318 HELICID^. 



and fusiform. The ■whorls are nearly flat, the surface 

 shining, and marked with numerous angular striae, 

 which, on the hack of the last whorl, attain sometimes 

 the prominence of wrinkles. The lip is often very thick ; 

 it is not added until the shell has acquired at least 

 seven or eight full volutions. The outline of the external 

 aperture is an oval, whose greatest diameter is parallel 

 with the axis of the shell, truncated obliquely by the 

 columellar margin ; internally, it is modified by a lamel- 

 lar tooth or fold on its superior parietes, and another 

 marking the depression of the axis ; when these are pro- 

 minent the outline of the throat of the aperture is some- 

 what trilobate. One or both of the teeth are sometimes 

 wanting. The apex of the spire is corneous. Its color 

 is chalky or hoary white, with frequently a livid broivn 

 tint beneath. 



This species is nearly allied to Pupa uva and P. 

 mumia of M. Lamarck, and, together with those and 

 perhaps some other species, constitutes a sub-generic 

 group peculiar to the West India Islands and the main 

 land in their vicinity. This group has not been suffi- 

 ciently studied, and needs elucidation. In the opinion 

 of some, it consists of a single species with numerous, 

 strongly marked, local varieties. 



[ This shell was described by Dr. Binney as a new 

 species, and is refei'red to in the first volume under the 

 name, P. incana ; and the plate representing it is so 

 lettered ; but it is so evidently the P. maritima of Dr. 

 Pfelffer that it would be deviating from scientific rules to 



