PLATE CIX. 



Murex carinatus, angukted. With five or six spires, the body ven- 

 tricose : the spires rising into angulated ridges. 

 The aperture semicircular. Length near four 

 inches. From the Portland Cabinet. Perm. 

 Br. Zool. T. 4. /;. 123. sp. 96. 



The shell figured in the annexed Plate is unique ; it formerly be- 

 longed to the late Duchess of Portland, by whose permission Mr. 

 Pennant described it in the British Zoology. This author has given 

 two figures of it, one in Plate 77, and the other in the Frontispiece 

 of the fourth volume. 



The existence of this species being only proved by a solitary speci- 

 men, various conjectures have arisen amongst Conchologists respecting 

 it. Some have been inclined to admit it as an undoubted species, and 

 others as a mere accidental variety of growth of the Linnasan Murex 

 Antiquus. How far we may be authorized to abide by the former 

 opinion must rest with the critical Naturalist- 



To argue that it cannot be a distinct species, because only one 

 shell of the kind has been hitherto found, is absurd ; since the ex- 

 istence of many other species has been asserted upon the evidence of 

 a single specimen only, and its relation to Murex antiquus is not so 

 obvious as might be at first imagined. It certainly approaches it in 

 the general outline, but the ridges of Murex Antiquus is most com- 

 pletely raised into tubercules, whereas those of Carinatus are per- 

 fectly smooth and even, nor is there that strict correspondence in 

 the angulations of the contour in general that should induce us to 

 consider it a vaiiery of Murex Carinatus. 



