121 
color. This species like the canrena, seems subject to many 
varieties. On two apecimens, for which I am indebted to Mr. 
Stone, the pale yellowish-brown color is covered by a cinereous 
tinge, and on one of them two lower series of spots towards the 
labrum are confluent at their inner extremities into one series ; in 
another specimen the spots of each series are so confluent with 
each other on the back of the shell and towards the^ labrum as to 
represent three continuous bands. 
I have not yet found this species so far South as G-reat Egg 
Harbor. 
From the examination of some specimens of Naticse, from the 
same coast, presented by Mr. Collins, I am inclined to think that 
this species grows to a considerable size, and attains the length of 
two and three-fifths inches, that it then loses its spotted bands, but 
always retains the whiteness about the umbilicus, and this latter 
part as well as the callus, and indeed the whole outline of the shell, 
remains unaltered. 
Yolvaria canaliculata. — Shell whitish, immaculate, cylin- 
dric, with very minute obsolete wrinkles ; spire convex, very little 
elevated, mammillated at tip ; volutions about five, with their 
shoulder very obtusely grooved ; labrum with the edge arcuated 3 
labium overspread with a calcareous lamina, and with a single 
oblique fold or small tooth near the base. 
Length from three-twentieths to nearly one-fifth of an inch. 
I received specimens of this singular shell from Mr. Elliott, of 
South Carolina, who obtained it on the coast of that State. The 
arcuated form of the edge of the labrum is only perceived when 
the part is viewed in profile. 
Nassa unicincta. — Shell yellowish-white or cinereous, subo- 
vate-conical 3 whorls with numerous revolving lines and transverse 
undulations, the former about eleven or twelve in number, with 
often a smaller obsolete one in the intervening spaces 3 undula- 
tions about ten to the body whorl, placed at the distance of the 
length of their own diameter apart, and somewhat closer on the 
spire 3 whorls eight 3 apex acute 3 body whorl with a brown band, 
sometimes obsolete, interrupted by the undulations, and consisting 
of about two spots in each of the intervening spaces 3 labrum 
within with ten parallel striae, which revolve on the inner surface 
11 
A 
