130 RAPANINiE. 



Genus SEPARATISTA, Gray. 



Shell turbinate, subdiscoidal, the first whorls contiguous, 

 the last more or less separated; aperture expanded, slightly 

 angulated, the margin everted; umbilicus very wide, in- 

 fundibuliform, with the whorls visible as far as the apex. 



Syn. ? Lippistes, Montf. 



Ex. S. Chemnitzii, A. Adams, pi. 14, fig. 6. 



This curious genus seems somewhat to approach Ra- 

 pana in conformation and texture. One species is from 

 the Philippines, another is from Japan, and Say has 

 described one as a species of Delphinvla. 



Species of Separatista. 



Blainvilleana, Petit. Grayi, A. Adams. 



Chemnitzii, A. Adams. laxa, Say. 



Genus MELAPIUM, H. and A. Adams. 



Shell ovato-pyriform, ventricose, imperforate, porcella- 

 nous ; spire obsolete, apex papillary ; aperture expanded ; 

 inner lip with a thick, smooth callus at the hind part ; 

 columella twisted anteriorly, with a prominent obhque 

 plait; canal wide, recurved, directed towards the left. 



Syn. Pyrula sp.. Lam. 



Ex. M. lineatum, Lamarck, pi. 14, fig. 7. 



The porcellanous texture of the shell of Melapium ap- 

 proximates it to Pusionella, from which, however, it is dis- 

 tinguished by its ventricose body-whorl and short papillary 

 spire ; from Rapana the absence of umbilicus separates 

 it. The animal and operculum are at present unknown. 



