tW^^HIt'^ 



inhctbiting the United States 



481 



Greatest transverse diameter three fourths of an Inch. 



Geographical Distribution. ^^ An exceedingly nu- 

 merous species in the moist forests on the margin of the 

 Mississippi, near the Ohio," according to Mr. Say. It 

 is also common in the States bordering upon the Ohio 

 river, but has not been noticed east of the Alleghany 

 mountains. 



Remarks. This is a beautiful soecies, distil 



fruis 



by its shining epidermis, its crowded and delicate raised 

 striae, and the numerous reddish-brown revolving lines 

 which contrast well with the russet or yellowish ground 

 on which they are traced* The lines vary in number 

 from three or four to thirty or more, and are sometimes 

 united into bands. On the sides and base of the shell 

 they are usually finely undulated. The general contour 

 of the shell resembles H, thyroidus^ Say. I have never 

 been able to obtain the living animal, and have therefore 



Mr 



Ac- 



V 



cording to Dr. Ward " they inhabit wet and marshy 

 prairies under sods. Two winters since I found in such 

 a situation (in December) at least one hundred of this 

 species ao^orlutinated into one mass. They were about 

 six inches below the surface and appeared to have exca- 

 vated the cavity which they occupied." This habit of 

 attaching themselves together in great numbers during 

 their hybernation I have not witnessed in any other of 

 our species, but I believe it is common in some of the 

 European species. 



VOL. I. PAJRT ir 



62 



