96 Sir P. Egerton on Fossil Fishes from Southern India. 



in size and form with the Indian species, although the latter has a very distinctive 

 feature in the cessation of the cutting edges before they reach the base, giving a 

 constricted appearance to the shaft of the tooth. This character is well-marked 

 in Odontaspis contortidens of the Molasse ; indeed our Pondicherry fossils are only 

 distinguishable from this species by the absence of the striae on the inner surface 

 of the teeth. 



Odontaspis oxyprion, Eg. — The last species I propose to describe in this memoir 

 is also frequent in the Indian collections. It belongs without doubt to the 

 genus Odontaspis, and is very nearly aUied to 0. rhaphiodon. The compa- 

 rison, however, is less accurate than I could wish, owing to my not being 

 able to refer to Agassiz's plate on the subject ; but one character establishes at 

 once the distinctness of the Indian species, viz. the absence of striae on the inner 

 surface of the tooth. Some of the specimens of this species are in a good state of 

 preservation, showing the form of the base and the lateral cusps. It is not impos- 

 sible that more than one species may be included in this description, as some of 

 the specimens are more convex than others on the outer surface, and less recurved 

 at the point. The number and form of the lateral cusps also vary considerably ; 

 but there is a general resemblance which induces me for the present to include all 

 under one denomination. In the form of the central cone they agree very closely 

 with Odontaspis rhaphiodon ; but the lateral cusps are larger, more elongated, and 

 sharper at the points, and in these respects they exceed even the recent Odontaspis 

 ferox. They are sometimes single, sometimes double, on each side, and occasion- 

 ally single on one side and double on the other. The base is broader and less 

 deeply notched than in 0. rhaphiodon. 



A considerable number of specimens remain to be examined ; but most of them 

 will probably belong to one or other of the species described above. Should any 

 distinct forms be found, they will be treated of in a future memoir. 



