27 



others at Harrigate. The smallest teeth of the labium are some- 

 tiuies obsolete. 



V. PENTODOX. — Shell dextral, subovate, "whitish horn color ; 

 apex obtuse, whorls five, glabrous, convex ; suture not very deeply 

 impressed ; aperture semioval ; labium two-toothed, of which a 

 single very prominent one is on the middle of the transverse por- 

 tion or true labium, and the other is remote, much smaller, and 

 placed in the basal angle of the columella: labrum regularly 

 arquated, tridentate, tooth nearest the base very small, and placed 

 near the smaller tooth of the columella, the two others larger, 

 subequal ; umbilicus distinct. 



Length less than one-tenth of an inch. 



Animal — tentacula two, rather long and thick, cylindrical 

 obconic, retractile, with a rounded oculiferous extremity ; two 

 hardly elevated truncated tubercles instead of the anterior tenta- 

 cula : foot white ; head and neck, as far as the mantle, black. 



Inhabits Pennsylvania. The lower tooth of the labrum is some- 

 times obsolete. 



Melampus obliquus. — Obconic, reddish brown, rather thick ; 

 spire very little elevated ; whorls eight or nine, wrinkled across ; 

 labium Avith two very distinct teeth, and an intermediate and 

 equidistant slight obtuse prominence ; inferior tooth very oblique, 

 terminating at the base ; labrum with about eight teeth or striae, 

 which terminate on the margin ; base of the aperture a little 

 contracted by the basal tooth. 



Length more than seven-twentieths of an inch. I am indebted 

 to Mr. Stephen Elliott for this species, who obtained it on the 

 coast of South Carolina. It is closely allied to Bulimus monile, 

 Brug., but it has no appearance of bands, which distinguish that 

 shell. In the collection of the Academy are specimens from the 

 West Indies. 



In the Journal of the Academy, vol. v., page 119, et seqq., anno, 1825. 



Helix pallax. — Spire convex ; volutions five, with elevated 

 lines forming grooves between them ; labrum reflected, contracting 

 the aperture, bidentate ; teeth separated by a profound sinus ; 

 superior tooth inflected into the mouth ; inferior tooth situated 

 near the base ; labrum with a large, prominent, oblique, lamelliform 



