198 



POPULAR CONCHOLOGY. 



Acme. Hartmann. (Acicula Hartm. ; Pupula Agass.) 

 Shell sub-cylindrical, with a blunt apex ; mouth ovate, 

 simple, thin, slightly reflected over the pillar, form- 

 ing a slight perforation.* Animal, very like that of 

 Cyclostoma, but having rather slender and long ten- 

 tacula ; the eyes placed at their hinder bases ; foot 

 sharp behind. 



The type is A.fusca, found in Europe; A. Uneata is 

 a minute British species, living amidst fallen leaves. 



Geomelania. Pfief. — Shell turret-shaped, not um- 

 bilicated; aperture entire, curved outwardly; the edge 

 simple, reflected, and the base having an appendage. 

 Animal, not satisfactorily described; an operculum. — 19 

 species. 



These shells are found in Jamaica. 



Truncatella. Risso. (Choristoma De Cr. et Jan.) 

 — Shell cylindrical, turreted, and either broken _ 

 off at the apex, or obtusely truncated ; the ^ | 

 whorls are smooth, transversely ribbed ; aper- 

 ture oval, and the lips united ; operculum oval, 

 and somewhat spiral. Animal with short diverg- 

 ing triangular tentacula, the eyes placed cen- T j}™%p£ a 

 trally at their inner bases ; head bilobed, more 

 or less muzzle-shaped ; foot short, rounded at both ends.f 

 — 15 species; also fossil. 



Mr. Reeve | remarks that the animal is probably am- 

 phibious, from the following experiment by Mr. Lowe : — 

 " A specimen was taken out of the water by this gentle- 

 man on the coast of Madeira, together with several other 

 aquatic Molluscs, and they were all put away together in 



* Sowerby's Conchological Manual. 



t Forbes's British Moll. j Conch. Syst. 



