inhabitmg the United States. 



475 



covered with a smooth and shining, semi-transparent, tes- 

 taceous callus. The margin of the lip is thickened, and 



F 



less widely, and less abruptly reflected, and there is often 

 a prominent tooth-like process on the inner and upper side 

 of the margin near the umbilicus. The color of the epi- 

 dermis is generally much darker. 



In those parts of the eastern and middle States where 

 H. dbolabris abounds, it is in general but about half the 

 size of this species, and is altogether a more delicate and 

 beautiful shell. That this is not the same species, in- 

 creased in size by the influence of a warmer climate, 

 would seem to be proved by the fact that H./allax, Say, 

 is smaller in Florida than in situations much farther north. 

 The color of the respective animals are widely difierent. 



Mr. Conrad informs me that he obtained this shell sev- 

 eral years since, in Alabama, and considered it a new 

 species, but was deterred from publishing it as such, by 

 the generally received opinion that it was only a variety 

 of H. albolabris. 



^' 



2. HELIX ALBOLABRIS 



Plate XIII . 



H. testa orbiculato-convexa, imperforate, luteo-corne^ ; anfractibus 

 transversa striatis; striis crebris, obliquis ; labro albo, expanso, mar- 

 gine late reflexo. 



Synonyms and References. 



Helix albolabris, Say. Nich. Encyc. Am. Ed. Vol IV, 



pi I, Jig. 1. 

 Expedition to St. Peter's River, Vol II, p. 258. 

 American Conchology. No. u, J?/. 13, two upper 



figures. 



-^. 



^■ 



4 



