MUREX. ROCK-SHELL. 



Murex despectus. Donovan, pi. 31. 



Shell strong, thick, semltransparent, yellowish-white, 

 finely striate transversely, and very faintly so in a longitu- 

 dinal direction : spires seven or eight, much rounded and 

 swelling : aperture oval, dilated ; the outer lip thin, often 

 slightly notched by the outward striae; pillar rugged, and 

 a little twisted at the base ; canal reflected, open ; inside 

 yellowish-white : length sometimes six inches, and three 

 broad. 



Variety. With the volutions reversed. 



Lister, pi. 950. f. 44. b, and c. 



Lister marks this variety as English, observing that it 

 was found on the sea shore at Harwich, by Dr. Dale. 



The young shell, with the small end very abrupt and 

 rounded. 



Murex decollatus. Pennant, pi. 82. f. 3. 



A singular variety is in our cabinet, in which the volu- 

 tions are divided down to the very pillar by the line of se- 

 paration, as in the Turbo Clathrus : and at the junction be- 

 tween the first and second volutions, commencing from the 

 outer angle of the aperture, are three or four thin raised 

 longitudinal partitions, crossing the line of separation, and 

 forming distinct cells. 



In another variety the shell is strongly reticulated, of ^ 

 more taper shape, and furnished with six or seven much 

 raised and rounded longitudinal ribs, giving it a somewhat 

 angular appearance : probably the JM. fornicatus of Gme- 

 lin. v. v. 



6. Murex corneus. Horny Rock-shell. 



Lister, pi. 913. f. 5 Pennant, pi. 79. f. 2 Da Costa, 

 pi. 6. f. 5 Dorset Cat. pi. 17- f. 5 Donovan, pi. 38. 



Shell strong, elegantly taper, semitransparent, white, 

 "* mostly covered with a brown skin : spires eight or nine, 

 fiat and hardly raised, separated by a fine line ; finely and 

 regularly striate in a spiral direction, with a few obscure 

 longitudinal wrinkles on the body volution, and ending in 

 a fine point : aperture oblong-oval, terminating in a long 

 reflected canal, which together occupy about half the shell ; 

 outer lip thin ; inner lip spread on the pillar : length nearly 

 three inches j breadth one and a quarter. 



i 3 The 



