1921.] B. Prashad : Notes on Lamcllibranchs. 149 



Distribution. — Prime's specimens were obtained in the Nico- 

 bars, while all those in the Indian IMuseum are from the Anda- 

 mans. Some of these, as already noted, had provisionally been 

 identified as B. violacea, Brug., but they do not belong to that 

 species. 



Batissa inflata, Prime. 



1915. Batissa inflata, Preston, Faun. Brit. hid. Fyeihvi. Moll., p. 208. 



For previous references to this species Preston's volume, 

 cited above, may be consulted. 



In the Indian Museum there is a specimen from the Anda- 

 man Islands which I assign to this species. It differs from the 

 shells of B. similis in the shell being more oblique and, as the 

 name indicates, inflated, the umbones more anteriorly placed and 

 greatly recurved forwards, the anterior margin shorter and more 

 slanting, the posterior margin more curved and not biangulate, 

 the podium more marked and the ventral border less arched. 

 The hinge is much more arched but all the teeth are comparative- 

 ly smaller, broader and coarser, the laterals are more serrate and 

 the cardinals sharper. 



The single specimen from the Andaman Islands measures 76 

 mm. X 68 mm. X 45 mm. ; it is smaller than Prime's type-speci- 

 men which was collected in the Nicobar group. 



