206 



SHELLS AND SHELL-FISH. 



divisions would be species, and species only. We may 

 be pardoned, perhaps, for alluding to this great error in 

 our nomenclature more than once, because it appears to 

 us to be fraught with more inconveniences — not to say 

 evils — than those of an opposite nature ; and because, in 

 the group now before us, we have been obliged to name 

 and define so many new divisions. These divisions, in 

 fact, will show more forcibly than any general argu- 

 ments, the perfect confusion in which we must have 

 exhibited this portion of the Testacea, if we had left them 

 under the three or four genera where they now stand in 

 the latest systems of conchology. 



(189-) That the Turbines follow the Melaniancs is 

 evident from the close connection of Cerithidea Sav. 

 with Scalaria Lam. : the little basal channel of the former 

 gradually lessens in the aberrant species, until, in one we 

 possess from Florida, it is a mere vestige. This affinity 

 fixes the station of the sub-family before us better than all 

 theoretical reasons. The Turbince are all marine shells, 

 and possess a perfectly entire aperture. Their typical 

 genus, Turritella, is subulate, or awl-shaped, so as to have 

 the spire very long. All the TurbincB have their aper- 

 ture closed by an operculum, and their substance is never 

 perlaceous. From overlooking this very obvious diflPer- 

 ence,even in the shells, all conchologists, excepting Hum- 

 phrey, have blended them with the Trochidce. Cuvier, at 

 least, from the knowledge he had of the difference of the 

 animals, should have not fallen into this error : the con- 

 fusion has been still further increased by M. Ferussac ; for 

 he has given to the Turbines of Humphrey the new name 

 of Littorina, and transfers that of Turbo* to Humphrey's 

 Senectus. We do not usually trouble the reader with these 

 misnomers, but we shall correct them as they occur. Our 

 genus Turbo, therefore, is that of Linnaeus and Hum- 

 phrey, the last of whom we also follow in placing all the 

 perlaceous ones in that of Senectus. There are so few 

 variations or sub-genera in the Turbin.e, that we shall 



♦ The common winkle, Turbo littoreus Linn., is the type. 



