77 



Nassa vibex. — Shell canccllate, ventricose, cinereous or pale 

 reddish-brown, with two or three irregular, sometimes obsolete 

 darker fascia ; body whirl with twelve thick, prominent costa, and 

 about as many revolving filiform lines, which are not much ele- 

 vated, and but simply crenate the costa and lip ; labrum incrassated, 

 with about two more prominent teeth within ; labium callous ; spire 

 short, 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 States, I am indebted to my brother, Mr. 

 B. Say, who brought me a specimen from the shores of New Jersey. 



Nassa trivittata. — Shell conic acute, yellowish-white, can- 

 cellate so as to appear granulated, granules prominent, equidistant j 

 ten revolving impressed lines on the body whirl, and a somewhat 

 more conspicuous groove near the summit of each volution ; spire 

 as long or longer than the body, and with a rufous revolving line 

 near the suture ; body whirl trilineate with rufous, the lines placed 

 one near the suture, one on the middle, and the third rather 

 darker, at the origin of the beak ; suture regular and deeply im- 

 pressed ; beak distinguished by a profound depression, from the 

 body whirl, 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 lamellar, with an obsolete fold 

 of the basal edge, 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 Bmcinum 

 macula, (Linn. Trans. Loud. vol. 8,) in the cancellated appearance, 

 but it is a longer shell and destitute of the incrassated aperture. 

 This species is closely allied to the genus Phos of Montfort, by the 

 striated labrum, and the projection or slight fold at the base of the 

 columella, which, in the system of that author, is an essential one. 



Nassa obsoleta. — Shell ovate-conic, subacute, cancellate, ex- 

 hibiting a granulated appearance, dark reddish-brown, or blackish, 

 sometimes tinged with olivaceous ; spire shorter than the body j 

 suture not deeply impressed ; beak not distinguished from the body 



