HELIX. 1<J7 



slender, eyes black ; foot narrow, thin, semi-transparent, 

 receiving its color, in some degree, from the substance 

 on which it is placed, not projecting behind the she'll 

 when in motion ; length less than twice the breadth of 

 the shell, which it carries nearly horizontally. 



SHELL discoidal, sub-carinated ; epidermis corneous ; 

 whorls from less than six to more than eight, narrow, 

 compressed, diminishing very gradually in width from 

 the aperture to the apex, with raised, acute, transverse 

 lines, which are nearly obsolete on the base ; lip com- 

 monly white, continuous round the aperture ; outer lip 

 reflected, with a groove behind the reflection, regularly 

 rounded so as to describe two-thirds of a circle ; pillar- 

 lip with an acute fold, or tooth, projecting towards the 

 aperture ; base showing from two to four volutions in the 

 same plane, with a moderate umbilicus, extending to the 

 apex. 



Greatest transverse diameter nearly five-eighths of an 

 inch, commonly much less. 



GEOGRAPHICAL DISTRIBUTION. Inhabits Georgia, 

 Florida, Alabama, and Texas. Very common on the 

 Sea Islands. I noticed immense numbers of them on a 

 small island in St. Joseph's Bay, Florida, under the 

 decaying leaves of the palmetto, in company with Ht'li- 

 cina orbiculata. 



REMARKS. The compressed, discoidal shape of this 

 shell, and its numerous narrow whorls revolving around 



