e Pupa found in the United States. 401 
two smallest teeth are wanting. Indeed I have found 
only one specimen in which the little basal tooth is 
present ; while there is very frequently an additional 
tooth on the outer lip, posterior to the others. If we 
except P. placida, a somewhat doubtful species, it is 
the largest Pupa of the' United States, and.is not 
likely to be confounded with any other. 
PUPA PRÓCERA. 
Plate IIL fig. 12. 
P. testa cylindraceà, elongata, apice obtus&; anfractibus sex, con- 
vexis, obliqué striatis ; apertura semi-ovali, dentibus sex armata, quo- 
rum posterior emarginatus. 
Shell elongated, ovate-cylindrical, obtuse at apex, 
of a brownish horn-color; whorls six, convex, the 
three anterior ones of nearly equal diameter, and the 
three posterior ones forming a very obtuse apex ; 
suture deep; aperture semi-oval, rather longer than 
broad ; lip brown, somewhat incumbent at the middle 
of the right side, unequally reflected, not flattened; 
and curving at an abrupt angle before it joins the 
preceding whorl; throat armed with five teeth ; one 
on the middle of the transverse lip is compressed, 
stretehing towards the junction of the outer lip, and 
emarginate at the middle, sometimes even bicuspid ; a 
conical one on the pillar a little below its junction 
with the transverse lip, and sometimes there is a 
small denticle at the base of this ; a smaller one at 
the'anterior termination of the pillar; a small one, 
often wanting or inconspicuous without a large mag- 
nifier, about the middle of the outer lip; and the 
VOL. III. — NO. II, 51 
