of Edinburgh, Session 1876 - 77 . 
429 
opposite the interval between that fin and the ventrals, although the 
latter are not shown in the figure. The anal is, however, well 
shown in one specimen ; it is large, triangular, and acuminate, and 
is closely followed by the caudal, which is very powerful. The fin 
rays are externally ganoid and finely striated ; their transverse 
articulations are very close ; the fulcra are closely set, and minute 
for the size of the fish. The scales of the body are proportionally 
small. Those of the front part of the body are apparently nearly 
equilateral, but posteriorly, and more especially towards the ventral 
margin, their form is low and narrow. Their anterior covered area 
is very narrow ; the posterior margin is very finely denticulated. 
The exposed area is covered with a delicate yet sharply-defined 
ornamentation, consisting of fine sub-parallel ridges which pass from 
before backwards across the scale in a gently sigmoid direction, 
tending to become intermixed with punctures posteriorly, especially 
above the diagonal between the two acute angles of the scale. 
Towards the tail the ridges become less marked on the posterior part 
of the scale, giving way to the thickly dotted punctures, till, on the 
caudal body-prolongation, the former, after lingering at the anterior 
margin, altogether disappear, and punctures alone remain. 
Very little can be made out concerning the bones of the head ; 
however, in the above mentioned entire specimen the lower jaw is 
seen to be very stout, and ornamented externally with fine, sharp, 
closely set, wavy, branching, and anastomosing and interrupted 
ridges running in a longitudinal direction. The laniary teeth are 
very strong, incurved, and smooth, with apical enamel cap ; similar 
teeth are seen on the maxilla, the dental margin of which is finely 
tuberculated. 
Remarks. — The structure of the pectoral fin, the relative position 
of the dorsal and anal fins, and the form of the latter, show clearly 
that this species is not a “ Pygopterus,” to which genus it was 
referred by Agassiz. On the other hand, its affinities to Elonichthys 
striolatus are unmistakable, though it attains a larger size. In this 
and in some other respects it resembles considerably the three large 
species from the Coal-measures of North Staffordshire, which I have 
recently described as Elonichthys semistriatus , caudalis , and oblongus * 
*Memoirs of -the Palaeontographical Society for 1877, “Carboniferous 
Ganoids,” pp. 49-57. 
3 L 
VOL. IX. 
