77 
Nassa vibex. — Shell cancellated ventricosed cinereous or pale 
reddish-brownd with two or three irregulard sometimes obsolete 
darker fascia ; body whirl with twelve thickd prominent costad and 
about as many revolving filiform lineSd which are not much ele- 
vatedd and but simply crenate the costa and lip labrum incrassatedd 
with about two more prominent teeth within ; labium callous ; spire 
shortd rapidly attenuated to an acute tip. 
Length three-fifths of an inch. Inhabits the southern and mid- 
dle coast. Cabinet of the Academy and Philadelphia Museum. 
Rather rare. I found but four specimens. For the locality of 
the coast of the Middle StateSd I am indebted to my brothei’d Mr. 
B. Sayd who brought me a specimen from the shores of Mew Jersey. 
Nassa trivittata. — Shell conic acutCd yellowish-whitCd can* 
cellate so as to appear granulatedd granules prominentd equidistant ; 
ten revolving impressed lines on the body whirld and a somewhat 
more conspicuous groove near the summit of each volution ; spire 
as long or longer than the bodyd and with a rufous revolving line 
near the suture ; body whirl trilineate with rufouSd the lines placed 
one near the suturCd one on the middled and the third rather 
darkerd at the origin of the beak ; suture regular and deeply im- 
pressed ; beak distinguished by a profound depressiond from the 
body whirld slightly reflected ; labrum not incrassated, with raised 
lines within upon the fauces which do not extend quite to the 
edge of the lip ; labium distinctly lamellard with an obsolete fold 
of the basal edged and a tooth near the superior junction with the 
labrum. 
Length about seven-tenths of an inch. Inhabits the Middle and 
Southern States. Cabinet of the Academy and Philadelphia Mu- 
seum. A very common species. 
It somewhat resembles Maton and Rackett’s figure of Biiccinum 
maculay (Linn. Trans. Lond. vol. 8d) in the cancellated appearancCd 
but it is a longer shell and destitute of the incrassated aperture. 
This species is closely allied to the genus Plios of Montfortd by the 
striated labruiUd and the projection or slight fold at the base of the 
columellad whichd in the system of that authord is an essential one. 
Nassa obsoleta. — Shell ovate-coniCd subacuted cancellated ex- 
hibiting a granulated appearancCd dark reddish-browUd or blackish, 
sometimes tinged with olivaceous ; spire shorter than the body • 
suture not deeply impressed ; beak not distinguished from the body 
