CYCLOSTOMA. 349 



at rest and retired witliin its shell, from adhering by 

 means of its foot, as is usual with the Hehcidoe, the ani- 

 mal has the power of spinning a short thread, which is 

 attached to the ohject of support ; and by this it hangs 

 suspended at pleasure. 



Shell conic cylindrical, or turreted, truncate at tip, 

 the surface finely cancellate -with raised, longitudinal, 

 and revolving threads. Color varying from yellowish 

 to brown, usually with darker brown bands, which are 

 generally interrupted in such a manner that the colors 

 also form longitudinal stripes. Whorls, when complete, 

 seven ; but the three uppermost are usually lost ; they 

 are rounded, and separated by a deep, crenulated suture. 

 Aperture rounded ovate, a little angular posteriorly ; lip 

 a little reflexed, white. Base with a minute perforation. 



Length half an inch ; diameter one-sixth of an inch. 



Geographical Distribution. It is abundant at 

 Key AVest, both in woods and open places. 



Remarks. This is the only representative of the 

 genus within the United States, and appears to be iden- 

 tical with a species from Cuba, from which island it was 

 probably derived. Mr. Say's description, however, pre- 

 ceded that of all others. It is of the pupoid form, like 

 that characteristic of the West India species generally, 

 and would come under the true genus Cyclostoma, even 

 as restricted by Dr. Pfeiffer. There is some latitude in 

 the size of the shell, and also in its more or less conical 



