UNIVALVES. 



PLATE XXXIII. 



Genus. CASSIS. 



Character. Shell ventricose ; spire short and pointed ; the mouth narrow, sinu- 

 ated, and denticulated on both sides ; the body and spire invested with angular 

 sutures, irregularly placed, alternate ; the lip thick, and strongly rounded. 



Species. 



No. 1. Cassis rotundata. The shell brown; the suture white, and placed in 

 front, spotted with black squares; back rounded, and ornamented with 

 small tubercles ; the same sutures repeated in the spire, which is angular 

 and acuminated. It is found upon the coasts of America and the West 

 Indies. Delineated from a shell belonging to Mr. Stutchbury. 



No. 2. Cassis alba. Shell white, highly polished, transversely spotted with dark 

 brown marks ; spire doubly reticulated in its folds, having also a continua- 

 tion of the sutures ; columella inclining to red ; the beak short, and bent 

 backwards. Native place unknown. 



No. 3. Cassis vamegata. Shell of a yellow brown colour, ornamented with red 

 longitudinal strise, placed in a waving form upon the body and spire, gene- 

 rally acuminate ; the mouth shaded with a yellow brown. Found in the 

 Eastern Seas. 



No. 4. Cassis labiata. Shell of a deep red, transversely striated with tubercu- 

 lous ridges and stripes ; the mouth large, of a rich orange colour, beautifully 

 striped with red, with a very thick lip, spreading over and covering the 

 shell ; the teeth small and numerous, investing both sides of the mouth. 

 This shell is frequently found at the Cape of Good Hope and in the 

 African Seas. 



REMARKS. 



The genus Cassis is so called from its resemblance, when viewed sideways, to the form of a 

 helmet, and is strongly distinguished from the genus Buccinum, by the narrow and straight 

 mouth, doubly denticulated, and the lips being so thickened as almost to form half the sub- 

 stance of the shell. The whole shell has a sort of triangular appearance, whichever way it is 

 placed. The angular lines carried up to the top of the apex distinguish it sufficiently from 

 the genus Cassidea, and also from the genus Conus, which has always a straight and plain 

 mouth. It bears a considerable resemblance indeed to the Strombus genus, with which it 

 has been obviously confused by some Writers, owing to some slight analogy of form and 

 character. Upon the whole, it may be regarded as a very ornamental shell, well calculated 

 to set off, by the strength of contrast and the boldness of its lines, others more graceful and 

 delicate in their structure. It is only found in the seas of the Torrid Zone. 



