38 



five, carlnate, or with an acute shoulder, which is almost concealed 

 on the spire by the suture ; it becomes more obtuse and almost 

 obsolete, or even impressed on the body whorl, but near the 

 labrum it is again very obvious ; the whole surface has slightly 

 elevated, somewhat regular lines, forming grooves between them 

 across the whorls, and there is an appearance of revolving lines 

 on the body whorl, particularly beneath ; labrum entire, thick, a 

 little reflected, obtusely a little more prominent towards the base, 

 but not angulated. 



All the specimens I have found are dead and bleached. They 

 occur abundantly in the ragged and abrupt " bluff,'' half a mile 

 below JNew Harmony, near the river bank, with many Helices that 

 are commonly found in the Western States. They are much of 

 the same size or even a little larger than the Helicina orbiculata, 

 Ao6., which species is destitute of carina or of prominent wrinkles 

 or elevated lines, its labrum is reflected, but not thickened, with 

 a distinct angle near its base. 



Sl'CCINEA vermeta. — Shell suboval, yellowish, very thin and 

 fragile, somewhat diaphanous, with nearly three very oblique 

 volutions ; whorls very much rounded, wrinkled ; suture very 

 profoundly impressed ; spire rather prominent and acute ; aperture 

 ovate, the superior termination rounded. 



Inhabits margins of ponds near New Harmony. 



This species is remarkable for the very deep indentation of its 

 suture, giving to the whorls of the spire the appearance of being 

 almost separated from resting on each other ; and by this char- 

 acter it may be readily distinguished from the other species of this 

 country. It was found by Dr. Troost. 



S. UNDULATA. — Shell suboval, pale yellowish, translucent, 

 fragile; volutions three and a half; spire moderate, wrinkles 

 obsolete, body whorl wrinkled, or rather slightly undulated: 

 columella narrowed, so as to exhibit the appearance of an interior 

 umbilicus, when viewed with a lens from the base. 



Length about one-half inch. Inhabits Mexic >. 



Very similar to S. ovalis, Nob., but the suture is not so deeply 

 indented, and it has from one-half to three-fourths of a whorl 

 more ; the surface of the body whorl also is rather undulated than 

 wrinkled. One of the individuals lived nearly twelve months in 

 my cabinet, without any apparent sustenance. 



