210 



Records of the Indian Museum. 



[Vol. XVI 



Bithynia costigera is a small shell differing considerably from 

 the common, widely spread, smooth form in having ribbing on 

 the whorls: vide figure in Conchologia Indica, plate 151, fig. 10. 

 The generic distinction is indicated even on shell character and is 

 also to be expected in the animal, which should be examined. It 

 does not occur in Bengal as stated by Preston. At least I have 

 never met with specimens from the Gangetic delta. It is a common 

 shell in Peninsular India, recorded by Nevill in his Hand-List 

 from Karnul, Conjeveram and S. India (30) ex. W. T. B^anford 

 and Madras Museum collections ; also from Ceylon (30) ex. E. L. 

 and F. I^ayard coll., together with a subvar. ctirta^ 6. Nevill, ob- 

 tained by him at Bangalore. 



The Blanford collection presented to the British Museum 

 contains specimens from South India named B. sulcata, Evd. and 

 vSoul. 



As it was so important that the animal of Bithynia costigera 

 should be examined I asked my friend Dr. N. Annandale if he could 





CA/. 



/, 



biG. \a. — Fossariiiiis stacliei, Neumayer. 



(Enlarged from Neumayer's original figure). 



'"iG. ib. — Mysoria costigera (Kiister) var. cKrta (Nevill). 



(Enlarged photograph ( x 4) of shell from type locality). 



help me. This he has not only been able to do, but he has most 

 kindly had photographs and drawings made of the shell, radula, 

 and operculum, together with an enlarged photo of Neumayer's 

 original figure of Fossarulus stachei , which now illustrates this 

 paper, — for which I thank him much.' 



I cannot do better than give in full the result of his examina- 

 tion of specimens he had collected at Bangalore, the original 

 localit^^ of var. curia, Nevill ; for they add much to the value of 

 this communication, and confirm my idea we are dealing with a 

 new genus of freshwater shells very distinct from Bithynia. For 

 this the name Mysoria seems applicable, if it has not been used 



' Since this was wrillen I have obtained fresh specimens of M. costigera in 

 the neighbourhood of Madras. The animal, so far as appears on a superficial 

 examination, does not differ from that of Bithynia except in having shorter ten- 

 tacles. As, however, I am just starting on a long journey I have not been able 

 to make a detailed examination. I hope that Col. Godwin-Austen will do this 

 later and publish the results. N. Annandale, 8-X-1918. 



