ACHATINID^. 59 



Corona^ Albers, 1850. Shell usually sinistral, oval-oblong; 

 spire elongated, subturreted, summit obtuse ; whorls eight, the 

 last two-thirds the total length ; aperture semioval ; columella 

 tortuous, plicate, callous above, slim at the base, truncate ; 

 peristome simple, sharp ; outer lip uniting with the columella 

 at a sharp angle. 0. regina^ Fer. 



Orthalicinus, Crosse and Fischer, 18*75. 0. fa^;ciaia, Miill. 

 (xcmi, 39). Cuba, Flotida. 



Calycia, Adams, 1865. 0. crydallina, Reeve. Waigiou, 

 Malay Archipelago. 



LiGuus, Montfo'rt, 1810. (Chersina, Beck [pt.], 18.3T. Pseudo- 

 trochus, M'irch, 1852.) Shell imperforate, solid, elongately 

 conical, apex acuminate, variously fasciate with gaj'' colors ; 

 whorls 7-8, the last about one-third the total length ; columella 

 straight, in the adult distinctly truncate ; aperture lunatel}' oval, 

 subangulate ; peristome simple, acute, the margins joined by an 

 entering callus. 0. virginea^ Linn, (xcviii, 40'. 6 sp. West 

 Indies. 



Porphyrobaphe, Shuttl., 1856. Shell imperforate, oblpng, 

 solid, usually plicately striate, apex obtuse; whorls 6-8, the last 

 ventricose ; columella thick, plicately twisted ; aperture oblong- 

 oval ; peristome thickened, expanded-reflected, margins united 

 by a thin callus. 0. iostoma, Sowb. 12 sp. So. America. 



Family ACHATINID^. 



Shell moderately thick, with more or less elongated spire ; the 

 last whorl generally ventricose ; aperture large ; columella trun- 

 cate at the base ; peristome usually simple, sharp. 



Jaw finely plicate or costulate, thin ; central tooth very small, 

 laterals tricuspid, with the central cusp much the longest, mar- 

 ginals short, tricuspid. 



AcHATiNA, Lam., 1199. 



Etym. — Agate-shell. 



Syn. — Cochlitoma, Fer., 1819. Oncaea, Gistel, 1848. 



Distr. — 73 sp. Mostly African ; arboreal. A. zehra^ Chemn. 

 (xcviii, 43). 



Shell oblong-oval, with conical spire, very rarely turricu- 

 lated, sometimes sinistral ; whorls 6-9, the last more or less 

 ventricose ; columella tortuous, arcuated, truncate below ; aper- 

 ture oval, expanded below, sharply angulated behind ; peristome 

 sharp ; lips united by a more or less callous shining deposit. 



The Achatini are the largest of all land-shells, even exceeding 

 the great Bulimi of the Borus group which replace them in the 

 similar latitudes of South America ; like them, the eggs are 

 large, with a calcareous shell, being over an inch in length. 



Homorus, Albers, 1850. Imperforate, turreted, apex obtuse. 



