552 



Records of the Indian Museum. 



[Vol. XXIT, 



Localitv. — A single empty but fresh shell was collected by 

 Mr. Sundar Lai Hora in Manipur. 



Affinities. — In spite of its small size this shell does not look 

 like a j'oung specimen of the genus, for the shape is too elongate, 

 the peripheral keel too poorly developed and the aperture too com- 

 plete. There can be little doubt that it belongs to the group to 

 which I have assigned it, but it is unlike any of the Indian or 

 Burmese forms with which I have been able to compare it bj^ 

 means of either specimens or figures. On the whole it seems to be 

 nearer V. ceylonica (Dohrn) than any other, but the shape is much 

 less conical and the base more flattened than in any form of that 

 species. 



Fig. 6.— Opercula of Lecytboconclia and Vivipara. A.- 

 B. — V. o.xvtropis (nat. size). 



-L. lecvtliis (nat. size) 



Lecythoconcha, Annandale. 

 1020. Lecythoconclia, .•\nnandale, Rec. Ind. Miis. XIX. p. 114. 



The shell is of large, sometimes of relatively gigantic size, but 

 thin, smooth or more or less translucent. It is globose inform, 

 with broad swollen whorls, and often bears a striking superficial 

 resemblance to that of Pachylabra (Ampullariidae). The colour is 

 uniform or very nearly so and dark spiral bands are never present. 

 The aperture is large and patent, subcircular or broadly suboval. 

 The columellar fold is not strongly developed, the umbilicus is 

 narrowly perforate and the outer lip is thin. 



The operculum is large, thin but stiff and rather brittle. Ex- 

 ternally it is marked with strong but sharp concentric ridges and 

 bears in its central region a deep funnel-shaped pit. There is no 

 muscular scar on tlie internal surface but the pit is represented by 

 a prominent rounded boss, round which there may be a ring-shaped 

 area on which the surface is slightly roughened. 



