286 NEW MELANIDiE OF THE UNITED STATES. 



smaller and thicker species, and has a distinct carina. It is also less attenuate. The 

 specimen from Clinch River is pale horn-color. Those from Tellico Creek are nearly 

 all furnished with 2 to 4 bands. Two of the three from French Broad are of a deep 

 purple. The aperture is about one-third the length of the shell. 



I have great pleasure in naming this after my deceased friend, Joseph Clark, to 

 whom I am indebted for many species brought by Prof. Christy. 



Teypanostoma incubvum. Pi. 36, fig. 109. 



Testa carinata, conoidea, subtenui, cornea ; spira subelevata ; suturis regulariter impressis ; anfractibus 



octonis, plarmlatis, infeme obsolete striatis ; apertura parviuscula, rhomboidea, intus albida ; labro 



aeuto, sigmoideo ; columella valde contorta. 



Shell carinate, conical, rather thin, horn-color; spire somewhat elevated; sutures 



regularly impressed ; whorls eight, flattened, obscurely striate below ; aperture rather 



small, rhombical, whitish within ; outer lip acute, extremely sinuous ; columella very 



much twisted. 



Proc. Acad. Nat. Sci., 1862, p. 171. 



Hab. — Florence, Alabama, Rev. G. White. 



My cabinet and cabinet of Mr. White. 

 Diam. -37, Length -89 inch. 



Remarlis. — Among the Melanidoe sent to me by Mr. White, I found three speci- 

 mens of this species which being near to Thorntonii, herein described, evidently was 

 supposed to be the same species. It is however, a smaller, more slender and thinner 

 species, and the remarkable sinuous edge of the outer lip at once marks the difference. 

 The inward curve, starting at once in that direction from the suture, turns forward 

 before it reaches the periphery of the whorl and again curves to the base, making a 

 complete sigmoid curve. The aperture is about one-third the length of the shell. 



Teypanostoma Postellii. PI. 36, fig. 110. 



Testa carinata, pyrarnidata, subcrassa, cornea ; spira regulariter conica; suturis valde impressis; anfrac- 

 tibus octonis, vel planulatis vel impressis, ultimo parviusculo ; apertura parvissima, rhomboidea, intiis 

 albida ; labro acuto, vald6 sinuoso ; columella inferne incrassata et valde contorta. 



Shell carinate, pyramidal, rather thick, horn-color ; spire regularly conical ; whorls 

 eight, flattened, the last rather small ; aperture very small, rhomboidal, whitish with- 

 in ; outer lip acute, very sinuous ; columella thickened below and very much twisted. 

 Proc. Acad. Nat. Sci. 1862, p. 171. 



Hab. — Tennessee River, J. Postell ; North Alabama, Prof. Tuomey. 



My cabinet and cabinets of Mr. Postell and Dr. Hartman. 

 Diam. -35, Length -85 inch. 



BemarJes. — I have from Mr. Postell eight specimens, and from Professor Tuomey five. 

 They vary very little, but most of them are imperfect at the apex or outer lip. This 

 species very closely resembles Thorntonii, herein described, but is a much smaller 

 species, with a smaller aperture and compressed whorls. All the specimens before 



