LITHASIA. 37 



Habitat. — Coosa River, Alabama : E. R. Showalter, M.D. 



Diameter, -34 ; length, -CO of au inch. 



Observations. — I have nine specimens before me of this little species, 

 which has much the aspect of an Anailosa, as well also of some 

 Melanioi. But the callus on the lower and upper parts of the colu- 

 mella naturally places it in Lithasia, The longest of these specimens 

 is not moi'e than half an inch, and all are banded precisely alike, the 

 three bauds being nearly of equal size and equidistant. It would 

 appear then that these bauds are more constant than usual in the 

 Melanidce. Four out of the nine have a light purple spot on the 

 middle of the columella, the others are entirely white. Without 

 being at all like Melania obovata, Say (consanguinea, Anth.), in out- 

 line or general appearance, the columella is very much the same, both 

 being thick with an incipient channel at base. Indeed, M. obovata 

 properly belongs to the genus Lithasia. In form, color and bands, 

 nuclea reminds one of 31. basalts (nobis), but it is more rotund, has a 

 thicker columella, has a less brilliant epidermis and is a more solid 

 shell. The aperture is about one-half the length of the shell. Dr. 

 Showalter says in his letter that " this is the most uniform species in 

 my collection." — Lea. 



D. jShell subcylindrical. 

 11. Ii. brevis, Lea. 



Melania brevis, Lea, Philos. Proc, ii, p. 242. Philos. Trans., ix, p. 6. Obs., iv, p. 



26. WiiEATLEY, Cat. Shells U. S., p. 24. BiXNEV, Check List, No. 38. Bkot, 



List, p. 32. Keeve, Monog., sp. 344. 

 Anculosa solkla, Lea, Philos. Proc, ii, p. 243. Philos. Trans., ix, p. 29. Obs., iv, 



p. 29. WnE.\TLEY, Cat. Shells U. S., p. 28. 

 Leptoxis solida. Lea, Binney, Check List, Ko. 384. Brot, List, p. 25. 

 Melania trivittata, Reeve, Monog., sp. 420. 



Description. — Shell striate, subcyliudrical, somewhat solid, yellow; 



spire rather short: sutures impressed; whorls flattened; 



Fig. S3, 

 columella thickened above ; aperture ovate, white. 



Habitat. — Alabama. 



Diameter, -41 ; length, -CO of an inch. 



Observations. — A single specimen only of this species 

 is before me. The apex being eroded, the number of 

 whorls cannot with certainty be ascertained; there ap- 

 pear to be about five. On this specimen there are eight indistinct 

 impressed striae, and several low, irregular folds on the body- 



