CANALIFERA. MOLLUSCA. PD8U8. 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 despSctus. 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- 

 trdrius 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. dead. Jfat. Sc., v. 214. 

 Fusus carinatus, KIKNER ; 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- 



