 
(name only). 

1845. Psammosteus arenatus, L. Agassiz, Poiss. Foss. V. G. R. p. 105, 
pi. xxxi. figs. 7-10. 

1857. " Ichthyodorulith," C. H. Pander, Placoderm. devon. Syst. p. 102, 
pi. vii. fig. 22. 

1858. Psammosteus arenatus, G. Kade, Programm k. Realschule zu 
Meseritz, p. 10, fig. 14. 

Type. Unknown. 

By Eichwald (Leth. Rossica, vol. i. p. 1510) the plates thus 
described are doubtfully associated with the so-called Asterolepis 
depressus ; while the triangular spine figured by Pander is ascribed 
to Coccosteus megalo_pteryx by Trautschold (Zeitschr. deutsch. geol. 
Gesell. vol. xli. p. 36). 

Form, St Loc. Devonian : IST.W. Russia and N. Scotland. 

35019 C. Fragment from boulder at Birnbaum, near Posen, Silesia. 

Purchased, 1860. 

P. 6233. Portion of typical plate ; Riga. 

Presented by Sir JR. I. Murchison, K.C.B. 

P. 709. Fragment in matrix ; Riga. Egerton Coll. 

P. 4598. Similar, but larger fossil ; Riga. EnnisJcillen Coll. 

42453. Two portions of plates said to have been obtained from the 
Caithness Flagstones of Wick. In physical characters 
one example much resembles that presented by Sir R. I. 
Murchison. Peach Coll. 



L28 ICHTHYODORTJLITES. 

Psammosteus paradoxus, Agassiz. 

L844. Psammolepis paradoxus, L. Agassiz, Poiss. Foss. vol. i. p. xxxiv. 

(name only). 
1845. Psammosteus paradoxus, L. Agassiz, Poiss. Foss. V. G. P. 

p. 104, pi. B. figs. 5, 6, pi. xxvii. figs. 2-4. 

Type, Unknown. 

Form. Sc Loc. Devonian : N.W. Pnssia. 

P. 4491. Much abraded plate, with surface ornament partly re- 
moved ; Eiver Ssjass. Purchased, 1884. 

P. 5959. Well-preserved portion of plate, 0*005 in thickness; 
Juchora, Eiver Ssjass. In addition to a general fine 
rugosity, the inner aspect exhibits a few short, small, 
irregularly disposed grooves, with raised lateral borders 
(cf. fig. of " AsteroJepis asmussi " in Pander's Placoderm. 
devon. Syst. pi. vii, fig. 32). Purchased, 1889. 

Other plates have also been assigned to Psammosteus under the 
folio whig names : — 

Psammosteus granulatus, F. M'Coy, Ann. Mag. Nat. Hist. [2] 
vol. ii. (1848), p. 7. — Lower Carboniferous ; Kesh, Co. Fer- 
managh. [Dublin Museum.] 

Psammosteus undulatus, L. Agassiz, Poiss. Foss. Y. Gr. P. (1845), 
p. 106, pi. xxxi. figs. 11, 12 : Placosteus undulatus, 
L. Agassiz, Poiss. Foss. vol. i. (1844), p. xxxiii (name 
only). — Devonian ; N.W. Russia. 

Psammosteus vermicularis, F. M'Coy, torn. cit. p. 7. — Lower Car- 
boniferous ; Fallaghloon, Maghera. [Dublin Museum.] 

The plate described as follows also exhibits some external 
resemblance to Psammosteus, but its histological structure is un- 
known : — 

Lophosteus superbus, C. H. Pander, Foss. Fische Silur. Syst. 
(1856), p. 62, pi. vi. fig. 23. — Upper Silurian ; Ohhesaar, 
Island of Oesel. 

In general external aspect the spines from the American Corni- 
ferous Limestone named Acanthaspis (J. S. Newberry, Pep. Geol. 
Surv. Ohio, vol. ii. pt. ii. 1875, p. 36) and Acantholepis (J. S. New- 
berry, ibid. p. 38) are very suggestive of the triangular ichthyodo- 
rulites assigned above to Psammosteus : their histological structure, 



ICHTHYODORULITES. 129 

however, is unknown. Some of these fossils were originally named 
Oracanthus dbbreviatus, 0. fragilis, and 0. granulatus (J . S. New- 
berry, Bull. National Institute, 1857), but only the following two 
species have been fully defined : — 

Acanthaspis armatus, J. S. Newberry, Rep. Geol. Surv. Ohio, 
vol. ii. pt. ii. (1875), p. 37, pi. lv. figs. 1-6 1 . — Corniferous 
Limestone (Lower Devonian) j Ohio. [Columbia College, 
New York.] 

Acantholepis pustidosus, J. S. Newberry, ibid. p. 38, pi. lvi. 
figs. 1-6 1 .— Ibid. [Columbia College, New York.] 



Genus STETHACANTHUS, Newberry. 

[Palaeoz. Fishes N. America (Mon. U. S. Geol. Surv. no. xvi. 
1889), p. 198.] 

Spines much laterally compressed, " broadly falcate in outline, the 
conical summit compressed, with anterior and posterior margins 
rounded"; base of insertion broad. Convex margin with long 
sulcus exposing the internal cavity ; concave margin at about one- 
third of its length from the base " rising into a strong, often tumid, 
shoulder"; sides unornamented, exhibiting the fibrous texture of 
the spine. 

This genus is not represented in the Collection, but the two 
following species are recognized : — 

Stethacanthus altonensis, J. S. Newberry, Palaeoz. Pishes N. 
America (1889), p. 198, pi. xxiv. : Physonemus altonensis, 
St. John & Worthen, Pal. Illinois, vol. vi. (1875), p. 454, 
pi. xix. figs. 1-3. — Upper St. Louis Limestone ; Illinois 
and Iowa. [Type species.] 

Stethacanthus tumidus, J. S. Newberry, op. cit. p. 198, pi. xxv. 
figs. 1, 2. — Berea Grit; Berea, Ohio. [Columbia College, 
New York.] 

In texture and general aspect the spines thus described are so 
similar to those found with Gyracanthus, that it seems not impro- 
bable they may truly belong to an Elasmobranch already known by 
its fin-spines, which have received a distinct name. 

1 Both these descriptions and figures are reprinted in J. S. Newberry, 
Palasoz. Fishes N. America (Mon. U.S. Geol. Surv. no. xvi. 1889), pp. 33-37, 
pi. xxxi. 

PAET II. K 



130 1CHTHYODOKTTLITES. 

Genus PHYSONEMUS, M'Coy. 

[Ann. Mag. Nat. Hist. [2] vol. ii. 1848, p. 117.] 

Syn. Xystracanthus, J. Leidy, Proc. Acad. Nat, Sci. Philad. 1859, p. 3. 
Drepanacanthus, Newberry & Worthen, Pal. Illinois, vol. ii. 
1866, p. 120. 

Spines much laterally compressed, strongly arched, often hook- 
shaped ; base of insertion broad. Sides of exserted portion more or 
less ornamented with tuberculated longitudinal ridges ; small den- 
ticles present upon the concave edge. 

According to Newberry and Worthen, the form of the inserted 
portion in the so-called Drepanacanthus proves that the spine was 
arched forwards. 

Physonemus arcuatus, M'Coy. 

1848. Physonemus arcuatus, F. M'Coy, Ann. Mag. Nat. Hist. [2] 

vol. ii. p. 117. 
1855. Physonemus arcuatus, F. M'Coy, Brit. Palaeoz. Foss. p. 638, 

pi. iii. i. fig. 29. 
1883. Physonemus arcuatus, J. W. Davis, Trans. Roy. Dublin Soc. [2] 

vol. i. p. 367, pi. xlvii. fig. 8. 

Type. Woodwardian Museum, Cambridge. 
The type species. 

Form. Sf Loc. Lower Carboniferous Limestone : Armagh and 
Gloucestershire. 

P. 2239. Base of spine ; Armagh. Egerton Coll. 

P. 2519. Distal portion of spine ; Armagh. This is probably the 
specimen assigned provisionally to Chalazacanthus verru- 
cosus by J. W. Davis, loc. cit. p. 371. Enniskillen Coll. 

P. 2520-21. Two more imperfect specimens, both "decorticated"; 
Armagh. Enniskillen Coll. 

38022. Similar specimen ; Black Rock, Bristol. Purchased, 1863. 

Physonemus attennatus, Davis. 

1883. Physonemus attenuatus, J. W. Davis, Trans. Roy. Dublin Soc. 
[2] vol. i. p. 369, pi. xlvii. fig. 10. 

Type. Formerly in the Enniskillen Collection 1 . 

Form. 6c Loc. Lower Carboniferous Limestone : Armagh. 

1 See Introduction. 



ICHTHYODORULITES. 131 

P. 2889. Four imperfect and much abraded specimens. 

EnnisJcillen Coll. 

P. 2870. Much abraded smaller spine, doubtfully of this species ; 
Hook Point, Wexford. Enniskillen Coll. 



Physonemus hamatus (Agassiz). 

1837. Onchus hamatus, L. Agassiz, Poiss. Foss. vol. iii. p. 9, pi. i. 
figs. 7, 8. 

1883. Physonemus hamatus, J. W. Davis, Trans. Roy. Dublin Soc. [2] 
vol. i. p. 370, pi. xlvii. figs. 9, 11. 

1884. Physonemus hamatus, J. W. Davis, Quart. Journ. Geol. Soc. 
vol. xl. p. 617, pi. xxvi. fig. 6. 

Type. Bristol Museum. 

Form. <$f Log. Lower Carboniferous Limestone : Gloucestershire. 
Upper Carboniferous Limestone : Yorkshire. 

P. 4901. Spine of the form assigned to this species by J. W. Davis, 
loc. cit. (1884) ; Yoredale Rocks, Wensleydale, Yorkshire. 

Home Coll. 

The following species have also been described, but there are no 
examples in the Collection : — 

Physonemus acinaciformis : Xystr acanthus acinaciformis, St. John 
& Worthen, Pal. Illinois, vol. vi. (1875), p. 459, pi. xx. 
fig. 2. — Coal-Measures ; Illinois. 

Physonemus anceps : Drepanacanthus anceps, Newberry & Wor- 
then, Pal. Illinois, vol. ii. (1866), p. 122, pi. xii. fig. 8: 
Xystracanthus anceps, St. John & Worthen, op. cit. vol. vi. 
p. 458. — Coal-Measures ; Illinois. [Type of Drepanacan- 
thus. ~\ 

Physonemus arcuatus: Xystracanthus arcuatus, J. Leidy, Proc. 
Acad. Nat. Sci. Philad. 1859, p. 3, and Ext. Yert. Fauna 
W. Territ. (Rep. U.S. Geol. Surv. vol. i. 1873), p. 312, 
pi. xvii. fig. 25. — Upper Coal-Measures ; Kansas. [Type 
of Xystr 'acanthus , requires new specific name.] 

Physonemus carinatus, St. John & "Worthen, op. cit. vol. vi. p. 452, 
pi. xviii. figs. 4, 5. — Kinderhook Limestone ; Illinois. 

Physonemus Chester ensis, St. John & Worthen, op. cit. vol. vi. 
p. 455, pi. xix. fig. 4. — Chester Limestone ; Illinois. 

Physonemus clepressus, St. John & Worthen, op. cit. vol. vi. p. 452, 
pi. xviii. fig. 3. — Kinderhook Limestone ; Illinois. 

Physonemus falcatus, St. John & Worthen, op. cit. vol. vii. (1883), 
p. 252, pi. xxiv. fig. 6. — St. Louis Limestone ; Missouri. 

k2 



132 ICHTHYODORfLITES. 

Physonemus gcmmatus: Drepanacanthus gcmmatus, Newberry & 

Worthen, Pal. Illinois, vol. ii. (1866), p. 123, pi. xiii. 

fig. 1. — Keokuk Limestone; Iowa. 
Physonemus giganteus: Xystracanthus giganteus, W. Waagen, 

Salt-Range Fossils (Palaeonfc. Indica, ser. 13), vol. i. 

(18S0), p. 76, pi. vii. fig. 2. — Productus-Limestone ; 

Salt Range, Punjab, India. 
Physonemus gig as, Newberry & Worthen, op. cit. vol. iv. (1870), 

p. 373, pi. ii. fig. 1. — Burlington Limestone, Illinois. 
Physonemus JconincJci: Xystracanthus honinclci, M. Lohest, Ann. 

Soc. Geol. Belg. vol.xi. (1883), p. 322, pi. v. figs. 2, 3.— 

Lower Carboniferous (Ampelite) ; Belgium. 
Physonemus mirabilis: Xystracanthus miralih's, St. John & Wor- 
then, Pal. Illinois, toI. vi. p. 458, pi. xx. fig. 1. — Coal- 

Measures; Illinois. 
Physonemus parvulus, St. John & Worthen, op. cit. vol. vi. p. 453, 

pi. xviii. figs. 11, 12. — Keokuk Limestone ; Missouri and 

Illinois. 
Physonemus proclivus, St. John & Worthen, op. cit. vol. vi. p. 451, 

pi. xviii. figs. 1, 2. — Kinderhook Limestone; Illinois. 
Physonemus reversus : Drepanacanthus reversus, St. John & Wor- 
then, op. cit. vol. vi. p. 456, pi. xix. figs. 5, 6, and vol. vii. 

p. 253, pi. xxiv. fig. 5. — Upper St. Louis Limestone ; 

Illinois and Missouri. 
Physonemus stellatus, J. S. Newberry, Palaeoz. Fishes N. America 

(Mon. U.S. Geol. Surv. no. xvi. 1889), p. 200, pi. xxi. 

fig. 12. — St. Louis Limestone ; Greencastle, Indiana. 

[Columbia College, New York.] 

Two fragments of spines, doubtfully of this genus, from the Pro- 
ductus-Limestone of the Salt Range, Punjab, are named Xystra- 
canthus gracilis, W. Waagen (torn. cit. 1879, p. 19, pi. i. figs. 2, 5), 
and X. major, W. Waagen (ibid. p. 19, pi. ii. fig. 9). 

The so-called Physonemus subteres, from the Lower Carboniferous 
Limestone of Armagh, named by Agassiz (Poiss. Foss. vol. iii. 1843, 
p. 176), and described by F. M'Coy (Brit, Palaaoz. Foss. 1855, 
p. 638, pi. iii. i. fig. 30) and J. W. Davis (Trans. Roy. Dublin Soc. 
[2] vol. i. 1883, p. 368, pi. xlvii. fig. 12), does not appear to belong 
to this genus ; and a very doubtful fossil from the Carboniferous 
Limestone of Moscow is named Drepanacanthus pectmifer, U. Traut- 
schold, Nouv. Mem. Soc. Imp. Nat. Moscou, vol. xiii. (1874), p. 297, 
pi. xxviii. fig. 10. 

The fragments of spines, from the Lower Carboniferous of the 
United States, named Batacanthus, St. John & Worthen (op. cit. 



ICRTHYODORULITES. 133 

vol. vi. p. 468), are perhaps of the same type as Physonemus. Two 
species are recognized : — B. baculiformis, St. John & Worthen 
(ibid. p. 469, pi. xxi. figs. 4-8), from the Keokuk Limestone of Mis- 
souri, Iowa, and probably Illinois ; and B. stellatus, St. John & 
Worthen (ibid. p. 470, pi. xxi. figs. 1-3), previously named Drepa- 
nacanthus? stellatus, Newberry & Worthen (Pal. Illinois, vol. ii. 
1866, p. 125, pi. xii. fig. 7), from the Keokuk Limestone of Illinois. 
A third spine is also doubtfully placed here, namely, B. ? necis, St. 
John & Worthen (op. cit. vol. vii. p. 253, pi. xxv. fig. 4), from the 
Keokuk Limestone of Iowa ; and it is suggested (op. cit. vol. vi. 
p. 468) that the so-called Myriacanihus semigranulatus, H. Roman- 
owsky (Bull. Soc. Imp. Nat. Moscou, 1864, pt. ii. p. 167, pi. iv. 
fig. 34), may be of the same generic type. 



Genus STICHACANTHUS, Koninck. 
[Faune Calc. Carb. Belg. pt. i. 1878, p. 70.] 

Spines much laterally compressed, straight or slightly arched, 
broad and triangular, or narrow and elongated ; sides of exserted 
portion ornamented with longitudinal series of rounded tubercles 
placed upon low ridges, except towards the base, where the ridges 
disappear. 

Stichacanthus coemansi, Koninck. 

1878. Stichacanthus coemansi, L. G. de Koninck, Faune Calc. Carb. 
Belg. pt. i. p. 71, pi. vii. figs. 4, 5. 

Type. Boyal Museum of Natural History, Brussels. 
The type species. 

Form. 6f Loo. Lower Carboniferous Limestone : Belgium, Shrop- 
shire, and Gloucestershire. 

38197. Portion of spine noticed by de Koninck, op. cit. p. 71 ; 
Oreton, Shropshire. Purchased, 1861. 

P. 229-30.' A much-abraded specimen, and an imperfect spine, with 
finer ornament, doubtfully of this species ; Oreton. 

Weaver-Jones Coll. 

42240. Terminal portion of spine similar to No. P. 230 ; Oueton. 

Baugh ColL 



134 ICHTHYODORULITES. 

Stichacanthus tortworthensis, Davis. 

1883. Stichaca}it/ms torticorthensis. J. W. Davis, Trans. Roy. Dublin 
Soc. [2] vol. i. p. 532, pi. lxv. fig. 2. 

Type. Earl of Ducie, Tortworth Court. 

Form. $• Loc. Carboniferous Limestone : Gloucestershire and 
Shropshire. 

42234. Portions of a spine of similar proportions to the type speci- 

men ; Oreton, Shropshire. The concavely-arehed margin 
is rounded, the opposite truncated by a flat area, which 
becomes channelled distally. Upon one edge of the flat- 
tened area there is a series of relatively large denticles ; 
and on the sides near the base the longitudinal ridges 
connecting the tubercles disappear. Baugh Coll. 

42234 a. Basal portion of a similar broad spine ; Oreton. 

Baugh Coll. 

42236. A much more slender spine of a similar type ; Oreton. 

Baugh Coll. 

The following specimens only differ from the typical Stichacanthus 
in the fact that the superficial tubercles are not connected even by 
faint ridges : — 

42235. An imperfect small broad spine ; Oreton. Baugh Coll. 

14195. Portion of a small spine, perhaps narrower ; Oreton. 

Purchased, 1868. 

42245. Proximal portion of a small spine showing a large base of 
insertion; Oreton. Baugh Coll. 

The following species is also doubtfully placed here : — 

Stichacanthus (?) humilis, L. G. de Koninck, Paune Calc. Carb. 
Belg. pt. i. (1878), p. 72, pi. vii. fig. 6. — Lower Carboni- 
ferous Limestone ; Soignies, Belgium. [Eoyal Museum Nat. 
Hist., Brussels.] 



ICHTHYODORULITES. 



135 



Genus ORACANTHUS, Agassiz. 
[Poiss. Foss. vol. iii. 1837, p. 18.] 
Syn. Platyacanthus, F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. ii. 1848, 
p. 120. 
Pnigeacanthus, St. John & Worthen, Pal. Illinois, vol. vi. 1875, 

p. 480. 
Phoder acanthus, J. W. Davis, Trans. Roy. Dublin Soc. [2] vol. i. 
1883, p. 533. 

Spines attaining to a very large size, much laterally-compressed, 
usually unsymmetrical, broad and triangular, rarely elongated and 
slightly arched ; internal cavity very large, base of insertion shorb 
or absent. Sides of exserted portion ornamented by large tubercles, 
with a tendency to arrangement in transverse series, sometimes 
fused. 

As observed by J. W. Davis 1 , the broad triangular spines of this 
genus are unsymmetrical and must have been arranged in pairs ; 
the lower margin of one side of each spine being straight, while the 
internal cavity on the other side is exposed by a great excavation. 
Such spines have subsequently been discovered by E. H. Traquair 2 , 
forming a pair of backwardly-directed weapons behind the head of 
an Elasmobranch ; and microscopical sections have proved the 
absence of bone-corpuscles in their structure. The spines were 
originally supposed by Agassiz 3 to be referable to Oroclus ; argu- 
ments in favour of their pertaining to Psammodus were afterwards 
discussed by R. Etheridge, Jim. 4 ; and more recently they have been 
regarded by InostranzefT 5 as not improbably the spines of Poly- 
rhizodus. 

The narrow elongated spines seem to be homologous with the 
typical spines named Gyracanihus, while the broader examples cor- 
respond to the thin, hollow, triangular bodies also met with in the 
last-named genus. 

Oracanthus milleri, Agassiz, 

[Plate I. fig. 3.] 

1837. Oracanthus milleri, L. Agassiz, Poiss. Foss. voL iii. p. 13, pi. iii. 
figs. 1-4. 



1 Trans. Eoy. Dublin Soc. [2] vol. i. p. 530, pi. lxiv. fig. 1. 

2 Geol. Mag. [3] vol. v. (1888), p. 86. 

3 Poiss. Foss. vol. iii. p. 171. 

* Geol. Mag. [2] vol. iv. (1877), p. 308. 

5 Trudui St. Peterb. Obshch. Estest-Ispuit. vol. xix. (1888), p 16. 



136 ICHTHYODORULITES. 

1887. Oracanthus minor, L. Agassiz, ibid. p. 16, pi. iii. figs. 5, 6. 

[Bristol Museum.] 
1843. Oracanthus confluens, L. Agassiz, ibid. p. 177 (name only). 
1855. Oracanthus milleri, F. M'Coy, Brit. Palseoz. Foss. p. 634. 

1877. Oracanthus milleri, R. Etheridge, Jun., Geol. Mag. [2] vol. iv. 
p. 307, pi. xiii. figs. 4-6. 

1878. Oracanthus milleri, L. G. de Koninck, Faune Oalc. Carb. Belg. 
p. 69, pi. v. fig. 10. 

1883. Oracanthus milleri, J. W. Davis, Trans. Roy. Dublin Soc. [2] 
vol. i. p. 525, pi. lxiii. figs. 1-4, pi. lxiv., pi. lxv. figs. 3, 4 (? also 
pi. lxii.). 

Type. Bristol Museum. 

The type species. 

Form. Sf Loc. Lower Carboniferous Limestone : Gloucestershire, 
Lanarkshire, and Armagh. Upper Carboniferous Limestone : Vise, 
Belgium. 

28857. Imperfect spine, originally measuring 0*3 in length, and 
0*125 across the base ; Bristol. Purchased, 1854. 

22665. Imperfect similar spine, with an attenuated smooth terminal 
portion, and two fragments ; Bristol. Purchased, 1848. 

P. 2241. Portion of similar spine free from matrix; Bristol. 

Egerton Coll. 

P. 3125-6, P. 3130. Imperfect large spine, and two fragments; 
Bristol. Enniskillen Coll. 

P. 3128. Smaller specimen, with one narrow face broken away, 
and the boundary of the base much obscured on one side ; 
figured by J. W. Davis, loc. cit. pi. lxiv. fig. 1 ; Bristol. 

EnnisTcillen Coll. 

34983. Portion of a very small spine ; Bristol. Purchased, 1860. 

P. 2873-5. Small broad spines figured by J. W. Davis, loc. cit. 
pi. lxiii. figs. 1-3 ; Armagh. Enniskillen Coll. 

P. 3131. More imperfect similar spine; .Armagh. Enniskillen Coll. 

P. 3129. Imperfect more elongated spine ; Armagh. 

EnnisTcillen Coll. 

P. 3132-3. Five terminal extremities of spines, and three fragments ; 
Armagh. Enniskillen Coll. 

P. 3135. Long slender dermal plate, with spatulate extremity, de- 
scribed and figured by J. W. Davis, loc. cit. p. 529, pi. lxv. 
fig. 3 ; Armagh. Enniskillen Coll. 



ICH.THYODORULITES. 137 

P. 3136-7. Two more imperfect examples of the same, one figured 
loc. cit. pi. lxv. fig. 4 ; Armagh. Enniskillen Coll. 

P. 2887. Smaller portion probably of a similar plate, figured loc. 
cit. pi. lxii. fig. 13 ; Armagh. Enniskillen Coll. 

The following spines may also pertain to this species, but differ 
from the foregoing in their slenderness, and in the fusion of the 
superficial tubercles into oblique transverse ridges : — 

P. 2238. Fragment of a small spine, narrow and straight ; Armagh. 

Egerton Coll. 

P. 3134, P. 3134 a. Larger portion of a similar spine, free from 
matrix ; also a fragment ; Armagh. The spine (PI. I. 
fig. 3) is much compressed, with the convex edge acute, 
and worn at the distal end; the opposite edge being 
straight and flat, or longitudinally channelled. So far as 
preserved, the specimen seems to be bilaterally symme- 
trical ; and the oblique lateral ridges are inclined in an 
exactly opposite direction to those of Gyracanthus. 

Enniskillen Coll. 

P. 3127. Remains of a larger more arched spine ; Castle Espie, Co. 
Down, Ireland. Enniskillen Coll. 

The numerous small dermal plates mentioned below are also 
provisionally associated with Oracanthus milleri by J. W. Davis, loc. 
cit. They are thin, consist of vascular dentine, and are externally 
ornamented with rounded ganoine-tubercles, irregularly disposed. 
Their nearest known analogues are perhaps to be found in the 
dermal plates of the Liassic Chimaeroid, Myriacantlius (p. 43). 
Similar plates have already been described by E. H'Coy under the 
names of Coccosteus ? carbonarius \ Asterolepis verrucosa 2 , and Pla- 
ty acanthus isosceles 3 ; and the triangular forms are named Pnigea- 
canthus by St. John & Worthen, loc. cit. 

All these specimens were obtained from the Lower Carboniferous 
Limestone of Armagh, and are from the Enniskillen Collection. 

P. 2876-7. Elongated symmetrical plate, bifurcated at one ex- 
tremity, and portion of a similar plate, figured, loc. cit. 
pi. lxii. figs. 1, 2 (" central dorsal bone of cranium "). 

1 Ann. Mag. Nat. Hist. [2] vol. ii. (1848), p. 9. [Geol. Soc. London.] 

2 Ibid. p. 9. [Geol. Soc. London.] 

3 Ibid. p. 120. [Geol. Soc. London.] 



133 ICHTHY0D0RULITE3. 

P. 2878. Elongated bilaterally-symmetrical plate pointed at one 
extremity, figured, loc. cit. pi. lxii. fig. 3 ("jugular plate ? 
or sphenoid bone "). 

P. 2886. Much- broken plate, figured, loc. cit. pi. lxii. fig. 12 (" jugular 
plate ? "). 

P. 2881. Unsymmetrical plate, figured, loc. cit. pi. lxii. fig. 6 ("cheek- 
plate or operculum "). 

P. 2879. Nearly similar smaller plate, figured, loc. cit. pi. lxii. fig. 4 
(" upper jaw ? "). 

P. 2882. Elongated unsymmetrical pointed plate, figured, loc. cit. 
pi. lxii. fig. 7 (" lower jaw "). 

P. 2880, P. 2883-5. Irregularly shaped plates, figured, loc. cit. 
pi. lxii. figs. 5, 8, 10, 11 ("head-bones"). 

P. 2888, P. 2901. Imperfect small dermal plates or spines, mostly 
triangular. 

Oracanthus pustuloses, Agassiz. 

3837. Oracanthus pustulosus, L. Agassiz, Poiss. Foss. vol. iii. p. 15, 

pi. ii. figs. 3, 4. 
1883. Phoder 'acanthus grandis, J. W. Davis, Trans. Roy. Dublin Soc. 

[2] vol. i. p. 534, pi. lxv. fig. 1. [British Museum.] 

Type. Bristol Museum. 

Form. 6f Loc, Lower Carboniferous Limestone : Bristol, Glouces- 
tershire. 

P. 4716. Type specimen of Phoderacanthus grandis, Davis, described 
and figured, loc. cit. Presented by the Earl of Ducie, 1884. 



Oracanthus pnigeus, Newberry & Worthen. 

1866. Oracanthus pnigeus, Newberry & Worthen, Pal. Illinois, vol. ii. 

p. 117, pi. xii. fig. 3. 
1875. Pnigeacanthus deltoides, St. John & "Worthen, Pal. Illinois, 

vol. vi. p. 480. 
1883. Pnigeacanthus pnigeus, St. John & Worthen, op. cit. vol. vii. 

p. 260. 

Form, fy Loc. Lower Carboniferous (Keokuk Limestone) : Iowa 
and Illinois, U.S.A. 

P. 2900. Imperfect specimen, probably of this species; "Warsaw, 
Illinois. Ennishillen Coll. 



ICHTHTODORULITES. 



139 



The following species of Oracanthus have also been described, 
but, in some cases, the distinctive features are very slight, and if 
such were regarded as of specific value in Britain, 0. milleri would 
be considerably subdivided : — 

Oracanthus armigerus, E,. H. Traquair, Trans. Edinb. Geol. Soc. 
vol. v. (1887), p. 313 (name only), and Geol. Mag. [3] 
vol. v. (1888), p. 86. — Calciferous Sandstones; Abden, 
Fife, and Eskdale, Dumfries. Carboniferous Limestone ; 
Ayrshire. [Collection of R. Craig, Esq., and also portion 
of fish in Edinburgh Museum.] 

Oracanthus? obliquus, St. John & Worthen, Pal. Illinois, vol. vi. 
(1875), p. 477, pi. xxii. fig. 16.— Upper Keokuk Lime- 
stone ; Illinois. 

Oracanthus rectus, St. John & Worthen, op. cit. vol. vii. (1883), 
p. 257, pi. xxv. fig. 3. — Chester Limestone ; Illinois. 

Oracanthus trigonalis ; Pnigeacanthus trigonalis, St. John & 
Worthen, op. cit. vol. vii. p. 259, pi. xxiv. fig. 4. — St. 
Louis Limestone ; Illinois. 

Oracanthus vetustus, J. Leidy, Proc. Acad. Nat. Sci. Philad. vol. vii. 
1856, p. 414, and Journ. Acad. Nat. Sci. Philad. [2] 
vol. iii. (1856), p. 161, pi. xvi. figs. 1-3 ; St. John & 
"Worthen, op. cit. vol. vii. p. 255, pi. xxiv. fig. 2 : Ora- 
canthus consimilis, St. John & Worthen, op. cit. vol. vi. 
p. 478, pi. xxii. fig. 15. — Upper St. Louis Limestone; 
Illinois, Missouri, and Iowa. [Academy of Natural Sci- 
ences, Philadelphia.] 

Closely related to Oracanthus is the very large spine described as 
follows: — 

Antacanthus insignis, G. Dewalque, Ann. Soc. Geol. Belg. vol. v. 
(1877), p. lx; L. G. de Koninck, Paune Calc. Carb. Belg. 
pt. i. pp. 72, 73, pi. viii. figs. 1-3. — Lower Carboniferous 
Limestone ; Liege. [University of Liege.] 



Genus GYRACANTHUS, 

[Poiss. Eoss. vol. iii. 1837, p. 17.] 

Syn. Mitrodus, R Owen, Trans. Odontol. Soc. vol. v. 1867, p. 338. 

Spines of two distinct types, the one evidently connected with 
fins, the other free. Fin-spines elongated, robust, more or less 
arched, irregularly rounded or oval in transverse section, except 
towards the unworn apex, which is compressed ; base of insertion 
large, with the internal cavity open for a considerable extent pos- 



140 ICHTHTODOR ELITES. 

teriorly. The longitudinal mesial line of the anterior face, except 
near the unworn apex, denned only by the superficial ornament, 
which consists of parallel, oblique, transverse ridges, diverging in 
pairs from this line and inclined towards the inserted extremity ; 
posterior face with a narrow unornamented area, sometimes bounded 
by a series of denticles on one side ; unworn apex also destitute of 
ornament. Free spines broad, laterally compressed, usually triangular, 
sometimes of reniform shape ; base-line straight on one side, much 
excavated on the other, the central cavity very large and its walls 
thin ; exserted portion having a rough fibrous appearance, usually 
with a few rounded tubercles at the distal pointed end, these some- 
times exhibiting a tendency to arrangement in transverse series. 

The paired spines have been described in detail by E. H. Traquair \ 
who points out that no known British specimens are bilaterally 
symmetrical. Notwithstanding this peculiarity, Agassiz supposed 
that they might have armed the dorsal fins ; and Kirkby and 
Atthey 2 seem to have been the first to suggest their pertaining to 
paired fins. Hancock and Atthey, in 1868 3 , considered that a few of 
the spines exhibited true bilateral symmetry, and might thus be 
median dorsal ; but Traquair regards these as the paired spines of 
young individuals, those of more mature individuals being much 
altered in appearance by the continual abrasion of the apex. 

The free spines are usually found in intimate association with 
the fin-spines, and they were thus originally described by Hancock 
and Atthey 4 as " carpal bones " (i. e. basal cartilages of the pectoral 
fins) ; an examination of microscopical sections, however, has 
demonstrated their truly dermal nature 5 . 

Pectinated shagreen-granules are also met with in association 
with the spines of Gyracanthus, and microscopical sections of these 
have been described under the name of Mitrodus quadricornis, 
Owen 6 . 

Gyracanthus formosus, Agassiz. 

1825-26. " Fish spine ?," J. de C. Sowerby, Zool. Journ. vol. i. p. 252, 

pi. viii. fig. 9, and ibid. vol. ii. p. 22. 
1837. Gyracanthus fm-mosus, L. Agassiz, Poiss. Foss. vol. iii. p. 17, 

pi. v. figs. 2-6. 

1 Ann. Mag. Nat. Hist. [5] vol. xiii. (1884), p. 38. 

2 According to Hancock and Atthey, 1868. 

3 Ann. Mag. Nat. Hist. [4] vol. i. (1868), p. 368. 

< Ann. Mag. Nat. Hist, [4] vol. i. (1868), p. 369, and ibid. vol. ix. (1872), 
p. 260. 

5 R, H. Traquair, Ann. Mag. Nat. Hiat. [5] vol. xiii. (1884), p. 44. 

6 R. Owen, Trans. Odontol. Soc. vol. v. (1867), p. 338, pi. iii. 



ICHTHY0D0KUL1TES. 141 

1837. Gyracanthus tuberculatus, L. Agassiz, ibid. p. 19, pi. i.a. figs. 1-7. 
1841. Gyracanthus formosus, E. W. Binney, Trans. Manchester Geol. 

Soc. vol. i. p. 168. 
1848. Gyracanthus sp., R. Howse, Trans. Tyneside Nat. Field Club, 

vol. i. p. 237 (assigned to G. formosus by W. King, Permian 

Fossils, 1850, p. 221). 

1867. Mitrodus quadricornis, R. Owen, Trans. Odontol. Soc. vol. v. 
p. 338, pi. iii. [Micro, section of dermal tubercle; British 
Museum.] 

1868. Gyracanthus tuberculatus, Hancock & Atthey, Ann. Mag. Nat. 
Hist. [4] vol. i. p. 368. 

1872. Gyracanthus tuberculatus, Hancock & Atthey, ibid. vol. ix. p. 260. 
1870-72. Gyracanthus tuberculatus, Hancock & Atthey, Nat. Hist. 

Trans. Northumb. and Durham, vol. iii. p. 108, and vol. iv. p. 421. 

1873. Gyracanthus, T. P. Barkas, Coal Meas. Palseont. p. 15, figs. 1-5. 
1875. Gyracanthus formosus, J. Ward, [Proc] N. Staffs. Nat. Field 

Club, p. 216, fig. 3. 

1875. Gyracanthus tuberculatus, J. Ward, ibid. p. 217. 

1876. Gyracanthus tuberculatus, J. W. Davis, Quart. Journ. Geol. Soc. 
vol. xxxii. p. 334. 

1883. Gyracanthus tuber cidatus, T. Stock, Ann. Mag. Nat. Hist. [5] 
vol. xii. p. 185, pi. vii. fig. 17 (dermal tubercle). 

1884. Gyracanthus formosus, R. H. Traquair, Ann. Mag. Nat. Hist. 
[5] vol. xiii. p. 46. 

1890. Gyracanthus tuberculatus, J. Ward, Trans. N. Staffs. Inst. 
Mining Engineers, vol. x. p. 150 ; pi. iii. fig. 1. 

Type. Unknown. 
The type species. 

Form. Sf Loo. Coal-Measures ! : English and Scottish Coal-fields, 
and Kilkenny and Queen's Co., Ireland. 

Unless stated, the precise horizon of the following specimens is 
unrecorded : — 

P. 5240. Portion of large spine; Dudley, South Staffordshire. 

Purchased, 1886. 

P. 5242. Yery small spine ; Knowles Shale, Fenton Park, North 
Staffordshire. Purchased, 1886. 

P. 1184. Abraded fragment ; Cannel Coal (Middle Coal-Measures), 
Tingley, Yorkshire. 

Presented by the Earl of Enniskillen, 1882. 

1 The impression of the base of a fin-spine in the Newcastle Museum, re- 
corded by Howse (1848) as obtained from the Lower Permian of Westoe, is 
now regarded by that author as truly an Upper Carboniferous fossil. 



142 1CHTHT0D0RULITES. 

P. 2235. Imperfect spine of moderate size, showing part of a 
posterior series of small denticles ; Lower Coal-Measures, 
Lowmoor, Yorkshire. Egerton Coll. 

P. 4179. Fragment; Lowmoor. EnnisJc Men Coll. 

P. 6234. Fragment labelled by Agassiz ; Leeds. Egerton Coll. 

P. 4178. Much broken spine ; Ruabon, Denbighshire. 

EnnisJcillen Coll. 

Fig. 10. 




Fin-spine of Gyracanthus formosus, Ag. Coal-Measures ; Dalkeith. 

36174. Abraded spine of moderate size ; Dalkeith, near Edinburgh. 

Purchased^ 1861. 

P. 2219. Two spines of medium size, and three large specimens; 
Dalkeith. Egerton Coll. 

P. 3148. Two similar spines ; Dalkeith. EnnisJcillen Coll. 

P. 2234. Nearly complete spine 0*405 in length ; Dalkeith. 

Egerton Coll. 

P. 3142 a. Base of a very large spine, and an imperfect spine of 
moderate size, said to have been found associated ; Car- 
luke, Lanarkshire. EnnisJcillen Coll. 

P. 3141, P. 3147. Spine 0*355 in length, and one of moderate size; 
Carluke. Enniskillen Coll. 

P. 2290. Fragment of spine ; Govan, near Glasgow. 

„ Presented by George Griffiths, Esq., 1882. 

P. 4180. Imperfect basal portion of large spine, probably of this 
species ; Castlecomer, Kilkenny, Ireland. Enniskillen Coll. 

41635. Two slabs of shale with dermal tubercles, probably of this 
species ; Low Main Seam, Newsham, near Newcastle-on- 
Tyne. Presented by T. P. BarJcas, Esq., 1869. 

P. 6239. Microscopical section of dermal tubercle, probably of this 
species, the type specimen of Mitrodus quadricornis, 
Owen; Newsham. 

Presented by Sir Richard Owen, K.C.B., 1890. 



ICHTHTODOEULITES. 143 

The following specimens exhibit a more tuberculated ornament 
than those enumerated above, and are thus typical examples of the 
variety tuberculatus : — 

P. 243. Very small imperfect spine ; Longton, Staffordshire. 

Weaver-Jones Coll. 

P. 5529. Small spine ; probably from the Black-shale Coal, Tibshelf 
Colliery, near Alfreton, Derbyshire. 

Presented by Edward Wilson, Esq., 1888. 

P. 3143-4. Eight and left spines of large size, much worn at the 
apex ; Low Main Seam, JNewsham, near ISFewcastle-on- 
Tyne. Ennishillen Coll. 

P. 4176-7. A still larger specimen, 0'16 in circumference at the 
base ; also an imperfectly preserved smaller spine ; News- 
ham. Ennishillen Coll. 

36149. Spine 0*335 in length, with worn apex ; Airdrie, Lanark- 
shire. Presented by Mr. Hair, 1857. 

21975 a. A comparatively slender spine, and a much worn larger 
spine ; Carluke, Lanarkshire. Purchased, 1848. 

21975. Two small spines ; Carluke. Purchased, 1848. 

P. 3139-40, P. 3142, P. 3145. Five large spines ; Dalkeith. 

Ennishillen Coll. 

P. 6235. Fragment of spine ; Dalkeith. 

P. 4181. Basal portion of spine; Queen's Co., Ireland. 

Ennishillen Coll. 

The following examples of the broad triangular dermal spines of 
Gyracanihus formosus are also contained in the Collection • — 

P. 2264. Small specimen measuring about 0*14 in height and 0-09 
across the base • Knowles Shale, Fenton, K. Staffordshire. 

Egerton Coll. 

P. 3149. Larger specimen ; Longton, N*. Staffordshire. 

Ennishillen Coll. 

P. 3150. Three specimens, apparently exhibiting a few tubercles, 
either in the form of a superficial ornament, or originally 
imbedded in an investing integument ; Low Main Seam, 
Newsham, near jSTewcastle-on-Tyne. Ennishillen Coll. 



144 ICHTHTODORULITES. 

It still remains uncertain whether the small spine from the 
Middle Coal-Measures of Tingley, Yorkshire, described under the 
name of G. daiticitlatus, Davis l , is not the unworn spine of the 
young of G. fonnosus, as described by 11. H. Traquair 2 . The 
following specimen is of the same form, but only one posterior 
series of denticles is displayed : — 

P. 2289. Nearly complete spine Olo in length, unornamented for 
a distance of 0*045 from the apex ; Coal-Measures, Govan, 
near Glasgow. Presented by George Griffiths, Esq., 1882. 

The small spine from the Calciferons Sandstone Series of Burdie- 
house, near Edinburgh, figured by S. Hibberfc, Trans. Roy. Soc. 
Edinb. vol. xiii. (1835), pi. xi. fig. 1, and assigned to Gyracanthus 
fonnosus by Agassiz (torn. cit. p. 17), is of doubtful species. The 
following are of a similar type : — 

P. 6236. Basal fragment of a large spine ; Burdiehouse. 

Purchased, ]847. 

P. 2243. Broken small spine ; Burdiehouse. Egerton Coll. 

P. 3146. Less imperfect small spine ; Burdiehouse. 

Enniskillen Coll. 

The following species have also been described, but there are no 
examples in the Collection : — 

Gyracanthus alleni, J. S. Newberry, Rep. Geol. Surv. Ohio, vol. i. 

pt. ii. (1873), p. 331, pi. xxxvii. fig. 3. — Waverly Group 

(Cuyahoga Shale) ; Ohio. [Columbia College, New York.] 
Gyracanthus compressus, J. S. Newberry, ibid. p. 330, pi. xxxvii. 

figs. 1, 2. — Waverly Group; Ohio and (?) Indiana. 

[Columbia College, New York.] 
Gyracanthus duplicatus, J. "W. Dawson, Acadian Geol. 2nd edit. 

(1868), p. 210, woodc. fig. 55 ; J. S. Newberry, Palseoz. 

Fishes N. America (Mon. U. S. Geol. Surv. no. xvi. 1889), 

p. 124. — Coal-Measures ; Nova Scotia. [Redpath Museum, 

Montreal.] 
Gyracanthus incurvus, R. H. Traquair, Geol. Mag. [3] vol. vii. 

(1890), p. 21. — Lower Devonian; Campbellton, P. Q., 

Canada. [Edinburgh Museum.] 

1 J. W. Davis, Ann. Mag. Nat. Hist. [5] vol. vi. (1880), p. 373, woodcut. 

2 Ann. Mag. Nat. Hist. [5] vol. xiii. (1884), p. 40 



ICHTHYODORTJLlTES. 1 45 

Gyracanthus inornatus, J. S. Newberry, Palaeoz. Fishes K America 
(Mon. U. S. Geol. Surv. no. xvi. 1889), p. 177, pi. xxiii. 
fig. 5. — Waverly Group ; Wayne Co., Ohio. [Columbia 
College, New York.] 

Gyracanthus magnificus, J. W. Dawson, op. cit. 2nd edit. p. 210 ; 
J". S. Newberry, Bep. Geol. Surv. Ohio, vol. ii. pt. ii. 
(1875), p. 57. — Lower Carboniferous Limestone ; Cape 
Breton. [Halifax Museum, Nova Scotia. J 

Gyracanthus nobilis, E. H. Traquair, Geol. Mag. [2] vol. x. (1883), 
p. 542, and Ann. Mag. Nat, Hist. [5] vol. xiii. (1884), 
p. 44 : G. tubercidatus, B. H. Traquair (non Agassiz), 
Geol. Mag. [2] vol. viii. (1881), p. 34.— Middle Carboni- 
ferous Limestone ; Edinburgh and Fifeshire. [Collection 
of Dr. 11. H. Traquair.] 

Gyracanthus obliquus, F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. ii. 
(1848), p. 117, and Brit, Pakeoz. Foss. (1855), p. 629, 
pi. iii. e. figs. 13, 14. — Lower Carboniferous ; Moyheeland, 
near Draperstown, Ireland. [Woodwardian Museum, 
Cambridge.] 

Gyracanthus sherwoodi, J. S. Newberry, Palaeoz. Fishes N. America 
(Mon. U.S. Geol. Surv. no. xvi. 1889), p. 119, pi. xviii. 
fig. 4. — Catskill Group ; Pennsylvania. [Columbia College, 
New York.] 

Gyracanthus youngi, B. H. Traquair, Geol. Mag. [2] vol. x. 
(1883), p. 543, and Ann. Mag. Nat. Hist, [5] vol. xiii. 
(1884), p. 47. — Middle Carboniferous Limestone ; Scottish 
Coalfield. [Collection of Dr. B. H. Traquair.] 

Gyracanthus ornatus, Agassiz (Poiss. Foss. vol. iii. p. 177), from 
the Welsh Coal-Measures, is named only, and G. almuicensis, Agassiz 
(ibid. p. 19, pi. i. a. fig. 8), from the Carboniferous Limestone of 
Alnwick, Northumberland, is too imperfectly defined for recogni- 
tion. The so-called G. ? cordatus, St. John & Worthen (Pal. Illinois, 
vol. vii. 1883, p. 251, pi. xxvi. fig. 4), from the Keokuk Limestone 
of Iowa, does not belong to this genus. 

The American pectoral spines of Gyracanthus are more laterally 
compressed than any yet known in Europe. 

Genus AGANACANTHUS, Traquair. 
[Geol. Mag. [3] vol. i. 1884, p. 64.] 

Paired spines resembling the fin-spines of Gyracanthus in shape, 
but relatively shorter and stouter, and destitute of any superficial 
PARI ii. . l 



146 1CHTHY0D0RULITES. 

ornament or layer of ganoine ; an unsymmetrical double longi- 
tudinal series of denticles on the posterior aspect distally. 

This genus is not represented in the Collection, and is known 
only by the type species : — 

Aganacanthus striahdus, R. H. Traquair, he. cit. p. 64. — Middle 
Carboniferous Limestone (Blackband Ironstone) : Borough 
Lee, near Edinburgh. [Collection of Dr. R. H. Traquair.] 

Probably to this group of Ichthyodorulites may also be assigned 
the following genus and species : — 

Gomphacanthus acutus, J. W. Davis, Quart. Journ. Geol. Soc. 
vol. xl. (1884), p. 618, pi. xxvi. fig. 9.— Lower Carboni- 
ferous (Yoredale Rocks) ; Wensleydale, Yorkshire. [York 
Museum.] 

IY. Spines probably not placed in advance of fins, but most nearly 
resembling the head-spines of the male Chimaeroids and some 
Mesozoic Cestraciont Sharks (e. g. Hybodus). 



Genus ERISMACANTHUS, M'Coy. 
[Ann. Mag. Nat. Hist. [2] vol. ii. 1848, p. 118.] 

Syn. Cladacanthus, J. W. Davis (ex Agassiz, MS.), Trans. Roy. Dublin 
Soc. [2] vol. i. 1883, p. 364. 

Basal portion of spine broad, laterally compressed, not deeply 
inserted, soon bifurcating above into two slender divergent branches 
in the same vertical plane ; one branch considerably arched, keeled, 
and pointed distally, with a series of denticles upon the concave 
margin ; the other branch longer, not tapering to a point, but ter- 
minating in a cluster of elongated tubercles. An internal cavity 
extending throughout the spine. Superficial ornament of exserted 
portion consisting o£ tubercles and sulcations, the latter predomi- 
nating in the short pointed branch of the spine. 



Erismacanthus jonesi, M'Coy. 

1843. Cladacanthus paradoxus, L. Agassiz, Poiss. Foss. vol. iii. p. 176 

(name only). 
1848. Erismacanthus jonesii, F. M'Coy, Ann. Mag. Nat. Hist. [2] 

vol. ii. p. 119. 
1848. Dipriacanthus falcatus, F. M'Coy, ibid. p. 121. [Mus. Geol. 

Soc. London.] 



ICnTHYODORULITBS. 147 

1855. Erismacanthus jonesii, F. M'Coy, Brit. Palaeoz. Foss. p. 628, 
pi. iii. k. figs. 20, 27. 

1883. Cladacanthus paradoxus, J. W. Davis, Trans. Roy. Dublin Soc. 
[2] vol. i. p. 365, pi. xlvii. figs. 1-5. [Olim Enniskillen Coll. 
See Introduction.] 

1884. Cladacanthus paradoxus, J. W. Davis, Quart. Journ. Geol. Soc. 
vol. xl. p. 617, pi. xxvi. figs. 1-5. 

Type. "Woodwardian Museum, Cambridge. 
The type species. 

Form. <5f Loc. Lower Carboniferous Limestone : Armagh. Yore- 
dale Rocks : Yorkshire. 

P. 2895-6. Six broken spines, and seven examples of the branches; 
Armagh. Enniskilltn Coll. 

P. 2897. Two examples of the longer branch of the spine, displaying 
large terminal tubercles ; Armagh. Enniskillen Coll. 

Erismacanthus major (Davis). 

1883. Cladacanthus major, J. W. Davis, Trans. Roy. Dublin Soc. [2] 
vol. i. p. 366, pi. xlvii. figs. 6, 7. 

Type. Formerly in the Enniskillen Collection (see Introduction). 
Form. Sf Loc. Lower Carboniferous Limestone : Armagh. 

P. 2898-9. Five imperfect specimens of the pointed branch of the 
spine. Enniskillen Coll. 

The following specimen is supposed to have been obtained from 
the Lower Carboniferous Limestone of Bristol : — 

P. 6257. The arched portion of a spine as large as E. major. The 
keel on the convex margin is very broad, and the denticles 
on the opposite margin large, broad, and closely arranged ; 
the sides are ornamented with fine longitudinal ridges, 
with a few small tubercles near the base. 

History unknown. 

The following species has also been described : — 

Erismacanthus maccoyanus, St. John & Worthen, Pal. Illinois, 
vol. vi. (1875), p. 461, pi. xxii. figs. 1-5. — St. Louis 
Limestone ; Illinois and Missouri, U.S.A. 

There is also a single specimen in the Collection from the Lower 
Carboniferous Limestone of Armagh (P. 2896. Enniskillen Coll.), 
which may possibly be the long branch of a distinct form of spine 

l2 



148 ICHTHYODORULITES. 

of Erismaeanthui, but cannot be certainly determined. The spine 
is laterally compressed, gently arched, tapering, and ornamented 
with fine superficial tubercles. 

The imperfect Ichthyodorulites from the Lower Carboniferous of 
the United States, described under the names of Gampsacanthus, 
St. John & Worthen (Pal. Illinois, vol. vi. 1875, p. 471), and Lecra- 
canthus, St. John & Worthen (ibid. p. 475), appear to be fragments 
of ErismacantJi us-shaped spines. To the former "genus" are as- 
signed G. ? latus, St. John & Worthen (ibid. p. 474, pi. xxii. fig. 14), 
from the Keokuk Limestone of Missouri : G. squamosus, St. John & 
Worthen (ibid. p. 473, pi. xxii. fig. 13), from the Upper St. Louis 
Limestone of Missouri ; and G. typus, St. John & Worthen (ibid. 
p. 472, pi. xxii. fig. 12), from the Upper St. Louis Limestone of 
Illinois and Missouri. Lecracanthus has only a single species, L. 
unguiculus, St. John & Worthen (ibid. p. 476, pi. xxii. figs. 10, 11), 
from the Upper St. Louis Limestone of Missouri and Illinois. 

A fragment, probably of a similar nature, from the Lower Car- 
boniferous Limestone of Armagh, forms the type of Dipriacanihus, 
F. M'Coy (Ann. Mag. Nat. Hist. [2] vol. ii. 1848, p. 121), with 
the single species, D. stokesii, F. M'Coy (ibid. p. 121, and Brit. 
Palaeoz. Foss. p. 627, pi. iii. x. fig. 18), noticed later by J. W. Davis, 
Trans. Eoy. Dublin Soc. [2] vol. i. (1883), p. 360, pi. xlviii. fig. 10. 
[Woodwardian Museum, Cambridge.] 

Genus LISTRACANTKUS, Newberry & Worthen. 
[Pal. Illinois, vol. iv. 1870, p. 371.] 

Spine small, gently arched, and much laterally compressed, ex- 
panding and abruptly truncated at the base. Sides ornamented 
with numerous acute longitudinal ridges ; the concave and convex 
margins provided with many divergent, slender denticles, pointing 
towards the apex of the spine. 

The type species is L. hystrix, Newberry & Worthen (torn. cit. 
p. 372, pi. ii. fig. 3), from the Coal-Measures of Illinois and Ohio \ 
Spines from the Upper Carboniferous Limestone Series of Mons, 
Belgium, are also assigned to this species by L. G. de Koninck 
(Faune Calc. Carbf. Belg. pt. i. 1878, p. 75, pi. v. fig. 11), and the 
following specimen resembles the latter : — 

47307. Spine 0-015 in length, but wanting the apex ; Castiaux, 
near Mons, Belgium. In this specimen the alternate 

1 J. S. Jvewberry, Rep. Geol. Surv. Ohio, vol. i. pt. ii. (1873), p. 337, and 
ibid. toI. ii. pt. ii. (1875), p. 66, pi. hx. fig. 5. 



ICHTHYODORTJLITES. 149 

denticles of the concave margin appear to be directly con- 
tinuous with the lateral ribs. 

Presented by Prof. L. G. de KonincJc, 1876. 

The following species have also been described : — 

Listracanihus beyriehi, A. von Koenen, Neues Jahrb. 1879, 
p. 341, pi. vii. fig. 1 : Pamphr actus hydrqphilus, H. Hey- 

marm (errore), Sitzungsb. niederrhein. Gesell. 1870, 
p. 217. — Culm-Measures ; Herborn, Nassau. 
Listracanihus hildrethi, J. S. Newberry, Eep. Geol. Surv. Ohio, 
vol. ii. pt. ii. (1875). p. 56, pi. lix. fig. 6. — Carboniferous; 
Ohio. [Marietta College, Ohio.] 

A species of this genus from the Calciferous Sandstones of East 
Kilbride, Lanarkshire, is also preserved in the collection of Dr. 
John Hunter, Braidwood, near Carluke. 



Genus BYSSACANTHUS, Agassiz. 
[Poiss. Foss. Vieux Gres Rouge, 1845, pp. Ill, 116.] 

Basal portion of spine broad, not deeply inserted, with a large 
central eavit} T , tapering above and passing into a cylindrical elon- 
gated portion, straight or slightly arched, with a blunt apex. The 
surface of the cylindrical portion ornamented with coarse longitu- 
dinal ridges, diverging and fewer upon the broad basal portion. 

Byssacanthus crenulatus, Agassiz. 

1845. Byssacanthus crenulatus, L. Agassiz, op. cit. pp. Ill, 116, 

pi. xxxiii. figs. 11-14. 
1860. Byssacanthus crenulatus, E. von Eichwald, Leth. Rossica, vol. i. 

p. 1598. 

Type. Keyserling Collection. 

The type species. 

Form, fy Loc. Devonian : St. Petersburg, Russia. 

P. 2251. Two fragments. Egerton Coll. 

The following species have also been described, but there are no 
examples in the Collection : — 

Byssacanthus arcuatus, L. Agassiz, Poiss. Foss. V. G. R. (1845), 
p. Ill : Onchus arcuatus, L. Agassiz, Poiss. Foss. vol. iii. 



150 1CHTI1YODORULITE3. 

(1S37), p. 7, pi. i. figs. 3-5. — Old Red Sandstone ; Brom- 
yard, Herefordshire. [? Cephalaspidian cornua.] 

Byssacanthus gosseleti, C. Barrois, Ann. Soc. Geol. du Nord, vol. ii. 
(1875), p. 200, and Comptes Rendus Assoc. Franc,. 1874, 
p. 381.— Upper Devonian ; Couvin, Ardennes. 

Byssacantlms Icevis, L. Agassiz, Poiss. Foss. V. G. R. (1845), 
pp. Ill, 117, pi. xxxiii. fig. 15: Byssacanthus dilatatus, 
E. von Eichwald, Leth. Rossica, vol. i. (1860), p. 1598 : 
Byssacantlms (Onchus) dilatatus, E. von Eichwald, Bull. 
Soc. Imp. Nat. Moscou, vol. xix. (1846), p. 288, pi. x. 
figs. 2, 3. — Devonian ; St. Petersburg. 

A spine from the Upper Silurian of the Baltic Provinces, ex- 
hibiting considerable resemblance to Byssacanthus, is named Rabda- 
canthus truncatus, 0. H. Pander, Foss. Fische Silur. Syst. russ.- 
balt. Gouvernements (1856), p. 69, pi. vi. fig. 26. 

The following genera also seem to belong to this group of Ich- 
thyodorulites : — 

Cyrtacanthus, J. S. Newberry (Rep. Geol. Surv. Ohio, vol. i. pt. ii. 
1873, p. 306), with the single species, C. dentatus, Newberry, ibid. 
p. 307, pi. xxix. fig. 5. [Doubtfully assigned to Erismacanihus 
(" Cladacanthus ") by J. S. Newberry, Palaeoz. Fishes N. America 
(Mon. U.S. Geol. Surv. no. xvi. 1889), p. 29.]— Corniferous Lime- 
stone (Lower Devonian); Delaware, Ohio. [Columbia College, 
New York.] 

Euacanthus, H. Trautschold (Bull. Soc. Imp. Nat. Moscou, 1883, 
pt. ii. p. 171), with the single species, E. margaritatus, Traut- 
schold, ibid. p. 172, pi. v. figs. 7-13. — Carboniferous Limestone ; 
Moscow. [Trautschold Collection, Breslau.] 

Harpacanthus, R. H. Traquair (Ann. Mag. Nat. Hist. [5] 
vol. xviii. 1886, p. 493), with the single species, H. fimbriatus, 
Traquair (ibid. p. 493, woodcut), previously named Tristychius 
fimbriatus, T. Stock (Ann. Mag. Nat. Hist. [5] vol. xii. 1883, p. 177, 
pi. vii. fig. 1). — Middle Carboniferous Limestone ; Gilmerton, 
near Edinburgh. [Edinburgh Museum.] Also St. Louis Limestone 
(Lower Carboniferous) ; Alton, Illinois l , 

Ostracacanthus, J. "W. Davis (Rep. Brit. Assoc. 1879, p. 343, and 
Quart. Journ. Geol. Soc. vol. xxxvi. 1880, p. 64), with the single 
species, O. dilatatus, Davis, ibid. 1879, p. 343, and ibid. 1880, 
p. 64, woodcut. — Cannel Coal (Middle Coal-Measures); Tingley, 
Yorkshire. [Collection of J. W. Davis, Esq., Halifax.] 

1 J. S. Newberry, Palaeoz. Fishes N. America (Mon. U.S. Geol. Surv. no. xti. 
1889), p. 203, pi. xxi. fig. 11. 



ICHTIIY0D0RULITK3. 

Pig. 11. 



151 




Harpacanthus fimbriatm (Stock). — M. Carb. Limest., Gilmeiton. (After 
Traquair. ) 

Y. Dermal defences of doubtful position. 

Genus EDESTUS, Leidy. 

[Proc. Acad. Nat. Sci. Philad. vol. vii. 1856, p. 414.] 

Syn. Protopirata, H. Trautschold, Zeitschr. deutsch. geol. Gesell.vol. xl. 
1888, p. 753. 

Spine broad, laterally compressed, elongated and gently arched ; 
convex margin armed with a series of large broad denticles, serrated, 
and enveloped in ganoine : sides of the spine destitute of surface- 
ornament and ganoine, being only marked by oblique transverse 
sulci, each arising from the point of separation of two denticles, and 
often implying the complete division of the spine into a series of 
segments, easily detached one from another ; concave margin with- 
out denticles. No distinct base of insertion. 

Originally regarded as portions of the jaw of a fish by J. Leidy l and 
Newberry 2 , and compared with the rostral prolongation of Pristis by 
L. Agassiz 3 , these remarkable fossils were first suspected to be Elas- 

1 Proc. Acad. Nat. Sci. Philad. vol. vii. (1856), p. 414. 

2 Pal. Illinois, vol. ii. (1866), p. 84. 

3 Proc. Amer. Assoc. Adv. Sci. 1855 (1856), p. 229. 



152 ICHTHYODORULITES. 

mobranch spines by Leidy l and definitely recognized as such by 
Sir Richard Owen 2 . They were also described as spines by New- 
berry and Worthen a ; by Cope 4 and H. Woodward 5 the resemblance 
between their segmented character and that of the Cretaceous Pele- 
eopterus has been pointed out ; and Newberry 6 has recently 




Edestus minor, Newb. — Coal-Measures, Indiana, U.S.A. 

suggested that each spine may correspond to a series of spines such 
as occurs upon the tail of some species of Trygon. Trautschold 7 has 
revived the original hypothesis of Leidy ; and Miss Hitchcock 8 
compares the fossil with the intermandibular arch of the Ganoid 
Onychodus. 

Edestus heinrichsi, Newberry & Worthen. 
1870. Edestus heinrichsii^ Newberry & Worthen, Pal. Illinois, vol. iv. 

p. 350, pi. i. fig. 1. 
1879. Edestus heinrichii, J. S. Newberry, in Ann. Rep. Geol. Surv. 

Indiana, 1876-78, p. 347. 

Form. 8f hoc. Coal-Measures : Illinois and Indiana, U.S.A. 

1 Proc. Acad. Nat. Sci. Philad. vol. viii. (1857), p. 301. 

2 Palaeontology, ed. 2 (1861), p. 123. 

3 Pal. Illinois, vol. iv. (1870), p. 350. 

4 Vert.Cret. Form. West (Rep. U.S. Geol. Surv. Territ. vol. ii. 1875), p. 244 c. 

5 Geol. Mag. [3] vol. in. (1886), p. 6. 

6 Ann. New York Acad. Sci. vol. iv. (1888), p. 120. 

7 Bull. Soc. Imp. Nat. Moscou, 1883, pt. ii. p. 160. 
» Amer. Nat, 1887, p. 847. 



ICHTHTODORTTLITES. 153 

P. 3151. Plaster cast of type specimen described and figured by 
Newberry & Worthen, loc. cit. ; Belleville, Illinois. 

Enniskillen Coll. 

P. 4795. Denticle of spine ; Indiana. Presented by Prof. Hitchcock. 

P. 2231. Smaller denticle ; Indiana. Egerton Coll. 

Edestus minor, Newberry. 

1856. Figure by E. Hitchcock, Proc. Amer. Assoc. Adv. Sci. 18o5, 

p. 229. 
1861. Edestes, R. Owen, Palse ontology, ed. 2, p. 124, woodc. fig. 38. 
1866. Edestus minor, J. S. Newberry, Pal. Illinois, vol. ii. p. 84, pi. iv. 

fig. 24. 
1870. Edestus vorax, Newberry & Worthen (non Leidy), ibid. vol. iv. 

pi. i. fig. 2. 
1879. Edestus minor, J. S. Newberry, Ann. Eep. Geol. Surv. Indiana, 

1876-78, p. 348. 

Form. <$f Loc. Coal- Measures : Indiana, U.S.A. 

40347. Plaster cast of specimen figured by Newberry and Worthen, 
loc. cit., the original being preserved in the Museum of 
Amherst College. Purchased, 1867. 



Edestus davisi, H. Woodward. 

1886. Edestus davisii, H. Woodward, Geol. Mag. [3] vol. iii. p. 1. pi. i. 

Form. Sf Loc. Carboniferous : Gascoyne District, W. Australia. 

P. 5122. Plaster cast of type specimen. 

Made in the Museum, 1886. 

The following species have also been described, but there are no 
examples in the Collection : — 

Edestus giganteus, J. S. Newberry, Ann. New York Acad. Sci. 

vol. iv. (1888), p. 121, pi. vi. fig. 1, andPalseoz. Fishes N. 

America (Mon. U.S. Geol. Surv. no. xvi. 1889), p. 225, 

pi. xli. fig.l. — Coal-Measures ; Mason Co., Illinois, U.S.A. 

[Columbia College, New York.] 
Edestus protopirata, H. Trautschold, Nouv. Mem. Soc. Imp. Nat. 

Moscou, vol. xiv. (1879), p. 49, pi. vi. fig. 8, & Bull. Soc. 

Imp. Nat. Moscou, 1883, pt. ii. p. 169, pi. v. figs. 1, 2 : 

Protopirata centrodon, H. Trautschold, Zeitschr. deutsch. 



154 TCHTCTYODORULITES. 

geol. Gesell. vol. xl. (1888), p. 750, woodc. of micro, sec- 
tions. — Upper Carboniferous Limestone; Government of 
Moscow, Russia. [Trautschold Collection, Breslau. Type 
of Protopirata.~] 
Edestus vorax, J. Leidy, Proc. Acad. Nat. Sci. Philad. vol. vii. 1856, 
p. 414, and Journ. Acad. ISTat. Sci. Philad. [2] vol. iii. 
p. 159, pi. xv. — Carboniferous ; Frozen Rock, Arkansas 
River, Indian Territory, [*\cademy of Sciences, Phila- 
delphia. The type species.] 



Genus CYNOPODIUS, Traquair. 
[Geol. Mag. [2] vol. viii. 1881, p. 35.] 

Small spine-like body with a thin, expanded, spatulate exserted 
portion, and an extremely elongated, narrow, subcylindrical inserted 
portion or base. Surface of exserted portion often coated with a 
thin layer of ganoine, which extends for some distance down one 
aspect of the base ; the margin of this spatulate extremity also often 
coarsely notched or crenulated. 

Cynopodius crenulatus, Traquair. 
[Plate I. fig. 4.] 

1881. Cynopodius crenulatus, R. H. Traquair, Geol. Mag. [2] vol. viii. 
p. 35. 

1882. Cynopodius crenulatus, R. H. Traquair, loc. cit. [2] vol. ix, 
p. 541. 

Type. Edinburgh Museum. 

Form. Sf Loc. Lower Carboniferous : Scottish Coalfield. 

42085. Complete specimen, shown of the natural size in PI. I. fig. 4 ; 
Calciferous Sandstone Series, Pitcorthy Shale Works, near 
Anstruther, Fife. Purchased, 1870. 

P. 2263, P. 4454. Two portions of limestone with several frag- 
ments of this fossil ; Calciferous Sandstone Series, Bur- 
diehouse, near Edinburgh. 

Egerton and Enniskillen Colls. 

P. 2294. Complete specimen ; Carboniferous Limestone (Edge-Coal 
Series), Loanhead, near Edinburgh. 

Presented by Mrs. Burton, 1882. 

P. 4498. Two specimens ; Edge-Coal Series, Borough Lee, near 
Edinburgh. Presented by Dr. R. IT. Traquair, 1884. 



ICHTHY0D0RULITE3. 



155 



Genus EUCTENIUS, Traquair. 
[Geol. Mag. [2] vol. viii. 1881, pp. 36, 334.] 

Small dermal defence somewhat elliptical in shape, laterally com- 
pressed, convex on one side, concave on the other, with one margin 
nearly straight, the opposite margin evenly convex, one extremity 
rounded or bluntly pointed, and the other tapering to a point, or 
produced into a long narrow extension. Convex margin divided 
in a comb-like manner into a series of closely arranged, acutely 
pointed denticles. 

Fossils of this character have been assigned by Anton Fritsch to 
the cloacal region of certain Permian Amphibia under the name of 
" Kammplatten." l 

Euctenius unilateralis (W. J. Barkas). 
1869. Ctenoptychius, T. P. Barkas, Geol. Mag. vol. vi. p. 43, woodc. figs. 
1, 2. 

1873. Ctenoptychius, T. P. Barkas, Coal Meas. Palaeont. p. 18, figs. 
22, 23. 

1874. Ctenoptychius unilateralis, W. J. Barkas, Monthly Rev. Dental 
Surgery, vol. ii. p. 484, figs, xvi, xvii. 

1875. Ctenoptychius unilateralis, J. Ward, [Proc] N. Staffs. Nat. Field 
Club, p. 220. 

1881. " Ctenoptychius " unilateralis, R. H. Traquair, Geol. Mag. [2] 

vol. viii. p. 335. 
1890. Euctenius unilateralis, J. Ward, Trans. N. Staffs. Inst. Mining 

Engineers, vol. x. p. 152, pi. ii. fig. 14. 

Type. Collection of T. P. Barkas, Esq., Newcastle-upon-Tyne. 
The type species. 

Fig. 13. 




Euctenius unilateralis (Barkas). — Coal-Measures, Newcastle-upon-Tyne. 
The upper figure is twice, and the lower figure thrice the natural size. 

Form. <$f Loc. Coal-Measures : Staffordshire, Northumberland, and 
South Scotland. 

3 Fauna der Gaskohle, vol. i. (1880), pi. xx. See also R. H. Traquair, Geol. 
Mag. [2] vol. viii. (1881), p. 334, and T. Stock, Ann. Mag. Nat. Hist, [5] vol. viii. 
(1881), p. 90. 



1 56 ICHTHTODORULITES. 

45028. Typical specimen ; Airdrie, Lanarksbire. Purchased, 1S74. 

P. 443. Broken specimen ; Newsham, Newcastle-upon-Tyne. 

Presented by T. P. Barlcas, Esq., 1882. 

The following species has also been described, but there are no 
examples in the Collection : — 

Euctenius elegans, R. H. Traquair, Geol. Mag. [2] vol. viii. (1881), 

pp. 36, 334 : ' Kammplatten', T. Stock, Ann. Mag. Nat. 

Hist. [5] vol. viii. (1881), p. 90.— Middle Carboniferous 

Limestone (Black-band Ironstone) ; Borough Lee, near 

Edinburgh. [R. H. Traquair Collection.] 

The genus has also been recorded from the Coal-Measures of 

Linton, Ohio, where fine groups of this small ichthyodorulite occur. 

See J. S. Newberry, Paleeoz. Fishes N. America (Mon. U.S. Geol. 

Surv. no. xvi. 1889), p. 228. 

A supposed Elasmobranch fish, from the Kupferschiefer of Thu- 
ringia, is also described as exhibiting several pairs of slender spines 
in the region of the head (C. Giebel, Zeitschr. gesammt. Naturw. 
1856, p. 367, pis. iii., iv.). 

Two undetermined Ichthyodorulites have been named, without 
description, as follows : — 

Cricacanthus jonesi, L. Agassiz, Poiss. Foss. vol. iii. (1843), p. 176 
(name only). — Lower Carboniferous Limestone ; Armagh. 

Gyropristis obliquus, L. Agassiz, ibid. p. 177 (name only); W.King, 
Permian Foss. (Pal. Soc. 1850), p. 222.— (?) Permian ; 
Belfast. 



IXCEET.E SEDIS. 

Fragments of dermal armour, for the most part pertaining to un- 
known primitive types of fishes, from the Upper Silurian of the Is- 
land of Oesel. Baltic Sea, are described by C. H. Pander (Monographie 
der fossilen Fische des Silurischen Systems der russisch-baltischen 
Gouvernements, 1856) under the following names : — ■ 

Coccopeltus asmusi, Pander, op. cit. p. 50, pi. v. fig. 1. 
Cypliomalepis egertoni, Pander, ibid. p. 51, pi. v. fig. 3. 
Dasylepis heyserlingi, Pander, ibid. p. 54, pi. v. fig. 6. 
Dictyolepis bronni, Pander, ibid. p. 56, pi. v. fig. 5, pi. vi. fig. 14. 
Lopholepis schmidti, Pander, ibid. p. 55, pi. v. fig. 4. 
Melittomcdepis efogans, Pander, ibid. p. 60, pi. v. fig. 8. 
Otiiscolepis magna, 0. dentata, 0. serrata, and 0. crenulata, 
Pander, ibid. pp. 58, 59, pi. vi. figs. 32-35. 



CCEL0LEPID2E. 



is: 



Phlebolepis elegans, Pander, ibid. p. 60, pi. v. fig. 12. 

Prionocanthus dubia, Pander, ibid. p. 70, pi. xxi. fig. 21. 

Rytidolepis quenstedti, Pander, ibid. p. 48, pi. v. fig. 2. 

Schidiosteus mustelensis, Pander, ibid. p. 49, pi. v. fig. 13. 

Stigmolepis oiveni, Pander, ibid. p. 53, pi. v. fig. 7. 

Trachylepis formosa, Pander, ibid. p. 52, pi. vi. fig. 22. 

The specimens described as Coccopeltus,Cyphomalepis, Trachylepis, 
and Phlebolepis are regarded as probably referable to Eurypterids 
by E. von Eichwald, Leth. Kossica, vol. i. (1860), p. 1502. 

Here may also be placed the indeterminable fragments of dermal 
armour described under the following names : — 

Chiastolepis clathrata, E. von Eichwald, Bull. Soc. Imp. Nat. 
Moscou, vol. xvii. (1844), p. 831, and ibid. vol. xix. 
(1846), pt. ii. p. 301, pi. x. figs. 18, 19, and Leth. Rossica, 
vol. i. (1860), p. 1565, pi. Ivii. fig. 11.— Devonian ; 
Pawlowsk, St. Petersburg. [University of St. Peters- 
burg.] 

Spirodus regularis, G. Kade, Programm k. Realsehule zu Meseritz, 
] 858, p. 20, fig. 13. — Lower Palaeozoic Boulder ; Silesia. 

Osteoplaoc erosa, F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. ii. 
(1848), p. 6, and Brit. Palseoz. Foss. (1855), p. 613, 
pi. iii. k. fig. 12. — Carboniferous ; Cultra, Co. Down, Ireland. 
[Woodwardian Museum, Cambridge.] 

Sp>henophorus lilleyi, J. S. Newberry, Palseoz. Fishes N. America 
(Mon. U.S. Geol. Surv. no. xvi. 1889), p. 92, pi. xx. 
fig. 15. — Chemung Group ; Bradford Co., Pennsylvania. 
[Columbia College, New York.] 

Callognaihus regularis, J. S. Newberry, ibid. p. 70, pi. xxvii. 
fig. 18. — Huron Shale ; Delaware, Ohio. [Columbia 
College, New York.] 

Callognaihus serratus, J. S. Newberry, ibid. p. 70, pi. xxvii. 
figs. 16, 17. — Cleveland Shale j Lorain Co., Ohio. [Co- 
lumbia College, New York.] 



Family CCELOLEPIDJE. 

Under the group of ' Coelolepiden ' Pander arranges a number of 
minute dermal tubercles, coated with ganoine, usually hollow within, 
and having the external layer separated by a constriction from the 
base. These tubercles consist of cosmine, and the relative size of 
the internal cavity varies considerably, sometimes indeed appearing 
to be absent. 



153 CCELOLEPIDJE. 

Genus CCELOLEPIS, Pander. 
[Foss. Fische Silur. Syst. 1856, p. 66.~] 

Internal cavity of tubercle widely open at the base. 

Of this genus four species are recognized, according to the form 
of the scale and its ornamentation. They are named C. Icevis (p. 66, 
pi. iv. fig. 11, pi. vi. fig. 10), 0. schmidti (p. 66, pi. iv. fig. 12), C. 
goebeli (p. 66, pi. iv. fig. 13), and C. carinata (p. 66, pi. iv. fig. 14, 
pi. vi. fig. 13), and each form is exhibited upon the following 
specimen : — 

P. 6017. Small slab of shelly limestone, with numerous minute, 
ganoid scales ; Upper Silurian, Island of Oesel. 

Presented by Prof. Friedrich Schmidt, 1889. 



Genus THELODUS, Agassiz. 
[Murchison's Silur. Syst. 1839, p. 606.] 

Syn. Pachylepis, C. H. Pander, Foss. Fische Silur. Syst. 1856, p. 67. 
Thelolepis, C. H. Pander, ibid. p. 67. 

Internal cavity of tubercle opening by a minute orifice at the 
base. 

Thelodus parvidens, Agassiz. 

1839. Thelodus parvidens, L. Agassiz, in Murchison's Silur. Syst. 

pp. 606, 704, pi. iv. figs. 34-36. 
1855. Thelodus parvidens, F. M'Coy, Brit. Palaeoz. Foss. p. 576. 
(?) 1856. Pachylepis glaber, C. H. Pander, Foss. Fische Silur. Syst. 

p. 67, pi. iv. fig. 10, pi. vi. figs. 1-6, 8. 
1885. Thelodus parvidens-, F. Roemer ; Palaeont. Abhandl. vol. ii. 

p. 359, pi. xxxi. figs. 21-25. 

Type. Dermal tubercles ; unknown. 

The type species. Tubercles not more than one millimetre in 
diameter, smooth and flattened, quadrate, often with rounded angles, 
sometimes in part fluted. 

Form. Sf Loc. Upper Ludlow Bone-bed : Herefordshire. Upper 
Silurian Boulders : N.E. Germany. (?) Upper Silurian : Isle of 
Oesel, Baltic Sea. 

P. 5099. Fragment of Upper Ludlow Bone-bed filled with the 
tubercles ; Norton, near Onibury, Shropshire. 

Presented by John Edward Lee, Esq., 1885. 



PTERASPID^. 



159 



A scale from the Oesel limestone, differing only from the above in 
the coarse crimping of two sides, is named Pachylepis costata, C. H. 
Pander, op. cit. p. 67, pi. vi. fig. 9. 

Other dermal tubercles, apparently of the Ccelolepidae and closely 
related to the above, are described thus: — 

Gomphodus sandelensis, C. H. Pander, op. cit. (1856), p. 76, pi. vi. 

figs. 15-17. — Upper Silurian ; Oesel. 
Nostolepis striata, C. H. Pander, ibid. p. 68, pi. vi. fig. 7. — Ibid. 



Subclass III. OSTRACODERMI. 

Exoskeleton well developed, the head and anterior portion of the 
trunk being covered with plates ; mouth destitute of hard parts. 
Arches for support of an appendicular skeleton rudimentary or 
absent. Notochord persistent. 



Order I. HETEROSTRACI. 

Exoskeleton consisting of calcifications without bone- corpuscles ; 
each plate comprising three superposed layers — an inner "nacreous " 
layer of lamella?, a relatively thick middle zone of polygonal 
cancellae, and an outer hard layer of vaso-dentine. Dermal sense- 
organs well-developed, arranged in canals traversing the middle 
layer of the shield and opening by a double series of pores externally. 
Dorsal shield of few pieces, firmly united in the adult; ventral 
shield simple; [jaws never preserved] ; orbits wide apart and laterally 
placed. Paired appendages absent. 

In this order is included a single family, that of the Pteraspidae. 



Family PTERASPIDAE. 

External layer of each dermal shield forming an ornament of very 
fine, concentric, closely arranged ridges, parallel with the outer 
margin. Rostral region relatively small. Scales of caudal region, 
when present, numerous and rhomboidal. 



1 60 HETEROSTRACI. 

Synopsis of Genera. 

I. Orbits enclosed in dorsal shield. 

Shield consisting of seven parts, fused in adult. Pteraspis (p. 160). 

II. Orbits forming lateral notches in dorsal shield. 

Shield consisting of a single plate Palcsaspis (p. 169). 

Shield consisting of four parts , Cyathaspis (p. 170). 



Genus PTERASPIS, Kner & Huxley. 

[R. Kner, Haidinger's Naturw. Abhandlungen, vol. i. 1847, p. 165 ; 
emend. T. H. Huxley, Quart. Journ. Geol. Soc. vol. xvii. 1861, 
p. 166.] 

Syn. Palceoteuthis, F. Roerner, Palaeontogr. vol. iv. 1855, p. 72. 

Archceoteuthis, F. Roemer, in Bronn's Leth. Geognostica, vol. i. 

1855, p. 520. 
Scaphaspis, E. R. Lankester, Rep. Brit. Assoc. 1864 (1865), Trans. 

Sect. p. 58 (in part). 

Dorsal shield arrow-head-shaped, consisting of seven separately 
calcined portions : — a large central disc, with a triangular azygous 
rostral jplate anteriorly and a large median dorsal spine posteriorly ; 

Fig. 14. 




Pteraspis rostrata (Ag.). — Dorsal shield restored, after Lankester. 

a pair of orbital plates, completely enclosing the orbit on either side 
and partially inserted between the rostrum and central disc ; and a 



PTERASPIDJE. 161 

pair of postero-lateral cornua, each pierced with a large [? branchial] 
foramen. [? Pineal body occupying] a pit on the inferior aspect of 
the dorsal shield between the orbits. Yentral shield consisting of 
a single convex plate (" Scaphaspis "). Caudal region with small 
rhomboidal scales, slightly overlapping, and ornamented with few, 
delicate, imbricating ridges, parallel to the overlapped anterior 
margins. 

The generic name Pteraspis was originally applied by Kner to the 
simpleshields named Cephalaspis hivisii and C. lloydii by Agassiz, 
in conjunction with similar fossils from Galicia, these being all re- 
garded as not pertaining to fishes, but most nearly paralleled by the 
internal shell of the Cephalopod, Sepia. The dermal nature of the 
specimens and their correct reference to chordate animals was subse- 
quently determined by Huxley x , who altered the significance of the 
generic term by regarding as type the complex shield described 
by Agassiz as Cephalaspis rostratus. Huxley's determination was 
adopted and extended by Ray Lankester 2 , who published the accom- 
panying restoration of the dorsal shield (fig. 14), and generically 
separated the original type species of Kner's Pteraspis under the 
name of Scaphaspis. The simple shields are now proved to be the 



Fig. 15. 




Pteraspis rostrata (Ag.). — Side Tiew of partially restored fish. 

ventral armature of the animals covered dorsally by the more com- 
plex shields 3 ; and Scaphaspis thus becomes in part a synonym of 
Pteraspis, as finally amended. 

The anterior scales of the caudal region are known only in one 
specimen (No. 44116, p. 163). 



1 Quart. Journ. Geol. Soc. vol. xiv. (1858), p. 277. 

2 See especially " Fishes Old Red Sandst." pt. i. (Mon. Palasont. Soc. 1868), 
p. 28. 

3 A. von Alth, "Ueber die Zusaramengehorigteit der den Fischgattungen 
Pteraspis, Cyathaspis, und Scaphaspis zugesohriebenen Schilder" (Beitr. 
Palaont. Oesterr.-TJngaras, vol. v. 1886), p. 61, pi. xxiv. 

PART n. M 



162 HETEROSIRACI. 

Pteraspis rostrata (Agassiz). 
[Plate IX. fig. 1.] 

1835. Cephalaspis rostratus, L. Agassiz, Poiss. Foss. vol. ii. pt. i. p. 148, 

pi. i. b. figs. 6, 7. 
1861. Pteraspis rostratus, T. H. Huxley, Quart. Journ. Geol. Soc. 

vol. xvii. p. 165, woodc. 
1865. Pteraspis rostratus, E. R. Lankester, "Rep. Brit. Assoc. 1864, 

Trans. Sect. p. 58. 
1868. Pteraspis rostratus, E. R. Lankester, Fishes Old Red Sandst. 

pt. i. (Pal. Soc), p. 32, pi. iv. figs. 1-3, 7, 8, pi. v. fig. 4, pi. vi. 

figs. 1-3, 6, 9, pi. vii. figs. 3, 5, 7, 9, 10, 12, 13, 19. 

Type. Dorsal shield ; olim Sir R. I. Murehison's Collection. 

Rostrum obtuse, its maximum width being three quarters as great 
as its length, and the superior aspect marked with a longitudinal, 
broad flattening or shallow groove. Disc oblong, less than twice as 
long as broad, with parallel sides, very convex transversely, and 
tapering abruptly posteriorly ; dorsal spine large ; cornua abruptly 
truncated. 

This is the type species and is the largest known form, the dorsal 
shield sometimes attaining a total length of 0*14. The ventral shield 
is probably described as Scaphaspis lloycli. 

Form. § Log. Lower Old Red Sandstone : Herefordshire, 
Monmouthshire, and Glamorganshire. 

P. 4110-11. Tw T o very large imperfect specimens, partly in counter- 
part, displaying the orbits and the pineal pit, and probably 
not less than 0*14 in length when complete ; Great Skirrid 
Quarry and Gethlellydd, near Abergavenny. 

Presented by Dr. D. M. McCidlough, 1883. 

P. 5038. Smaller splintered example; Gethlellydd. 

Presented by John Edward Lee, Esq., 1885. 

P. 5034-37. Shield as large as Nos. P. 4110-11, in counterpart, and 
three imperfect median discs of similar specimens ; Gold- 
tops, near Newport, Monmouthshire. The fourth specimen 
seems to show the natural form of the disc, extremely 
arched from side to side ; its transverse section is given in 
the outline, PI. IX. fig. 1. 

Presented by John Edward Lee, Esq., 1885. 

P. 5373. Two imperfect smaller shields, one showing the ornamenta- 
tion of the rostral plate ; Cradley, near Malvern. 

Purchased, 1887. 



pteraspid^;. 163 

P. 3242, P. 4218. Two blocks of sandstone with fragmentary shields, 
and an imperfect specimen, inner aspect ; Cradley. 

Ennislcillen Coll. 

P. 680-1. Anterior half of shield, and block with portions of 
three specimens, two showing the dorsal spine in position ; 
Cradley. Egerton Coll. 

43969. Well-preserved portions of disc and dorsal spine, figured by 
Lankester, op. cit. pi. vi. fig. 6 ; Cradley. 

Purchased, 1872. 

36177, 36186, 36189. Three imperfect shields, about 0*09 in length '> 
Cradley. Purchased, 1861. 

35978. Portion of disc and dorsal spine, inner aspect, as convex as 
no. P. 5037 ; near Ludlow. Purchased, 1861. 

45983 a. Portion of disc and dorsal spine ; Whirbatch. 

Lightbody Bequest. 

45963. Much fractured shield ; Targrove, near Ludlow. 

Lightbody Bequest. 

41845. Impression of inner aspect of shield, and portion of dorsal 
spine; Herefordshire. Purchased, 1869. 

P. 4112. Relatively broad, small disc, probably of this species ; 
Pandy, near Abergavenny. 

Presented by Dr. D. M. McCullough, 1883. 

45961. Well-preserved fragment of disc, probably of this species; 
Herefordshire. Lightbody Bequest. 

38035. Disc of a young individual, probably of this species ; 
Heightington. Purchased, 1864. 

42150. Similar specimen ; (?) Heightington. Baugh Coll. 

42148, 42163. Three orbital plates, either of this species or P. 
croucJii ; (?) Heightington. Baugh Coll. 

44116. Small specimen showing fragments of the anterior shields, 
and some of the scales of the caudal region naturally 
arranged ; Cradley. This fossil is described and figured by 
E. 11. Lankester in the Quart. Journ. Geol. Soc. vol. xx. 
(1864), p. 194, pi. xii. figs. 1-4, 6, 7, and subsequently 
noticed in the " Pishes Old Eed Sandst." pt. i. (Pal. Soc. 
1868), p. 31, pi. v. figs. 3, 5, 8, as possibly referable to 
P. crouchi. It is determined to be the dorsal portion of 

m 2 



164 , JIETEROSTRACI. 

the fish, showing the scar for the insertion of the spine at 
the hinder extremity of the shield. To the present writer, 
however, recent discoveries on the Continent suggest 
another and more probable explanation of the specimen. 
The scales appear to be referable to the flank, the so-called 
dorsal ridge-scales of Lankester not being so clearly dis- 
tinguished from the other scales as indicated in the original 
description, and being truly referable to the middle of the 
flank. The supposed " scar " for the insertion of the spine 
seems to the present writer to be the line of separation 
between the dorsal and ventral shields • and a small pos- 
tero-lateral portion of the dorsal shield remains above, 
while the greater portion of the hinder extremity of the 
ventral shield is preserved below. The latter exhibits the 
broad, longitudinal median convexity characteristic of the 
so-called Scapliaspis lloydi, and this is continued back- 
wards by a series of calcifications which have much more 
the appearance of ridge-scales than those determined as 
such by Lankester. In this manuer, the re-entering angle 
at the hinder margin of the armoured portion of the body 
is more easily explained than by the accidental crushing 
required in the original interpretation of the fossil. 
Moreover, the slight longitudinal mark on the fragment of 
shield bounding each margin of the supposed dorsal "scar " 
is paralleled by a similar mark observed near the lateral 
margin of several shields both of Pteraspis and " Sca- 
phaspis," while the median portion of the inner surface of 
the shield is always smooth and even. 

Presented by Prof. E. Ray Lankester, 1873, 

The undermentioned ventral shields are probably referable to 
Pteraspis rostrata. They were described by Agassiz under the 
names of Cephalaspis lewisii 1 and C. lloydii 2 , subsequently made 
the type of Pteraspis by Kner 3 , and finally regarded as the type of 
Scapliaspis by Lankester, under the name of S. lloydii 4 . 

P. 5861. Internal cast of a fine, uncrushed specimen, 0*125 in length, 

1 Poiss. Foss. vol. ii. pt. i. (1835), p. 149, pi. i. b. fig. 8. 

2 Ibid. p. 150, pi. i. b. figs. 9-11. 

3 Haidinger's Naturw. Abhandl. vol. i. (1847), p. 159, pi. v. 

4 E. E. Lankester, Rep. Brit. Assoc. 1864, Trans. Sect. p. 58, and Fishes Old 
Red Sandst. pt. i. (Pal. Soc. 1868), p. 20, pi. i., pi. vii. figs. 1, 6, 17, 18. A 
shield, wanting the posterior extremity, from the Upper Silurian of Iwanie, 
Galicia, is assigned to this "species" by A. von Alth, Abhandl. k. k. geol. 
Keichsanst. vol. vii. pt. i. (1874;, p. 49. pi. ii. fig. 2. 



riERAsrin.E. 165 

shown of two-thirds the natural size in PI. IX. fig. 2, and 
employed in the woodcut- restoration, fig. 15 (p. 161); 
Kentchurch Hill, near Pontrilas, Herefordshire. This is 
apparently the only uncrushed specimen in the collection, 
and, as shown by the figures, proves the diagrammatic 
longitudinal section of ' Scaphaspis lloydii ' of Lankester 
(op. eit. pi. vii. fig. 15) to be too much arched posteriorly, 
while the published transverse section (ibid. fig. 18) 
applies only to the hinder third of the shield. 

Presented by J. F. Symonds, Esq., 1889. 

46565-68. Two imperfect specimens, about O09 in length, the first 
showing some well-preserved fragments of the shield itself ; 
Cradley. Purchased, 1875. 

46875. Similar shield, in counterpart ; Cradley. Purchased, 1875. 

P. 682. Anterior half of shield, inner aspect ; probably from Crad- 
ley. Egerton Coll, 

P. 4218 a. Small shield, inner aspect, probably from Cradley. 

Ennislillen Coll. 

P. 4105, P. 4113-14. Two small specimens, and the anterior half 

of a third, apparently in the same matrix as the small 

dorsal shield, No. P. 5038 ; Gethlellyd, near Abergavenny. 

Presented by Dr. D. i¥. McCullough, 1883. 

P. 4105, P. 4105 a. Three detached specimens, and one imperfect 
example associated with part of a median dorsal disc of 
Pteraspis ; Pandy, near Abergavenny. 

Presented by Dr. D. M. McCullourjh, 1883. 

45980. Typical specimen, O07 in length ; Abergavenny. 

Lightbody Bequest. 

P. 5039. Imperfect shield, 0-1 in length ; Star Pitch. 

Presented by John Edward Lee^ Esq., 1885. 

P. 5041. Imperfect shield, inner aspect ; Newbridge, Glamorgan- 
shire. Presented by John Edward Lee, Esq., 1885. 

P. 5046. Imperfect cast of shield, 0*05 in length ; Newport, Mon- 
mouthshire. Presented by John Edward Lee, Esq., 1885. 

45950. Well-preserved specimen, figured by Lankester, op. cit. pi. i. 
fig. 8 ; Hayton's Bent, near Ludlow. 

Lightbody Becpiest. 



16*0 HETEROSTRACI. 

45950 a. More imperfectly preserved shield, apparently from the 
same horizon and locality. Lighibody Bequest. 

45955. Internal cast and fragments of small shield ; Downton Hall, 
near Ludlow. Lightbocly Bequest. 

P. 3245. Internal cast and fragments of small shield ; Leominster. 

Ennislcillen Coll. 

42153. Crushed and broken specimen ; locality unknown. 

Baugh Coll. 

46876. Internal cast of very broad, flattened specimen, doubtfully 
of this species ; Cradley. Purchased, 1875. 

P. 193. Anterior two-thirds of similar specimen; Heigh tington. 

Weaver-Jones Coll. 

42159-60. Three very small shields, doubtfully of this species ; near 
Trimpley, Worcestershire. Baugh Coll. 

38034. Two similar, but somewhat larger, shields, associated, and 
showing portions of the external surface ; Trimpley. 

Purchased, 1864. 

An imperfectly known species, of large size, apparently closely 
related to Pteraspis rostrata, has been obtained from the uppermost 
Silurian and Lower Devonian of Galicia, and described under the 
name of Pteraspis major, A. von Alth, Abhandl. k. k. geol. Beichs- 
anstalt, Wien, vol. vii. pt. i. (1874), p. 44, pi. i. figs. 1-4, pi. iii. 
figs. 3-5 \ The following specimen may be referable to this 
form : — 

P. 6099. Portions of dorsal and ventral shields in natural apposition, 

the dorsal showing the posterior spine ; Upper Ludlow, 

Bilcze-on-Sered, Galicia. From the Alth Collection. — 

Presented by Prof. W. Szajnocha, 1888. 

It is interesting to note that the supposed ventral shield of P. 
rostrata has already been recorded by v. Alth from the Upper Silu- 
rian of Galicia (sttpra, p. 164, footnote). 



1 If the undetermined specimen described and figured in Alth's memoir (p. 71, 
pi. v. fig. 33) pertain to this species, as suggested, the broad, rounded character 
of the rostra region suffices to distinguish it from P. ro:<truta. 



PTERASPIDJ5. 



167 



Pteraspis crouchi, Laukester. 

1865. Pteraspis crouchii, E. R. Lankester (ex Salter, MS.), Rep. Brit. 

Assoc. 1864, Trans. Sect. p. 58. 
1868. Pteraspis crouchii, E. R. Lankester, Fishes Old Red Sandst. pt. i. 

(Pal. Soc), p. 30, pL iii., pi. iv. fig. 5, pi. vi. figs. 4, 7, 8, pi. vii. 

figs. 4, 8, 11. 
1887. Pteraspis crouchii, A. S. Woodward, Proc. Zool. Soc. p. 478, 

wo ode. 

Type. Dorsal shields ; British Museum, Ludlow and Oxford 
Museums. 

Rostrum slender and acutely pointed, upwardly curved, its maxi- 
mum width being about half as great as its length. Disk oblong, 
heart-shaped, abruptly tapering posteriorly ; dorsal spine large ; 
cornua large and broad, obtusely pointed. 

This is a smaller species than Pi rostrata, and its ventral shield is 
probably described as Scaphaspu recta. 

Form. Sf Loc. Lower Old Red Sandstone (Cornstones) : Whitbatch 
and Ludlow, Herefordshire, and Abergavenny, Monmouthshire. 

33317 a, b. Two imperfect median discs ; Ludlow. 

Purchased, 1858. 

45954, 45956. Two imperfect discs, one with fragments of the 
spine ; Downton Hall. Lightbody Bequest. 

P. 3246. Internal cast and fragments of disc ; near Ludlow. 

EnnisTcillen Coll. 

45941-42. Two portions of rostrum figured by Lankester, op. cit, 
pi. iii. figs. 12, 13 ; Leyster's Pole. Lightbody Bequest. 

45967. Imperfect rostrum, dorsal aspect, figured ibid. pi. vi. fig. 7 ; 
Short AVood, near Ludlow. Lightbody Bequest. 

45951, 45965. Eractured rostrum from Hayton's Bent, and a frag- 
ment from Downton Hall. Lightbody Bequest. 

42163. Imperfect disc, doubtfully of this species ; Herefordshire. 
The specimen shows the sensory canals injected with 
mineral matter, and is described and figured by the pre- 
sent writer, loc. cit., the figure being reproduced iu the 
accompanying woodcut (fig. 16). Baugh Coll. 

The undermentioned ventral shields are probably referable to 



168 HETEROSTRACI. 

Pteraspis crouch i. They are described under the name of Scapliaspis 
rectus, Lankester 1 , and are relatively longer and narrower than the 
shields named S. lloydi, with more nearly parallel sides. 




Pteraspis crouch), Lank. — Portion of shield, dorsal aspect, showing sensory- 
canals. [No. 42163.] From Proc. Zool. Soc. 1887. 

37389. Imperfect specimen associated with a fragment of the shield 
of Phlyctcmaspis ; Heigh tiugton. Purchased, 1863. 

42149-50. Pour imperfect specimens ; Heightington. Baugh Coll. 

38034 a. Internal cast of shield, figured by Lankester, op. cit. pi. ii. 
fig. 7 ; Worcestershire. Purchased, 1864. 

P. 4107-8. Two specimens ; Asylum Quarry, Abergavenny. 

Presented by Dr. D. M. McCullough, 1883. 

P. 4109. Internal cast of small shield ; from boulder in railway- 
cutting, jVIaincliff, Abergavenny. 

-Presented by Dr. D. M. McCullough, 1883. 

The following species of Pteraspis have also been described, but 
there are no examples in the Collection : — 

Pteraspis angustata, A. von Alth, Abhandl. k. k. geol. Eeichsanst. 
vol. vii. pt. i. (1874), p. 45, pi. i. fig. 11, pi. iii. figs. 6, 7. — 
Lower Devonian ; Iwanie and Kriszczatek, Galicia. [Im- 
perfect shields.] 

Pteraspis mitchelli, J. Powrie, Geologist, vol. vii. (1864), p. 172 ; 
E. E. Lankester, Fishes Old Eed Sandst. pt. i. (Pal. Soc. 

1 Fishes Old Eed Sandst. pt. i. (Pal. Soc. 1868), p. 23, pi. ii. figs. 5-8, 12, 
13, pi. vii. fig. 2. 



PTEKASPIDJ3. 169 

1868), p. 33, pi. v. figs. 1, 2, 6, 10, 11 : Pteraspis, 

H. Mitchell, Geologist, vol. vii. (1864), p. 117, woodc. — 

Lower Old Red Sandstone ; Forfarshire. [Internal cast 

of shield; Dundee Museum.] 
Pteraspis podolica, A. von Alth, loc. cit. p. 42, pi. i. figs. 5-10, 

pi. ii. fig. 1. — Upper Ludlow ; Zaleszczyki, Kriszczatek, 

and Dobrowlany, Galicia. [Shields, wanting rostrum, but 

with relatively large cornua, 
Pteraspis rhenana, C. Schliiter, Sitzungsb. niederrhein. Ges., Bonn, 

1887, p. 125. — Lower Devonian ; near Bonn. [Portion 

of median disc ; University of Bonn.] 

The impression of the inner aspect of an imperfect median disc of 
Pteraspis from the Upper Silurian (or Lower Devonian) of Galicia is 
named " Pterichthys ? " by R. Kner, Haidinger's Naturw. Abhandl. 
vol. i. (1847), p. 167, pi. v. fig. 3 : see also Scaphaspis kneri, p. 174. 

Genus PALJEASPIS, Claypole. 
[Amer. Naturalist, vol. xviii. lo^i, p. 1224.] 

Syn. Holaspis, E. R. Lankester {non J. E. Gray, 1863), Geol. Mag. 
vol. x. 1873, p. 242. 

Scaphaspis, E. R. Lankester, Rep. Brit. Assoc. 1864 (1865), 
Trans. Sect. p. 58 (in part). 

Dorsal shield resembling that of Pteraspis in form, but apparently 
consisting of a single plate and destitute of a median dorsal spine. 
Orbits forming notches in the shield at the base of the rostrum, not 
completely enclosed. 

This genus was first defined by Lankester under the preoccupied 
name of Holaspis, and the type species is P. sericea. 

Palaeaspis sericea (Lankester). 

1873. Holaspis sericeus, E. R. Lankester, Geol. Mag. vol. x. pp. 241, 
331, pi. x. and woodc. 

Type. Dorsal shield ; British Museum. 

Shield narrow and elongated, the rostral region sharply rounded 
and much broader than long; lateral margins, when uncrushed, 
apparently bulging outwards immediately behind the orbits, nearly 
parallel in the hinder half ; posterior margin angulated mesially. 

Form. Sf Loc. Lower Old Red Sandstone (Cornstones) : Aberga- 
venny, Monmouthshire. 

P. 4117. Type specimen described and figured by Lankester, loc. cit. 
Presented by Dr. D. M. McCidlouyh, 1883. 



170 UETKROSTIUCI. 

Palseaspis americana. Claypole. 

1 v< 4. Pahra.pis americana (? and P. bitruncata), E. W. Claypole, Amer. 

Naturalist, vol. xviii. p. 12:24. 
1885. Pakeaspis americana, E. W. Claypole, Quart. Journ. Geol. Soc. 

vol. xli. p. 62, woodc. fig. 7. 
(?) 1885. Palccaspis bitrancata, E. W. Claypole, ibid. p. 62, woodc. 

fig. 8. 

Type. Imperfect dorsal shield ; Museum of Buchtel College, Akron, 
Ohio. 

A species known only from imperfect specimens, as yet incapable 
of precise definition, but apparently distinguished from P. sericea by 
the more regularly ovate form of the shield and the slightly more 
obtuse rostrum. 

The form named bitruncata is not improbably the ventral shield 
of this species. 

Form. § Loc. Onondaga Group : Perry Co., Pennsylvania. 

P. 6132. Imperfect internal cast of shield. 

Presented by Prof. E. W. Claypole, 1890. 

P. 6133. Several fragments. 

Presented by Prof. E. W. Claypole, 1890. 

Genus CYATHASPIS, Lankester. 

[Rep. Brit. Assoc. 1864 (1865), Trans. Sect. p. 58.] 

Syn. Diplaspis, G. F. Matthew, Bull. Nat. Hist. Soc. New Brunswick, 
no. vi. 1887, p. 69. 
Scaphaspis, E. R. Lankester, Rep. Brit. Assoc. 1864 (1865j, 
Trans. Sect. p. 58 (in part). 

Dorsal shield oval, consisting of four separately calcified portions 
— a large central disc, with a short azygous rostral plate anteriorly, 
and a pair of large cornua on the sides. Orbits not completely 
enclosed in the shield. 

In the so-called Diplaspis, and in Cyathaspis integer, the dorsal 
and ventral shields have been found in natural association ; and a 
Scaphasjus-shs-iped shield occurs in the same beds as the type species. 
Until confirmatory evidence is obtained, we venture to regard the 
transverse division of the lateral cornua in Diplaspis as accidental. 

Cyathaspis banksi (Huxley & Salter). 

[Plate IX. fig. 3.] 

1856. Pteraspis banksii, Huxley & Salter, Quart. Journ. Geol. Soc. 
vol. xh. p. 100 ; pi. ii. fig. 2. 



PTERASPID^E. 



171 



1858. Pteraspis banksii, T. II. Huxley, ibid. vol. xiv. p. 274, pi. xv. 
1865. Cyathaspis banksii, E. R. Lankester, Rep. Brit. Assoc. 1864, 

Trans. Sect. p. 58. 
1868. Cyathaspis banksii, E. R. Lankester, Fishes Old Red Sandst. 

pt. i. (Pal. Soc.) p. 26, pi. ii. figs. 9-11, pi. iv. fig 6. 

Type. Dorsal shield ; unknown. 

The type species, the dorsal shield attaining a length of about 
0'05. Median disc oblong, strongly arched from side to side, trun- 
cated posteriorly, with a very small median spine ; rostrum very 
short and broad ; lateral cornua extending from the orbits back- 

Fig. 17. 




Outline of dorsal shield of Cyathaspis, restored by Laukester. 
c, cornua; d., median disc; o., orbit; r., rostral plate; s., dorsal spine. 



wards, broadest mesially, tapering behind, and not projecting beyond 
the posterior margin of the disc. Superficial striae fine, those of the 
rostrum transverse, the others longitudinal, and those of the disc 
partially subdivided into groups by irregular longitudinal costae. 

Form. § Loc. Upper Ludlow and Downton Sandstone : Here- 
fordshire. 

45939. Small slab of Downton Sandstone, with casts of four im- 
perfect shields, one figured by Lankester, op. cit. pi. iv. 
fig. 6 ; Bradnor Hill, Kington. Lighibody Bequest. 

P. 684, P. 683. Ferruginous fossil shield, showing the coarse longi- 
tudinal costae of the disc with intervening fine striae ; also 
a cast of the inner aspect of part of a similar specimen 
displaying some of the supposed branchial excavations and 
the pineal pit; Downton Sandstone, Kington. 

Egerton Coll. 



172 I1RTER0STRAC1. 

P. 3240. Two typical specimens preserved in ferruginous matter; 
Kington. Enniskillen Coll. 

P. 3241. Well-preserved fragments of an apparently uucrushed 
shield, the ornamentation of part of the disc being shown, 
of twice the natural size, in PI. IX. fig. 3 ; Upper Silu- 
rian Bone-bed, Martel, near Ledbury. Enniskillen Coll. 

The so-called Scaphaspis truncatus l or Pteraspis truncatus 2 ap- 
pears to the present writer to be founded in part upon the detached 
median discs of Cyathaspis banksi, and in part upon ventral, shields 
that may probably be referred to this species. The following are 
specimens of this character : — 

P. 683 a. Shield preserved in ferruginous matter, and the anterior 
half of a similar specimen ; Downton Sandstoue, Kington. 

Egerton Coll. 

P. 3243. A complete, apparently uncrushed specimen, similarly pre- 
served; Kington. Enniskillen Coll. 

42158. Impression of shield showing ornament ; locality unknown. 

Baugh Coll. 

P. 3244. Well-preserved fragment of shield, perhaps of this species ; 
Ludlow Bone-bed, Ludford Lane, Ludlow. 

Enniskillen Coll. 



Cyathaspis macculloughi, sp. nov. 
[Plate IX. fig. 4.] 

Type. Imperfect dorsal shield : British Museum. 

Median disc oblong, relatively narrow ; rostrum very short and 
broad ; lateral cornua extending from the orbits backwards, broadest 
mesially. Superficial striae relatively coarse, those of the disc uniform 
and not interrupted with longitudinal costee. 

Form. Sf Log. Lower Old Eed Sandstone : Herefordshire. 

P. 4797. The type specimen, shown, of the natural size, in PI. IX. 
fig. 4 ; England's Hill Quarry, Bodenham. A large por- 
tion of the shield is preserved, being exposed from the 

1 E. E. Lankester, Fishes Old Eed Sandst. pt. i. (Pal. Soc. 1868), p. 24, 
pi. ii. figs. 1-3. 

2 Huxley & Salter, Quart. Journ. Geol. Soc. vol. xii. (1856), p. 100. pi. ii. 
fig.l. 



pteeaspid^:. 173 

inner aspect ; and parts of the ornamented external sur- 
face are also seen in impression. The pineal pit and the 
pair of > -shaped depressions on the inner face of the 
shield immediately behind are conspicuous. 

Presented by Sir Richard Owen, K.C.B., 1884. 

The following species of Cyathaspis have also been described, but 
there are no examples in the Collection : — 

Cyathasjpis acadica : Pteraspis acadica, G. F. Matthew, Canadian 
llecord of Science, vol. ii. (1886), p. 251 : Biplaspis 
acadica, G. E. Matthew, Bull. Nat. Hist. Soc. New Bruns- 
wick, no. vi. (1887), p. 69, woodc, and Trans. Roy. Soc. 
Canada, vol. vi. sect. iv. (1888), p. 49, pi. iv. figs. 1-4. — 
Upper Silurian (Division 2) ; Westfield, New Brunswick. 
[The type species of Diplaspis.~] 
Cyathaspis integer, A. Kunth, Zeitschr. deutsch. geol.Ges. vol. xxiv. 
(1872), p. 7, pi. i. figs. 1-6 ; Jentzsch, ibid. vol. xxxi. 
(1879), p. 793 ; F. Boemer, Palaeont. Abhandl. vol. ii. 
(1885), p. 378, pi. xxxiii. fig. 1. — Upper Silurian (erratic 
block) ; Schoneberg, near Berlin, and Bromberg. [Berlin 
University Museum.] 
(?) Cyathaspis schmidti, F. E. Geinitz, Zeitschr. deutsch. geol. Ges. 
vol. xxxvi. (1884), p. 857, pi. xxx. ; F. Roemer, Palaeont. 
Abhandl. vol. ii. (1885), p. 379. — Upper Silurian ; 
Rostock. [Rostock University Museum.] [? Paloeaspis.~\ 
Cyathaspis sturi, A. von Alth, Abhandl. k.k. geol. Reichsanst. 
vol. vii. no. 1 (1874), p. 46, pi. v. figs. 1-3. — Upper Silu- 
rian ; between Doroschoutz and Wasileu, on the Dniester, 
Galicia. [Dorsal shield ; Imperial Geol. Survey, Vienna.] 
(?) Cyathaspis symondsi, E. R. Lankester, Rep. Brit. Assoc. 1864, 
Trans. Sect. p. 58, and Fishes Old Red Sandst. pt. i. (Pal. 
Soc. 1868), p. 27, pi. vi. fig. 5. — Lower Old Red Sandstone 
(Cornstones) ; Herefordshire. [Internal cast of dorsal 
shield ; Museum of Practical Geology.] 

To Cyathaspis may also probably be referred the ventral shields 
described as follows : — 

Scaphaspis ludensis, E. R. Lankester, Fishes Old Red Sandst. pt. i. 
(Pal. Soc. 1868), p. 25, pi. ii. fig. 4 : Pteraspis ludensis, J. 
W. Salter, Ann. Mag. Nat. Hist. [3] vol. iv. (1859), p. 45, 
woodc. fig. 1. — Lower Ludlow: Church Hill, Leintwardine. 
Upper Ludlow ; near Ludlow. [Shield : Mus. Pract. 
Geol.l 



174 HETEROSTRACI. 

Several ventral shields of Pteraspidians, not hitherto generically 
determined, have received the names mentioned below. The 
majority are probably referable to Pteraspis, and of the first the 
specimen described by Eoemer in 1858 is preserved in the 
Collection (36047. Purchased, 1861). 

Scaphaspis dunensis, E. E. Laukester, Fishes Old Eed Sandst. 
pt. i. (18C8), p. 20, woodc. fig. 10: Pteraspis dunensis, 
T. H. Huxley, Quart. Journ. Geol. Soc. vol. xvii. (1861), 
p. 163 : Palceoteuthis dunensis, F. Eoemer, Zeitschr. 
deutsch. geol. Ges. vol. vi. (1854) p. 650, and Palaeonto- 
graphica, vol. iv. (1855), p. 72, pi. xiii. : Archceoteuthis 
dunensis, F. Eoemer, in Bronn's Leth. Geoguost. (1855), 
p. 520, and Xeues Jahrb. 1858, p. 55 : ? Scaphaspis bon- 
nensis, C. Schliiter, Sitzungsb. niederrhein. Ges. Bonn, 
1887, p. 125. [Imperfect shield ; University of Bonn.] — 
Lower Devonian ; Eifel. [Imperfect shield, wanting 
external layer.] 

Scaphaspis elongata, A. von Alth, Abhandl. k. k. geol. Eeichs- 
anst. vol. vii. no. 1 (1874), p. 51, pi. ii. fig. 4. — Upper 
Silurian (red sandstone) ; Wojskie, Galicia. 

Scaphaspis haueri, A. von Alth, ibid. p. 50, pi. iv. figs. 6, 7. — 
Upper Silurian and Lower Devonian ; Iwanie, Galicia. 
[Imperial Geol. Survey, Vienna.] 

Scaphaspis hieri, E. E. Lankester, Fishes Old Eed Sandst. pt. i. 
(Pal. Soc. 1868), pp. 2, 19, 20, woodc. fig. 9, and Geol. Mag. 
vol. vii. 1870, p. 398 ; A. von Alth, Abhandl. k. k. geol. 
Eeichsanst. vol. vii. no. 1 (1874), pp. 48, 75, pi. ii. figs. 3, 
5, 7, 8 : Pteraspis sp.,E.Kner, Haidinger's iSaturw. Abhandl. 
vol. i. (1847), p. 160, pi. v. figs. 1, 2 (?4) : Palceoteuthis 
Tcneri, E. von Eicl^wald, Analecta Zool. u. Palaeont. Euss- 
lands (1871), p. 5 : Pteraspis kneri, A. Kunth, Zeitschr. 
deutsch. geol. Ges. vol. xxiv. (1872), p. 7 ; F. Schmidt, 
Yerhandl. russ.-kais. mineral. Ges. St. Petersburg, [2] 
vol. viii. (1873), pi. v. figs. 1-8 (doubtfully assigns to this 
species portions of the dorsal shield of a typical Pteraspis, 
compared with P. crouchi by E. E. Lankester, Geol. Alag. 
[2] vol. i. ] 874, p. 288).— Upper Silurian ; Galicia. [Im- 
perial Museum, Vienna.] 

Scaphaspis nathorsti, E. E. Lankester, Kongl. Svenska Vetensk.- 
Akad. Handl. vol. xx. no. 9 (1884), p. 5, pi. i. figs. 1-3.— 
Lower Devonian ; Dickson Bay, Spitsbergen. [Eoyal 
State Museum, Stockholm.] 



PTERASPIDJS. 175 

Scaphaspis obovata, A. von Alth, Abhandl. k. k. geol. Reichs- 
anst. vol. vii. no. 1 (1874), p. 51, pi. iii. fig. 1. — Upper 
Silurian ; Dobrowlany, Galicia. 

Scaphaspis radiata, A. von Alth, ibid. p. 50, pi. ii. fig. 6. — Upper 

Silurian : Zaleszczyki, Galicia. 

Fragments of Pteraspidian shields, not sufficiently complete for 
precise generic determination, are met with in the Lower Devonian 
of Cornwall, and were originally described as fossil sponges by M'Coy, 
under the name of Steganodiciyum cornubicum 1 . Their fish-like 
character was first noted by C. W. Peach 2 , who collected many 
specimens ; they were subsequently assigned to Pteraspis by J. W. 
Salter 3 , and finally named Scaphaspis cornuoic.us byE. Ii. Lankester 
and H. Woodward 4 , and J. E. Lee. Numerous fragments from 
Polperro are preserved in the Lee Collection, and the following is a 
larger specimen : — 

38570 (Invertebrate Register). Small slab with portions of a shield 
showing the external striated surface and the middle can- 
cellated layer ; Fowey. Purchased, 1858. 

According to F. Schmidt (Verhandl. russ.-kais. mineral. Ges. [2] 
vol. viii. 1873, p. 136, pi. v. figs. 9, 10), the so-called Palceoteuthis 
marginalis, E. von Eichwald (Analect. Zool. u. Palaeont. Russlands, 
1871, p. 5, pi. i. fig. 12), from the Petchora, is a doubtful Pteras- 
pidian ; and to the same family may probably be referred the genus 
and species, Tolypelepis undtdatus, C. H. Pander (Foss. Fische Silur. 
Syst. 1856, p. 61, pi. vi. fig. 24), founded upon a fragment of dermal 
plate from the Upper Silurian of Ohhesaar, Isle of Oesel. 

Fragments of dermal plates, perhaps referable to Pteraspidians, 
and consisting of numerous, irregular, closely arranged, narrow 
shining scales, are met with in the Lower Old Red Sandstone of Here- 
fordshire, and named Kallostrakon podura, E. R. Lankester, Fishes 
Old Red Sandst. pt. i. (Pal. Soc. 1870), p. 61, pi. xiii. figs. 20, 21, 
pi. xiv. fig. 6. [Oxford Museum.] The following are specimens of 
this character : — 

45980. Several fragments, varying in coarseness : Lower Old Red 
Sandstone, Bush Pitch, Ledbury. Lightbody Bequest. 

1 F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. viii. (1851), p. 481, and Brit. 
Palreoz. Foss. (1851), pi. ii. a. figs. 1-3. 

2 C. W. Peach, Rep. Brit. Assoc. 1843 (1844), Trans. Sect. p. 56. 

3 J. W. Salter, in Wyatt-Edgell, Geol. Mag. vol. v. (1868), p. 247. 

4 E. R. Lankester and H. Woodward, Geol. Mag. vol. v. (1868), p. 248 ; J. 
E. Lee, ibid. [2] vol. ix. (1882), p. 105. pi. iii. figs. 2, 3, 



176 OSTEOSTRACI. 

P. 2253, P. 2255. Two specimens, one in the form of a thick 
quadrate plate ; Bush Pitch. Egerton Coll. 

P. 4478. Several fragments ; Bush Pitch. Ennislillen Coll. 

P. 5087. Coarse fragment ; Bush Pitch. 

Presented by Jolm Edward Lee, Esq., 1885. 



Order II. OSTEOSTRACI. 

Exoskeleton consisting of calcifications, partly with bone-cor- 
puscles ; each plate comprising three superposed layers, the middle 
layer solid, with a coarse reticulation of large vascular canals. 
Dermal sense-organs leaving no impressions upon the exoskeleton. 
Dorsal shield consisting of one principal piece, sometimes with a 
separate mesial piece or fused body-scales posteriori)- : orbits close 
together. Ventral shield simple, or replaced by polygonal calcifica- 
tions. [Jaws never preserved.] Paired fins absent. 

Synopsis of Families. 

Surface of shield tuberculated ; interorbital 

piece fixed Cephalaspid^ (p. 176). 

Surface of shield finely punctate ; interorbital 

piece loose Tremataspld^: (p. 201). 



Family CEPHALASPIDiE. 

Shield rounded or tapering in front, abruptly truncated behind : 
interorbital piece firmly fixed ; ornamentation consisting of more or 
less numerous tuberculations. [The middle layer of the shield 
sometimes produced postero-laterally into a pair of flexible expan- 
sions (? opercula).] Dorso-lateral squamation consisting of series 
of very deep and narrow, imbricating scales. 

Synopsis of Genera. 

I. Anterior dorsal body-scales not fused into a con- 
tinuous plate. 
Postero-lateral angles of shield produced into 
acute cornua not exceeding the shield in 
length Cephalaspis (p. ] 77). 



CEPHALASPID^. 



177 



Postero-lateral cornua exceeding the shield in 

length Eitkeraspis (p. 193). 

II. Anterior dorsal body-scales fused into a con- 
tinuous plate. 
Cornua divergent ; shield larger than the 

dorsal plate Auchenaspis (p. 195). 

Cornua rudimentary and bordering the dorsal 

plate, which is larger than the shield. . . . Didymaspis (p. 199). 

Genus CEPHALASPIS, Agassiz. 

[Poiss. Foss. vol. ii. pt. i. 1835, p. 135.] 

Syn. Eucephalaspis, E. R. Lankester, Fishes Old Red Sandst. pt. i. 
(Pal. Soc. 1870), p. 43. 
Hemicyclaspis, E. R. Lankester, ibid. p. 43. 
Zenaspis, E. R. Lankester, ibid. p. 43. 

Postero-lateral angles of shield more or less produced into acute 
cornua, not exceeding the shield in length. Body elevated, and 
triangular in transverse section. Flank-scales in three series, the 

Fig. 18. 




Cepkalaspis lyelli 
antorbital 
groove; i. p. 
cells ; p. o. v 
cornu ; p. r., 

upper series of 
series deepest, 
often serrated ; 

PART II. 



Ag. — Outline sketch of shield, restored by Lankester. a. /., 
see; a. p., antorbital prominences; i.g., interorbital ridge or 
, interorbital prominence ; o. r., orbital rim ; m. c, marginal 
,, postorbital valley ; p. a., posterior angle ; p. c, posterior 
posterior ridge ; p. s., posterior spine ; r., rim. 

each side meeting in the mesial line above, the middle 
and the lowermost forming an infero-lateral fringe 
ventral scales apparently small, arranged in V-shaped 



178 OSTEOSTBACI. 

transverse rows equal in number to the series of flank-scales. Scales 
immediately behind the anterior shield not fused together or repre- 
sented by a broad plate. 

The shield of this genus has been described in detail by Huxley 
and Lankester, and the accompanying figures (figs. 18-20) are 
copied from the latter author. Fig. 18 shows the dorsal contour of 
the shield, with its parts indicated by the lettering. The several 
prominences of the hinder border are the lateral cornua {p. c), the 
median spine (p. s.), and the broad median production of the shield, 
with its sharp angles (p. «.). Each orbit has a surrounding rim 
(o. ?'.), extended in front into a small antarbital prominence (a.p*) ; 
and between the eyes is an elongated interorbital prominence (i.p.\ 
evidently hollow, and homologous with the pit in the pineal plate 
of the Antiarcha (see p. 210). Immediately in advance of the latter 
on the under surface of the shield is a small, short, narrow median 
septum. Between the antorbital prominences and this septum is 
the pair of small antorbital fossae (a. /.) exposed only when the 
substance of the shield is removed ; and another great superficial 
fossa (p. o. v.) extends from a ridge or groove (i. g.) joining the hinder 
borders of the orbits to the origin of the median ridge (p. r,) which 

Pig. 19. 




Cephalaspis. — Diagram of inferior aspect of shield, showing 
inferior rim ; after Lankester. 

terminates in the posterior spine. Inexplicable concavities imme- 
diately beneath the cranial roof near the rostrum are named marginal 
cells (m. c), these being more extensively developed round the rim in 
Eukeraspis (fig. 27, p. 194) ; and when the fossil is so preserved as to 
show the contour of some of the originally soft parts, the cast of a 



CEPHALASPID.E. 179 

pair of great rounded lobes, meeting in the middle line, is con- 
spicuous in advance of the orbital region. As shown from beneath 
(fig. 19), the margin of the shield is reflexed inwards to form a 
flattened and ornamented inferior rim, wider behind than in front ; 
and, as proved by transverse sections (fig. 20), the inner border of 




Cephalaspis. — Transverse section of shield, after Lankester. 
i, inferior lamina ; m, margin ; s, superior lamina. 

this rim is continued upwards into a delicate smooth lamina of cal- 
cified tissue (i.), which lies beneath the outer or superior lamina (s.) 
of the shield proper. 



Cephalaspis lyelli, Agassiz. 

1835. Cephalaspis lyellii, L. Agassiz, Poiss. Foss. vol. ii. pt. i. p. 142, 

pi. i. a. fig. 2 (non fig. 1), pi. i. b. figs. 3, 4 {non figs. 1, 2, ? 5). 
1839. Cephalaspis lyellii, R. I. Murchison, Silur. System, p. 589, pi. i, 

figs. 2, 3 {non fig. 1). 
1870. Eucephalaspis lyellii, E. R. Lankester, Fishes Old Red Sandst. 

pt. i. (Pal. Soc), p. 43, pi. viii. fig. 1, pi. xi. figs. 1, 2. 
1870. Eucephalaspis agassizii, E. R. Lankester, ibid, p, 46, pi. ix. figs, 

2, 3, 6, and woodc. fig. 18. 

Type. Head and trunk, wanting fins ; British Museum. 

The type species, of moderate size. Shield sharply rounded or 
obtusely pointed in front; orbits placed nearly midway between 
the anterior and posterior margins ; cornua well developed, broad, 
and acutely pointed. Superficial tuberculations relatively small, 
closely and irregularly arranged. Scaly trunk about two and a half 
times as long as the shield. 

Form. Sf Loc. Lower Old Red Sandstone : Forfarshire, Hereford- 
shire, Monmouthshire, and Worcestershire. 

The English shields originally placed by Agassiz in C. lyelli were 
separated from this species by E. R. Lankester under the name of 
C. agassizi, from the circumstance that " the orbits in the Scotch 
specimens are placed more posteriorly in tne shield, and the cornua 

n2 



180 



OSTEOSTRACI. 



are less produced and less divergent than in the English heads." A 
Glammis specimen mentioned below (No. P. 3234) apparently rend- 
ering this conclusion unjustifiable, we venture to revert to Agassiz's 




Cephalaspis lyclli, kg. — Side view, restored by Lankester. [The opercular fold 
is too distinctly separated from tbe shield, having the appearance of a 
pectoral appendage.] 

original arrangement, and regard the differences as due to accident 
in preservation. 

20087. Type specimen, described and figured by Agassiz (p. 143, 
pi. i. a. fig. 2) and Lankester (p. 44, pi. viii. fig. 1) ; 
Glammis, Forfarshire. Since the original description of 
the specimen by Agassiz, the squamation of the caudal 
region has been more completely extricated from the 
matrix ; and during this process the greater part of the 
opercular fold of each side was accidentally destroyed. 

Presented by Sir Charles Lyell, Bart., 1846. 

P. 3233. Portions of head and trunk of a similar specimen ; Glammis. 

Enniskillen Coll. 

P. 3234. Small shield, much crushed and broken, labelled C. agassizi 
by Mr. William Davies, and agreeing in every respect with 
the definition of this supposed distinct species ; Glammis. 
The portion of shield in advance of the anterior margin of 
the orbits measures 0*015 in length, that behind 0*02. 

Enniskillen Coll. 

42140. Fragments and internal impression of shield ; Cradley, 
Herefordshire. Baugh Coll. 

P. 3235. Small shield, scarcely crushed, but wanting the external 
layers ; Cradley. Enniskillen Coll. 

36052. Portion of a similar specimen ; Cradley or Ludlow. 

Purchased, 1861. 

45945-47, 47 a. Four imperfect shields ; Whitbatch, near Ludlow 

Lightbody Beqiicst. 



CEPHALA.SPIDJE. 181 

P. 672. Flattened imperfect specimen ; Downton, near Ludlow. 

Egerton Coll. 

P. 5048. Partially crushed and broken shield, wanting right cornu ; 
Downton. Presented by John Edward Lee, Esq., 1885. 

P. 4115. Small crushed shield, wanting the external layers and 
showing the orbits placed as far backwards as in the type 
specimen ; Abergavenny. 

Presented by Br. B. M. McCullough, 1883. 

42142. A very small shield, in counterpart, probably young of this 
species ; Heightington. Baugh Coll. 

46568-69, 46877-78. Four very small, much crushed shields, 
doubtfully referable to young of this species ; Cradley. 

Purchased, 1875. 

37388. Middle portion of shield either of this species or of C. salweyi ; 
Heightington. Purchased, 1863. 



Cephalaspis salweyi, Egerton. 

1857. Cephalaspis sahveyi, Sir P. Egerton, Quart. Journ. Geol. Soc 

vol. xiii. p. 283, pi. x. fig. 1. 
1859. Cephalaspis asterolepis, R. Harley, Quart. Journ. Geol. Soc. vol. 

xv. p. 503. 
1859. Cephalaspis salweyi, R. Harley, ibid. p. 504. 
1868. Cephalaspis asterolepis, J. W. Salter, Proc. Woolhope Nat. Field 

Club, p. 240, and frontispiece. 
1870. Zenaspis sahveyi, E. R. Lankester, Fishes Old Red Sandst. pt. i. 

(Pal. Soc), p. 52, pi. xii. figs. 2, 5, 6 (non pi. viii. figs. 2-4), woodc. 

figs. 26, 28 {non fig. 27). 
1881. Cephalaspis asterolepis, H. Woodward, Geol. Mag. [2] vol. viii. 

p. 193, pi. vi. 

Type. Middle portion of shield ; Ludlow Museum. 

The largest known species, the shield sometimes attaining a total 
length of 0*18. Shield sharply rounded in front ; orbits placed 
nearly midway between the anterior and posterior margins ; cornua 
well developed, slender, and acutely pointed. Superficial tubercu- 
lations relatively large, sparsely and irregularly arranged. 

The detached tuberculated plates, doubtfully assigned to this 
species by Lankester, are truly referable to Coccostean fishes (see 
Phlyctoenaspis anglica, p. 296). 

Form, fy Loc. Lower Old Red Sandstone (Cornstones) : Here- 
fordshire, Monmouthshire, and Worcestershire. 



182 OSTEOSTEACI. 

P. 5032. A fine large shield, broken posteriorly, and wanting the 
greater portion of the external tuberculated layer ; Skirrid- 
vawr, Abergavenny. A photograph of this specimen forms 
the frontispiece of the Trans. Woolhope Nat. Field Club, 
1868, and a figure is also given in the Geol. Mag. vol. viii. 
pi. vi. The outline-restoration published by Lankester 
(op. cit. p. 53, woodc. fig. 26) is based upon the same 
fossil, with the cornua next mentioned. The inferior rim 
of the shield has been uncovered since the acquisition of 
the specimen by the Museum. 

Presented by John Edward Lee, Esq., 1885. 

P. 5033. Two imperfect cornua, found in the same quarry as ISTo. 
P. 5032, and employed in the restoration just mentioned ; 
from the cabinet of Dr. D. M. McCullough. 

Presented by John Edward Lee, Esq., 1885. 

41186. Imperfect smaller shield, showing portions of the cornua and 
the external tuberculated layer, noticed by Lankester, op. 
cit. p. 54 ; Cradley. Purchased, 1868. 

42131-32, 42139. Typical shield, somewhat broken, in counterpart, 
and two much crushed and broken specimens, showing 
cornua; Cradley. Baugh Coll. 

42138. Middle portion of shield, showing remains of the external 
tuberculated layer ; locality unknown. Baugh Coll. 

P. 188-191. Three typical specimens, two being partly in counter- 
part; Heightington. Weaver- Jones Coll. 

P. 192. Small crushed^ and broken shield, perhaps referable to young 
of this species ; Heightington. Weaver-Jones Coll. 

33319. Fragment of shield, showing external ornamentation, pro- 
bably referable to young of this species ; Ludlow. 

Purchased, 1858. 



Cephalaspis powriei, Lankester. 

1835. Cephalaspis lyellii, L. Agassiz (pars), Poiss. Foss. vol. ii. pt. i. 

p. 142, pi. i. a. fig. 1, pi. i. b. fig. 1. 
WO. Euccphalaspis powriei, E. R. Lankester, Fishes Old Red Sandst. 

pt. i. (Pal. Soc), p. 47, pi. ix. fig. 5, pi. x. fig. 1, woodc. figs. 19, 

20. 

Type. Well-preserved fish; collection of J. Powrie, Esq., Res- 
wallie. 



CEPHA.LASPID.E. 



183 



Shield sharply rounded in front, broad, and characterized by the 
peculiar curvature of the outline (fig. 22) ; orbits placed nearly mid- 
way between the anterior and posterior margins ; cornua short, 

Fig. 22. 




Cephalaspis powriei, Lank. — Outline of shield, after Lankestef . 

broad, acute, and slightly curved inwards. Superficial tubercula- 
tions relatively small, closely and irregularly arranged. Scaly trunk 
about two and a half times as long as the shield. 

Form, fy Log. Lower Old Red Sandstone i Forfarshire and Ayr- 
shire. 

P. 492. Small well-preserved fish, lateral aspect, figured by Agassiz, 
torn. cit. pi. i. a. fig. 1, as C. lyelli, and noticed by Lan- 
kester, op. cit. p. 48 ; Forfarshire. Egerton Coll. 



50003. Typical shield, in counterpart 



Kinblythemont, Forfarshire. 
Trevelyan Bequest. 



Cephalaspis pagei, Lankester. 

1870. Eucephalaspis pagei, E. R. Lankester, Fishes OldRed Sandst. pt. i. 

(Pal. Soc), p. 49, pi. x. figs. 3, 4, pL xi. fig 1 . 4, woodc. figs. 21, 22. 
1870. Eucephalaspis asper, E. R. Lankester, ibid. p. 50, pi. x. fig. 5 

woodc. fig. 23. [Collection of J. Powrie, Esq., Reswallie.] 

Type. Imperfect fishes; collection of J. Powrie, Esq., Reswallie. 

Shield sharply rounded in front j orbits placed nearly midway 
between the anterior and posterior margins ; cornua short, acute, 
and slightly curved inwards. Superficial ornamentation consisting 



184 



OSTEOSTRACI. 



of relatively large tubercles surrounded by groups of small tubercles ; 
margin of the shield with a close series of well-developed spinelets. 
The outline-restoration of the shield of this species, published by 
Lankester (fig. 23), appears to be too acute anteriorly, while the 
cornua seem to be too straight, long, and narrow. The marginal 

Fig. 23. 





Cephalaspis pagei, Lank. — Outline of shield, and a portion of its superficial 
ornament much magnified (A). After Lankester. 

asperities are shown in all the specimens mentioned below, thus 
confirming Lankester's suspicion that Eucephalaspis asper might be 
only the adult of the present form. 

Form. <$f Loc. Lower Old Eed Sandstone : Forfarshire. 

P. 122-124. Three typical specimens, showing portions of the head 
and trunk, the first two being in counterpart ; Turin Hill, 
Forfar. Purchased, 1880. 

50115. Half of anterior shield, and imperfect lateral aspect of trunk ; 
in micaceous sandstone from Forfarshire. 

Purchased, 1879. 

P. 670. Head and trunk about 0-16 in length ; Turin Hill. The 
anterior portion of the shield exhibits traces of the charac- 
teristic ornament, and the dentate margin is distinct. The 
fine rhomboidal squamation of the heterocercal tail is well 
preserved ; and the dorsal and caudal fins occur as granu- 
lated membranous expansions. Egerton Coll. 

P. 125. Imperfect head and trunk of a large individual, in counter- 
part ; Turin Hill. This specimen precisely resembles the 
typical C. asper. Purchased, 1880. 



CEPHALASPJD^. 185 

Cephalaspis murchisoni, Egerton. 
[Plate IX. fig. 6 ; Plate X. figs. 1-4.] 

1857. Cephalaspis murchisonii, Sir P. Egerton, Quart, Journ. Geol. Soc. 

vol. xiii. p. 284, pi. ix. fig. 1. 
1857. Cephalaspis ornatus, Sir P. Egerton, ibid. p. 285, pi. ix. figs. 2, 3. 

[Imperfect shield ; British Museum.] 
1870. Hemicyclaspis murchisoni, E. K. Lankester, Fishes Old Red 

Sandst. pt. i. (Pal. Soc), p. 51, pi. viii. fig. 6, pi. ix. fig. 1, pi. xiL 

figs. 3, 4. 

Type. Shield ; unknown. 

The type species of the subgenus Hemicyclaspis, of moderate size. 
Shield sharply rounded in front; orbits placed nearly midway 
between the anterior and posterior margins ; cornua rudimentary. 
Superficial ornamentation consisting of widely spaced, regularly 
arranged, large tubercles, with intervening small tubercles. Scaly 
trunk about three times as long as the shield. 

Form. Sf Loc. Ludlow Tilestones and Lower Old Red Sandstone 
Passage Beds : Herefordshire. 

The specimens presented by George H. Piper, Esq., recorded below 
and shown in the accompanying Plates, make known the exoskeleton 
of this species almost completely, and add important items to our 
knowledge of the morphology of the Cephalaspidians in general. A 
restoration is attempted in the woodcut (fig. 24), and the following 
are detailed notes on the collection. 

Fig. 24. 




Cephalaspis murchisoni, Egert. — Side view, restored from specimens discovere 
by George H. Piper, Esq. [Nos. P. 6023, &c.J 

The precise form and proportions of the anterior shield have 
already been determined by Lankester (fig. 25), and the fossils under 
discussion are quite similar to those previously studied. The absence 
of posteriorly prolonged cornua is distinctly shown ; there is the 
well-defined high " posterior ridge "behind the " postorbital valley,'* 
and the usual three layers entering into the constitution of the shiel 
are readily distinguishable. There is also no trace of sensory 
canals. 



186 



OSTEOSTRACI. 



The superficial ornamentation is not very satisfactorily exhibited, 
but one specimen (P. 6109) shows an impression of the external 
surface, represented of four times the natural size in PL X. fig. 3 ; 
and this evidently conforms to the type described and figured by 
Lankester in the fossils from the Ludlow Tilestones, named 
C. ornatus by lilgerton (fig. 25, A). Lankester's determination of the 
identity of the latter form with C. murchisoni is thus confirmed. 

A novel point of much general interest is elucidated by the middle 



Fig. 25. 




Cephalaspis murckisoni, Eg. — Outline of shield, and portion of ornament much 
magnified (A). After Lankester. 

layer of the shield, which is well preserved in several specimens. 
As already demonstrated by Huxley and Lankester, this layer is 
divided into a number of distinct polygonal areas, by a system of 
reticulate, branching vascular canals ; and the present specimens 
prove distinctly that it extends backwards as a pair of postero- 
lateral " flaps " beyond the rest of the shield. Such an extension 
is shown in PL X. fig. 1, a?, in the individuals numbered I. and II. 
in the large group (P. 6023) mentioned below. The outer layer is 
broken away, so that direct continuity can be observed between the 
appendage and the middle layer, and the precise shape of most of 
the areas or plates is distinguishable. As far as the posterior ex- 
tremity of the shield the outer lateral margin is apparently undivided 
by vascular channels, and the areas within are approximately as 
long as broad ; but in the appendage the outer border is divided into 



CEPHAXA.SPID.E. 187 

oblong portions, the areas immediately within this are at least as 
long as broad, while those forming the greater part of the " flap " are 
considerably broader than long, and are suggestive of a certain 
amount of flexibility in the original structure. The precise outline 
of the extension is not determinable, but it evidently tapers pos- 
teriorly, and its extreme length is nearly equal to half the length of 
the shield. 

Appendages of the character just described have already been 
noticed by Powrie and Lankester, and, in the absence of satisfactory 
evidence as to their connections, they have naturally been regarded 
as pectoral fins. It now appears, however, that the structures are 
merely a portion of the shield itself, divested of the outer and inner 
layers to ensure flexibility. The arrangement and peculiarities of 
the compound plates have, indeed, suggested to Prof. Lankester that 
these appendages " may have had other functions than that of mere 
locomotion ;" and he adds, as not improbable, " that they may have 
been efficient in causing currents of water to pass to the branchial 
organs covered in by the great head-shield (whose outlets are indi- 
cated by the lateral perforation in the shield of Pteraspis), and have 
thus aided respiration as well as locomotion, as is observed in the 
fry of Teleostean fishes at the present day with regard to the pectoral 
fin." Some connection with the gills has thus already been suspected, 
and it now seems most probable that the appendages in question 
actually correspond to a pair of opercula, and may henceforth be 
designated as such. 

The inferior surface of the head is only shown in part by one fossil, 
and the structures are not sufficiently complete to give any clue as 
to the characters of the mouth. At least posteriorly, the skin is 
supported by thin and delicate polygonal plates, closely fitted to- 
gether (see PI. X. fig. 2). 

As in the more typical members of the genus Cep7ialaspis, the por- 
tion of trunk behind the shield is trihedral in form, gradually tapering 
towards the caudal extremity, and having a segmented appearance, 
owing to the shape and arrangement of the scutes. As shown dis- 
tinctly by one specimen (PI. X. fig. 4) and less distinctly by others, 
the inferior surface is formed by a single paired series of elongated 
scutes (v.), each broadest at its outer extremity and gradually nar- 
rowing while directed forwards mesially. A series of small scutes 
corresponding in number, and forming a kind of fringe, is arranged 
along the inferior lateral angle (I.) of both sides. Each of these is 
only connected with the one in front and behind at its base, and the 
outer free extremity is directed backwards, while the anterior 
margin is gently rounded and serrated. Again of equal number, and 
having bevelled ends articulating with the inferior marginals just 



183 OSTEOSTRACI. 

described, is the series of vertically elongated lateral scutes (PI. X. 
fig. 1, Xo. 1, and fig. 4, d.l.). All these are more or less upright 
in position, except towards their superior extremities, where they 
not only become sharply bent forwards, but are also considerably 
narrowed. There is no modification immediately behind the shield 
suggesting the presence of a splint system in connection with a pec- 
toral arch, and all the plates, to the number of 46, are of about equal 
width as far as the position of the dorsal fin ; more posteriorly, the 
lateral scutes are relatively broader and bent forwards at both ex- 
tremities. Above (as shown especially in PL X. fig. 1, No. 1), the 
crest of the trunk is formed by a single median series of large scutes, 
TV-shaped in transverse section, connected and on a level with the 
*' posterior ridge " of the shield. For almost the whole of the dis- 
tance between the shield and the dorsal fin, this ridge is very high 
and acute, the angle between the two lateral halves of the scutes 
being extremely small ; more posteriorly, the ridge seems to sink, 
not being angulated, but gently arched from side to side. While 
the lateral and ventral scutes are distinctly imbricating, many of 
these ridge-scutes seem to afford very little provision for flexibility, 
three or four, indeed, being sometimes fused together in front of 
the dorsal fin ; they are broader than the lateral scutes, each corre- 
sponding to one and a half or two of these, but more posteriorly 
their width is exceeded by that of the laterals. The extremity of 
the tail is unfortunately too imperfect to show the precise characters 
of its dermal armour. 

No tuberculations are to observed upon the scutes, the external 
surface, when preserved, apparently only exhibiting the extremely 
fine, short striae, which are also seen upon the anterior shield be- 
tween its tubercular ornament. Most of these striae are in the 
direction of the long axis of the trunk, and, when highly magnified, 
they have a beaded appearance. The free posterior border of all the 
scutes is destitute of serrations. 

On comparing the arrangement of the dermal armour thus 
described with that already made known by Lankester in the " sub- 
genus Emejplialaspis" it will be found to agree in most essential 
particulars. Many of the points of difference are very possibly to be 
accounted for by imperfections in the original fossils, the only 
marked contrast being found in the ventral scutes, which are directed 
forwards instead of backwards, as determined in the type species 
(Lankester, pi. xi. fig. 2). It is also considered probable that in the 
latter the ventral pair of scutes is divided by sutures into four sym- 
metrical pairs ; that the upper median scutes are paired, not azygous ; 
and that immediately behind the dorsal fin arrangements change, 



CEPHALASPIDJE. 1 89 

the encircling scutes being relatively smaller and more numerous. 
In some Forfarshire specimens, moreover, the superficial ornamen- 
tation is in the form of distinct tubercles. 

The new specimens obviously confirm Lankester's suspicion, that 
there is no " nuchal " plate behind the anterior shield, as was con- 
sidered possible by Egerton. 

Numerous sections of the trunk in various directions show no 
traces of a hard internal skeleton, and thus are also confirmatory of 
previous conclusions on the subject, based upon the study of exam- 
ples of the typical species. 

The only fin preserved in Mr. Piper's fossils is the dorsal, which 
seems to be incompletely shown in No. P. 6023. There are no well- 
defined fin-rays, the supporting structures being small, oblong, cal- 
cified plates, closely fitted together, and placed end to end in vertical 
parallel series. The arrangement is very suggestive of that of the 
fragmentary fossils described by Lankester from the Bush Pitch Beds 
under the name of KallostraTcon podura (see p. 175). 

45944. Type specimen of Cephalaspis ornata, Egerton ; Tilestones, 
Ludlow. Lightbody Bequest. 

P. 673, P. 676. Two portions of shields ; Auchenaspi s-Grits (Pas- 
sage Beds), Ledbury, Herefordshire. Egerton Coll. 

P. 3238-39. Four similar specimens, one being in counterpart; 
Auchenaspis-Grits, Ledbury. Ennishillen Coll. 

P. 6023. Block of sandstone with more or less fragmentary remains 
of about twelve individuals, shown, of the natural size, in 
PI. X. fig. 1 ; red sandstone in Passage Beds, Ledbury. 

Presented by George H. Piper, Esq., 1889. 

P. 5317. Crushed portions of the shield and scaly trunk of two 
associated individuals, one displaying the operculum ; 
red sandstone, Ledbury. 

Presented by George H. Piper, Esq., 1887. 

P. 6260. Imperfect shield and anterior portion of the caudal region, 
the latter fractured and showing the ventral scales (PI. X. 
fig. 4, v.) ; red sandstone, Ledbury. 

Presented by George H. Piper, Esq., 1890. 

P. 6261. Imperfect shield and anterior portion of the caudal region, 
showing well-preserved dorsal ridge-scales ; red sandstone, 
Ledbury. Presented by George H. Piper, Esq., 1890. 

P. 6108. Portion of the anterior shield broken in such a manner as 
to expose the irregular polygonal dermal calcifications 



190 OSTEOSTRACI. 

of the ventral aspect of the body between the inferior rim, 
shown, of the natural size, in PI. X. tig. 2; red sandstone, 
Ledbury. Presented by Georye H. Piper, Esq., 1889. 

P. 5319-20. Impressions of two shields showing absence of cornua, 
the first displaying the inner aspect, the second the outer ; 
red sandstone, Ledbury. 

Presented by George H. Piper, Esq., 1887. 

P. 6109. Well-preserved impression of a portion of shield, outer 
aspect, showing the external ornament (PI. X. fig. 3) ; 
red sandstone, Ledbury. 

Presented by Georye H. Piper, Esq., 1889. 

P 5318. Flank-scales of greater portion of trunk, in natural order ; 
red sandstone, Ledbury. 

Presented by George H. Piper, Esq., 1889. 

P. 6111. Portion of inferior rim of shield, of the form doubtfully, 

though with much probability, assigned to this species by 

Lankester (op. cit. pi. ix. fig. 4) : red sandstone ; Ledbury. 

The fossil is shown, of the natural size, in PI. IX. fig. 6. 

Presented by George H. Piper, Esq., 1889. 



Cephalaspis lightbodii, Lankester. 

1870. Cephalaspis lightbodii, E. R. Lankester, Fishes Old Red Sandst. 
pt. i. (Pal. Soc), p. 55, pi. xiii. fig. 19. 

Type. Inferior rim oi shield ; British Museum. 

A provisionally determined large species, known only by the type 
specimen and unsatisfactory fragments. Rim of shield ornamented 
with closely arranged, conical or pyramidal tubercles, having their 
apices sometimes recurved. 

Form. Sf Loc. Ludlow Tilestones ; Ludlow. 

45940. Type specimen. LigJitbody Bequest. 



Cephalaspis campbelltonensis, Whiteaves. 
[Plate IX. fig. 5.] 

1881. Cephalaspis campbelltonensis, J. F.Wkiteave?, Canadian Natural- 
ist, n. s. vol. x. p. 98. 

1889. Cephalaspis campbelltonensis, J. F. "Whiteaves, Trans. Roy. Soc. 
Ganada ; vol. vi. sect. iv. p. 92, pi. x. fig. 2. 



CEPHALASPID^E. 



191 



1890. Cephalaspis campbelltoivnensis, R. H. Traquair, Geol. Mag. [3] 

vol. vii. p. 21. 
1890. Cephalaspis whiteavesi, R. H. Traquair, ibid. p. 21. [Shield; 

Edinburgh Museum.] 

Type. Shield ; Geological Survey Museum, Ottawa. 

A species of large size, the shield with cornua attaining a length 
of not less than 0*18. Shield produced anteriorly into a short, nar- 
row, sharply rounded rostrum ; orbits placed nearly midway between 
the anterior and posterior margins ; cornua long, broad at the base, 
acutely pointed, slightly inflected, and finely denticulated on the 
inner margin. Cornua ornamented with fine reticulating rugse ; 
[ornament of shield unknown]. 

The peculiar rostrum of this species is solid, much resembling 
that of Pteraspis. It is well shown in the type specimen, though 
accidentally omitted in the original description and restored outline. 
As remarked by Whiteaves, the relative proportions of the orbits 
and interorbital space vary considerably — the result, probably, of 
accidental crushing. 

Form. <$f Loc. Lower Devonian ; Campbellton, New Brunswick. 

P. 5477. Slab of shaly rock with remains of four shields, associated 
with fragments of Phlyctcenaspis and plants. 

Purchased, 1888. 

P. 5970. Remains of a very large shield, with orbits and one cornu. 

Purchased, 1889. 

P. 5478. Crushed shield with cornua. Purchased, 1888. 

P. 5479. Anterior two-thirds of shield, with rostrum, shown, of 
two-thirds the natural size, in PI. IX. fig. 5. 

Purchased, 1888. 

P. 4576, Similar specimen, with rostrum relatively shorter and more 
acutely pointed. Purchased, 1888. 

P. 5971. Fragment with rostrum. Purchased, 1889. 

P. 5480. Imperfect impression of inner aspect of shield, with the 
inferior rim. Purchased, 1888. 

P. 5971 a. Fragment showing part of the hinder border of the 
shield. Purchased, 1889. 

P. 5974. Fragmentary squamation, probably of this species. The 
scales are ornamented with very fine tubercles often fused 
in series. Purchased, 1889. 



192 



OSTEOSTRACI. 



Cephalaspis dawsoni, Lankester. 

1S70. Cephalaspis daiosoni, E. R. Lankester, Geol. Mag. vol. vii. p. 397, 
woodcut. 

Type. Head and trunk • Redpath Museum, Montreal. 

A small species, known only by the type specimen. Shield much 
broader than long, with prominent cornua ; surface very finely tu- 
berculated. Scaly trunk remarkably small and slender in proportion 
to the shield ; infero-lateral scales with serrated free border. 

Form. Sf Loc. Lower Devonian : Gaspe, Canada. 

Not represented in the Collection. 

Fig. 26. 







Cephalaspis dawsoni, Lank.— Dorsal aspect (1), nat. size, and a portion of the 
tubercular ornament (2), much magnified, after Lankester. Lower Devo- 
nian, Canada. [Redpath Museum, Montreal.] 



Cephalaspis laticeps, Traquair. 

1890. Cephalaspis laticeps, R. H. Traquair, Geol. Mag. [3] vol. vii, 
p. 16. 

Type. Shield with remains of squamation ; Edinburgh Museum. 



CRPHALA8PID/E. 193 

Shield proportionately rather broad; cornua short, orbits rather 
close together, oval, large ; tesselated divisions of middle layer very 
small ; external surface ornamented by small, smooth, polished and 
rounded tubercles, moderately close in position. (Traquair.) 

The shield in the type specimen measures 0*034 in length and 
0-069 in breadth. 

Form. Sf Loc. Upper Devonian : Scaumenac Bay, P. Q., Canada. 

Not represented in the Collection. 

A fragment apparently of the shield of Cephalaspis, from the 
Lower Devonian of Dickson Bay, Spitzbergen, is recorded by E. R. 
Lankester, Kongl. Svenska Yetensk.- Akad. Handl. vol. xx. no. 9 
(1884), p. 5, pi. i. figs. 4, 5. [Royal State Museum, Stockholm.] 

A fragment from the Devonian of Cornwall named Steganodictyum 
carteri by F. M'Coy (Ann. Mag. Xat. Hist. [2] vol. viii. 1851, p. 482, 
and Brit. Palseoz. Foss. 1855, pi. ii. a. fig. 4) is also recorded as 
Cephalaspis (?) carteri by E. R. Lankester, Fishes Old Bed Sandst. 
pt. i. (Pal. Soc. 1870), p. 42. 

Genus EUKERASPIS, Lankester. 

[Fishes Old Red Sandst. pt. i. (Pal. Soc. 1870), p. 56.] 

Syn. Sclerodus, L. Agassiz, in Murchison's Silur. Syst. 1839, p. 606 
(inappropriate). 
Plectrodus, L. Agassiz, ibid. p. 606 (inappropriate). 

Postero-lateral angles of shield produced into enormous cornua, 
exceeding the shield in length, and provided on the outer margin 
with a series of prominent denticulations ; a marginal row of about 
six large quadrate cavities on each side between the two laminse of 
the shield. 

Eukeraspis is regarded by Lankester as a subgenus of Auchenaspis, 
on the assumption that a second dorsal shield was originally present 
behind the one already known. The detached cornua were de- 
scribed by Agassiz as jaws of fishes under the names of Sclerodus 
and Plectrodus, and seem to have been first correctly interpreted by 
Harley 1 . 

Eukeraspis pustulifera (Agassiz). 

1839. Sclerodus pustuliferus, L. Agassiz, in Murchison's Silur. Syst. 

pp. 606, 704, pi. iv. figs. 27-32, 60-62. 
1839. Plectrodus mirabilis and P. pleiopristis, L. Agassiz, ibid. pp. 606, 

704, pi. iv. figs. 14-26. 

1 J. Harley, in Murchison's Siluria, ed. 4 (18t>7), expl. to pi. xxxv. 
PART II. O 



L94 



0STE0STKAC7. 



1854. P/ectrodus (Sclerotitis) pustuliferus, E. I. Murchison, Siluria, 

pi. xxxv. figs. 9-12. 
1854. Plectrodus mirabilis, R. I. Murchison, ibid. pi. xxxv. figs. 3-8. 
1870. Euheraspis pustuliferus, E. R. Lankester, Fishes Old Red 
Sandst. pt. i. (Pal. Soc), p. 58, pi. xiii. figs. 9-14. 

Type. Portions of corrma. 

The type species, of small size, the maximum total length of the 
shield with its cornua being about 0*05. Cornua flattened from 

Fig. 27. 





Enkeraspis pustulifera (Ag.). — Outline of shield, after Lankester. op., ant- 
orbital prominence; mc, marginal cells; ip., interorbital prominence; 
pv., postorbital valley. A. Portion of ornament, much magnified. 



above downwards, twice as long as the body of the shield ; the ex- 
ternal denticulatious stout, smooth, and irregularly spaced, with 
or without feeble intermediate points ; superficial tuberculations 
numerous, small, rounded, and closely arranged. 

Form. § Loc. Upper Ludlow and Downton Sandstone : Hereford- 
shire. 

45949, a, b. Impression of cornu, and two imperfect shields, figured 
by Lankester, op. cit. pi. xiii. figs. 11, 13, 14; Downton 
Sandstone, Ludford Lane, Ludlow. Lightbody Bequest. 

45970, 45973. Cornu and two fragments : Ludford Lane. 

Lightbody Bequest. 



GEPHAJiAarmzE. 196 

45970 a. Two cornua from " Troclms bed," Downton Bridge. 

Lightbody Bequest. 

P. 3247. Cornu from Bone-bed in Upper Ludlow, near Ludlow 

Enniskillen Coll. 
P. 5844. Cornu; Downton Sandstone, Kington. 

Presented by John Edward Lee, Esq., 1885. 

The following specimen is doubtfully assigned to an unknown 
species of Eukeraspis : — 

45969. A long, narrow fragment of smooth fibrous bone, denticu- 
lated on the thin long margin, and noticed under the 
name of Plectrodus by Egerton, Quart. Journ. Geol. Soc. 
vol. xiii. (1857), p. 288, pi. x. fig. 2; Downton Sand- 
stone, opposite the Paper-Mill, near Ludlow. The den- 
ticles are slender, pointed, and longitudinally grooved, and 
are arranged in two series, the inner being largest and 
widely spaced. The bone has more completely the aspect 
of a jaw than the cornua of the typical Eukeraspis. 

Lightbody Bequest. 

A fragment of denticulated bone from a Lower Palaeozoic Boulder, 
found near Danzig, is also described as Plectrodus mirabilis (?) by 
F. Roemer, Palseont. Abhandl. vol. ii. (1885), p. 359, pi. xxxi. 
fig. 26. [University of Breslau.] 

Genus AUCHENASPIS, Egerton. 

[Quart. Journ. Geol. Soc. vol. xiii. 1857, p. 286.] 

Syn. Thyestes, E. von Eichwald, Bull. Soc. Imp. Nat. Moscou, 1854, 
pt. i. p. 108 (inaccurate definition). 

Postero-lateral angles of shield more or less produced into acute 
cornua, not exceeding the shield in length. Body depressed, ovoid 
in transverse section ; three or four series of dorso-lateral scales 
fused into a continuous plate immediately behind the shield. 
Tuberculations in part very large. 

Having had the privilege of examining some of the original ex- 
amples of Thyestes described by Eichwald, Pander, and Schmidt, in 
St. Petersburg, the present writer finds the orbits as distinctly 
marked in the Oesel fossils as in the typical shields of Auchenaspis 
from Herefordshire. Moreover, some of the specimens of Auchen- 
aspis egertoni discovered by Mr. Piper in the Ledbury Passage Beds 
exhibit traces of the very large tuberculations and the transverse 

o2 



1 96 



OvSTEOSTRACI. 



banding of the posterior shield described as characteristic of Thy- 
estes. That the two generic names pertain to a single type thus 
appears certain, and we prefer that of Auchenaspis as being most 
accurately and recognizably defined. 

Auchenaspis salteri, Egerton. 

1857. Auchenaspis salteri, Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. xiii. p. 286, pi. ix. figs. 4, 5. 
1870. Auchenaspis salteri, E. E. Lankester, Fishes Old Eed Sandst. 

pt. i. (Pal. Soc), p. 56, pi. xiii. figs. 7, 8. 

Type. Imperfect shield ; British Museum. 

The type species, of very small size, the two shields having a 
maximum antero-posterior measurement of about 0*011. Orbits 



Fie. 28. 



Fig. 29. 





Fig. 28. Auchenaspis salteri, Egert. — Outline of shield, after Lankester. 
Fig. 29. Auchenaspis egertoni, Lank. — Outline of shield, after Lankester. 

placed in advance of the middle point of the anterior shield ; cornua 
not much produced and scarcely divergent ; [ornament unknown]. 
Form, fy Loc. Upper Ludlow Tilestones ■ Ludlow. 



45952. Type specimen. 

P. 674. Internal impression of shield. 



Lighibody Bequest. 
Egerton Coll. 



Auchenaspis egertoni, Lankester. 

[Plate X. figs. 5, 6.] 

1870. Auchenaspis egertoni, E. R. Lankester, Fishes Old Red Sandst. 
pt. i. (Pal. Soc), p. 57, pi. xiii. figs. 3-5. 

Type. Shields ; Oxford Museum. 

A species somewhat larger than the type, the two shields having 
a maximum antero-posterior measurement of about 0*02. Orbits 
situated in the middle of the anterior shield ; cornua divergent, 
produced to extend at least as far as the hinder margin of the pos- 



CEPHALASPID.E. 1U7 

terior shield ; relatively large superficial tuberculations arranged in 
two or three symmetrical pairs of antero-posteriorly directed lines. 
Scaly trunk somewhat longer than the two shields. 

Form. $ hoc. Lower Old Red Sandstone Passage Beds : Ledbury, 
Herefordshire. 

[P. 6023.] Small individual, dorsal aspect, mingled with a large 
group of Cephalaspis murchisoni (PL X. fig. 1), and 
shown, of the natural size, in PI. X. fig. 5. The scaly 
trunk is somewhat longer than the shield with its pos- 
terior plate, and the scutes are apparently arranged as in 
Cephalaspis, the only modifications relating to the more 
depressed form of the body. In transverse section the 
trunk is almost a depressed oval ; the dorsal ridge is thus 
less sharp, owing to the wider angle between the two 
halves of the ridge-scutes, while the lateral scutes are 
strongly arched in the direction of their long axis. 

. Presented by George H. Piper, Esq., 1889. 

P. 5316. Similar specimen more imperfectly preserved, partly 
shown in counterpart; from red sandstone in Passage 
Beds. Immediately behind the posterior dorsal shield, 
the median series of flattened A-shaped dorsal ridge scales 
occurs, and there are remains also of some of the vertically- 
elongated flank scales. A small portion of the ventral 
aspect of the fish is exposed, displaying beneath part of 
the shield a number of irregular polygonal calcified 
tesserae, and also suggestive indications of a broad conti- 
nuous ventral plate, opposed to the hinder portion of the 
dorsal shield. Presented by George H. Piper, Esq., 1887. 

P. 5315. Imperfect shield in similar matrix. 

Presented by George H. Piper, Esq., 1887. 

P. 6112. Imperfect shield in similar matrix, displaying portions of 
the antero-posterior series of large tuberculations, and 
shown, of the natural size, in PL X. fig. 6. 

Presented by George H. Piper, Esq., 1889. 

36187-90. Four typical shields, from the " Auchenasjris-Grit." 

Purchased, 1861. 

46954. Two associated shields in similar matrix. Purchased, 1876. 

P. 675. Six shields in similar matrix. Egerton Coll. 

P. 3237. Four similar specimens, two being associated. 

EnnisJciUen Coll. 



198 OSTEOSTRACI. 

P. 5083. Three similar specimens. 

Presented by John Edward Lee, Esq., 18S5. 

P. 5371. Pour similar specimens, one showing traces of the large 
superficial tuberculations. Purchased, 1887. 

P. 6113 a. Similar specimen, showing traces of the large superficial 
tuberculations. Presented by George H. Piper, Esq., 1889. 

P. 5314, P. 6113. Two imperfect shields in mudstone, the second 
showing the transverse banding of the posterior plate. 

Presented by George H. Piper, Esq., 1887-89. 

Auchenaspis verrucosa (Eichwald). 

1854. Thyestes verrucosus, E. von Eichwald, Bull. Soc. Imp. Nat. 

Moscou, pt. i. p. 108, pi. ii. fig. 1. 
1856. Cephalaspis verrucosus, C. H. Pander, Foss. Fische Silur. Syst. 

p. 47, pi. iv. figs. 1,3-7. 
1858. Cephalaspis verrucosus, T. H. Huxley, Quart. Journ. Geol. Soc. 

vol. xiv. p. 269. 
1860. Thyestes verrucosus, E. von Eichwald, Leth. Rossica, vol. i. pt. ii. 

p. 1532. 
1866. Thyestes verrucosus, F. Schmidt, Verhandl. russ.-kais. mineral. 

Ges. St. Petersburg, [2] vol. i. p. 225, pi. iv. figs. 1-12. 

Type. Shield ; University of St. Petersburg. 

The type species of Thyestes. Shield resembling that of A. eger- 
toni in form and proportions ; external margin of anterior plate 
with a regular close series of blunt tuberculations ; transverse sulci 
between the components of the posterior plate prominent. Super- 
ficial ornament consisting of three symmetrically arranged, paired, 
longitudinal series of large tubercles, extending the whole length of 
the shield, with irregularly scattered small tubercles between ; the 
longitudinal median ridge of the posterior plate apparently consist- 
ing of imperfectly-fused large tubercles. 

As remarked by Huxley and Schmidt, the supposed jaws de- 
scribed by Pander are fragments of the tuberculated rim cf the 
anterior shield. The orbits have not been indicated in published 
figures and descriptions, but they are as distinctly shown in some of 
the original specimens as in the typical Auchenaspis from Hereford- 
shire. The markings determined as orbits by Schmidt are too far 
forwards and too small, and the supposed median longitudinally- 
elongated vacuity is the now well-known large superficial fossa. 

Form. <y Loc. Upper Silurian : Isle of Oesel, Baltic Sea. 

Not represented in the Collection. 



CEPHALASPID2E. L99 

Genus DIDYMASPIS, Lankester. 

[Geol. Mag. vol. iv. 1807, p. 152.] 

An imperfectly known genus, with two anterior dorsal shields, 
differing only from those of Auchenaspis in the absence of promi- 
nent cornna, and in the relatively greater size of the hinder shield. 
A large ventral shield is opposed to the latter. 

Didymaspis grindrodi, Lankester. 
[Plate IX. figs. 7, 8.] 

1807. Didymaspis grindrodi, E. R. Lankester, Geol. Mag. vol. iv. 

p. 153, pi. viii. figs. 4-7. 
1870. Didymaspis grindrodi, E. R. Lankester, Fishes Old Red Sandst. 

pt. i. (Pal. Soc), p. 59, pi. xiii. figs. 1, 2. 

Type. Shield ; Oxford Museum. 

The type species, of small size, the maximum antero-posterior 
measurement of the two shields being about 0-025, and their maxi- 
mum breadth 0*018. The two dorsal shields firmly united, the 
anterior somewhat smaller than the posterior, and the latter taper- 
ing, though abruptly truncated behind ; the line of junction between 
the two shields describing a double curve, the produced lateral 

Fig. 30. 




Didymaspis grindrodi, Lank. — Outline of shield, after Lankester. 

angles of the anterior portion embracing the posterior portion, but 
not diverging from it, while in the median line the anterior shield 
is produced into the posterior to a small extent. Superficial orna- 
mentation consisting of irregularly arranged fine tubercles ; a faint 
median keel in the hinder half of the posterior shield. 

Form. fy Loc. Lower Old Red Sandstone : Ledbury, Hereford- 
shire. 



200 08TEOSTRA.CI. 

P. 5043. A typical specimen showing an impression of the inner 
aspect of the dorsal shield, with a loose portion of matrix 
lying between the hinder plate of this shield and an 
equally large, opposed ventral plate, of which the sub- 
stance is preserved; Bush Pitch, near Ledbury. The 
portion of matrix representing the space occupied by the 
soft parts of the animal is very thin, as shown in the 
transverse section, PI. IX. fig. la. The ventral plate 
(PI. IX. fig. 7), as seen from the visceral aspect, is flat- 
tened, marked with the numerous openings of apparently 
vascular canals, and is not seen to extend beneath the 
anterior shield. 

Presented by John Edward Lee, Esq., 1885. 

P. 5313. Dorsal aspect of shield, showing portions of the external 
tuberculated layer ; Bush Pitch. The specimen is shown, 
of the natural size, in PI. IX. fig. 8, and a portion of the 
ornament enlarged four times in fig. 8 a. The posterior 
plate is gently rounded from side to side, with only faint 
indications of a longitudinal median keel in the hinder 
half ; and the superficial ornamentation consists of nume- 
rous rounded tubercles, closely, but irregularly arranged. 
Presented by George H. Piper, Esq., 1887. 

A fossil of very doubtful relationships, sometimes assigned to the 
family of Cephalaspidae, is described as follows : — 

Menaspis armata, T. Ewald, Bericht k. preuss. Akad. Wiss. 1848, 
p. 33; H. B. Geinitz, Dyas (1861), p. 21.— Upper Per- 
mian (Zechstein) ; Lonau, Harz Mts. [Collection of 
Dr. Ewald, Berlin.] 

Another supposed ally of the Cephalaspidae is described thus : — 
Cephalopterus pagei, J. Powrie, Trans. Edinb. Geol. Soc. vol. i. 
(1870), p. 298, pi. xiv. fig. 16.— Lower Old Bed Sand- 
stone : Turin Hill, Eorfar. [Collection of James Powrie, 
Esq., Eeswallie, and Dundee Museum.] 



TRHMATASPID.E. 



201 



Family TREMATASPID^E. 

Shield rounded or tapering in front, abruptly truncated behind ; 
interorbital piece not fixed ; external surface, covered with punctate 
ganoinc, the punctations often arranged in reticulating lines; super- 
ficial tuberculations almost or entirely absent. 

Genus TREMATASPIS, Schmidt. 

[Verhandl. russ.-kais. mineral. Ges. St. Petersburg, [2] vol. i. 
I860, p. 233.] 

Syn. (?) Stiymolepis, C. H. Pander, Foss. Fische Silur. Syst. 1856, p. 53. 
Odontotodus, C. H. Pander, ibid. p. 75 (inappropriate). 

Shield simple, the postero-lateral angles not produced into cornua ; 
a continuous ventral plate opposed to its posterior two-thirds. A 
circular depression immediately in advance of the orbital opening, 
with an antero-posteriorly elongated cleft in the centre; an oval 
fossa or cleft behind the orbital opening. 

In the ordinary state of preservation of the shield it is difficult to 
distinguish broken eminences and depressions from vacuities ; and 
it is quite possible that the post-orbital and lateral openings 




Fig. 32. 




Fig. 31. Tremataspis schrenki (Pander). — Outline of shield, dorsal aspect, 

after F. Schmidt. 
Fig. 32. Tremataspis schrenki (Pander)- — Outline of anterior portion of shield, 

ventral aspect, after F. Schmidt, 

described by Schmidt are due to features of this kind accidentally 
removed. The appearances are distinct in the original specimens, 
and, whether they be due to vacuities, eminences, or depressions, 
they are at present not readily interpreted. 



202 



AXIIAKCHA. 



Tremataspis schrenki (Pander). 



L866. Cephalaspis sehrenkii, C. H. Pander, Foss. Fische Silur. Syst. 
p. 47, pi. iv. fig. 2. 

(?) 1856. Stigmolepis owenii, C. II. Pander, ibid. p. 53, pi. v. fig. 7. 
1 B56. Odontotodus rootsikuellensis, C.H. Pander, ibid. p. 75, pi. vi. fig.21. 
I860. Tremataspis schrenkii, F. Schmidt, Verhandl. russ.-kais. mineral. 
Ges. 'St. Petersburg, [2] vol. i. p. 233, pis. v., vi. 

Ttype. Fragment of shield ; School of Mines, St. Petersburg. 

Shield depressed, gently rounded, longer than broad; anterior 
margin obtusely rounded ; lateral margin, and the anterior margin 
of the ventral shield, coarsely crenulated ; posterior margin slightly 
excavated. Orbital opening situated at about one-fifth of the total 
length of the shield from its anterior extremity ; postorbital " va- 
cuity " antero-posteriorly elongated, pear-shaped ; a faint median 
longitudinal ridge towards the hinder end of the shield. 

Form. 4' Loc. Upper Silurian : Kootsikiille, Isle of Oesel. 

Xot represented in the Collection. 

The so-called Chordate genus and species, Mycterops ordinatus, 
E. D. Cope, Amer. Naturalist, 1886, p. 1029, woodcut, from the 
Coal-measures of Pennsylvania, is founded upon an imperfect shield 
of an Eurypterid in the collection of Prof. E. D. Cope, Philadelphia 
(A. S. Woodward, Geol. Mag. [3] vol. vii. 1890, p. 395). 



Order III. ANTIARCHA. 

Exoskeleton consisting of calcifications with bone-corpuscles, and 
invested with a more or less continuous superficial layer of ganoine. 
Dermal sense-organs occupying open grooves upon the exoskeleton. 
Dorsal and ventral shields consisting of several symmetrically 
arranged pieces, and the head articulated with the trunk ; orbits 
close together. Paired fins represented by paddle-like appendages 
covered with dermal plates. 

The only family of this order as yet determined with certainty 
is that of the Asterolepidae. 



ASLKKOLIU'ID.K. 203 



Family ASTEROLEPID^. 

Exoskeleton robust, ornamented with tuberculations of ganoine ; 
dorsal and ventral shields of trunk firmly united by the lateral 
plates. Orbits very closely approximated, and the interorbital 
piece loose. A pair of paddle-like appendages, completely encased 
in bony plates, articulated by a complex joint with the anterior 
ventro-lateral plates of the trunk ; median fins not continuous. 

As pointed out especially by Traquair, the dermal plates in the 
genera of this family are arranged upon one definite plan, and the 
most satisfactorily known genus, Pterichthys, may be taken as a 
typical example. This is described in detail under its generic 
heading (p. 208), and notes on the homologous parts of Bothriolepis 
are added later (p. 224). 

Synopsis of Genera. 

I. Pectoral appendages shorter than the body- 

armour. 

Anterior median dorsal plate overlapping the 

dorso-laterals Aster olepis (p. 20-3). 

Anterior median dorsal plate overlapping 
the anterior dorso-lateral, overlapped 
by the posterior dorso-lateral Pterichthys (p. 208). 

Anterior median dorsal plate in front over- 
lapping and behind overlapped by the 
anterior dorso-lateral and the posterior 
dorso-lateral Microbrachium (p. 223). 

II. Pectoral appendages longer than the body- 

armour. 
Anterior median dorsal plate overlapping the 
anterior dorso-lateral, overlapped by the 
posterior dorso-lateral Bothriolepis (p. 223). 

Genus ASTEROLEPIS, Eichwald. 

[Bull. Sci. St.-Petersbourg, vol. vii. 1840, p. 79 (Astr olepis).] 

Syn. Chelonichthys, L. Agassiz, Poiss. Eoss. vol. i. 1844, p. xxxiii 
(name only). 
Odontacanthits, L. Agassiz, Poiss. Foss. V. G. R. 1845, pp. Ill, 

114. 
(?) Actinolepis, L. Agassiz, ibid. p. 141. 
(?) Xarcodes, L. Agassiz, ibid. pp. Ill, 115. 

Head and trunk broad, not much elevated, the scutes ornamented 



204 AN XI ARCH A. 

with tubercles ; [tail unknown]. Lateral sensory canals upon the 
upper aspect of the head united by an anterior transverse commis- 
sure crossing the premedian plate, and by a posterior one directly 
crossing the median occipital ; anterior median dorsal plate over- 
lapping both the anterior and posterior dorso-laterals. Pectoral 
appendages shorter than the armoured trunk, segmented into a 
distal and proximal portion. 

This genus is only known from isolated dermal plates so similar 
in form to those of Pterichthys as to have induced C. H. Pander ] to 
regard the last-mentioned name as a synonym. The only un- 
doubted distinguishing feature, according to R. H. Traquair 2 , is the 
mode of overlapping of the anterior median dorsal plate. The tail, 
however, is still unknown. 



Asterolepis ornata, Eichwald. 

1840. Astrolepis, E. Eichwald, Bull. Sci. St.-P6tersbourg, vol. vii. p. 79. 
1840. Asterolepis ornata, E. Eichwald, Neues Jahrb. p. 425. 

1844. Asterolepis ornatus, E. von Eichwald, Bull. Soc. Imp. Nat. 
Moscou, vol. xvii. p. 829. 

1845. Asterolepis ornata, L. Agassiz, Poiss. Foss. V. G. R. p. 93, pi. B. 
fig. 4 ; pi. xxx. figs. 2-9 (? in part). 

(?) 1845. Asterolepis apicalis, L. Agassiz, op. cit. p. 148, pi. xxxi. a. 

fig. 31. 
1857. Asterolepis, C. H. Pander, Placoderm. devon. Syst. p. 44, pi. v. 

figs. 10, 11, pi. vi. figs. 1-4, pi. vii. figs. 1, 8, pi. viii. fig. 4, pi. B. 

figs. 6, 7, 10, 13, 14. 
1860. Asterolepis ornata, E. von Eichwald, Leth. Rossica, vol. i. p. 1508 

pi. lvi. fig. 1. 

Type. Detached dermal plates ; University of St. Petersburg. 

The type species. Anterior median dorsal plate not carinated 
longitudinally, its anterior extremity almost as broad as the poste- 
rior. Unworn superficial tubercles with prominently stellate bases, 
irregularly arranged, and sometimes fused together; outer margin 
of pectoral appendages acute and coarsely denticulated. 

Form. § Loc. Devonian : Baltic Provinces and Government of 
Novgorod, Russia. 

The following specimens are detached plates from the neighbour- 
hood of Dorpat, and, unless otherwise stated, were obtained by 
purchase, 1868 : — 

41090 a. Premedian. 

1 Die Placodermen des devoniscben Systems (1857), p. 44. 

2 Geol. Mag. [3] vol. v. (1888), p. 508 ; also Ann. Mag. Nat. Hist. [6] vol. ii. 
(1888), p. 492. 



ASTEROLEPID^. 205 

410901). Two examples of postmedian. 

41090 c. Two imperfect large and one small example of median 
occipital. 

41090 d. One left and two right lateral occipitals. 

41090 e. Portion of right anterior ventro-lateral. 

P. 1 a. Portion of left anterior ventro-lateral. Purchased, 1879. 

41091 a. Two examples of articular. 

P. 1 b, C. Large and small similar plates. Purchased, 1879. 

41091 b. Inner second marginal. 

41091 C. Inner proximal marginal. 

41091 d. Outer proximal marginal. 

41091 e. Distal half of anconeal. 

41091 f, g. Two doubtful plates, perhaps distal centrals, 

41091 h. Proximal inner marginal of distal segment. 

41091 i. Two outer distal marginals. 

41091 j. Terminal plate of limb. 

Asterolepis concatenata, Eichwald. 

1844. Pterichthys concatenatus, E. von Eichwald, Bull. Soc. Imp. Nat. 
Moscou, vol. xvii. p. 829. 

1845. Asterolepis concatenata, E. von Eichwald, Archiv f. Mineral., 
Geogn., etc., vol. xix. p. 674. 

(?) 1845. Actinolepis tuberculatus, L. Agassiz, Poiss. Foss. V. G. R. 

p. 141, pi. xxxi. figs. 15-18. 
1845. Chelyophorus pustulatus, L. Agassiz, ibid. p. 136, pi. xxxi. a. 

figs. 20, 21. 
1857. Asterolepis concatenatus, O. H. Pander, Placoderm. devon. Syst. 

p. 102, pi. vii. fig. 7 [? also fragment without name, ibid. pi. vii. 

fig. 25.] 
1860. Asterolepis concatenata, E. von Eichwald, Leth. Rossica, vol. i. 

p. 1509. 

Type. Median occipital plate ; University of St. Petersburg. 

An imperfectly determined species, somewhat smaller than A. 
ornatus, and described as differing in the frequent arrangement of 
the superficial tuberculations in distinct regular series. 

Form. Sf Loc. Devonian : Marjina, near Pawlowsk, Govt, of St. 
Petersburg, Russia. 

Not represented in the Collection. 



206 ANTTATCCKA. 

Asterolepis maxima (Agassiz). 
[Plate V. fig. 1.] 

1845. Coccosteus maximus, L. Agassiz, Poiss. Foss. V. G. R. p. 137, 

pi. xxx. a. figs. 17, 18. 
1848. Pterichthys major, H. Miller (non Agassiz), Quart. Journ. Geol. 

Soc. vol. iv. p. 311. 
1857. Asterolepis, C. H. Pander, Placoderm. devon. Syst. p. 17. 
1860. Coccosteus maximus — Asterolepis ornata, E. von Eichwald, Leth. 

Rossica, vol. i. p. 1508. 
1888. Asterolepis maximus, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 508, and Ann. Mag. Nat. Hist. [6] vol. ii. p. 494, pi. xviii. 

figs. 1, 2. 

Type. Imperfect anterior median dorsal plate ; Geological Society 
of London. 

A very large species, attaining more than twice the size of 
A ornata. Anterior median dorsal plate with a faint longitudinal 
carina ; anterior extremity tapering, its breadth being not more 
than half that of the posterior extremity. Superficial tubercles 
large, rounded, closely arranged, rarely fused together. 

The type specimen of this species was regarded by Agassiz as a 
median ventral plate, but is shown by Miller and Pander to be 
anterior median dorsal, while the last-named author determines its 
correct generic position. 

Form. Sf Loc. Upper Old Red Sandstone : Nairn. 

38710-15. Six imperfect examples of the anterior median dorsal 
plate in various states of preservation. The first specimen 
measures O'lo in length, is exposed from the inner aspect, 
and displays portions of the lateral overlapping edges ; it 
is shown, of one third the natural size, in PI. V. fig. 1. 

Purchased, 1864. 

36001. Smaller anterior median dorsal plate. Purchased, 1861. 

P. 5052. Imperfect impression of a similar plate ; King's Steps. 

Presented by John Edward Lee, Esq., 1885. 

28875. Right posterior dorso-lateral. Purchased, 1854. 

38716. Right posterior dorso-lateral. Purchased, 1864. 

P. 5052 a. Imperfect similar plate, displaying areas overlapped by 
the median dorsals. 

Presented by John Edward Lee, Esq., 1885. 

28875 a. Portion of lateral plate. Purchased, 1885. 



ASTEROLTiriDJB. 



20' 



P. 5052 b. A small imperfect plate, 0*06 in length, probably part 
of a median dorsal ; King's Steps. 

Presented by John Edward Lee, Esq., 1885. 

Fragments of the pectoral appendages of Asterolepis, from the 
Devonian of Russia, are also described under the following names : — 

Odontacanthus crenatus, L. Agassiz, Poiss. Foss. V. G. R. (1845), 

pp. Ill, 115, pi. xxxiii. fig. 7 : Ctenoptychlus crenatus, L. 

Agassiz, Poiss. Poss. vol. iii. (1843), p. 173. — Devonian ; 

Megra. 
Odontacanthus heterodon, L. Agassiz, ibid. (1845), pp. Ill, 115, 

pi. xxxiii. fig. 8. — Devonian ; near Riga. 
barcodes pushdifer, L. Agassiz, ibid. (1845), pp. Ill, 115, 

pi. xxxiii. fig. 9. — Devonian ; near St. Petersburg. 

Dermal plates of Ostracoderms, &c, too imperfect for satisfactory 
determination, have also been assigned to Asterolepis under the 
following names : — 

Asterolepis australis, P. M'Coy, Prodr. Palseont. Victoria (Geol. 
Surv. Vict.), dec. iv. (1876), p. 19, pi. xxxv. fig. 7 (re- 
garded as variety of A. ornata). — Middle Devonian ; 
Buchan River, North Gippsland, Yictoria. [Melbourne 
Museum.] 

Asterolepis bohemica, J. Barrande, Syst. Silur. Boheme, vol. i. 
Suppl. (1872), p. 637, pi. xxix. — Upper Silurian (g 1) ; 
Chotecz, Bohemia. [Royal Bohemian Museum, Prague.] 

Asterolepis depressa, E. von Eichwald, Archiv f. Mineral., Geogn., 
&c, vol. xix. (1845), p. 674, and Leth. Rossica, vol. i. 
(1860), p. 1510 : Pterichthys depressus, E. von Eichwald, 
Bull. Soc. Imp. Nat. Moscou, vol. xvii. (1844), p. 829.— 
Devonian ; Marjina, near Pawlowsk, and River Aa, 
Livonia. [University of St. Petersburg.] 

Asterolepis gramdata, L. Agassiz, Poiss. Poss. V. G. R. (1845), 
pp. 94, 147, pi. xxx. fig. 12, pi. xxx. a. fig. 12. — Devonian; 
Riga. 

Asterolepis malcolmsoni, L. Agassiz, ibid. (1845), p. 147, pi. xxx. a. 
fig. 16. — Upper Old Red Sandstone ; Scat Craig, Elgin. 
[? A. maxima.'] 

Asterolepis minor, L. Agassiz, ibid. (1845), pp. 94, 147, pi. xxviii. a. 
fig. A (in part), pi. xxx. fig. 11, pi. xxxi. a. figs. 29, 30 : 
Asterolepis miliaris, L. Agassiz, ibid. p. 61 : Chelonichihys 



A.NTIABCHA. 

minor, L. Agassiz, Poiss. Foss. vol. i. (1844).. p. xxxiii 

(name only). — Devonian ; Riga and St. Petersburg. Upper 

Old Red Sandstone ; Elgin. [Original of Agassiz, pi. xxx. 

fig. 11, considered as probably referable to Asterolepis 

concatenata by E. von Eichwald, Leth. Rossica, vol. i. 

(1860), p. 1510.] 
Asterolepis speciosa, L. Agassiz, op. cit. (1845), pp. 93, 146, 

pi. xxx. fig. 10, pi. xxx. a. fig. 4. — Devonian; Yoroneje, 

Russia. 
Asterolepis wenhenbachii, C. Koch, Yerhandl. naturh. Yerein., 

Bonn, vol. xxix. (1872), Correspond, p. 85 (name only). 

— Devonian : Eifel. 



Genus PTERICHTHYS, Agassiz. 
[Poiss. Foss. Y. G. R. 1844, p. 6.] 

Head and trunk broad, but much elevated, the scutes ornamented 
with tubercles; tail covered with rounded or hexagonal scales, 
slightly imbricating. Lateral sensory canals on the upper aspect of 
the head united by an anterior transverse commissure crossing the 
premedian plate, and a posterior one directly crossing the median 
occipital ; anterior median dorsal plate overlapping the anterior 
dorso-lateral, overlapped by the posterior dorso-lateral. Pectoral 
appendages shorter than the armoured trunk, segmented into a 
distal and proximal portion ; marginal scutes of proximal portion 
separated above and below by a median " anconeal " element ; 
marginal and central scutes of distal portion few. A single small 
median dorsal fin, with large anterior fulcral scales, but apparently 
no fin-rays. 

The exoskeleton of this genus is now tolerably well known, 
owing especially to the researches of Miller, Pander, and Traquair ; 
and the accompanying restorations (fig. 33, A, B, C) are those of the 
last-named author. Fig. A represents the dorsal aspect, and fig. B 
the ventral aspect, while fig. C is a side view. The exposed margins 
of the plates of the trunk are shown by thickened lines, while the 
amount and direction of their overlap are indicated by the thin 
lines. Sensory canals, both upon the head and trunk, are marked 
by double dotted lines. We would only add that the large inferior 
expansion of the caudal fin is omitted in the third figure (compare 
PI. YI. fig. 3, x) ; and for the details of the hard parts in the 
orbital opening, reference must be made to some of the specimens 
described below, notably the original of PI. Y. fig. 2. 

The cranial shield is small compared with the armour of the 



ASTEROLEPIDJE. 



209 



trunk, and, so far as known, is confined to the dorsal and lateral 
aspects. A large transverse opening, somewhat constricted mesially, 
occurs in the middle of the roof ; and all the constituent plates of 

Fig. 33. 




Pterichthys testudinarius, Ag. ; restored by R. H. Traquair, from the dorsal 
aspect (A), ventral aspect (B), and lateral aspect (C). In the last figure 
the caudal fin is omitted. The double dotted lines indicate the grooves 
of the sensory canal-system ; and in the trunk, the thick lines repre- 
sent the exposed borders of the plate, the thin line showing the 
extent of the overlap, a., anconeal; a.d.l., anterior dorso-lateral ; a.m.d., 
anterior median dorsal ; a.v.l., anterior ventro-lateral ; ag., angular; ar., 
articular; c, central; e.L, extra-lateral (or operculum); l.occ, lateral 
occipital ; m., marginal ; m.occ, median occipital ; m.v., median ventral ; 
mn., mental; p.m., premedian; p.d.l., posterior dorso-lateral; p.m.d., 
posterior median dorsal; p.vd., posterior ventro-lateral; pt.m., post- 
median ; &.I., semilur ar, 

PART II. P 



210 ANTIA.RCIIA. 

the shield, except the postero-lateral pair, are firmly fixed together by 
sutures. There is a crown-shaped median occipital (m.occ), 
bounded upon either side by a somewhat smaller lateral occipital 
(l.occ.), and separated from the great opening in front by a narrow, 
transversely elongated, postmedian plate (pt.m.). A very small, 
approximately quadrate angular plate (ag.) adjoins the outer 
margin of the lateral occipital on each side ; and a long, narrow, 
lateral element (I) extends on each side of the median opening from 
the front margin of these plates continuously to the rostral border 
of the shield. A large single premedian plate (p.m.) is interposed 
between the anterior extremities of these laterals, forming both the 
front border of the median opening and the extremity of the snout. 
The narrow space on each side, between the lateral and angular 
plates and the anterior border of the armour of the trunk, is filled 
by a loose extra-lateral plate (e.l.), which seems to have formed the 
operculum ; its posterior margin was evidently free, but its anterior 
strongly convex margin is notched in such a manner as to suggest 
the ordinary articulation of a fish-operculum (see PL V. fig. 6). 
The orbits seem to have occupied the rounded extremities of the 
great median opening, these being separated by a thick, loose, 
quadrate plate, with laterally produced hinder angles, well shown 
from the inner aspect in PL V. fig. 2, p; this element (the " os 
dubium " of Pander) is ornamented externally, but exhibits a deep 
pit in the middle of its inner face, evidently for the reception of the 
pineal body, and it may thus be known as the pineal plate. 
Immediately in |ront of the latter there seems to be a thin, narrow 
bone (see No. 19804 a, p. 222), but this has not yet been clearly 
observed. In the position of the orbits themselves, a thin, oval, 
convex or concave, smooth plate is often observed ( PL V. fig. 2, o), 
and this may probably be interpreted as an ossification in the 
sclerotic. 

The sensory canals upon the cranial shield are nearly parallel 
with its border, one directly crossing the median occipital plate 
transversely, another similarly crossing the premedian, and a lateral 
pair extending along the long axis of the laterals. These and the 
transverse hinder canal meet in an angulation on the lateral 
occipitals, whence also a branch runs along the dorso-lateral plates 
of the trunk, forming the " lateral line." 

The head seems to have been movably articulated with the 
trunk, out not by any ginglyraoid processes or surfaces. The dermal 
armature apparently extends over the whole of the abdominal 
region, but does not include the anus. Its ventral surface is 
flattened, while the dorsal shield is much arched ; and all the 
plates are deeply overlapping. There are two median dorsal 



ASTEK0LEPID.1S. 



211 



elements, the anterior (a.m.d.) larger than the posterior (p.in.d.) ; 
and these are bounded by two dorso-lateral pairs (a.d.L and p.d.l.), 
of which the hinder is much the largest. There are two pairs of 
ventro-lateral plates (a.v.l. and p.v.l.), which meet in the mesial line 
below, and are sharply reflexed upwards at the sides to overlap the 
inferior edge of the dorso-laterals ; while on the ventral surface 
there occurs a small, median, diamond-shaped space between the 
inner truncated angles of these plates, filled by a much-overlapped 
median ventral (m.v.). The slightly excavated front border of the 
anterior ventrolaterals is filled by a pair of small semilunar plates 
(s.l.) tapering outwardly ; and again in advance of these is a pair of 
much larger, transversely elongated elements (mn.), concave above, 
which have been termed mental by Traquair. The latter plates are 
loosely fixed and often displaced (see PI. V. fig. 3, mn.), but can 
scarcely be interpreted as a mandible. At a point somewhat in 
advance of their hinder extremities, the posterior ventro-lateral 
plates are distinctly constricted, with an inner transverse thickening ; 
and this may mark the termination of the abdominal cavity. 

Near their front extremity the anterior ventro-lateral plates are 
strengthened by a robust transverse ridge on the visceral aspect, 
and close to this the pectoral appendages are fixed by a most 
complex, ginglymoid articulation. Each appendage is completely 
encased in closely-fitting plates ; and a large orifice in the 
supporting articular facette bears witness to the passage into its 
interior of well-developed vascular canals and nerves. A powerful 
articular plate (ar.), with rounded proximal end, occurs both on the 
dorsal and on the ventral aspect of the appendage ; an inner and 
an outer marginal (w.), with an upper and a lower median anconeal 
plate («.), are closely united with these, and at the distal extremity 
of this group of plates the appendage is jointed. The distal 
segment is shorter and smaller than the proximal, consisting of an 
upper and lower central piece (c.J, a pointed terminal plate (u\ and 
two pairs of marginals (m.). 

The tail is comparatively small, covered with imbricating rounded 
or hexagonal scales, with a series of large azygous ridge-scales on 
the dorsal aspect. The body-scales are thin and finely tuberculated 
(see Nos. P. 3209, P. 4036), while the dorsal ridge-scales are 
comparatively robust. The latter are interrupted shortly behind 
the posterior median dorsal plate by a small triangular dorsal fin ; 
this being membranous, and only stiffened on its front margin by one 
(or perhaps two) of the scales, which might be mistaken for a spine. 
Behind the fin, the ridge-scales are very deeply imbricating to the 
extremity of the tail, which is somewhat upturned (PL V. fig. 5), 



212 ANTIARCHA. 

and is bordered below by a large membranous caudal fin (PI. VI. 
fig. 3, .r) of uncertain shape. There are no pelvic fins, the 
determination of their presence by Egerton l being founded upon a 
mistake 2 . 



Pterichthys milleri, Agassiz. 
[Plate V. figs. 2-7.] 
v 1841. Pterichthys milleri, H. Miller {ex Agassiz), Old Red Sandstone, 
■"" p. xxii, pis. i. & ii. 
1844. Pterichthys milleri and P. lotus, L. Agassiz, Poiss. Foss. vol. ii. 

pt. i. p. 302 (names only). 
1844. Pterichthys latus, L. Agassiz, Poiss. Foss. V. G. R. p. 12, pi. iii. 

figs. 3, 4. [British Museum and Forres Museum.] 
1844. Pterichthys milleri, L. Agassiz, ibid. p. 15, pi. i. figs. 1-3. 
1848. Pterichthys quadratus, Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. iv. p. 313, pi. x. [Geological Society of London.] 
1848. Pterichthys latus, Sir P. Egerton, ibid. p. 312. 
1855. Pterichthys latus, F. M'Coy, Brit. Palseoz. Foss. p. 600. 
1888. Pterichthys milleri, R. H. Traquair, Geol. Mag [3] vol. v. p. 509. 

Type. Head, trunk, and base of tail, ventral aspect ; Edinburgh 
Museum. 

The type species. Inferior surface of carapace broadly ovate ; 
tail about equal in length to the trunk. Pectoral appendages two- 
thirds as long as the trunk, not expanded, tapering. 

Form. Sf Loc. Lower Old Red Sandstone : Cromarty, Banffshire, 
and Nairnshire. 

P. 6259. Paper model of carapace, made by Hugh Miller. 

Egerton Coll. 

(i.) Cromarty (typical P. milleri). 

19804. Imperfectly preserved small specimen in counterpart. 

Purchased, 1845. 

P. 654. Imperfect similar specimen, wanting head ; bearing auto- 
graph of Hugh Miller. Egerton Coll. 

P. 3213. Small crushed trunk and head, in counterpart. 

EnnisTcillen Coll. 

21974. Imperfect head, trunk, and pectoral appendages, ventral 
aspect, as large as the typical P. latus. Purchased, 1848. 

1 Quart, Journ. Geol. Soc. vol. xvi. (1860), p. 127. 

■ E. H. Traquair, Geol. Mag. [3] vol. v. (1888), p. 509. 



ASTEROLEPID.E. 



213 



P. 5599. Remains of a large trunk, with the right pectoral appen- 
dage, ventral aspect. Purchased, 1889. 

(ii.) Lethen Bar (typical P. latus). 

P. 533. One of the type specimens of P. latus, figured by Agassiz, 
op. cit. pi. iii. fig. 4. As remarked by Egerton, the fossil 
exhibits the ventral aspect, and most of the bone- 
substance is removed. Egerton Coll. 

28857. Crushed individual, dorsal aspect. The parts of the head 
are mostly obscured, but the mental plates are distinguish- 
able, and the pineal or " os dubium," with its median pit, 
is well shown. The anterior median dorsal plate is 
almost destroyed, but the smaller second dorsal is more 
complete ; and immediately below and behind the latter 
occur the hinder extremities of the posterior ventro- 
laterals. Nothing worthy of note is presented by the tail ; 
but in the left pectoral appendage, the transversely 
striated ginglymus upon which the distal segment moves 
is distinct. Purchased, 1854. 

49187. Trunk with head and fragments of the appendages and tail, 
ventral aspect, preserved in counterpart. The head is 
completely severed from the trunk, and the roof is shown 
from beneath, of the natural size, in PI. V. fig. 2. In 
addition to some of the elements ordinarily observed, and 
marked with letters in the figure, the pineal plate (p.) is 
well seen, with its central pit, and also one of the orbital 
plates (o.) ; moreover, a small process is observed to 
extend from the middle of the anterior margin of the 
postmedian plate (pi. m.). One of the extra-lateral plates 
is detached ; and the plates of the 1 '' appendages are 
scattered and broken. Purchased, 1878. 

49191. Head, trunk, limbs, and scattered remains of the tail, 
ventral aspect, preserved in counterpart. The posterior 
ventro-lateral plates exhibit denticulations on the hinder 
margin. Purchased, 1878. 

50109. Nearly complete individual, dorsal aspect, much crushed, and 
preserved in counterpart. The specimen is shown of the 
natural size in PI. V. fig. 3. In the head the most 
important feature displayed is the pair of mental plates 
(mn.) ; they are somewhat displaced forwards, and their 
superior (or visceral) aspect ia distinctly concave. The 



214 AXTIARCHA. 

extra-laterals (e.l.) are also shown, almost in their natural 
position. As far as the hinder margin of the anterior 
median dorsal plate, the roof of the carapace is preserved, 
but more posteriorly the posterior ventro-laterals are 
exposed from the visceral aspect, and the posterior median 
dorsal plate is seen only in impression in the counterpart. 
The anterior median dorsal (a.m.cl.) is slightly narrower 
in front than behind, and its longitudinal keel rises to a 
prominent apex in the centre. The anterior dorso-lateral 
plates (a.d.l.) distinctly overlap the posterior dorso-laterals 
(p.d.l.); and the usual constriction near the hinder 
extremity of the posterior ventro-laterals (p. v. I.) is well 
seen. The cycloidal scales of the tail exhibit no features 
worthy of special note ; and the large fulcral scale at the 
anterior margin of the dorsal fin {d.), though preserved, 
is apparently much broken. Purchased, 1879. 

50110. Individual with incomplete head, preserved in counterpart, 
and shown of the natural size in PI. V, fig. 4. Many of 
the plates are distinctly exhibited, notably the right 
posterior ventro- lateral ; and the form and proportions of 
the pectoral appendages are indicated. Towards the 
extremity of the tail occur traces of the dorsal fulcral 
scales (/.) ; and a ferruginous stain may indicate the 
original presence of a terminal fin, or may be merely an 
aggregation of mineral matter round the point. 

Purchased, 1879. 

P. 6262. Portions of the head and pectoral appendages, and the 
ventral plates seen from the visceral aspect. 

P. 658, P. 3204. Two examples of the imperfect trunk, in counter- 
part, ventral aspect. Egerton 6f EnnisTcillen Colls. 

28858. Portions of head and trunk, with pectoral appendages. 

Purchased, 1854. 

P. 659. Tail, labelled P. latus by Agassis, showing dorsal fin 
accidentally divided and appearing as if a pelvic pair ; 
noticed by R. H. Traquair, Geol. Mag. [3] vol. v. p. 509. 

Egerton Coll. 

(iii.) Tynet Burn (typical P. latus). 
37985. Imperfect head and trunk, displaying several plates. 

Purchased, 1S63. 



ASTEBOLEFID.K. 



215 



44587. Crushed remains of head and trunk, portions showing the 
ornamentation of closely-arranged rounded tubercles. 

Purchased, 1873. 

35981. Imperfect individual, wanting almost the whole of the 
tail. A few of the head-plates and the operculum (or 
extra-lateral) are well displayed, the latter being shown 
in PI. V. fig. 6. The hinder edge of the posterior ventro- 
lateral plates of the trunk is coarsely denticulated. 

Purchased, 1861. 

35980. Crushed remains of armour of trunk, with the anterior 
median dorsal plate showing its overlapped postero-lateral 
border (PI. V. fig. 7). Purchased, 1861. 

(iv.) Gamrie (typical P. quadratus). 

28856. Ventral plates of small trunk, visceral aspect. 

Purchased, 1854. 

28860. Imperfect specimen as large as the type, ventral aspect, 
with right pectoral appendage. Purchased, 1854. 

50G05. Small trunk, ventral aspect, showing portions of the 
tubercular ornament ; the tubercles displayed are stellate. 

Trevelyan Bequest. 

P. 663-4, P. 3205-7, P. 3209. Seven split nodules, each with an 
imperfect specimen in counterpart, five exhibiting the 
ventral aspect, the sixth the dorso-lateral, and the seventh 
the dorsal. The tuberculations of the dermal plates are 
often shown ; and in the last-mentioned specimen fine 
tubercles are seen upon the caudal scales. 

Egerton <Sf Enniskillen Colls. 

28356 e. Trunk, with fragments of head and appendages, ventral 
aspect. Purchased, 1854. 

47868. Crushed individual, ventral aspect, wanting the greater 

portion of the tail. Purchased, 1877. 

47869. Much crushed and broken individual, dorsal aspect. 

Purchased, 1877. 

P. 4035. Crushed individual, ventral aspect, in counterpart, with 
traces of dorsal fin. Purchased, 1883. 

P. 4036. Much, crushed individual, lateral aspect, in counterpart, 
shown, of the natural size, in PI. V. fig. 5. The head is 
almost wanting, but some of the plates of the trunk are 



216 ANTIAECHA. 

distinguishable, and the tail is well shown. The caudal 
scales are externally tuberculated and deeply overlapping ; 
and the dorsal ridge-scales (/.) beyond the fin are very 
distinct. The impression of one large fulcral scale is 
seen upon the anterior margin of the dorsal fin (cL). 

Purchased, 1883. 

Pterichthys testudinarius, Agassiz. 
[Plate Y. fig. 8; Plate VI. fig. 1.] 

1844. Pterichthys cornutus and P. testudinarius, L. Agassiz, Poiss. Foss. 

vol. ii. pt. i. p. 302 (names only). 
1844. Pterichthys testudinarius, L. Agassiz, Poiss. Foss. V. G. R. p. 14, 

pi. iv. figs. 1-3. 
1844. Pterichthys cornutus, L. Agassiz, ibid. p. 17, pi. ii. figs. l-o. 

[British Museum.] 
1848. Pterichthys testudinarius, Sir P. Egerton, Quart. Journ. Geol. 

Soc. vol. iv. p. 312. 
1848. Pterichthys cornutus, Sir P. Egerton, ibid. p. 313. 
1855. Pterichthys testudinarius, F. M'Coy, Brit. Palseoz. Foss. p. 600. 
1888. Pterichthys cornutus, ~R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 509, and Ann. Mag. Nat. Hist. [6] vol. ii. pi. xvii. figs. 1-3. 

Type. Head and trunk ; Edinburgh Museum. 

Inferior surface of carapace narrowly ovate ; tail about equal in 
length to the trunk. Pectoral appendages less than two-thirds as 
long as the trunk, not expanded, tapering. 

Form. <Sf Log. Lower Old Red Sandstone : Lethen Bar, Nairn- 
shire. ' 

P. 3202. One of the type specimens of P. cornutus, figured by 
Agassiz, op. cit. pi. iv. fig. 2. Enniskillen Coll. 

P. 548, P. 3203. One of the type specimens of P. cornutus, in 
counterpart, figured ibid. fig. 4. 

Egerton <$f Enniskillen Colls. 

P. 549, P. 3201. One of the type specimens of P. cornutus, in 
counterpart, figured ibid. fig. 5. 

Egerton Sf Enniskillen Colls. 

28857 a. Ventral plates of trunk, visceral aspect, with right pec- 
toral appendage and remains of tail. Purchased, 1854. 

49190. Trunk, ventral aspect, wanting the tail, with displaced head 
and scattered plates of the carapace. The greater portion 
of the specimen is shown, of the natural size, in PI. V. 
fig. 8, and the various plates are indicated by the letter- 
ing. Purchased, 1878. 



ASTEROLEPID.E. 217 

P. 655. Much crushed, imperfect specimen. Egerton Coll. 

P. 655 a. Small specimen, wanting head. Egerton Coll. 

P. 5053. Small specimen, in counterpart, scarcely crushed, wanting 
the head. The half exhibiting the ventral plates from 
the visceral aspect is shown, of the natural size, in PL VI. 
fig. 1. The various elements are indicated by the letter- 
ing, and some of the overlapping margins of the plates are 
well seen. Presented by J. E. Lee, Esq., 1885. 



Pterichthys productus, Agassiz. 
[Plate Y. fig. 9 ; Plate VI. fig. 2.] 

1844. Pterichthys productus and P. cancriformis, L. Agassiz, Poiss. 

Foss. vol. ii. pt. i. p. 302 (names only). 
1844. Pterichthys productus, L. Agassiz, Poiss. Foss. V. G. R. p. 16, 

pi. v. figs. 1-4. 
1844. Pterichthys cancriformis, L. Agassiz, ibid. p. 17, pi. i. figs. 4, 5, 

[British Museum.] 
1848. Pterichthys productus, Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. iv. p. 312. 
1855. Pterichthys cancriformis, F. M'Coy, Brit. Paleeoz. Foss. p. 509. 
1855, Pterichthys productus, F. M'Coy, ibid. p. 600. 
1880. Pterichthys, J. Lahusen, Verhandl. russ.-kais. mineral. Gesell. [2] 

vol. xv. pi. ii. fig. a. 
1888. Pterichthys productus, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 509. 

Type. Imperfect individuals, ventral aspect; British Museum 
and Forres Museum. 

Inferior surface of carapace narrowly ovate ; tail about equal in 
length to the trunk. Pectoral appendages about two-thirds as long 
as the trunk, the distal segment considerably expanded. 

Form. 6f Loc. Lower Old Red Sandstone : Nairnshire, Banffshire, 
Ross-shire, and Orkney. 

(i.) Lethen Bar. 

P. 534, P. 3212. One of the type specimens, in counterpart, figured 
by Agassiz, op. cit. pi. v. fig. 1. The fossil exhibits the 
ventral aspect of the head and trunk and right pectoral 
appendage, much broken, and is re-figured in PI. V. fig. 9, 
with explanatory lettering. Egerton <Sf Enniskillen Colls. 

P. 547. Counterpart of one of the type specimens figured by Agassiz. 
op. cit. pi. v. fig. 2. Egerton Coll. 



218 ANTIARCHA.. 

28359, 39175. Much crushed individual, in counterpart, exhibiting 
the lateral and partly dorsal aspect. The elements of the 
head are almost unrecognizable, and those of the trunk 
and appendages are imperfectly displayed. The dorsal 
fin upon the tail is distinct, with remains of its fulcral 
6cale ; and more posteriorly is observed the series of large 
dorsal ridge-scales. 

Purchased, 1854, and Bowerbanh Coll. 

4S188. Head, trunk, appendages, and fragment of tail, ventral 
aspect, preserved in counterpart. In the head, the " os 
dubium " or pineal plate, with its central pit, is well shown. 

Purchased, 1878. 

50108. Large specimen wanting the tail and the extremities of the 
appendages. The trunk measures 0*078 in length, ex- 
hibiting the ventral aspect, and the roof-plates of the head 
are seen from beneath. Most of the latter are well shown, 
and as their substance is partly destroyed, the course of 
the sensory canal upon the laterals and premediau can 
be traced. The extra-laterals are detached. 

Purchased, 1879. 

50111. Well-preserved specimen, ventral aspect, in counterpart, the 
impression shown of the natural size in PL YI. fig. 2, and 
explained by the lettering. The tail is somewhat twisted, 
thus exhibiting the dorsal fin. Purchased, 1879. 

50113. Small specimen, wanting the tail, ventral aspect. 

Purchased, 1879. 

P. 3211. Much crushed specimen, ventral aspect, wanting appen- 
dages. EnnisTcillen Coll. 

P. 4037. Small head and trunk, ventral aspect, in counterpart. 

Purchased, 1883. 

(ii.) Tynet Burn. 

44588. Small imperfect crushed specimen, ventral aspect. 

Purchased, 1873. 

(iii.) Edderton, near Tain. 
P. 1172. Much crushed and broken individual. Egerton Coll. 

(iv.) Orkney (typical P. cancriformis). 
P. 532. One of the type specimens of P. cancriformis figured by 



ASTEROLEI>IDJE. 



219 



Agassiz, op. cit. pi. i. fig. 4. The trunk is seen from tbe 
ventral aspect, but its correct outline is apparently de- 
stroyed. Egerton Coll. 

P. 3208 a. Second type specimen of P: cancriformis, figured ibid. 
fig. 5. EnnisJcillen Coll. 

34987-89. Two large specimens exhibiting tbe tail, and one small 
specimen. Purchased, I860. 

35047. Imperfect large specimen ; Stromness. Purchased, 1860. 

38731-32. Small specimen and portion of larger individual. 

Purchased, 1865. 

41998. Comparatively well preserved specimen, ventral aspect, 
showing displaced mental plates ; Stromness. 

Purchased, 1870. 

P. 660-2. Small distorted specimen and two more imperfect larger 
examples ; Belyacreugh. Also a fragment, with pectoral 
appendages, from Ramna Gio. Egerton ColL 

P. 3208. Two specimens, ventral aspect. EnnisTcillen ColL 

Pterichthys oblongus, Agassiz. 
[Plate Y. fig. 10 ; Plate VI. figs. 3, 4.] 

1844. Pterichthys oblongus, L. Agassiz, Poiss. Foss. vol. ii. pt. i. p. 302 

(name only). 
1844. Pterichthys oblongus, L. Agassiz, Poiss. Foss. V. G. R. p. 18 r 

pi. iii. figs. 1, 2. 
1848. Pterichthys oblongus, Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. iv. p. 313. 
1855. Pterichthys oblongus, F. M'Coy, Brit. Palaeoz. Foss. p. 600. 
1888. Pterichthys oblongus, R. H. Traquair, Geol. Mag. [3] vol. v, 

p. 509. 

Type. Imperfect trunk and tail, ventral aspect ; Elgin Museum. 

Inferior surface of carapace long and narrow, sides nearly straight ; 
tail shorter than the trunk. Pectoral appendages less than two 
thirds as long as the trunk, the distal segment considerably ex- 
panded. 

Form. Sf Loc. Lower Old Red Sandstone : Banffshire, Nairnshire, 
and Cromarty. 

(i.) Gamrie. 
28856 a. Imperfect specimen, ventral aspect, in counterpart. 

Purchased, 1854. 



220 ANTIARCHA. 

28856 1). Imperfect specimen, ventro-lateral aspect, in counterpart. 

Purchased, 1854. 

28856 C. Small trunk, ventral aspect, with portions of appendages. 

Purchased. 1854. 

34991. Ventral plates, visceral aspect, and other fragments. 

Purchased, 1860. 

50006. Eemains of small head and trunk, ventral aspect. 

Purchased, 1878. 

37767. Small specimen, ventral aspect, wanting head and left 
pectoral appendage. Purchased, 1863. 

P. 664 a, P. 3209 a. Crushed and broken individual, ventral aspect, 
in counterpart, shown, of the natural size, in PI. VI. rig. 3. 
The head is wanting, and only portions of the appendages 
are preserved. The tubercular ornament is seen not only 
upon the plates of the truDk and appendages, but also 
upon the caudal scales. The dorsal fin (d.) occurs some- 
what displaced ; the dorsal ridge-scales (/.) towards the 
extremity of the tail are distinct ; and remains of the 
large lower lobe of a caudal fin (a,\) are also conspicuous. 

Egerton Sf EnnisJcillen Colls. 

P. 663-4, P. 3209. Head and trunk, dorso-lateral aspect, in counter- 
part, and a smaller specimen, ventral aspect, also in 

counterpart. Egerton Sf EnnisJcillen Colls. 

1 
P. 3210. Two imperfect specimens, ventral aspect. 

Enniskillen Coll. 

28856 d. Crushed and broken trunk, ventral aspect. 

Purchased, 1854. 

(ii.) Lethen Bar. 

30875. Eemains of trunk and right pectoral appendage, ventral 
aspect. Purchased, 1856. 

39174. Imperfect specimen, ventral aspect, displaying expansion of 
the left pectoral appendage, as shown in PL V. fig. 10. 

Bowerhank Coll. 

40323. Imperfect specimen, wanting tail, ventral aspect, in counter- 

part. Purchased, 1867. 

40324. Much crushed and broken specimen, ventral aspect, showing 

expansion of pectoral appendage. Purchased, 1867. 



ASTER0LEPID2E. 221 

48163. Trunk and portions of head and tail, ventral aspect, in 
counterpart. The displaced " os duhium " is shown, and 
one of the orbital plates is exhibited in the dorsal opening 
of the head. Purchased, 1877, 

49189. Small individual with imperfect head and tail, ventral 
aspect, in counterpart. The left extra-lateral plate is seen 
displaced ; the expansion of the pectoral appendages is 
distinct; and two or three of the dorsal ridge-scales upon 
the tail are exhibited. Purchased, 1878. 

50107. Imperfect head and trunk, ventral aspect, in counterpart, 

shown, of the natural size, in PI. VI. fig. 4. In the 
orbital opening, the " os dubium " (p.) and the two 
orbital plates are exhibited. The left pectoral append- 
age displays the characteristic distal expansion. 

Purchased, 1879. 

50108. Crushed individual, wanting extremities of appendages, 

ventral aspect. The tubercular ornamentation of the 
ventral plates is well shown in impression. 

Purchased, 1879. 

50112. Imperfect crushed trunk with right pectoral appendage, 
remains of the head, the greater portion of the tail and 
dorsal fin. Purchased, 1879. 

P. 657. Two imperfect specimens, ventral aspect, one displaying 
the left pectoral appendage. Egerton Coll. 

P. 6071. Ventral plates of trunk, fragments of left pectoral appen- 
dage and tail. Presented by F. Harford, Esq., 1889. 

P. 4038. Trunk 0-035 in length, with portions of appendages and 
tail, ventral aspect, in counterpart, probably young of this 
species. Purchased, 1883. 

(iii.) Tynet Burn. 

37781. Much crushed trunk, ventro-lateral aspect, showing left 
pectoral appendage and fragments of head and tail. The 
tubercular ornameutation is well displayed. 

Purchased, 1863. 

35979. Large specimen, ventral aspect, doubtfully of this species. 
The displaced mental plates are seen from their concave 
visceral aspect ; the internal transverse ridge upon the 
anterior ventro- laterals is distinct; and the tubercular 



222 ANT1ARCHA. 

ornament both of the ventral plates and caudal scales is 
shown in impression. Purchased, 1861. 

(iv.) Cromarty. 

19052, 19055, 19059. Three imperfect examples of the trunk, 
ventral aspect, the first also showing traces of the tail, 
and the third, of the head. Purchased, 1845. 

19804 a. Imperfect specimen displaying the inner aspect of the dorso- 
lateral and median dorsal plates, and characteristic por- 
tions of the expanded appendages. In the orbital opening 
the " os dubium " is distinctly separated from the right 
orbital plate, and there is a trace possibly of an anterior 
plate in advance of the former. The scales of the tail are 
observed to be tuberculated. Purchased, 1845. 

47870. Much crushed trunk and appendages, in counterpart, showing 
ornamentation. Purchased, 1877. 



Pterichthys rhenanus, Bey rich. 

1855. Physichthys hoeninghausi, H. von Meyer (errore), Palaeontogr. 
vol. iv. p. 80, pi. xv. fig. 7. [Anterior median dorsal plate ; Cam- 
bridge Museum, Mass.] 

1877. Pterichthys rhenanus, E. Beyrich, Zeitschr. deutsch. geol. Gesell. 
vol. xxix. p. 751, pi. x. 

Type. Dermal armour of trunk ; Berlin Museum. 

Inferior surface of carapace broadly ovate. Anterior median 
dorsal plate as broad as long, extremely elevated, the longitudinal 
ridge bent at a right angle slightly behind the middle point; posterior 
median dorsal plate two thirds as long as the anterior median. 

Form. Sf hoc. Devonian : Gerolstein, Eifel. 

Xot represented in the Collection. 

Dermal plates of Antiarcha (and probably other Chordate types), 
too imperfect for satisfactory determination, have also been assigned 
to Pterichthys under the following names : — 

Pterichthys arenatus, L. Agassiz, Poiss. Foss. V. G. R. (1845), 
p. 133, pi. xxx. a. fig. 3. — Devonian ; St. Petersburg. 

Pterichthys cellulosus, C. H. Pander in A. von Keyserling, Beise 
in das Petschoraland (1846), p. 292 a.— Devonian ; Pet- 
chora Land, N.E. Russia. 

Pterichthys elegans, C. H. Pander, Monogr. Foss. Fische Silur. 



ASTEROLEPID-K. 



223 



Syst. (1856), p. 63, pi. v. fig. 10.— Upper Silurian; Baltic 

Provinces 1 . 
PUrichthys harderi, C. H. Pander, ibid. p. 63, pi. v. fig. 9.— 

Upper Silurian ; Baltic Provinces l . 
PUrichthys striatus, C. H. Pander, ibid. p. 63, pi. v. fig. 11. — 

Upper Silurian ; Baltic Provinces. [Not Pterichthys.'] 



Genus MICROBRACHIUM, Traquair. 
[Geol. Mag. [3] vol. v. 1888, p. 510.] 

Form and proportions of head and trunk as in Bothriolepis, but 
pectoral appendages relatively small. The anterior median dorsal 
plate very broad ; " its antero-lateral margin on each side first en- 
velops the anterior dorso-lateral, and is then overlapped by it, the 
relation of the plates to each other being thus suddenly reversed; 
behind this the postero-lateral and posterior margins of the plate 
are overlapped by the posterior dorso-lateral and the posterior dorso- 
median. The last-mentioned plate shows posteriorly a prominent 
angular point, projecting over the hinder opening of the carapace.'' 
(Traquair.) 

A single small species, not represented in the Collection, is 
described thus : — 

M icrobrachiam dicki, R. H. Traquair, Geol. Mag. [3] vol. v. (1888), 
p. 510, and Ann. Mag. Nat. Hist. [6] vol. ii. (1888), 
p. 502, pi. xviii. figs. 7, 8 : Pterichthys dickii, C. W. Peach, 
Rep. Brit. Assoc. 1867 (1868), Trans. Sect. p. 72 (name 
only). — Lower Old Red Sandstone ; John-o'-Groats, Caith- 
ness. [Edinburgh Museum.] 



Genus BOTHRIOLEPIS, Eichwald. 
[Bull. Sci. St.-Petersbourg, vol. vii. 1840, p. 79.] 

Syn. Pamphractus, L. Agassiz, Poiss. Foss. V. G. R. 1844, pp. 5, 20. 
Placothorax, L. Agassiz, ibid. 1845, p. 134. 
Homothorax, L. Agassiz, ibid. 1845, p. 184. 
Glyptosteus, L. Agassiz, Poiss. Foss. vol. i. 1844, p. xxxiv (name 

only). 
Stenacanthus, J. Leidy, Proc. Acad. Nat. Sci. Philad. vol. viii. 

1857, p. 11. 

1 These species are regarded as possibly founded upon fragments of Astero- 
Upis omata by E. yon Eichwald, Leth. Rossica, vol. i. (1860), p. 1507. 



2:24 ANTIA.RCHA. 

Head and trunk broad, depressed, the scutes ornamented with 
tubercles partially or completely fused into a network of ridges ; 
tail [if present] without dermal armature. Lateral sensory canals 
on the upper aspect of the head united by two transverse commis- 
sures arising from a point on the lateral iDlates, the anterior directly 

Fig. 34. 




Head of Bothriolepis canadensis, "Whit. — Dorsal aspect, restored by R. H. Tra- 
quair. ag, angular ; e.l, extra-lateral (operculum) ; I, lateral ; l.occ, lateral 
occipital ; m.occ, median occipital ; p, postmedian ; jp.m, premedian. 

crossing the premedian, the posterior arched backwards, its right 
and left halves meeting in a sharp angulation upon the median 
occipital ; anterior median dorsal plate overlapping the anterior 
dorso-lateral and overlapped by the posterior dorso-lateral, the two 
halves of a commissure arising from the lateral sensory canals on 
the posterior dorso-lateral plates meeting in an acute angle about 
the middle of its surface. Pectoral appendages at least as long as 
the armoured trunk, segmented into a distal and proximal portion, 
the latter being much larger than the former : marginal scutes of 
proximal portion meeting mesially, with a minute " anconeal " 
element only on the dorsal aspect ; marginal and central scutes of 
distal portion more numerous than in PterichtJiys. 

The form and arrangement of the bones occupying the orbital 
opening of this genus have been discovered and described in detail 
by Whiteaves \ The present writer has had the privilege of ex- 
amining the original specimens of the Canadian species elucidating 
the points made known, and is thus able to confirm all the deter- 
minations. The arrangement is very similar to that described above 
in Pterichthys (p. 210) ; but additional information as to the pre- 
cise form of the narrow, transversely-elongated plate in front of the 
pineal element is afforded thus : — " The central portion of the little 
plate is continued downward at nearly a right angle, as a narrow 

1 Trans. Roy. Soc. Canada, vol. iv. sect. iv. (1867), p. 102 ; pi. vi. 



AlsTEJIOLEPlDJS 



225 



linear process, less than 001 in breadth, and about 0-004 in 
length ; after which it widens, at a right angle to the longer axis 
of the body, into a small and narrowly pentangular expansion about 
0*002 broad and 0*003 in length, which reaches nearly as far as the 
inner surface of the anterior ventral plates, though these are very 
much crushed up wards. "' 



Bothriolepis ornata, Eichwald. 

1840. Bothryolepis prisca, E. Eichwald, Neues Jahrb. p. 425 (name 

only). 
1840. Bothriolepis ornatus, E. Eichwald, Bull. Sci. St.-Pe'tersbourg, 

vol. vii. p. 79. 

1844. Glyptosteus reticulatus, L. Agassiz, Poiss. Foss. vol. i. p. xxxiv 
(name only), in part. 

1845. Bothriolepis ornatus, L. Agassiz, Poiss. Foss. V. G. R. p. 99 (in 
part), pi. xxix. figs. 1, 2 (non figs. 3-5). 

1857. Asterolepis, C. H. Pander, Placoderm. devon. Syst. p. 44. 

1860. Bothriolepis ornata, E. von Eichwald, Leth. Rossica, vol. i. 

p. 1513, pi. lvi. fig. 3. 
1880. Bothriolepis ornata, J. Lahusen, Verhandl. russ.-kais. mineral. 

Gesell. [2] vol. xv. p. 136. 
1888. Bothriolepis ornatus, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 509. 

Type. Anterior median dorsal plate ; University of St. Petersburg. 

The type species, of considerable size. Anterior median dorsal 
plate longer than broad, faintly carinated, ornamented with large 
pittings, due to the complete fusion of the tubercles ; no distinct 
stellate tubercles. 

Form. Sf Loc. Devonian : N.W. Russia. 

P. 710. Imperfect anterior median dorsal plate and other fragments ; 
Prikscha, Government of Novgorod. Egerton Coll. 

P. 4600. Imperfect proximal marginal plate of appendage ; Prikscha. 

Enniskillen Coll. 

43452 a. Fragments of plates ; Prikscha. 

Presented by Kenneth Murchison, Esq., 1872. 

Bothriolepis panderi, Lahusen. 

1880. Bothriolepis pander i, J. Lahusen, Verhandl. russ.-kais. mineral. 

Gesell. [2] vol. xv. p. 125, pis. i., ii. 
1880. Bothriolepis pander i, H. Trautschold, Bull. Soc. Imp. Nat. Moscou, 

pt. ii. p. 169, pi. ii. 

PART IT. Q 



226 \NTIAECHA. 

1888. Bothriolepis panderi, R. H. Traquair, Ann. Mag. Nat. Hist. [6] 
vol. ii. p. 495. 

Type. Imperfect head and trunk ; School of Mines, St. Petersburg. 

A species scarcely smaller than the type, the head attaining a 
breadth of 0*095, and much broader than long. Anterior median 
dorsal plate almost as broad as long, faintly keeled posteriorly. 
Ornamentation consisting of large stellate tubercles usually fused 
into vermiculating ridges. 

Form. <$f Loc. Devonian : River Ssjass, Govt, of St. Petersburg. 

P. 4490, 4490 a. Articular portion of large anterior ventro-lateral 
plate, and a similar smaller fossil. Purchased, 1884. 

P. 4492. Portion of dorso-lateral plate. Purchased, 1884. 



Bothriolepis major (Agassiz). 
[Plate VI. figs. 5-8.] 

1844. Glyptosteus reticulaust, L. Agassiz, Poiss. Foss. vol. i. p. xxxiv 
(name only), in part. 

1844. Pterichthys major, L. Agassiz, Poiss. Foss. V. G. R. pp. 5, 19, 
133, pi. xxxi. figs. 1-3. 

1845. Bothriolepis oimatus, L. Agassiz (errore), ibid. pi. xxix. figs. 3-5. 
[Brit. Mus. No. 28873.] 

1845. Placothorax paradoxus, L. Agassiz, ibid. p. 134, pi. xxx. a. 

figs. 20-23. [Portions of pectoral appendages; collection of James 

Powxie, Esq.] 
1860. Asterolepis major, E. vonEichwald, Leth. Rossica, vol. i. p. loll. 
1880. Bothriolepis major, J. Lahusen, Verhandl. russ.-kais. mineral. 

Gesell. [2] vol. xv. p. 136. 
1888. Bothriolepis major, R. H. Traquair, Geol. Mag. [3] vol. v. p. 510, 

and Ann. Mag. Xat. Hist. [6] vol. ii. p. 501. 
1888. Bothriolepis giganteus, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 510, and Ann. Mag. Nat. Hist. [6] vol. ii. p. 504, pl.xviii.%. 3. 

[Brit. Mus. No. 28873.] 

Type. Proximal plates of pectoral appendage ; Geological Society 
of London. 

An imperfectly known species, of moderate or large size. Tu- 
bercles upon dermal plates nearly always confluent, though often 
displaying indications of the original stellate bases. Proximal 
segment of pectoral appendage long and slender. 

The so-called Bothriolepis giganteus is now regarded by Traquair 
(in litt.) as the adult of this species. 

Form. Sf Loc. Upper Old Red Sandstone : Elgin. Devonian : 
N.W. Russia. 



ASTEROLEPID^E. 227 

38717. External and internal cast of an imperfect cranial shield ; 

Aires, near Elgin. A plaster cast taken from the im- 
pression of the outer surface is shown, of the natural size, 
in PI. VI. fig. 5, with explanatory lettering. 

Purchased, 1864. 

35995 a. Portion of median occipital, showing characteristic sensory 
canals (PI. VI. fig. 6) ; Scat Craig. Purchased, 1861. 

35995 b. Median ventral plate ; Scat Craig. Purchased, 1861. 

35988-91. Eour proximal portions of articular bones of pectoral 
appendages ; Scat Craig. Purchased, 1861. 

P. 4719 a. Portion of anterior ventro-lateral plate, with fragments 
of the two articular bones in position ; Scat Craig. 

Purchased, 1884. 

P. 4719 b. Three imperfect dermal plates ; Scat Craig. 

Purchased, 1884. 

P. 5095. Articular portion of anterior ventro-lateral, and detached 

proximal end of articular bone of appendage ; Scat Craig. 

Presented by John Edward Lee, Esq., 1885. 

35995 c. Four plates of appendages, including the terminal; Scat 
Craig. One of the more proximal elements is shown, in 
outer view and transverse section, in PL VI. figs. 7, 7 a, 
while another, a distal marginal, is similarly represented, 
ibid. figs. 8, 8 a. Purchased, 1861. 

28873. The three type specimens of B. giganteus, Traquair, figured 

by Agassiz, under the name of Bothriolepis omatus, loc. cit. ; 
Alves, near Elgin. Fig. 3 appears to represent a portion 
of a lateral head-plate ; fig. 4, an imperfect ventro-lateral ; 
and fig. 5, an imperfect dorso-lateral. Purchased, 1854. 

28874. Six similar impressions of dermal plates, very imperfect ; 

Alves. Purchased, 1854. 

28874 a. Fragment of plate ; Alves. Purchased, 1854. 

38718. Impression of small, ridged plate ; Alves. Purchued, 1864. 

Remains of a species of Bothriolepis from the Heads of Ayr, 
originally associated with B. major by Traquair, are now regarded 
by the same author as representing a distinct species, B. leptocheirus, 
characterized by the length and slenderness of the appendages (to bo 
described in Proc. Roy. Phys. Soc. Edinb., according to Traquair 
in litt.). 

Q2 



228 ANTIARCHA. 

Bothriolepis obesa, Traquair. 
1888. Bothriolepis obesus, R. H. Traquair, Geol. Mag. [3] vol. v. p. 510. 

Type. Detached plates of trunk ; Edinburgh Museum. 

An imperfectly known species, of large size. Anterior median 
dorsal plate carinate ; posterior dorso-lateral relatively short and 
deep ; posterior ventro-lateral with relatively high ascending lamina. 
Ornamentation consisting of large, partially fused tubercles. 

Form. 4' Loc. Upper Old Eed Sandstone : Rule Water, near 
Jedburgh. 

Not represented in the Collection. 



•Bothriolepis canadensis, AVhiteaves. 

1880. Pterichthys (Bothriolepis) canadensis, J. F. Whiteaves, Anier. 

Journ. Sci. [3] vol. xx. p. 135, and Canadian Naturalist, n. s. 

vol. x. pp. 26, 28. 
1885. Bothriolepis canadensis, E. D. Cope, Amer. Nat. vol. xix. p. 290, 

woodc. 

1887. Pterichthys (Bothriolepis) canadensis, J. F. Whiteaves, Trans. 
Hoy. Soc. Canada, vol. iv. sect. iv. p. 101, pis. vi.-ix. 

1888. Bothriolepis canadensis, R. H. Traquair, Geol. Mag. [3] vol. v. 
p. 509, and Ann. Mag. Nat. Hist. [6] vol. ii. p. 496, pi. xviii. 
fig. 6. 

1889. Bothriolepis canadensis, J. F. Whiteaves, Trans. Roy. Soc. 
Canada, vol. vi. sect. iv. p. 91. 

Type. Nearly complete individual ; Geol. Survey of Canada, 
Ottawa. 

A species of moderate size, the head and trunk attaining a length 
of about 0*17. Head much broader than long, about one half as 
long as the dorsal carapace of the trunk ; trunk broadly ovate, the 
sides overhanging the narrowly ovate ventral surface. Proximal 
segment of pectoral appendages broad, but elongated ; distal segment 
relatively slender, only slightly ornamented, two thirds as long 
as the proximal segment ; outer and inner margins coarsely ser- 
rated. Anterior median dorsal plate as broad as long, more or less 
keeled in its posterior two thirds ; posterior median dorsal plate 
longitudinally keeled, the keel rising to a slight eminence near the 
posterior margin. Ornament consisting of fine rounded tubercles 
fused into nodose, vermiculating ridges ; those near the edges of the 
dorsal plates often directed mainly at right angles to the margins. 

Form. S," Loc- Upper Devonian : Scaumenac Bay, Province of 
Quebec, Canada. 



ASTEROLEIMDJTC. 22!) 

The following specimens were collected by Mr. Jex, and, unless 
otherwise stated, were obtained by purchase, through Mr. R. Damon, 

1888-89. 

P. 5458-59. Two plaster casts of head and trunk, dorsal aspect, 
the second showing nearly complete appendages. 

P. 5461. Dorsal plates of head, wanting the cover of the orbital 
opening. 

P. 5462. Head and trunk, dorsal aspect, with well-preserved ap- 
pendages. 

P. 5463. Very large crushed specimen, dorsal aspect, wanting 
posterior median dorsal plate. 

P. 5464. Smaller specimen, dorsal aspect, with imperfect appen- 
dages. 

P. 5967. Imperfect specimen, dorsal aspect, 0*115 in length, with 
left appendage. 

P. 5469. Dorsal aspect of trunk about equal in size to the last, with 
characteristic ornamentation. 

P. 5968. Imperfect head and trunk, dorsal aspect, Ol in length. 

P. 5473. Head and trunk, dorsal aspect, about 0*075 in length. 

P. 5465. Very broad trunk, dorsal aspect, in counterpart, 0*04 in 
length, with hinder head-plates and imperfect appendages. 

P. 5466. Very small similar specimen, in counterpart, the trunk 
0-025 in length. 

P. 5467-68. Scattered remains of large individual, and another 
specimen showing portions of the anterior ventro-laterai 
plates with the left appendage. 

P. 5311. Crushed specimen, somewhat broken, ventral aspect. 

Presented hy A. H. Foord, Esq., 1887. 

P. 5470. Much crushed and broken specimen, ventral aspect. 

P. 5471. Trunk and appendages, ventral aspect, in counterpart. 

P. 5472. Ventral plates of slightly smaller individual : the specimen 
seems to have been laterally compressed, thus causing the 
ventral armour to appear unusually narrow. 



230 



'..NTIARCflA. 



Bothriolepis hydrophila (Agassiz). 
[Plate VI. fig. 9.] 

1844. Pamphractus hydrophilus, L. Agassiz, Poiss. Foss. V. G. R. 
pp. 5, 21, pi. iv. tigs. 4-7. 

1844. Pamphractus andersoni, L. Agassiz, ibid. p. 21. 

1845. Homothorax jiemingii, L. Agassiz, ibid. p. 134, pi. xxxi. fig. 6. 
1848. Pterichthys hydrop>hilus, H. Miller & Sir P. Egerton, Quart. 

Journ. Geol. Soc. vol. iv. pp. 312. 314. 
1859. Pamphractus andersoni = Ptericlithys hydrophilus, J. Anderson, 

Dura Den, pp. 49, 52, pi. i. fig. 1. 
1862. Pterichthys hydrophilus, J. Powrie, Quart. Journ. Geol. Soc. 

vol. xviii. p. 435. 
1888. Bothriolepis hydropkilus, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 510, and Ann. Mag. Nat. Hist. [6] vol. ii. p. 500, pi. xviii. 

figs. 4, 5. 

Type. Imperfect individuals, dorsal aspect ; Museum of Practical 
Geology. 

A small species, the head and trunk attaining a length of about 




Bothriolepis hydrophila (Ag.). — Dorsal aspect, restored by E. H. Traquair. 
a., anconeal ; a. m.d., anterior median dorsal; a.d.l., anterior dorso-lateral; 
ar., articular; m., marginal; p.dd., posterior dorso-lateral; p.m.d., pos- 
terior median dorsal. 

0-08-0-09. Form of head, trunk, and dorsal plates as in B. cana- 
densis. Proximal segment of pectoral appendages broad, but elon- 



ASTEROLEPID-E. 231 

gated, the outer margin with verj' large denticulations ; distal 
segment relatively slender, only slightly ornamented, about half as 
long as the proximal segment. Ornament consisting of verini- 
culate anastomosing ridges, rarely distinctly nodose. 

A restoration of the dorsal aspect of this species is given in the 
accompanying woodcut, fig. 35. 

Form. Sf Loc. Upper Old Eed Sandstone : Dura Den, Fifeshire. 

26121. Small slab with three individuals, imperfectly preserved, 
ventral aspect. Purchased, 1851. 

26121 a. Displaced anterior ventro-lateral plates, with bases of 
appendages, ventral aspect. The elements of the left 
side are shown, of the natural size, in PI. VI. fig. 9 : a 
portion of the bone is here broken away, displaying the 
transverse ridge (r) on the inner side of the anterior 
ventro-lateral, and showing no suture in this position. 

Purchased, 1851. 



Bothriolepis macrocephala (Egerton). 

18G2. Pterichthys macrocephalus, Sir P. Egerton, Quart. Jo urn. Geol. 

Soc. vol. xviii. p. 103, pi. iii. figs. 7-9, woodc. figs. 1-3. 
1888. Bothriolepis macrocephalus, R. H. Traquair, Geol. Mag. [3j vol. v. 

p. 510, and Ann. Mag. Nat. Hist. [6] vol. ii. p. 501. 

Type. Imperfect individuals, dorsal and ventral aspect ; British 
Museum. 

A variety or species, so far as known, merely differing from the 
typical B. hydrophila in its much smaller size, the trunk only 
attaining an extreme length of 0'02. 
' Form. &f Loc. Upper Old Red Sandstone : Farlow, Shropshire. 

P. 606. First of the type specimens, dorsal aspect, figured by 
Egerton, loc. cit. fig. 7 ; Church Quarry, Farlow. 

Egerton Coll. 

36442. Second type specimen, ventral aspect, wanting the head, 
figured loc. cit. fig. 8. Purchased, 1862. 

P. 195. Third type specimen, being an impression of the anterior 
ventro-lateral plates, with part of one appendage, figured 
loc. cit. fig. 9. Weaver- Jones Coll. 

P. 4599.. Impression of anterior median dorsal plate. 

Enniskillen Coll. 



232 ANTTAKCITA. 

36483. Ventral aspect of trunk and right appendage. 

Purchased. 1862. 

36464. Anterior ventrolaterals and imperfect appendages. 

Presented by G. E. Roberts, Esq., 1862. 

P. 196. Trunk and appendages, ventral aspect. Weaver- Jones Coll. 

P. 197. Three portions of ventral plates, one being in counterpart. 

Weaver-Jones Coll. 

The two species mentioned below are founded upon anterior 
median dorsal plates, of which there are no examples in the Collec- 
tion . The type specimens are preserved in the Museum of Columbia 
College, New York. 

Bothriolepis leidyi, J. S. Newberry, Palaeoz. Fishes N. America 
(Mon. U.S. Geol. Surv. no. xvi. 1889), p. Ill, pi. xviii. 
fig. 2, pi. xx. figs. 1-5 : Stenacantlvus nitidus, J. Leidy, 
Proc. Acad. Nat. Sci. Philad. vol. viii. 1857, p. 11, and Journ. 
Acad. Nat. Sci. Philad. [2] vol. iii. (1856), p. 164, pi. xvi. 
hgs. 7, 8. [Type of Stenacanthus, founded upon portion 
of pectoral appendage in Mus. Acad. Nat. Sci. Philad.] 
Holoptychius americanus, J. Leidy (in part, errore), ibid. 
1856, p. 163, pi. xvii. fig. 4. — Catskill Group (Upper 
Devonian) ; Tioga Co., Pennsylvania. 

Bothriolepis minor, J. S. Newberry, op. cit. (1889), p. 112, pi. xx. 
figs. 6-8. — Chemung Group (Upper Devonian) ; Brad- 
ford Co., Pennsylvania. 

In the singular groups of detached plates of Bothriolepis leidyi, 
the large anterior median dorsal plate is more numerous than any 
of the others. This reminds the English palaeontologist of the 
manner in which the shields of Pteraspis sometimes occur in groups 
in the Cornstones of Herefordshire — one group comprising all dor- 
sals, another all ventrals. The last-named circumstance has some- 
times been regarded as proof that the so-called " Scaphaspis " is 
not the ventral plate of Pteraspis ; but in this case, as in that of 
the American Bothriolepis,th.e arrangement of the fossils iy evidently 
due to drifting and assorting by currents of water during the depo- 
sition of the sediment. 



CERASPIDJE. 233 

Family CERASPID.E. 

An imperfectly definable family, of uncertain position, known 
only by the detached dermal plates ; these plates consisting of a 
very thick middle layer of cancellous tissue, an inner squamous 
layer, and a thin outer layer with a fine superficial ribbed ornament. 

Genus CERASPIS, Schluter. 
[Sitzungsb. niederrheiu. Ges. Bonn, 1887, p. 120.] 

The type and only known genus. Body deep, with a sharp 
longitudinal dorsal ridge. 

The structure of the shield suggested to Schliiter the associa- 
tion of this genus with the Pteraspidse ; but the examination of a 
large series of specimens in the Museum of Comparative Zoology, 
Cambridge, Mass., has led the present writer to refer the proble- 
matical fish to the Antiarcha. One specimen shows two much 
elevated azygous plates in direct apposition one behind the other, 
very similar in form and proportions to the median dorsal plates of 
Pterichthys rhenanus ; the posterior plate, however, is relatively 
larger, has an especially deep keel, and seems to have been pro- 
duced into a posterior horn. Another plate is very similar in form 
to a ventro-lateral of Pterichtliys ; and it may be added that, where 
thickened, the plates of the Asterolepidae have an inner cancel- 
lated structure precisely similar to that observed in the fossils now 
under discussion. 

Ceraspis carinata, Schliiter. 

1887. Ceraspis carinatus, C. Schliiter, Sitzungsb. niederrhein. Ges. 

Bonn, p. 120. 
1887. Ceraspis hayenensis, C. Schluter, ibid. p. 122. 

Type. Imperfect dermal plates ; University Museum, Bonn. 

The type species, of moderate size. The horn-like process of the 
hinder dorsal plate {carinatus) much laterally compressed, with 
smooth, flattened, longitudinal ribs, very closely arranged, some- 
times intercalated and bifurcating. Anterior median dorsal plate 
(liagenensis) much longer than broad, with a sharp longitudinal 
median keel rising to an obtuse apex behind its middle point ; the 
sides of the plate facetted and marked with fine ridges parallel to 
the outer border. 

Form. $ Loc. Middle Devonian : Eifel. 

36160. Imperfect large horn-like plate, showing the superficial 
ribbed ornament above, and the inner cancellated tissue 
towards its base ; Gerolstein, Purchased. 1861, 



234 



DIPNOI. 



Subclass IV. DIPNOI. 

Skeleton partially ossified, with numerous well-developed mem- 
brane bones. Upper mandibular arch confluent with the chondro- 
cranium ; gill-clefts feebly separated, opening into a cavity with 
external cover. Exoskeleton consisting of true bony tissue. In the 
living forms — optic nerves not decussating, bulbus arteriosus of the 
heart with series of valves, intestine with a spiral valve, and air- 
bladder lung-like. 

The dermal or membrane bones of the cranial roof in this subclass 
exhibit Jittle conformity with the arrangement almost invariably 
observed in the Teleostomi ; and it seems impossible to apply to 
them the nomenclature adopted in the case of the latter subclass. 




Dentition of extinct Dipnoi. — 1. Dipterus valenciennesi, Sedgw.&Murch. ; upper 
and lower jaws, nat. size, xx, upper dental plates ; xxx, lower dental 
plates ; g, upper dentigerous bones ; n, narial openings. 2. Ctenodus cris- 
tatus, Ag. ; upper dental plates (somewhat inaccurately drawn, the oral 
aspect being in reality concave), one-third nat. size. 3. Sagenodus in- 
&qualis, Owen ; lower dentition, one-half nat. size. 4. Paladaphus insignis, 
Van Ben. k De Kon. ; lower dentition, one-sixth nat. size. 



MPTERIDrE. 



235 



Order I. SIRENOIDEI. 

Head with well-developed dermal or membrane bones ; principal 
dentition consisting of triturating plates on the pterygoid and 
splenial elements. Dermal armour of trunk, when present, con- 
sisting of imbricating scales ; no plates. Notochord persistent. 
Paired fins archipterygial ; pelvic arch consisting of a single 
bilaterally-symmetrical cartilage. 

Synopsis of Families. 

A. Cranial roof-bones numerous. 

Jugular plates ; no marginal teeth . . Dipteeid^e (p. 235). 

Jugular plates ; marginal teeth Phaneropleurid^e (p. 246). 

No jugular plates ; no marginal teeth. Ctenodontidje (p. 250). 

B. Cranial roof-bones few. 

No jugular plates; no marginal teeth. Lepidosirenid.*: (p. 264). 



Family DIPTERID.E. 

Cranial roof-bones numerous ; no distinctly differentiated maxilla 
or premaxilla, and no marginal series of teeth above or below ; 
jugular plates present. Caudal fin heterocercal. Scales cycloid. 

The only sufficiently defined genus referable to this family is 
Dipterus. 

Genus DIPTERUS, Sedgwick & Murchison. 
[Trans. Geol. Soc. [2] vol. iii. 1828, p. 143.] 

Syn. Catopterus, L. Agassiz, Poiss. Foss. vol. ii. pt. i. 1833, p. 3. 

Polyphractus, L. Agassiz, Poiss. Foss. V. G. R. 1844, pp. 5, 29. 

Body elongate, not much laterally compressed, covered with 
enamelled cycloid scales; head depressed, snout obtuse. Dental 
plates, above and below, triangular in shape, with outwardly 
radiating ridges, tuberculated or strongly crenulated. Paired fins 
acutely lobate ; two remote dorsal fins opposed to the pelvic and 
anal fins, separated from the caudal. 

The most complete account of the skeletal anatomy of Dipterus 



2'3l\ SIREN01DEI. 

is given by C. H. Pander ] and It. H. Traquair 2 ; and all the known 
species are of small size. 

Dipterus valenciennesi, Sedgwick & Murchison. 

1828. Dipterus valenciennesii, A. Sedgwick & R. I. Murchison, Trans. 

Geol. Soc. [2] vol. iii. p. 143, pi. xvi. figs. 1-3. 
1828. Dipterus macropygopterus, Sedgwick & Murchison, ibid. p. 143, 

pi. xv. figs. 1-3. [Mus. Geological Society of London.] 
1828. Dipterus brachypygopterus, Sedgwick & Murchison, ibid. p. 143, 

pi. xvii. figs. 1-3. 
1833. Catopterus analis, L. Agassiz, Poiss. Foss. vol. ii. pt. i. p. 3. 
1835. Dipterus macrolepidotus, L. Agassiz, ibid. p. 115, pi. ii. figs. 1-3, 

pi. ii. a. figs. 1-5. 
1841. Dipterus, H. Miller, Old Red Sandstone, p. 79, pi. v. fig. 1. 
1844. Pol yphr actus platycephalus, L. Agassiz, Poiss. Foss. V. G. R. 

pp. 5, 29, pi. xxvii. fig. 1, pi. xxxi. fig. 5. [Cranial shield ; British 

Museum.] 
1844. Megalichthys priscus, L. Agassiz, Poiss. Foss. vol. i. p. xxxiv 

(name only). 
1849. Dipterus, II. Miller, Footprints of the Creator, p. 59, figs. 18-22. 
1855. Dipterus brachypygopterus, D. macropygopterus, and D. valen- 
ciennesii, F. M-Coy, Brit. Paheoz. Foss. p. 592. 
1858. Dipterus valenciennesii, C. H. Pander, Ctenodipt. devon. Syst. 

p. 6, pi. i. figs. 1-4, 8, pi. ii. figs. 1, 6, 7. 
1858. Dipterus platycephalus, C. H. Pander, ibid. p. 7, pi. i. fig. 5, pi. ii. 

figs.^2, 9, pi. iii., pi. iv. figs. 23, 27, pi. v. figs. 15-19. pi. vii. tigs. 

5, 11. 
18G1. T)ipterus, T. H. Huxley, Figs. & Descrips. Brit. Organic Remains 

(Mem. Geol. Surv.), dec. x. p. 14, fig. 10, woode. 
1871. Dipterus, A. Gunther, Phil. Trans, p. 556, pi. xxxiv. fig. 4. 
1878. Dipterus, R. II. Traquair, Ann. Mag. Nat. Hist. [5] vol. ii. p. 1, 

pi. iii. figs. 1-4. 
1888. Dipterus valenciennesii, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 507. 

Type. Imperfect fishes ; Geological Society of London. 

The type species, attaining a length of not less than 0*4. Head 
with opercular apparatus occupying somewhat more than one fifth 
of the total length; cranial shield very slightly tapering forwards, 
its maximum breadth at the occiput equalling about | its total length, 
and the snout abruptly truncated, with rounded lateral angles ; 
operculum trapezoidal, with slightly convex borders, as deep as 
broad ; tuberculations of dental plates large, well separated, laterallv/ 

1 Ueber die Ctenodipterinen des devonischen Systems, 1858, pp. 6-21, with 
plates. 

3 Ann. Mag. Nat. Hist. [5] vol. ii. (1878), pp. 1-12, pi. iii. figs. 1-4. 



DTPTER IT) -■!•:. 



23' 



compressed and pointed, the apices being inclined outwards. Fins 
with prominent, narrow, scale-like fulcra ; distance between the 
origin of the pelvic fins and the pectorals twice as great as that 
between the former and the anal ; anterior dorsal fin situated 
slightly behind the pelvic pair, very small compared with the pos- 
terior dorsal, which is much elevated, its height being greater than 

Fig:. 37. 




Dipterus valencienncsi, Sedgw. & Murch. — Cranial shield, after Pander. 

the length of its base-line ; anal fin acuminate, very deep and 
narrow, situated close to the lower lobe of the caudal. Scales thick 
and punctate, exhibiting only the concentric lines of growth. 

Form. 4' Loc. Lower Old Red Sandstone : Caithness, Orkney Isles, 
Ross-shire, Cromarty, Nairnshire, and Banffshire. 

P. 759-60. Plaster casts of two cranial bucklers, a palato-pterygoid, 
and an imperfect palate with dental plates ; the originals in 
the Hugh Miller Collection, Edinburgh. Egerton Coll. 

P. 6263. Plaster cast of palatal aspect of skull ; Caithness. The 
original is preserved in the Museum of Practical Geology, 
Jermyn St., and is described and figured by A. Giinther, 
Phil. Trans. 1871, p. 556, pi. xxxiv. fig. 4. 

Made in the Museum. 

33153, 33165, 33178. Three imperfect heads, displaying the upper 
aspect of the cranial buckler ; Thurso. Purchased, 1857. 



238 SIUENOIDEI. 

42403. Upper aspect of head, much crushed and broken ; Kil- 
minster, near Wick, Caithness. Peach Coll. 

P. 755. Large abraded cranial buckler, upper aspect, and two smaller 
imperfect examples ; Orkney. Egerton Coll. 

P. 3373 a. Imperfect cranial buckler, upper aspect, showing con- 
centric structure of the dermal plates ; Orkney. This is 
the type specimen of Pohjphractus platycephalus, Agassiz, 
op. cit. (1844) pi. xxvii. fig. 1. Ennish'dlen Coll. 

P. 546. Operculum figured as Polyphractus platycephalus by Agassiz, 
ibid. pi. xxxi. fig. 5 ; Orkney. Egerton Coll. 

33166. Anterior portion of skull, showing palatine dental plates ; 
Thurso. Purchased, 1857. 

42405. Eight palatine tooth attached to supporting bone ; Thurso. 

Peach Coll. 

42404. Mandible seen in horizontal section in hard rock ; Kil- 
minster. Peach Coll. 

36007. Imperfect fish, 0*25 in length, with portions of the pectoral 
and median fins ; Tynet Burn, Banffshire. 

Purchased, 1861. 

43270. Similar specimen, somewhat smaller, displaying large por- 
tions of both pectoral fins ; Tynet Burn. Purchased, 1871. 

20686-87, 20689-90. Four specimens showing more or less of the 
trunk and median fins ; Caithness. The fourth specimen 
exhibits the two dorsal fins and a portion of the caudal, 
well exposed, with the distally branching rays. 

Purchased, 1847. 

33149-52. Slab with portions of about six fishes, and four imperfect 
larger individuals ; Thurso. Purchased, 1857. 

33172. Remains of anterior half of fish ; Holburn Head, Thurso. 

Purchased, 1857. 

42480. Nearly complete small fish ; Banniskirk, Caithness. 

Peach Coll. 

P. 618. Small fish showing median and paired fins, figured in 3Iur- 
chison's ' Siluria/ ed. 3, p. 287, fig. 71, and by Huxley, 
loc. cit. 1861, the figure being reproduced in the accom- 
panying woodcut (fig. 38) ; Banniskirk. Egerton Coll. 



DIPTERIDJ5. 



239 




1>40 BIBENOIDEI. 

P. 756. Impression of a large crushed fish, and two portions of 
small individuals ; Caithness. Egerton Coll. 

P. 3374, P. 4597. The caudal half of two small individuals, and a 
mass of scales of a large fish ; Caithness. 

Ennisfcillen Coll. 

P. 3374 a. Incomplete small fish, probably of this species ; Orkney. 

EnnisTcillen Coll. 

19808. Small fish, either of this or the following species ; Caithness. 

Purchased, 1845. 

P. 3373. Imperfect small fish, probably of this species ; Orkney. 

Enniskillen Coll. 

P. 825. Scales, probably of this species ; Edderton, near Tain, Ross- 
shire. Egerton Coll. 

P. 1175. Remains of head and trunk, probably of this species ; 
Edderton. Egerton Coll. 

Dipterus macropterus, Traquair. 

1888. Dipterus macropterus, R. H. Traquair, Geol. Mag. [3] vol. v. 
p. 508. 

1889. Dipterus macropterus, R. H. Traquair, ibid. vol. vi. p. 97, pi. ii. 

Type. Nearly complete fish ; Edinburgh Museum. 

A species usually attaining a length of about 0-2. Eorm and pro- 
portions oi" head and trunk as in the type species. Anterior dorsal 
fin relatively very small ; posterior dorsal very large, much longer 
than high. Scales relatively thin. 

Form. Sf Loc. Lower Old Red Sandstone : Caithness. 

42473-78. Six specimens, four showing the nearly complete fish, 
the others also exhibiting several details of structure ; 
John -o '-Groats. Peach Coll. 

42479. Portion of axial skeleton and scales of a comparatively large 
fish; John-o '-Groats. Peach Coll. 

The following species, being known only by detached dental 
plates, are doubtfully of this genus : — 

Dipterus (?) serratus, Eichwald. 

1844. Ctenodus serratus, E. von Eichwald, Bull. Soc. Imp. Nat. Moscou, 
vol. xvii. p. 828. 

1845. Ctenodus keyserlingii, L. Agassiz, Poiss, Foss. V. G. R. p. 122, 
pi. xxxiii. figs. 32-35. 



DIl'TERIDJS. 24:1 

1858. Dlpterus keyserlingii, C. II. Pander, Ctenodipt. devon. Syst. 

pp. 22,25 (Ppl. vii. fig. 1). 
r860. Dlpterus serratus, E, von Eichwald, Leth. Rossica, vol. i. p. 1633. 

Type. Dental plate. 

Dental plate with numerous radiating ridges ; tuberculations 
laterally compressed, almost imbricated, the pointed apices being 
inclined outwards. 

Form. S,- Loc. Devonian : St. Petersburg, Russia. 

P. 3375. Imperfect dental plate. Enniskillen Coll. 



Dipterus (?) marginalis (Agassiz). 

1845. Ctenodus marginalis, L. Agassiz, Poiss. Foss. V. G. R. p. 123, 

pi. xxviii. a. fig. 21 (non fig. 22) \ 
1858. Dipterus marginalis, C. H. Pander, Ctenodipt. devon. Syst. p. 24, 

pi. v. figs. 10-14, pi. vii. figs. 6, 7. 
18G0. Dipterus marginalis, E. von Eichwald, Leth. Rossica, vol. i. 

p. 1537. 

Type. Dental plate. 

A smaller species than D. Jceyserlingii,, with the dental tubercula- 
tions less compressed, less imbricating, and more obtusely pointed ; 
one margin and angle of the dental plate somewhat expanded, with 
slight concentric folds. 

Form. 6f Loc. Devonian : St. Petersburg. 

P. 757. Imperfect dental plate. Egerton Coll. 



Dipterus (?) radiatus (Eichwald). 

1844. Ctenodus radiatus, E, von Eichwald, Bull. Soc. Imp. Nat. Moscou, 
vol. xvii. p. 827. 

1845. Ctenodus tcoerthii, L. Agassiz, Poiss. Foss. V, GL R. p. 123, 
pi. xxxiii. fig. 36. 

1858. Dipterus radiatus, C. H. Pander, Ctenodipt. devon. Syst. p. 22, 

pi. vii. figs. 8, 9. 
1860. Dipterus radiatus, E. von Eichwald, Leth. Rossica, vol. i. p. 1536. 

Type. Dental plate. 

Dental tuberculations somewhat laterally compressed, well sepa- 
rated, obtusely pointed, and slightly inclined outwards. 
Form. Sf Loc. Devonian : St. Petersburg. 

19594. Dental plate; Ischora. Purchased, 1845. 

1 This figure is named " Ctenodus asteriscus, Ag.," by G. G-. G-iebel, Fauna- der 
Torwelt, Fische (1848), p. 343. 

PAET II. B 



/ 



2 12 RIRENOIDEI. 

The following species have also been founded upon detached teeth, 
of which the majority may belong to this genus. They are not 
represented in the Collection. 

Dipterus (Ctenodus) flabelliformis, J. S. Newberry, Palaaoz. Fishes 

N. America (Mon. U. S. Geol. Surv. no. xvi. 1889), p. 90, 

pi. xxvii. fig. 2 1 . — Chemung Group ; Warren, Pennsylvania. 

[Columbia College, New York.] 
Dipterus glaber, C. H. Pander, Ctenodipt. devon. Syst. (]858), 

p. 29, pi. vii. fig. 10 (named Dipterus (Cheirodus?) glaber 

on plate). — Devonian ; Ssjass, Govt, of St. Petersburg. 

[School of Mines, St. Petersburg.] 
Dipterus (Ctenodus) levis, J. S. Newberry, op.cit. p. 90, pi. xxvii. 

figs. 22, 23. — Chemung Group ; Warren, Pa. [Columbia 

College, New York.] 
Dipterus {Ctenodus) minutus, J. S. Newberry, ibid. p. 91, pi. xxvii. 

fig. 26. — Chemung Conglomerate ; Warren, Pa. 
Dipterus murchisoni, C. H. Pander, op. cit. p. 23, pi. vii. figs. 2-4. 

— Devonian ; Russia. [School of Mines, St. Petersburg.] 
Dipterus (Ctenodus) nelsoni, J. S. Newberry, op. cit. p. 89, 

pi. xxvii. figs. 19, 20. — Chemung Group; Warren, Pa. 

[Columbia College, New York.] 
Dipterus parvulus, L. Agassiz, Poiss. Foss. V. G. R. (1845), p. 124, 

pi. xxviii. a. fig. 23 (Ctenodus)-, E. von Eichwald, Leth. 

Rossica, vol. i. (1860), p. 1537 : Dipterus tuberculatus, 

6. H. Pander, op. cit. p. 22, pi. v. figs. 20-22.— Devonian ; 

Russia. 
Dipterus (Ctenodus) radiatus, J. S. Newberry (non Eichwald & 

Pander), op. cit. p. 119, pi. xxvii. fig. 33. — Catskill 

Group ; Tioga Co., Pa. 
Dipterus slierwoodi, J. S. Newberry, Rep. Geol. Surv. Ohio, vol. ii. 

pt. ii. (1875), p. 61, pi. lviii. fig. 17, and op. cit. (1889), 

p. 118, pi. xxvii. fig. 3. — Catskill Group ; Tioga Co., Pa. 

[Columbia College, New York.] 
Dipterus verneuilli, C. H. Pander, op. cit. p. 21, pi. v. figs. 1-9 ; 

E. von Eichwald, Leth. Rossica, vol. i. (1860), p. 1538.— 

Devonian : Russia. [School of Mines, St. Petersburg.] 

Indeterminable scales from the Devonian of the neighbourhood of 
St. Petersburg have also been named Dipterus arenaceus, E. von 
Eichwald, Bull. Soc. Imp. Nat. Moscou, vol. xvii. (1844), p. 831, 
and ibid. vol. xix. (1846), p. 308, pi. x. figs. 31, 32, and Leth. 
Rossica, vol. i. (1860), p. 1540, pi. lvii. fig. 17. 

An undetermined and imperfectly described jaw, from the Lower 



DIl'TRRID.B. 243 

Chemung Group of Ithaca, New York State, is named Dipterus 
ithacensi?, H. S. Williams, Proo. Amer. Assoc. Adv. Sci. vol. xxx. 
(1881), p. 193. 



Genus PALffiDAPHUS, P. J. Van Beneden & L. G. 

de Koninck. 

[Bull. Acad. Roy. Belg. [2] vol. xvii. 18(34, p. 150.] 

Syn. Heliodiis, J. S. Newberry, Rep. Geol. Surv. Ohio, vol. ii. pt. ii. 
1875, p. 62. 

A provisional genus at present incapable of definition, comprising 
very large Palaeozoic Dipnoan fishes, in which the anterior portion 
of the mandible resembles in shape that of Dipterus. 

Palaedaphus insignis, Tan Beneden <fc de Koninck. 

1864. Palcedaphus insignis, P. J. Van Beneden & L. G. de Koninck, 

Bull. Acad. Roy. Belg. [2] vol. xvii. p. 143, pis. i., ii. 
1871. Palcedaphus insignis, A. Giinther, Phil. Trans, p. 557. 
1875. Palcedaphus insignis, J. S. Newberry, Rep. Geol. Surv. Ohio, 

vol. ii. pt. ii. p. 63. 
1878. Palcedaphus insignis, R. H. Traquair, Ann. Mag. Nat. Hist. [5] 

vol. ii. p. 12, pi. iii. figs. 5-7. 
1888. Palcedaphus insignis, A. Fritsch, Fauna der Gaskohle, vol. ii. 

p. 88, fig. 167. 

Type. Anterior half of mandible with dental plates ; Museum, 
University of Liege. 

The type species. Mandibular dental plates attaining a length of 
about 013, with four rounded, widely-spaced, coronal ridges, scarcely 
radiating. 

Form. § Loc. Upper Devonian : Belgium. - 

43603. Plaster cast of type specimen, shown, one sixth nat. size, 
in woodc. fig. 36 (4), p. 234 ; Huy. Purchased, 1872. 

Palaedaphus devoniensis, Van Beneden. 

1869. Palcedaphus devoniensis, P. J. Van Beneden, Bull. Acad. Roy. 

Belg. [2] vol. xxvii. p. 378, with plate. 
1875. Heliodus devoniensis, J. S. Newberry, Rep. Geol. Surv. Ohio, 

vol. ii. pt. ii. p. 63. 
1878. Palcedaphus devoniensis, R. II. Traquair, Ann. Mag. Nat. Hist. 

[5] vol. ii. p. 15. 
1888. Pala'daphus devoniensis, A. Fritsch, Fauna der Gaskohle, vol. ii. 

p. 60, fig. 168. 

b2 



1M [ BIRENOIDEI. 

Type. Left palatine dental plate ; Museum, University of Liege. 

A species apparently larger than P. insignis. Palatine dental 
plates with not less than five widely-spaced, radiating, coronal ridges, 
coarsely crenulated. 

Form, <y Loc. Upper Devonian : Belgium. 

43605. Plaster cast of type specimen. 

Presented by Prof. P. J. Van Beneden, 1872. 

Palsedaphus lesleyi (Xewberry). 

1875. Heliodus lesleyi, J. S. Newberry, Rep. Geol. Surv. Ohio, vol. ii. 

pt. ii. p. 64, pi. lviii. fig. 18. 
1889. Heliodus lesleyi, J. S. Xewberry, Palseoz. Fishes X. America 

(Mori. U.S. GeoL Surv. no. xvi.), p. 86, pi. xviii. fig. 3. 

Type. Upper dental plate ; Columbia College, Xew York. 

A species much smaller than either of the preceding, known only 
by a single example of the upper dental plate ; characterized by 
eight coarsely crenulated or tuberculated coronal ridges, symmetri- 
cally radiating, and diminishing in size anteriorly and posteriorly. 

This dental plate is regarded by Xewberry as azygous, repre- 
senting the ordinary pair of palatine plates, and is thus made the 
type of a distinct genus, Heliodus. The present writer considers 
that the specimen is a normal right or left palatine. 

Form. <y Loc. Upper Chemung Group : Xorth Pennsylvania. 

Xot represented in the Collection. 

A portion apparently of a very large dental plate, much resem- 
bling the palatine of Pcdcedaplius, is described as ArcJueonectes per- 
tusus, H. von Meyer, Paheontogr. vol. vii. (1859), p. 12, pi. ii. figs. 
1, 2. The following is the type specimen : — 

33596. Portion of dental plate with parts of four coronal ridges, 
and showing a large transversely oval foramen near the 
inner border; Devonian, Gerolstein. The specimen is 
regarded as the palatal region of a Dipnoan, wanting the 
dental plates, by A. Fritsch, Fauna der Gaskohle, vol. ii. 
(1888), p. 90, woodc. fig. 170. Purchased, 1859. 

Also probably closely allied to Paloedaphus is a Dipnoan fish from 
the Devonian of the Government of Orel, Eussia, of which the frag- 
mentary mandible was described under the name of Holodus Jcipri- 
janowi by C. H. Pander, Ctenodipt. devon. Syst. (1858), p. 38, pi. vi. 
figs. 1-14. In the original description the specimen is regarded as 
the anterior portion of the skull, and this determination is considered 



DIPTERIDJR. 245 

plausible by A. Giinther, Phil. Trans. 1871, p. 557, and A. Fritsch, 
Fauna dor Gaskohle, vol. ii. (1888), p. 91 ; its reference to the 
mandible, however, seems more probably correct, as remarked by 
R. H. Traquair, Ann. Mag. Nat. Hist. [5] vol. ii. (1878), p. 15. 
Very similar also is an imperfect mandible, from an unknown 
formation and locality, named Archceotylus igaotus, H. von Meyer, 
Palaeoutogr. vol. xi. (1864), p. 285, pi. xliv. 

Genus CONCHODUS, M'Coy. 

[Ann. Mag. Nat. Hist, [2] vol. ii. 1848, p. 312.] 

Syn. Cheirodus, C. H. Pander (non M'Coy), Ctenodipt. devon. Syst. 
1858, p. 33. 

A provisional genus comprising species of small size, known only 
by the detached dental plates. Dental plates broad, thin, irregularly 
triangular, almost or quite smooth, with few short radiating ridges 
at tho outer border. 

Two species of this genus are recognized, but neither is repre- 
sented in the Collection : — 

Conclioclus jerofejewi, C. H. Pander, Ctenodipt. devon. Syst. (1858), 
p. 61, pi. vi. figs. 15-22 (Cheirodus) : Ceratodus lateralis, 
E. von Eichwald, Bull. Soc. Imp. Nat. Moscou, vol. xix. 
(1846), pt. ii. p. 299 (name ouly) : Cheirodus lateralis, 
E. von Eichwald, Leth. Rossica, vol. i. (1860), p. 1542.— 
Devonian; N.W. Russia. [School of Mines, St. Petersburg.] 
Conchodus ostreceformis, F. M'Coy, Ann. Mag. Nat. Hist. [2] 
vol. ii. (1848), p. 312, and Brit. PaLeoz. Foss. (1855), 
p. 593, pi. ii. c. fig. 7. — Upper Old Red Sandstone ; Scat 
Craig, Elgin. [The type species, founded upon a dental 
plate in the Woodwardian Museum, Cambridge.] 

Genus GANORHYNCHUS, Traquair. 
[Geol. Mag. vol. x. 1873, p. 555.] 

A provisional genus at present incapable of definition, comprising 
large Palaeozoic Dipnoan fishes in which the extremity of the snout 
(as also presumably all the external head-bones) is enveloped in a 
thick layer of punctate ganoine. 

Ganorhynchus woodward!, Traquair. 

1873. Ganorhynchus ivoodwardi, Pt. II. Traquair, Geol. Mag vol. x, 
p. ooo, pi. xiv. 

Type. Extremity of snout ; British Museum. 



246 SIRENOIDEI. 

The fcjpe species. Breadth of snout at anterior nares about 0*06 ; 
tlie inferior overturned margin very broad mesially, deeply notched 
by the narial openings laterally, flat, with few very coarse puncta- 
tions, and large tubercles upon its posterior edge. 

Form. $ Lot. Unknown. 

44627. Type specimen, incidentally mentioned under the name of 
Megalichihys hibberti by Agassiz, Poiss. Foss. vol. ii.pt. ii. 
p. 91. History unknown. 

A smaller rostrum than the type specimen of G. woodwardi, with 
a narrower inferior overturned margin and without lateral narial 
excavations, is described as GanorJiynchus beecheri, J. S. jNewberry, 
Palasoz. Fishes IS". America (Hon. U.S. Geol. Surv. no. xvi. 1889), 
p. 95, pi. xix. fig. 2. This fossil was obtained from the Chemung 
Group (Upper Devonian) of Warren, Pennsylvania, and is now in 
the Museum of Columbia College, Xew York. 

The following genera and species are also regarded by A. Fritsch 
as founded upon the dermal head-bones of Dipnoan fishes : — 

Gompholepis panderi, J. Barrande, Syst. Silur. Boheme, vol. i. 
suppl. i. (1872), p. 644, pi. xxviii. figs. 1-3 ; A. Fritsch, Fauna der 
Gaskohle, vol. ii. (1888), p. 87, fig. 166, woodc. — Upper Silurian 
(Stage 6 g 1); Chotec, Bohemia. [Royal Bohemian ^Museum, 
Prague.] 

Dipnoites perneri, A. Fritsch, Fauna der Gaskohle, vol. ii. (1888), 
p. 86, fig. 1$3, woodc. — Upper Silurian (Stage G g 3) ; Hlubocep, 
near Prague. [Royal Bohemian Museum.] 



Family PHANEROPLEURIDJE. 

Cranial roof-bones numerous ; margin of mouth, above and below, 
provided with a series of conical teeth ; jugular plates present. 
Caudal fin diphycercal. Scales cycloid. 

Synopsis of Genera. 

Ajoal fin separate Tlianeropleuron (p. 247 ). 

Anal fin continuous with caudal Uronemus 1 (p. 249). 

1 Since these pages were in type, Dr. K. H. Traquair (Proc. Eoy. Soc. Ecliob. 
vol. xvii. 1890, p. 393) has expressed his opinion that Uronemus represents a 
distinct family, the Uronemidse. The upper dental plates are stated to be 
replaced by mere granulations, but no details are as yet forthcoming. 



I'nANEROPLKUlUD.K 247 

Genus PHANEROPLEURON, Huxley. 
[In Anderson's Dura Don, 1859, p. 67.] 

Body laterally compressed, covered with very thin scales of mode- 
rate size ; snout acute. Marginal teeth conical ; dental plates with 
ridges of well-separated conical tubercles. Paired tins acutely 
lobate ; dorsal tin single, arising in advance of the pelvic pair and 
continuous with the caudal ; anal fin small, separate. 

Phaneropleuron andersoni, Huxley. 

1859. Phaneropleuron andersoni, T. H. Huxley, in J. Anderson's Dura 

Den, p. G7, pis. v., vi. 
1861. Phaneropleuron andersoni, T. H. Huxley, Figs. & Descrips. Brit. 

Organic Remains (Mem. Geol. Surv.), dec. x. p. 47, pi. iii. 
18G2. Phaneropleuron, J. Powrie, Quart. Journ. Geol. Soc. vol. xviii. 

p. 434. 
1872. Phaneropleuron andersoni, R. H. Traquair, Journ. Roy. Geol. Soc 

Ireland, n. s. vol. iii. p. 44, woodc. 

Type. Nearly complete fish ; British Museum. 

The type species, attaining a length of at least 0-35. Trunk 
narrow and elongated, more than four times as long as the head 
with the opercular apparatus ; tail produced and acutely pointed. 
Marginal teeth high and conical. Scales very thin, marked with 
delicate, granulated, radiating striae. 

Form, fy Loc. Upper Old Red Sandstone : Dura Den, Fifeshire, 



Fig. 39. 




Phaneropleuron andersoni, Huxl. — Eestored outline, by R. H. Traqwair. 

26120. A slab of yellow sandstone with remains of several indi- 
viduals of Holoplycliius flemingi and Phaneroplevron 
andersoni, including the type specimen of the latter, de- 
scribed and figured in Anderson's ' Dura Den,' pi. vi. fig. 2, 
and in the Mem. Geol. Surv. dec. x. pi. iii. fig. 1. One 
fish exhibits the conical marginal teeth, another apparently 



248 SIRENOIDET. 

the edge of a palatine dental plate, and another (as already- 
noted by Huxley and Traquair) distinct jugular plates 
between the mandibular rami. Purchased, 1851. 

26117 fiu Large imperfect fish, figured by Huxley, Mem. Geol. Surv. 
dec. xiii. pi. iii. fig. 5. Purchased, 1851. 

26117. Slab with imperfect remains of two individuals. Of one 
specimen the caudal region is figured by Huxley, Mem. 
Geol. Survey, dec. xiii. pi. iii. fig. 3 ; of the other specimen 
the pelvic fin is noticed, ibid. p. 48. Purchased, 1851. 

24839. Imperfect large fish, showing axial skeleton. 

Purchased, 1850. 

P. 704, P. 2076. Fragment of abdominal region of a large fish, and 
a slab with remains of three individuals, associated with 
Holoptychius jlemingi. Egerton Coll. 

Phaneropleuron curtum, Whiteaves. 

1880. Phaneropleuron curtum, J. F. Whiteaves, Canadian ISat. n. s. 

vol. x. p. 29. 
1887. Phaneropleuron curtum, J. F. "Whiteaves, Trans. Roy. Soc. 

Canada, vol. iv. sect. iv. p. 108, pi. x. fig. 2. 

1889. Phaneropleuron curtum, J. F, Whiteaves, ibid. vol. vi. sect, iv 
p. 91, pi. v. fig. 3, pi. x. fig. 1. 

1890. Phaneropleuron curtum, O. Jaekel, Sitzungsb. Ges. naturf. 
Freunde, p. 2, woodcut of upper dental plate. 

Type. Nearly complete fish ; Geological Survey of Canada. 
Ottawa. 

Trunk scarcely more than twice as long as deep, less than four 
times as long as the head with the opercular apparatus ; tail acutely 
pointed. Scales thicker than in the type species. 

Form. <$f Log. Upper Devonian : Scaumenac Bay, P.Q., Canada. 

P. 5485-6. Imperfect fish, 0-215 in length, preserved in counter- 
part. Purchased, 1888. 

P. 5487. Imperfect fish, - 2 in length, displaying some of the head- 
bones and impressions of teeth, but wanting the paired 
fins. Purchased, 1888. 

P. 5488. Trunk of a very small individual. Purchased, 1888. 

The specimen mentioned below is not generic-ally determinable, 
but may be referred to Phaneropleuron with much probability of 
correctness. 



PHANEROPLEURID.K. 249 

P. 198. Impression of small dental plate with five coarsely tuber- 
culated, radiating ridges ; Upper Old Red Sandstone, 
Parlow, Shropshire. Weaver- Jones Coll. 



Genus URONEMUS, Agassiz. 
[Poiss. Poss. vol. ii. pt. ii. 1844, p. 178.] 
Syn. Oanopristodus, Geol. Mag. [2] vol. viii. 1881, p. 37. 

Body somewhat laterally compressed, covered with very thin 
scales of moderate size. Notochord persistent. Marginal teeth 
laterally compressed ; dental plates with series of well-separated, 
conical tubercles. Paired fins acutely lobate ; dorsal fin single, 
arising in advance of the pelvic pair, continuous with the caudal ; 
no separate anal fin. 



Uronemus lobatus, Traquair. 

1844. Uronemus lobatus, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. p. 178 

(undefined). 
1871. Phaneropleuron elegans, R. H. Traquair, Geol. Mag. vol. viii. 

p. 534. [Name subsequently withdrawn.] 
1873. Uronemus lobatus, R. H. Traquair, Journ. Roy. Geol. Soc. 

Ireland, n. s. vol. hi. p. 41, pi. v. 

Type. Imperfect fish ; British Museum. 

The type species, of small size, attaining a maximum length of 
about 0'2. Trunk narrow and elongated, at least five times as 
long as the head with the opercular apparatus ; tail produced and 
acutely pointed. Marginal teeth in the form of low, laterally 
compressed, smooth-edged cones, confluent at their bases and 
brilliantly ganoid. Dorsal fin arising a very short distance behind 
the head. Scales very thin, marked with faint longitudinal or 
radiating striae. 

Form, fy Loc. Calciferous Sandstones : Burdiehouse, near Edin- 
burgh. 

P. 2273. Caudal region and posterior portion of the abdominal 
region, being the type specimen noticed by Traquair, 1873. 

Egerton Coll. 

P. 3276. Imperfect fish, described by Traquair, ibid. p. 47. 

Ennishillen ColL 



250 



SIEE^OIDEI. 



Uronemus splendens, Traquair. 
[Plate IV. fig. 5.] 

1881. Ganopristodus splendens, R. II. Traquair, Geol. Mag. [2] vol. viii. 
p. 37. 

1882. Ganopristodus splendens, R. II. Traquair, ibid. vol. ix. p. 543. 
1890. Uronemus splendens, R. H. Traquair, ibid. [3] vol. vii. p. 252. 

Type. Jaws ; collection of Dr. R. H. Traquair. 

A species of somewhat larger size than the type ; head and 
opercular apparatus occupying at least one quarter of the total 
length. Marginal teeth sometimes in part serrated, otherwise as in 
the type species. Scales oval, sometimes truncated, dull and smooth. 

This is the type species of the so-called Ganopristodus. 

Form, fy Loc. Middle Carboniferous Limestone (Blackband Iron- 
stone) : Borough Lee, near Edinburgh, 

P. 5986. Fragment of mandible with teeth, partly shown, of the 
natural size, in PI. IV. fig. 5. Purchased, 1889. 



Family CTENODONTJD^E. 

Cranial roof-bones numerous ; no distinctly differentiated max- 
illa or premaxilla, and no marginal series of teeth above or below ; 
jugular plates absent. Caudal fin diphycercal. Scales more or less 
cycloid. 

Synopsis of Genera. 
One median occipital plate ; dental plates with 

numerous ridges Ctenodus (p. 250). 

Two median occipital plates ; dental plates with 

fewer ridges Sagenodus (p. 255). 

Genus CTENODUS, Agassiz. 

[Poiss. Foss. vol. iii. 183S, p. 137.] 

Syn. (?) Campy lopleuron, T. H. Huxley & E. P. Wright, Trans. Roy, 
Irish Acad. vol. xxiv. 18G7, p. 353. 

Body depressed, covered with large thin scales, almost quadrate 
in shape, but having the angles well rounded ; both scales and 
external bones destitute of a ganoine-layer. A single median 
occipital plate, with a pair of plates immediately adjoining in front. 
Dental plates, above and below, triangular, irregularly ovate, or 



ctbxodontidje. 251 

elliptical in form, with numerous strong, outwardly directed ridges, 
tuberculated or crenulated. Dorsal and anal tins continuous with 
the caudal. 

The remains of this genus and of the closely allied Sa- 
genodus (p. 2oo) are usually very fragmentary, and the paired 
fins still remain unknown. The so-called Campylopleuron shows 
the form of the tail ; but the only tolerably complete individuals 
hitherto discovered ' are too imperfectly preserved for satisfactory 
discussion. A general review of the principal skeletal features 
already discovered is given by W. J. Barkas 2 , Miall ', and 
Fritsch \ Cranial roof-bones are also discussed and figured 
by Hancock and Atthey 5 and T. P. Barkas 6 ; the palate is 
described by Miall 7 , Hancock and Atthey 8 , and T. P. Barkas 9 ; 
the mandible by Atthey 10 ; and the teeth especially by Hancock 
and Atthey " and W. J. Barkas VJ . The scales are first described and 
figured by Hancock and Atthey 13 . 

Ctenodus cristatus, Agassiz. 

[Plate IY. fig. 1.] 

1826. " Palate," J. De C. Sowerby, Zool. Journ. vol. ii. p. 23, pi. ii. fig. 2. 
1838. Ctenodus cristatus, L. Agassiz, Poiss. Foss. vol. hi. p. 137, pi. xix. 

fig. 16. 
1868. Ctenodus cristatus, T. Atthey, Ann. Mag. Nat. Hist. [4] vol. i. 

p. 83. 
18G8. Ctenodus tubercidatus, T. Atthey, ibid. p. 83. [Lower dental 

plates ; Newcastle-on-Tyne Museum.] 

1 Hancock & Atthey, Nat. Hist. Trans. Northurnb. & Durham, vol. iii. p. 55 ; 
A. Fritsch, Fauna der Gaskohle, &c, Bohmens, toI. ii. p. 93, pi. lxxx. b. 

2 Proc. Roy. Soc. N. S. Wales, vol. x. (1877), pp. 99-123, and ibid. vol. xi. 
(1878), pp. 51-64. 

3 L. 0. Miall, " On some Bones of Ctenodus" Proc. Yorksh. Geol. & Polyt. 
Soc. n. s. vol. vii. 1880, pp. 289-299, with figs. 

4 A. Fritsch, Fauna der Gaskohle, &c, Bohmens, vol. ii. pt. 3 (1888). 

5 Nat. Hist. Trans. Northurnb. & Durham, vol. iv. p. 401. 

6 Coal Meas. Palseont. 1873, p. 113, figs. 244-246. 

7 Quart. Journ. Geol. Soc. vol.xxx. (1874), p. 772, pi. xlvii. 

8 Nat. Hist. Trans. Northurnb. & Durham, vol. iv. p. 399, pi. xiv. 

9 Coal Meas. Palseont. p. 114, fig. 247. 

10 Nat. Hist. Trans. Northurnb. & Durham, vol. v. p. 227, pi. v. figs. 1, 2. 

11 Ibid. vol. iii. p. 61 (dental plate). 

* 2 Proc. Roy. Soc. N. S. Wales, vol. x. (1877), pp. 99-109, with figs, 
(palatine dental plates) ; ibid. p. 115 (vomerine teeth). See also T. Atthey, 
Nat. Hist. Trans. Northurnb. & Durham, vol. v. (1875), p. 228, pi. v. fig. 4 
(vomerine teeth). 

13 Nat. Hist. Trans. Northurnb. & Durham, vol. iii. p. 55 ; and loc. cit. vol. iv. 
p. 398, pi. xiii. fig. 3, p. 417, pi. xvi. 



2o2 SIKEN01DEI. 

18(50. Ctenodus tuberculatus, T. P. Barkas & II. Woodward, Geol. 
Mag. vol. vi. p. 317, pi. ix. 

1869. Ctenodus ovatus, T. P. Barkas, Scientific Opinion, vol. ii. p. 557. 
[Upper dental plate ; collection of T. P. Barkas, Esq.] 

1870. Ctenodus cristatus, Hancock & Atthey, Nat. Hist. Trans. North- 
umb. & Durham, vol. iii. pp. 61, 92. 

1870. Ctenodus tuberculatus, Hancock & Atthey, ibid. p. 61. 

1872. Ctenodus tuberculatus, Hancock & Atthey, ibid. vol. iv. pi. xiv. 

1873. Ctenodus tuberculatus, T. P. Barkas, Coal Meas. Pakeont. p. 28, 
figs. 83, 84, 92. 

1873. Ctenodus ovatus, T. P. Barkas, ibid. p. 28, fig. 89. 

1873. Ctenodus concavus, T. P. Barkas, ibid. p. 28, fig. 88. [Abraded 
upper dental plate ; collection of T. P. Barkas, Esq.]. 

1874. Ctenodus cristatus, L. C. Miall, Quart. Journ. Geol. Soc. vol. xxx. 
p. 772, pi. xlvii. 

1875. Ctenodus cristatus, L. C. Miall, Ann. Mag. Nat. Hist. [4] vol. xv. 
p. 436. 

1875. Ctenodus cristatus, J. Ward, [Proc] N. Staffs. Nat. Field Club, 

p. 244, figs. 1, 2. 
1875. Ctenodus tuberculatus, J. Ward, ibid. p. 246. 
1877. Ctenodus cristatus, W. J. Barkas, Proc. Roy. Soc. N. S. Wales, 

vol. x. p. 102. 
1877 Ctenodus tuberculatus, W. J. Barkas, ibid. p. 104, figs. 1, 10, 11, 

23. 
1877. Ctenodus ovatus, W. J. Barkas, ibid. p. 108, fig. 8. 
1877. Ctenodus concavus, W. J. Barkas, ibid. p. 106, tig. 4. 
1888. Ctenodus cristatus, A. Fritsch, Fauna der Gaskohle, vol. ii. 

p. 77, woodc. figs. 155, 156. 
1890. Ctenodus cristatus, J. Ward, Trans. N. Staffs. Inst. Mining 

Engin. vol. x. pp. 154, 156, pi. iii. figs. 3, 4. 
1890. Ctenodus cristatus, Woodward & Sherborn, Cat. Brit. Fo^s. 

Vertebrata, p. 51 (synonymy). 

Type. Palatine dental plate ; Leeds Museum. 

The type species. Palatine dental plate broad-ovate or elliptical 
in form, attaining a length of about 0*08 and a maximum breadth 
of about 0*04 ; inner margin gibbous or gently rounded ; coronal 
surface flat or slightly concave, with 12-14 acute, prominently 
tuberculated ridges, only slightly radiated ; the tubercles laterally 
compressed. Mandibular dental plate relatively narrower and 
convex, similarly ridged. 

Form. $ Loc. Coal-Measures : England and South Scotland. 

P. 5031. Imperfect skull exhibiting the upper surface, shown, of 
two-thirds the natural size, in PL IV. fig. 1 ; Great Eow 
Coal, Clanway, North Staffordshire. The fragmentary 
remains and partial impression of a palatine dental plate 



CTENODONTID-E. 2iJ?) 

(t.) determine the anterior extremity of the specimen, and 
suggest its probable reference to C. cristatus. Nearly all 
the bones are considerably fractured on the external 
surface, and some are shown in little more than impres- 
sions ; but the approximate outlines of most of the 
elements of the cranial shield appear to be distinguishable. 
Hindermost is a large median plate (0) elongated antero- 
posterior^*, and having the anterior margin produced 
mesially into a short triangular projection between the 
posterior extremities of the narrow pair of elements (I) 
immediately in front. The last-named bones are only in 
contact in the middle line of the skull for about half their 
extent in advance of the process of the hinder mesial 
element, being soon separated by another, though com- 
paratively small and narrow, azygous bone (0) ; and this 
likewise extends between the hinder ends of a second 
larger pair (I), which would be originally in direct contact 
with the anterior ends of the first pair. . This median 
series of bones is immediately flanked by four pairs of 
large broad bones, of which the first (II) and half of the 
second adjoin the hindermost element, while the third is in 
contact with both pairs of series I., and the fourth probably 
with the anterior inner pair alone. Still more externally 
there occurs another series of broad alternating bones on 
either side (III), of which only few fragments are preserved. 
On the whole, it will be noticed that there is a remark- 
able resemblance to the arrangement of the plates in the 
cranial shield of Bipterus (fig. 37), as already recognized 
by Hancock and Atthey - ; the only striking difference 
being the apparent subdivision of some of the elements in 
the Devonian genus. Moreover, the median series of 
bones is arranged exactly as in Aeipenser and Polyodon 2 . 

Purchased, 1885. 

38857. Crushed remains of the head ; Airdrie, Lanarkshire. The 
dental plates are much abraded and imperfectly exposed ; 
a few of the posterior cranial roof-bones are distinguish- 
able ; and there are also portions of the palate, though 
broken almost beyond recognition. Purchased, 1864 

45857. Operculum ; Newsham. Purchased, 1874. 

1 Nat. Hist. Trans. Northuinb. & Durham, vol. ir. p. 401. 

2 T. W. Bridge, Phil. Trans. 1878, p. 684, pi. lv. 



254 SIRENOIDEI. 

36915. Much abraded palatine dental plate, resembling C. ovatus, 
Barkas ; Dalkeith, near Edinburgh. Purchased, 1863. 

21423. Similar dental plate, more imperfect ; Carluke, Lanark- 
shire. Purchased, 1847. 

21422. Slab with imperfect palatine dental plate, the partial 
impression of another, and fragments of bone ; Carluke. 

Purchased, 1847. 

P. 6284. Plaster cast of palatine dental plate described and figured 
in the Geol. Mag. vol. vi. p. 316, pi. ix. fig. 2 ; Low 
Main Seam, Newsham, near Newcastle-upon-Tyne. 

P. 3382-3. Imperfect palatine dental plate, and a small example of 
the mandibular dental plate associated with Sagenodus 
incequalis ; Newsham. Ennislcillen Coll. 

41121. Mandibular dental plate detached from matrix, somewhat 
crushed, and figured in the Geol. Mag. vol. vi. pi. ix. 
fig. 3 (C. tuberculatus) ; Carluke. Bruson Coll. 

45854. Imperfect left mandibular dental plate, with bone ; News- 
ham. Purchased, 1874. 

P. 774. Similar but larger specimen ; (?) Newsham. Egerton Coll. 

P. 5165. Mandibular dental plate ; Hanley, Staffordshire. 

Purchased, 1885. 

P. 5164. Portion of a larger dental plate ; Tunstall, Staffordshire. 

Purchased, 1885. 

Ctenodus interruptus, Barkas. 
1869. Ctenodus interruptus, T. P. Barkas, Scientific Opinion, vol. ii. 

p. 113. 
1890. Ctenodus interruptus, A. S.Woodward, Ann. Rep. Yorksh. Phil. 

Soc. 1889, p. 37, pi. i. fig. 2. 
1890. Ctenodus interruptus, R. H. Traquair, Geol. Mag. [3] vol. vii. 

p. 249. 

Type. Mandibular dental plate ; York Museum. 

Dental plates closely resembling those of C. cristatus, very 
variable in characters, with 12-14 ridges. Denticles very pro- 
minent and well separated in the outer moiety of the ridges, each 
much compressed in the direction of the ridge to which it pertains. 

Form. 4' Loc. Calciferous Sandstones : Fifeshire and Midlothian. 
Carboniferous Limestone: Fifeshire, Midlothian, and Ayrshire. 

Not renresented in the Collection. 



CTEN0D0NT1DJ4. 2fOO 

Ctenodus murchisoni, Ward. 

[Plate IV. fig. 4.] 

1843. Ctenodus alatus, L. Agassiz, Poiss. Foss. vol. iii. p. 174 (name 
only). 

1844. Ctenodus murchisoni, L. Agassiz, Poiss. Foss. vol. i. p. xxxv 
(name only). 

1890. Ctenodus murchisoni, J. Ward, Trans. N. Staffs. Inst. Mining 
Engin. vol. x. p. 15G. 

Type. Palatine dental plate ; British Museum. 

Palatine dental plate attaining a length of about 0*7 and a 
maximum breadth of 0*04, irregularly oval in shape ; coronal 
surface more or less concave, with about twenty small, acute, 
coarsely tuberculated ridges, scarcely radiated. 

Form. § Loc. Upper Coal-Measures (Spirorbis Limestone) : Shrop- 
shire and Lancashire. Middle Coal-Measures (Bassey Mine Iron- 
stone) : Staffordshire. 

P. 518. Type specimen labelled in Agassiz's handwriting, shown, of 
the natural size, in PI. IV. fig. 4; Leebotwood. The 
dental plate is of the left side, and the margins towards 
the anterior extremity are much broken. Egerton Coll. 

The following species has also been described : — 

Ctenodus wagneri, J. S. Xewberry, Palseoz. Fishes N. America 

(Mon. U.S. Geol. Surv. no. xvi. 1889), p. 172, pi. xxvii. 

fig. 30. — Cleveland Shale (Lower Carboniferous) ; Ohio. 

[Columbia College, New York.] 

The following species seems to be founded upon an abraded 
dental plaie of Ctenodus : — 

Conchodus plicatus, J. W. Dawson, Acadian Geol. ed. 2 (1868), 
p. 209, fig. 53. — Coal-Measures; Nova Scotia. [Eedpath 
Museum, Montreal.] 

Genus SAGENODUS, Owen. 
[Trans. Odontol. Soc. vol. v. 1867, p. 365.] 

Syn. Petalodopsis, W. J. Barkas, Monthly Rev. Dental Surgery, vol. ii. 

1874, p. 538. 
Ptyonodus, E. D. Cope, Proc. Amer. Phil. Soc. vol. xvli. 1878, 

p. 192. 
Megapleuron, A. Gaudry, Enchainements du Monde Animal, 

Foss. Primaires, 1883, p. 239. 
Hemietenodus, O. Jaekel, Sitzungsb. Ges. naturf. Freunde, 1890, 

p. 7 (in part). 



256 SIREN01DEI. 

Body depressed, covered with large thin scales, almost quadrate 
in shape, but having the angles well rounded; both scales and 
external bones destitute of a ganoine-layer. A large median 
occipital plate posteriorly, with a smaller median plate immediately 
adjoining the front margin of this element. Dental plates, above 
and below, triangular, irregularly ovate or elliptical in form, with 
few strong, outwardly directed ridges, more or less tuberculated or 
crenulated ; vomerine teeth resembling a single ridge of a dental 
plate. Dorsal and anal fins continuous with the caudal. 

The name Sagenodus was first applied bj- Owen to a horizontal 
microscopical section of a dental plate ; while that of Ptyonodus was 
given by Cope to dental plates differing only from those of Cera- 
todus in the non-punctate character of the coronal surface. The 
vomerine tooth was originally termed Petalodopsis by Barkas, on the 
erroneous supposition that it pertained to an Elasmobranch allied to 
Petalodus ; and a head with the abdominal region, mingled with 
Palaeoniscid scales, formed the type of Megapleuron, Gaudry. On 
account of the limited extent to which the ridges of the dental 
plates are tuberculated in the adult, the type species was associated 
by Jaekel, evidently in error, with a Ceratodont species from the 
Muschelkalk, and re-named Hemictenodus ; and, without any allu- 
sion to synonymy, B. H. Traquair recently 1 adopted the latter 
term, while pointing out the essential feature in the diagnosis, i. e. 
the disposition of the median occipital bones. 

Sagenodus inaequalis, Owen. 
[Plate IV. figs. 2, 3.] 

18G7. Sagenodus incequalis, B. Owen, Trans. Odontol. Soc. vol. v. 

p. 365, pi. xii. 
1868. Ctenodus obliquus, T. Atthey, Ann. Mag. Nat. Hist. [4] vol. i. 

p. 84. [Dental plate ; Newcastle-upon-Tyne Museum.] 
1868. Ctenodus elegans, T. Atthey, ibid. p. 86. [Ditto.] 
1868. Ctenodus imbricatus, T. Atthey, ibid. p. 86. [Ditto.] 
1868. Ctenodus elltpticus, T. Atthey, ibid, p. 87. [Ditto.] 
1870. Ctenodus obliquus, elegans, imbricatus, and ellipticm, Hancock St 

Atthey, Nat. Hist. Trans. Northumb. & Durham, vol. iii. pp. 63- 

66. 

1872. Ctenodus obliquus, elegans, and' imbricatus, Hancock & Atthey, 
ibid. vol. iv. p. 407, pi. xiii. figs, 1-3. 

1873. Ctenodus obliquus, T. P. Barkas, Coal Meas. Paleeont. p. 28, 
figs. 85, 90. 

1873. Ctenodus elegans, T. P. Barkas, ibid. p. 28, fig. 86. 



Geol. Mag. [3] vol. vii. (1890), p. 251. 



CTEN0D0NT1P E. 257 

1873. Ctenodus monoceros, T. P. Barkas, ibid. p. 28, fig. 87. [Dental 
plate ; collection of T. P. Barkas, Esq.] 

1873. Ctenodus quadra/its, T. P. Barkas, ' English Mechanic/ vol. xviii. 
p. 68, woodc. 1, 2. [Ditto.] 

1874-75. Petalodopsis mirabilis, W. J. Barkas, Monthly Rev. Dental 
Surgery, vol. ii. p. 538, figs, xxx.-xxxii., and ibid. vol. iii. p. 4, 
figs, xxxiii.-xxxv. [Vomerine tooth.] 

1874. Ceratodus barrandei, A. Fritsch, Sitzungsb. k. bohm. Ges. Wiss. 
p. 193 (first determined as probably referable to C. obliquus 
by L. C. Miall, Palaeont. Indica, [4] vol. i. pt. ii. 1878, p. 17). 
[Dental plates ; Royal Bohemian Museum.] 

1875. Ctenodus obliquus, T. Atthey, Ann. Mag. Nat. Hist. [4] vol. xv. 
p. 309, pi. xix. (reprinted in Nat. Hist. Trans. Northumb. & 
Durham, vol. v. 1877, p. 227, pi. v.). 

1875. Ctenodus obliquus, imbricatus, and ellipticus, J. Ward, [Proc] N. 

Staffs. Nat. Field Club, pp. 246, 247. 
1877. Ctenodus obliquus, elegans, imbricatus, ellipticus, monoceros, and 

quadratus, W. J. Barkas, Proc. Roy. Soc. N. S. Wales, vol. x. 

pp. 105-108, figs. 3, 5-7, 12, 13, 20, 21. 
1877. "Vomerine teeth of Ctenodus" W. J. Barkas, ibid. p. 115, 

figs. 14-19. 
1881. Ctenodus obliquus, L. C. Miall, Proc. Yorksh. Geol. & Polyt. Soc. 

vol. vii. p. 291, woodc. fig. 4. 
1888. Ctenodus obliquus, A. Fritsch, Fauna der Gaskohle, vol. ii. 

p. 66, pis. lxxi.-lxxix., pi. lxxx. figs. 5-12, and woodcuts. 
1890. Ctenodus obliquus, Woodward & Sherborn, Catal. Brit. Foss. 

Vertebrata, p. 52 (synonymy). 
1890. Ctenodus obliquus, J. Ward, Trans. N. Staffs. Inst. Mining Engin. 

vol. x. p. 155, pi. iii. fig. 5. 
1890. Ctenodus imbricatus, J. Ward, ibid. p. 155. 
1890. Ctenodus ellipticus, J. Ward, ibid. p. 155, pi. iii. fig. 6. 
1890. Hemictenodus obliquus ,0. Jaekel, Sitzungsb. Ges. naturf. Freunde, 

p. 7 
1890. Hemictenodus obliquus, R. H. Traquair, Geol. Mag. T3] vol. vii. 

p. 251. 

Type. Section of lower dental plate ; British Museum. 

The type species. Palatine dental plate elongated, attaining a 
length of about 0*055 and a maximum breadth of 0'025 ; outer 
margin often nearly straight, inner border regularly arched; • coronal 
surface flat or concave, with six or seven (rarely more) large, 
acute, very prominent radiating ridges, coarsely crenulated at 
the abrupt outer margin, more finely crenulated or smooth towards 
the inner margin. Mandibular dental plate only differing from the 
palatine in its comparative narrowness. 

By A. Fritsch (op. cit. 1888) the dental plates named C. elegans 
are regarded as referable to young individuals of this species ; and 

PART II. s 



258 SIRENOIDEI. 

it appears to the present writer that the so-called C. imbricatus, 
0. ellijoticus, &c, are founded upon variously abraded dental plates. 
The dental plates of the Bohemian Permian variety frequently 
exhibit one or two small posterior coronal ridges more than is 
usual in the typical form. 

Form. § Loc. Coal-Measures : Northumberland, Yorkshire, and 
Staffordshire, England ; Lanarkshire, Scotland. Lower Permian : 
Bohemia. 

45852. Hinder portion of cranial roof described and figured by T. 

P. Barkas, Coal. Meas. Palaeont. p. 113, fig. 244 ; Low 
Main Seam, Newsham, near Newcastle-upon-Tyne. 

Purchased, 1874. 

P. 3387. Imperfect bone resembling the hinder median occipital of 
the preceding specimen ; Newsham. Ennishillen Coll. 

47478. Similar bone ; Lower Permian, Kounova, Bohemia. 

Purchased, 1876. 
41632, 43497 a. Two opercula ; New sham. 

Presented by T. P. Barlcas, Esq., 1869, 1872. 

P. 3386-7. Two opercula; Newsham. Ennislcillen Coll. 

(i.) Palatine dental plates. 

45853, 45856. Palato -pterygoid with dental plate of right side; 

also a much abraded dental plate; Coal-Measures (Low 
Main Seam), Newsham, near Newcastle-upon-Tyne. 

Purchased, 1874. 

41627, 48999. Two abraded examples ; Newsham. 

Presented by T. P. Barlcas, Esq., 1869, 1876. 

P. 768. Two examples, slightly abraded ; Newsham. 

Egerton Coll. 

P. 771. Right and left palato-pterygoids with dental plates ; 
(?) Newsham. Egerton Coll. 

P. 3376, P. 3379, P. 3381. Left palato-pterygoid with dental plate ; 
also four abraded dental plates; Newsham. 

Enniskillen Coll. 

P. 5235. Abraded left dental plate ; Coal-Measures, Tividale. 

Purchased, 1886. 

39249-50. Two dental plates ; Coal-Measures, Airdrie, Lanarkshire. 

Purchased, 1865. 



CTENODONTIDiE. 259 

P. 3391. Left dental plate, with a cranial roof-bone ; Lower Per- 
mian, Kounova, Bohemia. Enniskillen Coll. 
47471. Left dental plate; Kounova. Purchased, 1876. 

(ii.) Mandibular dental plates. 
45855, 45865 a. Two specimens of the right splenial, with dental 
plate ; Newsham. Purchased and by exchange, 1874. 

43494, 49000, 49001. Three abraded examples; Newsham. 

Presented by T. P. BarTcas, Esq., 1872, 1876. 

P. 769, P. 773. Pour examples, two being extremely abraded; 
Newsham. Egerton Coll. 

P. 772. Eight splenial with dental plate ; (?) Newsham. 

Egerton Coll. 

P. 3377. Right and left splenials, with dental plates, of one 
individual; Newsham. Enniskillen Coll. 

P. 3378, P. 3380. Three specimens, left side ; Newsham. 

Enniskillen Coll. 

44145. Imperfect left dental plate ; Newsham. Purchased, 1873. 
P. 5236. Left dental plate ; Tividale. Purchased, 1886. 

P. 4588. Imperfect right splenial and dental plate, with other 
remains ; also left dental plate ; Coal-Measures, Longton,. 
Staffordshire. Enniskillen Coll. 

21423. Left dental plate, somewhat abraded and broken; Coal- 
Measures, Carluke, Lanarkshire. Purchased, 1847. 

(iii.) Dental -plates of young individuals (C. elegans). 
P. 6246. Type specimen, being a thin horizontal section of a, 
mandibular dental plate ; Newsham. 

Presented by Sir Richard Owen, K.C.B., 1890. 

41733, 45865 b. Six examples ; Newsham. 

Purchased, 1869, and by exchange, 1874.. 

P. 775. Right lower dental plate; Newsham. Egerton ColL 

P. 3381. Two examples, one shown, of twice the natural size, in 
PI. IV. fig. 2 ; Newsham. Enniskillen Coll. 

P. 3381 a. Two examples, one shown, of twice the natural size, in 
PI. IV. fig. 3 ; Longton. Enniskillen Coll. 

P. 5163. One example ; Longton. Purchased, 1885. 

s2 



260 SIRENOIDEI. 

The following specimens are specifically undetermined : — 

41851. Impression of a palatine dental plate with six or seven 
radiating ridges arranged like those of S. incequalis ; Coal- 
Measures, Jarrow Colliery, Kilkenny. 

Purchased, 1870. 

41851 a. Much abraded dental plate showing five widely-spaced 
radiating coronal ridges ; Kilkenny. Purchased, 1870. 



Sagenodus quinquecostatus, Traquair. 

1883. Ctenodus obliquus, var. quinquecostatus, R. H. Traquair, Geol. 

Mag. [2] vol. x. p. 543. 
1890. Hemictenodus quinquecostatus, R. II. Traquair, ibid. [3] vol. vii. 

p. 251. 
1890. Sagenodus quinquecostatus, R. H. Traquair, Proc. Roy. Soc. 

Edinb. vol. xvii. p. 387. 

Type. Dental plate ; collection of Dr. R. H. Traquair. 

A smaller species than the type, the dental plates having not 
more than five complete ridges. 

Imperfect skeletons of this fish are known, but not yet described. 
They are briefly noticed by Traquair, who remarks that the cranial 
roof-bones are shown to be arranged as in S. incequalis. 

Fornt. <$f Loc. Middle Carboniferous Limestone (Blackband Iron- 
stone) : Borough Lee, near Edinburgh. 

Not represented in the Collection. 

The species mentioned below have also been founded upon dental 
plates, but the distinctness of some from those recorded above still 
remains doubtful. 

Sagenodus (?) angustulus, R. H. Traquair, Geol. Mag. [2] vol. viii. 
p. 36 (Ctenodus). — Middle Carboniferous Limestone (Black- 
band Ironstone); Borough Lee, near Edinburgh. [R. H. 
Traquair Coll.] 

Sagenodus applanatus, A. Eritsch, Fauna der Gaskohle, vol. ii. 
(1888), p. 85, pi. lxxii. figs. 1-3 (Ctenodus). — Lower 
Permian ; Kounova, Bohemia. [Royal Bohemian Mus.] 

Sagenodus carbonarius, H. Romanowsky, Bull. Soc. Imp. Nat. 
Moscou, 1864, pt. ii. p. 163, pi. iv. fig. 27 (Ceratodus). — 
Lower Carboniferous ; Govt, of Toula, Russia. 

Sagenodus caudatus, W. J. Barkas, Proc. Roy. Soc. N. S. Wales, 
vol. x. (1877), p. 109, fig. 9 ( Ctenodus).— Coal-Measures ; 
Northumberland. [W. J. Barkas Coll.] 



CTENODONTID.E. 261 

Sagenodus corrugatus, T. Atthey, Ann. Mag. Nat. Hist. [4] vol. i. 
(1868), p. 84 (Ctenodus) ; Hancock & Atthey, Nat. Hist. 
Trans. Northumb. & Durham, vol. iii. (1870), p. 62 
(Ctenodus); W. J. Barkas, Proc. Hoy. Soc. N. S. Wales, 
vol. x. (1877), p. 106 (Ctenodus). — Coal-Measures ; North- 
umberland. [Newcastle-upon-Tyne Mus.] 

Sagenodus dialophus, E. D. Cope, Proc. Amer. Phil. Soc. vol. 
xvii. (1878), p. 528 (Ctenodus). — Permian; Texas. [E. 
D. Cope Collection, Philadelphia.] 

Sagenodus fossatus, E. D. Cope, Proc. Amer. Phil. Soc. vol. xvii. 
(1878), p. 53 (Ctenodus). — Permian ; East Illinois. 

Sagenodus gurleyanus, E. D. Cope, ibid. p. 54 (Ctenodus). — Per- 
mian ; East Illinois. 

Sagenodus lietei-oloplius, E. D. Cope, Proc. Acad. Nat. Sci. Philad. 
1883, p. 109 (Ctenodus). — Permian; East Illinois. 

Sagenodus obtusus, W. J. Barkas (ex T. P. Barkas), Proc. Boy. 
Soc. N. S. Wales, vol. x. (1877), p. 108 (Ctenodus).— 
Coal-Measures ; Northumberland. [T. P. Barkas Coll.] 

Sagenodus octodorsalis, T. P. Barkas, Scientific Opinion, vol. ii. 
(1869), p. 480 (Ctenodus); W. J. Barkas, Proc. Boy. 
Soc. N. S. Wales, vol. x. (1877), p. 106 (Ctenodus).— Coal- 
Measures ; Northumberland. [T. P. Barkas Coll.] 

Sagenodus paucicristatus, E. D. Cope, Proc. Amer. Phil. Soc. vol. 
xvii. (1878), p. 192 (Ptyonodus) : Ceratodus paucicris- 
tatus, E. D. Cope, ibid. p. 53. — Permian ; East Illinois. 

Sagenodus peripr ion, E. D. Cope, Proc. Amer. Phil. Soc. vol. xvii. 
(1878), p. 527 (Ctenodus). — Permian ; Texas. 

Sagenodus porrectus, E. D. Cope, ibid. p. 527 (Ctenodus). — Per- 
mian ; Texas. [E. D. Cope Collection, Philadelphia.] 

Sagenodus pusillus, E. D. Cope, Proc. Amer. Phil. Soc. vol. xvii. 
(1878), p. 191 (Ctenodus). — Permian; Vermilion Co., 
Illinois. 

Sagenodus reticulatus, J. S. Newberry, Bep. Geol. Surv. Ohio, vol. 
ii. pt. ii. (1875), p. 60 (Ctenodus). — Coal-Measures ; 
Linton, Ohio. 

Sageixodus serratus, J. S. Newberry, ibid. p. 59, pi. lviii. figs. 15, 
16 (Ctenodus), and Pakeoz. Eishes N. xlmerica (Mon. U. 
S. Geol. Surv. no. xvi. 1889), p. 226, pi. xxxvii. fig. 31 
(Ctenodus). — Coal-Measures ; Linton, Ohio. 

Sagenodus vabasensis, E. D. Cope, Proc. Acad. Nat. Sci. Philad. 
1883, p. 110 (Ctenodus), and Trans. Amer. Phil. Soc. 
vol. xvi. (1886), p. 288 (Ctenodus).— Permian ; East 
Illinois. 



262 SIRENOIDEI. 

Sagenodus vinslovi, E. D. Cope, Proc. Amer. Phil. Soc. vol. xvii. 
(1878), p. 192 (Ptyonodus) : Ceratodus vinslovii, E. D. 
Cope, Proc. Acad. Nat. Sci. Philad. 1875, p. 410.— Per- 
mian ; East Illinois. [The type species of Ptyonodus.'] 
An imperfect specimen of Sagenodus, wanting the paired fins, 
from the Lower Permian of Bohemia, is named Ctenodus tardus, 
A. Fritsch., Fauna der Gaskohle, vol. ii. (1889), p. 93, pi. lxxx b. 
[Eoyal Bohemian Museum.] 

Another head and abdominal region is named thus : — 

Megapleuron rochet, A. Gaudry, Enchainements du Monde Animal, 

Foss. Primaires (1883), p. 239, woodc. fig. 246 \— 

Permian ; Igornay, Saone-et-Loire. [Museum of Natural 

History, Paris.] 

A portion of the cranium of a species of Sagenodus, from the 

Coal-Measures of Linton, Ohio, is also named Ctenodus ohioensis, E. 

D. Cope, Rep. Geol. Surv. Ohio, vol. ii. pt. ii. (1875), p. 410, 

pi. xlv. fig. 2 (erroneously assigned to an Amphibian, Leptophractus 

obsoletus, E. D. Cope, Proc. Acad. Nat. Sci. Philad. 1873, p. 341, 

and afterwards referred to Ctenodus, E. D. Cope, ibid. 1874, p. 91) ; 

J. S. Newberry, Palseoz. Fishes N. America (Mon. U.S. Geol, 

Surv. no. xvi. 1889), p. 226, woodc. fig. 3. With this may probably 

be correlated the teeth described as Ctenodus serratus, or perhaps 

C. reticulatus. 

The scales described as follows are also probably referable to 
Sagenodus : — 

Ctenodus trachylepis, A. Fritsch, Fauna der Gaskohle, vol. ii. 

(1888), p. 85, pi. lxxx. figs. 1-4.— Lower Permiau; Nyran, 

Bohemia. [Royal Bohemian Museum.] 
Rhizodus quadratus, J. S. Newberry, Rep. Geol. Surv. Ohio, vol. i. 

pt. ii. (1873), p. 343, pi. xxxix. fig. 8.— Coal-Measures ; 

Linton, Ohio. [Columbia College, New York.] 
Rhizodus reticulatus, Newberry & Worthen, Pal. Illinois, vol. iv. 

(1870), p. 349, pi. iii. figs. 9, 13, 14.— Coal-Measures ; 

Illinois. 

An undetermined tooth from the Burdiehouse Limestone, either of 
this genus or Ctenodus, is named Ctenodus robertsoni, L. Agassiz, 
Poiss. Foss. vol. iii. (1843), p. 174. 



* As remarked by A. Fritsch (Fauna der Gaskohle, vol. ii. 1888, p. 65) the 
8m all rhombic scales assigned to this supposed distinct genus are those of a 
Pabeoniscid fish mingled with the skeleton. 



CTENODONTID^. 263 

Skeleton of Ctenodus and Sagenodus. 
The portions of skeleton mentioned below do not at present admit 
of generic and specific determination. 

P. 3389. Bone of the form named squamosal by Miall (Proc. 
Torksh. Geol. & Polyt. Soc. n.s. vol. vii. p. 293, woodc. 
fig. 6) ; Low Main Seam, Newsham, near Newcastle-upon- 
Tyne. Enniskillen Coll. 

43497. Two imperfect parasphenoid bones ; Newsham. 

Presented by T. P. Barkas, Esq., 1872. 

P. 778. Parasphenoid; (?) Newsham. Egerton Coll. 

P. 3385. Two parasphenoids ; jSTewsham. Enniskillen Coll. 

P. 6265. Angular bone of mandible 1 ; Newsham. Enniskillen Coll. 

21421 a. Two imperfect ribs, one exhibiting two nodosities as if 
twice broken during life ; Carluke, Lanarkshire. 

Purchased, 1847. 

P. 3384. Three ribs ; Newsham. Enniskillen Coll, 

P. 4576. Three blocks of coal-shale with remains of the axial 
skeleton of the trunk {Campylopleuron, Huxley), very 
friable; Coal-Measures, Castlecomer, Kilkenny, Ireland. 
One specimen exhibits appearances very suggestive of a 
diphycercal tail. Enniskillen Coll. 

P. 890. A few associated ribs of a small individual of " Campylo- 
•pleuron " ; Castlecomer. Egerton Coll. 

37958. Caudal region described as Uronemus magnus, R. H. Tra- 
quair, Geol. Mag. [2] vol. i. (1874), p. 554; Coal- 
Measures (Blackband Ironstone), Airdrie, Lanarkshire. 
The specimen is referred to the Ctenodontidse by the same 
author, ibid. [3 J vol. vii. (1890) , p. 252. Purchased, 1863. 

P. 780. Bone identified as coracoid by Miall (loc. cit. p. 297, 
fig. 11) and Fritsch (op. cit. p. 82, pi. lxxii. figs. 11, 12, 
pi. lxxvii. figs. 3, 14, 15) ; (?) Newsham. Egerton Coll. 

P. 3388 Similar bone ; Newsham. Enniskillen Coll. 

46953. Scale ; Oldbury, Worcestershire. Purchased, 1876. 

1 This element of the mandible was originally identified as the articular by 
Atthey (Nat. Hiat. Trans. North umb. & Durham, vol. v. p. 227, pi. v. figs. 1, 
2), and shown to be angular by Miall (Proc. Yorksh. Geol. &_Polyt. Soc. n. s. 
vol. vii. p. 294, fig. 8). 



264 



S1REN0IDEI. 



Family LEPIDOSIRENIDyE. 

Cranial roof-bones few ; no distinctly differentiated maxilla or 
premaxilla, and no marginal series of teeth above or below ; jugular 
plates absent. Caudal fin diphycercal. Scales cycloid. 



Genus CERATODUS, Agassiz. 

[Poiss. Foss. vol. iii. 1838, p. 129.] 

Syn. Hemictenodus, 0. Jaeliel, Sitzungsb. Ges. naturf. Freunde, 1890, 
p. 7 (in part). 

Body elongate, laterally compressed, covered with very large thin 
scales, superficially calcified ; head small and depressed, snout acute. 
Notochord persistent. Dental plates above and below triangular or 
irregularly ovoid in shape, with outwardly radiating, smooth ridges 



Fig. 40. 




Ceratodics forstcri, Kaffir.. — Open mouth, showing dentition: u, narial openings ; 
x, vomerine teeth xx, palatine dental plates; xxx, mandibular dental 
plates. 

forming a series of very large processes at the external margin, which 
are sometimes feebly denticulated. Paired fins acutely lobate ; dor- 
sal fin arising about the middle of the back, both this and the anal 
fin being continuous with the caudal. 

This definition is given on the assumption that the early Mesozoic 
teeth originally named by Agassiz pertain to a fish identical in 



LEP1D0SIREN1D.E. 205 

generic characters with the so-called Ceratodus forsteri 1 of the 
Queensland rivers. The extinct species may constitute a distinct 
typo— e.g., perhaps that already named Gosfordia (p. 275); and, in 
that case, the definition just stated will only apply to the recent fish , 
for which a new generic name will be required. 

Fig. 41. 




Ceratodus forster I, Krefflt. — Recent, Queensland Rivers. 



Ceratodus latissimus, Agassiz. 

1811. " Trionyx'" J. Parkinson, Organic Remains, vol. iii. p. 2G9, 

pi. xviii. fig. 1. 
1838. Ceratodus latissimus, L. Agassiz, Poiss. Foss. vol. iii. p. 131, 

pi. xx. figs. 8, 9. 
1838. Ceratodus curvus, L. Agassiz, ibid. p. 131, pi. xx. fig. 10. 

[Dental plate ; Bristol Museum.] 
1838. Ceratodus planus, L. Agassiz, ibid. p. 132, pi. xx. figs. 6, 7. 

[Ditto.] 
1838. Ceratodus emarginatus, L. Agassiz, ibid. p. 133, pi. xx. figs. 11- 

13. [Ditto.] 
1838. Ceratodus gibbus, L. Agassiz, ibid. p. 133, pi. xx. figs. 14, 15. 

[Ditto.] 
1838. Ceratodus dcedaleus, L. Agassiz, ibid. p. 133, pi. xx. fig. 16. 
1838. Ceratodus alius, L. Agassiz, ibid. p. 134, pi. xviii. figs. 1, 2, pi. xx. 

figs. 2-5. 
1844. Ceratodus trapezoides, T. Plieninger, in Meyer & Plieninger's 

Pal. Wiirttem bergs, p. 87, pi. xii. fig. 50. [Stuttgart Museum.] 
18o0. Ceratodus anglicus, E. Bey rich, Zeitschr. deutsch. geol. Gesell. 

vol. ii. p. 159. 
1858. Ceratodus cloacinus, F. A. Quenstedt, Der Jura, p. 34, pi. ii. 

fig. 28. [Dental plate ; Tubingen University Museum.] 

1 G. Krefift, " Description of a gigantic Amphibian allied to the genus Lepido- 
siren, from the Wide-Bay District, Queensland," Proc. Zool. Soc. 1870, p. 221, 
woodc. 1-3. A. Giinther, " Description of Ceratodus, a genus of Ganoid Fishes, 
recently discovered in Rivers of Queensland, Australia," Phil. Trans. 1871, 
pp. 511-571, pis. xxx.-xlii. See also T. H. Huxley, Proc. Zool. Soc. 1876, 
pp. 24-59, with tigs. 



266 



SIRENOIDEI. 



1878. Ceratodus polymorphus, L. C. Miall, Monogr. Siren, and Crossopt. 

Ganoids (Mon. Palaeontogr. Soc), p. 28, pi. ii. figs. 1-13, pi. iii. 

figs. 1, 2, 5, pi. iv. figs. 1-11, pi. v. figs. 1, 5. 
1889. Ceratodus latissimus, A. S. Woodward, Trans. Leicester Lit. & 

Phil. Soc. n. s. pt. xi. p. 21. 

Type. Lower dental plate ; Bristol Museum. 

The type species. Dental plates robust, attaining a maximum 
length of about 0*085, usually much longer than broad, varying in 
shape from triangular to oval and oblong ; inner margin more or less 
sharply angulated ; coronal surface generally sinuous, sometimes flat, 
and deeply pitted. Denticles four in the mandibular dental plates, 
four and a rudiment or five in the palatine, the ridges being low and 
rounded, ill-defined, and not reaching the internal margin. 

A long series of figures of the dental plates of this species is 
given by Miall, op. cit. 

Form. Sf Loc. Rhaetic : Gloucestershire and Leicestershire, 
England ; Wurtemberg. 

All the following dental plates were obtained from the Rhsetic 
Section of Aust Cliff, near Bristol. The mandibular are distinguished 
from the palatine not merely by the absence of a fifth denticle, but 
also frequently by the prismatic form of the most anterior denticle, 
this being adapted to two grinding surfaces. 

^ (i.) Upper dental plates. 

P. 4438 a. Plaster casts of four specimens and two associated dental 
plates, figured by Miall, op. cit. pi. iv. figs. 1, 3, 4, 7, 8; 
originals in the Higgins Collection, Bristol Museum. 

EnnisTcillen Coll. 

P. 4438. Plaster casts of sixteen specimens ; originals in the Higgins 
Collection. Ennisleillen Coll. 

23153. Small imperfect dental plate. Purchased, 1849. 

28280. Seven examples. Purchased, 1853. 

28495, 29035. Three specimens, one having an only gently sinuous 
external margin. Purchased, 1 853-54. 

35002-4, 35007, 36387. Five specimens. Purchased, 1860, 1862. 

41287. Narrow dental plate. Purchased, 1869. 

42721. Very broad triangular dental plate. 

Presented by H. N. Moseley, Esq., 1871. 

P. 3393. Six specimens. Enniskilhn Coll. 



LEPIDOSIRENID.E. 267 

P. 5012. Dental plate in matrix. 

Presented by John Edward Lee, Esq., 1885. 

(ii.) Lower dental plates. 
P. 4438 b. Plaster casts of four specimens, figured by Miall, op. cit. 
pi. ii. figs. 1, 6, 8, pi. iii. fig. 1 ; originals in the Higgins 
Collection. EnnisJcillen Coll. 

P. 4438 c. Plaster casts of seventeen specimens ; originals in the 
Higgins Collection. Enniskillen Coll. 

23153 a, 24840. Two specimens, the first doubtfully of the lower 
jaw. Purchased, 1849-50. 

28280 a, 28495 a, 28541, 28858. Five specimens. 

Purchased, 1853-54. 

34984-5. Two specimens, one much abraded. Purchased, 1860. 

35005, 35008, 36387 a. Five specimens. Purchased, 1860, 1862. 

41287 a. Two specimens. Purchased, 1869. 

42721 a. Three dental plates. 

Presented by H. N. Moseley, Esq., 1871. 

P. 344. Dental plate in matrix, with spine of Nemacanthus. 

Purchased, 1881. 

P. 761. Sixteen dental plates and fragments, mostly mandibular. 

Egerton Coll, 

P. 3394. Eight specimens. EnnisJcillen Coll. 

Ceratodus parvus, Agassiz. 

1838. Ceratodus parvus, L. Agassiz, Poiss. Foss. vol. iii. p. 132, pi. xx. 

fig. 1. 
(?) 1838. Ceratodus obtusus, L. Agassiz ; ibid. p. 134, pi. xix. fig. 20. 

[Dental plate ; British Museum.] 
1878. Ceratodus parvus, L. C. Miall, Monogr. Siren. & Crossopt. 

Ganoids (Mon. Palaeontogr. Soc), p. 29, pi. v. figs. 3, 4, 6- 

10. 
(?) 1878. [Ceratodus obtusus], L. C. Miall, ibid. p. 30. 

Type. Imperfect dental plate ; Bristol Museum. 

A species evidently closely allied to C. latissimus, but only attain- 
ing about half the size of the latter, and with dental plates more 
constant in form. Dental plates triangular, the inner margin being 
sharply angulated opposite, or nearly opposite, the second denticle. 
Denticles usually four in the mandibular dental plates, five in the 



268 SIRENOIDEI. 

palatine, laterally compressed ; ridges often prominent, sometimes 
extending almost to the inner angulation. 

The possibility of this dental plate being the immature form of 
C. latissimus is discussed by Miall, op. cit. 

Form. 6f Loc. Ilhaetic : Gloucestershire \ 

All the following dental plates were obtained from Aust Cliff, near 
Bristol. 

(i.) Upper dental plates. 

P. 3392. Type specimen of C. obtusus, Agassiz, apparently owing the 
obtuseness of the denticles to wearing during life. 

Enniskillen Coll. 

11211. Specimen figured by Miall, op. cit. pi. v. fig. 6. 

Mantell Coll. 

P. 4438 d. Plaster cast of dental plate figured by Miall, op. cit. pi. v. 
fig. 4. Enniskillen Coll. 

P. 4438 e. Plaster casts of four dental plates. Enniskillen Coll. 

(ii.) Loiver dental plates. 

44834. Specimen with five denticles attached to bone and assigned 
to the mandible by Miall, op. cit. pi. v. fig. 3. 

Presented by Benjamin Bright, Esq., 1873. 

28858 a. Specimen figured by Miall, op. cit. pi. v. fig. 7. 

Purchased, 1854. 

P. 4438 f. Plaster cast of fragment figured by Miall, op. cit. pi. v. 
fig. 8; original in the Higgins Collection, Bristol Museum. 

Enniskillen Coll. 

As remarked by Miall {op. cit. p. 31), the so-called C. disauris, 
Agassiz (torn. cit. p. 135, pi. xix. fig. 19, " C. bicornis "), is obviously 
an abnormal dental plate. The type specimen (P. 493, Egerton 
Coll.) was obtained from the Khaetic Section of Aust Cliff, near 
Bristol, and is probably referable to C. parvus. 

Ceratodus guentheri, Marsh. 

1878. Ceratodus giintheri, 0. C. Marsh. Amer. Journ. Sci. [3] vol. xv. 
p. 76, woodc. 

Type. Upper dental plate ; Yale College Museum. 

1 Dental plates from the Upper Keuper of Tubingen, Wiirtemberg, are also 
considered to pertain to this species by F. A. Quenstedt, Handb. Petrefakt. ed. '3, 
p. 298, pi. xxiv. figs. 4-8. 



LEPID0SIRENID^3. 2 09 

Dental plates robust, attaining a length of about 0'02, irregularly 
triangular ; inner border obtusely angulated at a pointnear its middle. 
Denticles four in the mandibular dental plates, five in the palatine, 
the ridges rounded, separated by deep notches at the outer border, 
terminating abruptly and extending more than halfway to the inner 
angulation. 

Form. Sf Loc. Upper Jurassic : Colorado. 

Not represented in tho Collection. 



Ceratodus capensis, A. S. Woodward. 

1889. Ceratodus capensis, A. S. Woodward, Ann. Mag. Nat. Hist. [G] 
vol. iv. p. 243, pi. xiv. fig. 4. 

Type. Dental plate ; British Museum. 

Dental plates thin, attaining a length of not less than 0*023, 
triangular in shape ; angulation of inner margin acute and placed 
near the posterior extremity. Denticles five or six, the ridges being 
acute, well separated by deep and wide notches and valleys, extend- 
ing within a short space of the inner angulation, gradually sloping 
to a point at the outer border, and very faintly marked with coarse 
crenulations. 

Form. Sf Loc. Upper Karoo Formation (Stormberg Beds) : Orange 
Free State, South Africa. 

P. 4807. Type specimen, wanting one or perhaps two anterior denti- 
cles ; Smithfield. By exchange, 1884. 



Ceratodus phillipsi, Agassiz. 

1838. Ceratodus philippsii, L. Agassiz, Poiss. Foss. vol. iii. p. 135, 

pL xix. fig. 17. 
1877. Ceratodus phillipsi, A. Crane, Geol. Mag. [2] vol. iv. p. 211. 
1890. Ceratodus phillipsi, A. S. Woodward, Proc. Geol. Assoc, vol. xi. 

p. 292, pi. iii. fig. 5. 

Type. Dental plate; unknown. 

Dental plates thin, attaining a length of about 0*02, almost trian- 
gular in shape ; angulation of inner margin acute and placed near 
the posterior extremity. Denticles four or five (? or six), the ridges 
being sharply rounded, well separated by deep notches and valleys, 
extending nearly to the inner angulation and terminating abruptly 
at the outer border. 

Form. <$f Loc. Bathonian : Oxfordshire (Stonesfield Slate) and 
Northamptonshire (Great Oolite). 



270 8IRENOIDEI. 

Not represented in the Collection, unless the dental plate men- 
tioned below be a much abraded example from the lower jaw : — 

11164. Much abraded left lower dental plate, doubtfully ascribed to 
this species by L. C. Miall, Siren. & Crossopt. Ganoids 
(Mon. Paheontogr. Soc. 1878), p. 32, pi. v. fig. 13; one of 
a series of sixty fossils entered " from the Stonesfield Slate, 
Cornbrash, and Forest Marble." Mantell Coll. 

Ceratodus kaupi, Agassiz. 

1838. Ceratodus kaupii, L. Agassiz, Poiss. Foss. vol. iii. p. 131, pi. xviii. 

figs. 3, 4. 
1844. Ceratodus guilielmi, T. Plieninger, in Meyer & Plieninger's Pal. 

Wiirttembergs, p. 86, pi. x. figs. 7, 8, 13. [Dental plates • Stutt- 
gart Museum.] 
1844. Ceratodus palmatus, T. Plieninger, ibid. p. 87, pi. x. fig. 9. 

[Ditto.] 
1844. Ceratodus kurrii, T. Plieninger, ibid. p. 87, pi. x. figs. 10, 11. 

[Ditto.] 
1844. Ceratodus weissmanni, T. Plieninger, ibid. p. 87, pi. xi. fig. 10. 

[Ditto.] 
1850. Ceratodus kaupii, E. Beyrich, Zeitschr. deutsch. geol. Ges. vol. ii. 

p. 160, pi. vi. figs. 1, 2. 
1852. Ceratodus kaupii, F. A. Quenstedt, Handb. Petrefakt. p. 187, 

pi. xiv. fig. 12. 
1862. Ceratodus runcinaius, O. Schlumberger (err ore), Bull. Soc. geol. 

France, [2] vol. xix. p. 707, pi. xvii. 
(?) 1878. Ceratodus Icevissimus, L. C. Miall, Monogr. Siren. & Crossopt. 

Ganoids (Mon. Paleeontogr. Soc), p. 32, pi. v. fig. 2. [Dental 

plate ; British Museum.] 
1886. Ceratodus kaupi, K. A. von Zittel, Sitzungsb. k. bay. Akad. Wiss. 

niath.-phys. 01. p. 258, figs. 1-4. 

Type. Upper dental plate ; Stuttgart Museum. 

Dental plates thin, attaining a maximum length of about 0*055, 
triangular in shape ; angulation of inner margin acute and often 
mesially placed, the two moieties of this margin being usually some- 
what arched ; coronal surface gently sinuous or flat. Denticles four 
in the mandibular dental plates, five in the palatine, the ridges being 
low, sharply rounded, ending obtusely and separated by very deep 
notches at the outer margin, and extending at least halfway to the 
inner angulation. 

Form. Sf Loc. Upper Muschelkalk : Thuringia. Lettenkohle : 
Wiirtemberg. (?) Upper Keuper : Worcestershire, England. 

Except when otherwise stated, the following specimens were 
obtained from the Lettenkohle of Hoheneck, near Ludwigsburg, 
Wiirtemberg. 



LEPID0S1KENIDJE. 



271 



(i.) Upper dental plates. 
21228. Twelve specimens, some imperfect. Purchased, 1847. 

21530. Small dental plate in matrix. Purchased, 1847. 

28452. Two specimens. Purchased, 1853. 

38662. Twenty-two dental plates, some completely detached from 
the matrix. Purchased, 1864. 

P. 764, P. 766. Three specimens. Egerton Coll. 

P. 3396-7. Six specimens, one showing the inferior aspect. 

EnnisTcillen Coll. 

P. 5017. Small dental plate in matrix. 

Presented by John Edward Lee, Esq., 1885. 

46956. Type specimen of C. Icevissimus, much broken, probably of 
this species ; Upper Keuper, Eipple, Worcestershire. 

Purchased, 1876. 
(ii.) Lower dental plates. 
21228 a. Two specimens. Purchased, 1847. 

28451, 28454. Five specimens. Purchased, 1853. 

38662 a. Twenty-six specimens, one being abnormal. 

Purchased, 1864. 

40322 a. Large dental plate, showing broad prismatic first denticle. 

Purchased, 1867. 

P. 763. Seven specimens. Egerton Coll. 

P. 3399. One specimen. EnnisTcillen Coll. 

As remarked by Quenstedt (op. cit.), the so-called C. Tcurrii is 
founded upon small dental plates too much abraded for specific de- 
termination. Some of the following specimens are of a similar 
character ; but the majority exhibit four or five denticles, and they 
may probably all be regarded as immature dental plates of C. 
kaupi. 

21228 b, 21530 a. Seven very fragmentary dental plates ; Hoheneck. 

Purchased, 1847. 

28454 a. Five abraded specimens ; Hoheneck. Purchased, 1853. 

38662 b. Twenty-five abraded specimens ; Hoheneck. 

Purchased, 1864. 

28454b. Much abraded dental plate; Lettenkohle, Bibersfeld. 

Purchased, 1853. 



2/2 BIKBNOIDEI. 

Ceratodus runcinatus, Plieninger. 

3844. Ceratodus runcinatus, T. Plieninger, in Meyer & Plieninger's 

Pal. Wiirttembergs, p. 80, pi. xi. fig. 8. 
1850. Ceratodus serratus, E. Beyrick, Zeitschr. deutsch. geol. Ges. 

vol. ii. p. 163, pi. vi. figs. 3, 4. 
18-52. Ceratodus runcinatus, F. A. Quenstedt, Handb. Petrefakt. p. 187. 
1871. Ceratodus runcinatus, A. Giinther, Phil. Trans, pi. xxxi. fig. 10, 

pi. xxxiii. figs. 4-6. 
1890. Hemictenodus intermedius, 0. Jaekel, Sitzungsb. Ges. naturf. 

Freunde, pp. 4, 6, woodcut. [Dental plate • Berlin Museum.] 

Type. Lower dental plate ; Stuttgart Museum. 

Dental plates thick and robust, attaining a maximum length of 
about 0*065, triangular in shape ; angulation of inner margin acute, 
placed close to the posterior extremity. Denticles five in the man- 
dibular dental plates, five and a small or rudimentary sixth in the 
palatine, very prominent and acute, much laterally compressed, 
separated by deep notches at the outer margin, and continuous with 
ridges extending almost or quite to the inner angulation. 

Form. Sf Log. Lettenkohle : Wiirtemberg. 

All the following specimens were obtained from Hoheneck, near 
Ludwigsburg : — 

(i.) Upper dental plates. 

2845?). Specimen wanting first denticle. Purchased, 1853. 

38661. Two dental plates attached to bone, and six isolated ex- 
amples. Purchased, 1864. 

40321. Broken specimen in matrix. Purchased, 1867. 

P. 765. Fine dental plate in matrix. Egerton Coll. 

(ii.) Lower dental plates. 

21228 e. Fine specimen figured by Giinther, loc. cit. pi. xxxi. fig. 10. 

Purchased, 1847. 

21228 d. Dental plate of which microscopical sections are figured 
by Giinther, loc. cit. pi. xxxii. figs. 4-6. Purchased, 1847. 

21228 c. Four specimens. Purchased, 1847. 

28450 a. Abraded specimen. Purchased, 1853. 

38661 a. Small abraded specimen, and a large dental plate less 
abraded. Purchased, 1864. 

42846. Broken specimen in matrix. Van Breda Coll. 



LEPID0SIRENIDJ5. 273 

P. 3395. Fine dental plate and a small abraded specimen. 

Enniskillen Coll. 

28469. Very small dental plate, exhibiting only four ridges, perhaps 
pertaining to young of this species. Purchased, 1853. 



Ceratodus hislopianus, Oldham. 

1859. Ceratodus hislopianus, T. Oldham, Mem. Geol. Surv. India, vol. i. 

p. 300, pi. xiv. figs. 1-7, pi. xvi. fig. 1. 
1878. Ceratodus hislopianus, L. C. Miall, Paleeont. Indica, [4] vol. i. 

pt. ii. p. 16, pi. iv. fig. 5. 

Type. Detached dental plates ; Indian Museum, Calcutta. 

Dental plates thick and robust, much resembling those of C. 
runcinatus, but having the denticles usually less compressed and 
never more than 4-5 in number. 

Form. Sf Loc. Trias (Kota-Maleri Group) : India. 

P. 3400. Palatine and two imperfect mandibular dental plates ; 
Maleri, near Nagpur. Enniskillen Coll. 

P. 762. Imperfect mandibular dental plate. Egerton Coll. 



Ceratodus hunterianus, Oldham. 

1859. Ceratodus hunterianus, T. Oldham, Mem. Geol. Surv. India, 

vol. i. p. 303, pi. xv. figs. 1-6, pi. xvi. fig. 4. 
1878. Ceratodus hunterianus, L. O. Miall, Palseont. Indica, [4 J vol. i. 

pt. ii. p. 16, pi. iv. figs. 1-3, 6-8. 

Type. Detached dental plates ; Indian Museum, Calcutta. 

Dental plates thick and robust, scarcely distinguishable from 
those of C. hislopianus, except by the greater size and prominence 
of the foremost denticle and the frequently less pronounced character 
of the coronal ridges. 

Form. Sf Loc. Trias (Kota-Maleri Group) : India. 

P. 3401. Mandibular dental plate ; Maleri, near Nagpur. 

Enniskillen Coll. 

A large portion of the skull and mandible of a species of Cera- 
todus from the Upper Keuper of Polzberg, near Lunz, Austria, is 
noticed by D. Stur, Verhandl. k.-k. Geol. Eeichsanst. 1886, p. 381. 

The caudal region of a species from the Lettenkohle of Bavaria, 
now in the University Museum, Wiirzburg, has been described 
under the name of Coelacanthus giganteus, T. C. Winkler, Archiv. 

PART II. x 



Jfi 6IREN0IDEI. 

Mus. Teyler, vol. v. (1880), p. 141, pi. ix. See K. A. von Zittel, 
Sitzungsb. k. bay. Akad., math.-phys. CI. 1886, p. 259. 

Dental plates, said to be identical with those of the recent Cera- 
toclus forsteri 1 , occur in the superficial Alluvial Deposits of Darling 
Downs, Queensland. One of these is noticed in ' Xature,' vol. ix 
(1S74), p. 293, under the name of C. palmeri, KrefTt. The follow- 
ing is a cast of the same : — 

45868. Plaster cast of imperfect upper dental plate, having only 
three sharply compressed horns preserved; Alluvial Deposit, 
Darling Downs, Queensland. 

Presented by Dr. A. Giinther, 1872. 

The following species have also been founded upon detached 
dental plates, but there are no examples in the Collection : — 

Ceratodus arenaceus, F. A. Quenstedt, Handb. Petrefakt. 3rd edit. 

(1883), p. 296, pi. xxiv. fig. 3.— Upper Bunter ; Suldorf, 

near Magdeburg. [Tubingen University Museum.] 
Ceratodus concinnus, T. Plieninger, in Meyer & Plieninger's Pal. 

Wiirttembergs (1844), p. 85, pi. xi. fig. 9. — Keuper ; 

Stuttgart. [Stuttgart Museum.] 
Ceratodus cornutus, F. A. Quenstedt, Handb. Petrefakt. 3rd. edit. 

(1883), p. 297, pi. xxiii. fig. 39.— Upper Muschelkalk ; 

"Wilhelmsgliick. [Tubingen University Museum.] 
Ceratodus favosus, E. D. Cope, Proc. Amer. Phil. Soc. 1884, p. 28. 

— Permian ; Texas. [E. D. Cope Collection, Philadelphia.] 
Ceratodus gyjpsatus, F. A. Quenstedt, Begleitw. geogn. Specialk 

Wiirtt. Atlasbl. Hall (1880), p. 26 ; Handb. Petrefakt. 

3rd edit. (1883), p. 297, pi. xxiv. fig. 2.- Keuper ; Wiir- 

temberg. [Tubingen University Museum.] 
Ceratodus margatus, F. A. Quenstedt, Begleitw. geogn. Specialk. 

Wiirtt. Atlasbl. Hall (1880), p. 23; Handb. Petrefakt, 

3rd edit. (1883), p. 297, pi. xxiv. fig. 1.— Keuper; Wiir- 

temberg. [Tubingen University Museum.] 
Ceratodus serratus, L. Agassiz, Poiss. Foss. vol. iii. (1838), p. 135, 

pi. xix. fig. 18. — Keuper ; Aargau, Switzerland. [Identified 

with C. runcinatus by E. Beyrich, Zeitschr. deutsch. geol. 

Ges. vol. ii. (1850), p. 163.] 
Ctratodus silesiacus, F. A. Uoemer, Geol. von Oberschlesien (1870), 

p. 184, pi. xv. figs. 6, 7. — Rhaetic (Breccia); Lissau, 

Silesia. [University of Breslau.] 
Ceratodus virapa, T. Oldham, Mem. Geol. Surv. India, vol. i. 

1 C. W. De Vis, Proc. Roy. Soc. Queensland, vol. i. (1S84).. p. 40. 



LKL'IDOSIRENID.TS. - , -> 

(1859), p. 305, pi. xiv. figs. 8 12, pi. xvi. fig. 2 ; L. C. Miall, 
Palaeont. Indica, [4 J vol. i. pt. ii. (1878), p. 16, pi. iv. 
fig. 4 : Ceratodus oblongus, T. Oldham, torn. cit. p. 307, 
pi. xv. figs. 7, 8. — Kota-Maleri Beds ; Maleri, near Nagpur, 
India. [Indian Museum, Calcutta.] 

Fragments of dental plates of Ceratodus, from the Rhaetic Bone- 
bed of Wiirtemberg, are erroneously described by Plieninger (Meyer 
& Plieninger's Pal. Wiirttembergs, p. 117, pi. x. figs. 14-16) under 
the name of Psammodus porosus. 

The so-called Ceratodus heteromorphus, Agassiz (Poiss. Foss. 
vol. iii. 1838, p. 136, pi. xviii. figs. 32-34), is founded upon a 
cephalic spine of a Hybodont Selachian (supra, Part I. p. 306), a 
much abraded Ceratodont dental plate, and a very doubtful tooth 
from the Muschelkalk. This " species " must, therefore, be re- 
moved from the list, as remarked by E. Fraas, Wiirtfc. Jahresh. 
vol. xlv. (1889), p. 233. 

Two fossils from the Upper Cretaceous Fort Union Beds of Mon- 
tana, as yet not satisfactorily determined, are named Ceratodus 
eruciferm and C. hieroglyphics, E. D. Cope, Proc. Acad. Nat. Sci. 
Philad. 1876, pp. 259, 260. 

Family position uncertain. 

Genus GOSFORDIA, A. S. Woodward. 

[Foss. Fishes Hawkesbury Series, Gosford (Mem. Geoh Surv. 

N*. S. Wales, Palaaont. no. iv. 1890), p. 4.] 

Head very small ; snout pointed ; trunk elongate, though com- 
paratively deep, laterally compressed. Median fin continuous ; 
pelvic fins acutely lobate, biserially fringed. Scales very small, 
delicate, overlapping, marked by fine striae. 

Gosfordia truncata, A. S. Woodward. 
1S90. Gosfordia tritncata, A. S. Woodward, op. cit. p. 5, pi. i., pi, ii. 

figs, i, 2. 
Type. Head and abdominal region ; Geol. Surv. Museum, Sydney. 
The type and only known species, attaining a length of about 0'6. 
Maximum depth of trunk contained somewhat more than three 
times in the total length. 

Form. <Sf Loc. Lower Hawkesbury Beds (Upper Triassic) : Gosford, 
New South Wales. 

Not represented in the Collection. 

t2 



276 ARTHRODIRA. 

Genus CONCHOPOMA, Kner. 
[Sitzungsb. math.-naturw. CI. k. Akad. Wiss. vol. lvii. 1868, pt. i. 

p. 279.] 

Head relatively large and opercular apparatus robust, the oper- 
culum convex and shaped like the valve of a bivalve shell ; dental 
plates covered with irregularly arranged, stout, conical or rounded 
tubercles. Trunk elongate and laterally compressed; median fin 
continuous. Scales small, delicate, striated. 

Conchopoma gadiforme, Kner. 

1844. CcelacantJins munsteri, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. 

p. 173 (undefined). 
1868. Conchopoma gadiforme, R. Kner, Sitzungsb. math.-naturw. CI. 

k. Akad. Wiss. vol. lvii. pt. i. p. 278, pis. i.-iv. 

Type. Well-preserved fishes ; Museums of Berlin and Strassburg. 

The type and only known species, of small size. Length of head 
with opercular apparatus about equal to the maximum depth of the 
trunk, and contained about four times in the total length. 

Form. <$f Loc. Lower Permian : Rhenish Prussia. 

P. 507, P. 3336. Nodule with nearly complete fish, wanting the 

* margins of the median fin and the paired fins, intended to 

be the type specimen of Coelacanthus muensteri, Ag. ; 

Lebach. Eyerton Sf Enniskillen Colls. 



Order II. ARTHRODIRA. 

Head with well-developed dermal or membrane bones ; principal 
upper dentition on the elements of the pterygo-palatine arch. 
Dermal armour of abdominal region consisting of large plates, of 
which a dorso-lateral pair articulate by a movable ginglymoid joint 
with the occipital border of the cranial shield. Notochord per- 
sistent. Paired fins rudimentary or absent ; pelvic basipterygia [so 
far as known] consisting of a pair of sigmoidal or club-shaped carti- 



Only a single family, that of Coccosteidae, can be referred to this 
order with certainty ; but two other imperfectly known families 
(Asterosteidae and Hylostomatidse) may also be placed here with 
much probability of correctness. 



COCCOSTEID^. 277 



Family COCCOSTEIDiE. 

Cranial shield consisting of few elements : — a median occipital, 
with two pairs of bones following immediately in front, this series 
being terminated by an anterior azygous element over the ethmoidal 
region ; three lateral pairs of bones forming the sides of the shield. 
Narial openings small and anteriorly situated. Maxilla and pre- 
maxilla well developed, but toothless ; dentition, when present, con- 
sisting of conical teeth fused with the oral margin of the mandible 
and with two inner pairs of bones in the upper jaw (presumably 
palatine and vomerine). Abdominal region with a dorsal and ventral 
armature, the large dorsal plate having a deep inner longitudinal 
keel, evidently for connection with the neural arches of the endo- 
skeletal axis. 

Synopsis of Genera. 

I. Orbits forming notches in the cranial 

shield. 

A. No pineal foramen. 

Median bone over pineal region ; no 

pectoral spine Coccosteus (p. 278). 

Similar, but with pectoral spine .... Brachydirus (p. 294). 
No median bone over pineal region ; 

no pectoral spine Phlyctcsnaspis (p. 295). 

B. Pineal foramen present. 

Scutes ornamented with fused series 

of tubercles Chelyophorus (p. 299). 

Scutes smooth or faintly rugose ; 

teeth prominent Dinichthys (p. 300). 

Scutes smooth or faintly rugose ; no 

teeth in mandible Titanichthys (p. 302). 

II. Orbits completely enclosed in the cranial 

shield. 

Scutes finely and closely tubercu- 

lated ; cranial shield much arched. Macropetalichthys (p. 303), 

Scutes finely and closely tubercu- 
lated ; cranial shield nearly flat ; 
antero-lateral processes of abdomi- 
nal shield small Homosteus (p. 304). 

Scutes coarsely and sparsely tuber- 
culated ; cranial shield nearly flat ; 
antero-lateral processes of abdomi- 
nal shield enormous Heterostev.s (p. 308). 



ARTHRODIRA. 

Genus COCCOSTEUS, Agassiz. 

[Poiss. Foss. Y. G. K. 1844, p. 22.] 

Svn. Liof/nathus, J. S. dewberry, Rep. Geol. Surv. Ohio, vol. i. pt. ii. 
1878, p. 306. 

Head and trunk broad, the dorsal aspect more or less arched from 
side to side ; scutes ornamented with rounded stellate tubercles ; 
neural and haemal arches well calcified, and the caudal region des- 
titute of armour. Elements of cranial shield not fused in the 
adult, and the occipital bones constituting less than half of its 
length ; a distinct small median bone over the pineal region, not 
perforated ; orbits forming broad notches, not bounded externally ; 
sclerotic ossified ; premaxilla and maxilla distinct, and one or two 
inner pairs of dentigerous bones in the upper jaw ; mandibular 
rami suturally united at the symphysis, each bearing a short series 
of conical teeth anchylosed with the middle of its oral margin. A 
single median dorsal shield upon the trunk, with an inner longi- 
tudinal keel, and rounded or acutely pointed posteriorly ; ventral 
armour of trunk well developed, consisting of two large lateral 
plates and two small diamond-shaped median elements, the whole 
shield united with the median dorsal by two dorso-lateral and two 
truly lateral plates ; anterior dorso-lateral plate with an articulating 
eminence, but no forwardly directed process. A pair of short deep 
plates meeting in the median line immediately in advance of the 
ventral and lateral armour, evidently representing the pectoral areh. 
A single short median dorsal fin upon the anterior portion of the 
caudal region, without fin-rays, supported by a double series of 
robust, superficially ossified cartilages, equal in number to the 
apposed neural arches. 

This is the type genus of the family, and is more completely 
known than any of its allies, on account of the fine state of preser- 
vation in which its remains occur in the Lower Old Red Sandstone 
of the Xorth of Scotland. Since the researches of Agassiz, Hugh 
Miller, and Egerton, much information concerning the skeleton of 
the fish has been obtained and published by Pander 1 and Traquair '; 
and the accompanying figures and description are chiefly based upon 
the most recent memoir of the latter author. 

The cranial shield (fig. 42) is irregularly six-sided in shape, the 

1 C. H. Pander, Die Placodermen des devonischeii Systems (St. Petersburg, 
1857). 

2 R. H. Traquair, " On the Structure of Corcoztcuz dccipitns, Agassiz," Anu. 
Mag.- Nat. Hist. [GJ vol. v. (1890), pp. 125-13(5, pi. x. 



COCCOSTEID^. 279 

anterior lateral borders being notched by the orbits (o.) and the 
front border somewhat rounded. A large quadrangular median 
occipital element (m.o.), and a flanking pair of triangular exocci- 
pitals (e.o.) form the posterior and the greater part of the postero- 
lateral borders ; the median occipital tapering anteriorly somewhat 




»z. 



Outline of cranial and dorsal shield of Coccosteus decipiens, Ag., restored by 
E. H. Traquair. — a.d.l., anterior dorso-lateral : a.L, anterior lateral ; c, cen- 
tral: e., ethmoid; e.o., external occipital; ra., marginal; m.d., median dorsal ; 
m.o., median occipital ; mx„ maxillo-suborbital ; ft.,narial opening ; o., orbit ; 
p., pineal; p.d.L, posterior dorso-lateral; p.l., posterior lateral ; p.mx., pre- 
maxilla; p.o., pre-orbital ; pt.o., post-orbital; x., opei'culum (?). 

less than the exoccipitals. Immediately in front of these plates is 
a pair of central elements (c.) meeting in a wavy longitudinal suture 
at the mesial line ; while the lateral angles of the shield are formed 
bv a small pair of quadrangular marginals (m.), wedged in on each 
side between the exoccipital, central, and postorbital {pt.o.) plates. 
The last-named element is almost as small as the marginal, and 
extends partly into the upper border of the orbital notch. A pair 
of large preorbital plates (p.o.) adjoins the front margin of the 
centrals and postorbitals, forming the anterior two thirds of the 
orbital notch* with the antorbital process. These plates meet in the 
middle line of the shield only for a short space in their hinder half, 



280 ARTHROD1RA. 

being separated in front by a small narrow pineal plate (p.), which 
exhibits a deep pit on its under surface for the reception of the 
pineal body. Still further forward the shield terminates in a 
small, short, and broad ethmoidal plate («.), of which the hinder 
border meets both the preorbitals and the pineal. A large bone on 
the cheek (fig. 42, moc.) sends forward a narrow process beneath 
the eye, and is interpreted by Pander as suborbital, by Traquair as 
maxilla, probably both in part with justification. A small element 
between this and the ethmoid is named premaxilla (pmoc.) by Tra- 
quair, and seems to form the lower border of the narial opening (n.) ; 
while posterior to the so-called maxilla is a deep triangular element 
(a?.) with free hinder border, not improbably to be regarded as the 
operculum. Within the orbit traces of a delicate ossified sclerotio 
ring, apparently continuous, are sometimes observable. The chon- 
drocranium is entirely unknown, but in an allied genus, Chelyo- 
pJwrus, the parachordal cartilages are ossified, and there seem to be 
distinct exoccipitals ; while in a single example of Coccosteus from 
Gamrie there is distinct evidence of two pairs of bones on the 
palate bearing conical teeth. There is also a single bone in each 
ramus of the lower jaw, bearing conical teeth in its middle portion, 
the two rami meeting loosely and denticulated on the anterior 
margin at the symphysis ; but the supposed premaxillse and maxillae 
are toothless. 

The line of separation between the cranial and abdominal armour 
forms a prominent cleft ; and immediately in advance of the ventro- 
lateral plates of the trunk is a pair of clavicle-shaped elements, 
meeting in the middle line ventrally and termed inter-laterals 
(fig, 43, i.l.) by Traquair. An elongated, transversely arched median 
dorsal plate (fig. 42, m.d.) covers the back, and is supported upon 
the neural arches of the endoskeletal axis beneath by a longitudinal 
ridge on its attached surface. Pour flattened plates, two above and 
two below, cover the anterior part of each side of the abdominal 
region, these being termed anterior and posterior dorsolaterals 
(a.cl.l. and p.d.l.\ anterior and posterior laterals (a.l. and p.l.). 
The anterior dorso-lateral exhibits a small rounded process on its 
front margin, to constitute a firm but readily movable joint with 
the exoccipital bone of the cranial shield ; while the antero-lateral 
plate meets the inter- lateral and, with it, serves to connect the 
ventral with the lateral and dorsal armour. The ventral shield 
extends as far backward as the great dorsal plate, and consists of 
two principal pairs of elements, the anterior and posterior ventro- 
laterals (fig. 43, a.v.l. and p.v.l.), with a small, deeply-overlapped, 
diamond-shaped median ventral (m.i'.), and a somewhat larger 
anterior median ventral (a.m. v.). 



COCCOSTEID -35. 28 1 

The course of the sensory canals is well marked upon the plates 
both of the head and trunk by deep grooves, which have often been 
mistaken for sutures. They were first clearly mapped by Traquair 
as dotted lines on the accompanying figures. 

The hinder abdominal and caudal regions are destitute of armour 
(fig. 44), the only dermal calcification occurring in a narrow band 
along the lateral line (see p. 289). 

A narrow vacant space in the position of the notochord bears 
witness to its persistence, and the tail tapers apparently in a hetero- 
cercal manner. The neural and haemal arches are short, robust, 

Fig. 43. 




Outline of ventral armour of Coccosteus decipiens, Ag., restored by E. H, 
Traquair. — a.m.v., anterior median ventral ; a.v.l., anterior ventrolateral ; 
i.L, inter-lateral (? clavicle); m.v., median ventral ; p. v.L, posterior ventro- 
lateral. 

and closely arranged, fused with their respective spines, and all 
superficially calcified. There are no ribs ; but immediately behind 
the termination of the abdominal region the neural and haemal 
arches gradually become elongated for some distance, and to the 
ends of the long neurals in this part of the axis are apposed, in 
equal number, the basal cartilages of a short dorsal fin. The latter 
cartilages occur in two rows, a proximal and a distal, the elements 
all being superficially calcified and as robust as the neural spines. 
The fin itself was membranous, and is partly shown by an Orkney 
fossil (No. P. 180) mentioned below (p. 285), but still more satis- 
factorily in a single specimen in the University of Glasgow. There 
is no anal fin, and a caudal has not yet been recognized. 



2S2 



ABTHRODIRA. 



As already remarked, the pectoral arch seems to be represented 
by a large pair of dermal bones, but no appendages are observable. 
There is, however, distinct evidence of a hinder pair of limbs (see 
p. 289), and the well-developed pelvic basipterygia (fig. 44), super- 
ficially calcified, and separated in the middle line below, are often 
conspicuous. At the broad lower end these exhibit one or two 
deep pits or foramina. In each pelvic fin there is a proximal series 
of four or five short basal cartilages, and distal to these is another 
series of elongated cartilages, all robust and superficially calcified, 

Pig. 44. 




Coccosteus decipiens, Ag. ; side view, restored. 

but arranged in a manner that is not yet clearly shown : it can 
merely be determined that the fin possessed a well-developed base 
of endeskeletal elements. 

A singular thin, quadrate plate, with rounded angles and pro- 
minent concentric lines of growth, also occurs in the abdominal 
region (fig. 44) immediately behind the much elongated haemal 
arches. To the present writer it is most suggestive of an internal 
element of support occurring in the vertical septum between the 
right and left halves of some paired organ. 



Coccosteus decipiens, Agassiz. 

[Plate VII.] 

1829. " Trionyx* Sedgwick & Murchison, Trans. Geol. Soc. [2] vol. iii. 
p. 144, pi. xvi. fig. 6. 

1841. Coccosteus, H. Miller (ex Agassiz, MS.), Old Red Sandst. pi. iii. 

1842. Coccosteus latus, L. Agassiz, Rep. Brit. Assoc, p. 87 (name only). 
1842. Coccosteus cuspidatus, P. Duff (ex Agassiz, MS.), Geol. Moray, 

p. 69, pi. viii. fig. 1, 
1844. Coccosteus decipiens, L. Agassiz, Poiss. Foss. V. G. R. pp. 26 ; 

137, pi. B. figs. 2, 3, pis. vii.-x., pi. xxx. a. fig. 19. 
1844. Coccosteus oblongus, L. Agassiz, ibid. p. 28, pi. xi. figs. 1-3, 

pi. xxx. «. fig. 2. [Imperfect skeleton ; British Museum.] 



COCCOSTEJD.fi* 



283 



1844. Coccosteus cuspidatus, L. Agassiz, ibid. pp. 28, 137, pi. xxxi. 

fig-. 4. [Median dorsal plate ; Edinburgh Museum.] 
1848. Coccostens microspondylu*, F. M'Coy, Ann. Mag. Nat. Hist. [2] 

vol. ii. p. 298. [Imperfect skeleton ; Woodwardian Museum.] 
1848. Coccosteus pusillus, F. M'Coy, ibid. p. 298. [Ditto.] 
1848. Coccosteus ? triyonasjns, F. M'Coy, ibid. p. 299. [Ditto.] 
1855. Coccosteus latus, F. M'Coy, Brit. Palseoz. Foss. p. (302. 
1855. Coccosteus oblonyus, F. M'Coy, ibid. p. 603. 
1855. Coccosteus microspondylus, F. M'Coy, ibid. p. 602, pi. ii. c. fig. 4. 
1855. Coccosteus pusillus, F. M'Coy, ibid. p. 603, pi. ii. c. fig. 5. 
1855. Coccosteus ? triyonaspis, F. M'Coy, ibid. p. 603, pi. ii. c. fig. 6. 
1860. Coccosteus decipiens, Sir P. Egerton, Quart. Journ. Geql. Soc. 

vol. xvi. p. 128. 
1860. Coccosteus milleri, Sir P. Egerton, ibid. p. 135, woodc. figs. 5, 6. 

[Edinburgh Museum.] 
1875. Coccosteus decipiens, W. H. Baily, Figs. Charact. Brit. Foss. 

pl. xxxiii. fig. 3. 
1880. Brachydeirus milleri, A. von Koenen, Zeitschr. deutsch. geol. 

Ges. vol. xxxii. p. 675. 
1883. Brachydeirus milleri, A. von Koenen, Abh. phys. CI. k. Ges. 

Wiss. Gottingen, vol. xxx. p. 20. 
1883. Brachydeirus pusillus, A. von Koenen, ibid. p. 20. 

1888. Coccosteus decipiens, II. H. Traquair, Geol. Mag. [3] vol. v. 
p. 511. 

1889. Coccosteus decipiens, R. H. Traquair, ibid. vol. vi. p. 4, pl. i. fig. 2. 

Type. Imperfect skeletons ; British Museum. 

The type species, attaining a maximum length of about 0*4. 
Cranial shield hexagonal in form, the outer lateral angles acute, 
and the breadth between the latter considerably greater than the 
total length ; median occipital much broader than long, abruptly 
truncated in front, its anterior end being only half as broad as the 
posterior ; the anterior two- thirds of the shield gradually arched 
from side to side, flattened or depressed above, and the posterior 
portion of the median occipital plate rising to a sharply bent longi- 
tudinal ridge, corresponding to the laterally-arched contour of the 
median dorsal plate of the trunk immediately behind. Median 
dorsal plate as long as the cranial shield, and twice as long as 
broad, much arched from side to side, gradually tapering in its 
posterior half and produced into a long, blunt point ; anterior 
border slightly excavated. Anterior ventro-lateral plates not much 
longer than broad, shorter than the posterior ventrolaterals, which 
are twice as long as broad and produced at each postero-lateral 
angle into a short spine ; exposed portion of both median ventral 
plates longer than broad, the lateral angulation of the posterior 
median being almost at its middle point. Tuberculations of mode- 
rate size, never confluent, and rarely, except in the lateral plates, 



284 ARTHRODIRA. 

arranged in definite lines. Unarmoured caudal region somewhat 
longer than the head and armoured portion of the trunk ; dorsal 
fin with about fifteen double series of endoskeletal supports, arising 
at a distance equal to its own length behind the great dorsal plate. 
Form. <$f Loc. Lower Old lied Sandstone : Banffshire, Nairn- 
shire, Cromarty, Ross-shire, Caithness, and Orkney 1 . 

(i.) Orkney Isles (typical C. decipiens). 

P. 3214-5. Two of the type specimens figured by Agassiz, op. cit. 
pi. vii. and pi. ix. fig. 2. The relative elongation of the 
haemal arches in the abdominal region is conspicuous, and 
in the second specimen the double series of supporting 
bones of the dorsal fin is distinct. The latter fossil also 
exhibits remains of a longitudinal grooved streak (calcified 
lateral line) along the vacant space originally occupied by 
the notochord ; and appearances on the ventral aspect are 
suggestive of the radial cartilages of a pelvic fin attached 
to a small arched basipterygium. Ennislcillen Coll. 

P. 535, P. 535 a, P. 536 a. Two of the type specimens, the first in 
counterpart and figured, op. cit. pi. viii. pi. ix. fig. 1, the 
second figured, op. cit. pi. ix. fig. 3. The anterior dorso- 
lateral plates in the former exhibit the rounded articular 
r process on the inner margin. The apparently curved 
process of the posterior outer angle of the posterior 
ventro- lateral plate is an impression of the small curved 
pelvic basipterygium. Egerton Coll. 

P. 536. Posterior median ventral plate, figured by Agassiz, op. cit. 
pi. xxx. a. fig. 19. Egerton Coll. 

P. 3216, P. 3216 a. Two slabs from Eamna Gio, each with an im- 
perfect specimen and the crushed carapace of another. 
The second specimen displays the double series of about 
twelve supporting bones of the dorsal fin and a fragment 
evidently of the fin-membrane itself; also one of the 
pelvic basipterygia and a fragment of indeterminable 
fossilized tissue in the anal region. Enniskillen Coll. 

P. 550. Portion of trunk, showing dorsal fin-supports, the elon- 
gation of the abdominal haemal arches, and an indeter- 
minable patch of tissue in the anal region. Egerton Coll. 

1 This species is also considered to occur in the Russian Devonian by E. Ton 
Eichwald, Leth. Rossica, vol. i. (1860), p. 1522. 



COCCOSTEIDJE. 285 

P. 687-8. Two specimens, one showing the impressions of several 
plates and nearly all the axial skeleton of the trunk and 
tail, the other considerably resembling No. P. 536 a, 
though with only half of the caudal region. The first 
specimen was obtained from Bamna Gio, the second from 
Belyacreugh. Egerton Coll. 

P. 180. A well-preserved skeleton showing portions of the double 
series of supporting bones and membrane of the dorsal 
fin, one of the pelvic elements, and a quadrate patch of 
tissue in the anal region. The median dorsal plate, the 
left dorso-laterals, laterals, and ventrolaterals are espe- 
cially well displayed. Purchased, 1881 . 

P. 181. Small more imperfect individual, similarly crushed. 

Purchased, 1881. 

43966. Crushed individual, imperfectly preserved, displaying the 
supporting bones of the dorsal fin. The armoured portion 
measures about 0*17 in length, and the unarmoured caudal 
region 0*205. Purchased, 1872. 

P. 5964-65. Two crushed specimens, the first showing possible 
traces of a pelvic fin, the second with the pelvic basi- 
pterygium. Purchased, 1889. 

20645* Nearly complete individual, imperfectly preserved • Strom- 
ness. Purchased, 1846. 

P. 4310. Six portions of dermal armour, detached from matrix. 

Ennishillen Coll. 

P. 691. Imperfect detached mandibular ramus, partly in impression ; 
Belyacreugh. This and the following specimen are 
probably referred to by Newberry (Palaeoz. Fishes N. 
America, 1889, p. 132) as closely resembling the man- 
dibular rami of Dinichthys. The beak-like appearance, 
however, is due entirely to the accidental flaking of the 
bituminous substance into which the fossils are converted. 

Egerton Coll. 

P. 3217. Similar jaw. Ennishillen Coll. 

P. 4310 a. Detached mandibular ramus, showing teeth and two of 
the anterior denticulations. Ennishillen Coll. 

P. 692. Median ventral plate of small individual. Egerton Coll, 



128(5 ARTHRODIRA. 

(ii.) Caithness. 

49663. Imperfect remains of a very large individual, displaying the 
same aspect as the two last-mentioned specimens ; Hol- 
burn Head. Purchased, 1879. 

20346. Median dorsal plate and imperfectly preserved caudal region. 

Purchased, 184(5. 

(iii.) Edderton, near Tain, Ross-shire. 

38727. Imperfect head, dorsal aspect, and several portions of plates 

of the trunk. Purchased, 1865. 

39896. Inferior aspect of imperfect cranial roof. Purchased, 1866. 

P. 695, P. 1171. Roof of skull, imperfect laterally ; also the im- 
pression of a similar specimen associated with a mandibular 
ramus and portions of the plates of the trunk. 

Ecjerton Coll. 

P. 5600. Less imperfect example, with displaced maxillaries and 
premaxillaries, one of the latter apparently exhibiting the 
notch interpreted as nasal by Traquair. The specimen 
also exhibits one of the anterior dorso-lateral plates. 

Harford Coll. 

38728. Crushed median dorsal plate, associated with portions of 

other plates, fragments of the axial skeleton, and a small 
undetermined, almost reniform element, apparently un- 
ornamented. Purchased, 1865. 

41729. Imperfect median dorsal plate, probably uncrushed, asso- 
ciated with portions of other plates. In the median 
dorsal the rounded longitudinal keel only extends along 
the posterior two-thirds of the bone, the surface sloping 
downwards both in front and on each side of its com- 
mencement. Purchased, 1869. 

?. 695 a, P. 1171 a. Portions of the dorsal and ventral plates of the 
trunk, with the supporting bones of the dorsal fin and 
part of the axial skeleton, in counterpart. Remains of 
the pelvic elements are distinguishable, and in the ab- 
dominal region the small unornamented plate, figured 
below in Xo. 43617, is exhibited. Egertort Coll. 

P. 1171 b, P. 3220 a. Ventral plates of trunk, with remains of 
dorsal and lateral plates, in counterpart. 

Egfrton 4' Eunkkillen Colls. 



coccosteidj:. 287 

P. 6074. Several associated imperfect plates of the trunk. 

Presented by F. Harford, Esq., 1889. 

(iv.) Cromarty (C. decipiens). 

41728. Cranial shield, upper aspect, considerably broken. 

Purchased, 1869. 

P. 3220. Similar specimen. Ennislcillen Coll. 

P. 696. Plaster cast of mandibular rami, showing anterior denticu- 
lations, the original specimen in the Edinburgh Museum, 
and probably the basis of Miller's description (Old Red 
Sandst. p. 57). Egerton Coll. 

19057-58, 19069. Three specimens showing various plates, chiefly 
of the trunk, the third also exhibiting portions of man- 
dible and teeth. Purchased, 1845. 

20649, 20651-52. Remains of median dorsal plate showing inner 
longitudinal ridge, bifurcated inferiorly ; also a similar 
crushed plate, in counterpart. Purchased, 1846. 

30872-73. Median dorsal and posterior ventro-lateral plates, the 
second preserved in counterpart. Purchased, 1856. 

P. 5062. Median dorsal plate. Presented by J. E. Lee, Esq., 1885. 

(v.) Lethen Bar (typical C. oblongus). 

P. 3222-23. Type specimens of Coccosteus oblongus, figured by 
Agassiz, op. cit. pi. xi. Ennislcillen Coll, 

P. 685 a, P. 3224 a. Dermal armour of head and trunk, imper- 
fectly preserved, in counterpart. Teeth are observed 
in the mandible, relatively more slender than those of 
No. P. 3222. Egerton 6f Ennislcillen Colls. 

P. 3224. Three examples of the head and portions of the dermal 
armour of the trunk. Two specimens seem to indicate the 
presence of a deep pit on the inferior aspect of the so-called 
posterior ethmoid plate (described above as pineal). 

Ennislcillen Coll. 

P. 685 "b, P. 2078. Two examples of the head and armoured portion 
of the trunk, with fragments of the axial skeleton, the 
second also showing the small thin plate in the abdominal 
region already noted in Nos. P. 3216, P. 550, P. 180, 
38728, and P. 695 a. Egerton Coll. 



2SS ARTHRODIRA. 

P. 685. Ten specimens exhibiting plates of the head and trunk. 

Egerton Coll. 

49185-86. Two specimens of the head and armoured trunk, in 
counterpart. Broad teeth are shown in the mandible of 
both specimens. Purchased, 1876. 

21574, a, b. Three examples of the dermal plates of the head and 
trunk, the second and third being preserved in counter- 
part. In the first specimen the median occipital of the 
cranial shield exhibits the characteristic median elevation, 
and the "posterior ethmoidal" (pineal) shows a distinct 
cast of the large central pit on its inferior aspect. 

Presented by Norman McLeod, Esq., 1847. 

20792 a-b. Fine example of the dermal plates of the head and 
trunk, preserved in counterpart. The maxillary or sub- 
orbital elements are displaced, and the supposed operculum 
is observed immediately behind on each side. The tuber- 
cular ornament is very coarse ; and behind the median 
dorsal plate there occurs one of the pelvic basipterygia. 

Presented by Col. Sir Proby T. Cautley, K.C.B., 
and — Gordon, Esq., 1847. 

P> 5960-1. Two specimens showing various dermal plates, the first 
including the mandibular rami with teeth. 

Purchased, 1889. 

P. 685 C Median dorsal plate, broken to exhibit the extent of the 
inner longitudinal keel. Egerton Coll. 

P. 5060. Median dorsal plate. Presented by J. E. Lee, Esq., 1885. 

P. 6073. Median dorsal plate with imperfect portions of other 
elements. Presented by F. Harford, Esq., 1889. 

P. 3225. Crushed median dorsal plate. Enniskillen Coll. 

(vi.) Tynet Burn. 

43617. Imperfect individual wanting the posterior half of the 
caudal region, lateral aspect, in counterpart. The dermal 
plates of the head and trunk are much broken, but several 
characteristic elements are exhibited ; while the region 
immediately behind the armour is especially well preserved. 
The latter is shown, of the natural size, in PI. VII. fig. 2, 
and the parts are lettered in accordance with the following 
description. Emerging from beneath the median dorsal 



C0CC03TEIDJB. 289 

plate (d.) is tho closely arranged series of robust neural 
arches with their spiues (?i.), bounding above the narrow 
vacant space (not.) originally occupied by the persistent 
notochord ; and some of these arches exhibit indications 
of a zygapophysial union. Below the notochordal space 
there is a corresponding series of haemal arches and spines 
(h.), gradually becoming much lengthened towards the 
end of the abdominal region and shortening again in the 
caudal. A short distance behind the dorsal shield the 
neural spines also become lengthened for the support of 
the double series of about 13 basal cartilages (6 l , 6 2 ) of 
the dorsal fin, which are as robust as the neural spines 
themselves and are directly apposed to the ends of an 
equal number of the latter. The membrane of the dorsal 
fin is not observed, but remains of a small Diplacanthug 
occur in the position it would originally occupy. Behind 
and above the posterior ventro-lateral plates (p.v.l.) are 
preserved the right and left pelvic basipterygia (£>?*>.), 
attenuated above, but widened to a club-shaped extremity 
below, with one or two deep pits or foramina (/.) pene- 
trating this expansion. Apposed to the broad end of one 
of these cartilages is a series of four or five short stout 
rays (r.), while directly behind the same cartilage are 
indications apparently of longer rays of a similar character 
(see also No. P. 3215) ; these, like all the other endo- 
ekeletal elements, being only calcified in a thin layer at 
the surface. Portions of a longitudinal white streak (I. I.) 
along the vacant space between the neural and haemal 
arches are suggestive of dermal calcifications along the 
lateral line (see also No. P. 3215) ; and the problematical 
azygous plate (x.) at the commencement of the caudal 
region, already noted in several specimens, is especially 
conspicuous. This plate is quadrate in form, with a 
convex inferior border, is evidently very thin, and exhibits 
prominent concentric lines of growth. Purchased, 1872. 

44586. Cranial shield, with displaced maxillo-suborbitals, in coun- 
terpart, shown of the natural size in PI. VII. fig. 1. The 
specimen is apparently un crushed, thus exhibiting the 
original contour ; most of the sutures and some of the 
sensory canals are distinct, and are seen to be disposed as 
in Dr. Traquair's restoration (fig. 42, p. 279) ; and the 
superficial tuberculations are unusually coarse. 

Purchased, 1873. 

PART II. V 



290 ARTHRODIRA. 

35776, P. 6266. Median dorsal plate, in counterpart. 

Purchased, 1869, and Enniskillen Coll. 

43277. Imperfect median dorsal plate, showing keel. 

Purchased, 1871. 

(vii.) Gamrie (typical C. cuspidatus). 

28861-a. Two examples of the cranial shield, dorsal aspect, con- 
siderably fractured. Purchased, 1854. 

39177. Crushed remains of dermal plates of head and trunk. 

Bowerbank Coll. 

47867. Much crushed and broken dermal plates of head and trunk, 
with a few of the neural and hsemal arches and dorsal 
fin-supports, lateral aspect, preserved in counterpart. 
Some of the teeth are of the broad, blunt type described 
as characteristic of C. oblongus; and the hinder outer 
angles of the posterior ventro-lateral plates are produced 
into unusually long spines. Purchased, 1877. 

P. 694, P. 3218-9. Specimen exhibiting several plates, including 

the inner aspect of an anterior dorso-lateral ; also three 

l imperfect cranial shields, with other plates, in counterpart. 

Egerton Sf Enniskillen Colls. 

P. 4926. Eemains of various plates of the head and trunk, partly 
in counterpart. Presented by Prof. J. Prestwich, 1885. 

39178. Fractured dermal bones. Bowerbank Coll. 

28861 b. Hinder extremity of armour of trunk, with remains of the 
neural and haemal arches of the axial skeleton. 

Purchased, 1854. 

The following specimens are noticed in the letters by Hugh 
Miller, quoted in Quart. Journ. Geol. Soc. vol. xvi. (1860), pp. 128- 
136:— 

Po 5143. Series of eight plaster casts, figured loc. cit., woodcuts 1-6, 
8, 9. Egerton Coll. 

P. 5144. Paper model of tail of Coccosteus, as interpreted by Miller, 
figured ibid. p. 134, woodcut 7. Egerton Coll. 



C0CC0STE1DJ":. 



291 



Coccosteus minor, Miller. 

1858. Coccosteus minor, H. Miller, l Cruise of the Betsey,' etc. p. 396. 

1888. Coccosteus minor, R. II. Traquair, Geol. Mag. [3] vol. v. p. 511. 

1889. Coccosteus minor, R. H. Traquair, ibid. vol. vi. p. 8, pi. i. fig. 3. 

Type. Imperfect skeletons ; Edinburgh Museum. 

A very small species, attaining a maximum total length of about 
0-1. Cranial shield broader than long; mandibular teeth very 
slender and sharply pointed ; infra-orbital bar of maxillo-suborbital 
bone relatively deep. Median dorsal plate about twice as long 
as broad, somewhat arched from side to side, gradually tapering 
in its posterior half into a long, blunt point ; anterior border slightly 
excavated, and the granulations much finer along the mesial longi- 
tudinal line of the shield than at its sides. Posterior ventro-lateral 
plates twice as long as broad, produced ab each postero-lateral angle 
into a short spine. Tuberculations numerous, of moderate size, never 
confluent, and not arranged in definite lines. Unarmoured caudal 
region about equal in length to the head and armoured portion of 
the trunk. 

As remarked by Hugh Miller, the remains of individuals of this 
species occur in groups, at first sight suggestive of their being shoals 
of young. 

Form. § Loc. Lower Old Red Sandstone : Caithness and Orkney. 

42383. Three imperfect associated individuals ; Murkle Bay, Caith- 

ness. Peach Coll. 

42335. Remains of two or more individuals on one slab, showing 
stout well-ossified neural and haemal arches of axial 
skeleton ; Murkle Bay. Peach Coll. 

42384, 42387-89. Four small slabs with scattered dermal plates ; 

Murkle Bay. The second specimen exhibits a mandi- 
bular bone with teeth. Peach Coll. 

42386. Imperfect median dorsal plate, ventral aspect ; Thurso. 

Peach Coll. 

P. 689. Slab with scattered dermal plates of several individuals, 
probably of this species ; Orkney. Egerton Coll. 

P. 3221-a. Two slabs with scattered dermal plates ; Orkney. The 
second specimen shows an imperfect median dorsal plate 
exhibiting some of the characters stated in the diagnosis. 

Ennishillen ColL 

v2 



29li ARTURODIEA. 

Coccosteus disjectus, sp. nov. 
[Plate VIII. figs. 1-4.] 

Type. Associated median ventral plates ; British Museum. 

An imperfectly known species of moderate size. Anterior median 
ventral plate much broader than long, its obtuse posterior angle 
completely exposed and overlapping the anterior border of the 
median ventral ; median ventral nearly twice as long as broad, its 
anterior extremity truncated, and its lateral angulation situated 
much behind the middle point. Posterior ventro-lateral plates 
nearly two-thirds as broad as long. Tuberculations of moderate 
size, having a somewhat radiating arrangement upon the anterior 
median ventral plate. 

Form, fy Loc. Upper Old Red Sandstone : Kiltorcan, Kilkenny, 
Ireland. 

43039. Type specimen exhibiting the form and proportions of the 
associated median ventral plates, shown, of the natural 
size, in PI. VIII. figs. 1,2. In fig. 2 the anterior ex- 
tremity has been inadvertently directed downwards. 

Purchased, 1871. 

P. 3226-a. Two similar plates more imperfectly preserved. 

Enniskillen Coll. 

41901. Right posterior ventro-lateral plate, inner aspect, shown, of 
the natural size, in PI. VIII. fig. 3. Purchased, 1870. 

43039 a. Fragment of plate, with ornamentation, partly shown, 
of twice the natural size, in PI. VIII. fig. 4. 

Purchased, 1871. 

Coccosteus hercynius, H. von Meyer. 

1852. Coccosteus hercynius, H. von Meyer, Palaeontogr., vol. iii. p. 82, 
pi. xii. fig. 28. 

Type. Associated dermal plates. 

An imperfectly known species, nearly equal to the typical C. de- 
cipiens in size. Median occipital scarcely broader than long. 
Median dorsal plate less than twice as long as broad, the anterior 
border excavated, and the posterior border rounded. Posterior 
ventro-lateral plates more than three times as long as broad, much 
longer than the median dorsal. Tuberculations large, numerous, 
never confluent. 

Form. § Loc. Lower Devonian : Harz Mts. 



C0CC0STEID.E. 293 

P. 6267. Two imperfect ventro -lateral plates, doubtfully of this 
species ; Goslauer Schiefer, Kutthal. Purchased. 

The following portions of median dorsal plates of Coccosteus ex- 
hibit the internal longitudinal ridge as strongly developed as in a 
specimen from Livonia figured by Pander l , and are ascribed by 
Trautschold to a species supposed to possess pectoral appendages, 
under the name of Coccosteus wegalopteryx, Trautschold 2 . If the 
pectoral appendages are correctly associated with the plates, the 
species does not pertain to Coccosteus ; if not, the specific name is 
too inapplicable for adoption. 

P. 4731. Two fragments of the posterior portion of the median 
dorsal element, and one specimen showing the greater 
portion of the internal longitudinal ridge ; Devonian, River 
Ssjass, Govt, of St. Petersburg. Purchased, 1884. 

The following specimen is specifically undetermined : — 

P. 5282. Imperfect median dorsal plate described and figured in. 
Geol. Mag. [2] vol. vii. (1880), p. 146, pi. v. fig. 3 ; 
Upper Devonian, near Chudleigh, S. Devon. 

Presented by John Edward Lee, Esq., 1835. 

The following species have also been described, but are not re- 
presented in the Collection : — 

Coccosteus obtusus, H. Trautschold, Zeitschr. deutsch. geol. Ges. 
vol. xli. (1889), p. 44, pi. v. figs. 7-9, pi. vi. figs. 1, 2 (?in 
part). — Devonian ; Ssjass, Russia. [Imperfect detached 
plates ; Trautschold Coll., Breslau.] 

Coccosteus occidentalis, J. S. Newberry, Rep. Geol. Surv. Ohio, 
vol. ii. pt. ii. (1875), p. 32, pi. liv. fig. 2. — Corniferous 
Limestone (Lower Devonian) ; Delaware, Ohio. [Dorsal 
plate ; Columbia College, New York.] 

As remarked by Newberry (Palaeoz. Fishes N. America, p. 52), 
it seems not unlikely that to the latter species must be referred the 
mandibular ramus named Liognathus spatulatus, J. S. Newberry, 
Rep. Geol. Surv. Ohio, vol. i. pt. ii. (1873), p. 306, pi. xxix. fig. 4. 
This is also preserved in the Museum of Columbia College. 

1 C. H. Pander, Placoderm. devon. Syst. (1857), pi. B. fig. 4. 

2 H. Trautschold, Verhandl. russ.-kais. mineral. Gesell. [2] vol. xv. (1880), 
p. 145, pis. vi., ix., x.; also Zeitschr. deutsch. geol. Gresell. vol. xli. (18S9), 
p. 35, pis. iii., iv., pi. v. figs. 1-6. 



'204: ARTHI10D1RA. 

Dermal plates of Placoderins, too imperfect for satisfactory deter- 
mination, have also been assigned to Coccosteus under the following 
names : — 

Coccosteus agassizi, J. Barrande, Syst. Silur. Boheme, vol. i. suppl. 
(1872), p. 638, pi. xxix. figs. 3, 4, 6-8.— Upper Silurian 
(gl); Chotecz, Bohemia. [Royal Bohemian Museum.] 

Coccosteus fritschi, J. Barrande, ibid. (1872), p. 639, pi. xxx. 
figs. 1-6. — Upper Silurian (g 1); Schwagerka quarry, 
Hlubo^ep, Bohemia. [? Aspidichihys.~\ [Royal Bohemian 
Museum.] 

Coccosteus obtusus, C. H. Pander, in A. von Keyserling, Reise in 
das Petschoraland (1846), p. 292 6. — Devonian ; River 
Uchta, Petchora Land. 

Coccosteus obtusus, A. von Koenen (non Pander), Abh. phys. CI. 
k. Gesell. Wiss. Gottingen, vol. xxx. (1883), p. 10 ; Yer- 
handl. natur. Yerein. preuss. Rheinl. etc. vol. xliii. (1886), 
p. 55, woodc. 1, 2 : Brachydeirus obtusus, A. von Koenen, 
torn. cit. (1883), p. 21. — Upper Devonian; Wildungen, 
Bicken, and Miillenborn, Eifel. [? Holonema.~] 

Coccosteus primus, J. Barrande, torn. cit. (1872), p. 640, pi. xxix. 
figs. 1, 2. — Upper Silurian (f 2) ; Konieprus, Bohemia. 
[Royal Bohemian Museum.] 

Genus BRACHYDIRUS, A. von Koenen. 
[Zeitschr. deutsch. geol. Ges. vol. xxxii. 1880, p. 675, and Abh. 
phys. CI. k. Ges. Wiss. Gottingen, vol. xxx. 1883, p. 20 (as 
subgenus of Coccosteus).'] 

Shield of head and abdominal region closely resembling that of 
Coccosteus, but more laterally compressed. Pectoral limbs represented 
by a slender, hollow spine. {A. von Koenen.) 

Some doubtful diagnostic characters are also noticed by von 
Koenen in the suture between the cranial and abdominal shields. 
As remarked by Traquair l , the presence of a pectoral spine suffices 
to distinguish this form generically from Coccosteus, in the typical 
species of which no such appendage exists. 

The following species are recognized : — 

Brachydirus biclcensis : Coccosteus bickensis, A. von Koenen, 
Zeitschr. deutsch. geol. Ges. vol. xxviii. (1876), p. 667, 
and ibid. vol. xxxii. (1880), p. 673, and Abh. phys. CI. k. 

1 Geol. Mag. [3] vol. vii. (1890), p. 235. 



COCCOSTEID.E. 



295 



Ges. Wiss. Gottingen, vol. xxx. (1883), p. 17, pi. i. fig. 3, 

pi. ii. fig. 2, pi. iv. figs. 5, 7. — Upper Devonian ; Bieken, 

Eifel. 
Brachydirus bidorsatus, A. von Koenen, Abh. phys. CI. k. Gesell. 

Wiss. Gottingen, vol. xxx. (1883), p. 28, pi. i. figs. 2, 4: 

Coccosteus bidorsatus, A. von Koenen, Zeitschr. deutsch. 

geol. Gesell. vol. xxxii. (1880), p. 674. — Upper Devonian ; 

Bieken. 
Brachydirus carinatus, A. von Koenen, ibid. (1883), p. 31, pi. ii. 

fig. 1 : Coccosteus carinatus, A. von Koenen, torn. cit. 

(1880), p. 673. — Upper Devonian ; Bieken. 
Brachydirus inflatus, A. von Koenen, torn. cit. (1880), p. 674, 

and torn. cit. (1883), p. 26, pi. i. fig. 1, pi. iv. figs. 1, 2, 

3, 6. — Upper Devonian ; Bieken. 
The type specimens are preserved in the Royal Geological 
Museum, Gottingen. 

Genus PHLYCTVffiNASPIS, Traquair. 
[Geol. Mag. [3] vol. vii. 1890, pp. 60 {Phlyctcenius l ), 144.] ' 

Head and trunk broad, the dorsal aspect more or less arched from 
side to side ; scutes ornamented with stellate tubercules, and those 
of the upper surface of the head also marked with deep sensory 
furrows. Elements of cranial shield, except the rostral bone, fused 
together in the adult, and the occipital bones constituting not more 
than half of its total length ; median occipital elongated antero- 
posteriorly, and its anterior end produced between the divergent 
hinder extremities of the pair of central plates ; no median element 
over the pineal region, and no foramen ; orbits forming broad notches, 
not bounded externally. [Arrangement of plates upon trunk un- 
known, but probably as in Coccosteus.'] 

So far as known, the species of this genus do not exceed those of 
Coccosteus in size. 

Phlyctsenaspis acadica (Whiteaves). 

1881. Coccosteus acadicus, J. F. "Whiteaves, Canadian Nat. n. s. vol. x. 
p. 94, woodc. 

1889. Coccosteus acadicus, J. F. Whiteaves, Trans. Roy. Soc. Canada, 
vol. vi. sect. iv. p. 93, woodc. fig. 2, pi. ix. 

1890. Phlyctcenaspis acadicus, R. H. Traquair, Geol. Mag. [3] vol. vii. 
pp. 20, 60, pi. iii. figs. 1, 2. 

Type. Cranial shield and detached plates ; Geol. Survey of Canada, 
Ottawa. 

1 Non Phlyctcenium, Zittel, Xeues Jahrb. 1878, p. 62. 



296 ARTHRODIRA. 

The type species. Cranial shield ovoid in form, truncated at its 
hinder border, the outer lateral angles rounded and notched, and 
the breadth between the latter about equal to the total length ; the 
anterior two-thirds of the shield gradually arched from side to side, 
flattened or depressed mesially, the posterior portion of the median 
occipital plate rising to a broad, low, longitudinal ridge, corresponding 
to the laterally arched contour of the median dorsal plate of the 
trunk immediately behind. Median dorsal plate about three times 
as long as broad, convex in the median line, but highest in the 
centre, from which point there is a downward slope in every direc- 
tion, the lateral slopes being most abrupt ; anterior border not ex- 
cavated ; the sides parallel for more than two-thirds of their length, 
then converging rapidly into a point with somewhat concave sides. 
Tuberculations of small or moderate size, often arranged in close, 
concentric series, especially upon the laterally situated plates. 
Form. § Loc. Lower Devonian : Campbellton, New Brunswick. 

P. 5474-75, P. 5972. Three imperfect cranial shields, the first 
about 0*1 in maximum breadth, the second and third dis- 
playing the linear arrangement of the tubercles. 

Purchased, 1888, 1889. 

P. 5973. Imperfect plate of the form named " ventro-median (?) " 
by *VVhiteave8, but appearing to the present writer to be 
the anterior lateral element. Purchased , 1889. 

Phlyctsenaspis anglica, Traquair. 
[Plate VIII. figs. 5-8.] 

1870. Zenaspis (Cephalaspis) salweyi, E. R. Lankester (errore), Fishes 
Old Red Sandst. pt. i. (Pal. Soc), p. 55, pi. viii. fig. 4 (? figs. 2, 3), 
pi. xiii. figs, 17, 18. 

1890. Phlyctrenius anglicus, R. H. Traquair, Geol. Mag. [3] vol. vii. 
p. 85, pi. iii. fig3. 3, 4. 

Type. Imperfect cranial shield ; Edinburgh Museum. 

Cranial shield ovoid in form, truncated at its hinder border, the 
outer lateral angles rounded, but not notched, and the breadth be- 
tween the latter about equal to the total length. Tuberculations 
of cranial plates relatively very large, but irregular both in size and 
arrangement, rarely in concentric series ; those of the supposed 
ventral body-plates exhibiting a more or less definite concentric 
serial arrangement, and some of the rows very minute. 

Some fragments of this species were assigned by Lankester to un- 
determined positions in the dermal armature of Cephalaspis salweyi; 



COCCOSTEID.E. 



297 



and a bilaterally symmetrical ridge-scute, having a similar ornament, 
was regarded as occupying an anterior position on the dorsal aspect 
of the trunk of the same fish. The latter fossil may be the dorsal 
plate of Phlgctcenasjpis anglica, but its determination still remains 
uncertain. 

Form. 4' Loc. Lower Old Red Sandstone (Cornstones) : Hereford- 
shire. 

42147- Cranial shield, imperfect postero-laterally, chiefly shown as 
an impression of the outer aspect upon the matrix ; 
Cradley. The specimen is noticed by Traquair, loc. cit. 
p. 59, pi. iii. fig. 4, and is also shown, of the natural size, 
in PI. VIII. fig. 5. The excavation for the median rostral 
plate is distinct anteriorly, and there are faint traces of 
the sutures between the preorbital (p.o.), central (c), and 
median occipital (m.o.) plates. The outlines of some of 
the lateral plates may also possibly be distinguishable ; 
and the principal lateral grooves for the sensory canals 
are very prominent. The coarse, irrregular nature of the 
ornamentation is well displayed, and most of the tubercles 
are broken in the depressions they leave in the matrix. 

Baugh Coll. 

37388. Greater portion of cranial shield, exhibited partly from the 
inner aspect, partly in impression of the external tuber- 
culated surface, and shown, of the natural size, in PI. VIII. 
fig. 6 ; Heightington, Worcestershire. The small, trans- 
versely elongated rostral plate (r) is retained in position 
and exhibits a somewhat finer and closer granulation than 
the other elements ; it is almost oval in form, with pointed 
lateral extremities. The closed sutures between the pre- 
orbital (p.o.), central (<?.), and median occipital (m.o.) bones 
are also distinct ; and the lateral grooves of the sensory 
canal-system exhibit their usual prominence. 

Purchased, 1863. 

37388 a. Fragmentary cranial shield, with some of the faintly 
stellate tubercles disengaged from matrix ; Heightington. 

Purchased, 1863. 

38032. Imperfect cranial shield, wanting rostral plate, shown 
chiefly as an impression of the external aspect ; Height- 
ington. Purchased, 1864. 

42148. Fragmentary impression of larger specimen ; Hereford- 
shire. Baugh Coll, 



293 



ARTHRODIRA. 



38032 a. Portion of shield ; Heigbtington. Purchased, 1864. 

38032 b. Fragment with impression of tubercular ornament, 
exhibiting a tendency towards a concentric arrangement, 
and partly shown, of the natural size, in PI. VIII. fig. 7 ; 
Heightington. Purchased, 1864. 

37388 b. Imperfect flat plate, shown, of the natural size, in PI. VIII. 
fig. 8, and probably referable to the ventral armature of 
the trunk. Two of the four borders of the plate are 
apparently thicker than the others, are unbroken, and 
meet in a wide, rounded angle ; the tubercles are arranged 
in series concentric with these borders for some distance 
towards the centre of the plate, and gradually decrease in 
size until they become very small inwards. 

37388 C, 38032 c. Two nearly similar plates ; Heightington. 

Purchased, 1864. 

The following is a bilaterally-symmetrical ridge-plate, resembling 
that assigned to Zenaspis by Lankester, ojj. cit. pi. viii. figs. 2, 3 ; 
reasoning from the shape of the plate and the character of its orna- 
mentation, it may well be the dorsal shield of the trunk of Phlyc- 
tcenasj>is anglica. 

38032 d. Internal cast of shield, with fragments of the bony tissue 
and its characteristic .ornamentation preserved at what 
appears to be the hinder extremity ; Heigh tiogton. There 
are remains of an inner longitudinal keel, apparently re- 
sembling that of the median dorsal plate in Coccosteus. 

Purchased, 1864. 

The following specimens from the Lower Old Red Sandstone of 
Herefordshire may also pertain to Coccosteidae related to Phlyctcen- 
asjpiS) but their determination is quite uncertain : — 

P. 194. An oval plate, exposed from the inner aspect, truncated 
at one extremity, measuring 0*095 in length and 0*063 
in maximum breadth. There is a longitudinal median 
elevation in one half of the shield, and an impression 
of part of the outer aspect shows that it was coarsely 
tuberculated. Weaver-Jones Coll. 

P. 5274. Two small ridge-scutes, probably of an imbricating series, 
and externally ornamented with large tubercles ; Cradley. 
One specimen is shown, of the natural size, in PL VIII. 
fig. 9. Purchased, 1885. 



C0CC0STEID.B, 299 

Fragments of the shield of an undetermined species of Pldyclam- 
aspis, with an ornamentation much resembling that of P. anglica, 
have also been discovered in the Lower Devonian of Kussian Poland 
(Coccosteus, A. von Alth, Abhandl. k. k. geol. Eeichsanst. vol. vii. 
pt. i. 1874, p. 38, pi. iii. figs. 16-21). 



Genus CHELYOPHORUS, Agassiz. 

[Poiss. Foss. V. G. R. 1845, p. 135.] 

Dorsal shield arched from side to side ; scutes ornamented with 
granulations, more or less elongated, confluent, and often arranged 
in sinuous or vermiculating lines ; neural and haemal arches well 
calcified, and the caudal region destitute of armour. Elements of 
cranial shield not fused in the adult, and the occipital bones consti- 
tuting less than half of its length ; orbits forming broad notches, 
not bounded externally ; a median pineal foramen ; parachordal 
cartilage ossified ; [jaws unknown]. Dermal armour of trunk pro- 
bably as in Coccosteus. 

This genus comprises species of small or moderate size, and does 
not appear to be represented in the Collection. The finest specimen 
hitherto described is the imperfect head and trunk of C. primigenius 
in the University of St. Petersburg ; this showing one of the support- 
ing cartilages of the dorsal fin, interpreted by Eichwald as a dorsal 
fin-spine. There is no certain evidence of paired appendages. 
Several detached plates have been described and figured by Pander 
(Placoderm. devon. Syst. p. 86, pi. vii. figs. 3, 9-15, 31), and com- 
pared with the corresponding plates of other genera ; and the follow- 
ing species are recognized : — 

Chelyophorus primigenius, E. von Eichwald, Leth. Rossiea, vol. i. 
(1860), p. 1525, pi. lvii. figs. 1-3.— Devonian ; Govt, of 
Orel. [Imperfect skeleton ; University of St. Peters- 
burg.] 

Chelyophorus verneuili, L. Agassiz, Poiss. Foss. Y. G. R. (1845), 
p. 135, pi. xxxi. a. figs. 14-19 j G. Fischer de Waldheim, 
Bull. Soc. Imp. Nat. Moscou, vol. xxv. (1852), pt. i. p. 172, 
pi. ii. figs. 1-5 ; E. von Eichwald, Leth. Rossica, vol. i. 
(1860), p. 1529 ; C. H. Pander, Placoderm. devon. Syst. 
(1857), p. 96 ; H. Trautschold, Zeitschr. deutsch. geol. 
Ges. vol. xli. (1889), p. 46, pi. vi. figs. 3-6. — Devonian ; 
Govt, of Orel and Livonia. [The type species, founded on 
detached plates.] 



300 arthrodira. 

I>y E. von Eichwald (torn. cit. p. 1529, pi. lvii. figs. 4, 5), the 
originals of Pander's pi. vii. figs. 3, 9, 15, are assigned to C. ver- 
neuili ; while those of the latter author's pi. vii. figs. 3 6, &', 11, 12, 
14, with an indeterminable fragment named " plaque dentaire," are 
regarded as the types of a distinct species, C.posthumus. The so- 
called C. grifflthii, M'Coy (Ann. Mag. 2s 1 at. Hist. [2] vol. ii. 1848, 
p. 8), from the Lower Carboniferous of Cultra, Co. Down, Ireland, 
is a generically indeterminable jaw (C. H. Pander, op. cit. p. 87). 
[Dublin Museum.] 

Genus DINICHTHYS, dewberry. 

[Eep. Geol. Surv. Ohio, vol. i. pt. ii. 1873, p. 313.] 

Head and trunk broad, the dorsal aspect slightly arched from side 
to side ; scutes smooth or feebly marked with vermiculating rugae ; 
caudal region destitute of armour. Elements of cranial shield almost 
or completely fused in the adult, and the occipital bones constituting 
less than half of its total length ; a distinct small median hone over 
the pineal region, with a minute perforation ; orbits forming broad 
notches, not bounded externally : eye with a ring of few sclerotic 
plates ; maxilla distinct, and two inner pairs of dentigerous bones in 
the upper jaw ; mandibular rami suturally united at the symphysis, 
each beak-shaped in front, and bearing a short, single series of 



A. 




Diagrams of dentition of Dinichthys, after Newberry. — A, anterior, and B, 
lateral aspect of jaws of D. terrelli ; C, anterior aspect of jaws of 
D. hertzeri. 

acute teeth anchylosed just in advance of the middle of its oral 
margin. A single median dorsal shield upon the trunk, with an 
inner longitudinal keel, and rounded or acutely pointed posteriorly ; 
ventral armour of trunk well developed, consisting of two large 
lateral plates and a long narrow median element equivalent to the 
two diamond-shaped median bones of Coccosteus fused together ; 
ventral and dorsal armour united by lateral plates, of which the 
anterior dorso-lateral exhibits a large articulating eminence, but has 



COCCOSTFID^. 301 

no forwardly directed process. Pectoral arch represented by at least 
one pair of short and deep, curved bones, immediately in advance of 
the dorsal and lateral armour ; pectoral appendages with a short, 
robust spine. [Median fins unknown.] 

This genus comprises species chiefly of gigantic size, hut none are 
represented in the Collection. The following have been described : — 

Dinichthys corrugatus, J. S. Newberry, Palaooz. Fishes N. America 
(Hon. U.S. Geol. Surv. no. xvi. 1889), p. 151, pi. vii. fig. 3. 
— Cleveland Shale (Lower Carboniferous) ; Lorain Co., 
Ohio. [Anterior portion of mandible j Columbia College, 
New York.] 

Dinichthys curtus, J. S. Newberry, Trans. New York Acad. Sci. 
vol. vii. (1888), p. 179, and op. cit. (1889), p. 156, pi. 
xlviii. fig. 3, pi. liii. figs. 1-3. — Erie and Cleveland 
Shales ; Ohio and Pennsylvania. [Head, &c. ; Columbia 
College.] 

Dinichthys ? eifelensis, E. Kayser, Zeitschr. deutsch. geol. Ges. vol. 
xxxii. (1880), p. 818. — Devonian (" Crinoidenschicht ") ; 
Gerolstein, Eifel. [Mandibular ramus and fragmentary 
plates ; Geol. Surv. Museum, Berlin.] 

Dinichthys intermedins, J. S. Newberry, op. cit. (1889) p. 152, pi. x. 
figs. 1, 2, pi. xlvii. figs. 1-4, pis. li., lii. — Cleveland Shale ; 
Cuyahoga and Lorain Cos., Ohio. [Head, &c. ; Columbia 
College.] 

Dinichthys gouldi, J. S. Newberry, op. cit. p. 150, pi. ix. — Cleve- 
land Shale ; Rocky River, nearBerea, Ohio. [Head, &c. ; 
Columbia College.] 

Dinichthys hertzeri, J. S. Newberry, Rep. Geol. Surv. Ohio, vol. i. 
pt. ii. (1873), p. 316, pis. xxx., xxxi., and op. cit. (1889), 
p. 64, pi. xxxii. fig. 2. — Huron Shale (Upper Devonian) ; 
Delaware, Ohio. [The type species, founded upon the 
head, with jaws, &c. ; Columbia College (in part).] 

Dinichthys minor, J. S. Newberry, Ann. New York Acad. Sci. 
vol. i. (1878), p. 191, and op. cit. (1889), p. 149, pi. viii. 
figs. 1-8. — Cleveland Shale, Lorain Co., Ohio. [Dorsal 
shield, median occipital, and portions of jaws ; Columbia 
College.] 

Dinichthys newberryi, 0. M. Clarke, Bull. U. S. Geol. Surv. no. 16 
(1885), p. 17, pi. i. fig. 1 .—Hamilton Shale (Upper Devo- 
nian) ; W. New York. [Mandibular ramus ; National 
Museum, Washington.] 



302 A.RTHRODIRA.. 

Dinichthys ? precursor, J. S. Newberry, Palaeoz. Fishes X. America 
(1889), p. 51, pi. xli. — Corniferous Limestone (Lower 
Devonian) ; Sylvania, Ohio. [Median dorsal shield.] 

Dinichthys ringuebergi, J. S. Newberry, op. cit. (1889), p. 60 : 
Dinichthys minor, E. N. S. Ringueberg (non Newberry), 
Amer. Journ. Sci. [3] vol. xxvii. (1884), p. 476, woodc. 
figs. 1, 2. — Portage Group (Lower Carboniferous); Stur- 
geon Point, New York. [Median dorsal shield.] 

Dinichthys terrelli, J. S. Newberry, Rep. Geol. Surv. Ohio, vol. i. 
pt. ii. (1873), p. 322, and ibid, vol.ii. pt. ii. (1875), p. 27, 
charts v., vi., and Palaeoz. Pishes N. America (1889), 
pi. iv. figs. 1, 2 : D. hertzeri, J. S. Newberry {errore), Rep. 
Geol. Surv. Ohio, vol. i. pt. ii. pis. xxxii.-xxxiv. — Huron 
Shale ; Lorain Co., Ohio. [Head, with jaws, &c. This is 
the largest known species, the transverse measurement of 
the occipital region of the cranium being 0*95.] 

(?) Dinichthys tuberculatus, J. S. Newberry, Trans. New York 
Acad. Sci. vol. vii. (1888), p. 179, and op. cit. (1889), 
p. 98, pi. xxxii. fig. 3. — Chemung Group (Upper Devo- 
nian) ; Warren, Pennsylvania, and Ohio. Also recorded 
from Psammite de Condroz, near Liege, Belgium. [Por- 
tions of tuberculated plates.] 

Genus TITANICHTHYS, Newberry. 
[Trans. New York Acad. Sci. vol. v. 1885, p. 27.] 

Plates of head and trunk [except plastron, which is unknown] 
resembling those of Dinichthys, but relatively thinner. Mandibular 
rami without denticulations, long and slender, grooved in the ante- 
rior portion of the oral margin, as if for a horny sheath, and some- 
what turned upwards at the symphysis. 

The two known species of this genus attain a size even greater 
than those of Dinichthys, the cranium measuring not less than 1-25 
across the occipital region. They are described as follows, but are 
not represented in the Collection : — 

Titanichthys agassizi, J. S. Newberry, Trans. New York Acad. 
Sci. vol. v. (1885), p. 27, and Palaeoz. Fishes N. America 
(Mon. U. S. Geol. Surv. no. xvi. 1889), p. 133, pi. i. figs. 
1, 2, pi. ii. figs. 1, 2, pi. iv. fig. 4. — Cleveland Shale 
(Lower Carboniferous); Lorain Co., Ohio. [The type 
species. Head ; Mils. Comp. Zoology, Cambridge, Mass.] 

Titanichthys clarhi, J. S. Newberry, Trans. New York Acad. Sci. 
vol. vi. (1887), p. 164, and Palaeoz. Fishes N. America 






COCCOSTEID-E. 303 

(1889), p. 133, pi. ii. figs. 3, 4, pi. iii. figs. 1-5, pi. iv. 
fig. 3. — Cleveland Shale ; Ohio. [Head, &c. ; Columbia 
College, New York.] 

Genus MACROPETALICHTHYS, Norwood & Owen. 

[Amer. Journ. Sci. [2] vol. i. 1846, p. 371.] 

Syn. Physichthys, H. von Meyer, Palaeontogr. vol. iv. 1855, p. 80. 

Agassichthys, J. S. Newberry, Bull. National Institute, 1857, 
p. 3. 

Cranial shield much arched from side to side, superficially orna- 
mented with stellate tubercles ; sensory canals forming large tubular 
excavations in the bone, opening at the external surface by a con- 
tinuous narrow slit. Elements of cranial shield fused together in 
the adult ; orbits completely surrounded ; parachordal cartilages 
ossified ; [jaws unknown]. 

In the description of this genus by Newberry \ the sensory canals 
are regarded as " double sutures," and the arrangement of the bones 
6till remains to be determined. 

There are no remains of Macropetalichthys in the Collection, but 
the following species have been distinguished : — 

Macropetalichihys agassizi, J. S. Newberry, Eep. Geol. Surv. 
Ohio, vol. i. pt. ii. (1873), p. 291 : Placothorax agassizi, 
H. von Meyer, Neues Jahrb. 1846, p. 596, and Palaeontogr. 
vol. i. (1847), p. 102, pi. xii. fig. 1 : Asterolepis hoening- 
hat(sii, L. Agassiz, Poiss. Foss. Y. G. E. (1845), pp. 130, 
147, pi. xxx. a. fig. 10 : Physichthys hoeninghansii, H. von 
Meyer (in part), Palseontogr. vol. iv. (1855), p. 80, pi. xv. 
figs. 1-5 (nonfigs. 6-11) 2 . — Devonian : Eifel, Germany. 

Macropetcdichthys pruemiensis, E. Kayser, Zeitschr. deutsch. geol. 
Ges. vol. xxxii. (1880), p. 678 (name only). — Lower Devo- 
nian ; Priim, Eifel. [Fragment ; Geol. Surv. Museum, 
Berlin.] 

Macropetalichthys sullivanti,! . S. Newberry, Eep. Geol. Surv. Ohio, 
vol. i. pt. ii. (1873), p. 294, pi. xxiv., pi. xxv. fig. 1, and 
Palaeoz. Fishes N. America (Mon. U. S. Geol. Surv. no. xvi. 



J. S. Newberry, Eep. Geol. Surv. Ohio, vol. i. pt. ii. (1873), p. 290, and 
Palaeoz. Fishes N. America (1889), p. 41. 

* The specimens described by Meyer are preserved in the Museum of Com- 
parative Zoology, Cambridge, Mass., where the present writer has examined 
them. Only the original of figs. 1-5 pertains to Macropetalichthys ; the plate 
shown in fig. 7 being apparently an anterior median dorsal of Pterichthys rhe- 
nanus ; while the original of fig. 9 is a Chimaeroid tooth, and figs. 6, 8, and 10 
are not readily determinable. 



304 ARTMRODIRA. 

1889), p. 44: MacropetalichtJiys rapheidolabis, Norwood 
and Owen, Amer. Journ. Sci. [2] vol. i. (1846), p. 871 : 
Agassichthys sullivanti and A. manni, J. S. Newberry, Bull. 
National Institute, 1857, p. 3 : MacropetalichtJiys manni % 
J. S. Newberry, Amer. Journ. Sci. [2] vol. xxiv. (1862), 
p. 75. — Corniferous Limestone (Lower Devonian) ; Ohio, 
[The type species ; E. D. Cope Collection, Philadelphia.] 

Genus HOMOSTEUS, Asmuss. 

[Das vollkommenste Hautskelet der bisher bekannten Thierreihe 
(Inaug. Dissert. Dorpat, 1856), p. 8 (Homostius).] 

Syn. Asterolepis, L. Agassiz (non Eichwald), Poiss. Foss. V. G. R. 
1845, p. 89 (in part) ; H. Miller (non Eichwald), footprints of 
the Creator, 1849, p. 70 (in part). 

Head and trunk broad, the dorsal aspect flattened ; scutes orna- 
mented with stellate tubercles ; caudal region destitute of armour. 
Occipital elements of cranial shield constituting more than half of 
its length ; orbits completely surrounded, the preorbital and post- 
orbital plates forming the narrow outer bar ; a distinct small median 
bone over the pineal region, not perforated ; mandibular rami sutur- 
allv united at the symphysis, apparently toothless. A single broad 
median dorsal shield upon the trunk, with an inner longitudinal 
keel, and obtuse posteriorly ; two dorso-lateral plates on each side, 
the anterior relatively large, with a well-developed, forwardiy- 
directed, antero-external process, but no prominent condyle for arti- 
culation with the external occipitals. [Ventral armour unknown.] 

The known species of this genus attain a large size, the width of 
the body-shield in H. milleri being not less than 028. 

Homosteus formosissimus, Asmuss. 

1844. Asterolepis, L. Agassiz (non Eichwald), Poiss. Foss. V. G. R. 
p. 96, pi. xxxii. tigs. 2, 9, 10. 

1856. Homostius formosissimus, H. Asmuss, Das vollkommenste Haut- 
skelet der bisher bekannten Thierreihe, p. 35. 

1856. Homostius cataphr actus, H. Asmuss, ibid. p. 36. [Median occi- 
pital ; University Museum, Dorpat.] 

1856. Homostius lotus, H. Asmuss, ibid. p. 36. [Ditto.] 

1856. Homostius ponderosus, H. Asmuss, ibid. p. 37. [Lateral occipital ; 
University Museum, Dorpat.] 

1856. Homostius anceps, H. Asmuss, ibid. p. 39. [Bones ; University 
Museum, Dorpat.] 

1857. Homostius, C. H. Pander, Placoderm. devon. Svst. p. 74. pi. viii. 
figs. 2, 6, 7. 






COCCOSTEIDJE. 305 

18G0. llomostius latus, E. von Eichwald, Leth. Rossica, vol. i. p. 1519, 
pi. lvi. fig-. 2. 



Type. Portion of median dorsal plate ; University Museum, 
Dorpat. 

The type species, known only from separately discovered bones 
Median dorsal plate broader behind than in front, the posterior 
margin only slightly convex ; forwardly directed process of anterior 
dorso-lateral plate slender and pointed. 

Form. <$f Log. Lower Devonian : Livonia, and near PawlowsK, 
Government of St. Petersburg. 

The following are plaster casts of the original bones from Livonia 
in the University of Dorpat, and were presented by Sir Roderick I. 
Murchison, K.C.B., about 1846. 

15142 a. The type specimen, being the middle and right lateral 
portions of the median dorsal plate, wanting all margins 
except the posterior ; described by Asmuss {op. cit. p. 35. 
no. 5) as " scutum dorsale anterius," and the posterior 
border regarded as anterior. 

15142 b. Imperfect left anterior dorso-lateral (Pander, fig. 2 11 ), de- 
scribed by Asmuss (p. 36, no. 35) as right " adminiculum 
laterale " of H. formosissimus. 

15142 c. Left postorbital (Pander, fig. 2 5 , Agassiz, fig. 2), described 
by Asmuss (p. 38, no. 36) as right " os incunneatum " of 
H. latus. 

15142 d. More imperfect example of the same bone, showing the 
postero-lateral extension. 

15142 e. Middle and right lateral portion of hinder half of median 
occipital, the type specimen of H. latus, Asmuss (p. 36, 
no. 6), and described as left anterior portion of the " scutum 
dorsale posterius." 

15142 f. Middle portion of median occipital, the type specimen of 
H. cataphractus, Asmuss (p. 36, no. 7), and determined as 
" scutum dorsale posterius." 

15142 g. Half of median occipital, and portion of adjoining left 
lateral occipital, probably the basis of Pander's partial 
restoration (fig. 2 9 ' i0 ) ; described by Asmuss (p. 37, no. 32) 
as right " os multifixum " with " scutum dorsale poste- 
rius " of H. cataphractus. 

15142 h. Outer portion of left lateral occipital, probably employed 

PAKT II. x 



306 ARTHRODIRA. 

in Pander's partial restoration (fig. 2 9 ) ; ? Asmuss, no. 31 
(" os multifixum " of H. formosissimus), p. 37. 

15142 i. Posterior portion of left lateral occipital, the type speci- 
men of H. ponderosus, Asmuss (p. 37, no. 33), described 
as right " os multifixum." 

15142 z. Two undetermined hones (Agassiz, pi. xxxii. figs. 9, 10) ; 
the type specimens of H. anceps, Asmuss (p. 39, no. 28). 



Homosteus miller i, Traquair. 

1849. ll Asterolepis of Stromness," H. Miller (non Aste?-olepis,'Eichw'dld), 
Footprints of the Creator, p. 70, woodc. figs. 24, 27-29, 36, 37, 
39-41 (? figs. 34, 35, 38, 44, non figs. 25, 26, 30-33, 42). 

1854. Asterolepis asmusii, J. Morris (non Agassiz), Catal. Brit. Foss. 
2nd ed. p. 318. 

1857. Homostius, C. H. Pander, Placoderm. devon. Syst. p. 74, pi. viii. 
figs. Sa-c. 

1860. Homostius, sp. nov., E. von Eichwald, Leth. Eossica, vol. i. 
p. 1520. 

1869. Asterolepis, J. Miller, Geol. Mag. vol. vi. p. 384. 

1888. Homosteus milleri, R. H. Traquair, Geol. Mag. [3] vol. v. p. 511, 

1889. Homosteus milleri, R. H. Traquair, ibid. vol. vi. p. 1, pi. i. fig. 1. 

Type. Cranial shield ; Edinburgh Museum. 

A species sometimes equalling H. latus in size. Median occipital 
tapering forwards, its anterior border less than half as wide as the 
posterior ; external occipital twice as long as its maximum breadth. 
Median dorsal plate narrower behind than in front, the posterior 
margin obtusely angulated in the middle; ornamented portion of 
anterior dorso-lateral twice as long as broad, and the forwardly- 
directed process somewhat spatulate ; posterior dorso-lateral rela- 
tively very small, triangular in form, with the hinder apex deflected 
inwards. 

Form. Sf Log. Lower Old Red Sandstone : Caithness and Orkney. 

P. 5539. Plaster cast of the head and trunk, showing the boundaries 
and arrangement of the dorsal plates, and some of the 
displaced jaw-bones, &c. : Thurso. The original specimen 
is preserved in the Museum of Science and Art, Edinburgh, 
and is described and figured by Traquair. loc. cit. 1889. 
The figure is reproduced in the accompanying woodcut 
(fig. 46), and explained by the lettering. 

Presented by the Lords of the Committee 
of Council on Education, 1888. 



COCCOSTEIDJS. 



307 



P. 5540. Plaster cast of a similar but more imperfect specimen, with 
displaced median dorsal plate ; Thurso. The original is 
also preserved in the Museum of Science and Art, Edin- 
burgh. Presented by the Lords of the Committee 
of Council on Education, 1888. 



Pig. 46. 




Homosteus milleri, Traq. — Outline of cranial and dorsal shield, by E. H. Tra- 
quair, one-sixth nat. size, a, b, c, undetermined bones ; a.d.L, anterior 
dorso-lateral ; a.e., ethmoid ; c, central ; e.o., external occipital ; m., mar- 
ginal ; m.d., median dorsal ; m.o., median occipital ; o., orbit ; p.d.l., 
posterior dorso-lateral ; jp.o., preorbital; jpt.e., pineal ; pt.o., postorbital. 



P. 698. Series of seven plaster casts of specimens in the Hugh 
Miller Collection, Edinburgh Museum, five being figured 
by Miller, op. cit. figs. 27, 28, 35, 39 ; Orkney. 

Egerton Coll, 

P. 699. Imperfect median dorsal plate measuring, in its broken con- 
dition, 0-28 across; Orkney. Egerton Coll. 

P. 3227. Portion of dermal plate, showing stellate tubercular orna- 
ment ; Orkney. EnnisJdllen Coll. 

x2 



308 AETHRODIRA. 



Genus HETEROSTEUS, Asmuss. 

[Das vollkommenste Hautskelet der bisher bekannten Thierreihe 
(Inaug. Dissert. Dorpat, 1856), p. 7 {Heterostius).'] 

Syn. Ichthyosauroides, S. Kutorga, Zweiter Beitr. Geogn. u. Palaont. 

Dorpat's, 1837, p. 35 (inappropriate). 
Chelonichthys, L. Agassiz, Poiss. Foss. vol. i. 1844, p. xxxiii. 

(name only, in part). 
Asterolepis, L. Agassiz (non Eichwald), Poiss. Foss. V. G. R. 

1845, p. 89 (in part). 

A genus of enormous size, closely allied to Homosteus, but known 
only from detacbed dermal bones. Head and trunk broad, the dorsal 
aspect flattened ; scutes ornamented with large stellate tubercles, 
and those of the upper surface of the head also marked with deep 
sensory furrows. A single broad median dorsal shield upon the 
trunk, with an inner longitudinal keel, and more or less acutely 
pointed posteriorly ; the anterior dorso-lateral plate on each side 
with a very large, forwardly-directed, antero-external process, and a 
prominent condyle for articulation with the external occipital. 



Heterosteus asmussi (Agassiz). 

1837. Trionyx spinosus, S. Kutorga, Zweiter Beitr. Geogn. u. Palaont. 

Dorpat's, p. 9, pi. i. 
1837. Humerus Trionychis, S. Kutorga, ibid. p. 17, pi. viii. fig. 1. 
(?) 1837. Trionyx miliaris, S. Kutorga, ibid. p. 16, pi. vii. fig. 4. 

1844. Chelonichthys asmusii, L. Agassiz, Poiss. Foss. vol. i. p. xxxiii. 
(name only). 

1845. Asterolepis asmusii, L. Agassiz, Poiss. Foss. V. G. R. pp. 92, 
146, pi. xxx. fig. 1, pi. xxx. a. fig. 11. 

1845. Asterolepis, L. Agassiz (non Eichwald), ibid. p. 94, pi. xxxii. 

figs. 7, 11-13, 15-19. 
1856. Heterostius hueckii, H. Asmuss, Das vollkommenste Hautskelet 

der bisher bekannten Thierreihe, p. 28. [Median dorsal plate ; 

University Museum, Dorpat.] 
1856. Heterostius gracilior, H. Asmuss, ibid. p. 28. [Ditto.] 
1856. Heterostius convexus, H. Asmuss, ibid. p. 28. [Ditto.] 
1856. Heterostius eurynotus, H. Asmuss, ibid. p. 28. [Ditto.] 
1856. Heterostius ingens, H. Asmuss, ibid. p. 29. [Median occipital ; 

University Museum, Dorpat.] 
1856. Heterostius secundarius, H. Asmuss, ibid. p. 30. [Anterior 

dorso-lateral ; University Museum, Dorpat.] 

1856. Heterostius initialis, H. Asmuss, ibid. p. 31. [Ditto.] 

1857. Heterostius, C. H. Pander, Placoderm. devon. Syst. p. 82, pi. viii. 



COCCOSTEHLE. 309 

18C0. Heterostius eurynotus, E. von Eichwald, Leth. Rossica, vol. i. 
p. 1524. 

Type. Fragment of dermal armour. 

The type species, of very large size, known only from separately- 
discovered bones. Forwardly-directed process of anterior dorso- 
lateral more than twice as long as the remainder of the bone. 
Ornamentation sparse. 

Form. <$f Log. Lower Devonian : Livonia. 

The following are plaster casts of the original bones from Livonia 
in the University of Dorpat, described by Asmuss, and were pre- 
sented by Sir Roderick I. Murchison, K.C.B., about 1846 : — 

15142 j. Imperfect median dorsal plate, shown from the inner 
aspect and the posterior margin placed uppermost by 
Agassiz (op. cit. pi. xxxii. fig. 13) ; the type specimen of 
H. huechii, Asmuss (op. cit. p. 28, no. 1), described as 
" scutum dorsale anterius." 

15142 k. Fragment of middle portion of a similar plate (Agassiz, 
pi. xxxii. fig. 8); the type specimen of H. gracilior, 
Asmuss (p. 28, no. 2). 

15142 1. Anterior portion of inner keel of median dorsal shield ; 
the type specimen of H. conveccus, Asmuss (p. 28, no. 3). 

15142 m. Fragment of median dorsal shield (Agassiz, pi. xxxii. 
figs. 11, 12); the type specimen of H. eurynotus, Asmuss 
(p. 28, no. 4). 

15142 n. Imperfect right anterior dorso-lateral (Agassiz, pi. xxxii. 
fig. 19); described by Asmuss (p. 30, no. 19) as " admi- 
niculum laterale " of H. eurynotus. 

15142 0. Similar bone, less imperfect, but scarcely more than half 
as large as the latter (Agassiz, pi. xxxii. fig. 18, Pander, 
pi. viii. fig. 1") ; described by Asmuss (p. 30, no. 18) as 
H. conveocus. 

15142 p. Fragment of process of similar bone; assigned to H. in- 
gens by Asmuss (p. 30, no. 20). 

15142 q.. Expanded portion of a similar bone, left side : the type 
specimen of H. secundarius, Asmuss (p. 30, no. 22). 

15142 r. Similar specimen, showing overlapping fragments poste- 
riorly ; the type specimen of H. initiate, Asmuss (p. 31, 
no. 25). 



310 ARTHRODIRA.. 

15142 S. Imperfect median occipital, shown from the inner aspect 
and the posterior margin placed uppermost by Agassiz 
(pi. xxxii. fig. 7), and figured 03- Pander {op. cit. pi. viii. 
fig. I 10 ) ; the type specimen of H. ingens, Asmuss (p. 29, 
no. 9), described as " scutum dorsale posterius." 

15142 t. Eight lateral occipital (" mastoid " or marginal, Pander, 
pi. viii. fig. I 9 ), figured by Agassiz (pi. xxxii. figs. 15, 
16), the glenoid extremity being placed uppermost ; 
described by Asmuss (p. 32, no. 16) as " os multifixum " 
of H. eurynotus. 

15142 U. Portion of similar bone; assigned by Asmuss (p. 32, 
no. 15) to H. gracilior. 

15142 V. Bone figured by Agassiz (pi. xxxii. fig. 17) and identified 
by Pander (pi. viii. fig. I 5 ) with the anterior extremity 
of the postorbital; described by Asmuss (p. 32, no. 38) 
as left " os incunneatum " of H. convexus. 

15142 W. Portion of bone identified by Pander (pi. viii. fig. I 3 ) 
with the hinder half of the postorbital ; described by 
Asmuss (p. 32, no. 17) as upper half of left " os inter- 
jectum." 

The right half of a median dorsal plate of Heterosteus, from 
Dorpat, is described by S. Kutorga 1 as the coracoid of a genus of 
reptiles, Ichthyosauroides, allied to Ichthyosaurus. This is regarded 
as the type of a distinct species of Heterosteus, H. kutorgce, by 
Asmuss (op. dt. p. 29), and the original of the first of the under- 
mentioned plaster casts is also assigned to it. 

15142 x. Hinder middle portion of small median occipital (" scutum 
dorsale posterius," Asmuss, p. 29, no. 8), probably refer- 
able to young individual of H. asmussi; original from 
Dorpat. 
Presented by Sir Roderick I. Murchison, K.C.B., about 1846. 

15142 y. Portion of left half of a similar bone, assigned to H. con- 
vexus by Asmuss (p. 29, no. 10) ; original from Dorpat. 
Presented by Sir Roderick I. Murchison, K.C.B., about 1846. 

Several bones found associated with those of Homosteus and He- 
terosteus in the Lower Devonian of Livonia are also represented in 
the Collection by plaster casts, presented by Sir Roderick I. 3Iur- 

1 Zweiter Beitr. Geogn. u. Palaont. Dorpat's, 1837, p. 35, pis. v., vi. 



COCCOSTEIDiE. 



311 



chison, K.C.B., about 1846, and entered under the general number 
15142. Five are figured by Agassiz (Poiss. Foss. V. G. R. pi. xxxii. 
figs. 3-6, 14), and a few are regarded by the same author (ibid. 
p. 94) as referable to Asterolcpis minor. Two are of the form 
named Trionyx sulcatus, S. Kutorga, Beitr. Geogn. u. Palaont. 
Dorpat's, ii. (1837), p. 13, pi. ii. figs. 1-4, and resemble the speci- 
men from the Lower Old Red Sandstone of Thurso determined as 
" Shoulder (i. e. coracoid ?) plate of Asterolepis " by Hugh Miller, 
" Footprints of Creator " (1849), p. 88, woodc. fig. 38. 

A single slab of Cleveland Shale (Lower Carboniferous), dis- 
covered by Dr. William Clark in the bank of the Rocky River, 
below Berea, Ohio, and now in the Museum of Columbia College, 
New York, seems to pertain to a genus of Coccosteidae distinct from 
all described above. The fish is characterized by very slender, pro- 
minently denticulated mandibular bones, a ring of four sclerotic (?) 
plates, and a scute-ornament of large, high, conical tubercles. It 
is named Trachosteus ciarJci, J. S. Newberry, Palaeoz. Fishes N. 
America (Mon. U.S. Geol. Surv. no. xvi. 1889), p. 167, pi. xlii. 
figs. 1-8. 

Other large detached dermal plates, perhaps for the most part 
referable to this family, are also described as follows : — 

Aspidichihys, J. S. Newberry, Rep. Geol. Surv. Ohio, vol. i. pt. ii. 
(1873), p. 322, with the type species, A. clavatus, Newberry, ibid. 
p. 323, pi. xxxv. figs. 1, 2, from the Huron Shale (Upper Devonian) 
of Delaware, Ohio. [Columbia College, New York.] Also A. ? in- 
gens, A. von Koenen, Abh. phys. CI. k. Ges. Wiss. Gottingen, vol. 
xxx. (1883), p. 34, pi. iii. fig. 1, pi. iv. fig. 4, from the Upper 
Devonian of Martenberg, near Adorf, and Charlottenzug, near 
Bredelar, N. Germany [Royal Geological Museum, Gottingen] ; and 
perhaps the so-called Coccosteus fritschi, Barrande (see p. 294). 

Anomalichthys, A. von Koenen, Abh. phys. CI. k. Ges. Wiss. 
Gottingen, vol. xxx. (1883), p. 38, with the type species, A. scaber, 
A. von Koenen, ibid. p. 38, pi. iii. fig. 2, from the Upper Devonian 
of Martenberg, near Adorf. [Royal Geological Museum, Gottingen.] 
Drepanaspis, C. Schliiter, Sitzungsb. niederrhein. Ges. Bonn, 
1887, p. 126, with the type species, D. gemuendenensis, Schliiter, 
ibid. p. 126. — Lower Devonian ; Gemiinden, Eifel. [Bonn Univer- 
sity Museum.] 

Glyptaspis, J. S. Newberry, Palaeoz. Fishes N. America (1889), 
p. 157, with the type species, G. verrucosa, Newberry, ibid. p. 158, 
pi. xiii. figs. 1, 2, from the Cleveland Shale (Lower Carboniferous) 
of Ohio. [Columbia College, New York.] 

Lophostracon spitzbergense, E. R. Lankester, Kongl. Svenska 



31 2 ARTHRODIRA. 

Vetensk.-Akad. Handl. vol. xx. no. 9 (1884), p. 5, pi. ii. fig. 6. — 
Lower Devonian ; Dickson Bay, Spitzbergen. [Royal State Museum, 
Stockholm.] 

The hinder portion of the head evidently of one of the Coccosteidao, 
from the Devonian of the Government of Orel, Russia, has also been 
described under the name of Siphonodus panderi, G. Fischer do 
Waldheim, Bull. Soc. Imp. Nat. Moscou, vol. xxv. (1852), pt. i. 
p. 175, pi. iii. figs. 1-3. In this specimen, the ossified parachordal 
cartilage is seen, with the tubular canal originally occupied by the 
anterior extremity of the nofcochord. 

The singular mandibular rami, described as follows, may also 
pertain to this family : — 

Diplognathus mirabilis, J. S. Newberry, Ann. New York Acad. 
Sci. vol. i. (1878), p. 188, and Trans. New York Acad. 
Sci. vol. v. (1885), p. 27, and Palseoz. Fishes N. America 
(Hon. U.S. Geol. Surv. no. xvi. 1889), p. 159, pi. xi. 
figs. 1-4, pi. xii. figs. 1-3. — Cleveland Shale ; Lorain Co., 
Ohio. [Columbia College, New York.] 



Family ASTEROSTEIDjE. 

An imperfectly known family, as yet incompletely definable. 
Nasal openings large and mesially placed, scarcely, if at all, in 
advance of the orbits. 

Genus ASTEROSTSUS, Newberry. 
[Rep. Geol. Surv. Ohio, vol. ii. pt. ii. 1875, p. 35.] 

A genus comprising species of small size, known only by the 
cranial shield. Head long and narrow, flattened, having the con- 
stituent elements fused in the adult ; orbits placed far forwards and 
forming broad notches, between which is a pair of large, oval nasal 
openings ; a pineal foramen somewhat more posteriorly. Cranial 
roof ornamented with large, rounded, stellate tubercles, very irre- 
gular in size and arrangement. 

This diagnosis is based upon a personal examination of the 
specimens in the Columbia College, New York, and the American 



PHYLL0LEPID2E. 313 

Museum of Natural History. A single species is described as follows, 
but there are no examples in the Collection : — 

Asterosteus stenoceplialus, J. S. Newberry, Rep. Geol. Surv. Ohio, 
vol. ii. pt. ii. (1875), p. 36, pi. liv. fig. 1, and Palaeoz. 
Fishes N. America (Mon. U.S. Geol. Surv. no. xvi. 1889), 
p. 45, pi. xxx. fig. 1. — Corniferous Limestone (Lower 
Devonian) ; Sandusky and Delaware, Ohio. [Cranial 
shield ; Columbia College.] 



Family PHYLLOLEPIDiE. 

An imperfectly definable family, of uncertain position, probably 
related to the Coccosteidae. Dermal plates very thin, and marked 
by a superficial ornament of rugae, more or less following the con- 
centric or radiating lines of growth. 

Synopsis of Genera. 

Superficial rugae concentric .... Phyllolepis (p. 313). 
Superficial rugae radiating Holonema (p. 314). 

Genus PHYLLOLEPIS, Agassiz. 
[Poiss. Foss. V. G. R. 1844, p. 67.] 

Dermal plates concentrically marked with more or less irregular 
and wavy rugae. 

These problematical fossils have hitherto only been found isolated, 
and are rarely met with unbroken. By most palaeontologists they 
are associated with the Holoptychian Crossopterygii, while Fritsch 
has compared them with head-bones of Palaeozoic Dipnoi. We 
venture, however, to adopt the suggestion of Newberry that the 
plates are truly referable to some so-called " Placoderm," though 
we would compare them with Coccosteus and its allies rather than 
with Pterichthys. 

If the last-named suggestion prove correct, this genus will also 
include the small dermal plates from the Psammites of Condroz 
(Upper Devonian), Belgium, named Pentagonolepis Tconincki, M. 
Lohest, Ann. Soc. Geol. BeJg. vol. xv. (1888), p. 161, pi. xi. 
figs. 1-8. Moreover, the form of the dermal plates cannot be cited 
in specific diagnoses until their arrangement and homologies have 
been determined. 



314 ARTHEODIRA. 

Phyllolepis concentrica, Agassiz. 

1844. Phyllolepis concentricus, L. Agassiz, Poiss. Foss. V. G. R. p. 67, 

pi. xx iv. fig. 1. 
1862. Phyllolepis concentricus, W. Davies, Geologist, vol. v. p. 458. 
1888. Phyllolepis concentricus, A. Fritsch, Fauna der Gaskohle, vol. ii. 

p. 89, woodc. fig. 169. 

Type. Imperfect dermal plate ; unknown. 

The type species, of large size. Superficial rugae coarse, rounded 
or slightly angulated, somewhat wavy, and separated by spaces two 
or three times their own width. 

Form. Sf Loo. Upper Old lied Sandstone : Perthshire and Fife- 
shire. (?) Devonian : Meadsfoot, Torquay. 

P. 3292. Specimen measuring 0*095 in its longest diameter, so far 
as preserved, and having one long border obtusely angu- 
lated ; Dura Den, Fifeshire. The fossil must have been 
gently convex, but it occurs chiefly as a concave impres- 
sion, from which is taken the plaster cast figured by A. 
Fritsch, loc. cit. Ennishillen Coll. 

P. 5096. Fragment of plate ; Clashbennie, Perthshire. 

Presented by John Edward Lee, Esq., 1885. 

Other plates of this genus have been described under the follow- 
ing names : — 

Phyllolepis delicatula, J. S. Newberry, Palaeoz. Fishes N". America 
(Mon. U. S. Geol. Surv. no. xvi. 1889), p. 97, pi. xix. 
fig. 11. — Chemung Group (Upper Devonian); Bradford 
Co., Pennsylvania. 

Phyllolepis corneti, M. Lohest, Ann. Soc. Geol. Belg. vol. xv. 
(1888), p. 157, pi. x. fig. 6. — Upper Devonian ; Strud and 
Chevreniont, Belgium. [M. Lohest Collection, Liege.] 

Phyllolejjis undulata, M. Lohest, ibid. p. 157, pi. x. figs. 3-5, 
pi. xi. fig. 9. — Upper Devonian ; Strud, Chevremont, and 
Evieux, Belgium. [M. Lohest Collection.] 



Genus HOLONEMA, Newberry. 
[Palaeoz. Fishes N. America, 1889, p. 92.] 

Dermal plates marked with irregularly branching, radiating rugae. 
The form of the median ventral plate of this genus (figured by 



MTLOSTOMATID^!. 315 

Newberry, op. cit. pi. xvii. fig. 2) more closely resembles that of 
certaiu species of Coccosteus (e. g. C. disjectus, p. 292) than the 
corresponding plate of the Asterolepidae ; and the recent description 
of the complete ventral shield by Claypole (Amer. Geologist, 1890, 
p. 255, with fig.) proves that it agrees with that of Coccostetis in 
every essential particular. The " post-dorso-median " plate of 
Claypole is obviously the anterior median ventral, while the "post- 
dorso-lateral " and " dorso-lateral " of the same author are the 
anterior and posterior ventro-lateral plates respectively. 

There are no examples of this genus in the Collection, and only a 
single species has as yet been recognized, thus : — 

Holonema rugosum, J. S. Newberry, op. cit. p. 93, pi. xvii. figs. 1-4 : 
Pterichthys (?) rugosus, E. W. Claypole, Prod Amer. Phil. 
Soc. vol. xx. (1883), p. 666, with fig. : Pterichthys (Bothrio- 
lepis) rugosus or Holonema rugosum,- E. W. Claypole, 
Amer. Geologist, 1 890, p. 257, with fig. — Chemung Group 
(Upper Devonian) ; New Jersey and N. Pennsylvania. 
Catskill Group (Upper Devonian); New York State. 
[Median ventral plate ; Museum of Akron College, Ohio.] 

So far as can be determined from the description and imperfect 
figures, the dermal plates from the Devonian of the Eifel, named 
Coccosteus obtusus, Koenen (see p. 294), exhibit much resemblance 
to those of Holonema. 



Family MYLOSTOMATID.E. 

An imperfectly known family, as yet incompletely definable. 
Dentition consisting of a paired series of few large, dense, tritu- 
rating plates in each jaw. 



Genus MYLOSTOMA, Newberry. 
[Trans. New York Acad. Sci. vol. ii. 1883, p. 145.] 

The type genus, known only by the teeth and the bones of the 
mandible. Principal dental plates triangular or spatulate in form, 
flattened or with an irregularly tumid coronal surface, which is 
more or less nearly parallel with the attached surface. Dentigerous 
bone of the lower jaw exhibiting a much-expanded oral border for 
the support of the teeth. 

This genus is not represented in the Collection, and has only been 



316 TELEOSTOMl. 

discovered hitherto in the Lower Carboniferous of the United States. 
Two species are recognized, the type specimens being preserved in 
the Museum of Columbia College, New York. 

Mylostoma terrelli, J. S. Newberry, Trans. New York Acad. Sci. 
vol. ii. (1883), p. 147, and Palaeoz. Fishes N. America 
(1889), p. 164, pi. xiv. figs. 1, 2.— Cleveland Shale ; Erie 
Co., Ohio. 

Mylostoma variabiles J. S. Newberry, ibid. (1883), p. 146, and 
ibid. (1889), p. 165, pi. xv. figs. 1-5, pi. xvi. figs. 1-4 — 
Cleveland Shale ; Sheffield, Ohio. [The type species.] 

Possibly in this family may also be placed the tooth from the 
Devonian of the Eifel, named Typodus glaber, H. von Meyer, Palae- 
ontogr. vol. i. (1847), p. 102, pi. xii. fig. 2. 



Subclass V. TELEOSTOMl. 

Skeleton more or less ossified, with well-developed membrane- 
bones : margin of jaw with membrane-bones above and below. 
Mandibular suspensorium articulated with the cranium ; gill-clefts 
feebly separated, opening into an external cavity covered by a bony 
operculum. Membrane-bones of pectoral arch connected with those 
of the occiput. Exoskeleton, when present, consisting of true bone 
or delicate, superposed, calcified lamellae. In the living forms — 
ovaries with numerous small ova. 



Order I. CEOSSOPTERYGII. 

Paired fins lobate, having an endoskeletal axis, more or less 
fringed with dermal rays ; caudal fin diphycercal or heterocercal. A 
pair of large jugular plates, sometimes with small lateral plates and 
an anterior azygous element, developed in the branchiostegal 
membrane between the mandibular rami. In the living forms — 
optic nerves not decussating, but forming a chiasma; intestine with 
a spiral valve. 



TARRASIID^:. 317 



Suborder I. HAPLISTIA. 

Notochord more or less persistent. Axonosts and baseosts of 
median fins in simple regular series, much fewer in number than 
the dermal fin-rays. 

Only one specialized family is provisionally placed here, that 
of the Tarrasiidaa. 



Family TARRASIID^. 

Membrane-bones of head and opercular fold well developed. 
Pectoral fins obtusely lobate ; tail diphy cereal, with a continuous 
dorso-caudal fin; median fin-supports more numerous than the 
vertebral arches. 

The pelvic fins remain unknown. 

Genus TARRASIUS, Traquair. 
[Trans. Roy. Soc. Edinb. vol. xxx. 1881, p. 61.] 

Trunk elongated, laterally compressed ; head small, its external 
bones superficially coated with ganoine. Anal fin continuous with 
the caudal. Caudal region enveloped in very small, thick, quad- 
rangular, ganoid scales, which scarcely overlap but are closely 
arranged. 

Tarrasius problematicus, Traquair. 

1881. Tarrasius problematicus, R. H. Traquair, he. cit. p. 62, pi. iv. 

figs. 4-6. 
1890. Tarrasius problematicus, R. H. Traquair, Ann. Mag. Nat. Hist. 

[6] vol. vi. p. 494. 

Type. Imperfect fishes; Geological Survey of Scotland, Edin- 
burgh. 

The type species, of small size, attaining a maximum length of 
about 0*06, in which the head with opercular apparatus is contained 
from five to six times. Scales superficially marked with a median 
depression. 

Form. 4" Loc. Calciferous Sandstones (Cement-stone Group) : 
Giencartholm, Eskdale, Dumfriesshire. 

P. 4704 Two fragmentary specimens, one being in counterpart. 

Purchased, 1883. 



318 CROSSOPTERYGII. 

Suborder II. RHIPIDISTIA. 

Notochord more or less persistent. Axonosts of each of the 
dorsal and anal fins fused into a single piece ; baseosts much fewer 
than, and overlapped by, the dermal rays in all the median fins. 

Synopsis of Families, 

I. Pectoral fins acutely lobate. 
Vertical infoldings of the walls of the 

teeth very numerous and complex 

(' dendrodont ') ; scales cycloidal . . Holoptychiidje (p. 321). 

II. Pectoral fins obtusely lobate. 
Vertical infoldings of the walls of the 

teeth comparatively few and simple ; 

scales cycloidal RmzoDONTiDiE (p. 341 J. 

Walls of teeth only slightly infolded at 

the base ; scales rhomboidal Osteolepidje (p. 367). 

III. Incertae Sedis. 

Tooth -structure simple; a dentigerous 
presymphysial bone ; scales cy- 
cloidal Onychodontidje (p. 391). 

The osteology of some members of each of the three typical 
families of Ehipidistia is now tolerably well known, as the result 
especially of researches by Pander, Huxley, and Traquair. There 
is a remarkable uniformity in the arrangement of the bones and 
fins, and a brief summary of the chief structural features may be 
presented as follows. 

The cranial cartilage is in some degree ossified, but the precise 
arrangement and extent of nearly all the tracts remain still 
unknown. It suffices to remark that in Megalichthys (Ectosteo- 
rhachis) the parachordal cartilages are ossified in the form of a pair 
of large, subtri angular expansions, which unite mesially and 
embrace the notochord in a groove, which is roofed behind but open 
anteriorly \ The whole of the cranium, however, is covered with 
thick dermal plates, which exhibit a definite symmetrical disposi- 
tion except towards the extremity of the rostrum ; and there is, 
similarly, a considerable development of membrane-bones on the 
roof of the mouth. The shield of the cranial roof is divided by a 
much-pronounced, transverse suture into a parietal and frontal 
moiety, the latter being usually the smaller, and excavated on each 
side to form the upper border of the orbit. The parietal portion of 
the shield consists chiefly of a long, narrow pair of parietal bones, 

i E. D. Cope, Proc. Amer. Phil. Soc. vol. xx. (1883), p. 628. 



RHIPIDISTIA. 



319 



extending its whole length, flanked by a pair of squamosal elements 
in the hinder half, and usually also by a pair of postfeontal plates 
in front of these. The posterior half of the frontal shield is formed 
by the frontal bones, which extend from side to side, and are some- 
times fused together in the middle line, with or without a median 
(pineal) foramen ; the anterior extremity of the shield consists of 

Fig. 47. 




Ehizodopsis sauroides (Williamson). — Outlines of head and opercular appa- 
ratus, after Traquair. A. Side view. B. Upper aspect. C. Inferior aspect. 
ag, angular ; d, dentary ; /,frontal ; i.d, infradentary ;j, principal jugular ; 
l.j, lateral jugular ; m.j, median jugular ; mx, maxilla ; mn, mandible ; 
op, operculum; or, orbit; p.f, postf'rontal ; p.mx, premaxilla ; p.op, 
preoperculum ; pa, parietal; s.o, suborbital: s.op, suboperculum ; s.t, 
supratemporal ; sg, squamosal; a-, cheek-plate ; x', (?)jugal. 



the dentigerous prem axillae, usually fused together, and also more 
or less in connection with the irregular small dermal plates which 
intervene between them and the frontals. The cheek is entirely 
covered with loose plates, of which the suborbitals behind and 



320 CROSSOPTERYGII. 

below the eye are conspicuous; the dentigerous maxilla bounds 
these below, and exhibits a small (apparently jugal) plate behind its 
posterior expansion. The latter element extends far backwards, 
and immediately above it is a very large cheek-plate covering the 
whole of the space between the posterior suborbitals, the cranial 
roof, and the preoperculum. On the roof of the mouth there is a 
well-ossified parasphenoid, meeting in front a pair of vomers, each 
of which bears a powerful tooth ; and there are some traces of an 
inward palatal extension both of the maxillae and premaxillae. 

The mandible is very complex and seems to possess a distinctly 
ossified articular element. The dentary bone is relatively deep and 
thick at the symphysis, tapering backwards, and bears a series of 
small teeth, with a single large laniary in front. The lower 
border is bounded by a series of three or four, plate-like, lenticular 
bones, of which the hindermost seems to correspond to the angular, 
while the others are conveniently termed infradentaries. A thin 
splenial lamina forms the inner wall of the ramus, and between this 
and the dentary is arranged a series of about three or four very 
stout lenticular bones, each of which bears a laniary tooth. 

A deep and narrow preoperculum is observed behind the cheek- 
plates, while the operculum and suboperculum are well developed ; 
there is, however, no representative of an interoperculum. Below 
the suboperculum a long narrow plate forms the hinder element of 
the series of lateral jugulars on each side ; and a pair of very large 
principal jugular plates, with or without a small anterior azygous 
element, occupies the whole of the space between these series. 

The cranial roof is bordered behind by three small supratemporal 
plates, one median and a pair lateral ; but there appear to be no 
large scales on the posterior margin of the pectoral arch. Behind 
this, so far as known, the squamation is always continuous; and 
the only enlargement of the scales is observed occasionally at the 
bases of the fins and in the anal region. There are rarely indi- 
cations of a peg-and-socket articulation of the scales, although the 
inner rib is usually conspicuous in those that are rhomboidal, while, 
except in the Holoptychiidae, this rib is represented by a median boss 
in the more deeply overlapping scales of cycloidal form. In one 
genus (Megalichihys) the scale-arrangement proves the anus to have 
been placed at some distance in advance of the anal fin, and not 
quite in the mesial line. 

A lateral line arising immediately above the operculum traverses 
a longitudinal series of scales as far as an undetermined point on the 
caudal pedicle ; and, at least in the Holoptychiidae, there is another 
similar line arising from the jugular plates of either side. In the 



HOLOPTYCHIID^, 321 

Holoptychiidre the sensory canal-system seems to form merely 
grooves in the exoskeleton ; while in the Rhizodontida) and Osteo- 
lepidae it usually perforates the bones, and is especially conspicuous 
upon parts of the head from the series of dot-like apertures by 
which the closed canals open externally. 

The notochord seems to have been always more or less persistent, 
but the cartilages of the arches are at least superficially calcified, and 
in the more specialized genera there occur robust, closely arranged 
ring-vertebrse. 

The pectoral arch exhibits two well-developed pairs of membrane - 
bones — a large clavicle and a smaller infraclavicle, sometimes very 
firmly united by an upward process of the latter. A supraclavicular 
element has also been observed, but there is no definite information 
as to its precise characters. The lobe of the paired fins is supported 
by endoskeletal cartilage, arranged on the plan termed archiptery- 
gial by Gegenbaur : and it is interesting to note that even in the 
short, obtusely lobate fins, the axis is merely shortened and the 
parameres of one side somewhat atrophied, while those of the other 
side are enlarged. There is thus no dibasal or tribasal arrangement 
of the cartilages such as characterizes the pectoral fins of Polypterus. 

In the median fins, the rays are always delicate and very 
numerous, overlapping the ends of the supporting cartilages, which 
are robust and comparatively few in number. The dorsal and anal 
fins always exhibit more or less lobation, and are supported by two 
series of cartilages, the proximal conveniently termed axonosts, and 
the distal baseosts. There is but a single, club-shaped axonost to 
each of the fins, the broad distal end of this element bearing about 
three to six elongated, rod-like baseosts, which are sometimes 
jointed at intervals and bifurcating. The arrangement of the 
supports of the caudal fin is not clearly ascertained. 



Family HOLOPTYCHIID^]. 

Body fusiform, with cycloidal, deeply-overlapping scales, more or 
less enamelled. Head and opercular apparatus with well- developed 
membrane-bones : parietals large and separate : frontals separate, 
not fused into a continuous plate with the adjoining elements ; no 
parietal or frontal foramen ; interoperculum absent ; jugular plates 
comprising one large pair, flanked on either side by a lateral series. 
Dentary bone of mandible thin and deep, bearing a series of small 
teeth, and with well-developed infradentaries, much bent inwards 
below ; an inner series of few, large, broad, shuttle-shaped bones, 

PART II. T 



322 



CROSSOPTEKYGII. 



each supporting a ' laniary ' tooth ; a pair of similar teeth on the 
roof of the mouth, but the marginal upper dentition feeble. Teeth 
conical, with a very small pulp -cavity, of which the walls exhibit 

Pig. 48. 




Transverse section of Holoptychian (Dendrodont) Tooth, much magnified ; 
after Pander. 

complex infoldings, appearing closely intertwined when viewed in 
transverse section, these producing superficial vertical flutings. 
Pectoral fins acutely lobate, pelvic fins acutely or obtusely lobate ; 
two remote dorsal fins ; anal fin single ; caudal fin diphycercal or 
heterocercal. 

The typical Holoptychius is the single genus of this family as yet 
definitely determined. 

Genus HOLOPTYCHIUS, Agassiz. 

[Agassiz in Murchison's Silur. Syst. 1839, p. 599 (Holoptychus), 
and Poiss. Foss. V. G. E. 1844, p. 68.] 

Syn. Dendrodus, E. Owen, Microscopic Journal, vol. i. 1841, p. 4. 

Platyynathus, L. Agassiz, Poiss. Foss. V. G. E. 1844, pp. 61, 76. 

Lamnodus, L. Agassiz, ibid. 1845, p. 83. 

(?) Sclerolepis, E. von Eichwald, Bull. Soc. Imp. Nat. Moscou, 

vol. xvii. 1844, p. 828. 
(?) Apedodus, J. Leidy, Journ. Acad. Nat. Sci. Philad. [2] vol. iii. 

1856, p. 164. 
(As subgenus) Glyptolepis, L. Agassiz, Poiss. Foss. V. G.E. 1844, 

p. 62 (in part). 

Body short and stout, not much laterally compressed ; scales large 
and rounded, the exposed surface marked with large, longitudina 



HOLOPTYCHIIDiK. 323 

wrinkles, occasionally replaced by tubercles. Head depressed, the 
bones superficially granulated ; teeth compressed, with a pair of 
sharp edges at least in the upper portion ; anterior median jugular 
plate absent. Pelvic fins obtusely lobate, situated at or behind 
the middle of the body ; first dorsal fin opposite the pelvic pair, 
second dorsal opposite or partly posterior to the anal ; tail hetero- 
cercal, the upper lobe of the caudal fin small, the lower lobe 
triangular and obliquely truncated. 

I. Holoptychius proper. 
Holoptychius nobilissimus, Agassiz. 

1835. Gyrolepis giyanteus, L. Agassiz, Poiss. Foss. vol. ii. pt. i. p. 175, 

pi. xix. fig. 13. 
1839. Holoptychus nobilissimus, L. Agassiz, in Murchison's Silur. Syst. 

p. 600, pi. ii. bis. tigs. 1, 2 (specitic name giganteus withdrawn). 
1841. Holoptychius nobilissimus, H. Miller, Old Red Sandst. p. 162, 

pi. ix. fig. 2. 

1844. Holoptychius murchisoni, L. Agassiz, Poiss. Foss. V. G. R. p. 72, 
pi. xxii. fig. 2. [Scales.] 

1845. Holoptychius nobilissimus, L. Agassiz, ibid. pp. 73, 140, pi. xxiii., 
pi. xxiv. fig. 2, (?) pi. xxxi. a. fig. 26. 

1855. Holoptychius nobilissimus (' ? amend to noblei '), F. M'Coy, Brit. 

Palaeoz. Foss. p. 595. 
1860. Holoptychius nobilissimus, E. von Eichwald, Leth. Rossica, vol. i, 

p. 1572. 
1888. Holoptychius nobilissimus, M. Lohest, Ann. Soc. Geol. Belg. 

vol. xv. pp. 127, 139. 
1888. Holoptychius dewalquei, M. Lohest, ibid. p. 134, pi. i. fig. 5, 

pi. ii. figs. 1-4, pi. iii. figs. 1, 3, 5, 6, pi. v. figs. 1-3. [Scales; 

M. Lohest Collection, Liege.] 
1890. Holoptychius nobilissimus, Woodward & Sherborn, Cat. Brit. 

Foss. Vertebrata, p. 97. 
1890. Holoptychius nobilissimus, R. H. Traquair, Proc. Roy. Soc. 

Edinb. vol. xvii. p. 388. 

Type. Fish wanting caudal extremity, ventral aspect; British 
Museum. 

The type species, of very large size. Head and opercular 
apparatus occupying about one-fifth of the total length. Scales 
externally ornamented with numerous large branching ridges, often 
interrupted and partly tubercular on the ventral aspect of the 
abdomen, continuous and more delicate on the caudal pedicle ; the 
superficial ridges rarely alternating with, and continued by, series of 
small tuberculations at the anterior edge of the exposed area of the 
scale. 

y2 



324 CROSSOPTERYGII. 

Form. 6f Loc. Upper Old Red Sandstone : Perthshire, Fifeshire, 
and Roxburghshire. Upper Devonian : Belgium and N.W. Russia. 

P. 6258. Type specimen described and figured by Agassiz ; Clash- 
bennie, Perthshire. The fossil exhibits the ventral aspect 
and displays, in addition to the features noticed by Agassiz, 
a considerable portion of the large, acutely-lobate pectoral 
fin of the right side : the obtuse lobation of the pelvic 
pair is also very distinct. The best figure of a typical 
scale is given in Murchison's Silur. Syst. pi. ii. bis. fig. 2. 
Purchased from Rev. James Noble, about 1840. 

11531. Impression of fragments of head-bone and scales ; (?) Clash- 
bennie. Mantell Coll. 

P. 3283. Fragments of bones and scales of a large individual ; 
Clashbennie. Enniskillen Coll. 

P. 701. Fragment of bone and scales ; Clashbennie. Egerton Coll. 

47725. Associated fragments of very large scales ; Clashbennie. 

Presented by Dr. Lauder Lindsay, 1876. 

50007. Group of imperfect large scales ; Clashbennie. The 

impression of one scale shows the anterior tuberculations 
described as characteristic of H. deivalquei ; Clashbennie. 

Trevelyan Bequest. 

P. 6014. Group of very large scales, one measuring 0*07 from side 
to side, and another exhibiting the anterior tubercula- 
tions described as characteristic of H. dewalquei ; Clash- 
bennie. Purchased, 1889. 

47724. Two imperfect scales ; Maxton, Roxburghshire. 

Presented by Dr. Lauder Lindsay, 1876. 

50008. Small scale, showing anterior tuberculations ; Black Hill, 

near Melrose. Trevelyan Bequest. 

19809 a. Fragments of scales probably of this species ; " Yaldai 
Hills," Russia. Purchased, 1845. 

43452. Fragments of similar scales in similar matrix, associated 
with imperfect plates of Bothriolepis omata ; Prikscha, 
Govt, of Novgorod. 

Presented by Kenneth Murchison, Esq., 1872. 

P. 711. Slab of sandstone with numerous fragments of fishes, 
including a well-preserved scale apparently of this species ; 
Russia. Egerton Coll. 



HOLOPTYCHIID^). 



325 



Holoptychius giganteus, Agassiz. 



1839. Holoptychius, R. I. Murchison, Silur. Syst. p. 600, pi. ii. bis. 

fig. 3. 
1845. Holoptychius giganteus, L. Agassiz, Poiss. Foss. V. G. R. pp. 73, 

140, pi. xxiv. figs. 3-10. 
1848. Holoptychius princeps, F. M'Coy, Ann. Mag. Nat. Hist. [2] 

vol. ii. p. 310. [Scale ; Woodwardian Museum, Cambridge.] 

1854. Holoptychius giganteus, R. I. Murchison, Siluria, pi. xxxvi. 
fig. 11. 

1855. Holoptychius giganteus, F. M'Coy, Brit. Palaeoz. Foss. p. 594. 
1855. Holoptychius princeps, F. M'Coy, ibid. p. 595. 

1888. Holoptychius giganteus, M. Lohest, Ann. Soc. Geol. Belg. 

vol. xv. p. 146, pi. vi. figs. 2, 3, pi. vii. figs. 5, 6. 
(?)1889. Holoptychius giganteus ?, J. S. Newberry, Palaeoz. Fishes 

N. America, p. 101, pi. xix. figs. 15, 16. 
1890. Holoptychius giganteus, Woodward & Sherborn, Cat. Brit. Foss. 

Vertebrata, p. 96. 

Type. Detached scales. 

A species of very large size, known only by detached scales. 
Scales of abdominal region externally ornamented with close, thick, 
irregularly tortuous, longitudinal ridges, often branching and 
interrupted, more or less replaced posteriorly by rounded tubercles ; 
caudal scales resembling those of H. nobilissimus. 

The variety of scale named H. princeps by M'Coy is very rare, 
and may be regarded as exhibiting merely an extreme modification 
of the ornament just described. 

The teeth of this species are probably described as Dendrodus 
biporcatus (p. 338). 

Form. Sf Loc. Upper Old Red Sandstone : Elgin and Nairn. 
Upper Devonian : Belgium and N.W. Russia. (?) Catskill Group : 
Pennsylvania. 

28869. Small (? caudal) scale ; Scat Craig, near Elgin. 

Purchased, 1854. 

35992-93. About ten imperfect scales ; Scat Craig. 

Purchased, 1861. 

P. 702. Six scales ; Scat Craig. Egerton Coll. 

P. 5094. Five imperfect scales ; Scat Craig. 

Presented by John Edward Lee, Esq., 1885. 

28868. Impressions of seven scales, one small example ornamented 
as " H. princeps " and traversed by a sensory canal ; 
Alves, near Elgin. Purchased, 1854. 



326 CR0SS0PTERYG11. 

38720. Impression of medium-sized scale ; near Nairn. 

Purchased, 1804. 

P. 4732. Three imperfect scales, one being almost completely 
tuberculated, and another exhibiting only tortuous, 
branching, anastomosing ridges ; River Ssjass, Govt, of 
St. Petersburg. Purchased, 1884 



Holoptychius americanus, Leidy. 

1843. Holoptychus nobilissimus, J. Hall (non Agassiz), Geol. New 

York, pt. iv. p. 281, woodc. fig. 130, no. 2. 
1856. Holoptychius americanus, J. Leidy, Journ. Acad. Nat. Sci. Philad. 

[2] vol. iii. p. 165, pi. xvi. figs. 9, 10, pi. xvii. figs. 1-3 {non fig. 4). 
1889. Holoptychius americanus, J. S. Newberry, Palaeoz. Fishes N. 

America (Mon. U.S. Geol. Surv. no. xvi.), p. 113, pi. xix. 

figs. 12, 13. 

Type. Detached scales; Museum of the Academy of Natural 
Sciences, Philadelphia. 

A large species, known only by detached scales and fragments of 
head-bones. Scales of abdominal region externally ornamented 
with thick, irregularly tortuous, longitudinal ridges, more or less 
interrupted and branching. 

Form. <$f Loc. Catskill Group (Upper Devonian) : Pennsylvania, 
U.S.A. 

P. 5084. Three fragments of rock with imperfect scales ; Blossburg. 
Presented by John Edward Lee, Esq., 1885. 



Holoptychius halli, Newberry. 

1889. Holoptychius hallii, J. S. Newberry, Palaeoz. Fishes N. America 
(Mon. U.S. Geol. Surv. no. xvi.), p."ll4, pi. xx. fig. 10. 

Type. Imperfect trunk ; New York State Museum, Albany. 

Form and proportions of trunk as in the type species, but the fins 
apparently exhibiting a relatively greater breadth. Scales ex- 
ternally ornamented by broad, flattened, striated longitudinal ridges, 
more or less parallel, but sometimes radiating and anastomosing ; 
no tuber culations. 

Form. 6f Loc. Catskill Group (Upper Devonian) : Delhi, New 
York State. 

Not represented in the Collection. 



HOLOrTYCHIIDiE. 327 

Holoptychius flemingi, Agassiz. 

[Plate XI. figs. 1 a-cl.-] 

1844. Holoptychius femingii, L. Agassiz, Poiss. Foss. V. G. R. p. 71, 

pi. xxii. fig. 1 (non p. 140, pi. xxxi. a. fig. 25). 
1844. Holoptychius andersoni, L. Agassiz, ibid. p. 72, pi. xxii. fig. 3. 

[British Museum.] 
1844. Platygnathus jamesoni, L. Agassiz, ibid. pp. 61, 77, pi. xxv. [Tail ; 

British Museum.] 
1855. Holoptychius andersoni, F. M'Coy, Brit. Palaeoz. Foss. p. 594. 
1859. Holoptychius andersoni and H. Jiemingii, J. Anderson, Dura Den, 

p. 57, pi. i. fig. 3, pi. vii., pi. viii. figs. 1, 2. 
1859. Platygnathus jamesoni, J . Anderson, ibid. p. 56, pi. i. fig. 2. 
1863. Holoptychius Jiemingii, R. Walker, Ann. Mag. Nat. Hist. [3] 

vol. xi. p. 73, pi. ii. (lettered Glyptolepis), woodc. figs. 1-4. 
1863. Glyptolepis Jiemingii, H. Mitchell, Geologist, vol. vi. p. 43. 
1863. Glyptolepis Jiemingii, J. Powrie, Geologist, vol. vi. p. 96. 
1861. Glyptopomus, T. H. Huxley {errore), Figs, and Descrips. Brit. 

Organic Remains (Mem. Geol. Surv.), dec. x. p. 4, woodc. fig. 4. 
1866. Glyptopomus, T. H. Huxley {errore), ibid. dec. xii. pi. i. fig. 2. 
1888. Holoptychius Jiemingii, M. Lohest, Ann. Soc. Geol. Belg. vol. xv. 

p. 143, pi. iii. figs. 2, 4, pi. vi. fig. 1. 
1888. Holoptychius Jiemingii, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 513. 
1890. Holoptychius Jlemingi, Woodward & Sherborn, Cat. Brit. Foss. 

Vertebrata, p. 96. 
1890. Holoptychius Jiemingii, R. H. Traquair, Proc. Roy. Soc. Edinb. 

vol. xvii. p. 388. 

Type. Group of scales. 

A species somewhat smaller than the type. Head and opercular 
apparatus occupying nearly one-fifth of the total length ; first dorsal 
fin relatively small ; second dorsal fin partly opposed to the space 
between the anal and the caudal. Scales externally ornamented 
with well-spaced delicate antero-posterior ridges, often bifurcating 
and sometimes anastomosing anteriorly ; the ridges not interrupted, 
except rarely upon the ventral aspect of the abdominal region, but 
often continued upon the overlapped portion of the scale by short, 
delicate, radiating lines of inconspicuous tubercles. 

Form, fy Loc. Upper Old Red Sandstone : Dura Den, Fifeshire. 
Upper Devonian : Chevremont and Strud, Belgium. 

26117 b. Skull, mandible, and portion of the branchiostegal ap- 
paratus, ascribed to Glyptopomus by Huxley, loc. cit. ; 
Dura Den. The woodcut, exhibiting the upper aspect 
one-half the natural size, is reproduced in the accompany- 
ing fig. 49. Posteriorly is a broken median element 



328 



CROSSOPTERYGII. 



flanked on either side by a large bone, this series being 
sivpratemporal according to Traquair's nomenclature 
(p. 319). A pair of large parietals occurs, with a small 
squamosal on each side adjoining its hinder half; and 
the frontals are relatively small, separated by suture, and 
meeting some polygonal bones in front, but exhibiting no 
mesial foramen. The bones apparently to be regarded as 
postfrontals are larger than the frontals and squamosals, 
and are separated from the latter by the articulation of a 
large cheek-plate with the parietals. On the lower aspect 
the right mandibular ramus exhibits infradentary bones ; 

Fig. 49. 




Holoptychius jiemingi, Ag. — Dorsal aspect of head, one-half nat. size. 
[No. 261176.] 



a slender median, internal bone seems to belong to the 
hyoid apparatus; and, in addition to portions of the 
principal jugular plates, a lateral series of jugulars is well 
preserved on half of the right side. Purchased, 1851. 

37301. Imperfect head and greater portion of trunk of an equally 
large fish; Dura Den. Purchased, 1863. 



HOLOPTYCHIID^. 329 

26120 a. Portion of trunk of a somewhat smaller fish, displaying 
the scales of the ventral aspect ; Dura Den. Four of 
these scales are shown, of the natural size, in PI. XI. 
figs. 1 a-d, the first two being taken from the abdominal 
region, the third and fourth from the caudal region. The 
two latter, it will be observed, are more delicate than the 
former, and exhibit the anterior radiating rows of tubercles 
usually regarded as characteristic of ' Glyptolepis.' 

Purchased, 1851. 

26120 b. Slab with remains of about nine individuals, smaller than 
the foregoing ; Dura Den. The fins are almost entirely 
wanting, and there are only fragments of the head and 
branchiostegal apparatus ; but the scales are well pre- 
served and sometimes, in the anterior abdominal region, 
exhibit the partial subdivision of the superficial ridges. 

Purchased, 1851. 

26120 c. Group of typical scales and fragments ; Dura Den. 

Purchased, 1851. 

P. 2077-a. Imperfect fish showing portions of head and trunk, and 
a small slab with remains of about four individuals; 
Dura Den. Egerton Coll. 

P. 3277-8. Two small slabs with imperfect remains of individuals 
showing the ventral aspect, associated with fragments of 
Phaneropleuron ; Dura Den. The first specimen exhibits 
the pair of jugular plates, well preserved but accompanied 
by no anterior median plate. Enniskillen Coll. 

P. 3280-1. Two slabs, the first with remains of three individuals of 
moderate size, the second exhibiting portions of several 
small fishes with fragments of fins ; Dura Den. 

Enniskillen Coll. 

P. 3282. Imperfect fish of moderate size, exhibiting portions of the 
head, left pectoral fin, and the ventral scales ; Dura Den. 

EnnisTcillen Coll, 

26119. Type specimen of Holoptychius andersoni, Agassiz, doubtless 
to be regarded as a young individual of H. flemingi; 
Dura Den. The fossil is completely detached from the 
matrix and much crushed from above downwards. The 
dorsal aspect, figured by Agassiz, exhibits several of the 
bones of the head arranged as in No. 26117 h ; but most 
of the sutures are omitted in Dinkel's drawing. The 



330 CKOSSOPTERYGII. 

trunk affords evidence of two " lateral lines " on each side, 
the upper arising near the superior border of the oper- 
culum, and the lower near the inferior extremity of the 
clavicular plate. Purchased, 1851. 

24839. Three imperfect young individuals, laterally compressed, 
associated upon one small slab ; Dura Den. The head 
and clavicular plate are in each case preserved, but the 
extremity of the tail is wanting and all the scales and 
bones are much abraded. So far as preserved, the bones 
of the head and opercular apparatus agree with those of 
No. 2Ql\7b, and a marginal series of small conical teeth 
is seen in the jaws. One pelvic fin is shown, apparently 
displaying a trace of the lobation ; the first dorsal occurs 
directly opposite to this ; and the large second dorsal 
seems to arise somewhat behind the origin of the equally 
large anal. Purchased, 1850. 

24839 a. Several fragments of small individuals ; Dura Den. 

Purchased, 1850. 

26122. Type specimen of Platygnathus jamesoni, Agassiz, being, as 
pointed out by Traquair (loc. cit. 1888), the caudal ex- 
tremity of a species of Holoptychius, and almost certainly 
referable to H. flemingi ; Dura Den. By Agassiz the 
second dorsal fin is described as the anal, while the true 
anal and the inferior lobe of the caudal are regarded as 
two dorsals or perhaps one large dorsal accidentally 
divided. Purchased, 1851. 

(Other remains of this species are associated with Phanerojpleuron 
andersoni, and catalogued on p. 247.) 

Scales of undetermined species of Holoptychius have been recorded 
from the Old Red Sandstone of England 1 , and the following is a 
similar specimen : — 

P. 5327. Imperfect impression of small scale, in conglomerate ; 
Tortworth, Gloucestershire. 

Presented by the Earl of Ducie, 1887. 

i E. I. Murchison, Silur. Syst. (1839), pp. 175, 601 (from Crickhowell) ; 
W. H. Baily, Eep. Brit. Assoc. 1864 (1865), Trans. Sect., p. 49, and Geol. Mag. 
vol. i. (1864), p. 293. The so-called scales of Holoptychius from Devonshire 
described by J. Phillips (Palseoz. Foss. Cornwall, Devon, &c, 1841, p. 133, 
pi. lvii. figs. 256, 257) do not pertain to this genus. 



HOLOPTTCHIID^E. 331 

Other detached scales, of which there are no examples in the 
Collection, have also been named as follows : — 

Holoptychius granulatus, J. S. Newberry, Palaeoz. Pishes N. 

America (Mon. U.S. Geol. Surv. no. xvi. 1889), p. 100, 

pi. xx. fig. 9. — Chemung Group ; N. Pennsylvania. 
Holoptycliius injiexus, M. Lohest, Ann. Soc. Geol. Belg. vol. xv. 

(1888), p. 141, pi. iv. figs. 1-7, pi. v. fig. 4.— Upper 

Devonian ; Belgium. [M. Lohest Collection.] 
Holoptycliius (?) pustulosis, J. S. Newberry, op. cit. p. 100, 

pi. xx. fig. 11. — Chemung Group; Warren, Pennsylvania. 
Holoptycliius (?) radiatus, J. S. Newberry, ibid. p. 115, pi. xx. 

figs. 12-14. — Catskill Group; Pennsylvania. [American 

Mus. Nat. Hist. New York.] 
Holoptycliius tuberculatus, J. S. Newberry, ibid. p. 101, pi. xix. 

fig. 14. — Chemung Group ; Pennsylvania. 

An indeterminable dermal plate from the Devonian of Belgium is 
also named Holoptycliius omaliusi, L. Agassiz, Poiss. Foss. Y. G. E-. 
(1844), pp. 61, 75, pi. xxiv. fig. 11, and another fragment from the 
Eifel is assigned to the same species (ibid. p. 141). 

Holoptycliius falcatus and H. striatus are undefined names 
applied to Carboniferous fossils (L. Agassiz, Poiss. Foss. vol. i. 
1844, p. xxxvi). 



II. Glyptolepis. 
Holoptychius (Glyptolepis) leptopterus, Agassiz. 

[Plate XI. fig. 2.] 

1841. Glyptolepis, H. Miller (ex Agassiz), Old Eed Sandst. p. 8], pi. v. 

fig. 2. 
1844. Glyptolepis elegans, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. p. 179 

(name only). 
1844. Glyptolepis leptopterus, L. Agassiz, ibid. p. 179 (name only). 
1844. Glyptolepis leptopterus, L. Agassiz, Poiss. Foss. V. G. R. pp. 61, 

63, pis. xx., xxi., pi. xxi. a. fig. 1. 
1844. Glyptolepis elegans, L. Agassiz, ibid. pp. 61, 65, pi. xix. figs. 4, 5, 

pi. xxi. a. fig. 2. 
1848. Holoptychius sedcjwickii, F. M'Ooy, Ann. Mag. Nat. Hist. [2] 

vol. ii. p. 811. [Woodwardian Museum, Cambridge.] 
1855. Glyptolepis leptopterus, F. M'Coy, Brit. Palaeoz. Foss. p. 590. 
1855. Holoptychius sedcjwickii, F. M'Coy, ibid. p. 595, pi. ii. D. fig. 6. 



332 CROSSOPTERYGII. 

1860. Gljiptolepis leptopterus, C. H. Pander, Saurodipt., Dendrodont. 

Sec. devon. Syst. p. 62, pi. vii. tigs. 4-9. 
1888. Glyptolepis leptopterus, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 513. 

Type. Portions of fishes ; British Museum. 

The type species of Glyptolepis, attaining a maximum length of 
about OS. Head and opercular apparatus occupying somewhat 
less than one-quarter of the total length. Pectoral fins very long, 
the distal extremity, when adpressed to the trunk, reaching beyond 
the origin of the pelvic pair ; pelvic fins large, arising midway 
between the extremity of the snout and of the tail ; first dorsal fin 
relatively small ; second dorsal and anal equal in size, short and deep, 
directly opposed to each other; [caudal lobe apparently not excessively 
produced]. Scales externally ornamented with well-spaced, delicate, 
irregular antero-posterior ridges, often interrupted, sometimes 
bifurcating, and with fine scattered wrinkles in the interspaces; 
the ridges continued upon the overlapped portion of the scale by 
short, radiating lines of tubercles. 

Form. Sf Log. Lower Old Red Sandstone : Nairnshire, Banffshire, 
Cromarty, and Orkney. 1 

(i.) Lethen Bar, Nairnshire. 

P. 538, P. 3287. The first of the type specimens, being an imperfect 
head, ventral aspect, in counterpart, figured by Agassiz, 
torn. cit. pi. xx. figs. 1, 4. In addition to the pair of 
jugular plates noted by Agassiz, two of the laterals of 
the right side appear to be distinct. 

Egerton Sf Enniskillen Colls. 

P. 539. Portions of head and anterior half of abdominal region of 
trunk, figured among the type specimens by Agassiz, 
torn. cit. pi. xx. fig. 5. The tuber dilations of the head- 
bones and the ridge-ornament of the scales are only faintly 
indicated. Egerton Coll. 

P. 542, P. 3289. Imperfectly preserved abdominal region, with one 
pectoral and portions of the pelvic fins, in counterpart, 
figured among the type specimens by Agassiz, torn. cit. 
pi. xxi. fig. 2. The acutely lobate pectoral fin is identified 
with the pelvic by Agassiz, while the pelvic is named first 
anal. Egerton Sf Enniskillen Colls. 

1 An indeterminable scale from the Devonian of Eussia is also assigned to 
this species by Agassiz, Poiss. Poss. V. G. E. p. 139, pi. xxxi. a. fig. 24. 



HOLOPTYCHIIDiE. 



333 



P. 541, P. 3288. Two imperfect examples of the caudal extremity, 
figured among the type specimens by Agassiz, torn. tit. 
pi. xxi. figs. 1, 3. In the original of fig. 3, the remains 
of the pelvic fins are misinterpreted as a first anal. 

Egerton &r EnnisTcillen Colls. 

P. 3290, P. 4610. Three imperfect examples of the head and 
trunk, equalling the types in size. Enniskillen Coll. 

P. 735 a, P. 740. Imperfect similar specimen, and portion of the 
extremity of the tail. Egerton Coll, 

P. 735 b, P. 4609. Remains of head, pectoral arch, and anterior 
scales of an equally large individual. 

Egerton Sf EnnisTcillen Colls. 

20791. Yentral aspect of head and anterior abdominal region of a 
similar fish. 

Presented by Col. Sir Proby T. Cautley, K.C.B., 
$ — Gordon, Esq., 1847. 

50106. Imperfectly preserved smaller individual, wanting paired 
fins, in counterpart. Purchased, 1879. 

49179-80, 49194. Three imperfect small individuals, the first and, 
especially, the second displaying the paired fins. 

Purchased, 1878. 

(ii.) Tynet Burn, Banffshire. 

37984. Imperfectly preserved individual as large as the type speci- 
men, showing scattered bones of the head and pectoral 
arch, the left pectoral fin, and portions of the other fins. 

Purchased, 1863. 

41413. Equally large fish, broken and accidentally elongated. 

Purchased, 1869. 

P. 737-a, P. 738. Two portions of similar individuals, the first 
exhibiting a pectoral fin, the second showing the sculpture 
of the scales ; also imperfect remains of a smaller fish 
wanting the head. Egerton Coll. 

43280 a-b. Much crushed specimen of moderate size, in counter- 
part, wanting the extremity of the tail. Purchased, 1871. 

35783, P. 738 a. Nodule with remains (i.) of a similar fish, wanting 
the head, in counterpart, and (ii.) of a less complete 
individual in another plane of stratification. 

Purchased, 1860, and Egerton Coll. 






334 CROSSOPTEKYGII. 

37386. Imperfect, crushed specimen, showing some of the bones of 
the head. Purchased, 1863. 

28863. Splintered mandibular ramus, with remains of other head- 
bones. Purchased, 1854. 

(iii.) Gamrie, Banffshire. 

P. 2075. Crushed individual, distinctly showing the ornament of 
the scales. Egerton Coll, 

P. 4044. Somewhat larger specimen, in counterpart, displaying the 
pelvic and median fins, and the large club-shaped basal 
bone supporting the second dorsal. Purchased, 1883. 

P. 4043. Smaller specimen, in counterpart, showing portions of all 
the fins and the scale-ornament. Purchased, 1883. 

P. 4042. "Well-preserved small specimen, in counterpart, shown, of 
the natural size, in PI. XI. fig. 2. The head is so much 
crushed that little can be ascertained of its osteology. On 
the half not figured, the frontal bones occur, with a 
squamosal on each side, and a posterior element may be 
supratemporal ; fragments of the mandible and some of 
the cheek-plates are shown, and the imperfect operculum 
and suboperculum occur behind, while the principal jugulars 
are displaced downwards. Of the pectoral arch the gently 
curved clavicular element is conspicuous on both sides 
of the fossil. The pectoral fins are almost completely 
destroyed, but one of the pelvic pair is well preserved, 
though the obtuse lobation is indistinct ; the two dorsals 
and the anal are observed as described in the specific 
diagnosis ; and the greater portion of the lower lobe of 
the caudal fin is shown, while its upper lobe is represented 
only by a few fragmentary rays. The relatively large size 
of the scales is evident, but few exhibit the exposed sur- 
face with its sculpturing. Purchased, 1883. 

39181. Imperfect small specimen, ventral aspect. 

Purchased, 1865. 

47873. Imperfect specimen, in counterpart, 0*165 in length. 

Purchased, 1877. 

(iv.) Cromarty. 

P. 5598. Imperfectly preserved specimen, 0215 in length, showing 
portions of all the fins. Harford Coll. 



HOLOPirCHIIDiE. 335 

(v.) Eddcrton, near Tain, Ross-shire. 
P. 715. Small group of typical scales. Egerton Coll. 

(vi.) Orkney Isles. 
P. 3286. Fish with imperfectly preserved head, wanting the pectoral 
fins ; Belyacreugh. Enniskillen Coll. 

P. 3286 a. Imperfect remains of trunk and pelvic fins ; Ramna Gio. 

Enniskillen Coll. 

P. 703. Imperfect trunk and median fins ; Belyacreugh. 

Egerton Coll. 

The following specimens pertain either to large individuals of 
this species or to H. paucidens : — 

P. 537. Portion of mandible associated with large scales, described 
and figured by Agassiz, op. cit. pi. xx. figs. 2, 3 ; Lethen 
Bar. Egerton Coll. 

30875, P. 713. Large head associated with similar scales, in counter- 
part; Lethen Bar. The specimen is vertically crushed 
and much broken, thus not exhibiting the precise outlines 
of any of the elements. The infraclavicular bones of the 
pectoral arch are seen posteriorly. 

Purchased, 1855, and Egerton Coll. 

49178. Imperfectly preserved fish, about 0*5 in length, in counter- 
Fig. 50. 




Holoptychius (Glyptolepis) lepiopteriis, Ag. — Base of second dorsal fin. 
[No. 49178. 



336 CROSSOPTEETGII. 

part; Lethcn Bar. The fins are almost destroyed, but 
the supporting elements of the second dorsal are distinct, 
and are seen to consist of a single, club-shaped proximal 
bone, with about six transversely-jointed bars forming a 
distal series, as shown in the accompanying woodcut 
(fig. 50). Purchased, 1878. 

P. 736, P. 3291. Small group of scales, in counterpart, labelled 
Glyptolepis leptopterus by Agassiz ; Lethen Bar. 

Egerton Sf Ennishillen Colls. 

Holoptychius (Glyptolepis) quebecensis, Whiteaves. 

1881. Glyptolepis microlepidotus, J '. F. Whiteaves (wow Agassiz), Cana- 
dian Nat. n. s. vol. x. p. 32. 

1889. Glyptolepis quebecensis, J. F. Whiteavee, Trans. -Roy. Soc. 
Canada, vol. vi. sect. iv. p. 77, pi. v. fig. 4. 

1890. Glyptolepis quebecensis, R. H. Traquair, Geol. Mag. [3] vol. vii. 
p. 16. 

Type. Nearly complete fish ; Geological Survey Museum, Ottawa. 

A species closely related to H. {Glyptolepis) leptopterus, but not 
attaining so large a size, and differing, according to the original 
description and figure by Whiteaves, in the much smaller size of the 
pectoral fin and the greater attenuation of the caudal lobe. 

Form. <$f Loc. Upper Devonian : Scaumenac Bay, P. Q., Canada. 

Not represented in the Collection. 

Holoptychius (Glyptolepis) paucidens (Agassiz). 

1844. Flatygnathus paucidens, L. Agassiz, Poiss. Foss. V. G. R- 

pp. 61, 78, pi. xxviii. fig. 11. 
1849. " Scales, Under Jaw, Reptile Tooth, and Ischium of Aster olepis,'' 

H. Miller, Footprints of the Creator, p. 71, figs. 25, '26, 30-33, 42. 
1888. Glyptolepis paucidens, R. H. Traquair, Geol. Mag. [3] vol. v. p. 513. 
1890. Glyptolepis paucidens, R. H. Traquair, Ann. Mag. Nat. Hist. [6] 

vol. vi. p. 483. 

Type. Right mandibular ramus ; British Museum. 

A species attaining a relatively large size. Head and opercular 
apparatus occupying one-fifth of the total length. Pelvic fins 
arising considerably behind the middle point of the fish. Scales 
externally ornamented with well-spaced, delicate, irregular antero- 
posterior ridges, often interrupted, sometimes bifurcating, and with 
fine scattered wrinkles in the interspaces; the ridges continued 
upon the overlapped portion of the scale by short, radiating lines of 
tubercles. 

Form. Sf Loc. Lower Old Red Sandstone : Orkney and Caithness. 



HOLOrTYCHIID^. 



337 



P. 545. Imperfect right mandibular ramus, inner aspect, forming 
the type specimen described and figured by Agassiz, 
loc. cit. ; Orkney. Egerton Coll. 

P. 182. Imperfectly preserved head and trunk of a somewhat 
smaller individual, ventral aspect, in counterpart ; Caith- 
ness. The ornamentation of the scales is especially well 
shown. Purchased, 1881. 

P. 5934. A somewhat larger individual, ventral aspect, with 
portions of the median fins, but exhibiting only the inner 
surface of the scales ; Achanarras, Caithness. 

Purchased, 1889. 

33169. Fragment of squamation ; Thurso. Purchased, 1857. 

42401. Scale, abraded, but showing ornamentation; Castlehill, 
Caithness. Peach Coll. 

Detached scales, not represented in the Collection, are also named 
thus : — 

Glyptolepis benedeni, M. Lohest, Ann. Soc. Geol. Belg. vol. xv. 
(1888), p. 150, pi. ix. figs. 3-5, pi. x. figs. 1, 2.— Upper 
Devonian ; Belgium. [M. Lohest Collection, Liege.] 

Glyptolepis radians, M. Lohest, ibid. p. 151, pl.ix. figs. 1, 2. — 
Upper Devonian ; Belgium. [M. Lohest Collection.] 

The supposed species, named as follows, are founded upon doubtful 
fragmentary evidence : — 

Glyptolepis orbis, E. von Eichwald, Bull. Soc. Imp. Nat. Moscou, 
vol. xvii. (1844), p. 832, and Leth.Eossica, vol. i. (1860), 
p. 1568, pi. lvi. fig. 6, pi. lvii. fig. 22.— Devonian ; N.W. 
Eussia. [Fragment of jaw and scales ; University of 
St. Petersburg.] 

Glyptolepis quadrata, E. von Eichwald, ibid. (1844), p. 832, and 
ibid. (1860), p. 1569. — Devonian ; Marjina, E. Slawjanka. 
[Scales ; University of St. Petersburg.] 

Sclerolepis decorata, E. von Eichwald, ibid. (1844), p. 828, and 
vol. xix. (1846), pt. ii. p. 299, pi. x. figs. 16, 17, and 
Leth. Eossica, vol. i. (1860), p. 1570, pi. lvii. fig. 7.— Devo- 
nian ; Marjina. [Scales in University of St. Petersburg, 
assigned to Glyptolepis by C. H. Pander, Saurodipt., Den- 
drodont. &c. devon. Syst. (1860), p. 63.] 

The detached large teeth of the Dendrodont Crossopterygians 
paet n. z 



338 CR0SS0PTERYGI1. 

have been described under the generic names of Dendrodus (R. 
Owen, Microscopic Journal, vol. i. 1841, p. 4) and Lamnodus 
(L. Agassiz, Poiss. Foss. Y. G. R. 1844, pp. 61, 83). They have also 
received the following specific names : — 

Dendrodus biporcatus, Owen. 

1839. Tooth of Megalichthys or Holoptychus? , R. I. Murckison, 

Silurian System, p. 600, pi. ii. bis. figs. 8, 9. 
1841. Dendrodus biporcatus, R. Owen, Microscopic Journal, vol. i. 

p. 5, woodc. figs. 1, 2, p. 19, woodc. fig. 5. 
1841. Dendrodus compressus, R. Owen, ibid. p. 17, woodc. fig. 3. 
1841. Dendrodus biporcatus, R. Owen, Odontogr. p. 171, pi. Mi. a. 

fig. 1, pi. lxii. b. 
1841. Dendrodus hastatus, R. Owen, ibid. p. 175. 

1841. Tooth of Holoptychius, H. Miller, Old Red Sandstone, p. xxiii, 
pi. ix. fig. 4. 

1842. Dendrodus biporcatus, P. Duff, Geol. Moray, p. 67, pi. vi. fig. 5. 
1842. Dendrodus latus, P. Duff, ibid. p. 67, pi. vi. fig. 4. 

1842. Dendrodus compressus, P. Duff, ibid. p. 67, pi. vi. fig. 7. 

1844. Lamnodus pandeii, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. p. 162 

(name only). 
1844. Lamnodus biporcatus, L. Agassiz, Poiss. Foss. V. G. R. pp. 61, 

84, 144, pi. C. figs. 7-9, 14-19, pi. xxviii. figs. 6, 7, pi. xxviii. a. 

figs. 14, 15. 
1844. Lamnodus panderi, L. Agassiz, ibid. p. 61. 

1844. Dendrodus latus, L. Agassiz, ibid. pp. 61, 82, pi. xxviii. figs. 1, 2. 

1845. Lamnodus hastatus, L. Agassiz, ibid. p. 87, pi. C. figs. 1-6, 11- 
13. 

1845. Lamnodus sulcatus, L. Agassiz, ibid. p. 145, pi. xxviii. a. fig. 18. 
1860. Dendrodus biporcatus, C. H. Pander, Saurodipt, Dendrodont. 

&c. devon. Syst. p. 53, pi. x. figs. 8-13, 17, 18. 
1860. Dendrodus biporcatus, E. von Eichwald, Leth. Rossica, vol. i. 

p. 1559. 
1880. Dendrodus biporcatus, H. Trautschold, Verhandl. russ.-kais. 

mineral. Ges. St. Petersburg, [2] vol. xv. p. 139, pis. iii.-v. 
1889. Dendrodus biporcatus, J. V. Rohon, Mem. Acad. Imp. Sci. St. 

Petersbourg, [7] vol. xxxvi. no. 14, p. 28, pi. i. fig. 2. 

Type. Detached teeth. 

The type species both of Dendrodus and Lamnodus, probably 
founded upon the dentition of Holoptychius giganteus. Teeth 
robust, straight or gently curved, attaining a large size ; round or 
oval in section in the basal portion, laterally compressed above, with 
a prominent pair of opposite longitudinal keels. 

Form, fy Loc. Upper Old Red Sandstone : Elgin. Devonian : 
N.W. Russia. 



noLOPTYCniTD-io. 339 

35995. Tooth wanting base, and fragment ; Scat Craig, near Elgin. 

Purchased, 1861. 

43454 . Six imperfect abraded teeth ; Russia. 

Presented by Kenneth Murchison, Esq., 1872. 

41092. Thirty similar specimens ; Dorpat, Livonia. 

Purchased, 1868. 

P. 4489. Fragment of Holoptychian mandible showing an internal 
dentary bone with parts of the bases of two teeth ; Eiver 
Ssjass, Govt, of St. Petersburg, Russia. The ornamented 
principal dentary, with a marginal series of small teeth, is 
also seen. Purchased, 1884. 



Dendrodus strigatus, Owen. 

1841. Dendrodus strigatus, R. Owen, Microscopic Journal, vol. i. p. 17, 

woodc. fig. 1. 
1841. Dendrodus sigmoideus, R. Owen, ibid. p. 17, woodc. fig. 2. 
1841. Dendrodus strigatus, R. Owen, Odontogr. p. 175. 
1844. Dendrodus strigatus, L. Agassiz, Poiss. Foss. V. G. R. pp. 61, 

80, 143, pi. 0. figs. 10, 20-22, pi. xxviii. a. figs. 1, 2. 
(?) 1844. Dendrodus sigmoideus, L. Agassiz, ibid. pp. 61, 82, 143, 

pi. xxviii. fig. 3, pi. xxviii. a. figs. 3-5. 
(?) 1844. Dendrodus strigatus, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. 

p. 105, pi. lv. a. figs. 19, 20. 
1860. Dendrodus strigatus, C. H. Pander, Saurodipt., Dendrodont. &c, 

devon. Syst. p. 53, pi. x. figs. 15, 16. 
1860. Dendrodus sigmoides, 0. H. Pander, ibid. p. 54, pi. x. fig. 19 

(?fig.20). 

Type. Imperfect tooth. 

Teeth much elongated, often sigmoidally curved, round in section, 
with a pair of inconspicuous longitudinal keels in the upper 
portion. 

The Russian specimens commonly assigned to this " species " are 
more robust than those from the typical Scottish locality. 

Form. Sf Loc. Upper Old Red Sandstone : Scat Craig, near Elgin. 
Devonian : N.W. Russia. 

35996. Five imperfect typical teeth ; Scat Craig. Purchased, 1861. 

P. 5097. Typical tooth ; Scat Craig. 

Presented by John Edward Lee, Esq., 1885. 

43454 a. Three imperfect robust teeth ; Riga. 

Presented by Kenneth Murchison, Esq., 1872. 

z2 



3|0 CROSSOrTERYGTl. 

Other Dendrodont teeth have also been described under the 
following names : — 

Dendrodus acutatus, C. H. Pander, Saurodipt., Dendrodont. &c. 

devon. Syst. (1860), p. 55, pi. x. fig. 14.— Devonian ; 

Livonia. [Tooth, with fragment of internal dentary ; 

School of Mines, St. Petersburg.] 
Denclrodus briarti, M. Lohest, Ann, Soc. Geol. Belg. vol. xv. 

(1888), p. 118, pi. viii. fig. 3. — Upper Devonian ; Belgium. 

[M. Lohest Collection, Liege.] 
Dendrodus inflexus, E. von Eichwald, Leth. Eossica, vol. i. 

(1860), p. 1562, pi. lvii. fig. 18 : Saurichthys inflexus, 

E. von Eichwald, Bull. Soc. Imp. Nat. Moscou, vol. xix. 

(1846), pt. ii. p. 310, pi. x. figs. 35-37.— Devonian ; Marjina, 

near Pawlowsk. [University Museum, St. Petersburg.] 
(?) Dendrodus Icevis, C. G. Giebel, Abh. Naturw. Yereins fiir 

Sachsen u. Thuringen, vol. i. (1858), p. 263, pi. i. fig. 3 ; 

E. Kayser, Abh. Specialk. Preuss. u. Thiiring. Staaten, 

vol. ii. pt. 4 (1878), p. 5, pi. i. fig. 18. — Lower Devonian ; 

Harz Mountains. 
Dendrodus minor, L.Agassiz, Poiss. Foss. V. G. R. (1845), p. 144, 

pi. xxviii. a. fig. 13. — Devonian ; Megra, Russia. 
Dendrodus tenuistriatus, L. Agassiz, ibid. p. 143, pi. xxviii. a. 

figs. 6, 7 ; C. H. Pander, Saurodipt., Dendrodont. &c. 

devon. Syst. (1860), p. 54, pl.x. figs. 21,22.— Devonian; 

near St. Petersburg, and Prikscha. 
Dendrodus traqiiairi, M. Lohest, Ann. Soc. Geol. Belg. vol. xv. 

(1888), p. 117, pi. viii. figs. 2, 5 (ascribes also to this 

species, pi. xxviii. a. figs. 3-5 of Agassiz, and pi. x. fig. 20 

of Pander) . — Upper Devonian ; Belgium (? Scotland and 

N.W. Russia). [M. Lohest Collection.] 
Lamnodus minor, M. Lohest, ibid. p. 120, pi. vii. fig. 1. — Upper 

Devonian (Eamennian); Liege, Belgium. [M. Lohest 

Collection.] 
Apedodus prisons, J. Leidy, Journ. Acad. Nat. Sci. Philad. [2] 

vol. iii. (1856), p. 164, pi. xvii. figs. 5, 6.— Catskill Group ; 

North Pennsylvania. [Academy of Sciences, Phila- 
delphia.] 

Numerous Dendrodont teeth from the Devonian of Dorpat are 
assigned to the reptiles Varanus and Ichthyosaurus by S. Kutorga, 
Beitr. Geogn. u. Palaont. Dorpat's, pt. i. (1835), pt. ii. (1837) ; 
figures and descriptions are given, and five supposed new species 
of Varanus are determined. 



RHIZODONTID^E. 341 



Family RHIZODONTTDjE. 

Body fusiform, robust, elongated, and somewhat depressed, with 
cycloidal scales, more or less deeply overlapping, exhibiting a 
rounded boss or short rib on the middle of the inner side, and 
sometimes covered externally with a thin layer or detached rugae 
of ganoine. Head and opercular apparatus with well-developed 
membrane-bones ; parietals large and separate, frontals separate, 
and orbits far forwards ; interoperculum absent ; jugular plates 
comprising one large pair, flanked on either side by a lateral series, 
and with a small azygous element in front. Dentary bone of man- 
dible thin and vertical, with well-developed infradentaries in the 
same plane; an inner series of a few large, narrow, shuttle-shaped 
bones, each supporting a " laniary " tooth ; a pair of similar teeth 
on the roof of the mouth, but the marginal upper dentition feeble. 
Teeth conical, with a pulp-cavity of which the walls are vertically 
folded towards the base. Pectoral and pelvic fins obtusely lobate ; 
two remote dorsal fins, the first nearly opposite or directly opposed 
to the pelvic pair : anal fin single, caudal fin diphycercal or 
heterocercal. 



Synopsis of Genera. 

I. Infraclavicle with long upwardly directed 

process. 
Teeth smooth, with a pair of sharp edges. Rhizodus (p. 342). 
Teeth rounded in section Strepsodus (p. 348). 

II. Infraclavicle without an ascending pro- 

cess; dorsal fins directly opposed to 
pelvic and anal fins. 

Teeth rounded in section, smooth ; ring- 
vertebrae ; tail heterocercal, and cau- 
dal fin rhomboidal. Rhizodopsis (p. 354). 

No ring- vertebrae ; tail almost diphycercal, 

and caudal fin rhomboidal Gyroptychius (p. 358). 

Teeth rounded in section ; ring-vertebrae ; 

tail almost diphycercal and truncated. Tristichopterus (p. 360). 

Teeth compressed, with a pair of sharp 
edges ; ring-vertebrae ; tail hetero- 
cercal and truncated Eusthenopteron (p. 361). 



342 CROSSOPTERYGII. 

Genus RHIZODUS, Owen. 
[Odontography, 1840, p. 75.] 

Syn. Megalichthys, L. Agassiz & S. Hibbert, Trans. Roy. Soc. 
Edinb. vol. viii. 1836, p. 202 (non Megalichthys, L. Agassiz, 
1844 : see p. 378). 

The typical genus, imperfectly known, comprising species of very 
large size. Infraclavicle with a long, slender, upwardly-directed 
process. External bones and scales superficially ornamented with 
tubercles, ridges, or reticulations of ganoine. Crown of teeth 
smooth, compressed to a sharp edge anteriorly and posteriorly. 
No ossified vertebrae. 

So far as known, the genus Rhizodus is confined to the Lower 
Carboniferous, and its remains are very fragmentary. Of the fins, 
only the lobate pectoral has been discovered l . 

Rhizodus hibberti (Agassiz & Hibbert). 

[Plate XII. figs. 1-4.] 

1793. " Fishes' Teeth," D. Ure, Hist. Rutherglen & Kilbride, p. 330, 
pi. xix. figs. 4, 6. 

1836. Megalichthys hibberti, Agassiz & Hibbert, Trans. Roy. Soc. 
Edinb. vol. xiii. p. 202, pi. viii. fig. 1 {non fig. 2), pi. ix. figs. 2, 3, 
9, 10 ; woodc. on p. 183. 

1837. Megalichthys hibberti, W. Buckland, Geol. & Mineral, ed. 2 
vol. ii. p. 43, pi. xxvii. fig. 12. 

1837. Holoptychus hibberti, W. Buckland, ibid. p. 43, pi. xxvii. figs. 

9-11, 13, 14. 
1841. Rhizodus hibbertii, R. Owen, Odontogr. vol. i. p. 75, vol. ii. p. 12, 

pi. xxxv. fig. 2, pis. xxxvi., xxxvii. 
1844. Holoptychius hibberti, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. p. 180 

(name only). 
(?) 1843. Phyllolepis tenuissimus, L. Agassiz, ibid. p. 180 (name only). 
1855. Rhizodus hibbeHi, F. M'Coy, Brit. Pakeoz. Foss. p. 612. 
1855. Rhizodus gracilis, F. M'Coy, ibid. p. 611, pi. iii. g. rig. 17. 

[Dentary ; Woodwardian Museum, Cambridge.] 

1865. Rhizodus hibberti, J. Young, Trans. Geol. Soc. Glasgow, vol. ii. 
p. 38. 

1866. Rhizodus, J. Young, Quart. Journ. Geol. Soc. vol. xxii. p. 599 
(except scales). 

1876. Rhizodus, W. J. Barkas, Monthly Review Dental Surgery, vol. iv. 
p. 394, figs, lxxx., lxxxi. 

1 R. H. Traquair, Ann. Mag Nat. Hist. [4] vol. xv. 1875, p. 267. 



BHTZODONTIDJE. 343 

1877. Mhizodus hibberti, R. H. Traquair, Ann. Mag. Nat. Hist. [4] 
vol. xix. p. 303, and Proc. Roy. Soe. Edinb. vol. ix. p. 058. 

(?) 1881. Rhizodus, T. Stock, GeoL Mag. [2] vol. viii. p. 77, and Trans. 
Edinb. Geol. Soc. vol. iv. p. 38. 

Type. Portions of jaws with teeth ; olim Hibbert Collection. 

The type species, of very large size. Head and opercular bones 
superficially tuberculated ; exposed area of scales also ornamented 
with fine granules, confluent into short wavy ridges towards the 
hinder margin ; clavicle and infraclavicle superficially ornamented 
with delicate reticulating ridges and pits. 

Form. Af Loc. Calciferous Sandstones and Carboniferous Lime- 
stone Series : South Scotland. Redesdale Ironstone : Northumber- 
land. 

Unless otherwise stated, the following specimens were obtained 
from the Blackband Ironstone (Lower Carboniferous Limestone) of 
Gilmerton, near Edinburgh : — 

24337. Imperfect mandible associated with remains of jugular 
plates, the right clavicle, and some stout fin-rays. Two 
of the infradentary bones are distinct on the right side. 

Purchased, 1849. 

21222 a. Fragment of head showing three imperfect large mandi- 
bular teeth, doubtfully of this species. Purchased, 1847. 

21222 b. Portions of mandible and jugular plates. 

Purchased, 1847. 

20707. Plaster cast of portions of mandible, figured by Owen, 
loc. cit. Purchased. 

21975 a. Portion of right dentary, with the anterior large tooth. 

Purchased, 1848. 

39462. Imperfect right mandibular ramus. Bowerbanlc Coll. 

21222 C. Left mandibular ramus, displaying three of the large teeth. 

Purchased, 1847. 

40327. Anterior portion of right dentary with teeth. 

Purchased, 1867. 

47716. Imperfect left mandibular ramus, inner aspect, and other 
remains. Presented by Dr. Lauder Lindsay, 1876. 

21222 d. Portions of mandible, the right dentary showing two 
very large anterior teeth in close apposition. 

Purchased, 1847. 



344 CROSSOPTERYGII. 

P. 718-20, P. 2071. Three portions of left mandibular rami, and 
a slab with remains of both rami of a mandible. 

Egerton Coll. 

P. 3316-18. Three specimens showing portions of mandible, the 
second being a left ramus displaying the infradentaries, 
and shown of one-third the natural size in PI. XII. fig. 1. 

Enniskillen Coll. 

41111. Base of a very large mandibular tooth, with the supporting 
bone. Bryson Coll. 

P. 3315. Tooth about 0*17 in length, wanting the apex, and fixed 
to the supporting bone. Enniskillen Coll. 

24846-48. Three large mandibular teeth. Purchased, 1850. 

40150. Crushed large mandibular tooth ; Blackband (Carboniferous 
Limestone), Jordan Hill. 

Presented by Archibald Smith, Esq., 1866. 

41109-10, 41112-14. Five large mandibular teeth. Bryson Coll 

50010. Large mandibular tooth. Trevelyan Bequest. 

P. 717. Three large mandibular teeth; Carboniferous Limestone, 
LochgeHy, Fife. Egerton Coll. 

P. 3319. Three large mandibular teeth ; LochgeHy. 

Enniskillen Coll. 

P. 5123. Tooth 0-14 in length. Purchased, 1886. 

P. 717 a. Two imperfect large mandibular teeth ; Calciferous Sand- 
stone, Burdiehouse. Egerton Coll. 

P. 4800. Four mandibular teeth, doubtfully of this species ; Fossil 
Blackband (Middle Carboniferous Limestone), Airdrie, 
Lanarkshire. One specimen, showing facettes, is repre- 
sented, of the natural size, in PL XII. fig. 2. 

Armstrong Coll., transferred from Mus. Science <$f 
Art, Edinburgh, 1884. 

21975 b. Operculum, inner aspect ; Burdiehouse. Purchased, 1848. 

21222 e. Obscure remains of pectoral arch, with a few robust, 
unarticulated fin-rays. Purchased, 1847. 

47717. Left clavicle broken across the middle and the upper 
portion somewhat displaced downwards. The exposed 
area is covered with the characteristic fine reticulations ; 
the anterior concave border is thickened, somewhat bent 



RHIZODONTTDJE. 345 

inwards, and bounded by a broad smooth space ; the 
posterior border of the inferior expanded half is thin, and 
immediately behind and within this border in the upper 
half there extends an inwardly and backwardly directed 
plate expanding upwards. 

Presented by Dr. Lauder Lindsay, 1876. 

21222 f. Eight clavicle, inner aspect, about 0-32 in maximum 
length, shown of one-third the natural size in Plate XII. 
fig. 3. The inferior half forms a broad triangular expan- 
sion, laterally compressed, and the superior extremity, 
though relatively thicker and smaller, is somewhat 
expanded in the same plane ; midway the bone is antero- 
posteriorly compressed, thus having a twisted appearance, 
and the inflexion of the anterior border of the expanded 
areas gradually diminishes above and below from this 
point. The postero-superior inner plate noted in No. 47717 
forms part of the upper expansion when viewed from the 
aspect shown in the specimen now figured, and here it is 
somewhat broken and distorted by pressure. 

Purchased, 1847. 

30533. Much crushed and broken left clavicle. Purchased, 1856. 

24841. Eight infraclavicle, inner aspect, exhibiting the elongated, 
rod-like, postero-superiorly directed process from the 
middle of its upper border. The bone is shown, of one- 
third the natural size, in PI. XII. fig. 4, and is associated 
with portions of the right mandibular ramus. 

Purchased, 1850. 

35728. More imperfect example of the left infraclavicle, showing 
the characteristic external ornament of fine reticulations. 

Purchased, 1859. 

47726. Imperfect remains of infraclavicles associated with frag- 
ments of mandible. Purchased, 1876. 

P. 721. Three imperfect scales ; Burdiehouse. Egerton Coll. 

P. 3323. Three imperfect scales ; Burdiehouse. Enniskillen Coll. 

An imperfect dentary bone from the St. Louis Limestone (Lower 
Carboniferous) of Alton, Illinois, U.S.A., in the Museum of 
Columbia College, New York, closely resembles the corresponding 
element of B. hibberti. The laniary teeth, however, seem to be 
more compressed, with sharper edges, and the specimen is thus 



346 CTtOSSOPTERYGTI. 

regarded as the type of a distinct species, Rhizodus anceps, J. S. 
Newberry, Trans. New York Acad. Sci. vol. vii. (1888), p. 165, 
and Paloeoz. Pishes N. America (Mon. U. S. Geol. Surv. no. xvi. 
1889), p. 191, pi. xliii. fig. 1. 

An imperfect Rhizodont laniary tooth, perhaps of the same 
species, from the same formation and locality, is theoretically 
associated by Newberry with a fossil which appears to the present 
writer to be the superficially calcified meckelian cartilage of an 
Elasmobranch. These two specimens (in the Museum of Columbia 
College) form the basis of a supposed genus Ccelosteus, J. S. New- 
berry (Trans. New York Acad. Sci. vol. vi. 1887, p. 137), with the 
single species, C.ferox (ibid., and Palaeoz. Pishes N. America, 1889, 
p. 190, pi. xxxv. figs. 1-4). 



Rhizodus ornatus, Traquair. 
[Plate XII. figs. 5-9.] 

1836. Megalichthys hibberti, Agassiz & Hibbert (errore), Trans. Roy. 

Soc. Edinb. vol. xiii. pi. viii. fig. 2 (scale). 
1866. Rhizodus, J. Young, Quart. Journ. Geol. Soc. vol. xxii. p. 599 

(scales only). 
1875. Rhizodus hibberti, R. H. Traquair (non Ag. & Hibb.), Ann. Mag. 

Nat. Hist. [4] vol. xv. p. 266. 
1875. Rhizodus, L. C. Miall, Quart. Journ. Geol. Soc. vol. xxxi. p. 624, 

woodc. (inferior aspect of head, showing jugular plates). 
1877. Rhizodus ornatus, R. H. Traquair, Proc, Roy. Soc. Edinb. vol.ix. 

p. 659. 

Type. Anterior portion of fish ; Edinburgh Museum. 

A species much smaller than R. hibberti. Head, opercular 
and clavicular bones, and also scales, externally ornamented with 
very coarse tuberculations, usually confluent into nodose, often 
reticulating ridges. Clavicle and infraclavicle relatively narrower 
antero-posteriorly than in R. hibberti, and the scales thicker. 

Form. $• Log. Calciferous Sandstones and Lower Carboniferous 
Limestone Series : South Scotland. 

Unless otherwise stated, the following specimens were obtained 
from the Blackband Ironstone (Lower Carboniferous Limestone) of 
Gilmerton, near Edinburgh : — 

P. 3345. Head and anterior portion of trunk, viewed from the ventral 
aspect. The mandible and portions of the jugular plates 
and operculum exhibit the superficial ornamentation of 
blunt tubercles and large, nodose, reticulating ridges ; while 



RHTZODONTIDiE. 



347 



the clavicle of each side is marked externally with fainter, 
though almost equally coarse, reticulations. The last- 
named bone in each case is imperfect superiorly, but the 
lower expanded portion (PI. XII. fig. 6) is relatively 
longer and narrower than the corresponding part of the 
clavicle in E. hibberti (PL XII. fig. 3). No traces of the 
pectoral fins are preserved, and most of the scales are 
seen only from the inner side. Some scale-fragments 
(PL XII. fig. 8), however, show that "the exposed area 
of the external surface is marked with short, interrupted, 
wavy, reticulating ridges, whose direction is mainly 
parallel with the posterior border of the scale ; while in 
the interval between these, more delicate ridges are seen 
radiating from the centre " (Traquair). EnnisTcillen Coll. 

P. 363. Portion of dentary with teeth, associated with imperfect 
scales. Purchased, 1881. 

P. 3320. Portion of dentary with teeth ; Burdiehouse. 

EnnisTcillen Coll. 

P. 3321. Left principal jugular plate and operculum, associated with 
the infraclavicle of the right side. The operculum, with 
its characteristic ornamentation, is shown, of the natural 
size, in PL XII. fig. 5, and the infraclavicle, from the 
inner aspect, in fig. 7. As remarked by Traquair, the 
last-named bone has a relatively less antero-posterior 
measurement than the corresponding element in R. hibberti. 

EnnisTcillen Coll. 

P. 332 2-a. Operculum associated with left infraclavicle and other 
fragments ; also two imperfect detached opercula. 

EnnisTcillen Coll. 

36911-12. Operculum and (?) suboperculum. Purchased, 1863. 

47718. One of the principal jugular plates, in counterpart ; Calcife- 
rous Sandstone, Burdiehouse, near Edinburgh. 

Presented by Dr. Lauder Lindsay, 1876. 

21223, 21421. Two small scales, inner aspect. Purchased, 1847. 

21975. Group of scales. Purchased, 1848. 

41125. Small scale, inner aspect. Bryson Coll. 

15533. Small scale, inner aspect ; Burdiehouse. Purchased. 

21223 a. Group of scales ; Burdiehouse. Purchased, 1847 '. 



348 CROSSOPTETtYGTJ. 

35663. Group of scales ; Burdiehouse. Bean Coll. 

36914. Scale, inner aspect, shown, of the natural size, in PI. XII. 
fig. 9 ; Burdiehouse. Purchased, 1863. 

P. 721. Three detached scales, and small group of three, all inner 
aspect ; Burdiehouse. Egerton Coll. 

P. 3323. Group of scales, inner aspect; Burdiehouse. 

Ennislcillen Coll. 

The teeth and portions of jaws in the Museum of Columbia 
College, New York, described under the following names, are 
probably all Labyrinthodont : — 

Bhizodus angustus, J. S. Newberry, Proc. Acad. Nat. Sci. Philad. 
vol. viii. (1856), p. 99, and Bep. Geol. Surv. Ohio, vol. i. 
pt. ii. (1873), p. 342, pi. xxxix. fig. 6. — Coal-Measures ; 
Linton, Ohio. 

Bhizodus incurvus, J. S. Newberry, ibid. 1856, p. 99. — Coal- 
Measures ; Linton, Ohio. 

Bhizodus lancifer, J. S. Newberry, ibid. 1856, p. 99, and ibid. 
1873, p. 342, pi. xxxix. fig. 9. — Coal-Measures ; Linton, 
Ohio. [Very similar teeth from the Coal-Measures of 
Northumberland are also noticed (under the name of JR. 
lanceiformis) by Hancock and Atthey, Ann. Mag. Nat. Hist. 
[4] vol. i. (1868), p. 271. These are determined to 
be Pteroplaoc both by the last-mentioned authors and by 
J. Young, Bep. Brit. Assoc. 1869, Trans. Sect. p. 101.] 

Mioganodus laniarius, R. Owen (Trans. Odontol. Soc. vol. v. 
1867, p. 357, pi. viii.), from the Coal-Measures of Northumberland, 
also sometimes referred to Bhizodus, is founded upon a micro- 
scopical section of a tooth, probably of the Labyrinthodont Loocomma. 
The type specimen is in the Collection. (P. 6244. Presented by 
Sir Bichard Owen, K.C.B., 1890.) 

A scale of uncertain genus, but probably of Strepsodus, from the 
Coal-Measures of Hlinois, is named Bhizodus occidentalis, Newberry 
& Worthen, Pal. Illinois, vol. ii. (1866), p. 19, woodc. fig. 2. 



Genus STREPSODUS, Young. 
[Quart. Journ. Geol. Soc. vol. xxii. 1866, p. 602. J 

Syn. Dendroptychius, J. Young {ex Huxley, MS.), Quart. Journ. Geol. 
Soc. vol. xxii. 1866, p. 601. 



RFIIZOnONTTD.T;. 



349 



Archichthys, A. Hancock & T. Atthey, Aim. Mag. Nat. Hist. 

[4] vol. v. 1870, p. 268. 
Labyrinthodontosaurus, T. P. Barkas, Coal-Meas. Palaeont. 1873, 

p. 75. 

An imperfectly known genus, comprising species of medium or 
large size. Teeth subulate, without longitudinal keel, more or less 
bent inwards, and often sigmoidally curved ; outer face nearly or quite 
smooth, inner face with vertical striations. Vertebral centra in the 
form of thin discs, pierced by a large mesial foramen for the passage 
of the remnant of the notochord. Scales very thin and deeply imbri- 
cating ; inner surface with a median, antero-posteriorly elongated 
protuberance, and a hinder sector marked by small pits ; exposed 
surface relatively small, ornamented with few, large, longitudinal 
furrows, somewhat radiating and occasionally branching. 

The clavicle and infraclavicle of this genus are identical in form 
with those of Bhizodus described above (pp. 345, PL XII. figs. 3-6). 



Strepsodus sauroides (liinney). 
[Plate XVI. figs. 1, 2.] 

1841. Holoptychius sauroides, E. W. Binney, Trans. Manchester Geol. 

Soc. vol. i. p. 165, pi. v. fig. 7.] 
1844. Holoptychius sauroides, L. Agassiz, Poiss. Foss . vol. ii. pt. ii. 

p. 180 (name only). 
1844. Holoptychius yarneri, L. Agassiz, ibid. p. 180 (name only). 
1864. Holoptychius sauroides, Kirkby & Atthey, Trans. Tyneside Nat. 

Field Club, vol. vi. p. 234, pi. vi. figs. 5, 6. 
1866. Strepsodus, J. Young (ex Huxley, MS.), Quart. Journ. Geol. Soc. 

vol. xxii. p. 602, woodc. fig. 3. 
1866. Dendroptychius,J. Young (ex Huxley, MS.), ibid. p. 601, woodc. 

fig. 7. [Scale ; Museum of Practical Geology.] 
1869. Strepsodus, T. P. Barkas, Scientific Opinion, vol. i. p. 556. 

1872. Strepsodus sauroides, G. Lyon, Trans. Edinb. Geol. Soc. vol. ii. 
p. 125. 

1873. Labyrinthodontosaurus simmi, T. P. Barkas, Coal-Meas. Palaeont. 
pp. 75, 94, figs. 194, 223, 224. [Fragment of mandible ; T. P. 
Barkas Collection, Newcastle-upon-Tyne.] 

1873. Strepsodus, T. P. Barkas, ibid. p. 32, figs. 113-119. 

1875. Strepsodus sauroides, J. Ward, [Proc] N. Staffs. Nat. Field Club, 

p. 232. 
1875. Rhizodus (Holoptychius) yarneri, J. Ward, ibid. p. 233, fig. 4. 

[Scale ; J. Ward Collection, Longton.] 

1875. Dendroptychius, J. Ward, ibid. p. 233. 

1876. Strepsodus, W. J. Barkas, Monthly Rev. Dental Surgery, vol. iv. 
pp. 481, 529, figs, lxxxvi.-lxxxviii. 



350 CROSSOPTERYGT I . 

1890. Strepsodus saiiroides, Woodward & Sherborn, Cat. Brit. Foss. 

Vertebrata, p. 189. 
1890. Strepsodus saiiroides, J. Ward, Trans. N. Staffs. Inst. Mining 

Engin. vol. x. p. 160, pi. ii. tigs. 5, 25. 

Type. Tooth ; E. W. Binney CoUection. 

The type species. Teeth relatively 1 ong and slender, somewhat 
laterally compressed, often sigrnoidally bent at the apex ; inner face 
covered with prominent, thread-like, well-spaced striae almost to the 
apex ; basal folds very short. Jaw externally ornamented with fine 
tuberculations. 

Form, fy Log. Coal-Measures : English, Scottish, and Irish Coal- 
fields. 

P. 364. Three slabs of shale showing fragments of jaws and other 
head-bones associated with vertebrae and scales ; Black- 
band, Airdrie, Lanarkshire. Purchased, 1881. 

37323, 41999. Two fragments of mandible with imperfect teeth j 
Airdrie. Purchased, 1863, 1870. 

P. 2287. Associated fragments of jaws; Carluke. 

Presented by George Griffiths, Esq., 1882. 

Kg. 51. 




Strepsodus sauroides (Binney). — Tooth, natural size. Coal-Measures, England. 

49119. Fragments of mandible showing one of the large teeth, and 
traces either of tubercular ornament, or a rugose surface 
left by the removal of superficial ganoine ; Scotland. 

Purchased, 1878. 

21227, 21423. Twelve teeth, and small group of tooth-fragments ; 
Carluke. Purchased, 1847. 

37957. Large robust tooth ; Airdrie. Purchased, 1863. 



RHIZODONTID^. 351 

42000. Similar tooth, wanting the apex, but showing the basal 
folds ; Airdrie. Purchased, 1870. 

P. 4805. Small tooth ; Palace Craig Ironstone, Carnbroe, Lanark- 
shire. Armstrong Coll., transferred from Mus. Science 

and Art, Edinburgh, 1884. 

P. 6282. Imperfect small tooth ; Low Main Seam, Newsham. 
Newcastle-upon-Tyne. History unknown, 

P. 782. Large slender tooth with traces of basal folds ; Lower Coal- 
Measures, Lowmoor, Yorkshire. Egerton Coll. 

P. 1186. Three teeth; Middle Coal-Measures, Tingley, Yorkshire. 

Egerton Coll. 

P. 3271. Three teeth ; near Leeds. Enniskillen Coll. 

P. 3270. Six teeth ; Longton, Staffordshire. Enniskillen Coll. 

P. 4090. Tooth ; Old Hill, near Stourbridge. 

Presented by Horace Pearce, Esq., 1883. 

P. 5239. Crushed tooth ; near Dudley. Purchased, 1886. 

41634. Imperfect vertebra ; Newsham, Newcastle-upon-Tyne. 

Presented by T. P. Barkas, Esq., 1869. 

41851 x. Imperfect vertebrae and associated fin-rays ; Jarrow Col- 
liery, Kilkenny, Ireland. Purchased, 1870. 

38558-59. Two scales ; Airdrie. Purchased, 1864. 

P. 4579. Scale ; Carluke. Enniskillen Coll. 

19809, 19943. Pour scales ; Newsham, Newcastle-upon-Tyne. 

Purchased, 1845, 1846. 

36478. Group of scales, the inner aspect of one shown, of two-thirds 
nat. size, in PL XVI. fig. 2 ; Longton. Purchased, 1862. 

P. 4578. Scale ; Longton. Enniskillen Coll. 

40533. Scale showing impression of external furrows, represented 
of two-thirds nat. size in PI. XVI. fig. 1 ; locality unknown. 

Purchased, 1867. 

P. 4577. Scale labelled " Megalichthys hibberti" in Agassiz's hand- 
writing j Jarrow Colliery, Kilkenny, Ireland. 

Enniskillen Coll. 



352 CROSSOPTTIRYOm. 

Strepsodus striatulus, Traquair. 

1882. Strepsodus striatulus, R. H. Traquair, Geol. Mag 1 . [2] vol.ix. p. 544. 
1890. Strepsodus striatulus, R. H. Traquair, Proc. Hoy. Soc. Edinb. 
vol. xvii. p. 389. 

Type. Teeth ; collection of Dr. R. H. Traquair. 

Teeth not attaining so large a size as those of the typical species ; 
never with a sharply-bent apex, and distinguished by the extreme 
fineness of the inner striae, which are closely arranged. 

Form. 6f Loc. Middle Carboniferous Limestone (Edge-Coal Series) : 
Borough Lee, near Edinburgh, and Abden, Fife. 

P. 4497. Two teeth. Presented by Dr. B. H. Traquair, 1884. 

Strepsodus sulcidens (Hancock & Atthey). 

1868. Rhizodus hibberti, Hancock & Atthey (errore), Ann. Mag. 

Nat. Hist. [4] vol. i. p. 346; also Nat. Hist. Trans. Northumb. and 

Durham, vol. iii. p. 81. 
1870-71. Archichthys sulcidens, Hancock & Atthey, Ann, Mag. Nat. 

Hist. [4] vol. v. p. 268, and vol. vii. p. 79. 

1872. Archichthys sulcidens, Hancock & Atthey, Nat. Hist. Trans. 
Northumb. & -Durham, vol. iv. pp. 201, 393. 

1873. Archichthys, T. P. Barkas, Coal-Meas. Pala3ont. p. 38, figs. 141, 
142. 

1876. Archichthys sulcidens, W. J. Barkas, Monthly Rev. Dental Sur- 
gery, vol. v. p. 7, figs, xci.-xciv. 

1890. Archichthys sulcidens, R, H. Traquair, Proc. Roy. Soc. Edinb. 
vol. xvii. p. 389. 

Type. Mandibular ramus ; Newcastle-upon-Tyne Museum. 

The type species of " Archichthys" attaining a relatively large 
size. Teeth robust, but elongated, somewhat laterally compressed, 
with a straight apex : strise npon inner face very fine ; broad, faint, 
vertically-elongated depressions extending upwards for a short space 
above the basal furrows. 

Form. Sf Loc. Coal-Measures : Midlothian, Northumberland, and 
Staffordshire. 

41116. Imperfect tooth ; Dalkeith, near Edinburgh. 

Purchased, 1868. 

45865 C. Tooth ; Low Main Seam, Newsham, near Newcastle-upon- 
Tyne. Purchased, 1874. 

P. 723-4. Two teeth : Newsham. Egerton Coll. 

P. 3268. Tooth ; Newsham. EnnisHUen Coll. 



RHTZODONTID^. 353 

P. 5136. Two teeth; Newsham. 

Presented by William Dinning^ Esq., 1886. 

P. 785, P. 792. Two teeth; Longton, Staffordshire. Egerton Coll. 

P. 3269. Tooth ; Longton. Enniskillen Coll. 

Strepsodus portlocki (Portlock). 

1843. Holopty chins portlockii, J. E. Portlock (ex Agassiz, MS.), Rep. 
Geol. Londond. p. 464, pi. xiii. figs. 1-9. 

1844. Holoptychius portlockii, L. Agassiz, Poiss. Foss. vol. i. p. xxxvi 
(name only). 

1855. Rhizodus hibberti?, F. M'Coy, Brit. Palajoz. Foss. p. 613. 
1878. Archichthys portlockii, R. H. Traquair, Proc. Roy. Soc. Edinb. 

vol. ix, p. 657. 
1881. Archichthys portlockii, R. H. Traquair, Trans. Roy. Soc. Edinb. 

vol. xxx. p. 18. 
1888. Rhizodus portlockii, R. Etheridge, Foss. Brit. Islands, pt. i. p. 341. 
1890. Archichthys portlocki, R. H. Traquair, Proc. Roy. Soc. Edinb. 

vol. xvii. p. 389. 

Type. Teeth and scales ; Museum of Practical Geology. 

Teeth closely similar to those of S. sulcidens, but apparently shorter 
and broader and without vertically-elongated depressions above the 
basal furrowed portion. 

Form. Sf Loc. Lower Carboniferous : Derry, Tyrone, Fermanagh, 
and Antrim, IS". Ireland. Calciferous Sandstones : Liddesdale, 
Dumfriesshire ; Pittenween and Abden, Fifeshire. 

P. 725. Imperfect small scales ; Maghera, Co. Derry. 

Egerton Coll. 

P. 4580. Remains of larger scales ; Maghera. Enniskillen Coll. 

P. 4596. Group of similar scales ; Ballynascreen, Derry. 

Enniskillen Coll. 



Strepsodus hardingi (Dawson). 

1868. Rhizodus hardingi, J. W. Dawson, Acadian Geology, ed. 2, 

p. 254, fig. 77 a-d. 
1890. Strepsodus, A. S. Woodward, Geol. Mag. [3] vol. vii. p. 457. 

Type. Fragment of mandible and tooth ; Peter Redpath Museum, 
Montreal. 

Teeth much laterally compressed, sometimes facetted, slightly 
curved, with slender apex ; fine striations distally on the concave 
side, but extending round the plicated basal portion. 

PART II. 2 A 



354 CROSSOPTERYGII. 

Form, cj- Log. Lower Carboniferous : Horton Bluff, Nova Scotia. 
Not represented in the Collection. 

An undetermined small species, with teeth resembling those of 
S. sauroides (Traquair, Trans. Roy. Soc. Edinb. vol. xxx. p. 1 8) is 
indicated by the following specimens : — 

P. 4054. Two teeth, 0*01 in length, incurved at the apex ; Calci- 
ferous Sandstones (Cement-stone Group), Eskdale, Dum- 
friesshire. Purchased, 188,3. 

P. 4054 a. Oval scale, 0'038 in long diameter ; Eskdale. 

Purchased, 1883. 

Scales, with associated teeth, from the Caleiferous Sandstones of 
Pitcorthy, Pife, are also named Strepsodus minor, R. H. Traquair, 
Proc. Roy. Soc. Edinb. vol. xvii. (1890), p. 393. [Edinburgh 
Museum.] 

Other scales much resembling those of Strepsodus have been 
described from the Upper Devonian of Mimers Dal, Spitzbergen, by 
E. R. Lankester, Handl. k. Svenska Yetensk. Akad. vol. xx. no. 9 
(1884), p. 5, figs. 7-12. [State Museum, Stockholm.] Compare also 
Sauripterus (p. 364). 

A fragmentary scale from the Chatham Series of North Carolina, 
figured under the name of Rabdiolepis speciosus by E. Emmons 
(Manual Geol. ed. 2, 1860, p. 183, fig. 161), also exhibits some 
resemblance to Strepsodus. 

Genus RHIZODOPSIS, Young. 
[Quart. Journ. Geol. Soc. vol. xxii. 1866, p. 596 l .] 

Syn. Dittodus, R. Owen, Trans. Odontol. Soc. vol. v. 1867, p. 325 (in 
part). 
Ganolodus, R. Owen, ibid. p. 354 (in part). 
Characodus, R. Owen, ibid. p. 366. 
Gastrodus, R. Owen, ibid. p. 370. 
Orthognathus, T. P. Barkas, Coal-Meas. Palaeont. 1873, p. 38. 

Body much depressed anteriorly, with narrow ovoid scales, of 
which the exposed portion is covered with a thin film of ganoine, 
while the inner face is marked by a median boss and punctations 
posteriorly. Teeth round in section, smooth. Vertebras ring-shaped. 
First dorsal fin opposed to the pelvic pair, and the second dorsal to 
the anal ; tail heterocercal, the caudal fin rhomboidal in form. 

1 This definition is said to be based upon the unpublished observations of 
Huxley. The generic name is incidentally mentioned by Huxley, Mem. Geol. 
Surv. dec. xii. (1866), p. 31, footnote. 



khizodontid^:. 355 

The superficial film of ganoine upon the scales and external bones 
of this genus being very thin, it is usually destroyed. The scales, 
as a rule, exhibit a few concentric markings crossed by numerous 
very fine, radiating lines, due to the inner structural features. 

The osteology of the head and branchiostegal apparatus has been 
described in detail by Traquair l , who gives the restorations already 
described on p. 319 (fig. 47). 

Rhizodopsis sauroides (Williamson). 

1837. " Fossil Salmon," W. C. Williamson, Phil. Mag. [3] vol. xi. p. 300, 

pi. ii. figs. 4-6. [Scales.] 
1841. Holoptychius, sp. nov., E. W. Binney, Trans. Manchester Geol. 

Soc. vol. i. p. 165, pi. v. fig. 6. [Dentary bones ; E. W. Binney 

Collection.] 
1841. Holoptychius sauroides, E. W. Binney (errore), ibid. p. 165, pi. v. 

figs. 8, 10. [Scales.] 
1844. Holoptychius granidatus, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. 

p. 180 (name only). 
1849. Holoptychius sauroides, W. C. Williamson, Phil. Trans, p. 457, 

pi. xlii. figs. 21-23. 
1861. JRhizodus granulatus, J. W. Salter, Foss. S. Welsh Coalfield 

(Mem. Geol. Surv. — Iron Ores Gt. Britain, pt. iii.), p. 223, pi. i. 

figs. 4-6 (also teeth, ibid. pi. i. figs. 1-3, 7-9). 
1864. Holoptychius, sp. indet, Kirkby & Atthey, Trans. Tyneside Nat. 

Field Club, vol. vi. p. 235, pi. vi. fig. 4. 

1866. Rhizodopsis sauroides, J. Y oung, Quart. Jo urn. Geol. Soc. vol. xxii. 
p. 596, woodc. fig. 8. 

1867. Dittodus parallelus, R. Owen, Trans. Odontol. Soc. vol. v. p. 325 
pi. i. [Micro, section of jaw; British Museum.] 

1867. Ganolodus cragyesii, R. Owen, ibid. p. 356, woodcut. [Dentary 

bone ; British Museum.] 
1867. Characodus confertus, R. Owen, ibid. p. 366, pi. xiii. [Micro. 

section of tooth.] 

1867. Gastrodus propositus, R. Owen, ibid. p. 370, pis. xiv., xv. [Micro. 
section of jaw j British Museum.] 

1868. Rhizodopsis sauroides, Hancock & Atthey, Ann. Mag. Nat. Hist. 
[4] vol. i. p. 349. 

1870. Rhizodopsis sauroides, Hancock & Atthey, Nat. Hist. Trans. 

Northumb. & Durham, vol. iii. pp. 85, 91. 
1873. Orthognathus reticulosus, T. P. Barkas, Coal-Meas. Palaaont. 

p. 38, figs. 143, 144. [Portions of jaws; T. P. Barkas Collection.] 
1873. Rhizodopsis, T. P. Barkas, ibid. p. 23, figs. 59-69. 
1875. Rhizodopsis sauroides, J. Ward, [Proc] N. Staffs. Nat. Field Club 

p. 231. 

1 Trans. Koy. Soc. Edinb. vol. xxx. (1881), p. 169, woodcuts figs. 1-3 

2a2 



356 CR0SS0PTEKYG1I. 

1876. Rhizodopsis sauroides, W. J. Barkas, Monthly Rev. Dental 

Surgery, vol. iv. p. 433, figs, lxxxii.-lxxxv. 
1876. Orthognathics, W. J. Barkas, ibid. p. 530, figs, lxxxix., xc. 
1881. Rhizodopsis sauroides, R. H. Traquair, Trans. Roy. Soc. Edinb. 

vol. xxx. p. 169, woodc. figs. 1-3. 
1890. Rhizodopsis sauroides, J. Ward, Trans. N. Staffs. Inst. Mining 

Engin. vol. x. p. 161, pi. viii. figs. 5-8. 
1890. Rhizodopsis sauroides, R. H. Traquair, Proc. Roy. Soc. Edinb. 

vol. xvii. p. 389. 

Type. Scales ; unknown. 

The type species ; much elongated and attenuated in the caudal 
region, attaining a length, of 0*5, but usually about half this size. 
Head with opercular apparatus occupying about one-fifth of the total 
length ; parietal region of cranium longer than broad, much longer 
than the frontal and rostral region ; principal jugulars about three 
times as long as their maximum breadth ; operculum as deep as broad. 
Pelvic fins arising behind the middle point between the pectoral fins 
and the extremity of the caudal ; posterior dorsal fin and the anal 
of equal size, much deeper than long, symmetrical. Scales thin, 
elongate oval, obtusely pointed behind ; the exposed area rhomboidal 
in shape, marked with concentric ridges when abraded. 

Form. Sf Loc. Coal-Measures : English, Welsh, and Scottish Coal- 
fields. 

P. 794. Head and greater portion of trunk, ventral aspect ; Knowles 
Ironstone, Penton, N. Staffordshire. Egerton Coll. 

P. 5196-98. Six portions of head and trunk, some showing fins ; 
Knowles Ironstone, N. Staffordshire. The first shows the 
ring-shaped vertebrae, and the second also the pectoral fins ; 
another exhibits a large, antero-posteriorly elongated scale 
on the inner side of the base of the pelvic fins. 

Purchased, 1885. 

P. 796. Imperfect head and anterior scales ; Deep-mine Ironstone 
Shale, Longton, K". Staffordshire. Egerton Coll. 

P. 3267. Portions of head, pectoral fin, and anterior abdominal 
region, partly in counterpart ; Knowles Ironstone Shale, 
Fenton. JEnnisTcitten Coll. 

P. 3266. Imperfect head, with pectoral fin and anterior scales; 
Low Main Seam, Newsham, near J^ewcastle-upon-Tyne. 

Enniskillen Coll. 

P. 5195. Portions of head, pectoral fin, and anterior scales ; Dale- 
moor Rake Ironstone, Stanton-by-Dale, Derbyshire. 

Purchased, 1885. 



RHIZODONTID^. 357 

P. 4794. Dentary bone, forming the type specimen of Qanolodus 
craggesii, Owen ; registered as obtained from Ruabon. 

Egerton Coll. 

P. 6247. Longitudinal section of jaw prepared for microscopical 
examination ; the type specimen of Gastrodus propositus, 
Owen ; Low Main Seam, Newsham, Northumberland. 

Presented by Sir RicMrd Owen, K.C.B., 1890. 

30571. Extremity of tail of a large fish, showing the second dorsal, 
anal, and greater portion of the caudal fin ; Stanton-by- 
Dale. Purchased, 1856. 

P. 5198 a. Ventral scales and imperfect pectoral fins of a large fish ; 
Hanley. Purchased, 1885. 

42261. Group of fragmentary scales and other remains ; Bilston, 
Staffordshire. Baugh Coll. 

41633. Group of imperfect large scales ; Newcastle-upon-Tyne. 

Presented by T. P. BarJcas, Esq., 1869. 

21421 a. Four scales, inner aspect ; Carluke, Lanarkshire. 

Purchased, 1847. 

41131. Scale, inner aspect ; Carluke. Bryson Coll. 

44148. Scale, outer aspect ; Newcastle-upon-Tyne. 

Purchased, 1873. 

44865. Impression of inner aspect of scale ; Pendleton, Manchester. 
Presented by Benjamin Bright, Esq., 1873. 

P. 4583. Scale, inner aspect ; Ruabon. Enniskillen Coll. 

Rhizodopsis robusta, sp. nov. 

[Plate XVI. fig. 3.] 

I860. Rhizodus hibberti, F. Roemer (errorej, Zeitschr. deutsch. geol. 

Ges. vol. xvii. p. 272, pi. vf. figs. 2, 5 (?non figs. 1, 3). 
1866. Rhizodopsis, J. Young, Quart. Journ. Geol. Soc. vol. xxii. p. 598. 

Type. Scale ; British Museum. 

An imperfectly definable species, distinguished from the type by 
the more robust character of the squamation. The abraded exposed 
portion of each scale is marked by thick rounded ridges, concentric 
with the hinder free border, and sometimes nodose. 

The smaller scale and the tooth figured by Roemer pertain to this 
species ; but the larger scales described and figured by the same 
author are more suggestive of those of Strepsodus. 

Form. Sf hoc. Coal-Measures : Glatz, Silesia. 



35S 



CROSSOPTERYGII. 



P. 4587. Type scale, well preserved, much resembling the original 
of Roemers fig. 2, but less symmetrical ; shown, of three- 
halves the natural size, in PI. XVI. fig. 3 ; Volpersdorf, 
Glatz. Ennislcillen Coll. 

P. 4586. Right operculum, 0*019 in depth, and equally broad, the 
hinder border sharply angulated about its middle point, 
and the lower border twice as long as the upper : Yolpers- 
dorf. Ennislcillen Coll. 

The following specimens also pertain to this genus : — 

P. 789. Two small scales, inner aspect; Coal-Measures, Pictou, 
Nova Scotia. Egerton Coll. 

Genus GYROPTYCHIUS, M'Coy. 
[Ann. Mag. Nat. Hist. [2] vol. ii. 1848, p. 307.] 
Syn. Glyptolepis, L. Agassiz, Poiss. Fos3. V. G. R. 1844, p. 62 (in part). 

Body much depressed anteriorly, with ovoid scales, of which the 
exposed portion is probably covered with a thin film of ganoine, 
while the inner face is marked by a prominent median ridge and 
punctations posteriorly. Head-bones tuberculated. No ossified 
vertebrae. First dorsal fin opposed to the pelvic pair, and the second 
dorsal to the anal ; tail almost diphycercal, the upper lobe of the 
rhomboidal caudal fin being relatively large. 

This genus comprises fishes of small size, and is very closely related 
to RMzodopsis : the scales appear to differ from those of the latter 
merely in the substitution of a prominent long ridge for the median 
inner boss. 

Gyroptychius microlepidotus (Agassiz). 

1844. Glyptolepis microlepidotus, L. Agassiz, Poiss. Foss. V. G. R. p. 65, 

pi. xxi. a. figs. 3-7. 
1848. Gyroptychius anyustus, F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. ii. 

p. 308, woodc. figs. a-c. [Woodwardian Museum, Cambridge.] 
1855. Gyroptychius anyustus, F. M'Coy, Brit. Palaeoz. Foss. p. 596, 

pi. ii. c. fig. 2. 
1860. Gyroptychius anyustus ?, C. H. Pander, Saurodipt., Dendrodont. 

&c. devon. Syst. p. 79, pi. vi. figs. 1-7, pi. vii. figs. 1-3. 
1861.- Gyroptychius, T. H. Huxley, Figs, and Descrips. Brit. Organic 

Remains (Mem. Geol. Surv.), dec. x. p. 3, woodc. fig. 3. 
1875. Gyroptychius anyustus, R. H. Traquair, Trans. Roy. Soc. Edinb. 

vol. xxvii. p. 395. 
1888. Gyroptychius microlepidotus, R. H. Traquair, Geol. Mag. [3] 

vol. v. p. 514. 



RHIZODONTID.E. 359 

Type. Imperfect fishes ; British Museum and Forres Museum. 

The tj-pe species, attaining a maximum length of about 0-3. Head 
with opercular apparatus contained about four and a half times in the 
total length ; parietal region equal to the fronto-ethmoidal in length, 
and the upper part of the anterior extremity of the snout covered 
with separate polygonal plates ; jaws much elongated. Pelvic fins 
arising in advance of a point midway between the operculum and 
the extremity of the tail; dorsal fins higher than long, the first 
smaller than the second, and the latter about equal in size to the 
opposing anal. Scales small. 

Form. 6f Loc. Lower Old lied Sandstone : Nairnshire, Banffshire, 
and Orkney \ 

P. 340. One of the type specimens figured by Agassiz, op. cit. 
pi. xxi. a. fig. 3 ; Lethen Bar, Nairnshire. Egerton Coll. 

50104. Fish, in counterpart, showing portions of several head and 
opercular bones, the clavicles, and fragments of the fins ; 
Lethen Bar. The inner ridge upon the scales is very 
prominent. Purchased, 1879. 

41891. Head and abdominal region of small fish; Tynet Burn, 
Banffshire. Purchased, L870. 

43014. Small fish, in counterpart, showing the obtusely lobate 
pectoral fins and portions of the pelvics, dorsals, and anal, 
but wanting the caudal fin ; Tynet Burn. 

Purchased, 1871. 

43271. Small fish showing portions of the fins ; Tynet Burn. 

Purchased, 1871. 

36071. Scattered scales and various bones of a large fish ; Tynet 
Burn. Purchased, 1861. 

P. 4045. Large well-preserved fish, 0*3 in length, in counterpart; 
Gamrie, Banffshire. The head is vertically crushed, and 
one side of the counterpart exhibits the cranial roof 
from the inner aspect, while the other gives an imperfect 
inner view of the principal jugulars. The parietal and 
fronto-ethmoidal regions of the cranial roof are well sepa- 
rated by a transverse suture ; and there is a median suture 
between the frontals, marked at one point either by a large 
excavation on the inner surface of the closely apposed bones, 
or by a foramen, such as exists in Osteolepis and Diplopterus. 

1 Fragments from the Devonian of Livonia are also assigned to this species by 
E. von Eichwald, Leth. Eossica, vol. i. (1860), p. 1564. 






360 CEOSSOPTERYGII. 

The ethmoidal region is covered with numerous polygonal 
ossifications ; and the forward position of the orbit is well 
shown. The cheek is covered by membrane-bones of which 
the very large posterior element is distinct ; and immedi- 
ately below these occurs the long slender maxilla, provided 
with a series of small teeth. The form and proportions 
of the operculum and suboperculum are also shown, from 
the inner aspect, on the left side. Of the fins, the anal 
and caudal are best preserved ; and a pair of relatively 
large narrow scales seems to occur in advance both of the 
first dorsal and the anal. Purchased, 1883. 

28870, P. 716. Imperfect smaller fish, in counterpart ; Gamrie. 

Purchased, 1854, and Egerton Coll. 

P. 4046. Head and portions of trunk of small fish ; Gamrie. 

Purchased, 1883. 

P. 184-5. Two examples of the head with imperfect trunk, the 
second in counterpart ; Orkney. Purchased, 1881. 

An imperfect scale of an indeterminable genus, from a Lower 
Palaeozoic boulder near Meseritz, Silesia, is named Gijroptychius 
posnaniensis, G. Kade, Programm k. Realschule zu Meseritz, 1858, 
p. 1(5, figs. 6, 7. 



Genus TRISTICHOPTERUS, Egerton. 

[Figs. & Descrips. Brit. Organic Remains (Mem. Geol. Surv. 

1861), dec. x. p. 51.] 

Body much depressed anteriorly, with round or ovoid scales, of 
which the exposed portion is ornamented with short, antero- 
posteriorly directed rugae of ganoine. Head-bones more or less 
tuberculated ; teeth round in section. Ossified ring-shaped ver- 
tebras in the abdominal region. Anterior dorsal fin opposed to the 
pelvic pair, and the posterior dorsal to the anal ; tail heterocercal, 
the caudal fin abruptly truncated posteriorly, having a relatively 
small upper lobe, and the rays at the extremity of the caudal body- 
prolongation extending somewhat beyond the others above and 
below. 

Tristichopterus alatus, Egerton. 

1861. Tristichopterus alatus, Sir P. Egerton, Rep. Brit. Assoc. 1860, 
Trans. Sect. p. 78, and Figs, and Descrips. Brit. Organic Remains 
(Mem. Geol. Surv.), dec. x. p. 51, pis. iv., v. 



RITTZODONTIDiE. 



3(51 



1875. Tristichopterus alatus, R. H. Traquair, Proc. Roy. Soc. Edinb. 

vol. viii. p. 513. 
1875. Tristichopterus alatus, R. H. Traquair, Trans. Roy. Soc. Edinb. 

vol. xxvii. p. 383, pi. xxxii. 

Type. Imperfect fishes ; Museum of Practical Geology and British 
Museum. 

The type species, attaining a length of about 0*3. Maximum 
depth of trunk nearly equal to the length of the head, and contained 
about six and a half times in the total length. Head somewhat 
longer than deep : operculum deeper than broad ; all the bones 
ornamented with granulations, more or less fused into short tor- 
tuous rugse. Pelvic fins about three quarters the size of the pec- 
torals, arising immediately behind the middle point of the trunk, 
and opposed to the somewhat smaller anterior dorsal fin ; posterior 
dorsal and anal fins of nearly equal size, deeper than broad, and 
much larger than the anterior dorsal ; length of caudal fin much 
less than its maximum depth. Scale-ornament very fine and closely 
arranged. 

Form. &f Loc. Lower Old Red Sandstone : Caithness. 

All the specimens mentioned below are comprised in the Peach 
Collection, and were obtained from the neighbourhood of John 
o' Groats. 

42396. Counterpart of one of the type specimens figured by Egerton, 

loc. cit. pi. v. 

42397. Fish, showing well-preserved caudal region, noticed by 

Traquair, loc. cit. 1875, p. 384. 

42398. Imperfect head and anterior part of abdominal region, with 

right pectoral fin. The tubercular and partly rugose 
ornamentation of the head-bones is distinct, and portions 
of the broad, ring-shaped vertebras occur. 

42406. Imperfect trunk with part of the head and large portions 

of the fins. 

42407. Part of the squamation of a large fish, with remains of the 

axial endoskeleton and some of the fin-supports. 

Genus EUSTHENOPTERON, Whiteaves. 

[Canadian Naturalist, n. s. vol. x. 1881, p. 30.] 

Body much depressed anteriorly, with round or ovoid scales, of 
which the exposed portion is ornamented with granulations and 
antero-posteriorly directed rugae. Head-bones more or less tuber- 



3C2 CROSSOPTERYGII. 

culated ; teeth compressed, with a sharp anterior and posterior 
edge. Ossified ring-shaped vertebras in the abdominal region. 
Infraclavicle without an ascending process. Anterior dorsal fin 
opposed to the pelvic pair, and the posterior dorsal to the anal ; 
tail diphycercal or slightly heterocercal, the caudal fin large and 
triangular, abruptly truncated or excavated posteriorly, the upper 
lobe nearly or quite as large as the lower, and the rays at the 
extremity of the caudal body-prolongation extending somewhat 
further backwards than the others. 



Eusthenopteron foordi, Whiteaves. 

1881. Eusthenopteron foordi, J. F. Whiteaves, Canadian Naturalist, n. s. 

vol. x. p. 31, woodc. 
1889. Eusthenopteron foordi, J. F. Whiteaves, Trans. Roy. Soc. Canada, 

vol. vi. sect. iv. p. 79, pi. v. fig. 5, pis. vi., vii., and woodc. fig. 1. 

1889. Phaneropleuron curtum, J. F. Whiteaves {errore), ibid. p. 91, 
pi. x. fig. 1. 

1890. Eusthenopteron foordii, R. H. Traquair, Geol. Mag. [3] vol. vh\ 
p. 17. 

Type. Imperfect fish ; Geological Survey Museum, Ottawa. 

The type species, attaining a maximum length of not less than 
0-6. Head longer than deep, occupying somewhat more than one 
sixth of the total length ; the bones ornamented with granulations 
more or less fused into short tortuous rugse. Pelvic fins much 
smaller than the pectorals, arising about the middle point of the 
trunk, directly opposed to an anterior dorsal fin of nearly equal 
size ; anal and posterior dorsal fins relatively large, very high, 
narrow, and acuminate, equal and opposite, situated close to the 
base of the caudal fin ; caudal fin about as long as deep, having the 
hinder border much excavated above and below the caudal body- 
prolongation. Scale-ornament very delicate. 

. The fine state of preservation in which this species is discovered 
renders it possible to determine many points in the structure of the 
endoskeleton — notably the arrangement of the basal cartilages of 
the fins, which closely resemble those of Tristichopterus. A distinct 
ring of sclerotic plates round the eye is also conspicuous in some of 
the type specimens. 

Form. Sf Loc. Upper Devonian : Scaumenac Bay, P. Q., Canada. 

P. 5219. Fish, 0-25 in length, with imperfectly preserved head, 
displaying all the fins except the pectorals. 

Presented by A. H. Foord., Esq., 1886. 



rhizodontid^:. 363 

P. 5482-84. Three typical small specimens, the third showing 
portions of the vertebrae in the abdominal region. 

Purchased, 1888. 

P. 5976-78. Portions of large individuals. Purchased, 1889. 

The two following genera are proved by their dentition to pertain 
to the Rhizodontidae, but are as yet too imperfectly known for 
precise definition. 

Genus CRICODUS, Agassiz. 

[Poiss. Foss. vol. ii. pt. ii. 1844, p. 156, pi. H. figs. 9-12.] 

Syn. Polyplocodus, C. H. Pander, Saurodipt., Dendrodont. &c. devon. 
Syst. 1860, p. 28. 

Bones of fronto-ethmoidal shield fused into a single piece. Teeth 
rounded in section, with a large pulp-cavity. [Exposed portion 
of scales probably tuberculated.] 

Cricodus incurvus (Duff). 

1842. Bendrodus incurvus, P. Duff, Geol. Moray, p. 68, pi. vi. fig. 11. 
1844. Cricodus incurvus, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. p. 162 

(name only). 
1844. Cricodus incurvus, L. Agassiz, Poiss. Foss. V. G. R. pp. 61, 88, 

pi. xxviii. figs. 4, 5. 

Type. Tooth ; (?) collection of James Powrie, Esq., Reswallie. 

The type species, founded upon a small, stout, recurved tooth 
about 0-013 in length. 

Form. $ Log. Upper Old Red Sandstone: Scat Craig, Elgin. 
Upper Devonian : Riga. 

Not represented in the Collection. 

Cricodus wenjukowi, Rohon. 

1860. Polyplocodus incurvus, C. H. Pander {errore), Saurodipt., Dendro- 
dont. &c. devon. Syst. pp. 82, 84, 86, pi. x. fig. 23, pis. f, g, pi. l. 
figs. 1-5. 

1880. Bendrodus biporcatus, H. Trautschold {errore), Verhandl. russ.- 
kais. mineral. Ges. [2] vol. xv. p. 139, pis. iii.-v. 

1889. Cricodus {Polyplocodus) zvenjukoivi, J. V. Rohon, Mem. Acad. 
Imp. Sci. St.-Petersbourg, [7] vol. xxxvi. no. 14, p. 49, pi. i. figs. 3, 
4, 6, 11, pi. ii. figs. 12, 14, 19. 

(?) 1889. Bendrodus biporcatus, J. V. Rohon {errore), ibid. p. 49, pi. i. 
figs. 1, 9. 

1890. Cricodus, H. Trautschold, Zeitschr. deutsch. geol. Ges. vol. xli. 
p. 629, pis. xxiii.-xxv. 



364 CKOSSOPTERYGII. 

Type. Anterior portion of skull ; University of St. Petersburg. 

A species attaining a larger size than the type, and having the 
teeth almost or quite erect to the apex. Snout gently rounded and 
head-bones externally ornamented with coarse granulations, which 
are rarely fused together into short vermiculating series. 

As remarked by R. H. Traquair (Geol. Mag. [3] vol. vi. 1889, 
p. 491), the specimens described under this name by Rohon as 
entire skulls are merely fragmentary examples of the region in 
advance of the parietal bones. The pair of large teeth shown in 
these fossils is borne by the vomers, and the supposed orbits are 
probably the nasal openings. 

The tuberculated scales described and figured by Rohon (Jog. cit. 
p. 6, pi. i. figs. 7, 8, pi. ii. figs. 13, 15, 16, 17, 18, 20) may pos- 
sibly pertain to this species, but Trautschold remarks (loc. cit. 1890, 
p. 622) that such scales have not yet been found in the same 
localities as the jaws. The specimens are preserved in the School 
of Mines, St. Petersburg, and the University of Dorpat. 

Form. Sf Loc. Devonian : Government of St. Petersburg, and 
(?) Livonia. 

28871. Base of large mandibular tooth affixed to part of the sup- 
porting bone ; locality unknown. Purchased, 1854. 

P. 4733. Two similar specimens, one of them showing the outer 
series of small teeth, and also a detached tooth wanting 
the apex ; River Ssjass. Purchased, 1884. 

To this, or to the following genus, may also probably be assigned 
the species described thus : — 

Cricodus (?) agassizi, M. Lohest, Ann. Soc. Geol. Belg. vol. xv. 
(1888), p. 120, pi. vii. fig. 4, pi. viii. fig. 1.— Upper 
Devonian ; Belgium. [Imperfect dentary and teeth ; 
M. Lohest Collection, Liege.] 



Genus SAURIPTERUS, Hall. 

[Nat. Hist. New York, pt. iv. Geology, 1843, p. 282 (Sauripteris).~\ 

Head-bones, operculum, jugular plates, and clavicular bones or- 
namented with tubercles, more or less fused into short, vermicu- 
lating ridges. Teeth compressed to the base with a pair of sharp 
edges ; pulp-cavity large. Ossified ring-vertebrae present. Scales 
[according to J. S. Newberry] having " the covered portion beauti- 
fully reticulated with large elongated meshes, the exposed portion 



RHIZODONTIDJE. 365 

thickly set with fine conioal or rounded granules, generally without 
linear arrangement." 

The type species of this genus is S. taylori, J. Hall, Nat. Hist. 
New York, pt. iv. Geology, 1843, p. 282, woodc. fig. 130 (1) 
(further noticed by J. S. Newberry, Palaeoz. Fishes N. America, 
1889, p. 112), founded upon portions of a fish from the Catskill 
Group of Blossburgh, Pennsylvania, now in the American Museum 
of Natural History, New York. A personal examination of the 
original specimen has convinced the present writer (Geol. Mag. [3] 
vol. vii. 1890, p. 392) that the arrangement of the cartilages in the 
obtusely lobate pectoral fin and the structure of the teeth suffice to 
determine the Rhizodont character of the fish. It may also be 
added that the writer did not observe the external tubercular scale- 
ornament noted by Newberry, while the reticulated markings sug- 
gested to him the corresponding ornamentation on the exposed 
portion of the scales of Strepsodus (see PI. XY. fig. 1). 

The two following species are only provisionally placed here 
until the discovery of more satisfactory specimens. 



Sauripteriis favosus (Agassiz). 

1844. Glyptosteus favosus, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. p. 179 

(name only). 
1844. Bothriolepis favosa, L. Agassiz, Poiss. Foss. V. G. R. pp. 61, 

100, pi. xxvii. fig. 7, pi. xxviii. figs. 12, 13. 
1860. Dendrodus favosus, E. von Eichwald, Leth. Rossica, vol. i. 

p. 1561 (in part). 
1888. Cricodus (?) favosus, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 515. 
1890. Cricodus (?) favosus, Woodward & Sherborn, Cat. Brit. Foss. 

Yertebrata, p. 48. 

Type. Portions of jaws ; unknown. 

Laniary teeth much compressed, very broad at the base, tapering 
to a slender, faintly recurved apex. External surface of mandible 
coarsely tuberculated • some of the head-bones more finely marked, 
the granulations tending towards arrangement in series. [Scales 
and vertebras unknown.] 

The known examples of the jaws of this species are about 0*25 
in length, and a typical laniary tooth measures 0*015 in height. 
The fragmentary plates from the Russian Old Red Sandstone, 
theoretically associated with the above by Agassiz and Eichwald, 
are too imperfect for determination. 

Form, fy Log. Upper Old Red Sandstone : Perthshire and Elgin. 



366 CEOSSOPTERTGIl. 

P. 3284. Imperfect mandibular ramus in a slab of matrix filled 
with scales of Holoptychius nobilissimus • Clashbennie, 
Perthshire. Enniskillen ColL 



Sauripterus anglicus, sp. nov. 
[Plate XYI. figs. 4-6.] 

Type. Scales and tooth ; British Museum. 

A smaller species than the preceding, known only by scales and a 
detached laniary tooth. The tooth straight and regularly tapering, 
moderately compressed. Scales robust, the exposed portion orna- 
mented with coarse, sparsely and irregularly arranged tubercles. 

Form. <$f Log. Upper Old Red Sandstone : Shropshire. 

P. 200. Type specimen, being a slab of sandstone with about twelve 
scales and an imperfect tooth, one of the former and the 
latter shown, of the natural size, in PI. XYI. figs. 4, 6 ; 
Parlow, Shropshire. Weaver-Jones Coll. 

P. 201. Impression of tooth ; Parlow. Weaver-Jones Coll. 

P. 200 a. Group of large, partially tuberculated scales ; Farlow. 

Weaver-Jones Coll. 

P. 200 b. Still larger scale, with few tuberculations, shown of two- 
thirds the natural size in PI. XYI. fig. 5 ; Parlow. 

Weaver- Jones Coll. 

A hollow conical tooth from the Lower Carboniferous Limestone 
of Armagh, compared with BMzodus and Dendrodus by M'Coy, is 
named Colonodus longidens, P. M'Coy, Ann. Mag. Nat. Hist. [2] 
vol. ii. (1848), p. 5. The original specimen is in the Museum of 
the Geological Society, and is very doubtfully determined (J. W. 
Davis, Trans. Roy. Dublin Soc. [2] vol. i. 1883, p. 523, pi. lxiii. 
fig. 6). 

Another tooth from the Productus-Limestone of the Salt Range, 
India, perhaps referable to the Rhizodontidae, is named Sigmodus 
dubius, W. Waagen, Palseont. Ind. [13] vol. i. (1879), p. 10, pi. i. 
fig. 7. 



osteolepid^;. 367 



Family OSTEOLEPID^E. 

Body fusiform, robust, elongated, and somewhat depressed, with 
rhomboidal scales, slightly overlapping, and covered externally with 
a more or less continuous layer of ganoine. Head and opercular 
apparatus with well-developed membrane- bones ; parietals large 
and separate ; frontals separate, or fused together and with the 
adjoining elements, in which case a median frontal foramen is 
conspicuous ; orbits far forwards ; interoperculum absent ; jugular 
plates comprising one large pair, flanked on either side by a lateral 
series, and with or without a small azygous element in front. 
Dentary bone of mandible fused with well-developed infradentaries in 
the same plane, and forming a thin vertical lamina ; an inner series of 
few large, narrow, shuttle-shaped bones, also fused with the dentary, 
and each supporting a " laniary " tooth ; a pair of similar teeth on 
the roof of the mouth, but the marginal upper dentition feeble. 
Teeth conical, with a pulp-cavity, of which the walls are not 
folded, except quite at the base. Pectoral and pelvic fins obtusely 
lobate ; two remote dorsal fins, the first nearly opposite or directly 
opposite to the pelvic pair ; anal fin single ; caudal fin diphycercal 
or heterocercal. 

In the four typical genera of this family some of the anterior 
rays of each of the fins are relatively robust and covered with 
ganoine. This appearance is due, according to Pander, to the in- 
vestment of the rays with true scales. 

/Synopsis of Genera. 

I. Scales smooth and punctate. 

A pineal foramen ; dorsal fins alternating 

with pelvic and anal ; tail heterocercal . . Osteolepis (p. 368). 
A pineal foramen ; dorsal fins opposed to 

pelvic and anal; tail heterocercal Thursius (p. 373). 

A pineal foramen ; dorsal fins opposed to 

pelvic and anal; tail almost diphycercal 

' and caudal fin rhomboidal Diplopterus (p. 375). 

No pineal foramen ; dorsal fins opposed to 

pelvic and anal ; tail almost heterocercal . . Megalichthys (p. 378). 

II. Scales sculptured. 

Anterior dorsal fin opposed to pelvic pair: 
tail diphycercal , Glypiopomus (p. 






36S CROSSOrTEEYGII. 



Genus OSTEOLEPIS, Valenciennes. 

[Trans. Geol. Soc. [2] vol. iii. 1829, p. 144.] 

Syn. Pleiopterus, L. Agassiz, Poiss. Foss. vol. ii. pt. i. 1835, p. 113. 
Tripterus, F. M'Coy (won Quoy & Gaimard, 1824), Ann. Mag. 

Nat. Hist. [2] vol. ii. 1848, p. 306. 
Triplopterus, F. M'Coy, Brit. Paheoz. Foss. 1855, p. 589. 

Cranial roof-bones in advance of the parietals usually fused into 
a continuous shield, with a median frontal foramen ; an anterior 
median jugular plate present. Teeth rounded in transverse section. 
Ossified ring-shaped vertebrae in the abdominal region. First dorsal 
fin in advance of the pelvic pair, and the second dorsal opposed to 
the space between the pelvics and the anal. Tail strongly hetero- 
cercal ; caudal fin obliquely truncated posteriorly. Scales smooth, 
punctate. 

The most elaborate description of this genus is that of C. H. 
Pander (Saurodipt., Dendrodont. &c. devon. Syst. 1860). Good 
figures of the head had previously been published by Hugh Miller, 
" Footprints of the Creator " (1849), p. 51, figs. 12-15. 



Osteolepis macrolepidotus, Agassiz. 
[Plate XIII. fig. 1.] 

(?) 1829. Osteolepis macrolepidotus, A. Valenciennes, Trans. Geol. Soc. 

[2] vol. iii. p. 144. 
1835. Osteolepis macrolepidotus, L. Agassiz, Poiss. Foss. vol. ii. pt. i. 

p. 119, pi. ii. h. figs. 1-4, pi. ii. c. figs. 5, 6. 
1835. Osteolepis ?nicrolep>idotus, L. Agassiz, ibid. p. 121, pi. ii. c. figs. 

1-4. 
1835. Osteolepis arenatus, L. Agassiz, ibid. p. 122, pi. ii. d. figs. 1-4. 

[British Museum.] 
1841. Osteolepis, H. Miller, Old Ked Sandstone, p. 72, pi. iv. 
1844. Osteolepis major, L. Agassiz, Poiss. Foss. V. G. R. pp. 49, 51, 

pi. xix. figs. 1-3. [British Museum.] 
1848. Osteolepis brevis; F. M'Coy, Ann. Mag. Nat. Hist, [2] vol. ii. 

p. 305. [Woodwardian Museum, Cambridge.] 
1848. Tripterus pollexfeni, F. M'Coy, ibid. p. 306. [Caudal region ; 

"Woodwardian Museum.] 
1855. Osteolepis arenatus, O. macrolepidotus, O. major, and O. micro- 

lepidotus, F. M'Coy, Brit. Palseoz. Foss. pp. 587, 588. 
1855. Osteolepis brevis, F. M'Coy, ibid. p. 587, pi. ii. d. fig. 4. 
1855. Triplopterus pollexfeni, F. M'Coy, ibid. p. 589, pi. ii. d. fig. 5. 
1860. Osteolepis macrolepidotus, C. H. Pander, Saurodipt., Dendrodont. 

&c. devon. Syst. pp. 2 (in part), 7, pi. ii. figs. 2, 6-9, pi. iii. figs. 



OSTKOLEPTD^E. 369 

1-10, 15-21, pi. v. figs. 1-11 (probably in part Thurdus macrolepi- 



1888. Osteolepis macrolepidotus, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 515. 
1890. Osteolepis macrolepidotus, It. H. Traquair, Ann. Mag. Nat. Hist. 

[6] vol. vi. p. 484. 

Type. Imperfect fishes : olim T. S. Traill Collection. 

The type species, attaining a maximum length of about 0*3. 
Head with opercular apparatus contained about four and a half 
times in the total length ; parietal region about two thirds as long 
as the fronto-ethmoidal ; jaws much elongated. Pelvic fins situated 
about halfway between the hinder margin of the operculum and 
the extremity of the tail ; dorsal fins higher than long, separated 
by an interspace equal to twice the length of the base of the second 
dorsal, which is somewhat larger than the first dorsal and similar 
to the anal. Scales large. 

Form. $ Log. Lower Old Red Sandstone : Orkney, Caithness, 
Ross-shire, Cromarty, Nairnshire, and Banffshire \ 

(i.) Orkney Isles (typical 0. macrolepidotus). 

P. 817. Small fish, 0-17 in length, showing the fins; Belyacreugh. 

Egerton Coll. 

P. 3300-1. Three similar specimens, the third exhibiting small, 
slender, well-spaced teeth in the mandible. 

Enniskillen Coll. 

P. 4604, P. 4606. Four imperfect specimens, one wanting the tail. 

Enniskillen Coll. 

41136. Specimen displaying the large scales of the abdominal 
region. Purchased, 1868. 

39195-96. Msh equal in size to the preceding, exhibiting the 
ventral aspect, and a smaller, very imperfect specimen, 
lateral aspect ; Skaill. Purchased, 1865. 

36185. Small fish, showing fins, mostly obscure. Purchased, 1861. 

39253. Small crushed specimen (O. brevis, M'Coy) ; Stromness. 

Purchased, 1865. 
36182-83. Similar fish, obscurely preserved, in counterpart. 

Purchased, 1861. 

1 Scales from the Devonian of St. Petersburg are doubtfully referred to the 
so-called O. major by Agassiz, Poiss. Foss. V. GL E. (1845), p. 138, pi. xxviii. a. 
fig. A, pi. xxxi. a. figs. 8-13. Other fragments of bones and scales from the 
Devonian of Eussia are also ascribed to this species by E. von Eichwald, Leth. 
Eossica, vol. i. (1860), p. 1552. 

PABT II. 2 B 



370 CROSSOrTERYGIJ. 

(ii.) Cromarty. 

P. 6082. llemains of a large fish, wanting the extremity of the 
tail. Presented by F. Harford, Esq., 1889. 

P. 4605. Similar, but more imperfect fish, showing the lobation of 
the pectoral fin. Ennislcillen Coll. 

P. 5065. Fragments of head and scales. 

Presented by J. E. Lee, Esq., 1885. 

19066, 19070-71. Three very imperfect specimens, the first in 
counterpart, the second with a lobate pectoral fin, the 
third showing the inferior aspect of a large head, with 
scattered scales. Purchased, 1845. 

(iii.) Lethen Bar. 

50103. Large fish, in counterpart, showing portions of all the fins, 
the lobate pectorals being especially well preserved. 

Purchased, 1879. 

49181. A much broken specimen, 0*3 in length, in counterpart, 
showing the fins. The fossil is drawn, of two-thirds the 
natural size, in PL XIII. fig. 1 , and exhibits the lobation 
both of the pectoral (]?ct.) and pelvic (jplv.) fins. Parts 
of the median fins are also well preserved ; and the series 
of azygous dorsal ridge-scales is conspicuous in the ante- 
rior abdominal region. Purchased, 1878. 

P. 6083 a-b. Kemains of a large fish showing traces of vertebrae in 
the abdominal region ; also a smaller individual, vertically 
crushed. Presented by F. Harford, Esq., 1889. 

49192. A smaller fish showing traces of the vertebrae in the ab- 
dominal region, the pelvic and median fins. 

Purchased, 1878. 

21547. Two imperfect small specimens, in counterpart; also a 
somewhat larger fish, showing the lobation of the paired 
fins. Presented by Norman McLeod, Esq., 1847. 

20790. Small fish exhibiting the attenuation of the caudal lobe 
and the lobation of the pelvic fins. 

Presented by Colonel Sir Proby T. Cautley, K.C.B., and 

— Gordon, Esq., 1847. 

P. 814. Two small specimens, the first showing the head, pectoral 
fins, and part of the abdominal region, the second ex- 
hibiting all the fins but wanting the head. Egerton Coll. 



OSTfe'OLEPlDJE. 371 

(iv.) Tynet Burn. 

P. 3298. Type specimen of Osteolepis major. Ennislcillen Coll. 

P. 815. Two somewhat larger, imperfect fishes, the second wanting 
the extremity of the tail. Egerton Coll. 

35782. Caudal region of a similar fish. Purchased, 1860. 

37385. Eemains of the head, squamation, and iins of a large 
individual. Purchased, 1863. 

(v.) Gamrie. 

28503-4. Type specimens of Osteolepis arenata, the second figured 
by Agassiz, Poiss. Foss. vol. ii. pi. ii. d. fig. 1, the counter- 
part of the first figured, ibid. pi. ii. d. fig. 3. 

Presented by Sir Roderick I. Murchison, K.C.B.,1S53. 

47871. Small specimen, wanting the first dorsal fin. 

Purchased, 1877. 

P. 3297. Imperfect small specimen. Enniskillen Coll. 



Osteolepis microlepidotus, Pander. 

(?) 1829. Osteolepis micro lepidotus, A. Valenciennes, Trans. Geol. Soc. 

[2] vol. iii. p. 144. 
1860. Osteolepis microlepidotus, C. H. Pander (non Agassiz), Sauro- 

dipt., Dendrodont. &c. devon. Syst. p. 10, and passim, pi. i. figs. 

1-6, 8-10, pi. ii. figs. 1, 3-5, 10-14. 
1888. Osteolepis microlepidotus, K. H. Traquair, Geol. Mag. [3] vol. v. 

p. 516. 
1890. Osteolepis microlepidotus, R. H. Traquair, Ann. Mag. Nat. Hist. 

[6] vol. vi. p. 484. 

Type. Imperfect fishes ; Imperial Academy of Sciences, St. 
Petersburg. 

A small species, attaining a maximum length of about 0*15, and 
differing from O. macrolepidotus in the relatively broader form of 
the cranial shield and the less acute angle of the V-shaped impres- 
sion of the sensory canal behind the pineal foramen. 

Form. Sf Loc. Lower Old Red Sandstone : Caithness. 

33144-47. Four imperfect specimens ; Thurso. Purchased, 1857. 

33158-62. Four imperfect specimens, the first in counterpart; 
Thurso. Purchased, 1857. 

2b2 



r>t'2 CROSSOPTKRYQII. 

39189. Head-bones and greater portion of squamation ; Thurso. 

Bowerbanlc Coll. 

42456. Two imperfect specimens on one slab ; Stone Gun. 

Peach Coll. 

42468. Imperfect large fish ; Thurso. Peach Coll. 

P. 5489. Similar specimen, dorsal aspect, showing head and oper- 
cular bones ; Thurso. Purchased. 

49665-67. Three small specimens, showing the position of the 
fins ; Holburn Head, near Thurso. Purchased, 1879. 

P. 820. Two small specimens ; Thurso. Egerton Coll. 

P. 819. Head and anterior scales, labelled in Hugh Miller's hand- 
writing, thus : " First specimen I laid open on visiting 
Wieland-burn, near Thurso, July 1846. . . This minute 
species of Osteolepis, varying from three to four inches in 
length, is very abundant at Wieland." Egerton Coll. 

P. 3299. Portions of small fish ; Thurso. Enniskillen Coll. 

P. 6081. Two specimens, the smaller displaying the trunk and 
portions of fins, the larger showing parts of the head and 
squamation; Thurso. 

Presented by F. Harford, Esq., 1889. 

The supposed species from Bussia described as follows are based 
upon insufficient material : — 

Osteolepis fischeri, E. von Eichwald, Leth. Rossica, vol. i. (1860), 
p. 1554, pi. lvii. fig. 15 ; C. H. Pander, Saurodipt., Den- 
drodont. &c. devon. Syst. (1860), p. 7 : Megalichthys 
fischeri, E. von Eichwald, Bull. Soc. Imp. Nat. Moscou, 
vol. xvii. (1844), p. 832, and vol. xix. (1846), pt. ii. p. 309, 
pi. x. fig. 34. — Devonian ; Marjina, B. Slawjanka. [Fron- 
tal region of skull ; University of St. Petersburg.] 

Osteolepis intermedia, E. von Eichwald, Bull. Soc. Imp. Nat. 
Moscou, vol. xvii. (1844), p. 831, and ibid. vol. xix. 
(1846), pt. ii. p. 308, pi. x. figs. 30, 31, and Leth. Eossica, 
vol. i. (1860), p. 1553, pi. lvii. fig. 10 ; L. Agassiz, Poiss. 
Eoss. Y. Gr. E. (1845), p. 155. — Devonian ; Marjina, and 
Borowitschi, E. Prikscha. [Scale; University of St. 
Petersburg.] 



ORTEOLEPTD.-K. 373 

Osteolepis nana, E. von Eichwald, Bull. Soc. Imp, Nat. Moscou, 
vol. xvii. (1844), p. 831, and ibid. vol. xix. (1846), pt. ii. 
p. 308, and Leth. Bossica, vol. i. (1860), p. 1555, pi. lvii. 
fig. 9 ; L. Agassiz, Poiss. Foss. V. G. B. (1845), p. 155 ; 
C. H. Pander, Saurodipt., Dendrodont. &c. devon. Syst. 
(I860), p. 7. — Devonian ; Marjina. [Mandibular ramus ; 
University of St. Petersburg. Scales from L. Carboniferous 
Limestone of Podmokloye, Govt. Toula, also doubtfully 
ascribed to this species.] 

Osteolepis tscliershyi, J. V. Bohon, Mem. Soc. Acad. Imp. Sci. St. 
Petersbourg, [7] vol. xxxvi. no. 13 (1889), p. 13, pi. ii. 
figs. 32-35, 39, 41.— Devonian; Valley of Kisil-kul, 50 
versts W. of Minusinsk, Govt, of Tomsk, Siberia. [Scales, 
&c. ; Imperial Academy of Sciences, St. Petersburg.] 



Genus THURSIUS, Traquair. 
[Geol. Mag. [3] vol. v. 1888, p. 516.] 

Head as in Osteolepis and Diplopterus. Dorsal fins opposed to 
the pelvic pair and the anal fin, respectively. Tail strongly hetero- 
cercal ; caudal fin obliquely truncated posteriorly. Scales smooth 
and punctate. 

Thursius macrolepidotus (Sedgwick & Murchison). 

1829. Dipterus macrolepidotus, Sedgwick & Murchison, Trans. Geol. 

Soc. [2] vol. iii. p. 143, pi. xvi. fig. 2 (? figs. 4, 5). 
1835. Dipterus macrolepidotus, L. Agassiz, Poiss. Foss. vol. ii. pt. i. 

p. 115, pi. ii. fig. 4. 
1855. Diplopterax macrolepidotus, F. M'Coy, Brit. Palseoz. Foss. 

p. 587 (in part). 
(?) 1860. Osteolepis, C. H. Pander, Saurodipt., Dendrodont. &c. devon. 

Syst. p. 9, pis. i.-iii. (in part). 
1888. Thursius macrolepidotus, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 516. 

Type. Small fish ; Mus. Geological Society of London. 

The type species, attaining a maximum length of about 0*25. 
Head with opercular apparatus occupying one-fifth of the total 
length; jaws much elongated ; operculum deeper than broad, sub- 
operculum smaller and broader than deep. Pelvic fins situated 
about halfway between the hinder margiu of the operculum and 
the extremity of the tail ; first dorsal fin much smaller than the 



374 CROSSOPTERrGTI. 

second, the latter deeper than long and similar to the opposing anal. 
Scales of moderate size. 

Form. Sf Loc. Lower Old Red Sandstone : Caithness. 

34990, 41359. Large specimen, in counterpart, showing the head 
and abdominal region from above, and the tail from the 
lateral aspect ; Thurso. Many of the bones of the head 
are distinct and appear as in Osteolepis and Diplopterus. 

Purchased, 1860, 1869. 

42462. Small, imperfectly preserved fish, wanting head ; Sandside, 
Reay. Peach Coll. 

42410-11, 42450, 42458-59, 42461, 42463-64, 42466. Seven 
small fishes and the caudal region of two others, of the 
form doubtfully assigned to this species by R. H. Traquair, 
Geol. Mag. [3] vol. v. p. 516 ; South Head, Wick. 

Peach Coll. 

42437, 42439. Somewhat larger imperfect specimen, in counterpart ; 
South Head. Peach Coll. 



Thursius pholidotus, Traquair. 

[Plate XIII. figs. 2, 3.] 

1888. Thursius pholidotus, R. H. Traquair, Geol. Mag. [3] vol. v. 
p. 516. 

Type. Imperfect fish ; Edinburgh Museum. 

A species attaining a somewhat larger size than the type, and 
distinguished by the relatively very large proportions of the scales, 
and the comparative shortness and stoutness of the jaws. 

Form. Sf Loc. Lower Old Red Sandstone : Caithness. 

33173. Impression of head and opercular apparatus, and anterior 
scales ; Holburn Head, near Thurso. Purchased, 1857. 

41361. Imperfect head and trunk, 0*22 in length, wanting the 
pectoral fins. The hinder half of the fossil is drawn, of 
the natural size, in PI. XIII. fig. 2, and the fins are indi- 
cated by the lettering ; the head and abdominal region 
are much crushed and broken, and the former is exposed 
from beneath. Purchased, 1869. 

49664. Much crushed and broken individual, 0-19 in length, in 
counterpart, showing portions of the fins ; Holburn Head. 



OSTEOLF.PIDjE. 



375 



The attenuated caudal lobe is distinctly exhibited, and is 
fringed above by a series of short fin-rays. 

Purchased, 1879. 

33140. Trunk with pelvic, dorsal, and anal fins, and the base of 
the caudal; Thurso. The specimen is shown, of the 
natural size, in PI. XIII. fig. 3, and the fins indicated by 
the lettering. Adjoining each dorsal fin is a very large, 
antero-posteriorly elongated ridge-scalc. 

Purchased, 1857. 

42440. Imperfect head and trunk, wanting the extremity of the 
tail and the anal fin ; South Head, Wick. Large conical 
teeth, simple in section, are shown in the jaws ; and the 
lobation of the paired fins is distinct. Peach Coll. 



Genus DIPLOPTERUS, Agassiz 1 . 

[Poiss. Foss. vol. ii. pt. i. 1835, p. 113.] 

Cranial roof-bones in advance of the parietals fused into a con- 
tinuous shield, with a median frontal foramen ; an anterior azygous 
jugular plate present. Teeth rounded in transverse section. Dorsal 
fins opposed to the pelvic pair and the anal respectively. Tail 
almost diphycercal ; caudal fin unsymmetrically rhomboidal, the 
upper lobe somewhat smaller than the lower. Scales smooth and 
punctate. 

Diplopterus agassizi, Traill. 

1841. Diplopterus agassis, T. S. Traill, Trans. Roy. Soc. Edinb. vol. xv. 

p. 89. 
1844. Diplopterus macrocephalus, L. Agassiz, Poiss. Foss. V. Gr. R. 

p. 54, pis. xvi., xvii. [British Museum and Forres Museum.] 
1844. Diplopterus affinis, L. Agassiz, ibid. pp. 55, 138, pi. xxxi. a. 

fig. 27. 
1844. Diplopterus borealis, L. Agassiz, ibid. p. 55, pi. xviii. fig. 1 (? fig. 2). 

[Olim T. S. Traill Collection.] 
1848. Diplopterus gracilis, F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. ii. 

p. 305. [Woodwardian Museum, Cambridge.] 



1 This generic name is preoccupied (Latreille, 1817, and Boie, 1826), and 
M'Coy accordingly proposed the slightly modified, though essentially identical, 
form Diplopterax. As, however, the fish in question has been universally 
quoted for fifty years under the name of Diplopterus, we are unwilling to 
suggest a change which would necessitate future ichthyologists adopting a dual 
nomenclature. 









376 CROSSOPTERYGII. 

1 8 4 8. Qyroptychius diplopteroides, F. M'Coy, ibid. p. 309. [Wood- 

wardian Museum.] 
1849. Diplopterus, H. Miller, Footprints of the Creator, p. 57, woodc. 

figs. 16, 17. 
1855. Diplopterax affinis and D. agassizii, F. M'Cov, Brit. Palseoz. Foss. 

p. 586. 
1855. Diplopterax gracilis, F. M'Coy, ibid. p. 586, pi. ii. c. fig. 1. 
1855. Diplopterax macrolepidotus, F. M'Coy, ibid. p. 587 (in part). 
1855. Gyroptychius diphpteroides, F. M'Coy, ibid. p. 597, pi. ii. c. fig. 3. 
1860. Diplopterax borealis, C. H. Pander, Saurodipt., Dendrodont. &c. 

devon. Syst. p. 23, pi. iii. figs. 22-27, pi. iv. 
1888. Diplopterus agassizii, R. H. Traquair, Geol. Mag. [3] vol. v. 

p. 516. 
1890. Diplopterus agassizii, R. H. Traquair, Ann. Mag. Nat. Hist. [6] 

vol. vi. p. 484, woodc. fig. 3. 

Type. Imperfect fish ; olim T. S. Traill Collection. 

The type species, attaining a large size, sometimes measuring 0*5 
in length. Head with opercular apparatus occupying somewhat 
less than one quarter of the total length ; operculum deeper than 
broad, suboperculum smaller and broader than deep. Pelvic fins 
situated far behind the middle point of the fish ; first dorsal fin 
much smaller than the second, the latter deeper than long and 
similar in all respects to the opposing anal; caudal fin obtusely 
pointed posteriorly, the origin of its upper lobe precisely opposite to 
that of the lower, and the distance from this point to the origin of 
the first dorsal greater than the total length of the fin. Scales 
relatively large. 

Form. Sf hoc. Lower Old Red Sandstone : Orkney, Caithness, 
Nairnshire, and Banffshire \ 

(i.) Orkney (typical D. agassizi). 

P. 183. Large well-preserved specimen, in counterpart, 0*42 in 
length, wanting the dorsal fins and showing only portions 
of the pelvics and anal. Purchased, 1881. 

P. 3294-a. Two smaller specimens, showing portions of all the 
fins ; Belyacreugh. Eiinislrillen Coll. 

29252 a. Fish 0-29 in length, displaying the fins, but with imper- 
fect head. Purchased. 

P 821. Fronto-ethmoidal portion of cranial shield. Egerton Coll. 

1 The so-called Diplopterus macrocephalus is also supposed to be represented 
by fragments from the Eussian Devonian by L. Agassiz, Poiss. Foss. V. G. B. 
(1845), p. 138, pi. xxxi. a. figs. 1-7, and E. von Eichwald, Letb. Eossiea. 
vol, i. (1860), p. 1556, pi. Ivi. fig. 5. 



OSTEOLEPID^. 377 

39183. Caudal region and hinder half of abdominal region of a 
similar fish. Purchased, 1865. 

P. 831. Portion of squamation of a very large individual, showing 
the inner rib of the flank-scales. Egerton Coll. 

(ii.) Caithness. 

P. 6283. Imperfect head and trunk, 0'32 in length. 

P. 821 a. Plaster cast of cranial shield figured in Miller's ' Foot- 
prints/ p. 58, fig. 17 ; Thurso. Egerton Coll. 

33164, 33168. Two examples of fr onto -ethmoidal shield ; Thurso. 

Purchased, 1857. 

33171. Mandibular ramus ; Holburn Head. Purchased, 1857 . 

(iii.) Lethen Bar (D. macrocephalus). 

P. 551. Counterpart of one of w the type specimens of D. macro- 
cephalus, figured by Agassiz, op. cit. pi. xvi. fig. 3. 

Egerton Coll. 

50101. Greater portion of a fine large specimen, in counterpart, 
showing the remains of two very large teeth in the man- 
dible within the outer small series. The lobation of the 
pelvic fins and the form of the caudal fin are also well 
displayed. Purchased, 1879. 

(iv.) Tynet Burn. 

36008. Imperfectly preserved fish, 0*39 in length. 

Purchased, 1861. 

43012. Smaller fish, showing scattered bones of head and opercular 
apparatus. Purchased, 1871. 

43280. Much crushed similar fish, showing portions of all fins 
except the pectorals. Purchased, 1871. 

36180. Tail of small fish, with median fins. Purchased, 1861. 

(v.) Gamrie (D. affinis). 

P. 4048. Vertically crushed large specimen, in counterpart, about 
0*5 in length. Several bones of the head and opercular 
apparatus are displayed, and ther e are more or less well- 
preserved remains of all the fins. Purchased, 1 883. 



378 cBossopnraYGii. 

28863. Remains of fish, 0*27 in length, ventral aspect. 

Purchased, 1854. 

P. 827, P. 3293. Crushed trunk of fish, wanting head and paired 
fins. Egerton Sf Enniskillen Colls. 

P. 827 a, P. 3293 a. Portions of head and anterior scales of a large 
individual : a close uniform series of conical teeth is seen 
in the mandible. Egerton Sf Enniskillen Colls. 

Under the preoccupied generic name of Gyrolepis, and with the 
specific name of G. posnaniensis, scales much resembling those of 
the foregoing genera, from Lower Palaeozoic boulders near Meseritz, 
Silesia, are described by G. Kade, Programm k. Eealschule zu 
Meseritz, 1858, pp. 17, 18, figs. 8-10. 



Genus MEGALICHTHYS, Agassiz. 
[Poiss. Foss. vol. ii. pt. ii. 1844, pp. 89, 154.] 

Syn. Centrodus, F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. ii. 1848, p. 3, 

and ibid. vol. iii. 1849, p. 140. 
Parabatrachus, R Owen, Quart. Journ. Geol. Soc. vol. ix. 1853, 

p. 67. 
Phomboptychius, J. Young {ex Huxley, MS.), Quart. Journ. Geol. 

Soc. vol. xxii. 1866, p. 604. 
Ganolodus, E. Owen, Trans. Odontol. Soc. vol. v. 1867, p. 354 

(in part). 
Ectosteorhachis, E. D. Cope, Proc. Amer. Phil. Soc. vol. xix. 
1880, p. 56. 

Cranial roof-bones in advance of the parietals rarely fused into a 
continuous shield, without a median frontal foramen ; an anterior 
azygous jugular plate present. Teeth rounded in transverse section. 
Ossified vertebrae in the form of narrow rings. First dorsal fin 
nearly opposite to the pelvic pair, and the second dorsal opposed to 
the anal. Tail intermediate between the diphycercal and hetero- 
cercal stages. Scales more or less smooth and punctate. 

Megalichthys hibberti, Agassiz. 
[Plate XIII. fig. 4.] 

1835. Ichthyolithus clackmannensis, J. Fleming, Edinb. New Phil. 
Mag. vol. xix. p, 314, pi. iv. figs. 1-3. [Portions of Fish ; Edin- 
burgh Museum.] 

1844. Megalichthys hibberti, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. 
p. 90, pis. lxiii., lxiii. «., lxiv. 



0STE0LEPID2E. 



379 



1844. Megalichthys maxillaris, L. Agassiz, ibid. p. 96. [Head ; Leeds 

Museum.] 
1844. Megalichthys hibberti, R. Gamer, Nat. Hist. Stalfordsh. p. 446, 

pi. E. fig. 10. 

1848. Centrodus striatulus, F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. ii. 
p. 4. [Tooth ; Woodwardian Museum, Cambridge.] 

1849. Megalichthys hibberti, W. C. Williamson, Phil. Trans, p. 450, 
pi. xli. fig. 15, pi. xlii. figs. 16-19. 

1853. Parabatrachus colei, R. Owen, Quart. Journ. Geol. Soc. vol. ix. 

p. 67, pi. ii. fig. 1. [Maxilla ; British Museum.] 
1855. Centrodus striatulus, F. M'Coy, ibid. p. 611, pi. iii. G. fig. 1. 
1861. Megalichthys hibberti, J. W. Salter {ex Egerton, MS.), Foss. S. 

Welsh Coalfield (Mem. Geol. Surv.— Iron Ores Gt. Britain, 

pt. iii.), p. 224, pi. i. fig. 16. 

1866. Megalichthys, J. Young, Quart. Journ. Geol. Soc. vol. xxii. 
p. 607. 

1867. Ganolodus sicula, R. Owen, Trans. Odontol. Soc. vol. v. p. 354, 
pi. vii. (assigned to Megalichthys by Hancock and Atthey, Nat. 
Hist. Trans. Northumb. and Durham, vol. iii. 1870, p. 90). [Micro. 
section of tooth ; British Museum.] 

1868. Megalichthys, J. Young, Proc. Nat. Hist. Soc. Glasgow, vol. i. 
p. 174, pi. i. figs. 1-3. 

1873. Megalichthys, T. P. Barkas, Coal-Meas. Palaeont. p. 25, figs. 70- 
82. 

1875. Megalichthys hibberti, J. Ward, [Proc] N. Staffs. Nat. Field Club, 
p. 227, figs. 10,14. 

1876. Megalichthys hibberti, W. J. Barkas, Monthly Rev. Dental Sur- 
gery, vol. iv. pp. 59, 197, 251, figs, lxxi.-lxxix. 

1876. Megalichthys tuberculatus, W. J. Barkas, ibid. p. 61. [Decorti- 
cated bones.] 

1878. Megalichthys hibberti, R. Etheridge, jun., Geol. Mag. [2] vol. v. 
p. 269. 

1884. Megalichthys hibberti, L. C. Miall, Quart. Journ. Geol. Soc. 
vol. xl. p. 347, woodc. figs. 1-4, 6. 

1884. Megalichthys hibberti, R. H. Traquair, Proc. Roy. Phys. Soc. 
Edinb. vol. viii. p. 72, and Geol. Mag. [3] vol. i. p. 118. 

1885. Megalichthys hibberti, L. C. Miall, Description of the Remains 
of Megalichthys in the Leeds Museum. 

1890. Megalichthys hibberti, J. Ward, Trans. N. Staffs. Inst. Mining 
Engin. vol. x. p. 162, pi. ii. figs. 4, 23. 

Type. Head and anterior scales ; Leeds Museum. 

The type species, attaining a length of about 1-5. Head with 
opercular apparatus occupying one-fifth of the total length ; 
parietal region of cranium longer than the fronto-ethmoidal ; length 
of maxilla about three times as great as the depth of the posterior 
expansion ; mandible long and slender, not less than five times as 



380 CROSSOPTERYGII. 

long as deep ; teeth with fine superficial vertical striae ; operculum 
nearly as broad as deep ; each of the pair of jugular plates about 
two and a half times as long as broad, abruptly truncated poste- 
riorly. Ring-vertebrae relatively broad. Ganoino smooth and 
uniformly punctate. 

This is also the type species of the so-called Centrodus, Para- 
batrachus, and Ganolodus. 

Form,. <$f Log. Coal-Measures : all Coal-fields of England, Wales, 
and Scotland (? and Ireland). 

P. 6284. Fish 0-93 in length, wanting the extremity of the tail ; 
Coalbrookdale. The specimen shows the ventral aspect, 
and of fins exhibits only portions of the pectorals, which 
are distinctly obtusely lobate. Purchased* 

P. 5231. Head and scales of anterior portion of trunk ; Dudley. 
The cranial roof-bones, though broken, are well shown, 
and portions of the mandibular rami and opercular 
apparatus are distinct. Purchased, 1886. 

P. 5232. Similar specimen, of larger size ; Dudley. 

Purchased, 1886. 

P. 800. Remains of a small head ; locality unknown. 

Egerton Coll. 

P. 805. Parietal bones and the squamosal and postfrontal elements 
of the right side, most of the superficial ganoine-layer 
removed ; locality unknown. Egerton Coll, 

21421. Fronto- ethmoidal region of skull, somewhat crushed and 
obscured by matrix ; Carluke. Purchased, 1847. 

P. 3306. Similar specimen ; Carluke. EnnisMllen Coll. 

P. 3307. Similar specimen : Longton, Staffordshire. 

EnnisMllen Coll. 

39164. Fragment of premaxilla and dentary ; Coalbrookdale. 

Bowerbank Coll. 

P. 3312. Left maxilla, with portions of other bones and scales, 
wanting most of the superficial ganoine ; Dalkeith. 

EnnisMllen Coll. 

P. 3313. Fragmentary maxilla, associated with scales ; Dalkeith. 

Enniskillen Coll. 



0STE0LEPIDJ3. 381 

29673. Imperfect right maxilla, inner aspect, associated with a 
scale, forming the type specimen of Parabatrachus colei, 
Owen, loc. cit., and assigned to Megalichthys hibberti by 
J. Young, loc. cit., 1868 ; Carluke. Enniskillen Coll. 

21421 a. Portion of maxilla showing teeth ; Carluke. 

Purchased, 1847. 

P. 3309. Group of head-bones, including mandibular rami ; Carluke. 

Enniskillen Coll. 

P. 3304-5, P. 3308. Two large mandibular rami, about 0-23 in 
length, and two fragments, showing some of the teeth ; 
Carluke. Enniskillen Coll. 

21222 g. Portion of large mandibular ramus, associated with scales ; 
Carluke. Purchased, 1847. 

P. 798. Eight mandibular ramus, about 0*2 in length ; Low Main 
Seam, Newsham, near Newcastle-upon-Tyne. 

Egerton Coll. 

P. 4591. Imperfect small mandibular ramus; Lowmoor, Yorkshire. 

Enniskillen Coll. 

P. 3310. Anterior half of small left mandibular ramus, with well- 
preserved teeth; Knowles Ironstone Shale, Penton, N. 
Staffordshire. Enniskillen Coll. 

49611. Small right mandibular ramus, associated with scales and 
portions of bones ; Staffordshire. Purchased, 1878. 

P. 800 a, P. 806. Pour fragments of mandible ; locality unknown. 

Egerton Coll. 

21975. Left mandibular ramus of young, measuring 0*048 in length, 
and about five times as long as deep ; Carluke. 

Purchased, 1848. 

21423. Numerous detached teeth ; Carluke. Purchased, 1847. 

P. 6243. Longitudinal section of tooth, prepared for microscopical 
examination, the type of Ganolodus sicula, Owen ; News- 
ham, near Newcastle-upon-Tyne. 

Presented by Sir Richard Owen, K.C.B., 1890. 

33299-a, b. Operculum wanting part of the hinder border, and a 
crushed and broken example of the same bone ; also an 
undetermined bone : Carluke. Purchased, 1858. 



382 CR0SS0PTEKYG1I. 

21421 b, 21975 a, b. Lateral jugular, one of the principal jugulars 
associated with scales, and another slab of shale showing 
undetermined bones with scales and a vertebra ; Carluke. 

Purchased, 1847-48. 

21421 c, d. Two slabs of shale, showing well-preserved ring- 
vertebrae, with neural and haemal arches, associated with 
scales ; Carluke. Purchased, 1847. 

P. 3326. Large ring-vertebrae associated with scales ; Carluke. 

EnniskiUen Coll. 

P. 3327. Scales associated with a ring-vertebra ; Dalkeith. 

EnniskiUen Coll. 

P. 3329. Three ring-vertebrae; Longton. EnniskiUen Coll. 

45858. Left clavicle, wanting most of the superficial ganoine; 
Newsham. Purchased, 1874. 

P. 256 a. Portion of upper caudal lobe and fin ; English Coal- 
pleasures. Presented by J. Wood-Mason, Esq., 1880. 

P. 4471. Fragment of naturally-arranged squamation ; Dalkeith. 

EnniskiUen Coll. 

20699, 21222 h. Scales ; Carluke. Purchased, 1847. 

P. 4472. Imperfect scales in Cannel Coal ; Wigan. EnniskiUen Coll. 

41251 a. Scales ; Upper Coal-Measures (Sjrirorbis Limestone), Ard- 
wick, Manchester. Purchased, 1869. 

P. 242. Group of scales ; Knowles Ironstone Shale, Pent on, North 
Staffordshire. Weaver-Jones Coll. 

P. 3328. Two groups of scales; Knowles Ironstone Shale, Fenton. 

EnniskiUen Coll. 

P. 807. Group of scales ; Dudley. Egerton Coll. 

P. 4090. Detached scales and teeth ; Gubbin Ironstone Shale, Old 
Hill, near Stourbridge. 

Presented by Horace Pearce, Esq., 1883. 

P. 2286. Scales and miscellaneous remains ; Carluke. 

Presented by G. Griffiths, Esq.. 1882. 

38007. Imperfect small fish, probably young of 31. hibberti, noticed 
by R. H. Traquair, Geol. Mag. [3] vol. i. (1884), p. 118; 



OSTEOLEPID.E. 383 

Airdrie. The head and abdominal region are very im- 
perfectly preserved, but the caudal region is well exhibited 
from the lateral aspect, and is shown, of the natural size, 
in PL XIII. fig. 4. Impressions of the opercular appa- 
ratus occur, and there are fragments of the pectoral fins ; 
but the only other feature of interest in the anterior por- 
tion of the fish is the " decortication " of the scales, which 
consequently exhibit the characteristic ornamentation of 
the so-called Rhomboptychius. The removal of some of 
the scales upon the tail exposes a few of the vertebrae (v.), 
with their neural and haemal arches ; and impressions 
of several of the latter are distinct at the base of the 
caudal fin (c). In the front of each median fin there are 
large fulcral scales at the base, and a few of the anterior 
fin-rays are coated with ganoine ; all the rays are broad, 
articulated, and closely arranged. The lobe of one of the 
pelvic fins (plv.) is distinct, and the dorsal fins (cl x , d 2 ) 
are opposed to this and the anal (a) respectively ; the 
posterior portion of the caudal fin (c) is unfortunately 
missing. Purchased, 1864. 

P. 3325. Imperfect fish, wanting fins, about 0*7 in length, doubt- 
fully pertaining to this species : Castlecomer, Kilkenny, 
Ireland. Portions of some head and opercular bones 
and impressions of others are seen ; and the left clavicle 
and infraclavicle occur, destitute of the superficial layer 
of ganoine. Enniskillen Coll. 

P. 3325 a. Partly scattered squamation of a similar fish ; Castle- 
comer. Ennishillen Coll. 

P. 2292. Coprolite, with scales doubtfully of this species ; Govan, 
near Glasgow. Presented by George Griffiths, Esq., 1852. 

Megalichthys coccolepis, Young. 

[Plate XIII. fig. 5.] 

1870. Megalichthys coccolepis, J. Young, Rep. Brit. Assoc. 1869, Trans. 
Sect. p. 102. 

1875. Megalichthys coccolepis, J. Ward, [Proc] N. Staffs. Nat. Field 
Club, p. 229. 

1876. Megalichthys coccolepis, W. J. Barkas, Monthly Rev. Dental 
Surgery, vol. iv. p. 60. 

1890. Megalichthys coccolepis, J. Ward, Trans. N. Staffs. Inst. Mining 
Engin. vol. x. p. 165. 



384 CROSSOPTEUYGTT. 

Type. Scales and head-bones ; collection of James Thomson, Esq., 
Glasgow. 

Proportions of bones and scales, so far as known, resembling 
those of the type species. Ganoine covered with numerous small, 
closely-arranged, blunt tuberculations. 

Form. SfLoc, Coal-Measures : Lanarkshire, Northumberland, and 
Staffordshire. 

P. 4590. Left mandibular ramus, 0*135 in length, but imperfect 
anteriorly and exhibiting only the bases of the teeth : 
also an associated dermal plate and scale ; Low Main 
Seam, Newsham, near Newcastle-upon-Tyne. 

Enniskillen Coll, 

P. 5494, P. 5137. Hinder portion of a similar mandibular ramus 
and a fragment ; Newsham. Of the first specimen, a 
portion of the ornament is shown, five times the natural 
size, in PI. XIII. fig. 5. 

Presented by William Dinning, Esq., 1888. 



Megalichthys intermedius, sp. nov. 

1866. Rhomboptychius, J. Young (ex Huxley, MS.), Quart. Journ. Geol. 

Soc. vol. xxii. pp. 597, 604, woodc. figs. 1, 2. [Imperfect fish ; 

Andersonian Museum, Glasgow.] 
(?) 1870. Megalichthys rugosus, J. Young, Rep. Brit. Assoc. 1869, 

Trans. Sect. p. 102. [Specifically indeterminable decorticated 

bones; collection of James Thomson, Esq., Glasgow.] 
1875. Rhomboptychius, J. Ward, [Proc] N. Staffs. Nat. Field Club, 

p. 230, fig. 6. 
(?) 1875. Megalichthys rugosus, J. Ward, ibid. p. 229. 
1890. Megalichthys rugosus, Woodward & Sherborn, Cat. Brit. Foss. 

Vertebrata, p. 118. 
1890. Rhomboptychius, J. Ward, Trans. N. Staffs. Inst. Mining Engin. 

vol. x. p. 166, pi. ii. figs. 6, 24, pi. viii. fig. 9. 

Type. Portions of head ; British Museum. 

A species attaining a somewhat larger size than the type. Man- 
dible elongated, not less than five times as long as deep ; posterior 
expansion of maxilla relatively deep ; larger teeth smooth or finely 
striated, often transversely banded, and sometimes with one or two 
rings of slight, vertically elongated indentations. Each of the pair 
of jugular plates about two and a half times as long as broad, 
rounded or obliquely truncated posteriorly. Ring-vertebrae much 
more slender than in M. hibberti ; superficial ganoine upon the 



OSTEOLKPlDiE. , 385 

scales and head-bones apparently thinner than in the last-named 
species. 

Though regarded by Young as the type of a distinct genus, 
llhomboptychius, on account of the characters of the scales and 
teeth, the specimens mentioned below prove tbat no sufficient basis 
for the generic separation of this species from Megalichthys can yet 
be established. 

Form. 4" Loc. Coal-Measures : South Scotland and North Stafford- 
shire. 

37320-21. Two slabs of shale exhibiting various bones and scales ; 
Airdrie, Lanarkshire. The first specimen, which is to be 
regarded as the type, shows the left mandibular ramus 
and other portions of the jaws with teeth, the oral aspect 
of some of these bones being covered with numerous 
small, closely-arranged dental tubercles, as described by 
Young ; the greater portion of the operculum is seen 
from the inner aspect, and several scales are preserved, 
showing not only fragments of the superficial ganoine- 
layer, but also, in some instances, a well-marked median 
rib on the inner side ; a few of the characteristic slender 
ring-vertebrae also occur. The second specimen shows 
the pair of jugular plates and portions of jaws, with 
teeth, from the inner aspect ; the larger teeth are trans- 
versely banded, and the external aspect of the bones is 
covered with ganoine. Purchased, 1863. 

P. 3324. Jugular plate; Gubbin Ironstone Shale, Shelton, North 
Staffordshire. Enniskillen Coll. 

37974-75. Two slabs with miscellaneous remains ; Airdrie. 

Purchased, 1863. 

P. 3303. Group of head-bones ; Carluke. Enniskillen Coll. 

P. 4465. Small slab with miscellaneous remains ; Carluke. 

Enniskillen Coll. 

P. 4802. Greater portion of right maxilla with teeth ; Palace Craig 

Ironstone, Airdrie. Armstrong Coll., transferred from 

Mus. Science Sf Art, Edinburgh, 1884. 

39248. Portion of maxilla ; Airdrie. Purchased, 1865. 

37973, 38010. Portions of two large mandibular rami showing the 
bases of teeth, one associated with detached scales ; 
Airdrie. Purchased, 1863-64. 

PAET II. 2 c 



3S6 CROSSOPTERYGII. 

38556, 42037, 46023. Three fragments of mandible ; Airdrie. 

Purchased, 1864, 1870, 1874. 

P. 5179. Portion of mandibular ramus wanting the external layer 
of ganoine, displaying a portion of the series of small 
teeth, and three large inner teeth, of which the second 
(i. e. that upon the most anterior internal dentary bone) 
shows the indentations characteristic of il Jthomboptychius" '; 
Deep Mine, Longton, North Staffordshire. This specimen 
is noticed by J. Ward, Trans. N. Staffs. Inst. Mining 
Engin. vol. x. p. 167. Purchased, 1885. 

P. 3311. Six large teeth ; Deep Mine, Longton. EnnisJcillen Coll. 

P. 249. Large, transversely-banded tooth ; Knowles Ironstone, 
Fenton, North Staffordshire. Weaver- Jones Coll. 

P. 793. Large transversely banded and indented tooth ; Deep Mine, 
Longton. Egerton Coll. 

P. 3279. Three ring-vertebra3 ; Longton. EnnisJcillen Coll. 

40175, 42001. Scales and bone-fragments, the second group doubt- 
fully of this species ; Airdrie. Purchased, 1866, 1870. 

46024-25. Group of small " decorticated " scales, and two asso- 
ciated scales of the lateral line ; Airdrie. 

Purchased, 1874. 

P. 361. "Decorticated" scales; Airdrie. Purchased, 1881. 

P. 4801. Similar large scales; Airdrie Blackband, Carnbroe. 

Armstrong Coll. — Transferred from Edinburgh Museum, 1884. 

P. 3314. Group of similar scales, a few showing the ganoine layer ; 
Dalkeith. EnnisJcillen Coll. 

P. 802-4. Three groups of similar scales, some showing the ganoine 
layer ; locality unknown. Egerton Coll. 



Megalichthys laticeps, Traquair. 

1836. Megalichthys, S. Hibbert (in part), Trans. Roy. Soc. Edinb. 

vol. xiii. pi. xi. iigs. 2-8. 
(?) 1844. Diplopterus robertsoni, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. 

p. 162 (name only). 
1884. Megalichthys laticeps, R. H. Traquair, Proc. Roy. Phys. Soc. 



OSTEOLEPID^i. 387 

Edinb. vol. viii. p. 67, pi. iv., and Geol. Mag. [3] vol. i. p. 115, pi. v. 
figs. 1-6. 
1890. Megalichthys laticeps, R. H. Traquair, Proc. Roy. Soc. Edinb. 
vol. xvii. p. 389. 

Type. Portions of fishes ; Edinburgh Museum. 

A comparatively small species. Parietal region of cranium broad, 
shorter than the fronto-ethmoidal region ; length of maxilla more 
than four times as great as the depth of its posterior expansion ; 
mandible more than four times as long as deep ; each of the pair of 
jugular plates about two and a half times as long as broad, abruptly 
truncated posteriorly. Pelvic fins situated far behind the middle of 
the body. Ganoine smooth and uniformly punctate. 

Form. Sf Log. Calciferous Sandstones : Burdiehotise, near Edin- 
burgh, and Burntisland, Fifeshire. 

All the following specimens were obtained from the Burdiehouse 
Limestone. 

P. 733-4. A series of fragments of fishes, one labelled Megalichthys 
hibberti in Agassiz's handwriting, and some showing well- 
preserved fins. Egerton Coll. 

37380. Portion of right mandibular ramus showing dental tubercles 
on the splenial bone. Purchased, 1863. 

14058, 15537. Scales. Purchased. 

47720. Group of scales. Presented by Dr. Lauder Lindsay, 1876. 

P. 4470. Two groups of scales, one labelled Megalichthys hibberti in 
Agassiz's handwriting. Ennishillen Coll. 

Megalichthys pygmseus, Traquair. 

1841. Megalichthys hibberti (" young "), E. W. Binney, Trans. Man- 
chester Geol. Soc. vol. i. p. 163, pi. v. figs. 1, 2. 

1844. Diplopterus carbonarius, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. 
p. 162 (name only). [Scales, &c. ; British Museum.] 

1879. Megalichthys pygmesus, R. H. Traquair, Mem. Geol. Surv. Scot- 
land, Expl. to Sheet 31 ; p. 76 (name only). 

1890. Megalichthys pygmceus, R. H. Traquair, in J. Ward, Trans. N. 
Staffs. Inst. Mining Engin. vol. x. p. 164, pi. vi. figs. 7, 8. 

Type. Mandibular ramus ; Geological Survey of Scotland. 

An imperfectly known species of very small size. Mandible three 
and a half times as long as deep; each of the pair of jugular plates 
also three and a half times as long as broad, pointed in front, 
rounded behind. Scales relatively thick, coarsely punctate. 

2c2 



388 CROSSOPTERYGII. 

It remains uncertain whether or not this is the immature form 
of M. hibberti. 

Form. Sf Loc. Coal-Measures : Lanarkshire, Northumberland, 
Yorkshire, Derbyshire, and Staffordshire. 

46811. Rostral portion of cranium ; English Coal-Measures. 

Cunnington Coll. 

P. 5138. Mandibular ramus, 0*011 in length; from shale accom- 
panying Townley Seam, Wylam-on-Tyne. 

Presented by William Dinning, Esq., 1886. 

P. 828 b. Portion of similar mandibular ramus, noticed by Traquair, 
loc. cit. 1890, p. 164 ; Leeds. Egerton Coll. 

P. 828 a, c, e. Fragment and two scales, the first labelled Diplo- 
jpterus carbonarius by Agassiz ; Leeds. Egerton Coll. 

P. 3302. Fragments of head and scales ; Leeds. Enniskillen Coll. 

Species not represented in the Collection have also been partially 
defined under the following names : — 

Megalichthys ciceronius : Ectosteorhacliis ciceronins, E. D. Cope, 

Proc. Amer. Phil. Soc. vol. xx. (1883), p. 628.— Permian ; 

Texas. [Imperfect cranium ; collection of Prof. E. D. 

Cope, Philadelphia.] 
Megalichthys Icevis, R. H. Traquair, Proc. Roy. Soc. Edinb. vol. 

xvii. (1890), p. 391. — Calciferous Sandstone ; Straiton, 

near Edinburgh. [Imperfect fishes ; Edinburgh Museum.] 
Megalichthys nitidus : Ectosteorhacliis nitidus, E. D. Cope, Proc. 

Amer. Phil. Soc. vol. xix. (1880), p. 56. — Permian ; Texas. 

[Head and abdominal region, the type of Ectosteorhacliis ; 

collection of Prof. E. D. Cope.] 

Detached scales indistinguishable from those of Megalichthys 
hibberti have also been discovered in the Coal-Measures of Ohio 
(J. S. Newberry, Rep. Geol. Surv. Ohio, vol. i. pt. ii. 1873, p. 343, 
pi. xl. fig. 3) and Nova Scotia (Psammodus bretohensis, J. F. 
Whiteaves, Canadian Naturalist, n. s., vol. x. 1881, p. 36). The 
error involved in the latter determination has been pointed out to 
the writer by Mr. J. F. Whiteaves, in the Museum of the Canadian 
Geological Survey, Ottawa, where the type specimen is preserved. 

A doubtful scale from the Lower Permian of Kounova, Bohemia, 
is also named Megalichthys nitens, A. Fritsch, Fauna der Gaskohle, 
vol. ii. (1889), pi. lxxxviii. figs. 15, 16. 



OSTEOLEPIDiE. 389 

It seems probable that the following insufficiently characterized 
genera and species are founded upon scales of Osteolepidoo : — 

Plintholepis retrorsa, H. Romanowsky, Bull. Soc. Imp. Nat. 

Moscou, vol. xxxvii. (1864), pt. ii. p. 169, pi. iv. fig. 37. 

— Carboniferous Limestone ; Government of Toula. 
Sporolepis pyriformis and S. erassa, H. Romanowsky, ibid. 

p. 169, pi. iv. figs. 38 a, b.— Ibid. [? Fulcral scales.] 



Genus GLYPTOPOMUS, Agassiz. 

[Poiss. Foss. Y. G. R. 1844, p. 57.] 

Syn. Platygnathus, L. Agassiz, ibid. p. 77 (in part). 

Glyptolcemus, T. H. Huxley, in Anderson's Dura Den, 1859, p. 63. 

Head-bones in advance of the parietals not fused into a continuous 
shield ; frontals separate, with a median foramen ; head-bones, 
operculum, and jugular plates ornamented with irregular reticula- 
ting rugas or fused series of tubercles, apparently coated with a very 
thin layer of ganoine ; no anterior median jugular plate. Anterior 
dorsal fin opposed to the pelvic pair and the posterior to the anal ; 
tail diphycercal, with a rhomboidal caudal fin. Scales with broad 
overlapped border, externally ornamented with tubercles and reti- 
culating rugae of ganoine. 

The characteristic external ornamentation of this genus seems to 
be due to the special development of the rugosities so characteristic 
of Megaliclithys when the superficial ganoine is removed. Though 
ganoine is sometimes stated to be absent upon the dermal skeleton 
of Glyptopomus, the present writer is of opinion that an extremely 
thin layer occurs. 

Glyptopomus minus, Agassiz. 

1844-45. Platygnathus minor, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. 
p. 162 (name only), and Poiss. Foss. V. G. R., lettering of 
pi. xxvi. 

1844. Glyptopomus minor, L. Agassiz, Poiss. Foss. V. G. R. p. 57. 

1859. Glyptopomus minor, J. Anderson, Dura Den, p. 55, pi. ii. 

1866. Glyptopomus minor, T. H. Huxley, Figs. & Descrips. Brit. Or- 
ganic Remains (Mem. Geol. Surv.), dec. xii. p. 4, pi. i. figs. 1, 3, 4. 

Type. Imperfect head and trunk, dorsal aspect ; British Museum. 

The type species, attaining a length of about 0*4. Head with 
opercular apparatus contained about five times in the total length : 
jaws much elongated ; principal jugular plates rapidly tapering and 



890 CROSSOPTERYGII. 

acuminate in front, nearly two and a half times as long as their 
maximum breadth. Scales large and thick, covered with even 
rounded ridges forming a complete reticulation. 

The finest known example of this fish, described by Huxley in 
1866, is now in the Elgin Museum. 

Form, fy Loc. Upper Old Red Sandstone : Fifeshire and Elgin. 

26118. Type specimen, described and figured by Agassi/, and Ander- 
son ; Dura Den, Eifeshire. Purchased, 1851. 



Glyptopomus sayrei, Newberry. 

1878. Glyptopomus sayrei, J. S. Newberry, Ann. New York Acad. 
Sci. vol. i. p. 189. 

1889. Glyptopomus sayrei, J. S. Newberry, Palaeoz. Fishes N. America, 
p. 116, pi. xviii. fig. 1. 

Type. Head, pectoral fins, and anterior abdominal region, ventral 
aspect ; Lehigh University, Pennsylvania. 

A species closely related to G. minor, known only by the type 
specimen. The " triangular accessory jugulars ' ; ' of G. minor noted 
by Newberry are the infraclavicles, met with in all Crossoptery- 
gians sufficiently well preserved. 

In this fossil the lateral jugular plates are shown, and it is 
suggested (op. cit. 1889, p. 118) that if such plates eventually prove 
to be absent in the typical G. minor, the fish may be regarded as 
representing a distinct genus, Glyptognaihus. 

Form. Sf Loc. Catskill Group : Susquehanna River, near mouth of 
Mehoopany River, Pennsylvania. 

Not represented in the Collection. 

Glyptopomus kinnairdi, Huxley. 

1859. Glyptolcemus Jcinnairdi, T. H. Huxley, in Anderson's Dura Den, 

p. 63, pis. iii., iv. 
1859. Diplopterus dalgleisiensis, J. Anderson, ibid. p. 71, pi. i. fig. 4. 

[Head ; Museum of Practical Geology.] 

1861. Glyptolcemus kinnairdi, T. H. Huxley, Figs. & Descrips. Brit. 
Organic Remains (Mem. Geol. Surv.), dec. x. p. 41, pis. i., ii. 

1862. Glyptolcemus, J. Powrie, Quart. Jo urn. Geol. Soc. vol. xviii. 
p. 435. 

(?) 1888. Glyptolcemus kinnairdi, M. Lohest, Ann. Soc. Geol. Belg. 
vol. xv. p. 158, pi. ix. figs. 6, 7. [Scales ; M. Lohest Collection, 
Liege.] 

1890. Glyptolcemus kinnairdi, Woodward & Sherborn, Cat. Brit. Foss. 
Vertebrata, p. 85. 



ONYCH0D0NTID.E. 



391 



1890. Glyptokemus kinnairdi, R. H. Traquair, Proc. Roy. Soc. Edinb. 
vol. xvii. p. 389. 

Type. Fishes ; Museum of Practical Geology. 

A very slender species, attaining a maximum length of about 0*4. 
Head with opercular apparatus more than twice as long as its 
maximum depth, comprised about five times in the total length. 
Parietal region long and narrow, exceeding the frontal region in 
length ; jaws much elongated ; principal jugular plates rapidly 
tapering and acuminate in front, three and a half times as long 
as their maximum breadth. Pelvic fins remote, arising midway 
between the pectorals and the extremity of the caudal. Scales 
relatively smaller than in G. minor, these and the head-bones orna- 
mented with sharper, more irregularly developed reticulating rugae 
than in the latter species. 

This is the type species of the so-called Glyptolcemus. 

Form, fy Loc. Upper Old Red Sandstone : Fifeshire. (?) Upper 
Devonian : Belgium. 

26117 a. Head and imperfect trunk, ventral aspect, showing a 
fragment of the left pectoral fin ; Dura Den. The speci- 
men is associated with the anterior half of the head of 
another individual, and remains of Holoptychius. 

Purchased, 1851. 

P. 6285. Fragment of trunk ; Dura Den. EnnisJcillen Coll. 



Family ONYCHODONTID^l. 

Scales cycloidal, deeply overlapping. Head and opercular appa- 
ratus with well-developed membrane- bones. Dentary bone of 
mandible thin and deep, bearing a single close series of large conical 
teeth, flanked by an outer series of very minute teeth ; an azygous 
scroll-like element occupying a groove in the dentaries at their 
symphysis. Teeth plicated only at the base, with a central cavity ; 
dentary teeth tipped only, presymphysial teeth completely enve- 
loped with enamel. 

The single known genus of this family, Onychodus, has hitherto 
been found only in a fragmentary condition. The form and pro- 
portions of the trunk and fins thus await discovery. 



392 CEOSSOPTEHTGn. 

Genus ONYCHODUS, Newberry. 
[Bull. National Institute, 1857, p. 5.] 
External bones and scales ornamented with tuberculations, more 
or less conical and radiately grooved. Clavicle triangular in shape, 
with relatively large inferior limb ; infraclavicle without an elon- 
gated ascending process. Presymphysial bone very prominent, its 
teeth much larger than thoso of the dentary. 

Onychodus sigmoides, Newberry. 

1857. Onychodus sigmoides, J. S. Newberry, Bull. National Inst. p. 5. 
1862. Onychodus hopkinsi, J. S. Newberry {errore), Amer. Journ. Sci. 

[2] vol. xxxiv. p. 77, woodc. fig. 3. 
1873. Onychodus sigmoides, J. S. Newberry, Rep. Geol. Surv. Ohio, 

vol. i. pt. ii. p. 299, pi. xxvi. figs. 1-5, pi. xxvii. figs. 1, 2. 
1889. Onychodus sigmoides, J. S. Newberry, Palseoz. Fishes N. America 

(Mon. U.S. Geol. Surv. no. xvi.), p. 56, pi. xxxvi. figs. 1-4, 

pi. xxxvii. figs. 1-10. 

Type. Portions of mandible ; Columbia College, New York. 

The type species of large size, the longest presymphysial teeth 
measuring 0*058 in length. Tuberculations upon scales conical and 
prominently sculptured, those upon the external bones rounder, 
somewhat smoother, and more numerous. Dentary teeth regular 
in size and shape throughout the greater part of the thickened oral 
border, each tumid in its basal half and tapering to the very slender 
enamelled apical portion ; presymphysial teeth sigmoidally curved, 
stout, with a large central cavity, nearly regular in size, and loosely 
attached to the supporting bone. 

Several detached bones of this species, in the Museum of Colum- 
bia College, New York, are figured by Newberry, op. cit., 1889. 

Form. Sf Log. Corniferous Limestone (Lower Devonian) : Ohio. 

Not represented in the Collection. 

Onychodus anglicus, A. S. Woodward. 

[Plate XY. fig. 1.] 

1888. Onychodus anglicus, A. S. Woodward, Geol. Mag. [3] vol. v. 
p. 500, woodc. 

Type. Presymphysial bone ; Oxford Museum. 

A very small species, known only by the presymphysial bone, 
which is remarkably in-rolled in the form of a scroll at its inferior 
extremity. Presymphysial teeth tumid in the basal half, much 



ONYCTI0D0NTID.2E. 393 

attenuated in the distal half, firmly fixed to the supporting hone, 
and with a relatively small internal cavity ; the teeth diminishing 
rapidly in size downwards in the series. 

Form, fy Loc. Lower Old Red Sandstone : Herefordshire. 

Fig. 52. 




Onychodus anglicus, A. S. Woodw. — Presymphysial dentition, side view 
(partly in section), twice nat. size. [Oxford Museum.] 

P. 6252. The inferior portion of a presymphysial bone, exhibited 
in vertical section in matrix, shown of twice the natural 
size in PI. XV. fig. 1 ; Bush Pitch, Ledbury. 

Presented by George H. Piper, Esq., 1890. 

The following species are also known only by remains of the 
presymphysial dentition, of which there are no examples in the 
Collection : — 

Onychodus arctieus, A. S. "Woodward, Eep. Brit. Assoc. 1889, 
p. 585, and Geol. Mag. [3] vol. vi. (1889), p. 499.— 
Lower Devonian ; Spitzbergen. [B-oyal State Museum, 
Stockholm.] 

Onychodus hopMnsi, J. S. Newberry, Eep. Geol. Surv. Ohio, 
vol. i. pt. ii. (1873) p. 302, and Palaeoz. Fishes N. America 
(Mon. U. S. Geol. Surv. no. xvi. 1889), p. 99.— Chemung 
Group (Upper Devonian) ; Delaware Co., New York. 

Onychodus ortoni, J. S. Newberry, Palseoz. Pishes N. America 
(Mon. U.S. Geol. Surv. no. xvi. 1889), p. 71, pi. xix. 
fig. 1. — Huron Shale (Upper Devonian); Franklin Co., 
Ohio. 

An undetermined species, as large as the type, also seems to be 
indicated by some robust, sigmoidally curved teeth from the Devo- 
nian of Gerolstein, Eifel, Germany, preserved in the Museum of 
Comparative Zoology, Cambridge, Mass., U.S.A. 



394 CR0SS0PTER5TGII. 



Suborder III. ACTINISTIA. 



Notochord persistent. Axonosts of each of the dorsal and anal 
fins fused into a single piece ; a series of axonosts, equal in number 
to the supporting neural and haemal spines, present in the caudal 
fin above and below, each axonost directly connected with a single 
dermal fin-ray. Axonost of pelvic fin on each side single, the right 
and left not fused together mesially. 

Of this suborder only one family, that of the Coelacanthidae, is 
at present known. 

Family CCELACANTHID^E. 

Body deeply and irregularly fusiform, with cycloidal, deeply- 
overlapping scales, more or less ornamented wibh ganoine. Branchi- 
ostegal apparatus consisting of an operculum on each side and a 
single pair of large jugular plates. Paired fins obtusely lobate. 
Two dorsal fins and a single anal; the anterior dorsal without 
baseosts, the posterior dorsal 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 fin. Air-bladder ossified. 

As in many other primitive types of fishes, the arches and spines 
of the axial skeleton in this family are only superficially ossified, 
thus appearing, in the fossilized state, as if originally hollow. Such 
an appearance suggested the name of Coelacanthidae to Agassiz, 
who used the term in a wide and somewhat indefinite sense. The 
first scientific definition of the family was given by Huxley in 
1861 and 1866. 

The most satisfactory information concerning the osteology of 
the Coelacanthidae is afforded by remains from the Chalk of Eng- 
land and the Lithographic Stone of Bavaria. Macropoma, from 
the Chalk, is described in detail by Huxley \ chiefly from specimens 
recorded below ; while the genera of the Lithographic Stone are 
elucidated by Reis in a recently published memoir 2 . Undina gulo, 
from the English Lias, is also often well preserved, and a restora- 
tion of the skeleton is given in fig. 53, p. 412. 

1 T. H. Huxley, " Illustrations of the Structure of the Crossopterygian 
Ganoids " (Mem. Geol. Surv. dec. xii. 1866). 

2 O. M. Reis, " Die Ccelacanthinen, mit besonderer Beriicksichtigung der im 
Weissen Jura Bayerns vorkommenden Gattungen" (Palaeontographica, vol. 
xxxv. 1888). 



CXELACANTHID^:. 



395 



The cranium of Macropoma, which may be regarded as a 
typical Ccelacanth, is well ossified and provided with robust mem- 
brane-bones. The roof of the skull is divisible " into two moieties, 
an anterior or frontal, and a posterior or occipito-parietal, which 
meet at an obtuse angle, the occipito-parietal moiety being nearly 
parallel with the base of the skull, while the frontal slopes obliquely 
forwards and downwards to the snout ; the occipito-parietal portion 
is slightly convex from before backwards, and more so from side to 
side ; while the frontal portion, though convex from side to side, is 
slightly concave from before backwaids." The occipito-parietal 
region comprises a pair of large bones meeting in the middle line, 
evidently to be regarded as parietals, flanked postero-externally by 
a pair of triangular bones, which appear to represent the squamosal 
fused with the post-temporal. The frontals are long and narrow, 
separated by a suture at the median line, and flanked on each outer 
margin by a single series of small quadrate membrane-bones, which 
have been named parafrontals. The chondrocranium itself is exten- 
sively ossified, but there is no interorbital septum ; and the base is 
formed by a long slender parasphenoid bone, which exhibits a spatu- 
late expansion anteriorly. 

The hyomandibular and pterygo-quadrate arcade are fused into 
a continuous triangular, lamelliform bone on each side, articulating 
with the hinder portion of the cranium above, and provided postero- 
inferiorly with a ginglymoid condyle for the articulation of the 
mandible below. The bone terminates in an attenuated angle in 
front, and its superior portion is inclined inwards, so that the inner 
surface forms the roof of the mouth ; this surface is finely granu- 
lated and its lower border exhibits weJl-developed teeth, while the 
outer surface is smooth. In front of the pterygo-quadrates, a pair 
of thin small palatine bones, with more or less formidable teeth, 
occurs ; and immediately in advance of these is a large azygous 
robust element, beaiing a cluster of strong teeth, probably to be 
regarded as the coalesced vomers. The actual termination of the 
snout is not definitely known in Macropoma • but in the Upper 
Jurassic genera it is stated by von Zittel l to consist of a blunt 
rostrum, showing no sutures, and much resembling that of some 
of the early Dipnoi. The eye is surrounded by a ring of small, 
delicate sclerotic plates, suggestive of those of certain Palaeozoic 
Amphibia. There are two large quadrate cheek-plates, one above the 

1 Handb. Palaeont. vol. iii. p. 173. This description suggests that the 
undetermined snout from the Sussex Chalk noticed and figured by the present 
writer in Proc. Geol. Assoc, vol. xi. (1889), p. 31, pi. i, fig. 6, may pertain to 
Macropoma. 



300 CROSSOPTERTGTT. 

other, covering the space behind the eye, and immediately below 
these is another ornamented membrane-bone, triangular in shape, 
elongated antero-posteriorly, and named post-maxillary by Huxley. 
A single narrow, arched, suborbital element extends from the post- 
orbital s to the edge of the anterior portion of the cranial roof ; and 
below this are indications of a long and narrow dentigerous maxilla, 
ornamented on its external aspect. The latter bone is termed pala- 
tine by von Zittel and Reis, but, as already perceived by Huxley, 
it has much more the appearance of an external element. The 
premaxilla is not certainly known. The greater portion of each 
mandibular ramus is formed by a long, narrow articulo-angular 
element, ornamented externally, having a nearly straight inferior 
margin, an arched superior margin in advance of the articulation, 
and exhibiting a short extension behind this facette. The small 
toothless dentary element meets this bone in front, reaching to the 
symphysis, and bounded below by a thin infradentary. A long, 
deep, laminar splenial bone, tapering in front, but with a straight 
dentigerous border in the greater part of its length, is apposed to 
the dentary and articulo-angular on their inner face ; and this forms 
the inner wall of a vacuity existing between the upper portion of 
the two outer elements. 

The robust ceratohyal on each side is connected with the hyo- 
mandibular by an elongated bone, with expanded extremities, 
which may be regarded as the stylo-hyal. This element is termed 
metapterygoid by Reis, and is supposed by that author to have 
supported a " praeclavicular " fin. The latter determination, how- 
ever, is founded upon two distorted fishes from the Bavarian Litho- 
graphic Stone, in the Munich Museum, which exhibit accidentally 
displaced fragments of the pectoral fin-rays at the postero-inferior 
angle of the head. 

The branchial arches are four or five in number on each side, deli- 
cately and deeply channelled on the hinder aspect as in Polypterus 
and modern bony fishes. So far as has been definitely observed, 
each arch consists of a single pair of much arcuated elements, in 
some genera with sparse appended bony denticles ; and a single 
large copula, with spatulate hinder extremity, unites all the lower 
extremities of the arches in the median line. 

The notochord must have been persistent, and the present writer 
has not observed any satisfactory indications of ossified elements in 
the notochordal sheath. According to Reis \ however, hypocentra 
are distinguishable in the so-called Ccelacanthus Jiassice. The 

1 Op. cit. p. 70, pi. iv. figs. 15, 16, 19. 



(XELACASTTHIDiE. 397 

neural arches and spines are long and slender, the two halves of 
each arch being firmly united with their appended spine. In the 
abdominal region, the hamial arches are delicate and rudimentary, 
but in the caudal region they correspond in development to the 
opposed neural elements. So far as known, these ossifications 
extend only to the termination of the principal caudal fin, the 
small supplementary caudal never displaying hard endoskeletal 
structures. 

The paired fins are always well-developed and obtusely lobate. 
The membrane-bones of the pectoral arch, though slender, are con- 
spicuous, and seem to have been completely covered by the skin. The 
long, gently curved clavicle often exhibits a robust post-clavicular 
process, and articulates above with a small supraclavicle ; while a 
long, slender infraclavicle overlaps its lower spatulate extremity. 
The last-mentioned element curves sharply forwards and inwards, 
terminating in a triangular expansion, where it meets its fellow of 
the opposite side in a median suture (see PI. XIV. fig. 3, i. cl.). The 
pelvic fins are supported by a pair of elongated, slender basipterygia 
with an inwardly directed process at the distal end, by which they 
are loosely apposed in the median line. 

• Of the two dorsal fins, the anterior is destitute of baseosts, the 
stout dermal rays directly articulating with the nearly straight 
upper border of the single laminar axonost. This fin therefore 
exhibits no lobation. The posterior dorsal fin and the opposed anal 
resemble the paired fins in being distinctly lobate. As in the paired 
fins, the baseosts must have been too slightly ossified for preservation, 
the lobe being always a vacant space in the fossils ; but there is a single 
forked axonost to each fin, this almost invariably exhibiting a high 
degree of ossification. The principal caudal fin is symmetrical, and 
supported by a single series of long slender bones above and below, 
equalling in number, and directly apposed to, the blunt distal 
extremities of the neural and haemal spines of the axial skeleton. 
A single stout dermal ray is connected with each of these elements 
by a simple overlapping articulation ; and a sparse series of very 
small rays fringing the supplementary caudal lobe, when present, is 
probably in direct contact with the unossified spines of the axial 
skeleton itself. None of the fin -rays are bifurcated, but all are 
more or less articulated distally. 

A conspicuous feature in the abdominal region of all Ccelacanths 
is the ossified air-bladder, which attains a large size, and sometimes 
exhibits a single anterior aperture by which its internal cavity 
communicated with the oesophagus. Its walls are formed of three 
paired longitudinal series of large, imbricating, bony laminae, each 



398 CR0SS0PTEKTG1I. 

composed of a number of superposed lamellae ; and the inner face is 
described by von Zittel as exhibiting large reticulating rugae, 
suggestive of the network made known by Owen in the lung-like 
air-bladder of the recent Protopterus. 

In all known genera, imbricating scales are present over the 
whole of the trunk, and the superficial layer of ganoine is not con- 
tinuous, but arranged in tubercles and striae. The lateral line is 
either inconspicuous or leaves no impression upon the scales. 

Though ranging from the Lower Carboniferous to the Upper 
Chalk, the skeletal characters of the Ccelacanthidae exhibit little 
variation ; and it is difficult to recognize differences sufficiently 
marked to be regarded as justifying the subdivision of the family 
into a series of genera. The arrangement and proportions of the 
fins are almost constant, the supplementary caudal being apparently 
the only variable element. The other more important features 
available for generic diagnoses are (i) the ornamentation or other- 
wise of the head, opercular apparatus, and scales ; (ii) the presence 
or absence of denticles upon the fin-rays ; and (iii) the more or less 
jointed or non-jointed character of the rays themselves. One or two 
genera (Libys and Heptanema) are also apparently characterized by 
the relatively great development of the mucus-canals upon the head. 

With regard to specific characters, imperfections in the pre- 
servation of the specimens render their precise determination often 
impossible. The number of rays in the median fins, especially the 
principal caudal, seems to vary in different species of the same 
genus ; though this character can only be noted when there appears 
to have been no displacement of parts in the fossil. Minor vari- 
ations in scale-ornament, and the ornamentation and proportions 
of the head and opercular bones, may also be cited as specific 
differences. 

Synopsis of Genera. 

I. No denticles or tuberculations on fin-rays. 
Superficial ornament of more or less discon- 
tinuous ridges ; supplementary caudal fin 

prominent Ccdacanthv.s (p. 399). 

II. Denticles or tuberculations on preaxial rays of 

anterior dorsal and caudal fins. 
A. Fin-rays with numerous close articulations ; 
supplementary caudal fin prominent. 
No parafrontal pits; superficial ornament 
mostly tubercular ; fin-rays very robust, 
articulated nearly to the base ; supple- 
mentary caudal stout Graphiurus (p. 409) 



CCELACANTHID.E. 399 

Superficial ornament of irregular striae ; fin- 
rays articulated in distal half; supple- 
mentary caudal much elongated Diplurus (p. 409). 

No parafrontal pits ; superficial ornament of 
irregular striae and tubercles; fin-rays 
articulated for a long extent distally ; 
supplementary caudal stout Undina (p. 409). 

Parafrontal and suborbital pits for enlarged 
mucus-follicles ; otherwise resembling 
Undina Libijs (p. 413). 

No parafrontal pits ; superficial ornament of 
sparse tubercles, spinous on the scales ; 

supplementary caudal stout. Coccoderma (p. 415). 

B. Fin-rays long and slender, articulated only 
for a short space distally ; supplementary 
caudal fin apparently rudimentary or 
absent. 

Parafrontals with pits for enlarged mucus- 
follicles ; scale-ornament consisting of a 
prominent median spinous tubercle, with 
smaller tubercles above and below .... Heptanema (p. 415). 

No parafrontal pits ; superficial ornament of 

spinous tubercles Macropoma (p. 416). 

Of the genera thus enumerated, those named Graphiurus, 
Diplurus, and Coccoderma seem least entitled to distinction, being 
separated from Undina (so far as known) only by characters of slight 
importance. 



Genus CCELACANTHUS, Agassiz. 

[Poiss. Foss., Feuill. 1836, p. 83, and vol. ii. pt. ii. 1844, p. 170.] 

Syn. Hoplopygus, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. 1844, p. 178. 
Conchiopsis, E. D. Cope, Proc. Acad. Nat. Sci. Philad. 1873, 

p. 341. 
Hhabdoderma, 0. M. Reis, Palaeontographica, vol. xxxv. 1888, 

p. 71. 

The typical genus. Teeth absent on the margin of the jaws, but 
a few hollow, conical teeth within. Supplementary caudal fin 
prominent ; the rays of all the fins long and slender, unjointed for 
a considerable length proximally, closely articulated, but without 
expansion, distally ; denticles absent upon all the rays. External 
bones and scales superficially ornamented with series of tubercles 
or fine ridges of ganoine. 



400 CROSSOPTEKIGll. 

Ccelacanthus granulatus, Agassiz. 

1829. " Fossil Fish," A. Sedgwick, Trans. Geol. Soc. [2] vol. iii. p. 118, 

pi. xi. 
1339. Ccelacanthus granulatus y L. Agassiz, op. cit. vol. ii. pi. lxii. 

(name and Hg. only). 
1842. Ccelacanthus hassice, G. von Miinster, Beitr. Petrefakt. v. p. 49. 

[Head and abdominal region ; British Museum, and Palaeontological 

Museum, Munich]. 
1844. Ccelacanthus granulosus, L. Agassiz, op. cit. vol. ii. pt. ii. p. 172. 
1850. Ccelacanthus granulatus, Sir P. Egerton, in King's Permian 

Foss. (Pal. Soc), p. 235, pi. xxviii*. 
1850. Ccelacanthus caudalis, Sir P. Egerton, ibid. p. 236, pi. xxviii. 

fig. 2. [Immature fish ; British Museum.] 
1861. Pygopterus humboldti, H. B. Geinitz (errore), Dyas, pi. viii. 

figs. 1-3. 
1866. Ccelacanthus caudalis, T. H. Huxley, Fig.=. & Descrips. Brit. 

Organic Remains (Mem. Geol. Surv.), dec. xii. pp. 14, 21, pi. v. 

fig. 5. 
1869. Ccelacanthus macrocephalus, R. von Willemoes-Suhm, Palaeon- 

tographica, vol. xvii. p. 74, pi. xi. fig. 2. [Head and abdominal 

region ; Palseontological Museum, Munich.] 
1869. Ccelacanthus hassice, R. von Willemoes-Suhm, ibid. p. 76, pi. x. 

fig. 1, pi. xi. fig. 1. 
1888. Ccelacanthus macrocephalus, 0. M. Reis, Palaeontographica, vol. 

xxxv. p. 68. 
1888. Ccelacanthus hassice, 0. M. Reis, ibid. p. 69, pi. iii. fig. 22, pi. iv. 

figs. 7, 12, 15, 16, 19. 
1890. Ccelacanthus granulosus, Woodward & Sherborn, Cat. Brit. 

Foss. Vertebrata, pp. 39, 40. 

Type. Caudal region ; British Museum. 

The type species, attaining a length of about 0*45. Trunk 
robust, but elongated. Dorsal fins of relatively large size, the 
first consisting of about 10-12 rays and situated slightly in advance 
of the pelvic pair, the second consisting of more numerous slender 
rays ; principal caudal fin comprising about 20 stout rays above and 
below. Scales ornamented with coarse, antero-posteriorly elongated 
tubercles, often arranged in series. 

Form. Sf Loc. Upper Permian (Marl Slate) ; Durham. Upper 
Permian (Kupferschiefer) : Germany. 

P. 3338. Type specimen figured by Agassiz, torn. cit. pi. lxii. fig. 1 ; 
Marl Slate, Ferry Hill. EnnisTcillen Coll, 

P. 3339-40. Three imperfect specimens showing portions of the 
head and anterior abdominal region ; two from Fulwell 
Hill, the third from Midderidge. The bones are much 



CCELACANTHID.K. 401 

crushed and broken, and there are remains of widely 
spaced, hollow, conical teeth on an elongated slender 
element in each of the two specimens entered under the 
first number. Enniskillen Coll. 

P. 554. Caudal region figured in King's Permian Foss. pi. xxviii.* ; 
Ferry Hill. Egerton Coll. 

P. 3339 a. Imperfect caudal region of small individual ; Fulwell 
Hill. Enniskillen Coll. 

P. 555, P. 3335. Immature individual, in counterpart, labelled C. 
granulatus by Agassiz, but described by Egerton as the 
type of a distinct species, C. cauddlis ; Ferry Hill. 

Egerton 6f Enniskillen Colls. 

38586. Counterpart of type specimen of C. hassice, Munster ; 
Eiechelsdorf , Hesse. The fossil in the Miinster Collection, 
Munich, is described and figured by Willemoes-Suhm in 
the Palseontographica, vol. xvii. p. 77, pi. x. fig. 1. 
Though not recognized by Munster, some of the character- 
istic granulated scales are distinctly exhibited. 

Purchased, 1864. 

40372, 43429. Imperfect head and abdominal region, in counterpart, 
showing the characteristic squamation and portions of the 
paired and first dorsal fins ; the first- mentioned side of 
the fossil also exhibiting a few hollow, conical teeth ; 
lliechelsdorf. Purchased, 1865, and 

Presented hy Kenneth Murchison, Esq., 1872. 

43427, P. 3342. Remains of head and abdominal region of a large 
individual, in counterpart; Biechelsdorf. The clavicles 
are well displayed. 

Presented by Kenneth Murchison, Esq., 1872, 
Sf Enniskillen Coll. 

43426. Portion of abdominal and caudal regions, displaying the 
dorsal and anal fins, and portions of the principal caudal 
and pelvic pair ; Eiechelsdorf. 

Presented by Kenneth Murchison, Esq., 1872. 

P. 753. Imperfect remains of abdominal and caudal regions ; 
lliechelsdorf. Egerton Coll. 

P. 3342 a, "b. Fragments of caudal region, the second in counter- 
part; Eiechelsdorf. 

Egerton Sf Enniskillen Colls. 

PART II. 2 D 



402 CROSSOPTERYGII. 



Ccela can thus tingleyensis, Davis. 

1884. Codacanthus tingleyensis, J. W. Davis, Trans. Linn. Soc. ser. 2, 

(Zoology), vol. ii. p. 427, pis. xlvi.-xlix. 
1888. Rhabdoderma tinyleyense, 0. M. Reis, Palaeontogr. vol. xxxv. p. 72. 

Type. Various portions of fishes ; collection of J. W. Davis, Esq. 

A large species, about equal to the typical C. granulatus in size. 
Trunk robust, but elongated. Dorsal fins of relatively large size, 
the first consisting of very stout rays and situated slightly in advance 
of the pelvic pair, the second consisting of more numerous slender 
rays ; principal caudal fin comprising 18-20 stout rays above and 
below. Jugular plates ornamented with fine, concentric, and 
vermiculating ridges ; operculum and some of the cranial roof- 
bones with the ornament partly consisting of series of tubercu- 
lations ; scales ornamented with fine antero-posterior ridges, some- 
times irregularly constricted at intervals, sometimes divided into 
series of elongated tubercles. 

Form, fy Loc. Middle Coal-Measures : Yorkshire. 

The following specimens were presented by the Earl of Ennis- 
killen, 1882 :— 

P. 1187. Remains of a small head, opercular apparatus, clavicle, 
and a few scales, labelled by J. W. Davis ; Tingley. 

P. 1187 a-C. Three specimens, similarly labelled, the first and 
second displaying remains of the head and abdominal 
region, the third exhibiting the principal caudal fin ; 
Tingley. 

P. 1188. Well-preserved large scales, probably of this species ; 
Tingley. 

The original of the following specimen is not yet clearly distin- 
guished from C. tingleyensis : — 

42062. Plaster cast of caudal region of a large fish, named C. 
jphillipsi, L. Agassiz (Poiss. Eoss. vol. ii. p f . ii. 1844, 
p. 173), and subsequently described by J. W. Davis, Geol. 
Mag. [3] vol. vii. (1890), p. 159 ; Lower Coal-Measures, 
Halifax, Yorkshire. The original specimen is preserved 
in the Halifax Museum. 

Presented by Rev. J. B. Reade, 1870. 



CIELACA.NT1L1D-K. 



403 



Ccelacanthus elegans, Newberry. 
[Plate XIV. fig. 2.] 

1844. Ccelacanthus lepturus, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. 

p. 173 (undefined). 
1844. Hoplopygus binneyi, L. Agassiz, ibid. p. 178 (undefined). [E. W. 

Binney Collection.] 
1856. Ccelacanthus elegans, J. S. Newberry, Proc. Acad. Nat. Sci. 

Philad. vol. viii. p. 98. 
1866. Codacanthus lepturus, T. II. Huxley, Figs. & Descrips. Brit. 

Organic Remains (Mem. Geol. Surv.), dec. xii. p. 16, pi. ii. figs. 

1-4, pi. iii. figs. 1-3, pi. iv. figs. 1-6. [Museum of Practical 

Geology.] 
1866. Codacanthus elegans, T. II. Huxley, ibid. p. 20, pi. v. tigs. 1-4. 

1872. Codacanthus lepturus, A. Hancock & T. Atthey, Ann. Mag. Nat. 
Hist. [4] vol. ix. p. 256, pi. xvii. fig. 4 ; also Nat. Hist. Trans. 
North urn b. & Durham, vol. iv. p. 416, pi. xv. fig. 4. 

1873. Conchiopsis jiliferus and C. anguliferus, E. D. Cope, Proc. Acad. 
Nat. Sci. Philad. p. 342. [Imperfect fishes ; Columbia College, 
New York.] 

1873. Coslacanthus elegans, J. S. Newberry, Proc. Acad. Nat. Sci. Philad. 
p. 425, and Rep. Geol. Surv. Ohio, vol. i. pt, ii. p. 339, pi. xl. fig. 1. 

1875. Codacanthus lepturus, J. \Yard, [Proc] N. Staffs. Nat. Field Club, 
p. 242. 

1876. Coslacanthus lepturus, J. "W. Davis, Quart. Journ. Geol. Soc. vol. 
xxxii. p. 339. 

1888. Bhabdcderma lepturus and R. elegans, 0. M. Reis, Paheontogr. 
vol. xxxv. p. 5. 

1889. Ccelacanthus elegans, J. S. Newberry, Palaeoz. Fishes N. America 
(Mon. U. S. Geol. Surv. no. xvi.), p. 213. 

1890. Ccelacanthus lepturus, J. Ward, Trans. N. Staffs. Inst. Mining 
Engin. vol. x. p. 168, pi. v. figs. 1, 3. 

1890. Ccelacanthus lepturus, R. H. Traquair, Proc. Roy. Soc. Edinb. 
vol. xvii. p. 390. 

Type. Imperfect fishes ; Columbia College, New York. 

A species usually attaining only a small size, but sometimes 
probably having a total length of not less than 0*45. Body slender 
and elongated ; head with opercular apparatus occupying about one- 
fifth of the total length. Dorsal fins of relatively large size, the 
first consisting of very stout rays and situated slightly in advance 
of the pelvic pair, the second consisting of more numerous slender 
rays ; principal caudal fin comprising 12-14 stout rays above and 
below. Jugular plates tapering in front, three to three and a half 
times as long as broad, ornamented with fine vermiculating striae, 
in part concentric ; operculum about one and a half times as deep 
as broad, irregularly marked with short, fine, vermiculating striae, 

2d2 



404 CROSSOPTERYGII. 

more or less concentric with the three margins. Cranial roof-bones 
in part ornamented with series of tuberculations. Scales pointed, 
very finely striated, the striae directed antero-posteriorly and con- 
verging behind, more or less irregular, often divided into elon- 
gated tubercles in the hinder portion. 

This is the type species of Hoplopygus, Conchiopsis, and Rhab- 
doderma. 

Form. Sf Loc. Coal-Measures : Ohio, England, and Scotland. 
Culm-Measures : North Devonshire. 

P. 579-81. Three specimens described and figured by Huxley, op. 
cit. p. 20, pi. v. figs. 1-4 ; Linton, Ohio. Egerton Coll. 

P. 746. Typical specimen, wanting the pectoral fins, the second 
dorsal, and the terminal caudal ; Linton. Egerton Coll. 

P. 3334. Imperfectly preserved fish, wanting the pectoral and 
terminal caudal fins ; Linton. EnnisTcillen Coll. 

P. 3332. Imperfect caudal region, showing the terminal fin, labelled 
Ccelacanihus lepturus by Agassiz ; Leeds. 

Enniskillen Coll. 

36477. Remains of fish displaying the dorsal fins and the principal 
caudal ; Longton, K". Staffordshire. Purchased, 1862. 

P. 748. Remains of trunk showing portions of the air-bladder; 
Deep Mine, Longton. Egerton Coll. 

P. 3330-31. Two imperfect fishes ; Knowles Ironstone Shale, Ten- 
ton, and Deep Mine, Longton. EnnisTcillen Coll. 

P. 5177. Small fish, with well-preserved scales; Longton. 

Purchased, 1885. 

42382. Imperfect fish ; Gubbin Ironstone, Tipton, S. Staffordshire. 

Purchased, 1870. 

40393. Smaller specimen, in counterpart, wanting head ; Tipton. 

Purchased, 1866. 

30572. Fish with portions of well-preserved fins ; Dalemoor-Eake 
Ironstone, Stanton-by-Dale, Derbyshire. 

Purchased, 1856. 

48055. More imperfectly preserved specimen, in counterpart, dis- 
playing zne principal caudal fin; Dalemoor-Eake Iron- 
stone, Stanton-by-Dale. 

Presented by Moses Rigley, Esq., 1877. 



CXELACANTHID^:. 405 

37956. Crushed specimen showing part of the terminal caudal fin ; 
Airdrie, Lanarkshire. Purchased, 1863. 

21464. Small individual in counterpart ; Carluke. 

Purchased, 1847. 

41197. Fragmentary remains of small individual ; Low Main Seam, 

Newsham, Newcastle-upon-Tyne. Purchased, 1868. 

21952. Detached head, much crushed, inferior aspect; Carluke. 

Purchased, 1847. 

P. 751. Pterygo-suspensorium; Lowmoor, Yorkshire. Egerton Coll. 

P. 3333. Pterygo-suspensorium ; Lowmoor. Ennislcillen Coll. 

The following specimens are regarded as pertaining to an un- 
described species by T. M. Hall, Geol. Mag. [2] vol. iii. (1877), 
p. 410. The only differences from the typical C. elegans, however, 
seem to be due to the circumstances of fossilization : — 

P. 5379, P. 6286. Pine specimen, in counterpart, discovered by W. 
Porter, Esq., in a bed of nodules, of the Culm-Measures, 
near Instow. One side of the split nodule is shown, of 
the natural size, in PI. XIV. fig. 1 2, some bones of the head 
and opercular apparatus being introduced from the opposite 
side. The pectoral fins are almost entirely wanting, and the 
ventral portion of the abdominal region is partly displaced 
by crushing. The head is also imperfectly preserved ; 
and an irregular ferruginous mass appears to indicate the 
position and extent of the air-bladder. One of the jugular 
plates (ju.) is displaced beneath the articulo-angular 
bone (d.) and exhibits a remarkably acuminate anterior 
extremity. There is evidence of two or three ornamented 
cheek-plates (a?.) behind the eye ; and the impression of a 
narrow bone forms the lower boundary of the orbit. The 
triangular operculum (op.), with its fine ornamentation, 
seems to be completely preserved as an impression ; and 
there are traces behind this of the pectoral arch. The 
characters of the fins and squamation, so far as recog- 
nizable, are noted in the specific diagnosis. The scales 
seem to occur merely as impressions, and those of the 
flank (fig. 2 a) thus appear to be marked with extremely 
delicate convergent lines (the infilling of the fissures 
between the original ridged ornament), which meet in a 
posterior reticulation. 
Purchased, 1886, and presented by W. Porter, Esq., 1890. 



406 CROSSOPTRRTGII. 

P. 6101. Group of scales and fragments of head-bones ; Instow. 

Purchased, 1886. 



Ccelacanthus robustus, Newberry. 

1856. Ccelacanthus robustus, J. S. Newberry, Proc. Acad. Nat. Sci. 

Pliilad. vol. viii. p. 98. 
1873. Ccelacanthus robustus, J. S. Newberry, Rep. Geol. Surv. Ohio, 

vol. i. pt. ii. p. 341, pi. xl. fig. 2. 
1888. Rhabdoderma robustum, 0. M. Reis, Pabeontogr. vol. xxxv. p. 5. 

Type. Imperfect fishes ; Columbia College, New York. 

A species of moderate size, not very satisfactorily distinguished 
from 0. elegans. Jugular plates rapidly tapering and acuminate in 
front, three and a half times as long as broad ; operculum some- 
what less than one and a half times as deep as broad ; both orna- 
mented with fine, concentric, and vermiculating stria?. Cranial 
roof-bones tuberculated. Scales as in C. elegans. 

Form. 6f Loc. Coal-Pleasures : Ohio. 

P. 747. Two examples of the operculum and remains of a head 
showing portions of the jugular plates, labelled by Dr. 
Newberry ; Linton, Ohio. Egerton Coll. 



Ccelacanthus elongatus, Huxley. 

1866. Ccelacanthus elongatus, T. H. Huxley, Pigs. & Descrips. Brit. 
Organic Remains (Mem. Geol. Surv.), dec. xii. p. 23, pi. v. figs. 6, 7. 

Type. Imperfect fishes : Geological Survey of Ireland. 

An imperfectly known species, with well-developed fins ; ap- 
parently distinguished from other species hitherto described in the 
narrow elongated form of the head and trunk. 

Form. Sf Loc. Coal-Measures ; Ballyhedy near Ballinhassig, Co. 
Cork. 

Not represented in the Collection. 

According to J. S. Newberry (Rep. Geol. Surv. Ohio, vol. i. pt. ii. 
1873, p. 340), C. elongatus is probably represented in America by 
a species from the Coal-Measures of Linton, Ohio, named C. omatus, 
J. S. Newberry, Proc. Acad. Nat. Sci. Philad. vol. viii. (1856), p. 98, 
and Palaeoz. Fishes N. America (Mon. U. S. Geol. Surv. no. xvi. 
1889), p. 227. By 0. M. Reis (Pakeontogr. vol. xxxv. 1888, p. 5) 
the former is retained in the genus Coelacanflius, while the latter is 
removed to the so-called Rhabdoderma. 



CCELACANTHIDJE. 407 

Ccelacanthus huxleyi, Traquair. 

[Plate XIV. fig. 1.] 

1881. Ccelacanthus huxleyi, R. H. Traquair, Trans. Roy. Soc. Edinb. 

vol. xxx. p. 20, pi. i. figs. 1-4. 
1888. Rhabdoderma huxleyi, O. M. Reis, Palaeontogr. vol. xxxv. p. 5. 

Type. Imperfect fishes ; Geological Survey of Scotland. 

A small species, attaining a maximum length of about 0-18. 
Trunk robust but elongated ; head with opercular apparatus occu- 
pying about one fourth of the total length. Dorsal fins of relatively 
large size, the first consisting of very stout rays and situated slightly 
in advance of the pelvic pair, the second consisting of more 
numerous slender rays ; principal caudal fin comprising about 14 
stout rays above and below. Jugular plates four times as long as 
broad, ornamented with few, delicate, concentric striae ; opercular 
bones three-quarters as broad as deep, smooth or feebly striated ; 
head-bones in part marked with few coarse striae, sometimes divided 
into elongated tubercles ; scales externally ornamented with very 
delicate, widely spaced, posteriorly converging striae. 

Form. <$f Loc. Calciferous Sandstones (Cement-stone Group) : 
Eskdale, Dumfriesshire. 

P. 4079 a. Large individual, in counterpart, wanting terminal 
caudal fin, probably originally about 0*18 in total length. 
A jugular plate, the opercular bones, and calvicle. as 
preserved, exhibit none but the faintest external ornamen- 
tation ; but one of the cheek-plates is externally marked 
with a few coarse concentric striae and irregular tubercles. 

Purchased, 1883. 

P. 4079 b. Specimen about 0-105 in length, with imperfect head 
and fins. Purchased, 1883. 

P. 4080 a. Small individual showing the terminal caudal fin, 
represented, of the natural size, in PI. XIY. fig. 1, the 
scales and jugular plate being enlarged three times in 
figs. 1 a, 1 b. Purchased, 1883. 

P. 4080 b. Similar specimen, displaying the dorsal fins. 

Purchased, 1883. 

P. 4079-80. Six small fishes, some showing smooth opercular bones. 

Purchased, 1883. 

P. 5983. Small individual. Purchased, 1889. 



403 CROSSOPTERYGII. 

Coelacanthus gracilis, Agassiz. 
1844. Coelacanthus gracilis, L. Agassiz, Pois. Foss. vol. ii. pt. ii. p. 173. 

Type. Portion of caudal region ; British Museum. 

An imperfecta definable species, known only by the type spe- 
cimen mentioned below. Body apparently elongated and slender ; 
principal caudal fin comprising about 14 widely-spaced rays above 
and below ; scales in part coarsely striated, in part tuberculated. 

Form. Sf Loc. Unknown (? Muschelkalk, Germany). 

P. 3341. Type specimen, 0*11 in length, comprising the principal 
caudal fin and a portion of the caudal region in advance of 
this. The body is very narrow, and the caudal fin-rays 
are relatively long, showing wide articulations distally. 
Several portions of scales occur, and there are apparently 
traces of fossilized muscle. Enniskillen Coll, 

The following specimens are also probably referable to a species of 
Coelacanthus : — 

P. 3346-51. Jugular plate and five other external bones, orna- 
mented with irregular striae, ascribed to Coelacanthus by 
J". W. Davis, Trans. Eoy. Dublin Soc. [2] vol. i. p. 524, 
pi. lxiii. figs. 7-12 ; Lower Carboniferous Limestone, 
Armagh. EnnisJcillen Coll. 

The undefined species, Coelacanthus minor, Agassiz (Poiss. Foss. 
vol. ii. pt. ii. 1844, p. 173), from the Muschelkalk of Luneville, may 
pertain either to this genus or to Heptanema. 

The genus Peplorhina, E. D. Cope (Proc. Acad. JS"at. Sci. Philad. 
1873, pp. 343, 418), is placed near to Coelacanthus (Conchiopsis) by 
its founder, but regarded as Amphibian by J. S. Newberry (ibid. 
p. 426). The type species, from the Coal-Measures of Linton, Ohio, 
is named P. anthracina, E. D. Cope (ibid. p. 343, and Rep. Geol. 
Surv. Ohio, vol. ii. pt. ii. 1875, p. 410, pi. xxxv. fig. 6, pi. xli. figs. 
4, 5), and also includes Conchiopsis exanthematicus, E. D. Cope 
(Proc. Acad. Nat. Sci. Philad. 1873, p. 342). The type specimens 
are in the Museum of Columbia College, New York. A diamond- 
shaped dentigerous plate, from the Permian of East Illinois, has 
also been assigned to the genus under the name of P. arctata, E. D. 
Cope (Proc. Amer. Phil. Soc. vol. xvii. 1878, p. 54). 



CCELACANTHID^l. 409 

Genus GRAPHIURUS, Kner. 

[Sitzungsb. k. k. Akad. Wiss. Wien, math.-naturw. CI. vol. liii. 
pt, i. 1866, p. 155.] 

Supplementary caudal fin prominent ; the rays of all the fins 
broad, expanded, distally pointed, and closely articulated almost to 
the base ; preaxial rays of the first dorsal and caudal fins tuber- 
culated. Scales and head-bones tuberculated. 

So far as known, this genus comprises only one small species, 
of which there are no specimens in the Collection : — 

Graphiumis callopterus, R. Kner, Sitzungsb. k. k. Akad. Wiss. 
Wien, math.-naturw. CI. vol. liii. pt. i. (1866), p. 155, 
pi. i. ; 0. M. Eeis, Palseontographica, vol. xxxv. (1888), 
p. 67, pi. v. figs. 9, 10. — Upper Keuper ; Eaibl, Carinthia. 
[Imperial Geological Survey, Vienna.] 

Genus DIPLURUS, Newberry. 

[Ann. New York Acad. Sci. vol. i. 1878, p. 127.] 

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. 

So far as known, this genus comprises only one large species, of 
which there are no specimens in the Collection : — 

Diphmu longicaudatus, J. S. Newberry, loc. cit. p. 127, and Foss. 
Fishes Trias, N. Jersey and Connecticut (Mon. U. S. 
Geol. Surv. no. xiv. 1888), p. 74, pi. xx. — Trias ; New 
Jersey and Connecticut, U. S. A. [Columbia College, 
New York.] 

Genus UNDINA, Minister. 

[Neues Jahrb. 1834, p. 539.] 

Syn. Holophagus, Sir P. Egerton, Figs. & Descrips. Brit. Organic 
Remains, dec. x. (Mem. Geol. Surv. 1861), p. 19. 

Teeth absent on the margin of the jaws, but a few hollow, conical 
teeth within. Supplementary caudal fin prominent ; the rays of 
all the fins broad and robust, often expanded, and closely articulated 
in the distal portion ; small, upwardly-pointing denticles on the 
preaxial rays of the first dorsal and caudal fins. External bones 
and scales superficially ornamented with tubercles or fine interrupted 
ridges of ganoine : parafrontal and circumorbital bones plate-like, 
without superficial excavations. 



410 



CROSSOPTERYGII. 



Undina penicillata, Miinster. 

1834. Undina penicillata, G. von Miinster, Neues Jahrb. p. 539. 
1842. Ccelacanthus striolaris, G. von Miinster, Neues Jahrb. p. 40. 

[Palaeontological Museum, Munich.] 
1842. Ccelacanthus holder i, G. von Miinster, ibid. p. 40. [Ibid.] 
1842. Ccelacanthus striolaris, G. von Miinster, Beitr. Petrefakt. pt. v. 

p. 57, pi. ii. figs. 1, 3, 5, 6, 8-10, 12, 14, 16. 
1842. Ccelacanthus hohleri, G. von Miinster, ibid. p. 59, pi. ii. figs. 2, 4, 

7, 11, 13, 15, 17. 
1844. Undina striolatus and U. hohleri, L. Agassiz, Poiss. Foss. vol. ii. 

pt. ii. p. 171. 
18G3. Undina penicillata, A. Wagner, Abh. math.-phys. CI. k.-bay. 

Akad. Wiss. vol. ix. p. 696. 
1869. Ccelacanthus penicillatus, R. von Willemoes-Suhm, Palaeonto- 

graphica, vol. xvii. p. 80, pi. x. figs. 2, 3, pi. xi. fig. 3. 
1871. Ccelacanthus harlemensis, T. C. Winkler, Archives Mus. Teyler, 

vol.'iii. p. 101, pi. iv. [Teyler Museum, Haarlem.] 
1881. Ccelacanthus harlemensis, B. Vetter, Mittheil. k. mineral.-geol. 

Mus. Dresden, pt. iv. p. 13, pi. ii. fig. 4. 
1887. Undina penicillata, K. A. von Zittel, Handb. Palseont. vol. iii. 

p. 175, woodc. fig. 177. 

1887. Undina acutidens, K. A. von Zittel, ibid. p. 175, woodc. fig. 177b 
(fig. of scales only). 

1888. Undina penicillata, 0. M. Reis, Palaeontographica, vol. xxxv. 
pp. 30, 36, pi. ii. figs. 5, 6, 9, 10, pi. iv. figs. 3, 4. 

1888. Undina acutidens, O. M. Reis, ibid. pp. 10, 36, pi. i. figs. 2-6, 
8-24. [Palaeontological Museum, Munich.] 

Type. Nearly complete individual ; Palaeontological Museum, 
Munich. 

The type species, attaining a length of about 0-4. Trunk robust, 
but elongated : head and opercular apparatus occupying somewhat 
less than one quarter of the total length. Fin-rays slightly ex- 
panded in the articulated distal half ; dorsal fins well developed, the 
first consisting of about 10 relatively stout rays, the second and the 
anal each comprising at least twice that number of more slender rays ; 
principal caudal fin comprising about 18-20 stout rays above and 
below. Jugular plates four times as long as broad, covered with 
sparse elongated tubercles ; operculum, cheek-plates, and mandible 
delicately tuberculated. Scales ornamented with numerous irre- 
gularly and closely arranged, elongated tubercles. 

The occasional smooth appearance of the jugular, operculum, and 
cheek-plates of this species is doubtless owing to post-mortem 
accident before or during fossilization. The same remark probably 
applies to the varying presence or absence of the larger teeth among 
the smaller ones. 



CCELACANTHID^. 



411 



Form. Sf Loc. Lower Kimmeridgian (Lithographic Stone) : 
Bavaria. 

49143. Plaster cast of type specimen, figured by von Zittel, torn. cit. 
p. 175, woodc. f. 177 ; Zandt, near Eichstadt. 

Purchased, 1878. 

37032. Imperfectly preserved fish, in counterpart, wanting the 
terminal caudal fin ; Solenhofen. An external ornament 
of large elongated tubercles, closely arranged, is seen upon 
a bone probably pertaining to the mandible. 

Hdberlein Coll. 

P. 5543. Well-preserved specimen, 0-4 in length, wanting portions 
of the head and the terminal caudal fin ; Eichstadt. A 
few large conical teeth and some of the sclerotic plates 
are exhibited ; and below the mandible is the impression 
of a large jugular plate of which a fragment shows the 
ornament. The scales of the flanks are ornamented by 
short striae, fewer and more elongated than those upon 
the scales figured by von Zittel as U. acutidens. 

Purchased, 1888. 

It still remains doubtful whether the following supposed distinct 
species is not founded upon a young individual of U. penicillata : — 
Undina minuta, A. Wagner, Abh. math.-phys. CI. k.-bay. Akad 
Wiss. vol. ix. (1863) p. 697 ; 0. M. lieis, Palaeontogr. vol. 
xxxv. (1888), pp. 6, 30, 36, pi. i. fig. 1 : Coelacanthus 
minutus, R. von Willemoes-Suhm, Palseontogr. vol. xvii. 
(1869), p. 79, pi. xi. fig. 4 : Undina cirinensis, V. Thiolliere, 
Poiss. Foss. Bugey, pt. i. (1854), p. 10. — Lower Kimme- 
ridgian (Lithographic Stone) ; Cirin, Ain, France, and 
Bavaria. [Pakeontological Museum, Munich.] 

Undina gulo (Egerton). 

1861. Holophagus gulo, Sir P. Egerton, Figs. & Descrips. Brit. Organic 

Remains (Mem. Geol. Surv. ), dec. x. p. 19. 
1866. Holophagus gulo, T. H. Huxley, ibid. dec. xii. p. 26, pi. vi. 
1872. Holophagus gulo, T. H. Huxley, ibid. dec. xiii. no. 10, pi. x. 

Type. Fish, wanting head ; Museum of Practical Geology. 

A large species, attaining a length of about 0*7. Trunk robust ; 
head and opercular apparatus occupying one quarter of the total 
length. Dorsal fins well developed, the first consisting of about 10 
relatively stout rays, the second and the anal comprising more 



41L> 



CROSSOPTEKYGII. 



numerous and more slender rays, much expanded and closely arti- 
culated distally ; principal caudal fin consisting of about 16-18 stout 
rays above and below, much expanded and closely articulated dis- 



Fig. 53. 




Undina gulo (Egert.). — Eestored skeleton. The supraclavicle is omitted, and 
the cheek-plates are inferred to have been arranged as in other Coelacanths. 
The facial bones in advance of the orbit are unknown. 



tally. Mandibular and opercular bones and jugular plates externally 
ornamented with large, very closely arranged, rounded tubercles ; 
scales with numerous, irregularly and closely arranged, elongated 
tubercles. 

This is the type species of the so-called Holopliagus. 

Form. <$f Loc. Lower Lias : Lyme Regis, Dorsetshire. 

P. 3344. Specimen figured in Mem. Geol. Surv. dec. xiii. pi. x. 

Enniskillen Coll. 



P. 2022. Fine small specimen, 0*255 in length, wanting the pelvic 
and anal fins, and parts of the anterior dorsal and supple- 
mentary caudal. The ornament of one of the jugular 
plates is well preserved. Egerton Coll. 

P. 2022 a. Fragment ary remains of head and caudal region. The 
rays of the caudal fin considerably overlap the extremities 
of the supporting bones. Egerton Coll. 

P. 875. Fragments of head and anterior dorsal fin. Egerton Coll. 



C(ELACANTH1D.£. 



413 



Undina (?) barroviensis, A. S. Woodward. 



1890. Undina barroviensis, A. S. Woodward, Ann. Mag. Nat. Hist. [6] 
vol. v. p. 436, pi. xvi. fig-. 5. 

Type. Fish, wanting paired fins ; British Museum. 

An imperfectly definable species, known only by the specimen 
mentioned below. Fin-rays not expanded distally, with more 
widely-spaced articulations than in the typical species ; principal 
caudal fin consisting of about 16-18 rays above and below. Scales 
ornamented with few, large, irregular, elongated tubercles, some- 
times subdivided transversely. 

Form. § Log. Lower Lias : Barrow-on-Soar, Leicestershire. 

21335, P. 3343. Type specimen, in counterpart, described and 
figured, loc. cit. Purchased, 1847, and Ennislcillen Coll. 

The specimens mentioned below probably indicate an undetermined 
species of Undina, as remarked by the present writer in Proc. Geol. 
Assoc, vol. xi. (1890), p. 292 :— 

P. 4277. Pterygo-suspensorial bone figured, loc cit. pi. iii. fig. 6 ; 
Stonesfield Slate, near Oxford. Ennislcillen Coll. 

P. 3793. A more imperfect example of the same bone ; Stonesfield 
Slate. Ennislcillen Coll. 

P. 4277 a. Jugular plate, resembling a specimen figured by C. Pre- 
vost, Ann. Sci. Nat. vol. iv. (1825), pi. xviii. fig. 20. 

Enniskillen Coll. 



Genus LIBYS, Miinster. 
[Neues Jahrb. 1842, p. 45.] 

Fin-rays broad and robust, often expanded, and closely articulated 
in the distal half ; the preaxial rays of the first dorsal and caudal 
fins granulated. Parafrontal and circum orbital bones with a regular 
series of very large, broad vacuities or superficial excavations ; scales 
ornamented with irregularly disposed, elongated tubercles. 

This genus is closely related to Undina, and was first elucidated 
by 0. M. Reis (Palaeontographica, vol. xxxv. 1888, p. 37.). The 
vacuities or excavations in the parafrontal and circumorbital bones 
probably imply a large development of the mucus-secreting follicles 
of the sensory canals. 



414 CKOSSOPTERYGII. 

Libys polyp terus, Miinster. 

1842. Libys poly pterus, G. von Miinster, Neues Jahrb. p. 45. 

I860. Cadaccmthus (Undina) kohleri,T. H. Huxley (errore), Figs. & 

Descrips. Brit. Organic Remains (Mem. Geol. Surv.), dec. xii. 

p. 42. 
1888. Libys polyptems, O. M. Reis, Palseontographica, vol. xxxv. 

pp. 37, 50, pi. iii. figs. 1-11. 

Type. Fragment of head ; Palasontological Museum, Munich. 

The type species, imperfectly known. Jugular plates long and 
narrow, the maximum breadth being contained about five and a 
half times in the total length. Scales [so far as known] ornamented 
with large, closely arranged, elongated tubercles. 

This provisional diagnosis is given, on the assumption that the 
specimen mentioned below is correctly determined. 

Form. fyLoc. Lower Kimmeridgian (Lithographic Stone) : Bavaria. 

P. 3337. Specimen described by Huxley, loc. cit., under the name 
of Coelacanthus (Undina) kohleri ; Kelheim. The head 
exhibits the excavated parafrontals, regarded as character- 
istic of the genus Libys; but a few scales in advance of 
the first dorsal fin are indistinguishable from those of the 
typical Undina penicillata, and Huxley may be correct 
in describing the ornamentation of the cranial bones as 
having "disappeared" accidentally. The narrow jugular 
plates are well displayed from the inner aspect, each 
measuring about O06 in length and 0-11 in maximum 
breadth. EnnisTciXlen Coll. 

Libys superb us, Zittel. 

1887. Libys svperbus, K. A. von Zittel, Handb. Palseont. vol. iii. p. 175, 
woodc. fig. ] 79. 

1888. Libys svperbus, 0. M. Reis, Palseontographica, vol. xxxv. pp. 41, 
50, pi. ii. figs. 1-4. 

Type. Nearly complete individual ; Palaeontological Museum, 
Munich. 

Body short and robust ; head with opercular apparatus occupying 
less than one quarter of the total length. Jugular plates broad, 
the maximum breadth being contained about three and a half times 
in the total length ; ornamented with few fine striae. Scales with 
a sparse ornament of elongated tubercles. 

Form. Sf Loc. Lower Kimmeridgian (Lithographic Stone) : Ba- 
varia. 

Xot represented in the Collection. 



C(elacantiiidj:. 415 

Genus COCCODERMA, Quenstedt (emend. Reis). 
[Der Jura, 1858, p. 810 (Kolchoderma).'] 

Supplementary caudal fin stout and prominent, the rays of all 
the fins broad and robust, often expanded, and closely articulated 
in the distal portion ; small granulations on the preaxial rays of 
the first dorsal and caudal fins. External ornament consisting of 
sparse tubercles, which become numerous and spinous on the scales ; 
parafrontal and circumorbital bones plate-like, without superficial 
excavations. 

This genus was founded upon a detached pterygo-suspensorial 
bone, described as a problematical fossil by Quenstedt. The definition 
here given is based upon the researches of 0. M. Reis (Paloeontogr. 
vol. xxxv. 1888, p. 60), who recognizes three species, of which 
there are no specimens in the Collection : — 

Coccoderma gigas, 0. M. Reis, loc. cit. (1888), p. 57, pi. iii. 
fig. 17-19. — Lithographic Stone (Lower Kimmeridgian) ; 
Bavaria. [Jaws ; Munich Museum.] 

Coccoderma substriolatum, 0. M. Reis, ibid. p. 51 : Macropoma 
substriolatum, T. H. Huxley, Figs. & Descrips. Brit. 
Organic Remains (Mem. Geol. Surv. 1866), dec. xii. 
p. 39, pis. ix., x. — Kimmeridge Clay ; Cottenham. [Skull 
and portion of trunk ; Woodwardian Museum, Cambridge.] 

Coccoderma suevicum, F. A. Quenstedt, Der Jura (1858), p. 810, 
pi. 100. fig. 14 ; O.M. Reis, loc. cit. p. 51, pi. v. figs. 1,2, 
4, 8, 11, pi. iv. fig. 16 : Undina major, A. Wagner, Abh. 
math.-phys. CI. k.-bay. Akad. Wiss. vol. ix.(1863), p. 697 : 
Coelacanihus major, R. von Willemoes-Suhm, Paloeontogr. 
vol. xvii. (1869), p. 82. — Lithographic Stone (Lower 
Kimmeridgian) ; Wiirtemberg and Bavaria. [Pterygo- 
suspensorial bone ; Tubingen Museum. Type species.] 

Undefined fragments from the Bavarian Lithographic Stone are also 
named Coccoderma nudum, Reis (loc. cit. p. 60, pi. iii. fig. 16, pi. v. 
fig. 1), and C. bavaricum, Reis (ibid. p. 60, pi. v. fig. 2). The 
types are in the Munich Museum. 

Genus HEPTANEMA, Bellotti. 

[C. Bellotti, in A. Stoppani, Studii Geol. e Paleont. Lombardia, 
1857, p. 435.] 

Fin-rays robust and straight, not expanded, and only articulated 
for a relatively short extent distally ; the preaxial rays of the first 
dorsal and caudal fins with a double series of upwardly-pointed 



416 CROSSOPTERYGl 1 . 

denticles ; [supplementary caudal fin " rudimentary or absent"]. 
Operculum and jugular plates ornamented -with hollow spinous 
tubercles ; the scales with a large median spinous tubercle flanked 
by one or two pairs of similar but smaller tubercles. 

There are no examples of this genus in the Collection, but the 
following species are recognized : — 

Heptanema paradoxum, C. Bellotti, in A. Stoppani, op. cit. 1857, 
p. 435 ; W. Deecke, Palaeontogr. vol. xxxv. (1889), p. 112, 
pi. vii. fig. 3. — Upper Keuper ; Perledo, Lake of Como. 
[Imperfect fish ; Milan Museum. The type species.] 

Heptanema willenioesi, 0. M. Reis, Palaeontogr. vol. xxxv. (1888), 
p. 64, pi. iii. figs. 20, 21 : Macropoma willemoesii, B. Vetter, 
Mittheil. k. mineral.- geol. Mus. Dresden, pt. iv. (1881), p. 1, 
pi. i. fig. 1. — Lower Kimmeridgian (Lithographic Stone) ; 
Bavaria. [Royal Mineralogical Museum, Dresden.] 

An undetermined Coelacanth, possibly of this genus, from the 
Keuper of Coburg, is also noticed and figured by H. A. C. Berger, 
Verstein. Sandst. Coburg. Gegend (1832), p. 18, pi. i. fig. 2. 

Genus MACROPOMA, Agassiz. 
[Poiss. Foss., Feuilleton, 1835, p. 55.'] 

Maxilla provided with irregularly-arranged large and small coni- 
cal teeth ; vomerine and palatine teeth large and clustered ; pterygo- 
suspensorium covered internally with granules, passing into small 
conical teeth on the inferior margin of the bone ; splenial with small 
conical teeth. The rays of all the fins robust and straight, not 
expanded, and only articulated for a relatively short extent distally ; 
a double series of small, upwardly -pointing denticles on almost all 
the rays of the first dorsal and caudal fins ; [supplementary caudal 
fin unknown]. Cranial roof-bones externally pitted and tubercu- 
lated ; the other membrane-bones externally tuberculated, and the 
scales ornamented with elongated prickles. 

The supplementary caudal fin in this genus is sometimes stated 
to be rudimentary or absent ; but the condition of preservation of 
known specimens does not as yet justify a definite assertion. 

Macropoma mantelli, Agassiz. 

[Plate XIY. fig. 3.] 

1822. Amia ? kioesiensis, G. A. Mantell, Foss. South Downs, p. 239, 

pis. xxx vii., xxxviii. 
1835. Macropoma mantellii, L. Agassiz, Poiss. Foss., Feuill. p. 55. 



CXELACANTHID^. 417 

1844. Macropoma manteUii, L. Agassiz, ibid. vol. ii. pt. ii. p. 174, 
pi. lxv. a(bis)-d. 

1849. Macropoma mantelU, W. C. Williamson, Phil. Trans, p. 462, 
pi. xlii. figs. 25, 26, pi. xliii. figs. 27-30. 

1850. Macropoma mantelli, F. Dixon, Foss. Sussex, p. 368, pi. xxxiv. 
fig. 2. 

1866. Macropoma manteUii, T. H. Huxley, Figs. & Descrips. Brit. 

Organic Remains (Mem. Geol. Surv.), dec. xii. p. 27, pis. vii., viii. 
1888. Macropoma mantelli, A. S. Woodward, Proc. Geol. Assoc, vol. x. 

p. 303. 

Type. Fish ; British Museum. 

The type species, attaining a maximum length of about 0*55. 
Trunk robust but elongated ; head and opercular apparatus occupying 
about one quarter of the total length ; jugular plates about four 
times as long as broad. First dorsal fin large, consisting of not 
less than 8 robust rays ; second dorsal relatively small, consisting 
of numerous slender rays ; principal caudal fin comprising about 
18-20 stout rays above and below. Mandible, post-maxillary, 
jugular plates, and operculum ornamented with numerous minute 
rounded tuberculations ; parafrontals, postorbitals, and suborbitals 
pitted ; tubercles of scales large, elongated, numerous, and closely 
arranged. 

Although the specific name leivesiensis strictly pertains to this 
form, it seems advisable to employ the universally-adopted name of 
mantelli in honour of its discoverer. 

Form. Sf Loc. Senonian and Turonian : S.E. England. 

4219. Type specimen, figured by Mantell, op. cit. pi. xxxvii., and 
by Agassiz, torn. cit. pi. lxv. a. bis, fig. ". ; Lewes, Sussex. 

Mantell Coll. 

4253. Head and anterior abdominal region ; the head figured ibid. 
pi. lxv. a. bis, fig. 2 ; Lewes. Mantell Coll. 

4269. Abdominal region, showing portions of dorsal and pelvic fins, 
and well-preserved squamation, figured ibid. pi. lxv. b ; 
Lewes. Mantell Coll. 

4256. Portion of trunk showing air-bladder, much distorted, a small 
coprolite, the pelvic bones, and some of the pelvic fin-rays, 
figured ibid. pi. lxv. c. fig. 1 ; Lewes. Mantell Coll. 

4264. Portion of jaws, figured ibid. pi. lxv. c. fig. 2 ; Lewes. 

Mantell Coll. 

4251. Portion of head and abdominal region, the jugular plate, 
PAKT ii. 2 E 



418 CROSSOPTEEYGII. 

angular, and inferior half of the clavicle of the right side 
figured ibid. pi. lxv. c. fig. 3 ; Lewes. The clavicle is 
shown from the inferior aspect, which is concave, as 
noted by Huxley, loc. cit. p. 33. Mantell Coll. 

4298. Caudal fin-rays, figured ibid. pi. lxv. c. figs. 4, 5 ; Lewes. 

Mantell Coll. 

4270. Head and anterior portion of trunk, showing air-bladder, 
figured ibid. pi. lxv. d. fig. 1 ; Lewes. The cluster of 
teeth on the supposed vomers is prominent ; the left 
dentary is well preserved ; and the left clavicle is described 
and figured by Huxley, loc. cit. p. 33, pi. vii. fig. 4 b. 

Mantell Coll. 

4237. Head, seen from the right side, figured by Agassiz, torn. cit. 
pi. lxv. d. fig. 2, and by Huxley, loc. cit. pi. vii. fig. 3 ; 
Lewes. Mantell Coll. 

4252. Head and abdominal region, the head figured by Agassiz, 
torn. cit. pi. lxv. d. fig. 3, and also described and figured by 
Huxley, loc. cit. p. 37, pi. vii. fig. 6 ; Lewes. Mantell Coll. 

115. Imperfect head and trunk in counterpart; Hailing, Kent. 
Portions of the fins and their supporting bones are shown, 
and the rays of the pectoral are described and figured by 
Huxley, loc. cit. p. 33, pi. vii. fig. 5 (wrongly quoted as 
no. 4258). Purchased, about 1836. 

25782. Imperfect head and trunk, wanting all the fins except a 
portion of the principal caudal; Sussex. The head is 
figured by Dixon, op. cit. pi. xxxiv. fig. 2. The tuberculated 
surface of the jugular plates is noticed by Huxley, loc. cit. 
p. 38 ; and the operculum, angular, post-maxilla, frontals, 
and parietals are similarly ornamented. The upper half 
of the clavicle is shown, is quite smooth, and does not 
appear to have been exposed. Dixon Coll. 

49834. Imperfect head and trunk, displaying the air-bladder elon- 
gated by crushing ; New Pit, Lewes. The head exhibits 
the parafrontals, supposed maxilla, post-maxilla, angular 
and dentary bones ; and the tuberculated operculum and 
jugular plates are also well shown. Cajpron Coll. 

49836. Much crushed remains of head and trunk, displaying many 
of the bones, scales, and fin-rays; Lewes. The outer 
portion of the clavicle exhibits irregular longitudinal 
wrinkles. Cajpron Coll. 






CCELACANTIIIDJE. 



419 



P. 2051. Imperfect head and trunk, with remains of the median 
fins ; Sussex. Egerton Coll. 

49887. Kemains of head and fragment of abdominal region ; Sussex. 

C apron Coll. 

49833. Portions of head and abdominal region, with crushed remains 
of the air-bladder ; North Stoke, near Arundel. Among 
the best preserved bones are the operculum, jugular plates, 
suborbital, dentary, and supposed maxilla. 

Capron Coll. 

P. 4547. Imperfect head and anterior half of abdominal region, 
showing parts of the branchial apparatus noticed by 
Huxley, loc. cit. p. 39 ; near Maidstone. 

Ennislcillen Coll. 

47239. Imperfect head and abdominal region, and two portions of 

trunk ; Grey Chalk, Dover. Gardner Coll. 

35700. Portions of head and abdominal region ; Grey Chalk, Dover. 

Purchased, 1859. 

47240. Imperfect small head ; Grey Chalk, Dover. Gardner Coll. 

P. 3353. Head and opercular apparatus ; Grey Chalk, Dover. 

Ennislcillen Coll. 

P. 3352. Skull and mandible described and figured by Huxley, loc. 
cit. p. 33, pi. viii., the specimen being only two-thirds as 
large as the figures ; Sussex. Enniskillen Coll. 

4245, 4247, 4289. Three imperfect heads, the third showing the 
basi-branchial bone ; Sussex. Mantell Coll. 

39070. Head with portions of the branchial and opercular apparatus 
and the left clavicle ; Maidstone. The so-called maxilla 
and post-maxilla distinctly appear to be membrane-bones 
at the outer margin of the mouth. Bowerbank Coll. 

49094. Large imperfect head, displaying the bones of the mandible. 

Mrs. Smith's Coll. 

49837. Small, much crushed head and first dorsal fin ; Dorking. 

Capron Coll. 

P. 742. Three very imperfect heads ; Lewes, Egerton Coll. 

P. 4548. Imperfect large head, showing the post-maxilla and the 
superficial tuberculation both of that bone and the post- 
orbitals ; English Chalk. Enniskillen Coll. 

2e2 



420 CROSSOPTERYGII. 

43851. Fragment of head, displaying the dentary and the apparent 
separation of an extremely-tuberculated infra- dentary 
element ; Upper Chalk, Warne's Place, Rochester. 

Purchased, 1872. 

4246. Scattered remains of head, showing the inner aspect of the 
operculum, parietals, and the right pterygo-suspensorial, 
the latter noticed by Huxley, loc. cit. p. 36 ; Lewes. 

Mantell Coll. 

4238. Fragment showing parts of the branchial arches and the 
imperfect ba si-branchial, inferior aspect ; Lewes. 

Mantell CoU. 

28388. Similar specimen, showing also the inferior two-thirds of 
the clavicles and portions of the infraclavicles ; Lewes. 
The infraclavicle (PI. XIY. fig. 3, i.cl) is an elongated, 
slender bone, sharply bent at a point one third of its total 
length from the inferior extremity, and this third appears 
to consist of a triangular expansion in an almost horizontal 
plane ; the upper two-thirds are of spatulate form over- 
lapping the outer face of the lower end of the clavicle (cl.). 
The figure shows the right infraclavicle, outer and partly 
inferior aspect, restored in outline from evidence afforded 
by the element of the left side. Mantell Coll. 

4260. Portion of abdominal region, with fragments of head, the 
air-bladder, first dorsal fin, and the basal bone of the 
second dorsal ; Lewes. The basal bone of the first dorsal 
fin is noticed by Huxley, loc. cit. p. 38. Mantell Coll. 

4216-17, 4221, 4236, 4241, 4243-44, 4250, 4258-59, 4261-62. 

Ten examples of the trunk, displaying various portions 
of the axial skeleton, the air-bladder, median fins, and 
scales ; Lewes. Nos. 4216, 4241, and 4250 are preserved 
in counterpart, and the third exhibits, in transverse sec- 
tion, the longitudinal series of very large hollow spines 
occurring upon the middle of several horizontal rows of 
scales ; the perforations are at first sight suggestive of 
the openings of sensory canals. Nos. 4236, 4250 show the 
distal articulation of the caudal fin-rays. Mantell Coll. 

25789. Imperfect trunk exhibiting scales and portions of the median 
fins; Sussex. Dixon Coll. 

25944. Imperfect trunk, showing an apparently lobate pelvic fin, 
noticed by Huxley, loc. cit. p. 33 ; Sussex. Dixon Coll. 



CCELACANTHID.E. 421 

25923 a. Fragments of abdominal and caudal region ; Sussex. 

Dixon Coll. 

41669. Fragments of trunk, showing the first dorsal fin, with its 
basal bone, and the ornamentation of spinelets upon the 
scales ; Kent (?). Toulmin- Smith Coll. 

P. 6287. Trunk with portions of the second dorsal, anal, and prin- 
cipal caudal fins. 

43851 a. Specimen showing the basal bone of the first dorsal fin 
and some of the fin-rays ; Upper Chalk, Warne's Place, 
Bochester. Purchased, 1872. 

49096. Fragment of caudal region, with part of the principal caudal 
fin ; Kent. Mrs. Smith's Coll. 

49832, 49835. Two portions of trunk, the first showing well pre- 
served scales, some with the large median spines, and 
exhibiting considerable variation in the ornamentation ; 
Upper Chalk, Guildford. Cajoron Coll. 

P. 6288. Small trunk with portions of the dorsal, principal caudal, 
and each of the pelvic fins. 

P. 742 a. Fragment of trunk showing part of a pectoral fin, the lobe 
apparently covered with thin tuberculated scales ; Sussex. 

Egerton Coll. 

P. 5407. Fragment of trunk with well-preserved scales, exhibiting 
much variation in the ornamentation ; Lewes. 

Presented by P. E. Coombe, Esq., 1888. 

P. 4638. Caudal region of very small individual, probably young of 
this species ; Lewes. EnnisJcillen Coll. 

4224-26, 4228, 4232-33. Portions of air-bladder ; Lewes. 

Mantell Coll. 

The Collection includes a large number of coprolites, the majority 
probably referable to Macropoma, though some may pertain to 
Elasmobranchs. The following series may be enumerated : — 

4274, 4350, 4354. Three specimens noticed and figured by Mantell, 
Foss. S. Downs, pp. 103, 158, 310, pi. ix. figs. 3, 7, 10, as 
" supposed aments or cones of a species of Larch " : Lewes, 
Hamsey, and Steyning. Mantell Coll. 

4332, 4338, 4334, 4276-77, 4319, 4275, 4273. Eight specimens, 



422 CROSSOPTERYGII. 

described and figured by Agassiz, Poiss. Foss. vol. ii. pt. ii. 
p. 177, pi. lx. a. bis, figs, 1-5, 7-11 ; Lewes. 

Mantell Coll. 

25792. The stouter of the two specimens figured by Dixon, Foss. 
Sussex, pi. xxx. fig. 33 j Sussex. Dixon Coll. 

49934. Crushed specimen ; Lower Chalk, Southeram Pit, Lewes. 

Capron Coll. 
P. 5410. Five specimens ; Lewes. 

Presented by P. E. Coombe, Esq., 1888. 

49929. Three small specimens ; Upper Chalk, Guildford. 

C apron Coll. 

47258. Ten specimens ; Grey Chalk, Dover. Gardner Coll. 

35553. Portions of coprolites ; Greensand, Tournay. 

Presented by Thomas Davidson, Esq., 1859. 

A species of Macropoma closely related to the typical M. mantelli, 
and not satisfactorily distinguished by the published diagnosis, is 
described as Macropoma speciosum, A. E. Eeuss, Denkschr. k. Akad. 
Wiss. Wien, math.-naturw. CI. vol. xiii. (1857), p. 33, pis. i., ii. 
The type specimen is a nearly complete fish, wanting the paired fins, 
from the Turonian of the Weissenberg, Bohemia, and is now pre- 
served in the Eoyal Bohemian Museum, Prague. It is said to be 
distinguished from M. mantelli by the more slender form of the 
trunk, the number of the fin-rays, and the proportions of the pterygo- 
suspensorium ("infraorbital"); and a restoration is published by 
A. Fritsch (Eept. u. Fische bohm. Kreideform. 1878, p. 26, pi. iii.), 
partly based upon the type specimen, partly upon more recently 
discovered examples. The cranial osteology of the latter is criticized 
by 0. M. Eeis, Palaeontographica, vol. xxxv. (1888), p. 63, pi. iv. fig. 2. 

A second species of Macropoma in the Turonian of Bohemia is 
determined by Fritsch (op. cit. p. 31, pi. iv. figs. 2-7) under the name 
of M. forte. The type specimen, also from the 'vVeissenberg, near 
Prague, is an imperfect head with opercular apparatus and some an- 
terior scales, now preserved in the Eoyal Bohemian Museum ; it is 
described as being characterized by scales relatively twice as large 
as those of M. speciosum, while the frontal bones are somewhat 
broader. 

Doubtful scales from the Planerkalk of Strehlen, near Dresden, 
are assigned to Macropoma mantelli by H. B. Geinitz, Foss. Fisch- 
schuppen Planerkalk. Strehlen (1868), p. 47, pi. iv. figs. 8, 9, and 
Palaeontographica, vol. xx. pt. ii. (1875), p. 218, pi. xliv. figs. 1, 2. 
The specimens are now in the Eoyal Museum, Dresden. 



A.CTINOFTEKTGIT. 423 

Suborder IV. CLADISTIA. 

Notochord more or less constricted and replaced by ossified 
vertebra. Baseosts in median fins rudimentary or absent ; axonosts 
in regular series, equal in number to the apposed dermal fin-rays. 

The di- or tri-basal character of the pectoral fins, in conjunction 
with other features, may perhaps justify the recognition of this 
group as a distinct order. It is represented only by the family of 
Polypteridoe (genera Polypterus and Calamoichthys), at present 
restricted to African rivers. No extinct types are known. 



Order IT. ACTINOPTERYGII. 

Paired fins non-lobate, having an extremely abbreviated endo- 
skeletal portion, and the dermal rays prominent ; caudal fin abbre- 
viate-diphycercal, heterocercal, or horaocercal. A single paired series 
of transversely elongated rays, with or without an anterior azygous 
element, developed in the branchiostegal membrane between the 
mandibular rami. 

Division A. — Pelvic fins with well-developed baseosts ; median 
fins with dermal rays more numerous than the endoskeletal 
supporting elements ; tail diphycercal or heterocercal. 
In the living foirnis — optic nerves not decussating but form- 
ing a chiasma, intestine with a spiral valve. 

Suborder I. CHONDROSTEL 

Notochord more or less persistent. Axonosts and baseosts of median 
fins in simple, regular series. Membrane-bones of pectoral arch 
comprising a pair of infraclavicular plates. 

In all known members of this suborder there is a single dorsal and 
anal fin, well separated from the caudal. 

Synoj)sis of Families. 

A. Ascending Series. 

Trunk elongate-fusiform ; tail he- 
terocercal ; teeth slender, conical 
or styliform Pal^oniscid^j (p. 424). 



424 ACTINOPTEETGII. 

Trunk deeply fusiform; tail hetero- 

cercal ; principal dentition on 

pterygoid and spleuial bones, 

obtuse Platysomatid^: (p. 527). 

Trunk elongate-fusiform ; tail ab- 

breviate-heterocercal ; teeth 

slender, styliform Catopterid^ (Part III.). 

B. Degenerate Series. (See Part III.) 
Cranial shield without a median 

azygous series of bones ; 

branchiostegal rays present ; no 

teeth in adult; tail heterocer- 

cal ; squamation rudimentary 

or absent, except on the upper 

caudal lobe Chondbosteid^:. 

Cranial shield without a median 

azygous series of bones ; 

branchiostegal rays present ; 

teeth in adult ; tail diphycer- 

cal ; longitudinal series of 

scutes upon trunk Belonorhynchidje. 

Cranial shield with a median azygous 

series of bones ; no branchio- 
stegal rays ; no teeth in adult ; 

tail heterocercal ; longitudinal 

series of scutes upon trunk. . . . Acipenserid^e. 
Cranial shield with a median 

azygous series of bones ; no 

branchiostegal rays ; minute 

teeth in adult ; tail heterocercal; 

squamation rudimentary or 

absent, except on the upper 

caudal lobe Polyodontid^:. 



Family PAL^EONISCID^E. 

Trunk elongate or elongate-fusiform ; tail heterocercal ; scales 
rhombic (rarely in part cycloidal), ganoid. Head-bones well-deve- 
loped, ganoid ; no median series of cranial roof-bones ; teeth slender, 
conical or styliform ; eye far forwards and snout prominent ; man- 
dibular suspensorium more or less obliquely directed backwards and 
downwards. A series of broad branchiostegal rays, the most anterior 
pair especially large, with a small median element. Dorsal fin single 
and not much extended. 

This is a somewhat comprehensive family, and it is not unlikely 



tal;eoniscid.e. 425 

that further researches may lead to its dismemberment. The most 
important contributions to present knowledge of the typical Palaeozoic 
genera have hitherto been made by 11. H. Traquair 1 j and the ad- 
ditional observations recorded in the following pages chiefly result 
from the study of Mesozoic forms. 

Fig. 54. 




Palcsoniscus macropomus, Ag. — Head and pectoral arch, restored in outline, by 
R. H. Traquair. 

a.f, anterior frontal ; a.g, angular ; br, branchiostegal rays ; cl, clavicle ; d, 
dentary; e, ethmoid ; /, frontal ; i.cl, infraclavicle ; Lop, suboperculum ; 
mx, maxilla ; n, narial opening ; op, operculum ; p, parietal ; p.cl, post- 
clavicle ; p.op, preoperculutn ; p.t, post-temporal; pmx, premaxilla; 
s.cl, supraclavicle ; s.o, circumorbital ring and suborbitals; s.t, supra- 
temporal ; sq, squamosal. 

No precise particulars are forthcoming as to the ossifications in 
the chondrocranium, but the dermal or membrane -bones of the head 
are conspicuous and well-known. The cranial roof is provided with 
a continuous shield, of which a small pair of parietals (fig. 54, p) 
and the flanking squamosal plates (sq) form the hinder portion, while 
a large pair of elongated frontals (/), with or without a separate pair 
of lateral plates, constitutes the middle portion ; a large, azygous eth- 
moidal or rostral plate (e) completes the shield anteriorly, is flanked 
on each side by a so-called anterior frontal element (a.f), and with 
the latter surrounds the pair of narial openings (n). The base of 
the cranium also has the ordinary, well-developed parasphenoid 
membrane-bone. The jaws and cheek are likewise covered with 

1 Monogr. Palaeont Soc. 1877; Quart. Journ. Geol. Soc. vol. xxxiii. (1877) ; 
and Trans. Roy. Soc. Edinb. vol. xxx. (1881, with plates in 1887). The Pahe- 
ontographical Society's Monograph appears to have been abandoned, and has 
been replaced in recent years by numerous desultory notes without figures. 



426 ACTINOPTERTGII. 

bony splints. The maxilla (m.v) is a narrow, elongated element, 
much expanded behind the eye ; the premaxilla (pmx) is compara- 
tively small and insignificant. Surrounding the eye is a narrow ring 
of four thin bones (circumorbitals) bounded behind by others of the 
" suborbital " series (s.o) ; and the space between the latter, the 
cranial roof, maxilla, and opercular apparatus is covered by a single 
bent bone, interpreted by Traquair as preoperculum (p. op). In 
the mandible the articular portion of the meckelian cartilage is os- 
sified, and the rest is ensheathed outside by a very large dentary 
(d) and a small angular (ag), while its inner face is equally covered 
by an extensive laminar splenial. Both the splenial and dentary, as 
a rule, bear teeth. The hyomandibular element of the suspensorium 
is well ossified superficially and is thus usually preserved, but no 
symplectie has been noticed ; the former is much elongated, and 
somewhat bent at about the position of the lower border of the 
operculum. The ptery go-quadrate seems to be ossified at least at the 
quadrate articulation ; and there is evidently a large, elongated 
membrane-bone ensheathing its inner or oral aspect. The oper- 
culum {op) is suspended from the hyomandibular, and is usually 
narrow, bounded below by a large suboperculum (i.op.), often with 
indications of a feebly developed interoperculum. Beneath the sub- 
operculum, the opercular fold is strengthened by a series of lamelli- 
form branchiostegal rays (hr), which meets the corresponding series 
of the opposite side in front, and terminates in an anterior azygous 
element at the symphysial angle of the mandible. The branchial 
arches are sometimes seen to be ossified. 

In the axial skeleton of the trunk, the notochord must have been 
persistent, and there is as yet no definite evidence of ossifications in 
its sheath. The neural arches and spines throughout the trunk, and 
the haemal arches, with their spines in the caudal region, are super- 
ficially ossified, and are thus observed when there is no obscuring squa- 
mation ; but there are no traces of ribs in any genus, the abdominal 
haemal arches being merely small short pieces of cartilage. In the 
only genus in which they have been well displayed (Coccolejns), the 
neural spines are not fused with the supporting arches in the abdom- 
inal region, but both these and the haemal spines are firmly fixed to 
their arches in the tail ; at the base of the caudal fin the haemals are 
much enlarged for the direct support of the dermal rays, while the 
neurals become gradually aborted, and there is a series of distinct 
supporting ossicles beneath the fulcra of the upper caudal lobe 1 . 

1 The characters of the axial skeleton are to some extent shown in Ann. Mag. 
Nat. Hist. [6] vol. v. pi. xvi. figs. 2, 4; but more satisfactory information -will 
appear in Mem. Geol. Surv. N.S. Wales, Pahsont. no. 9, pis. i.,ii. 



PAL^ONISCTDiE. 427 

It is not certain whether any narrow chain of suprateraporal 
plates (fig. 54, s.t) is present behind the cranial shield ; but there is 
a very large post-temporal (p.t) on each side, above the operculum 
and pectoral arch. The membrane-bones of the latter are all 
conspicuous and externally ornamented ; the clavicle (d) having a 
short inferior limb, and being bounded in front by a small 
triangular infraclavicle (i.cl) ; the supraclavicle (s.cl) deep and 
narrow, traversed above by the " lateral line," and bounded behind 
at its articulation with the clavicle by a small postclavicle (p.cl). 
Nothing is known of the scapulo-coracoid cartilage, but a small series 
of radials is sometimes seen at the base of the pectoral fin-rays. The 
basipterygium (axonost) of the pelvic fin has not yet been observed in 
any genus, probably on account of non-ossification ; but the radial 
cartilages (baseosts) form a well-developed series of elongated ele- 
ments in Coccolepis australis, and it is probable that thisis a common 
feature of the family. The dermal rays in all the fins are, as a 
rule, delicate, articulated, and bifurcated distally ; a few genera 
only exhibiting simple rays, and some others having rays without 
articulation in the pectoral fin. In the median fins, the endoskeletal 
supports are always less numerous than the dermal rays, and they 
never appear to overlap the neural spines of the axial skeleton 
beneath. In some of the earlier types (e. g., Elonichthys and 
Pygopterus) these supports are distinctly shown in the dorsal fin to 
be arranged in two series — the proximal of slender axonosts, and 
the distal of stout baseosts ; but in the Jurassic Coccolepis the 
baseost series seems to have completely disappeared. The dermal 
rays are to a slight extent imbricating, and the stouter portions are 
ordinarily coated more or less with ganoine. 

The scales are typically rhombic, and united on the flanks by a 
peg-and-socket articulation ; but in some genera (e. g., Cryphiolepis 
and Coccolepis) the overlap of the successive series is so extensive 
that they become essentially cycloidal, and the internal rib, with 
its articular facettes, disappears. All the scales are more or less 
coated with superficial ganoine, and the course of the lateral line is 
marked by a series of perforations, which terminate at the base of 
the upper caudal lobe. There is a dorsal and ventral series of 
azygous ridge-scales which are often enlarged, especially at the 
bases of the fins and upon the superior caudal lobe ; and these are 
ordinarily continued by fulcra on the front margin of the fins. It is 
also worthy of note that the downward and backward trend of the 
scales is suddenly reversed at the base of the upper caudal lobe ; 
and even when all the other scales are rudimentary or absent, 
the squamation of this lobe is always robust. 



428 



ACTIN0PTEKYG1I. 



With regard to the arrangement of the genera of Palaeoniscidae, 
it must be remarked that the scheme adopted below is merely a 
provisional attempt to follow the lines of evolution. It may be 
regarded as tolerably well established that (i.) the obliquity of the 
suspcnsorium, (ii.) the loss of the baseosts in the median fins, (iii.) 
the advanced position of the dorsal fin, and (iv.) the increasing 
imbrication of the scales, are characters resulting from specializa- 
tion. Ooccolepis, in which all these features are combined, thus 
terminates the regular series. 

Synopis of Genera. 

A. Mandibular suspensorium nearly vertical ; 

scales rhomboidal. 

I. Fin-rays dichotomous ; caudal fin 

forked. 

Scales sculptured ; a continuous series 
of enlarged ridge-scales; teeth 
minute Canubius (p. 430). 

Scales smooth or in part faintly sculp- 
tured ; teeth large, styliform, in 
regular close series ; oral border 
of maxilla straight Gonatodus (p. 434). 

As Gonatodus, but oral border of 
maxilla sharply deflected at the 
posterior expansion Drydenius (p. 437). 

Scales smooth, or in part faintly sculp- 
tured ; teeth minute Amblypterus (p. 437). 

II. Fin-rays simple ; caudal fin obliquely 

truncated. 
Scales sculptured, some flank-scales 
very deep ; teeth minute ; fins 
small, with fulcra Euryhpis (p. 448). 

B. Mandibular suspensorium oblique. 

I. Fin-rays dichotomous ; caudal fin 
forked, 
i. Dorsal fin remote, behind the anal. 
Scales minute ; well - developed 

laniary teeth Cheirolepis (p. 451). 

ii. Dorsal fin remote, not extending 

behind the anal; laniary teeth 

well-developed. 

Trunk elongated ; anterior pectoral 

fin-rays articulated in distal 

third ; scales small, finely 

striated, deep and narrow on 

flank, with prominent inner keel. Nematoptychius (p. 457). 



PALiEONISClDiE. 



429 



anterior pectoral 
fin-rays articulated in distal 
third; dorsal and anal fins 
short-based; scales large, con- 
centrically striated Cycloptychius (p. 459). 

Trunk fusiform ; anterior pectoral 
fin-rays articulated distally ; 
dorsal and anal fins short-based ; 
scales large, obliquely striated. . Rhadinichthys (p. 461). 

Trunk elongated ; anterior pectoral 
fin - rays articulated distally ; 
anal fin much extended ; scales 
small, smooth or feebly striated. Pygopterus (p. 470). 

Trunk elongated ; dorsal and anal 
fins short-based ; scales small, 
smooth or feebly striated .... Trachelacanthus (p. 475). 

[Imperfectly defined.] Fins large 
and somewhat extended ; scales 
obliquely striated Urolepis (p. 475). 

Dorsal fin in advance of anal ; den- 
tition feeble. 

Fins small, fulcra absent ; scales of 

flank rudimentary or absent . . Phanerosteon (p. 476). 

Fins small, fulcra minute ; scales 
well-developed, with oblique 
sculpturing Palceoniscns (p. 476). 

Fins small, fulcra absent ; scales very 

thin, with oblique sculpturing . . Apateolepis (p. 486). 

Trunk much elongated ; scales nar- 
row and very thin Actinophorus (p. 486). 

Dorsal fin in advance of anal; 
laniary teeth well-developed. 

Fins large, with fulcra ; pectoral fin- 
rays all articulated ; scales large 
or of moderate size, slightly 
overlapping, obliquely sculp- 
tured JElonichthys (p. 487). 

Fins large, with fulcra ; pectoral fin- 
rays unarticulated (?) ; dorsal 
and anal fins short-based ; scales 
large, thick, deeply overlapping, 
obliquely sculptured Acrolepis (p. 501). 

Fins large, with fulcra ; pectoral fin- 
rays unarticulated, except dis- 
tally ; anal fin much extended ; 
operculum relatively narrow 
and deep ; scales large, thick, 
well overlapping, obliquely 
sculptured Gyrolepis (p. 510). 



430 ACTIBTOPTERTGII. 

Fins large ; pectoral fin-rays un- 

articulated, except distally ; anal 

and pelvic fins extended ; scales 

large,thick, slightly overlapping, 

obliquely sculptured ; dorsal 

ridge-scales much enlarged. . . . Atherstonia (p. 514). 
Fins large, fulcra minute ; dorsal 

and anal fins short-based ; scales 

very small, obliquely sculptured. Myriolepis (p. 515). 
Fins large, fulcra minute ; pectoral 

fin-rays unarticulated, except 

distally ; dorsal and anal fins 

somewhat extended ; scales 

small, thick, slightly overlap- 
ping, obliquely sculptured .... Oxygnathus (p. 516). 
Fins large, with fulcra ; pectoral fin- 
rays articulated ; dorsal and 

anal fins short-based ; scales of 

moderate size, thick, slightly 

overlapping, coarsely ridged and 

serrated Centrolepis (p. 520). 

Fins large, with fulcra ; pectoral fin- 
rays articulated; dorsal and 

anal fins short-based ; scales 

large, thin, very deeply over- 
lapping, externally striated. . . . Cryphiohpis (p. 522). 
Fins large, fulcra minute or absent ; 

dorsal and anal fins short-based ; 

scales large, thin, very deeply 

overlapping, externally tuber- 

culated Coccolepis (p. 523). 

II. Fin-rays simple ; caudal fin obliquely 
truncated. 
Teeth minute ; dorsal fin extended, 

not remote; scales sculptured, 

and dorsal ridge-scales much 

enlarged Holurus (p. 526). 



Genus C ANOBIUS, Traquair. 

[Trans. Boy. Soc. Edinb. vol. xxx. 1881, p. 46.] 

Trunk fusiform. Mandibular suspensorium nearly vertical ; 
snout rounded, slightly projecting over the mouth ; gape small [and 
teeth unknown]. Fin-rays articulated and distally bifurcating ; 
fulcra minute. Dorsal and anal fins short-based, triangular- 



PALJEONISCIDiE. 431 

acuminate, nearly opposite, the former arising only slightly in 
advance of the latter ; caudal fin deeply cleft, inequilobate. Scales 
sculptured, somewhat deeper than broad on the anterior portion of 
the Hank ; a prominent series of dorsal ridge-scales. 

Except in the characters of the head, there is much superficial 
resemblance between this genus and lihaclinichthys. 

Canobius ramsayi, Traquair. 

1881. Canobius ramsayi, R. H. Traquair, Trans. Roy. Soc. Edinb. 
vol. xxx. p. 47, pi. v. figs. 1-4. 

Type. Eish ; Geological Survey of Scotland. 

The type species, attaining a maximum length of about # 08. 
Maximum depth of trunk contained about three times in the 
total length. Head and opercular apparatus occupying little more 
than one-fifth of the total length ; snout very obtusely rounded ; 
external bones ornamented with coarse flattened corrugations, 
except the mandible, which is marked by finer and nearly parallel 
longitudinal ridges. Pelvic fins relatively small, arising somewhat 
nearer to the anal than to the pectorals ; dorsal and anal fins 
similar, almost completely opposed ; caudal fin very heterocercal, 
the upper lobe being about twice as long as the lower, and nearly 
equalling one-third of the entire length of the fish. Scales com- 
paratively smooth, rarely or never denticulated, but marked with 
few faint diagonal ridges and furrows, sometimes also with delicate 
vertical striae close to and parallel with the anterior margin of the 
exposed area. 

Form, fy Loc. Calciferous Sandstones (Cement-stone Group): 
Eskdale, Dumfriesshire. 

P. 4068. Three typical specimens, one being in counterpart. 

Purchased, 1883. 

P. 5981. Trunk with median fins, in counterpart. 

Purchased, 1889. 

Canobius elegantuhis, Traquair. 

1881. Canobius elegantulus, R. H. Traquair, Trans. Roy. Soc. Edinb. 
vol. xxx. p. 49, pi. v. figs. 5-8. 

Type. Eish ; Geological Survey of Scotland. 

General form and proportions as in the type species. Head and 
opercular bones ornamented with sharp, tortuous, and often 



432 ACTIXOPTERYGII. 

reticulating ridges. Scales marked with few prominent straight 
ridges, almost directly transverse, and terminating in acute denti- 
culations on the hinder margin ; also with few fine vertical 
striations close to and parallel with the anterior margin of the 
exposed area. 

Form. 4' Loc. Calciferous Sandstones (Cemeni>stone Group) : 
Eskdale, Dumfriesshire. 

P. 4069. Three well-preserved specimens. Purchased, 18S3. 

P. 5980. Specimen wanting paired fins. Purchased, 1889. 

The three species defined below are now assigned by Traquair 
(Ann. Mag. Nat. Hist. [6] vol. vi. 1890, p. 493) to a distinct genus, 
Mesopoma, " on account of the more typically Paheoniscid con- 
figuration of their facial bones." As, however, " the dentition is 
not yet ascertained in any of these forms, it seems also somewhat 
premature to proceed to the splitting of genera upon these dis- 
tinctions " (Trans. Roy. Soc. Edinb. vol. xxx. p. 47). 

Canobius pulchellus, Traquair. 

1881. Canobius pulchellus, R. H. Traquair, Trans. Roy. Soc. Edinb. 

vol. xxx. p. 51, pi. v. figs. 9-13. 
1890. Mesopoma pulchellum, R. H. Traquair, Ann. Mag. Nat. Hist. [6] 

vol. vi. p. 493. 

Type. Fishes ; Geological Survey of Scotland. 

Length of head and opercular apparatus almost equal to the 
maximum depth of the trunk, which is contained slightly more 
than four and a half times in the total length. Cranial roof-bones 
tuberculated ; facial bones ornamented with delicate ridges, usually 
flexuous, sometimes passing into tubercles. Scales ornamented 
with a few vertical ridges close to and parallel with the anterior 
margin, each reflexed below, and becoming directed backwards 
parallel to the inferior margin, while the remaining postero-superior 
area is occupied with ridges nearly parallel with the upper margin 
and terminating at the posterior border in denticulations. 

Form. Sf Loc. Calciferous Sandstones (Cement-stone Group) : 
Eskdale, Dumfriesshire. 

P. 4067. Specimen showing portions of all the fins except the 
pectorals. Purchased, 1883. 



PAL^EONISCIDJi:. 433 

Canobius politus, Traquair. 

1881. Canobius politus, K. H. Traquair, Trans. Roy. Soc. Edinb. 

vol. xxx. p. o3, pi. v. figs. 14-16. 
1890. Mesopoma politum, R. II. Traquair, Anu. Mag. Nat. Hist. [0] 

vol. vi. p. 493. 

Type. Imperfect fish ; Geological Survey of Scotland. 

General form and proportions as in C. pulchellus. Cranial roof- 
bones ornamented with coarse ruga?, more or less subdivided into 
elongated tubercles; facial bones striated. Scales very feebly 
ornamented with transverse, somewhat oblique ridges, in part 
terminating at the hinder border in denticulations ; dorsal ridge- 
scales comparatively small. 

Form. § Loc. Calciferous Sandstones (Cement-stone Group) : 
Eskdale, Dumfriesshire. 

P. 4070. Two specimens. Purchased, 1883. 



Canobius macrocephalus (Traquair). 

1890. Rhadinichthys macrocephalus, R. H. Traquair, Proc. Roy. Soc. 

Edinb. vol. xvii. p. 398. 
1890. Mesopoma macrocephalum, R. H. Traquair, Ann. Mag. Nat. Hist. 

[6] vol. vi. p. 493. 

Type. Fish ; collection of Dr. R. H. Traquair. 

Trunk comparatively slender, the head with opercular apparatus 
occupying somewhat less than one quarter of the total length. 
Head-bones striated, the stride upon the cranial roof being wavy 
and irregular, sometimes subdivided into tubercles. Scales feebly 
ornamented with oblique parallel ridges, terminating in denticu- 
lations at the hinder border; dorsal ridge-scales comparatively 
small. 

Form. Sf Log. Calciferous Sandstones ; Midlothian. 

41123. Specimen wanting the dorsal and pectoral fins ; locality 
unknown. Bryson Coll. 

Some doubtful fragmentary specimens from the Calciferous Sand- 
stones (Cement-stone Group) of Blackadder Water, near Dunse, 
Berwickshire, are named Canobius obscurus, R. H. Traquair, Trans. 
Roy. Soc. Edinb. vol. xxx. (1881), p. 68. [Geol. Survey of Scotland, 
Edinburgh.] 

PAKT II. 2 P 



4;U ACTIXOPIKRYGIl. 

Genus GONATODUS, Traquair. 

[Quart. Journ. Geol. Soc. vol. xxxiii. 1877, p. 555. ] 

Syu. Microconodus, R. H. Traquair, Ganoid Fishes Brit. Carb. Form. 
(Pal. Soc. 1877), p. 12 (name only). 

Trunk fusiform. Mandibular suspensorium slightly oblique ; 
teeth robust, styliform, more or less bent, forming a single, regular, 
close series on the margin of each jaw. Fins well developed, 
consisting of numerous robust, closely-jointed rays, distally branch- 
ing: fulcra small. Base of pelvic fins short; dorsal and anal fins 
triangular, the former arising somewhat in advance of the latter ; 
caudal fin forked. Scales large, smooth or feebly ornamented. 

Gonatodus pun c tat us ( Agassi z). 

1835. Amblypterus punctatus, L. Agassiz, Poiss, Foss. vol. ii. pt. i. 

p. 109, pi. iv. c. fig. 4 (non figs. 3 ; 5-8). 
(?) 1872. Amblypterus anconocechmodus, R. Walker, Trans. Edinb. 

Geol. Soc. vol. ii. pt. i. p. 119, with plate. 
1877. Gonatodus punctatus, R. H. Traquair, Quart. Journ. Geol. Soc. 

vol. xxxiii. p. 555, and Proc. Roy. Soc. Edinb. vol. ix. p. 265, 

and Ganoid Fishes Brit. Carb. Form. (Pal. Soc), pi. ii. figs. 4, 5. 
1890. Gonatodus punctatus, R. H. Traquair, Proc. Roy. Soc. Edinb. 

vol. xvii. p. 391. 

Type, Imperfect fish : Edinburgh Museum. 

The t3 T pe species, attaining a length of about 0-16. Maximum 
depth of trunk contained about three and a half times in the 
total length. Head and opercular apparatus small, triangular, 
occupying about one-fifth, of the total length ; external bones with 
sparse stria tions, often interrupted, those of the operculum and 
suboperculum transverse or obliquely directed downwards ; dentition 
consisting of acutely pointed teeth, each inclined first a little 
inwards, then bent outwards at an obtuse angle, with the apex 
finally erect. Pelvic fins arising nearer to the anal than to the 
pectorals. Scales very large, ornamented with close, transverse, 
and partly concentric, striations, becoming feeble or absent in the 
caudal region : hinder border delicately serrated. 

Form. 6f Log. Calciferous Sandstone Series : Midlothian and 
Fifeshire. 

P. 842 Well-preserved specimen, in counterpart, wanting the 
pectoral fins and part of the caudal ; Wardie. near Edin- 
burgh. Egerton Coll. 



PAUEONISCmffi. 435 

P. 3444. Much crushed specimen, displaying the pectoral fin, the 
ornamentation of some of the scales, head, and opercular 
bones, and the relatively large size of the operculum ; 
Wardie. Enuishillen Coll. 

42081. Hinder portion of maxilla ; Anstruthcr, Fifeshire. 

Purchased, 1870. 



Gonatodus macrolepis, Traquair. 

[Plate XVI. fig. 8.] 

1877. Gonatodus macrolepis, R. H. Traquair, Quart. Journ. Geol. Soc. 
vol. xxxiii. p. 556, and Proc. Roy. Soc. Edinb. vol. ix. p. 271. 

Type. Fish ; Edinburgh Museum. 

Trunk somewhat more elongated than in the type species, the 
maximum depth contained not less than four times in the total 
length. Head and opercular bones striated, the striae more or less 
interrupted and branching on the cranial roof and facial bones ; 
teeth large and obtusely pointed, nearly equal in both jaws. Scales 
very large, almost or entirely smooth ; those of the anterior part of 
the flank with feeble traces of striae close to and parallel with the 
anterior and inferior margins, and the hinder border delicately 
serrated. 

Form. Sf Log. Carboniferous Limestone (Blackband Ironstone) : 
Gilmerton, near Edinburgh, and (?) Possil, near Glasgow. 

P. 843, P. 843 a. Two typical specimens, with displaced squa- 
mation, showing portions of all the fins, and the first also 
exhibiting some of the teeth of both jaws ; Gilmerton. 
The dentition is shown, of four times the natural size, in 
PI. XVI. fig. 8. Egerton Coll. 

P. 3441. Much crushed specimen measuring 0'18 in length ; Gil- 
merton. Ennishillen Coll. 



Gonatodus parvidens, Traquair. 

[Plate XVI. fig. 7.] 

1882. Gonatodus parvidens, R. H. Traquair, Geol. Mag. T2] vol. ix. 
p. 546. 

Type. Fish ; Edinburgh Museum. 

Maximum depth of trunk contained somewhat less than four 
times in bhe total length. Head and opercular bones ornamented 

2f2 



436 ACriNOPTEKYGIl. 

with striae passing into rounded, elongated tuberculations on the 
cranial roof ; teeth of relatively small size on the maxilla. Scales 
nearly smooth, those of the anterior part of the flanks with few, 
irregular, delicate rugae close to and parallel with the anterior and 
inferior borders, and sparse pittings on the rest of the exposed 
surface ; hinder border not serrated. 

Form. <$f Loc. Middle Carboniferous Limestone (Edge-Coal 
Series) : Midlothian and Fifeshire. Carboniferous Limestone : 
Lanarkshire. 

P. 3443. Well-preserved specimen displaying all the fins, shown, of 
the natural size, in PI. XVI. fig. 7 ; Wallyford, near 
Edinburgh. The head exhibits the dorso-lateral aspect, 
and the bones are seen only as impressions of their 
external surface. The fins consist of broad, longitudinally 
ribbed rays, closely articulated and distally branching : 
and there are prominent fulcra. The pelvic fins are some- 
what inferior in size to the pectorals, and even the 
foremost rays of the latter are distinctly articulated. The 
dorsal and anal fins are about equal in size, and the latter 
arises opposite the hindermost rays of the former. The 
upper lobe of the tail is wanting distally, but the caudal 
fin is well preserved and exhibits its bifurcation. Except 
upon the upper caudal lobe, the scales are all displaced, 
but their general proportions are recognizable. 

Enniskillen Coll. 

P. 839, P. 1008. Four specimens ; Lochgelly, Fifeshire. 

Egerton Coll. 

P. 3434, P. 3442. Four specimens : Lochgelly. Enniskillen Coll. 

V. 4799. Imperfect fish ; Blackband, Fossil, near Glasgow. 

Armstrong Coll.— Transfen*ed from Edinburgh Museum, 1884. 

The following species are of uncertain generic position : — 
Gonatodus brainerdi, J. S. Newberry, Palseoz. Fishes IS". America 
(Mon. U. S. Geol. Surv. no. xvi. 1889), p. 125, pi. xxxiv. 
figs. 1,2: Palceoniscus brainardi, J. S. Newberry, Amer. 
Journ. Sci. [2] vol. xxxiv. (1862), p. 78 (name only) : 
Palceoniscus brainerdi, J. S. Newberry (ex Thomas), 
Eep. Geol. Surv. Ohio, vol. i. pt. ii. (1873), p. 346.— 
Berea Grit (Lower Carboniferous); Ohio. [Columbia 
College, New York.] 
Gonatodus molyneuxi, R. H. Traquair, Geol. Mag. [3] vol. v. 



PALJEOITCSCID^. 437 

(1888), p. 252 ; J. Ward, Trans. N". Staffs. Inst. Mining 
Engim vol, x. (1890), p. 178, pl.vi. fig. 11 : Microconodus 
molyneuxi, R. H. Traquair, Ganoid Fishes Brit. Carb. Form. 
(Pal. Soc. 1877), p. 33 (name only). — Coal-Measures 
(Deep-mine Ironstone Shale) ; Longton. [Collection of 
J. Ward, Esq.] 
Gonatodus (?) toittiezi, L. G. de Koninck, Faune Calc. Carb. Belg. 
pt. i. (1878), p. 11, pi. i. figs. 1, 2 : Palaoniscus, P. J. Van 
Beneden, Bull. Acad. Roy. Sci. Belg. [2] vol. xxxi. (1871), 
p. 515. — Upper Carboniferous Limestone ; Yiesville, Bel- 
gium. [Caudal and posterior abdominal region : University 
of Louvain.] 

The following genus and species is stated to differ only from 
Gonatodus in the downward extension of the posterior expanded 
portion of the maxilla, and in the relatively large size of the 
splenial teeth : — 

Drydenius insignis, R. H. Traquair, Proc. Roy. Soc. Edinb. vol. 
xvii. (1890), p. 399. — Carboniferous Limestone (Black- 
band Ironstone) ; near Edinburgh. [Imperfect fish ; 
Edinburgh Museum.] 

Genus AMBLYPTERUS, Agassiz. 
[Poiss. Foss. vol. ii. pt. i. 1833, pp. 3, 28.] 
Syn. Leiolepis, F. Goldenburg, Fauna Saraepontana Fossilis, 1873, p. 5. 

Trunk deeply fusiform : mandibular suspensorium only slightly 
oblique ; teeth minute. Fins large or of moderate size, with 
minute fulcra, the rays distally bifurcating ; dorsal partly in advance 
of, partly opposing the anal ; caudal fin powerful. Scales smooth, 
except sometimes in the anterior portion of the abdominal region, 
where they are more or less striated in their hinder half and serrated. 

This genus is adopted as amended by Troschel and Traquair. 
The species placed first in Agassiz's description (Palceoniscum macro- 
pterum of Bronn) does not agree with the published diagnosis in the 
nature of its dentition, and Amblypterus latus is thus regarded as 
the type species. The striking resemblance between the scales 
of this fish and those of the Palaeoniscidse of Autun now assigned to 
Amblypterus, was already pointed out by Agassiz, torn. cit. p. 38. 

Amblypterus latus, Agassiz. 

1833. Amblypterus latus, L. Agassiz, Poiss. Foss. vol. ii. pt. i. pp. 4, 37, 
pi. iv. figs. 2-6. 



438 ACTTNOPTERTGTT. 

1833. Amblypterus lateralis, L. Agassiz, ibid. pp. 4, 39, pi. iv. figs. 1, 

7-9. [Strassburg Museum.] 
1857. Amblypterus latus, F. H. Troschel, Verhandl. naturh. Verein. 

preuss. Rheinlande u. Westphalens, p. 13, pi. ii. fig. 17. 
1877. Amblypterus lotus, ~R. H. Traquair, Quart. Journ. Geol. Soc. vol. 

xxxiii. p. 552, and Ganoid Fishes Brit. Carb. Form. (Pal. Soc), 

pi. ii. fig. 1. 
1877. Amblypterus lateralis, R. H. Traquair, Quart. Journ. Geol. Soc. 

vol. xxxiii. p. 552. 

Type. Nearly complete fishes ; Strassburg Museum. 

The type species. Trunk regularly fusiform, the caudal pedicle 
being short and robust; dorsal contour much arched, and maximum 
depth in advance of the dorsal fin contained slightly more than three 
times in the total length. Head and opercular apparatus small, 
scarcely occupying one quarter of the total length ; external bones 
striated. Fins relatively large, the pelvic pair smaller than the 
pectorals, arising midway between the latter and the anal ; dorsal 
and anal fins longer than deep, the dorsal arising behind the middle 
point of the back, and the anal opposed to its hinder two thirds. 
Scales large and smooth, those of the middle of the flank not mnch 
deeper than broad. 

The sole differences between this species and the so-called A. 
lateralis seem to the present writer to be due to differences of age 
and the state of preservation. There are sparse striations upon the 
head-bones of all well-preserved specimens, and no constant 
difference in the proportions of the scales can be observed in the 
collection recorded below. 

Form. Sf Log. Lower Permian : Rhenish Prussia. 

22658. Crushed remains of an adult individual, about 0-18 in length, 
in counterpart ; Lebach. Purchased, 1848. 

22658 a. Well-preserved specimen, in counterpart, showing the 
subdivision of each series of scales at the base of the 
dorsal fin into two series ; Lebach. Purchased, 1848. 

29006. A fine example in counterpart, measuring 016 from the 
extremity of the snout to the base of the upper caudal 
lobe ; Lebach. The squamation aud portions of the fins 
are well shown. Purchased, 1859. 

P. 979, P. 3458. Two well-preserved specimens in counterpart, and 
the greater portion of a large individual with traces of 
the fine dentition ; Lebach. 

Egerton Sf EnnisTcillen Colls. 



PALJEONISCrDJE. 430 

15415, 15415 a. Two imperfect specimens in counterpart, the first 
about 0-11 in total length and displaying all the fins 
except the extremity of the caudal ; Borschweiler and 
Lebach. Purchased, 1843. 

P. 978. Imperfectly preserved small individual ; Borschweiler. 

Egerton Coll. 

32577, 36128. Two small specimens, the first in counterpart; 
Lebach. Purchased, 1857, I860. 

P. 359, P. 979 a. Two small specimens, the second labelled by 
Agassiz; Lebach. Egerton Coll. 

P. 980, P. 3459. Two small specimens, in counterpart, one half of 
the second labelled A. lateralis, and the other half both 
lotus and lateralis, in Agassiz's handwriting ; Lebach. 

Egerton 8r EnnisTcillen Colls. 

P. 3459 a. Small imperfect specimen, in counterpart, labelled A. 
lateralis by Agassiz ; Lebach. EnnisJcillen Coll. 

28487. Well-preserved remains of a very small individual, in 
counterpart ; Saarbruck. Purchased, 1853. 



Amblypterus traquairi, sp. nov. 
[Plate XV. fig. 2.] 

Type. Imperfectly preserved fish ; British Museum. 

Trunk regularly fusiform, the caudal pedicle robust, and the 
dorsal contour not much arched ; maximum depth contained about 
four times in the total length. Head and opercular apparatus 
occupying one quarter of the total length ; external bones coarsely 
striated. Fins relatively large, the pelvic pair scarcely smaller 
than the pectorals, arising midway between the latter and the anal ; 
dorsal and anal fins longer than deep, the dorsal arising at about 
the middle point of the back, and the anal opposed to its hinder 
two thirds. Scales relatively large, apparently all smooth. 

Form. Sf Loc. Lower Permian : Rhenish Prussia. 

P. 994, P. 3457. Type specimen 0*2 in length, preserved in coun- 
terpart, and shown, about three-quarters nat. size, in 
PI. XV. fig. 2 ; Lebach. The bones of the head are much 
scattered, but the outlines of some are distinct. 

Egerton Sf EnnisTcillen Colls. 



440 ACT1N0PTERYGTI.. 

P. 994 a, P. 3457 a. Smaller individual, in counterpart, wanting 
part of the head and the extremity of the tail ; Lehach. 

Efjerton 4' Ennishillen Colls. 

P. 980 a, P. 3459 a. Small specimen, in counterpart, obliquely 
crushed, and labelled Amblypterus lateralis by Agassiz ; 
Lebach. Egerton $ Ennishillen Colls. 



Amblypterus duvemoyi (Agassiz). 

1833. Palceoniscus duvernoy, L. Agassiz, Poiss. Foss. vol. ii. pt. i. pp. 4, 
45, 103, pi. vii. 

1834. Palceoniscus vratislaviensis, L. Agassiz, ibid. p. 60, pi. x. figs. 1, 
2,4-6. 

1834. Palceoniscus lepidurus, L. Agassiz, ibid. p. 64, pi. x. figs. 3, 7, 8, 9. 
1848. Amblypterus duvernoy, C. G. Giebel, Fauna der Vorwelt, Fische, 

p. 252. 
1848. Palceoniscus vratislaviensis, C. G. Giebel, ibid. p. 247. 
1851. Palceoniscus gibbus, F. H. Troschel, Verhandl. naturh. Verein 

preuss. Rheinlande u. AYestphalens, p. 523, pi. ix. 
1851. Palceoniscus dimidiatus, F. H. Troschel, ibid. p. 528, pi. x. 
(?) 1851. Palceoniscus tenuicauda, F. H. Troschel, ibid, p. 532, pi. xi. 
(?) 1851. Palceoniscus elongatus, F. H. Troschel, ibid. p. 536, pi. xii. 
1851. Palceoniscus opisthopterus, F. H. Troschel, ibid. p. 538, pi. xiii. 
1857. Palceoniscus duvemoyi, F. H. Troschel, ibid. p. 16. 
1861. Palceoniscus rohani, J. J. Heckel, Denkschr. k. Akad. YYiss., 

rnath.-naturw. CI. vol. xix. p. 51, pis. i.-iii. [Koyal Bohemian 

Museum, Prague.] 
1861. Palceoniscus obliquus, J. J. Heckel, ibid. p. 56, pi. v. [Ibid.] 
1861. Palceoniscus caudatus, J. J. Heckel, ibid. p. 58, pi. vi. [Ibid.1 
1861. Palceoniscus vratislaviensis and lepidurus, H. B. Geinitz, Dyas, 

pp. 18, 19. 
1861. Palceoniscus blainvillei, H. B. Geinitz (errore), ibid, p. 19, pi. ix. 

fig. 3. 
1864. Palceoniscus vratislaviensis, E. Weiss, Zeitschr. deutsch. geol. 

Gesell. vol. xvi. p. 274, woodcut. 
1877. Amblypterus duvemoyi, E, H. Traquair, Quart. Journ. Geol. Soc. 

vol. xxxiii. p. 558. 
1877. Amblypterus wratislaviensis, R. H. Traquair, ibid. p. 558. 
1877. Amblypterus lepidurus, dimidiatus, elongatus, tenuicauda, gibbus, 

opisthopterus, rolianni, obliquus, and caudatus, R. H. Traquair, ibid. 

p. 558. 

Type. Two nearly complete fishes ; Palaeontological Museum, 
Munich, and olim H. G. Bronn Collection. 

Trunk deep in the abdominal region, and the caudal pedicle 
produced ; the back much arched in advance of the dorsal fin, the 



P ALTEON LSCTDJE. 441 

greatest depth of the trunk equalling about one quarter of the total 
length of the fish. Head and opercular apparatus small, occupying 
about one-fifth of the total length; external bones striated, the 
striae upon the cranial roof being coarse, irregular, and more or 
less subdivided. Paired fins small, the pelvic pair placed slightly 
nearer to the anal than to the pectorals ; dorsal and anal fins equal 
in size, triangular and short-based, the dorsal arising behind the 
middle of the back, and the anal opposed to its hinder half. Scales 
arge, those of the middle of the flank somewhat deeper than broad ; 
a few series immediately behind the clavicle exhibiting fine posterior 
flutings and denticulations. 

As pointed out by Giebel and Traquair, this species is truly re- 
ferable to Amblypterus ; and the other so-called species of Palceo- 
niscus, here regarded as synonyms, have also been assigned to 
Amblypterus by Traquair. The type specimens were obtained from 
the black shales of Kreuznach, and it appears to the present writer 
that the various forms named by Troschel from the same formation 
and locality owe their supposed distinctive features merely to dif- 
ferences in crushing and state of preservation. The latter series 
has already been identified with "Paloeoniscus " vratislaviensis by 
Weiss, who gives an elaborate table of measurements to show the 
great variation in the proportions of typical examples of P. vratis- 
laviensis from Ruppersdorf, Bohemia. As a rule the last-mentioned 
specimens do not attain so large a size as those from Kreuznach ; 
but there are intermediate forms, and the examples from Miinster 
Appel assigned by Agassiz to P. cluvernoyi are almost equally 
small. 

The so-called Palceoniscus minutus, Agassiz (Poiss. Foss. vol. ii. 
pt. i. pp. 4, 47, pi. viii. figs. 1-3), from Miinster Appel, of which 
the type is in the Strassburg Museum, is probably the young of 
this species. It is provisionally assigned to Awiblypterus by 
Traquair, Quart. Journ. Geol. Soc. vol. xxxiii. p. 558. 

A very large imperfect fish from the Lower Permian of Semil, 
Bohemia, described under the name of Palceoniscus luridus (J. J. 
Heckel, Denkschr. k. Akad. Wiss., math.-naturw. CI. vol. xix. 1861, 
p. 54, pi. iv.), is also difficultly distinguishable from Amblypterus 
duvemoyi ; the specimen is in the Royal Bohemian Museum, 
Prague. 

Form. <$f Log. Lower Permian : Rhenish Bavaria and Bohemia. 

37775-76. Two typical large specimens in black shale, of unknown 
locality ; one larger than Agassiz's second type specimen, 
and the other exhibiting well-preserved scales and median 
fins. Purchased, 1863. 



142 ACTTXOVTEHTGTI. 

P. 981. Small imperfect specimen, labelled Palceoniscus gibbvs, 
Troschel ; Sobernheim, near Kreuznach. Egerton Coll. 

P. 3467. Similar specimen ; Sobernheim. Enniskillen Col J. 

P. 3464. More satisfactorily preserved fish, of the form named T. 
dimidiatus, Troschel ; Sobernheim. Enniskillen Coll. 

P. 983. An imperfectly preserved individual, extended during fos- 
silization, of the form named P. tenuicauda, Troschel ; 
Sobernheim. Egerton Coll. 

P. 982. Small specimen, resembling the so-called P. opistliopterus, 
Troschel ; Sobernheim. Egerton Coll. 

P. 985 a. Somewhat smaller but similar specimen, labelled P. duver- 
noyi by Agassiz ; Moersfeld. Egerton Coll. 

20665-66. Two small specimens, one wanting head ; Moersfeld. 

Purchased, 1846. 

28615. Small individual in similar matrix ; Moersfeld. 

Dixon Coll. 

P. 984-5. Seven small examples : Moersfeld and Zweibriicken, near 
Miinster Appel. Some of these and the next specimens 
are labelled by Agassiz, and are noticed in the Poiss. 
Foss. vol. ii. pt. i. p. 103. Egerton Coll. 

P. 3465-66, P. 4352. Four similar specimens : Moersfeld and 
Zweibriicken. Enniskillen Coll. 

P. 987. Very young individual, wanting head ; Miinster Appel. 

Egerton Coll. 

20663-64. Three imperfect examples of the trunk, wanting the 
head, two being as large as the first of the type specimens ; 
Ottendorf, Bohemia. Purchased, 1840. 

P.. 988-9. Two small specimens, one in a very similar state of pre- 
servation to the so-called P. lepidv.vvs, Agassiz ; Otten- 
dorf. Egerton Coll. 

P. 3471. Typical specimen : Oelberg, near Braunau, Bohemia. 

Enniskillen Coll. 

P. 3471 a. Smaller example ; said to have been obtained from 
Braunau. Enniskillen Coll. 

877. Trunk of typical "Palceoniscus vratislaviensis" wanting head; 
Ruppersdorf, Bohemia. Purchased, 1837. 



PAL.V.O'NrTPCrD.'E. 



443 



1229. Similar specimen, with fragments of the head ; Euppersdorf. 

Purchased, 1837. 

20662. Six small examples, variously crushed : Euppersdorf. 

Purchased, 1846. 

23405. Imperfect fish, shortened by crushing ; Euppersdorf. 

Purchased, 1849. 

36591. Trunk, wanting head ; Euppersdorf. Dixon Coll. 

38158. Six specimens, three being only slightly crushed ; Euppers- 
dorf. 

Presented by Sir Roderick I. Murchison, K.G.B., 1864. 

P. 991. Three specimens, one originally measuring about 0*16 in 
length and identical with the Ehenish examples in form 
and proportions ; Euppersdorf. Egerton Coll. 

P. 6289. Elongated specimen ; Euppersdorf. Purchased. 

P. 3470. Tour small fishes, two appearing relatively slender ; Eup- 
persdorf. Enniskillen Coll. 

38158 a. Three small specimens ; Euppersdorf. 

Presented by Sir Roderick I. Murchison, K.C.B., 1864. 



Amblypterus beaumonti (Egerton). 

1850. Palceoniscus beaumonti, Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. vi. p. 6, pi. i. figs. 5, 6. 
1877. Amblypterus beaumonti, E. H. Traquair, ibid. vol. xxxiii. p. 558. 

Type. Imperfect head and trunk, wanting fins ; British Museum. 

A large species, attaining a length of not less than 0'35. Trunk 
regularly fusiform, the dorsal margin arched in advance of the 
dorsal fin, and the maximum depth contained about four times in 
the total length. Head with opercular apparatus occupying some- 
what less than one quarter of the total length ; external bones 
marked with coarse vermiculating rugae. Pelvic fins nearly as 
large as the pectorals, arising midway between the latter and the 
anal ; dorsal arising about the middle of the back, immediately 
behind the pelvic fins, relatively small, short-based, and triangular, 
almost completely in advance of the anal, which equals it in size 
and form. Scales large, those of the middle of the flank slightly 
deeper than broad ; dorso-lateral scales smooth, with non-serrated 
posterior margins ; ventro-lateral scales with few posterior serra- 



444 ACTTNOPTHRYGTT. 

tious, those immediately behind the pectoral arch also marked with 
short oblique striae terminating in the serrations. 
Form. $• Loc. Lower Permian : Autun, France. 

P. 3418. Type specimen. Ennislillen Coll. 

P. 3419. Well-preserved small trunk, with fins, noticed by Egerton, 
loc. cit. Ennislillen Coll. 

P. 986, P. 3417. Partially scattered remains of large trunk and 
median fins, in counterpart. Egerton § Ennislillen Colls. 

P. 3417 a. Smaller imperfect trunk and fins. EnnishiUen Coll. 

Amblypterus decorus (Egerton). 

1850. Palceoniscus decorus, Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. vi. p. 7, pi. ii. 
1877. Amblypterus decorus, E. H. Traquair, ibid. vol. xxxiii. p. 558. 

Type. Eish with imperfect head ; British Museum. 

A large species, attaining a length of not less than 0-25. Form 
and proportions of head, trunk, and fins as in A. beaumonti; ex- 
ternal bones similarly ornamented with vermiculating rugas. Scales 
all smooth, without posterior serrations, except feeble traces in the 
anterior ventro-lateral region : principal scales of flank scarcely 
deeper than broad. 

Form. $- Loc. Coal-Measures : Commentry, Allier, France ; Harz 
Mts. 

P. 607, P. 3420. Type specimen, being a fish wanting the greater 
portion of the caudal region, but completely shown in the 
counterpart impression ; Commentry. 

Egerton § Ennislillen Colls. 

28293. Dorsal half of abdominal region and the caudal pedicle ; 
Commentry. Purchased, 1851. 

P. 3422. Imperfectly preserved fish wanting the extremity of the 
tail, compared with this species by Egerton, loc. cit. p. 7 ; 
Ilfeld, Harz. Ennislillen Coll. 



Amblypterus arcuatus (Egerton). 

1850. Palceoniscus arcuatus, Sir P. Egerton, Quart. Journ. Geol. Soc. 

vol. vi. p. 7, pi. i. fig. 1. 
1877. Amblypterus arcuatus, B. H. Traquair, ibid. vol. xxxiii. p. 558. 

Type. Head and abdominal region ; British Museum. 



rALJBONlSClD.fi. 



445 



An imperfectly known species of moderate size. Trunk robust ; 
dorsal margin gently arched in advance of dorsal fin. Head-bones 
marked with coarse vermiculating ridges; teeth of mandible in 
regular close series, very slender. Dorsal fin arising opposite the 
hinder portion of the pelvic pair. Scales relatively smaller and 
thicker than those of A. decorus, scarcely deeper than broad on the 
middle of the Hank, those of the anterior ventro -lateral region 
feebly crenulated and serrated. 

Form. Sf Loc. Permian : Prussia. 

P. 3461. Type specimen, displaying the mandibular teeth ; Gold- 
lauter. EnnisJcillen Coll. 

P. 3462. More imperfect, larger head and abdominal region ; Gold- 
lauter. Ennishillen Coll. 



Amblypterus reussi (Heckel). 

18(31. Palcconiscus reussii, J. J. Heckel, Denkschr. k. Akad. Wiss., 

math.-naturw. CI. vol. xix. p. 61, pi. vii. 
1877. Amblypterus reussii, R. H. Traquair, Quart. Joiirn. Geol. Soe. 

vol. xxxiii. p. 558. 

Type,. Nearly complete fish ; Eoyal Bohemian Museum, Prague. 

Trunk short and deep, the maximum depth in advance of the 
dorsal fin contained about three and a half times in the total length. 
Head and opercular apparatus occupying less than one quarter of 
the total length ; external bones marked with fine striae and ruga?. 
Pelvic fins well developed, inserted halfway between the pectorals 
and the anal ; dorsal arising behind the middle of the back, high, 
triangular, and short-based, directly opposed to the slightly smaller 
anal. Scales large, those of the middle of the flank deeper than 
broad ; all smooth, except two or three anterior series, which 
exhibit delicate fiutings and crenulations at the free margin. 

Form. $ Loc. Lower Permian : Semil, Bohemia. 

Not represented in the Collection. 

Amblypterus blainvillei (Agassiz). 

1818. Palcsothrissum incequilobum, H. D. de Blainville, Nouv. Diet. 
d'Hist. Nat. vol. xxvii. p. 321 (imperfectly defined). 

1818. Palceothrissum parviwi, H. D. de Blainville, ibid. p. 321 (imper- 
fectly defined). 

1833. Palceoniscus blainvillei, L. Agassiz, Poiss. Foss. vol. ii. pt. i. pp. 4. 
48, pi. v. 



44(> ACTlNOPTERYl'Il. 

889. Palaoniscus blainvillei, Landriot, Compte-Itendu Soc. Eduemie, 

vol. i. p. 122, pi. fig. 2. 
L877. Amblypterw (?) blainvillei, R. H. Traquair, Quart. Journ. Geol. 
Soc. vol. xxxiii. p. 558. 

7///«?. Nearly complete fishes ; Strassburg Museum. 

Trunk short and deep, the maximum depth immediately in ad- 
vance of the dorsal fin contained nearly three and a half times in 
the total length. Head and opercular apparatus relatively small, 
occupying less than one quarter of the total length ; external hones 
marked with fine striae and rugae. Pelvic fins well developed, in- 
serted halfway between the pectorals and the anal ; dorsal arising 
about the middle of the back, relatively small, short-based, and 
triangular, completely in advance of the anal, which equals it in 
size and form. Scales large, those of the middle of the flank nearly 
twice as deep as broad, all smooth and not crenulated. 

Form. $ Loc. Lower Permian ; Muse, near Autun. 

36051. Well-preserved specimen, 0*115 in length, wanting the 
extremity of the upper caudal lobe. 

Presented by S. P. Pratt, Esq., 1857. 

41908. Slab of shale with remains of several individuals. 

Purchased, 1870. 

P. 996-7. Various fragmentary specimens, some perhaps referable 
to the next species. Egerton Coll. 

P. 3469. Slab of shale with remains of three or four individuals, 
and four other specimens. EnnisJcillen Coll. 



Amblypterus voltzi (Agassiz). 

1833. Palcemiscus voltzii, L. Agassiz, Poiss. Foss. vol. ii. pt. i. pp. 5, 

55, 83, pi. vi., pi. d. fig. 1. 
1839. Palceoniscus voltzii, Landriot, Compte-Rendu Soc. Eduenne, 

vol. i. p. 122, pi. fig. 1. 
1877. Amblypterus (?) voltzii, R. H. Traquair, Quart. Journ. Geol. Soc. 

vol. xxxiii. p. 558. 

Type. Nearly complete fishes ; Strassburg Museum and Museum 
of Natural History, Paris.. 

A species closely related to A. blainvillei, but described as cha- 
racterized by its somewhat more elongated shape, the relatively 
larger size of the head and scales, and the smoothness of the oper- 
culum. 

Form. Sf Loc. Lower Permian : Muse, near Autun. 



1WL.KONISCID.E. *147 

33991-92. Small individual, wanting head, and the caudal region 
of another specimen, probably of this species. 

Presented by Sir Roderick I. Murchison, K.C.B., 1860. 

The following specimens are of the form named Palceoniscus 
angustus by Agassiz, Poiss. Poss. vol. ii. pt. i. (1833), pp. 4, 57, 
pi. ix. figs. 1-5 * ; but it is still uncertain whether they may not 
be the young of A. voltzi. They are provisionally assigned to Am- 
blypterm by Traquair, Quart. Journ. Geol. Soc. vol. xxxiii. p. 558. 

P. 990. Obscurely preserved specimen, exhibiting a short regular 
series of slender conical teeth ; Muse, near Autun. 

Egerton Coll. 

P. 3475. A more satisfactorily preserved trunk, with imperfect 
head ; Muse. Enniskillen Coll. 

The following specimens may pertain to Amblypterus, as here 
defined, but do not suffice for exact determination: — 

P. 6290. Small fish, wanting the greater part of the head arid paired 
fins ; Lower Permian, Kostialov, Bohemia. Purchased. 

P. 5564. Smaller fish, with imperfect head ; Lower Permian, 
Nyfan, Bohemia. Purchased, 1888. 

P. 995. Fish 0-125 in length, with imperfect fins ; Coal-Measures, 
Commentry, Allier, France. Egerton Coll. 

P. 1013. Imperfect larger specimen, noticed by Egerton, Quart. 
Journ. Geol. Soc. vol. vi. p. 8 ; Coal-Measures, Liege, 
Belgium. Egerton Coll. 

The following species have also been described, but there are no 
examples in the Collection : — 

Amblypterus costatus : Palceoniscus costatus, E. von Eichwald, 
Leth. Rossica, vol. i. (1860), p. 1583, pi. lv. fig. 10.— 
Permian ; Kargala, Govt, of Orenburg, Russia. 

Amblypterus gelberti, R. H. Traquair, Quart. Journ. Geol. Soc. 
vol. xxxiii. (1877), p. 558 : Palceoniscus gelberti, Goldfuss, 
Beitr. vorweltl. Fauna Steinkohlengeb. (1847), p. 17, pi. iv. 
figs. 4-6. — Lower Permian ; Heimkirchen, near Kaisers- 
lautern. [University of Bonn.] 

Amblypterus (?) nanus : Palceoniscus nanus, E. von Eichwald, Bull. 
Soc. Imp. Nat. Moscou, 1857, pt. ii. p. 350, and Leth. 

1 Specimens from the Lower Permian of Hohenelbe are also assigned to 
this species by H. B. Geinitz, Dyas, p. 20, pi. x. figs. 2, 3. 



44S VCTINOl'TERYGU. 

Rossica, vol. i. (18G0), p. 1586, pi. lv. fig. 12.— Permian ; 
Kargala. 

Amblypterus tuberculatus : Palceoniscus tuberculatum, E. von Eich- 
wald, Bull. Soc. Imp. Nat. Moscou, 1857, pt. ii. p. 349, 
and Leth. Bossica, vol. i. (1860), p. 1585, pi. lv. fig. 11. 
— Ibid. [University of St. Petersburg.] 

Some fishes from the Lower Permian of Moravia, said to be 
related to the species from France and Bohemia here assigned to 
Amblypterus, bear the undefined names of Palceoniscus katholitz- 
kianus, P. moravicus, and P. promptus (A. Rzehak, Yerhandl. k.-k. 
geol. Reichsanst. 1881, p. 79). 

The so-called Amblypterus orientalis (E. von Eichwald, Leth. 
Rossica, vol. i. 1860, p. 1588, pi. lv. fig. 15), possibly identical with 
the imperfectly defined Tetragonolepis murchisoni (G. Eischer de 
Waldheim, Bull. Soc. Imp. Nat. Moscou, 1842, p. 463), is of doubt- 
ful genus, the type specimen being a portion of squamation, with 
remains of median fins, from the Permian of Kargala, Govt, of 
Orenburg, Russia. Amblypterus ornatus, E. Emmons (Manual Geol. 
ed. 2, 1860, p. 183, fig. 161, nos. 1-3), from the Chatham Series 
of North Carolina, is also founded upon indeterminable Palaeoniscid 
scales. 

Amblypterus olfersi, L. Agassiz, Poiss. Eoss. vol. ii. pt. i. (1833), 
pp. 4, 40, from the Upper Cretaceous of Brazil, was subsequently 
recognized by the same author as referable to the Physostomous 
bony fish Bhacolepis {ibid. vol. ii. pt. ii. 1844, p. 283). 

Genus EURYLEPIS, Newberry. 

[Proc. Acad. Nat. Sci. Philad. 1857, p. 150.] 

Syn. Meoolepis, J. S. Newberry, Proc. Acad. Nat. Sci. Philad. vol. viii. 
1856, p. 96 (preoccupied). 

Trunk fusiform. Mandibular suspensorium nearly vertical ; snout 
rounded ; gape small, and teeth numerous, short, and conical. Eins 
relatively small, with delicate fulcra ; fin -rays robust, not branching, 
but merely attenuated distally. Dorsal and anal fins short-based, 
triangular-acuminate, nearly opposite, the former arising only 
slightly in advance of the latter ; caudal fin obliquely truncated or 
exhibiting very slight excavation. Scales smooth or with feeble 
ornament, often serrated ; two or more series of flank-scales not less 
than twice as deep as broad. 

The species of this genus are all of very small size, and have only 
been discovered hitherto in a thin seam of cannel-coal in the Coal- 
Measures at Linton, Ohio. 



PALJEONISCIDiE. 449 

Eurylepis tuberculata, Newberry. 

1856. Mecolepis tuberculatus, J. S. Newberry, Proc. Acad. Nat. Sci. 

Philad. vol. viii. p. 96. 
1873. Eurylepis tuberculatus, J. S. Newberry, Rep. Geol. Surv. Ohio, 

vol. i. pt. ii. p. 350, pi. xxxviii. figs. 2, 3. 

Type. Pish ; Columbia College, .New York. ■ 

The type species, attaining a maximum length of about 0*08. 
Length of head with opercular apparatus about equal to the 
maximum depth of the trunk, and occupying one-fourth of the 
total length of the fish. Cranial roof-bones ornamented with large 
rounded rugae and tuberculations, facial bones with finer corru- 
gations. Scales smooth, denticulated in the abdominal region ; 
anterior scales of principal series nearly five times as deep as broad. 

Form. Sf Loc. Coal-Measures : Linton, Ohio. 

P. 1005. Three specimens labelled by Dr. Newberry. Egerton Coll. 

P. 3449. Two specimens and one in counterpart, labelled by Dr. 
Newberry. Enniskillen Coll. 



Eurylepis granulata, Newberry. 

1856. Mecolepis yranulatus, J. S. Newberry, Proc. Acad. Nat. Sci. 

Philad. vol. viii. p. 97. 
1856. Mecolepis insculptus, J. S. Newberry, ibid. p. 97. [Columbia 

College, New York.] 
1873. Eurylepis yranulatus, J. S. Newberry, Rep. Geol. Surv. Ohio, 

vol. i. pt. ii. p. 352, pi. xxxix. fig. 5. 
1873. Eurylepis insculptus, J. S. Newberry, ibid. p. 351, pi. xxxix. 

fig. 2. 

Type. Pish ; Columbia College, New York. 

General proportions as in the type species. Cranial roof-bones 
ornamented with sharp corrugations and occasional intervening 
granulations. Scales comparatively thin, more or less rugose and 
tuberculated in the anterior part of the abdominal region, with a 
faint double waved line along the anterior margin, and fine posterior 
serrations ; foremost scales of principal lateral series about four 
times as deep as broad. 

Form. Sf Loc. Coal-Measures : Linton, Ohio. 

P. 1007. Two well-preserved specimens. Egerton Coll. 

P. 3450. Similar specimen, labelled E. yranulatus by Dr. Newberry. 

Ennis7cillen Coll. 

PART II. 2 G 



450 ACTLNOPTERYGI1. 

A form of Eurylepis, apparently distinguished from E. granulata 
merely by the extension of the scale-ornament over the caudal 
region, is named E. ornatissima, J. S. Newberry, Rep. Geol. Surv. 
Ohio, vol. i. pt. ii. (1873), p. 352, pi. xxxix. fig. 4 (= J\£ ecolepis 
oniatissimus, J. S. Newberry, Proc. Acad. Nat. Sci. Philad. vol. viii. 
1856, p. 97). Three other species are also determined as enume- 
rated below, the type specimens being nearly complete fishes in 
the Aluseum of Columbia College, New York : — 

Eurylepis corrugata, J. S. Newberry, Rep. Geol. Surv. Ohio, 
vol. i. pt. ii. (1873), p. 350, pi. xxxviii. fig. 4 : Mecolepis 
oorrugatus, J. S. Newberry, Proc. Acad. Nat. Sci. Philad. 
vol. viii. 1856, p. 96 (adopted as type of Mecolepis). 

Eurylepis (?) lineata, J. S. Newberry, ibid. 1873, p. 353, pi. 
xxxix. fig. 7 : Mecolepis lineatus, J. S. Newberry, ibid. 
1856, p. 97 : Bhadinichthys (?) lineatus, J. S. Newberry, 
Palseoz. Pishes N. America (Mon. U. S. Geol. Surv. no. xvi. 
1889), p. 228. 

Eurylepis striolata, J. S. Newberry, torn. cit. 1873, p. 355. 

The small fish from the Coal-Measures of Linton, Ohio, named 
Mecolepis serratus, J. S. Newberry (Proc. Acad. Nat. Sci. Philad. 
vol. viii. 1856, p. 97), does not appear to have been mentioned 
since the original notice. 

The following specimens appear to the present writer to be 
specifically indeterminable immature individuals : — 

P. 998. Two small fishes of the form named Eurylepis ovoidea \ 
from Linton. Egerton Coll. 

P. 1006. Three small fishes of the form named Eurylepis minima 2 , 
from Linton. Egerton Coll. 

P. 3451. Four similar specimens. EnnisJcillen Coll. 

Another genus of stout proportions, with nearly vertical sus- 
pensorium, now assigned to the Paheoniscidoe, is Benedenichthys, 
R. H. Traquair (Ami. Mag. Nat. Hist. [6] vol. vi. 1890, p. 492), 
originally defined under the pre-occupied name of Benedenius 
(Traquair, in L. G. de Koninck, Paune Calc. Carb. Belg. pt. i. 1878, 

1 J. S. Newberry, Rep. Geol. Surv. Ohio, vol. i. pt. ii. (1873), p. 351, pi. 
xxxix. fig. I : Mecolepis ovoideus, J. S. Newberry, Proc. Acad. Nat. Sci. Philad. 
vol. viii. 1856, p. 97. 

2 J. S. Newberry, ibid. 1873, p. 353, pi. xxxix. fig. 3. 



PVLJSONISCJDvE. 451 

p. 14). There are no examples in the Collection, and the following 
is the only recognized species : — 

Benedeniohthys deneensis, R. H. Traqnair, Faune Calc. Carb. Belg. 
pt. i. (1878), p. 16, pi. ii., and Trans. Roy. Soc. Edinb. 
vol. xxix. (1879), p. 354, pi. iii. fig. 17 (Benedenius) : 
PalceonisGus deneensis, P. J. Van Beneden, Bull. Acad. Roy. 
Belg. vol. xxxi. (1871), p. 512, pi. iv. — Carboniferous 
Limestone : Denee, Belgium. [Imperfect fish j University 
of Louvain.] 



Genus CHEIROLEPIS, Agassiz. 
[Poiss. Foss. vol. ii. pt. i. 1835, p. 128.] 

Trunk elongated and gradually tapering from the maximum 
depth at or immediately behind the pectoral arch. Mandibular 
suspensorium oblique; dentition consisting of an inner series of 
large, well-spaced conical teeth, with an outer series of numerous 
very small teeth ; head and opercular bones ornamented with 
striations, irregular rugae, or elongated tubercles. Fins of moderate 
size, consisting of numerous very delicate rays, articulated and 
branching; fulcra prominent, and the ridge-scales of the upper 
caudal lobe distinctly divided into two halves at the apex. Pelvic 
fins with extended base-line ; dorsal fin scarcely longer than deep, 
the anal elongated, and the former not arising in advance of the 
origin of the latter ; upper caudal lobe short and stout, the fin 
inequilobate and only slightly forked. Scales minute, relatively 
thick, and coated with ganoine, having an internal vertical rib, not 
overlapping. 

The most elaborate description of Cheirolepis, with numerous 
figures, is that of Pander, published in 1860 1 ; and additional ob- 
servations, with corrections, were subsequently contributed by 
Traqnair 2 . By Pander the genus was regarded as representing a 
peculiar family, Cheirolepidse, afterwards adopted by Huxley 3 ; but 
the researches of Traqnair seem to justify its being assigned to the 
Pala3oniscida3. 

1 0. H. Pander, Ueber die Saurodipt., Dendrodont., G-lyptolepid., u. Cheiro- 
lepid. devon. Syst. (1860), pp. 69-73. 

2 R. H. Traquair, Aim. Mag. Nat. Hist. [4] vol. xv. (1875), pp. 237-249, 
pi. xvii. 

3 T. H. Huxley, Figs. & Descrips. Brit. Organic Remains (Mem. Greol. Surv. 
1861), dec. x. pp. 38-40. 






" 



452 ACTINOPTERYGll. 

Cheirolepis trailli, Agassiz. 

1828. ' Second Garnrie Ichthyolite,' Pentland, Trans. Geol. Soc. [2] 

vol. ii. p< 364 
1835. Cheirolepis traillii, L. Agassiz, Poiss. Foss. vol. ii. pt. i. p. 130, 

pi. i. d, pi. i. e. fig. 4. 
1835. Cheirolepis uragus, L. Agassiz, ibid. p. 132, pi. i.e. figs. 1-3 l . 
1844. Cheirolejns cummingice y L. Agassiz, ibid. p. 301 (name only). 
1844. Cheirolepis cummingice, L. Agassiz, Poiss. Foss. V. G\ R. p. 45, 

pi. xii. [Forres Museum.] 
1848. Chirolepis curtus, F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. ii. 

p. 302. [Woodwardian Museum.] 
1848. Chirolepis macrocep>halus, F. M'Coy, ibid. p. 303. [Ibid.] 
1848. Chirolepis velox, F. M'Coy, ibid. p. 302. [Ibid.] 
1855. Chirolepis traillii, F. M'Coy, Brit. Palaeoz. Foss. p. 581. 
1855. Chirolepis uragus, F. M'Coy, ibid. p. 581. 
1855. Chirolepis curtus, F. M'Coy, ibid. p. 580, pi. ii. d. fig. 1. 
1855. Chirolepis macrocephalus, F. M'Coy, ibid. p. 580, pi. ii. d. fig. 3. 
1855. Chirolepis velox, F. M'Coy, ibid. p. 581, pi. ii. d. fig. 2. 
1860. Chirolepis curtus= C. cummingice, Sir P. Egerton, Quart. Journ. 

Geol. Soc. vol. xvi. p. 123. 
1860. Chirolepis macrocephalus = C. trailli, Sir P. Egerton, ibid. p. 123. 
1867. Cheirolepis trailli, J. Powrie, Geol. Mag. vol. iv. p. 152. 
1867. Cheirolepis cummingice, J. Powrie, ibid. p. 152. 
1867. Cheirolepis uragus, J. Powrie, ibid. p. 152. 
1875. Cheirolepis cummingice^ R. H. Traquair, Ann. Mag. Nat. Hist. [4] 

vol. xv. p. 240, pi. xvii. 
1888. Cheirolepis trailli, R. H. Traquair, Geol. Mag. [3] vol. v. p. 517. 
1890. Cheirolepis trailli, R. H. Traquair, Ann. Mag. Nat. Hist. [6] 

vol. vi. p. 485. 

Type. Imperfect fishes ; olim T. S. Traill Collection. 

The type species, attaining a length of about 0*35. Maximum 
depth of trunk contained about five and a half times in the total 
length. Head slightly longer than deep, the head with opercular 
apparatus occupying one-fifth of the total length ; facial and oper- 
cular bones coarsely striated, the striae on the circumorbitals 
radiating, those on the expansion of the maxilla chiefly horizontal, 
though somewhat reticulated behind, and those of the operculum 
obliquely directed downwards and backwards. Pelvic fins relatively 
low and small, arising somewhat nearer to the anal than to the 
pectorals ; dorsal and anal fins equally elevated, the former about 
two-thirds as long as the latter, and arising slightly behind the 
origin of this fin ; all the larger joints of the fin-rays sculptured 

1 Under this name fragments from near Pawlowsk, Govt, of St. Petersburg, 
are described by E. von Eichwald, Letb. Eossica, vol. i. (1860), p. 1575, pi. lvii. 
fig. 21. 



pal.eoniscid.*:. 453 

with fine marginal pectinations. Scales very gmall, with fine, 
short, marginal pectinations in their antero-superior portion. 

Form. $• Loc. Lower Old Red Sandstone : Orkney, Caithness, 
Ross-shire, Nairnshire, Cromarty, and Banffshire. 

(i.) Orkney (typical 0. trailli). 

35045. Obscurely preserved fish, with impressions of fins, the bones 
and scales converted into a shining bituminous substance ; 
Stromness. Purchased, 1860. 

39187. Smaller example with distinct remains of dentition and 
ornamented squamation. Bowerbank Coll. 

40969. Specimen 0-26 in length, similar to the first in state of 
preservation ; Stromness. Purchased, 1867. 

P. 171-5. Five similarly-preserved specimens, the third only 0*17 
in length and in counterpart. Purchased, 1881. 

P. 1367. Two similar specimens showing the greater portion of the 
squamation and fins in impression; Belyacreugh. 

Egerton Coll, 

(ii.) Ross-shire. 

41731. Imperfect trunk with well-preserved squamation and 
remains of the fins ; Glen Roy. Purchased, 1869. 

P. 6077. Remains of the head, pectoral arch, and abdominal region ; 
probably from Edderton, near Tain. The coarsely rugose 
ornament of the clavicle and supraclavicle is displayed. 

Presented by F. Harford, Esq., 1889. 

P. 1174. Caudal region, imperfectly preserved ; Edderton. 

Egerton Coll. 

(iii.) Lethen Bar, Nairnshire (typical C. cummingice). 

49182. Imperfectly-preserved fish, in counterpart, 0-25 in length, 
showing all the fins. Purchased, 1878. 

49193. Similar specimens displaying some of the teeth and branchio- 
stegal rays. Purchased, 1878. 

P. 2073, P. 3402. Similar specimen, in counterpart, 0-3 in length, 
with nearly complete caudal fin, showing its inequilobate 
form and slightly excavated posterior border. 

Egerton Sc Enniskillen Colls. 



454 ACTTNOrTFRYOTT. 

P. 3403. Head and much distorted trunk, ventral aspect. The jaws 
and branchiostegal rays are well shown, and are described 
and figured by Traquair, loc. cit. (1875), p. 246, pi. xvii. 
fig. 1. EnnisTciUen Coll. 

41725, P. 5597. Imperfect head and abdominal region, ventral 
aspect, in counterpart. The left maxilla, the mandible, 
branchiostegal rays, infraclavicles, and the left pectoral 
fin are well shown ; and of these the branchiostegal rays 
and infraclavicles are noticed by Traquair, loc. cit. (1875), 
pp. 244, 246. Purchased, 1869, 1888. 

28867. Small head and trunk, much crushed, wanting the caudal 
fin and part of the dorsal and anal fins. 

Purchased, 1854. 

P. 739, P. 1370, P. 1370 a. Two imperfect heads, two portions of 
head and trunk, and an example of the caudal region. 
The first specimen is seen in impression, showing distinct 
traces of the row of minute teeth in the mandible, and 
exhibiting the striated, partly rugose, and tuberculated 
character of the facial bones and the clavicle. The cir- 
cumorbital ring, so far as preserved, shows a radiated 
ornamentation. In the second example of the head, the 
maxilla and the narrow cheek-plate above it are well 
shown. Egerton Coll. 

21547. Trunk having all the fins well preserved. The total length 
of the base of the dorsal fin is about O026, while that of 
the anal is not less than 0*04, and the length of the front 
margin of each is approximately 0-03. The anterior 
border of the pectoral fins also measures O03 in length, 
and that of the pelvic fins about 0*015. The base-line of 
the pelvic fins is much extended, and the caudal fin is 
distinctly inequilobate. 

Presented by Norman McLeod, Esq., 1847. 

21547 a. Larger and more imperfectly preserved caudal region. 

Presented by Norman McLeod, Esq., 1847. 

(iv.) Cromarty. 

19805. Remains of small head and trunk, showing jaws. 

Purchased, 1845. 



PAL^lONJSCTDiE. 455 

(v.) Tynet Burn, Banffshire. 

35777. Much crushed small fish, about 0*175 in length, with well- 
preserved caudal lobe and fin. Purchased, 1860. 

35984. Small contorted fish, with displaced head and opercular 
bones. The left maxilla exhibits the coarse, horizontal 
striation of its expanded portion. Purchased, 1861 . 

36060-61. Another small fish, in counterpart, wanting the caudal 
fin. Purchased, 1861, 

39181. Slightly larger specimen, wanting the caudal fin. The inner 
aspect of the left clavicle and the characters of the pectoral 
fins are well shown ; and immediately behind the upper 
part of the clavicle there are indications of irregularly 
enlarged scales. Boiverbank Coll. 

37384. Much crushed fish, about 0*3 in length, showing part of the 
cranial roof with the pair of longitudinal sensory canals. 
The operculum and suboperculum of one side are displaced 
behind the pectoral arch, the operculum being very narrow 
and deep and marked by oblique, backwardly and down- 
wardly directed striations. Purchased, 1863. 

41310. Fine specimen, distorted on the ventral aspect of the head 
and abdominal region. The cranial roof exhibits the pair 
of longitudinal sensory canals, as noted by Traquair, loc. 
cit. (1875), p. 236 ; and there are remains of the large 
cheek-plate above the maxilla. The operculum is very 
deep and narrow, and apparently ornamented with 
striations or fine rugae obliquely directed backwards and 
downwards ; and the suboperculum seems to be broader 
than deep. Immediately behind the pectoral arch there 
are four enlarged series of scales, gradually decreasing to 
the normal size ; and the change of the squamation upon 
the upper caudal lobe is obvious. The elongation of the 
anal fin described in No. 21547 is again conspicuous • and 
the caudal fin is complete, showing the slight excavation 
of the posterior border and the inequality of the lobes. 

Purchased, 1869. 

P. 342, P. 1370 b. Two specimens, about 0-25 and 0-28 in length, 
the second very imperfectly preserved. Egerton Coll. 

P. 4345. Somewhat distorted small fish, displaying the pectoral, 
anal, and caudal fins, and the double fulcra of the upper 
caudal lobe. Ennislcillen Coll. 



4T)6 ACTINOPTERYGII. 

35778, 35983. Two portions of nodules with crushed remains of 
the head and part of the trunk. Purchased, 1860-61. 

36035. Small trunk with well-preserved fins, wanting the caudal 
pedicle and fin and the greater part of the head. 

Purchased, 1861. 

(vi.) Gamrie, Banffshire. 

The following specimens are preserved in rough, coarse-grained 
nodules, in the same condition as the type of Cheirolepis uragus : — 

19428. Two very imperfect small fishes, the first showing parts of 
the pectoral and anal fins, the second in counterpart, and 
both wanting the dorsal and caudal fins. 

Purchased, 1845. 

28862. Comparatively well-preserved fish, about 0-29 in length. 

Purchased, 1854. 

19805 a. Imperfect remains of head and trunk, ventro-lateral 
aspect, showing branchiostegal rays and the paired fins. 

Purchased, 1845. 

P. 3404. Some scattered bones of the head and scales. 

EnnisTcillen Coll. 
P. 6291. Caudal pedicle and fin. 

The following specimens are more satisfactorily preserved, occur- 
ring in fine-grained compact nodules : — 

47866. Much-crushed specimen, in counterpart, with remains of all 
the fins. Purchased, 1877. 

P. 4049. Imperfect, much-crushed head and trunk, in counterpart, 
displaying the inner aspect of the right clavicle and the 
infraclavicles, and the internal stout rib upon the scales. 

Purchased, 1883. 

P. 4050-52. Three fine specimens, in counterpart, exhibiting most 
of the principal characters of the fish, the second attain- 
ing a length of 0*33. The sculpturing of the scales and 
fin- rays is especially well shown in the first specimen. 

Purchased, 1883. 

P. 5072. Typical specimen, wanting paired fins. 

Presented by John Edward Lee, Esq., 1885. 



PALiEONISCID^E. 



457 



Cheirolepis canadensis, Whiteaves. 

1881. Cheirolepis canadensis, J. F. Whiteaves, Canadian Naturalist, 

n. s., vol. x. p. 33. 
1889. Cheirolepis canadensis, J. F. Whiteaves, Trans. Roy. Soc. Canada, 

vol. vi. sect. iv. p. 90, pi. viii. 

Type. Imperfect fish ; Geological Survey of Canada, Ottawa. 

A larger species than the type, closely similar in proportions, 
but differing in the more advanced position of the pelvic fins and 
the more remote situation of the dorsal. Scales and joints of fin- 
rays pectinated. 

Form. Sf Log. Upper Devonian : Scaumenac Bay, P. Q., Canada. 

Not represented in the Collection. 

Some of the scales described as follows may also pertain to fishes 
allied to the preceding, but they must be regarded as indetermin- 
able : — 

Cheirolepis splendens, E. von Eichwald, Bull. Soc. Imp. Nat. 

Moscou, vol. xvii. (1844), p. 830, and ibid. vol. xix. (1846), 

pt. ii. p. 304, pi. x. figs. 24, 25, and Leth. Rossica, vol. i. 

(1860), p. 1573, pi. lvii. fig. 23.— Devonian ; Marjina, near 

Pawlowsk. 
Cheirolepis unilateralis, E. von Eichwald, torn. cit. (1 844), p. 830, 

and torn. cit. (1846), pt. ii. p. 305, pi. x. figs. 26, 27, and 

torn. cit. (1860), p. 1574, pi. lvii. fig. 14.— Ibid, and River 

Ischora. 
Microlepis exilis, E. von Eichwald, torn. cit. (1844), p. 830, and 

torn. cit. (1846), pt. ii. p. 303, pi. x. figs. 22, 23, and torn. cit. 

(1860), p. 1576, pi. lvii. fig. 12. — Devonian ; River Ischora. 
Microlepis lepida, E. von Eichwald, torn. cit. (1844), p. 830, and 

torn. cit. (1846), pt. ii. p. 302, pi. x. figs. 20, 21, and torn. cit. 

(1860), p. 1576, pi. lvii. fig. 13.— Devonian ; Marjina. 

[The type species.] 

Genus NEMATOPTYCHIUS, Traquair. 

[Ann. Mag. Nat. Hist. [4] vol. xv. 1875, p. 259.] 

Trunk elongated. Mandibular suspensorium very oblique ; den- 
tition in each jaw consisting of an inner sparse row of stout, conical, 
laniary teeth, and an outer close series of small conical teeth ; ex- 
ternal bones striated and tuberculated. Paired fins of moderate 
size, median fins large ; fin-rays stout, distally birfurcating, closely 
articulated, except in the proximal two-thirds of those forming the 



458 vcrrxorTEEYGU. 

anterior part of the pectoral fins ; fulcra minute. Dorsal and anal 
fins not excessively elongated, remote, almost or completely opposed 
to each other. Scales small, very slightly imbricating, and ex- 
ternally striated ; those of the flank deep and narrow, with relatively 
large peg-and-socket articulation. 



Nematoptychius greenocki, Traquair. 

1844. Pygoptei'us greenockii, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. 
p. 78 (undefined). 

1866. Pygopterus greenockii, B. H. Tiaquair, Proc. Roy. Soc. Edinh. 
vol. v. p. 597. 

1867. Pygopterus greenockii, B. H. Traquair, Trans. Boy. Soc. Edinh. 
vol. xxiv. p. 701, pi. xlv. 

1872. Pygopterus elegans, C. W. Peach, Bep. Brit. Assoc. 1871, Trans. 

Sect. p. 109 (name only). [Edinburgh Museum.] 
1875. Nematoptychius greenockii, B. H. Traquair, Ann. Mag. Nat. Hist. 

[4] vol. xv. p. 258, pi. xvi. figs. 7-11 . 
1877. Nematoptychius gracilis, B. H. Traquair, Proc. Boy. Soc. Edinb. 

vol. ix. p. 262. [Collection of Dr. B. H. Traquair.f 
1877. Nematoptychius greenockii, B. H. Traquair, Quart. Journ. Geol. 

Soc. vol. xxxiii. p. 577, and Ganoid Fishes Brit. Carb. Form. (Pal. 

Soc), pi. i. figs. 7-11. 
1879. Nematoptycliius greenockii, B. H. Traquair, Proc. Boy. Phys. 

Soc. Edinh. vol. v. pp. 118, 128. 
1890. Ne?7iatoptychius greenockii, B. H. Traquair, Proc. Boy. Soc. 

Edinb. vol. xvii. pp. 391, 398. 

Type. Imperfect fish ; Edinburgh Museum. 

Maximum depth of trunk contained more than five times in the 
total length ; dorsal contour of abdominal region scarcely arched. 
Head elongated, small, and snout pointed ; head and opercular appa- 
ratus occupying nearly one quarter of the total length ; maxilla orna- 
mented by striae parallel to the hinder and upper margins, passing 
into irregular tuberculations near the alveolar border; dentary 
bone externally tuberculated or irregularly rugose. Pelvic fins 
well developed, arising midway between the pectoral pair and the 
anal. Dorsal and anal fins similar in form, somewhat longer than 
high, the dorsal slightly smaller than the anal and arising immedi- 
ately in front of the latter. Scales externally ornamented with very 
fine, wavy ridges, sometimes branching and anastomosing, directed 
obliquely downwards. 

Form, Sf Log. Calciferous Sandstone Series : Midlothian and Fife- 
shire. Carboniferous Limestone Series : Midlothian and Lanark- 
shire. 



PALiEONISOTD^E. 459 

P. 3445. Head, opercular apparatus, and some anterior scales, pre- 
served in counterpart ; Calciferous Sandstone, Wardie, 
near Edinburgh. The maxilla, dentary, operculum, sub- 
' operculum, branchiostegal rays, and some other bones, arc 
well shown from the inner aspect. Enniskillen Coll. 

P. 846. Similar head, in counterpart, with the imperfectly pre- 
served abdominal region ; Wardie. Portions of the 
external ornament are seen on some of the bones. 

Egerton Coll. 

19815. Fragment of squamation ; Wardie. Purchased, 1845. 

50094. Eemains of jaws : Calciferous Sandstone, Burdiehouse, near 
Edinburgh. Purchased, 1879. 

50088. Fragments of dentary bone ; Calciferous Sandstone, Grange 
Quarry, Burntisland, Fifeshire. Purchased, 1879. 

P. 846 a, P. 3440. Portion of trunk, with dorsal and anal fins, in 
counterpart ; Burntisland. Egerton Sf EnnisJcillen Colls. 

45867. Group of head -bones and scales, associated with similar 
remains of Eurynotus crenatus, noticed by B. H. Traquair, 
Ann. Mag. Nat. Hist. [4] vol. xv. (1875), p. 258 ; Burnt- 
island. Presented by W. Carruthers, Esq., 1874. 

P. 847. -Scattered remains of head and scales, especially displaying 
the mandible ; Carboniferous Limestone (Edge Coal 
Series), neighbourhood of Edinburgh. Egerton Coll. 

P. 4338. Similar group of remains, displaying the maxilla ; Car- 
boniferous Limestone (Edge Coal Series), Wallyford, near 
Edinburgh. Enniskillen Coll. 

Genus CYCLOPTYCHIUS, Young. 
[Bep. Brit. Assoc. 1865 (1866), p. 318.] 

Trunk narrow and elongated. Mandibular suspensorium oblique ; 
teeth in two series, a small outer row and larger, well-spaced lani- 
aries within. Fins of moderate size, with distinct fulcra, and the 
rays distally bifurcating ; principal rays of pectoral fin unarticulated 
except distally ; dorsal and anal fins triangular, short-based, almost or 
completely opposed ; upper caudal lobe slender, and caudal fin deeply 
forked. Scales large, ornamented with ridges chiefly concentric 
with the margins. 



460 ACTINOPTEEYGII. 

Cycloptychius carbonarius, Young. 

1866. Cycloptychius carbonarius, J. Young (ex Huxley, MS.), Rep. 

Brit. Assoc. 1865, p. 319. 
1868. Cycloptychius, Hancock & Atthey, Ann. Mag. Nat. Hist. [4] 

vol. i. p. 362. 

1873. Cycloptychius, T. P. Barkas, Coal Meas. Palseont. p. 36, fig. 140. 

1874. Cycloptychius carbonarius, R. H. Traquair, Geol. Mag. [2] vol. i. 
p. 241, pi. xii. 

1875. Cycloptychius carbonarius, J. Ward, [Proc.J N. Staffs. Nat. Field 
Club, p. 240. 

1875. Cycloptychius, W. J. Barkas, Monthly Rev. Dental Surgery, 

vol. iii. p. 500, figs, lxviii.-lxx. 
1890. Cycloptychius carbonarius, J. Ward, Trans. N. Staffs. Inst. 

Mining Engineers, vol. x. p. 179, pi. iv. figs. 3-5. 

Type. Imperfect fishes ; collection of J. Ward, Esq., Longton. 

The type species, attaining a maximum length of about 0*17. 
Trunk very slightly tapering to the dorsal and anal fins, more 
rapidly contracted beyond; dorsal margin not arched. Head and 
opercular apparatus occupying about one-fifth of the total length ; 
cranial roof-bones rugose and tuberculated, the facial and opercular 
bones with irregular, more or less concentric and parallel striations. 
Dorsal and anal fins equal and opposite, as high as long, arising at 
somewhat less than three-fifths of the total length from the extre- 
mity of the snout ; pelvic fins arising midway between the pectorals 
and the anal. All the scales ornamented with sharp ridges parallel 
with the anterior, inferior, and posterior borders ; principal scales 
of flank not more than one and a half times as deep as broad, the 
postero-inferior angle slightly rounded. 

Form. Sf Log. Coal-Measures: North Staffordshire and North- 
umberland. 

P. 5175-6. Two individuals 0-12 and 0-11 in length, the first being 
in counterpart and wanting the pectoral fins, the second 
showing only a trace of these fins ; Deep-mine Ironstone 
Shale, Longton, N. Staffordshire. Purchased, 1885. 

P. 1011. More imperfectly preserved individual ; Deep-mine Iron- 
stone Shale, Longton. Egerton Coll. 

P. 1011 a. Imperfect trunk displaying the squamation ; Bassey- 
mine Ironstone Shale, Longton. Egerton Coll. 

P. 3447. Well-preserved fish, wanting the pectoral and caudal fins, 
counterpart of specimen figured in the Geol. Mag. [2] 
vol. i. pi. xii. fig. 1 ; Deep-mine Ironstone Shale, Longton. 

Ennishillen Coll 



PALJSONISCID^. 461 

P. 3447 a, b, P. 4333. A much-crushed specimen wanting the end 
of the tail, portions of head and abdominal region, in 
counterpart, and two imperfect examples of the caudal 
region : Deep-mine Ironstone Shale, Longton. 

Enniskillen Coll. 

36899. Imperfect head displaying some of the teeth, and a few 
anterior flank-scales ; Longton. Purchased, 1862. 

39918. Imperfect small individual displaying some of the branchio- 
stegal rays ; Longton. Purchased, 1866. 



Cycloptychius concentricus, Traquair. 

1881. Cycloptychius concentricus, ~R. H. Traquair, Trans. Roy. Soc. 
Edinb. vol. xxx. p. 37, pi. ii. figs. 17-20. 

Type. Pishes ; Geological Survey of Scotland. 

Form and proportions as in the type species ; facial bones and 
opercular apparatus striated, the mandible being slender and taper- 
ing, with a narrow band of tuberculations along its upper margin, 
and the striae below arranged diagonally. Scales ornamented with 
few large rounded ridges parallel with the anterior, inferior, and 
posterior borders ; principal scales of flank slightly more than one 
and a half times as deep as broad, with much rounded postero- 
inferior angle ; scales near dorsal margin almost equilateral, with 
only one or two concentric ridges, the inner area being marked with 
few short diagonal ridges. 

Form. $ Loc. Calciferous Sandstones (Cement-stone Group) : 
Eskdale, Dumfriesshire. 

P. 4063. Somewhat elongated individual, in counterpart, showing 
all the fins. Purchased, 1883. 

P. 4064-66. Three more imperfectly preserved specimens, the first 
in counterpart, and all displaying parts of the squamation. 

Purchased, 1883. 



Genus RHADINICHTHYS, Traquair. 
[Quart. Journ. Geol. Soc. vol. xxxiii. 1877, p. 559.] 

Trunk elegantly fusiform, more or less elongated. Mandibular 
suspensorium very oblique ; teeth in two series, a small outer row 
and larger, incurved, conical laniaries, well spaced, within. Pins 



K)2 ACTIXOIM'ERYGII. 

of moderate size, consisting of delicate rays, distally bifurcated, with 
an anterior series of slender fulcra ; principal rays of pectoral tin 
nnarticulated except near their distal extremity. Dorsal and anal 
tins triangular, partly or completely opposed ; upper caudal lobe 
slender, and caudal fin deeply forked, unsyrnmetrical. Scales 
large or of moderate size, more or less delicately sculptured ; 
ridge-scales iu advance of dorsal fin much enlarged. 



Rhadinichthys ornatissimus (Agassiz). 

18-55. Palceoniscus ornatissimus, L. Agassiz, Poiss. Foss. vol. ii. pt, i. 

p. 92, pi. x. a. figs. (3, 8 (non figs. 5, 7). 
1877. Rhadinichthys ornatissimus, R. H. Traquair, Quart. Journ. 

Geol. Soc. vol. xxxiii. p. 559, and Proc. Roy. Soc. Edinb. vol. ix. 

p. 432. 
1877. Rhadinichthys lepturus, R. H. Traquair, Proc. Roy. Soc. Edinb. 

vol. ix. p. 437. [Imperfect fish ; Edinburgh Museum.] 
1890. Rhadinichthys ornatissh?ius, R. H. Traquair, Proc. Roy. Soc. 

Edinb. vol. xvii. pp. 391, 397. 

Type. Imperfect fish ; Edinburgh Museum. 

The type species, attaining a length of about 0*25. Head with 
opercular apparatus occupying about one-fifth of the total length ; 
greatest depth of trunk immediately behind the operculum, and 
tail-pedicle narrow. Head - bones finely and closely striated. 
Paired fins small, the pectoral about one half as long as the head ; 
dorsal fin arising slightly in front of the anal, shorter than the 
latter, both these fins with much excavated posterior margins. 
Scales of flank relatively large, somewhat deeper than broad . 
Scale-ornament consisting of sharp, delicate striae, mostly paralle 1 
with the superior and inferior margins, sometimes sigmoidally 
curved, with punctures in the intervening furrows ; posterior 
margin serrated. 

Form. 6f Loc. Calciferous Sandstones : Midlothian and Fifeshire. 

P. 3439. An imperfectly preserved fish wanting the head, and an 
imperfect caudal region ; Burdiehouse, near Edinburgh . 

EnnisMllen Coll. 

P. 1000. Remains of small trunk; Gran ton, near Edinburgh. 

Egerton Coll. 

41129. Imperfect small fish ; (?) Burntisland, Fifeshire. 

Br y son Coll. 



I'VL.EOXISCID-E. 



163 



Rhadinichthys carinatus (Agassiz). 

t835. Palaoniscus carinatus, L. Agassiz, Poiss. Foss. vol. ii. pt. i. 

p. 104, pi. iv. c, figs. 1, 2. 
1877. Rhadinichthys geikiei, R. II. Traquair, Proc. Roy. Soc. Edinb . 

vol. ix. p. 438. [Geological Survey of Scotland.] 
1877. Rhadinichthys carinatus, R. H. Traquair, ibid. p. 441, and Quart. 

Journ. Geol. Soc. vol. xxxiii. p. 559. 
1890. Rhadinichthys carinatus, R. H. Traquair, Proc. Roy. Soc. Edinb. 

vol. xvii. pp. 391, 397. 

Type. Imperfect fish ; Edinburgh Museum. 

Trunk slender, the head occupying somewhat more than one- 
fifth of the total length to the bifurcation of the caudal fin. Head- 
bones ornamented with sharp, delicate, wavy striae. Median fins 
relatively large, the dorsal arising slightly in advance of the anal, 
and the latter as long as deep ; fin-rays smooth. Scales of flank 
large, almost equilateral, a few short oblique striae extending from 
some of the denticulations of the hinder border, and others, still 
more delicate, parallel with the inferior border. 

Form. Sf Log. Calciferous Sandstones : Midlothian and Fifeshire. 

P. 844. Fish imperfectly preserved in nodule ; "Wardie, near Edin- 
burgh. Egerton Coll. 

42082. Head and anterior abdominal region : Anstruther, Fifeshire. 

Purchased, 1870. 



Rhadinichthys brevis, Traquair. 

1877. Rhadinichthys brevis, R. H. Traquair, Proc. Roy. Soc. Edinb. 
vol. ix. p. 440. 

Type. Fish ; collection of Dr. R. H. Traquair. 

A species of short and stout proportions, attaining a length of 
about 0*12. Bones of cranial roof ornamented with vermiculating 
flattened rugae, facial and opercular bones with finer striae. Paired 
fins relatively small; median fins well developed, the dorsal and 
anal almost completely opposed. Scales of flank nearly equilateral ; 
posterior border exhibiting five or six prominent oblique denticu- 
lations. Scale-ornament consisting of few, feeble, oblique striae, 
more or less irregularly arranged. 

Form. Sf Log. Calciferous Sandstones : Midlothian. 

P. 845. Specimen wanting the caudal fin ; Wardie, near Edinburgh. 

Egerton Coll. 



4(3-1 ACTIN0PTERYG1I. 

Rhadinichthys elegantulus, Traquair. 

1881. Rhadinichthys geikiei, R. H. Traquair (errore), Trans. Roy. Soc. 

Edinb. vol. xxx. p. 25, pi. i. figs. 13-18. 
1881. Rhadinichthys geikiei, var. elegantulus, R. H. Traquair, ibid. 

p. 27, pi. ii. figs. 1-5. 
1881. Rhadinichthys delicatulus, R. H. Traquair, ibid. p. 29, pi. ii. 

figs. 6-9. [Geological Survey of Scotland.] 
1890. Rhadinichthys elegantulus (with var. delicatulus), R. H. Traquair, 

Proc. Roy. Soc. Edinb. vol. xvii. p* 398. 

Type, Fishes ; Geological Survey of Scotland, Edinburgh. 

A species attaining a length of about 0'1-0*15. Length of head 
with opercular apparatus somewhat exceeding the maximum depth 
of the trunk, and contained slightly more than four times in the 
total length : external bones ornamented with fine, vermiculating 
striae, rarely passing into tubercles. Pectoral fins relatively small, 
their length scarcely equalling more than half that of the head ; 
pelvic fins small and delicate ; dorsal and anal fins of moderate 
size, similar, the former arising very slightly in advance of the 
latter. Elank-scales as broad as deep, ornamented with few very 
delicate, closely arranged striae parallel to the anterior and inferior 
margins, and about four or five large oblique ridges extending 
across the posterior smooth area to a corresponding number of 
large denticulations of the hinder border ; narrow ventral scales 
similarly marked, but with only two or three denticulations ; scales 
of caudal region nearly smooth, with few large denticulations and 
short ridges. 

Form. £f Loc. Calciferous Sandstones (Cement-stone Group) : 
Eskdale, Dumfriesshire. 

P. 4075-6. Pour specimens, one being in counterpart. 

Purchased, 1883. 

P. 4075 a. Imperfect specimen, probably of this species. 

Purchased, 1883. 



Rhadinichthys macconochii, Traquair. 

1881. Rhadinichthys macconochii, R. H. Traquair, Trans. Roy. Soc. 
Edinb. vol. xxx. p. 30, pi. ii. figs. 12-16. 

Type. Imperfect fish ; Geological Survey of Scotland, Edinburgh. 

A small species attaining a length of about 0*025. Length of 
head with opercular apparatus equal to the depth of the trunk 
midway between the pectoral and pelvic fins, occupying nearly one 



PAL^EONISCID.aE. 465 

quarter of the total length. Cranial roof-bones ornamented with 
close, comparatively coarse tuberculations, frequently confluent ; 
other external bones marked with coarse striae, much subdivided 
into tubercles on the mandible. Pins as in R. elegantulus. Scales 
of flank scarcely deeper than broad ; none posteriorly denticulated. 
Scale-ornament consisting of few well-spaced striae parallel with 
the anterior and inferior borders, a few faint oblique ridges also 
crossing the postero-superior area. 

Form. Sf Loc. Calciferous Sandstones (Cement-stone Group) : 
Eskdale. 

P. 4077. Specimen, in counterpart. Purchased, 1888. 



Rhadinichthys cairnsi (Jackson). 

1851. Palceoniscus eairnsii, C. T. Jackson, Rep. Albert Coal Mine, 
p. 23, pi. i. fig. 3. 

1852. Palceoniscus eairnsii, C. T. Jackson, Proc. Boston Soc. Nat. Hist, 
vol. iv. p. 139. 

1877-78. Palceoniscus eairnsii, J. W. Dawson, Canadian Nat., n. s. 
vol. viii. p. 339, and Acadian Geology, Suppl. p. 100. 

Type. Imperfect fish. 

Trunk robust, with slender caudal pedicle, the maximum depth 
somewhat greater than the length of the head with opercular 
apparatus, and contained about four and a half times in the total 
length. Dorsal fin shorter than the anal, arising slightly in 
advance of the latter. Scales of flank scarcely deeper than broad ; 
scale-ornament consisting of delicate transverse striae, partly 
parallel with the inferior border, and terminating in very fine 
serrations of the posterior border. 

Form. § Loc. Lower Carboniferous : Albert Co., New Brunswick. 

P. 2274. Specimen about 0*115 in length • Hillsborough. 

Egerton Coll. 



Rhadinichthys alberti (Jackson). 

1851. Palceoniscus alberti, C. T. Jackson, Rep. Albeit Coal Mine, p. 22, 
pi. i. fig. 1. 

1852. Palceoniscus alberti, C. T. Jackson, Proc. Boston Soc. Nat. Hist, 
vol. iv. p. 138. 

1877. Rhadinichthys albertii, R. H. Traquair, Quart. Journ. Geol. Soc. 

vol. xxxiii. p. 559. 
1877-78. Palceoniscus alberti, J. W. Dawson, Canadian Nat., n. s. 

vol. viii. p. 338, and Acadian Geology, Suppl. p. 100. 
part u. 2i 



466 



.UTIXOPTERYGIl. 



Type. Imperfect fish. 

A small robust species, attaining a length of about 0*08. Maxi- 
mum depth of trunk contained about four times in the total 
length. Head relatively small, and external bones coarsely striated. 
Dorsal fin arising slightly in advance of the anal, and the latter 
much elongated. A continuous series of enlarged ridge-scales from 
the dorsal fin to the occiput ; flank-scales as broad as deep ; scale- 
ornament consisting of irregular transverse striae, more or less 
oblique, terminating in coarse blunt serrations of the hinder border. 

Form. <Sf Loc. Lower Carboniferous : Albert Co., New Brunswick. 

P. 1010. Imperfect specimen, wanting the upper caudal