228 ME. ATTHEY OX PAL^EOXISCUS HAXCOCEX 



in the fresh state be filled with connective cartilage and liga- 

 ment, just as the corresponding space is in the recent Ceratodus 

 Forsteri. 



The articular bone of Ctenodus is of about the same length as 

 the inner plate or ramus which bears the teeth, slightly convex 

 on the outer surface, and marked by five or six apertures for 

 vessels ; it is pointed upwards in front like the prow of a boat. 

 Its posterior border presents two scallops, the upper somewhat 

 larger than the lower, which extends to the posteriorly project- 

 ing point of the lower border, which is convex ; the upper scal- 

 lop ends at a rounded projection, which separates it from the 

 upper border. This border presents two shallow concavities, 

 the anterior occupying the greater part of the border ; the pos- 

 terior has a projection on its inner side, somewhat in the form 

 of a bracket, for the support of the teeth of the inner plate or 

 ramus. 



On a thin slab of shale from Newsham in my possession, and 

 which measures five by three and a half inches, are seen imbed- 

 ded one rib, several bones of the head, fragments of scales, and 

 what I take to be right and left vomerine teeth of Ctenodus, one of 

 which is figured on Plate Y., fig. 4. The teeth are four-tenths 

 of an inch broad, and thick at the base, their outer surfaces 

 being slightly convex, and their inner slightly concave, the two 

 surfaces converging from the base to the thin, convex, serrated 

 or toothed margin, which is two-tenths of an inch long. The 

 microscopic structure of these teeth corresponds exactly with 

 that of the maxillary teeth of Ctenodus. 



I possess about a dozen other specimens believed to be vomer- 

 ine teeth of Ctenodus, in close proximity on the same slabs to the 

 bones of the head and teeth of Ctenodus; some of these are a 

 little larger, others a little smaller, than the two above described. 



Pal^onisctts Hancocki, n. sp. 



This elegant little fossil fish I have ventured to name after 

 my late, lamented friend, Mr. Albany Hancock. 



It measures from two inches and a half to three inches aud 



