Prof. E. Forbes on Fossil Invertebrata from Southern India. 157 



On all the specimens there are fifteen plications on the outer side, seven on the 

 expansion, and six on the inner unexpanded portion of the shell. The canal of 

 the back is very regular. The near allies of this species are Ostrea carinata, 0. 

 pectinata and 0. larva, all cretaceous. 



Locality, Pondicherry. 



3. Ostrea amorpha, G. B. Sowerby, MSS. PI. XV. fig. 24. 



O. testel irregular!, crass^, subaequivalvij valvA superior! obtuse plicate. 

 Length 2 inches. Breadth 1 inch. 



Whilst there can be no question that this formless oyster is distinct from any 

 other species in the collection, it is impossible to describe it in more definite terms 

 than those given in the diagnosis. 



Locality, Trinchinopoly. 



4. In the Verdachellum collection are bad specimens of a fourth species of 

 Oyster, very nearly allied to, if not identical with, the greensand Ostrea prionota ; 

 but better examples are required for certain determination. 



Articulata. 



Crustacea. 



The carapace of a Crab is contained in the Pondicherry collection, and is repre- 

 sented in Plate XVI. fig. 12. 



Annelida. 

 Genus Ditrupa, Berkeley. 



1. Ditrupa? longissima, sp. nov. PI. XIX. fig. 13. 



D. testa cylindrica, longissima, arcuata^ concentrice regulariter striata,, striis minutissimis 

 (nucleo laevi). 



Length of specimen 4^ inches. Diameter O^q inch. 



A very long, regularly curved, cylindrical shell. The surface is marked with 

 very minute concentric striae. The cast is smooth. The habit is so truly that of 

 a testaceous tubicular Annelide, and the regularity of form so similar to the aspect 

 of a Ditrupa, that, although the mouth is not preserved, I have little hesitation in 

 referring it to that well-marked genus. 



It is contained in a mass of rock from Pondicherry, and is associated with Ba- 

 culites and various univalve and bivalve shells. 



VOL. VII. SECOND SERIES. 



