432 Mr. A. S. Woodward on some Ganoid Fishes 



bones and branchiostegal rajs delicately striated, and the 

 opercular bones almost smooth. Fins of moderate size or 

 small, the rays broad, distally bifurcating, and more or less 

 covered with a very thin layer of ganoine ; the rays of the 

 pectoral fins, except the few short ones placed hinder most, 

 articulated only at the distal extremities, all others uniformly 

 articulated to the base ; fulcra minute or absent. Dorsal and 

 anal fins triangular in shape, somewhat longer than high, 

 and the hinder rays very short ; dorsal opposed to the space 

 between the pelvic and anal fins ; upper caudal lobe narrow 

 and much attenuated, with small ridge-scales, the fin deeply 

 forked and symmetrical. Scales thick, small, or of moderate 

 size, very narrow ventrally, and ornamented with delicate, 

 oblique lines of ganoine, in part bifurcating and branching, 

 becoming very faint upon the anterior dorso-lateral region 

 and partly subdivided into tubercles. 



The only character of generic value in Oxygnathus ornatus 

 that still remains doubtful is the relative length of the anal 

 fin, no known specimen exhibiting this appendage so satis- 

 factorily as desirable. That it will prove to be elongated, 

 however, seems evident from the fact that in every other 

 generic character the so-called Cosmolepis Egertoni is identi- 

 cal with Oxygnathus, and the elongation of the anal fin is 

 distinct in the type specimen of that fish. Moreover, the so- 

 called Thrissonotus Colei is not separated from Oxygnathus 

 ornatus even by specific characters, and in this case the anal 

 fin is again distinctly elongated. This fish owes the pecu- 

 liarities of its squamation entirely to the fact that it occurs in 

 a very hard nodule, which has split in such a manner as to 

 destroy the superficial scale-ornament, and exhibit the struc- 

 tural lines of growth. All the ordinary specimens of Oxy- 

 gnathus ornatus occur in the well-known soft Lias clay, and 

 thus exhibit the superficial ornamentation more or less 

 intact. 



To the synonymy of Oxygnathus ornatus the present 

 writer would thus relegate the so-called Thrissonotus Colei, 

 the species being as yet known only from the Lower Lias of 

 Lyme Regis ; and the more deeply fusiform species, hitherto 

 named " Cosmolepis" may be termed Oxygnathus Egertoni, 

 this being at present peculiar to the Lower Lias of Barrow- 

 on-Soar. 



Genus Coccolepis. 



Three imperfectly preserved specimens in the British 

 Museum indicate the occurrence of a new small Palseoniscid 



