136 Records of the Indian Mm^cvin. [Vol. XIV, 



body-whorl, which is obliquely transverse and usually shorter than 

 the spire. Except the smaller whorls of the protoconch none of the 

 whorls are swollen or shouldered. The suture is not impressed except 

 above the fifth and seventh whorls and there only slightly. The 

 aperture is broadly ovoid, oblique, of moderate size, hardly angulate 

 posteriorly, broadly rounded anteriorly. The columella is strongly 

 arched, the coluraellar callus broad, smooth, and polished. The outer 

 lip is thin. 



The spiral sculpture commences on the third complete whorl, on 

 the dorsal surface of which a faint groove appears. As this groove 

 curves round the shell its margin becomes gradually raised until it 

 assumes the appearance of a pair of smooth highly convex ridges. The 

 double ridge thus formed proceeds on to the fourth whorl, becoming 

 gradually stronger and assuming a granular structure. On the sixth 

 whorl it becomes regularly tubercular and a single ridge appears below 

 it at the base of the whorl near the inner edge of the dorsal surface. 

 Almost from its point of origin this new ridge has a squamous appear- 

 ance, and bears small, not at all granular projections. On the body- 

 whorl the primitive paired ridge persists, but its tubercles become 

 irregular and more or less confluent. The ridge that appeared on the 

 sixth whorl also persists and grows stronger, its projections taking 

 the form of short spiniform processes, blunt at the tip and concave 

 outwards and forwards. Below this ridge there are two and a half or 

 three others, all of which are rather feebly developed and undulate 

 rather than tubercular. 



Measurements of shells {in millimetres). 

 Total length 



Greatest breadth (without projections) 

 Length of spire (on dorsal surface) 

 Length of aperture 

 Breadth of aperture 



The colour of the external surface of the shell is very pale olivace- 

 ous green tinged with ferruginous brown. The protoconch is brownish 

 or colourless ; the fifth and sixth whorls are paler than the body-whorl 

 but the colour is shaded gradually. The spiral ridges are a little darker 

 than the rest of the surface, but there are no definite dark spiral bands. 

 The shell substance is whitish and translucent, except in the proto- 

 conch, in which it is bluish-grey. The inner surface is whitish, tinged 

 with brown, but with opaque white bands corresponding in position 

 with the spiral ridges. This surface is lustrous and has a milky opalesc- 

 ence. The columellar callus is brown externally and white inter- 

 nally, very highly polished. 



The embryonic shell, removed from the parent at full time, con- 

 sists of six whorls, but the apical whorl, which often disappears in the 

 adult shell, is minute. The external colour is very pale green with 

 several light brown spiral bands. The shape is sub-conical, but the 

 main axis is oblique and the part surrounding the aperture somewhat 

 produced. The first five whorls have a different character from the 

 sixth, in which there is an abrupt change of direction in the spiral. 

 The minute apical whorl is smooth ; on the second whorl a rather 



