CANALIFERA. MOLLUSCA. FUSUS. 287 



deed he does the M. despectus of Linnaeus also ; and the figure of 

 Donovan in his " British Shells," vol. v. pi. 180, under the name of 

 Murex despectus. I have very little doubt that it is the genuine M. 

 despectus of Linnaeus ; but as another shell is now universally received 

 under that name, it seems the most judicious way to apply a new 

 name to this, with the above explanation. 



This shell probably never becomes three inches in length. It is in- 

 elegant and coarse, in general smooth and somewhat shining, though 

 seeming to be made up of small, plane surfaces, rather than curved 

 ones. The elevated lines are broad, and smoothly rounded, of a 

 darker color than the rest of the shell, and give it an appearance as 

 though it might have been turned in a lathe, but left in an unfinished 

 state. In general outline it very strongly resembles the fossil F. con- 

 trarius of the English crag formation. 



Fusus DECEMCOSTA'TUS. 



Shell ova/, turreted, ash-colored, with ten elevated, rounded, 

 horn-colored ribs on the lower whorl, and two on the upper ones. 



FIGURE 202. 

 State Coll., No. 18. Soc. Cab., No. 314. 



Fusus decemcostatus, SAY ; Journ. Acad. Nat. Sc. t v. 214. 

 Fusus carinatus, KIENER ; Species, (Fusus) pi. 19, f. 1. 



Shell obliquely oval, narrowed at both ends, solid, coarse, 

 spire elevated and turreted, ash-colored, composed of about six 

 convex whorls, coarsely wrinkled by the lines of growth ; lower 

 whorl turgid, and girdled by about ten broad, elevated, rounded 

 ribs or keels, of a light reddish horn-color ; they are about equi- 

 distant, the posterior one is the largest, and the successive ones 

 go on diminishing, till, about the beak, they become nearly ex- 

 tinct ; between the posterior rib and the suture is a broad, exca- 

 vated shoulder, giving the shell a turreted appearance ; the two 

 largest ribs revolve also on all the upper whorls ; the space be- 

 tween the ribs is marked by fine revolving lines ; aperture ovate ; 

 outer lip sharp, and modified by the termination of the ribs ; inner 

 margin regularly arched, and thinly spread with white enamel ; 

 the pillar, at its lower third, twists outwards to form a short, curved 

 beak, and has, at this part, an imperfect umbilicus, bounded ex- 



