184 Couthouy's Description of 
lished; arcuated, somewhat flattened, and its base 
turned rather abruptly to the left ; no umbilicus, oper- 
culum unguiculate, spire sub-terminal, stris of its pont 
coarse. 
Length seven-twentieths, diameter of bower whorl 
three-twentieths of an inch. 
Inhabits Massachusetts Bay. 
My own collection and that of the Boston Society of 
Nat. History. 
Osservations. A very distinct species, and not 
liable to’ be confounded with any shell found on our 
shores, unless it be Fusus Aarpulàrius, Nobis, pl. 1, fig. 
10. It pay; however, be easily distinguished from that 
shell by the greater convexity of its whorls, the absence 
of any flattening at the sutures, and the angular sinus at 
the junction of the lip ; as well as by its being white, 
instead of brown. In old shells the sutures are almost 
canaliculate, and the superior whorls considerably eroded. 
Three specimens were procured from. haddock, caught 
in March last, in about Sipen fathoms water, off Barn- 
stable, Gape- Cod. 
— — a: Say. 
Preis Shell sub-oval, rarely conical ; spire 
generally depressed ; aperture sub-orbicular or obovate, 
rounded at base ; base of the columella rounded or ob- 
tusely angulated ; columella wide, thickened, polished, 
generally with a callus near its: pite junction with 
the labrum. 
i 
