REPORT ON FOSSIL FISHES 35 
the length of the upper lobe, from a point opposite the commencement of the 
rays of the lower one, being 22 inches. These proportions are taken from a 
very perfect and undistorted specimen, whose entire length is 6 inches ; none 
of the others are quite perfect or free from distortion, though the peculiar 
characters of the fish are such as to enable it to be easily recognised even 
from small fragments. 
The head is typically palzeoniscoid in structure, with oblique suspensorium, 
wide gape, ethmoidal prominence, and anteriorly placed orbit. ‘The cranial 
roof bones are ornamented with closely set irregularly contorted ruge, 
frequently interrupted, so as at times to pass into tubercles. The operculum 
is narrow and oblong, the interoperculum, as usual, short and quadrate ; these 
plates are in all cases ill preserved, so that little can be said of their external 
sculpture, save that it seems to be of a striated character. The maxilla is 
of the usual paleeoniscoid shape, and has its broad postorbital portion covered 
with wavy and contorted ridges, which in most instances pass into a narrow 
band of irregularly shaped tubercles stretching along the dentary margin. 
The mandible is very stout, its depth posteriorly equalling # of its length, in 
shape it rapidly tapers towards the symphysis. Externally it is covered with 
closely set, slightly wavy ridges, which, running from behind forwards, diverge 
from each other along a longitudinal line placed rather below the middle of the 
bone, on whose upper and lower margins they obliquely impinge, but the 
strie forming the lower side of this somewhat feather-like pattern are much 
more horizontal in direction than those on the upper. The jaws are armed 
with conical teeth of two sizes, large ones being placed at short intervals 
inside a row of minute external teeth. 
The bones of the shoulder girdle are striated with tolerably coarse wavy 
ridges, which on the upper or vertical part of the clavicle are again fretted with 
minute transverse indentations. 
The scales of the body are of moderate size, rhomboidal, and tolerably thick. 
On the front part of the flank (figs. 2,3) they are tolerably equilateral, with slightly 
concave upper and convex lower margin ; the covered area is very narrow, the 
articular spine moderate in size, and the keel of the attached surface only 
slightly developed. Towards the tail (fig. 5) and along the back the scales 
become smaller and more oblique, and in front of the dorsal fin there are four 
or five imbricating median scales of a larger size. Along the belly (fig. 4) they 
become very low and narrow, and on the caudal body-prolongation, as usual, 
small and acutely lozenge-shaped, while imbricating V-scales clothe the upper 
margin of this part. The scales are marked externally by a very ornate and 
easily recognised sculpture, though it is excessively difficult by means of words 
to give anything like an adequate description of its peculiarities. It consists 
of sharp furrows or grooves, sometimes interrupted and intercalated, some of 
