234 BERMUDA. 



and other species ' are exquisitely sculptured by 

 Italian artists in imitation of antique cameos, the 

 different strata of colouring matter resembling those 

 of the onyx and other precious stones. Of these, 

 a great variety of ornaments are made ; and of late 

 years a considerable trade has been carried on in 

 them on the Continent. 



We have a species very common in our bays, viz. 

 Cassis testiculus and Cassis Jlamnea. 



7. Genus Strombus. — The Strombi are distin- 

 guished generically from the right lip being much 

 dilated and entire, and by the canal at the base being 

 very short, truncated, or notched. Strombus gallus 

 is an example of the genus. The shell is turbinate, 

 tubercnlated, transversely sulcate, variegated with 

 white and red; the last turn crowned above with 

 large compressed tubercles. The tubercles are 

 united by a transverse ridge. Lip thin, extended 

 above into a long lobe. The animals of the Strombus 

 occasionally produce pearls. 



VII. Gasteropoda Tubulibranchiata. — Cuvier dis- 

 tinguishes these from the Pectinibranchiata, with 

 which, nevertheless, they have many aifinities, because 

 their shell, in the shape of a more or less irregular 

 tube, and only spiral at its apex, is permanently 

 fixed to other bodies. 



