86 



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



DescrijJtion.-- Shell pale olivaceous, turreted, with eight or ten 

 slightly convex whorls, the earlier ones of which are strongly cari_ 

 natcd ; lines of growth curved ; aperture ovate, with a sinus anteriorly. 

 One-inch long. 

 Habitat. — Beaver Creek, N. E. Tennessee. 



Observations. — Bears a general resemblance to M. Virginica. As far 

 as I can judge from the description, it must be 

 somewhat lilio 31. IVarderiana, Lea. — Haldeman. 



Fig. IGO. 



Fis. 1G2. 



The figure is from Prof. Halcleman's type 

 specimen. It is a common species, and in- 

 habits also "West Virginia. 



Tlie following appear to me to be syno- 

 nj^mes : 



M. oblita, — Shell very much carinated, turreted, 

 screw-shaped, rather thin, horn-colored ; spire 

 drawn out; sutures linear ; whorls twelve, acutely carinate ; aperture 

 small, elliptical, within whitish ; columella white and twisted. 

 Habitat. — Tennessee ? 

 Diameter, -30; length, -96 of an inch. 



Observations. — I have about a dozen of this species, which is very 

 distinct from any with which I am acquainted. The locality I am 

 uncertain about, the label being by some accident lost. I 

 believe it comes from Tennessee, but am not certain. Its very 

 marked character of a screw, or rather of a gimlet, strikes one 

 at once. In most species there is a thread-like line above the 

 carina and several below. The carina is not usually per- 

 sistent oa the body-whorl. It is nearest in form and size 

 to M. percarinata, Con., but may be easily distinguished by 

 the absence of granules between the cariuae, the length o 

 the spire, having three or four more whorls, and in being less shiny. 

 The aperture is not quite one-third the length of the shell. — 

 Lea. 



Melania bicostata. — Shell conical, light horn-color, rather 

 thick; spire elevated, acute; whorls 11-12, strongly carinate 

 near the apex and decidedlj' so on each succeeding whorl, not 

 excepting even the body-whorl in most cases, though some- 

 times obsolete there ; carinae often in pairs, near to and 

 parallel with each other; sutures deeply impressed, often 

 with a decided furrow at that point, caused by the carinae. Aperture 



Fig. 163.. 



