104 HELICID^. 



Mississippi River, 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 species, distinguished 

 by its shining epidermis, its crowded and delicate raised 

 striae, and the numerous reddish-brown revolving lines, 

 which contrast well mth 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 they are 

 usually finely undulated. The general contour of the 

 shell resembles that of Helix thyroidus. It is in general 

 thinner and more fragile than other shells found in the 

 same region, and varies very much in size ; individuals 

 with the mature lip occur, not exceeding half an inch in 

 diameter. It is occasionally entirely destitute of lines 

 and bands, and in one or two instances I have noticed 

 the epidermis of the living shell to be white. 



It would appear from the statement made by Dr. Kirt- 

 land that their habits are somewhat peculiar. " Wet 

 marshes are its principal resort, -where, during summer, 

 it may be seen chmbing about on weeds and blades of 

 grass, apparently endeavoring to avoid the water col- 

 lected beneath it. At the approach of Avinter it retreats 

 to the tops of the carex-bogs, where several dozen may 

 be found collected together in a torpid state, with the 

 mouths of their shells closed with an epiphragm. They 

 usually form a shallow excavation on the bog, concealed 



