10 THE NAUTILUS. 



on top. When four pairs of teeth are present they are equally 

 spaced at intervals of 90 and this appears to be the normal 

 arrangement as only a few shells show three pairs which are 

 spaced from 100 to 120. The single fully adult shell (figured) 

 appears to have but 2 pairs of teeth, but the shell is a dead one 

 and quite opaque. Two young shells, 1.5 mm diameter with 

 3.5 whorls and 2.5 mm. diameter, with 4.5 whorls, each have 

 3 pairs of teeth. 



Greater diameter 5, lesser 4.5, altitude 2 mm. 



Collected by Herbert H. Smith in a "Cove" on the Cumber- 

 land Plateau, 3 miles north of Anderson, Franklin Co. , Tenn. 



Types No. 9159 of my collection. Paratypes in the collections 

 of the Academy of Nat. Sci., Philadelphia, and Bryant Walker, 

 Detroit, Mich. 



This species belongs to the same group as V. capsella lacteodens 

 and V. andrewsx. It differs from both by the smaller size and 

 wider umbilicus and from andrewscs by the tubercular teeth 

 arranged in pairs. 



I name this species after Dr. H. A. Pilsbry whose "Revision 

 of Paravitrea", Proc. Acad. Nat. Sci., 1903, pp. 204-212, Pis. 

 X, XI, has done much to clear up this most interesting group. 



A NEW FOBM OF AMPULLABIA 



BY WILLIAM HEALEY DALL. 



AMPULLARIA (FELIPPONEA) NERITINIFORMIS n. sp. 



Shell solid, whitish or lurid purple under an olivaceous rather 

 strong periostracum, frequently banded with four or five purple- 

 black broad spiral bands which are most conspicuous on the 

 white inside of the outer lip, the white interspaces being subequal ; 

 these bands however show but little on the exterior except at 

 resting stages, in the specimens examined; the form of the shell 

 viewed from behind, strongly recalls that of Neriiina reclivata or 

 meleagris though with a rounded base; from in front it looks like 

 a short spired heavy Campeloma. The nucleus is small and 



