HIMALAYAN FOSSIL SHELLS. 



109 



it is large and deep, and towards the beak appears some trace of a 

 perforation and its operculum. 



3rdly. Several pieces of a bluish grey limestone, abounding in a 

 plaited variety of Terebratula, and loose specimens of the same. The 

 limestone has imbedded in it some calc spar of a yellowish white colour, 

 and is partly covered with a yellowish earthy powder, of the colour we see 

 in the oolitic countries. The shells themselves differ little from those 

 which are so abundant in the inferior oolite near Bath and elsewhere, and 

 which may be referred to in Mr. Calder's collection — but without Mr. 

 Sowerby's Mineral Conchology to refer to, it is impossible to add the 

 specific name. These blocks also contain No. 1. 



4thly. Many specimens of an equivalve transverse bivalve, trans- 

 versely striated, and the valves crenulated on their interior margin. Its 

 external shape is similar to that of a short variety of Unio, to which it has 

 been referred, but internally it has no lateral teeth, nor any remnant of a 

 lateral ridge ; and though the specimens we have are too much worn to 

 shew what the teeth really were, they appear to have been situated 

 directly vmder the beak. Its flattened and acute beaks, and form ap- 

 proaching to that of a variety of fossil Trigonia of Mr. Calder's, once 

 made me incline to reckon it with that genus. Its shape too a good deal 

 resembles a Venus, but its characters are not satisfactorily made out, 

 and I have not access to any plate or specimen with which I can identify 

 it. With these are some larger specimens of a triangular or rather subor- 

 bicular bivalve, which, in external shape, resembles a Venus or perhaps 

 a Donax, but the characters are not distinct enough for me to venture to 

 give it a name. 



5thly. Several small very transverse equivalved bivalves, about 

 three-fourths of an inch in length, and of a blac k colour ; tiiey appear to 

 be of the genus Modiola. 



