13 
{h) Imperfect licacl and abdominal squamation, in connterpaid. 
(e) I'hc scattered remains of a tisli, among wliicli maii}^ scales are well 
shown (PL IV, Pigs. 2-7). 
{(1) Imperfect caudal ingion, partly shown of the natural size in PI. Ill, 
Pig. 6. 
Sp. Char . — The type species, attaining a length of ahout 0‘1T. Length 
of trunk from the pectoral areli to the l)ase of the caudal hn equalling 
scarcely more than threc-([uartcrs of the maximum depth ; the dorsal margin 
gil3hously curved, the A-entral margin mor(‘ regularly arched. Head Avith 
opercular apparatus occupying slightly more than one-quarter of the total 
length of the fish to the base of the caudal tin. Pelvic tins arising much 
nearer to the anal than to the ])ectorals ; the dorsal tin, with ahout tAventy- 
f our rays, arising considerably in advance of the middle point of the hack and 
extending nearly to the base of the caudal tin; the anal tin, Avith seventeen 
rays, opposed to the hinder tAvo-thirds of the dorsal, and tlie length of its 
foremost ray equalling nearly lialf of the maximum deptli of the trunk. The 
thickened abdominal squamation terminating ahrujitly at a liiu' joining the 
origin of the dorsal and anal tins. 
Head and Opercular Apparatus. — Tlic cranium is short and triangular, 
deeper than broad (PI. IV, Pig. 1), and the frontal profile is angulated, there 
being a rounded bend in the roof immediately in advance of and above the 
orbital space. None of the elements of the cranial roof can be distinguished ; 
but there seems to lie a large, paired, square element behind, Avhich is 
CAudently supra-temporal. The narrow forward extension of the parasphenoid 
bone is consjiicuous below the orbit ; and immediately beneath this is a large 
smooth jilate, longer than deep, representing a Avell-developed bony pterygo- 
quadratc arch. The form and projiortions of the jaAA'S are indistinguishable ; 
and unless some obscure indications in the type specimen are produced by a 
cluster of minute, short styliform teeth, there is no evidence of the dentition. 
TTic opercular apjiaratus is narroAV : and unless appearances are deceptive in 
No. h, the operculnm is especially deep in proportion to its Avidth. So far as 
shoAvn, all the head and opercular bones are externally tuberculated. 
Axial Skeleton of Trunk. — The axial skeleton of the trunk is exposed 
only in the hinder portion of the fish, Avhere the thinness of the squamation 
permits of its being distinctly observed. The notochord must have been 
persistent, and the short, expanded neural and hmmal arches in the caudal 
