North American Land Snails 



among the tree branches which are their homes ! They harmonise 

 with the brilliant tropical vegetation. Diameter, i inch. 

 Habitat. — Cuba. 



Genus SAGDA, Beck 



The Tied Helix (//. alUgans, Ads.), is thimble-shaped, 

 with a concave, depressed base and blunt apex. Whorls eight 

 to ten, flattened, the last one faintly keeled. The lines of growth 

 show as faint, diagonal striae. The white shells are invested 

 with a yellowish horny epidermis. The aperture is semi-lunar; 

 lip thin, sharp. Umbilicus wanting. Height and width, i inch. 



Habitat. — Jamaica. 



Genus POLYGYRELLA, Binney 



Shell a flat spiral, with wide umbilicus ; coils seven to eight, 

 cross-ribbed above; glassy, shining, yellowish, horn-colour; 

 lip not expanded, thickened at edge by white rim, and armed 

 with two or three teeth; columella bears triangular tooth. 



The single species, P. polygyrella, Bland and Cooper, J inch 

 in diameter, lives in the spruce forests of the Coeur d'Al^ne 

 Mountains in Idaho. 



Genus PLEURODONTE, Fisch. (CAROCOLUS, Montf.) 



Shell large, solid, more or less flattened; whorls four to six, 

 rounded or keeled; lip flaring or reflexed, generally toothed. 

 Eggs large, oval, hard-shelled; foot undivided, sides granular; 

 mantle edge frilled. 



A tropical American genus of large ground snails whose 

 nearest relatives inhabit China, the East Indies and Australia. 

 The genus exhibits a great variety of forms. 



The Wavy Pleurodonte {P. sinuata, Miill.) has its door- 

 way narrow and guarded by white teeth or wide and smooth- 

 rimmed. The variation in form is from a top-shaped cone to a 

 lens with keeled rim. There is also a wide-mouthed nerite form. 

 Brown banded with yellow, white, wound with yellow, and 

 unhanded shells, from chocolate to cream, indicate the range 



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