158 AURICULACEA. 



Shell imperforate, elliptically ovate, rather thin, shining 

 when perfect, but usually found much eroded ; the surface 

 is marked with longitudinal wrinkles, and very minute 

 revolving striae ; horn-color, or grayish-red, often with re- 

 volving, narrow, rufous bands, four or five in number; 

 suture well marked ; spire short, and usually obtuse, often 

 somewhat eroded ; whorls usually 6, the upper ones flat- 

 tened, the body whorl equalling about I of the entire length 

 of the shell, and obtusely angulated at its greatest width ; 

 aperture hardly oblique, very long and narrow, enlarging 

 gradually towards the base, about f the length of the shell | 

 peristome very thin and sharp, not reflected, on the interior 

 furnished with no laminae, or with from one to seven; 

 these laminae are elongated, white, and do not reach the 

 margin ; they are usually separate, placed at irregular in- 

 tervals, but sometimes are found on a longitudinal ele- 

 vated, white callus; they enter but a short distance into 

 the aperture ; the parietal wall of the aperture is covered 

 with a thin, shining, enamel-like callus, and bears on its 

 lower half a single, white, prominent and transverse tooth, 

 entering into the aperture ; the columellar is also furnished 

 with a white, tooth-like fold, commencing at the termina- 

 tion of the sharp peristome, and revolving upwards into 

 the interior of the shell ; this fold does not extend far into 

 the aperture, as all the internal whorls and axis of the shell 

 are early absorped by the animal. 



Length of an unusually large individual 13, breadth 7 

 millimetres. 



Geographical Distribution. I have this species from the 

 vicinity of Boston, from New Jersey, and South Carolina. 

 Say found it at the mouth of the St. John's River, in 

 Florida, and in Maryland ; Mittre gives Virginia ; Pfeiffer, 

 Georgia ; DeKay, New York. Stimpson did not detect it 

 farther North than Massachusetts Bay. It may, therefore, 

 be said to range from that point southward along the 



