UNIVALVES. 



PLATE XII. 



Genus. STROMBUS. 



Character. Shell spiral : the cheek, or maxilla oris, turned outwards, and spread 

 out like a flap ; the cheek is also cut open and furrowed at the top and bottom, near 

 to where it joins the beak; the beak twisted inward and backward. 



Species. 



No. 1. Strombus quadratus. Shell white, richly streaked with brown ; outside 

 armed with tubercles ; mouth white, forming a striking and elegant con- 

 trast. It has been found only in the West Indies. 



No. 2. Strombus acutus. Shell white, but elegantly clouded with red marks ; 

 the mouth painted with red lines ; the channel in the bottom of the cheek 

 curiously twisted. A native of the Pacific Ocean. 



No. 3. Strombus Labiatus. Shell yellow, with an irregular spire ; mouth of a 

 rich purple, adorned with lines. Its native place unknown. 



No. 4. Strombus cornutus. Shell of a rich and gorgeous orange colour ; spire 

 ornamented with straight horns, closely placed in rows, forming a striking 

 and conspicuous effect. This shell has been obtained by our recent disco- 

 veries in the South Seas. 



No. 5. Strombus lentiginosus. Shell white, shaded with brown and purple 

 marks ; the cheek marked alternately with brown. Native place unknown. 



REMARKS. 



The genus Strombus presents a singularity of form and colouring not to be equalled by 

 any other family ; some are armed with amazing long horns, as the Strombus chiragra, 

 others plain and smooth ; it also contains a subdivision noticed by Lamark in his 

 Account of the Fossil Shells of France, in which the notch or channel at the bottom of the 

 cheek is always wanting ; but amongst the recent shells such a deviation has not yet been 

 noticed. These shells are generally thick and heavy, and natives of the warmer regions of 

 the globe ; they are remarkable for the gradual enlargement of the cheek, which increases 

 slowly in breadth and size as the animal advances in age. Upon the whole, this genus is 

 easily recognized, being distinctly marked by the peculiarity of the cheek, although the in- 

 dividuals differ much in other respects. 



