[152] 



Animal large, narrow ; head extensile ; tentacles narrow, with 

 eyes on tubercles at their external bases. 



Remarks. — This family is also, like the last, of West Indian 

 extraction, where it flourishes greatly, the species being numer- 

 ous, well marked, in most cases very beautiful, and varying 

 greatly in size and ornamentation. 



Genus HELICINA, Lamarck. 



1. Helicina orbiculata, Say. 



Plate 18, figures 17—19, 26. 



Subglobose, not angulated ; spire conical, apex. acute; solid; 

 whorls 5, with well impressed suture ; aperture large, semilunar, 

 lip reflected, and greatly thickened in old individuals. White 

 (bleached), yellow, brown or gray, with frequently a pale or 

 colored band on the periphery, and large or small, more or less 

 numerous lines or spots. 



Height 6, diam. 9 mill. 



Tennessee, Mississippi, Georgia, Alabama, Florida, Texas. 



A large, white variety, with greatly thickened lip, known as 

 jr. tropica, Jan., occurs plentifully in Texas. (Fig. ::6.) 



2. Helicina occulta, Say. 



Plate 18, figures 20, 21. 



Small, subglobose, depressed-conical, striated, solid ; whorls 

 5, nearly plane, angular at periphery ; aperture small, half round, 

 lip thick. "Xellowisb or brownish. 



Height 5, diam. 6-5 mill. 



Found fossil and bleached in the post-tertiary of the Western 

 States, Indiana, Ohio, Mississippi, etc. Mr. W. G. Binney 

 mentions having received an apparently recent specimen from 

 Shelboygan, Wis. Mr. Jacob Green, who described this same 

 species subsequently to Mr. Say, gives as a locality " Hills, 

 Western Pennsylvania." His specimens were undoubtedly re- 

 cent. To this I have to add that at Lexington, Virginia, the 

 species now exists numerously. 



