226 HELICID.E. 



tiful and regular oblique striae, the last whorl expanding 

 towards the aperture ; aperture transverse, ample, with 

 a testaceous deposit within ; lip thin, acute, not reflected, 

 its lower extremity inserted into the centre of the base ; 

 umbilicus small. 



Greatest diameter more than three-fourths of an inch. 



GEOGRAPHICAL DISTRIBUTION. Inhabits Ohio, Ten- 

 nessee, Mississippi, Georgia, and South Carolina. 



REMARKS. This shell has hitherto been known as a 

 variety of Helix fidiginosa. It seems to me, however, 

 that its characters are so constant that it deserves to be 

 considered distinct from that species, at least provisionally, 

 until the influences controlling the limits of species are 

 better understood. It differs from the preceding in these 

 particulars. The striae of increase are beautifully regular 

 and minute, though prominent, on the upper surface, but 

 hardly noticeable on the lower ; the epidermis is less 

 shining and polished, the spire more prominent, the 

 whorls more convex, and the apex more pointed. The 

 umbilicus is small, and the lip, as it rises from it, a little 

 reflected. The aperture is more transverse, and less cir- 

 cular. There are five full whorls, although it is a much 

 smaller shell. 



The first and only description of this shell, and the 

 only figure hitherto published, are those referred to 

 above. If this and the preceding species are only vari- 

 eties of the same shell, they must both, by the laws of 

 priority, be included under the name of Helix lucubrata. 



