96 



CONCHOLOGY. 



Shell. Orbicular, more or less convex or connoidal above ; the 

 circumference or periphery angulated or keeled ; aperture trans- 

 verse, contiguous to the axis of the shell ; the right margin or lip 

 subangular, often toothed or plaited beneath. Inhabits dry situa- 

 tions in Europe and America. Twenty -two species. 



3. Genus Achatina. PI. X. 



Animal. See Helix. 



Shell. Variable in form, but generally subturriculated, oval or 

 oblong, aperture entire, the right lip sharp, never reflected, colu- 

 mella smooth, of which the anterior extremity is always open and 

 truncated. Inhabits South America. Twenty-two species. 



Achatina perdix. 

 A. immaculata. 

 A. acuta, 

 A. Mauritania. 

 A. ustulata. 

 A. virginea. 

 A, glans. 

 A. Marrainii. 

 A. fusco-lineata. 

 A. columnaria. 

 x\. acicula. 



Achatina zebra. 

 A. purpurea. 

 A. bicarinata. 

 A. castanea. 

 A. vexiilura. 

 A. Priam us. 

 A. Peruviana. 

 A. albo-lineata. 

 A. fulminea. 

 A. foUiculus. 

 A. oleacea. 



4. Genus Anostoma. PI. X. 

 hiimal. See Helix. 



