130 GENUS XXIX. HELIX. 



hollowed laterally by the convex projection of Ihe last 

 whorl but one (see Helix Conm arietis, pL 8. /. 105). 



Helix. Shell globular or orbicular, with a convex or conic 

 spire ; aperture entire, Avider than long, hollowed at the 

 vipper part by the convex projection of the last tiu'n but 

 one (see Helix Pomatia, pi. 8. /. 11 0). 



SiGARET. Shell depressed, somewhat ear-shaped ; spire short, 



and little elevated ; the aperture entire, spread out very 



wide, longer than wide (see HeUx haliotoidea, pi. 8. 



/.111). 



The last Lamarck places with the Naked MoUusca, the shell 



being inclosed in the skin, like Bulla aperta. 



Perhaps here we may place Lamai'ck's genera of Helicina 



and Testacella, as follow : 



Helicina. Shell somewhat globular, no umbilicus; the aper- 

 ture entire, semi-oval ; the pillar thickened, compressed 

 at the base (see List. Conch, t. 61. f. 59). 



Testacella. Shell univalve, obliquely conic, the summit a 

 little spiral ; aperture oval, the left lip rolled inwards (see 

 Favanne, 76). 



