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



only visible with a lens. I have seen no such marks on any other 

 species. In outline it is closely allied to striatiila (nobis), but it is a 

 smaller species, and has not the cancellation of that species. The ap- 

 erture is rather more than one-third the length of the shell. The 

 outer lip is broken. — Lea. 



The specimen figured by Mr. Lea being imperfect, I give a 

 figure from a shell" in Coll. Smithsonian Institute. This spe- 

 cies is evidently described from an immature specimen. 



198. G. crenatella, Lea. 



Melania crenatella, Lea, Proc. Acad. Nat. Sci., v, pt. 3, p. 268, t. 35, f, 79, March, 

 18o3. Obs., ix, p. 90. Binney, Check List, No. 76. Brot, List, p. 34. Reeve, 

 Monog. Melania, sp. 457. 



Description. — Shell transversely striate, high turreted, subcostate, 

 somewhat folded, rather thin, dark brown, almost black; spire ele- 

 vated, closely folded at the apex; sutures very much impressed; 

 whorls seven, flattened, covered with transverse ribs ; aperture small, 

 oval, banded within ; columella whitish, incurved ; outer lip some- 

 what contracted and very crenulate. 



Habitat. — Coosa River, Uniontown, Alabama; E. K. Showalter, M.D. 



Diameter, -IG ; length, -50 of an inch. 



Observations. — Five specimens of this very beautiful little species 

 are before me, all of which I owe to the kindness of Dr. Showalter. 

 Fig. 575. Most of these have eleven closely-set, thread-like, transverse 



tribs on the last whorl, which are very dark brown, while the 

 interspace is yellowish. On the next whorl above there are 

 usually six, and above these the number diminishes to three. 

 There appear to be about seven whorls. Within the aperture of four 

 out of the five specimens there are brown bands accompanying 

 the lines of the outer ribs, and these terminate in little furrows 

 at the edge, which cause the outer lip to be beautifully and regularly . 

 crenulate. One of the specimens has the ribs without color, and 

 therefore it is without bands inside. It is allied to Melania (^Gonio- 

 basis) striatula (nobis), but is a much smaller species, moi'e cylin- 

 drical, of a darker color, and has stronger rib-like stria;. — Lea. 



