﻿;i20 ACTINOPTERYGII. 



Oxygnathus egertoni (Egerton). 



1858. Cosmolepis egertoni, Sir P. Egerton (ex Agassiz, MS.), Figs. & 

 Descrips. Brit. Organic Remains (Mem. Geol. Surv.), dec. ix. no. 1, 

 pl.i. 



1890. Oxygnathus egertoni, A. S. Woodward, Ann. Mag. Nat. Hist. 

 [6] vol. v. p. 432. 



Type. Fish wanting greater portion of head and upper caudal 

 lobe ; British Museum. 



The type species of Cosmolepis, attaining a length of about 0-45. 

 Maximum depth of trunk contained about four times in the total 

 length. Head and opercular apparatus occupying nearly one 

 quarter of the total length; [large teeth apparently more robust 

 than in 0. ornatus] ; cranial roof tuberculated, maxilla and dentary 

 striated. Pelvic fins much smaller than the pectorals, arising mid- 

 way between these fins and the anal ; dorsal and anal fins with 

 numerous short rays, resulting in their slight extension posteriorly, 

 the dorsal somewhat larger than the anal and terminating opposite 

 the origin of the latter. Scales with prominent, sparse, superficial 

 ridges of ganoine. 



Form. &f Log. Lower Lias : Barrow-on-Soar, Leicestershire. 



P. 3508. Type specimen. EnnisTcillen Coll. 



P. 585. More imperfectly preserved fish, exhibiting the upper 

 caudal lobe, described and figured by Egerton, loc. cit. p. 2, 

 fig. 2. Egerton Coll 



P. 5854. Small group of ventral scales. 



Presented by Mrs. Etheridge, 1888. 



The specimens recorded below may pertain to Oxygnathus, but 

 are not generically determinable : — 



P. 959 x. Two maxillae, 0*024 in length, with striated ornament ; 

 Stonesfield Slate. Egerton Coll. 



Genus CENTROLEPIS, Egerton. 



[Figs. & Descrips. Brit. Organic Remains, dec. ix. (Mem. Geol. 

 Surv. 1858), no. 5.] 



Trunk fusiform, robust, and somewhat elongated. Mandibular 

 suspensorium oblique; dentition consisting of an inner series of 

 large conical teeth, well spaced but numerous, and an outer close 

 series of smaller teeth similar in form ; head, opercular and bran- 



