56 RAMSAY H, TRAQUAIR’S 
more fusiform, less deep and circular than in Wardichthys cyclosoma; the tail 
pedicle is proportionally strong. The scales of the body, where their surface 
is preserved, are ornamented with coarse, irregular, tuberculo-corrugate 
sculpture ; but on the tail pedicle and caudal body-prolongation their markings 
consist of comparatively delicate, wavy, and more or less diagonal furrows and 
ridges. | 
Chetrodopsts, gen. nov. Traquair. 
Body deep, rounded; dorsal fin arising behind the arch of the back. 
Scales very narrow. Cranial osteology and dentition as in Cheirodus 
(Amphicentrum, Young). 
The striking difference in the contour of the body, caused by the absence of 
the dorsal, and probably also of the ventral peak, with the greater shortness of 
the dorsal fin, is sufficient to differentiate this genus from Cheirodus, M‘Coy, 
to which, in cranial structure, it is most intimately allied. (See the author's 
description of Cheirodus in Trans. Roy. Soc. Edin. vol. xxix. 1880, p. 363). 
Cheirodopsis Geikiet, sp. nov. Traquair. 
Pl. V. figs. 17-19. 
Description.—Two specimens of this very interesting form have occurred. 
The first consists of a pretty well preserved head, with the greater part of the 
body and the commencement of the dorsal fin, and when entire probably did not 
exceed 31 inches in length. The second (fig. 17) is considerably disjointed, but 
represents a somewhat larger fish. So far as it is revealed by the more perfect 
of the two examples, the shape of the fish seems to have been deep and 
rounded, with a very large head compared with the size of the body; but the 
absence of the posterior part of the specimen renders it impossible to lay 
down any proportional measurements. 
The contour of the head slopes first gently, then, forming an obtuse rounded 
angle above and in front of the orbit, steeply downwards and forwards 
towards the snout; but the last named part not being preserved, it is impos- 
sible to say whether the premaxilla formed the beak-shaped prominence seen 
in Cheirodus. Where the outer surface of any of the cranial roof bones is 
visible, it is seen to be brilliantly ganoid, and ornamented by tolerably coarse, 
tortuous, and reticulating corrugations. 
Judging from the position vf the opercular bones, the direction of the 
hyomandibular suspensorium was nearly vertical, or with a slight forward 
inclination. The operculum is not so high as the interoperculum, but both are 
higher than broad; in form they resemble pretty closely the corresponding 
plates in Cheirodus. Externally they are ornamented with tolerably coarse 
rugee and tubercles; a diagonal line drawn from the anterior-superior to the 
