100 LAND AND FRESH-WATER SHELLS OF N. A. [PART IV. 



•without them. The aperture is rather more thau one-third the length 



of the shell. — Lea. 



41. P. carinatum, Lea. 



Tnjpanostomn carinatum, Lea, Proc. Acad. Nat. Sci., p. 4, 18C4. Jour. Acad. Nat. 

 Sci., vl, p. U8, t. 23, f. 62, 1807. 



Shell carinate, acutel}' conical, reddish horn-color, thin, transparent ; 



spire acutely conical and sharp at the point; sutures very much 



impressed ; whorls about nine, carinate and striate above ; 

 Fig.191. t' ' 



4 aperture rather small and rhomboidal ; outer lip acute, sinuous ; 

 columella somewhat thickened and twisted. 

 Habitat. — Bull Run, tributary to Clinch River, East Tenn. 

 Diameter, -19; length, -44 inch. 

 Observations. — Two specimens only were received, having some- 

 what the aspect of young shells, but I suspect they are nearly if not 

 quite mature. It is evidently a delicate species. It has rather a wide 

 channel, with the outer lip not much produced. In outliue it resem- 

 bles Melania (Goiiiobasis) sculptilis (nobis), but differs from it geuer- 

 ically as well as in being shorter in the spire and in not having deep 

 striae over the whole of the whorls. The aperture is more than 



one-third the length of the shell. — Lea. 



That this species is very young is evident, and I have a 

 conviction that it will be found to be the quite j'oung of 

 P. aratum. 



42. P. lativittatum. Lea. 



Trypanostoma lativittatum, Lea, Proc. Acad. Nat. Sci., p. 273, 1832. Jour. Acad. 

 Nat. Sci., V, pt. 3, p. 352, t. 39, f. 223. Obs., ix, p. 174. 



Description. — Shell carinate, subattenuate, rather thin, shining, 



dark, broadly banded; spire conical; sutures linear; whorls 



Fiff.192. 

 about seven, flattened above, yellow at the base ; aperture 



small, subrhomboidal, broadly banded within ; outer lip sharp, 



sinuous ; columella bent in, thickened below. 



Habitat. — Chikasaha River, Alabama; "NY. Spillman, M. D. 



Diameter, -20; length, -02 inch. 



Observations. — This is a small, gracefully formed species, with a 

 very broad, intensely brown band around the middle of the whorl. 

 There is a second narrow band immediately under the suture. The 



