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° to120°. 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. andrewse. It differs from both by the smaller size and 
wider umbilicus and from andrewse 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, Pls. 
X, XI, has done much to clear up this most interesting group. 
A NEW FORM OF AMPULLARIA. 
BY WILLIAM HEALEY DALL. 
AMPULLARIA (FELIPPONEA) NERITINIFORMIS 0D. 8p. 
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 Neritina reclivata or 
meleagris though with a rounded base; from in front it looks like 
a short spired heavy Campeloma. The nucleus is small and 
