ONISCIA 



TESTiV oblonga, subcylindrica, apice obtusiuscula, 

 basi acuminata : Spird brevi ; aperturd elongate, 

 basi in canalem brevissimum desinente; labio eoc^ 

 term subincrassato, intern^ denticulato, mediant 

 subcoarctato, inferno expanse, granuloso. ^ 



A Genus sufficiently distinguished from Cassidaria, by its 

 granulated inner lip^ its very short, scarcely reflected 

 canal, and its very singular general form. We should 

 have hesitated to separate it from Cassidaria, had we 

 been acquainted only with th6 species named by Linneans 

 Strombus Oniscus, but as three other species are known, 

 one a fossil, another the elegant shell which holds the 

 most conspicuous place in our plate, and the third nearly 

 related to Oniscus, we have adopted the Genus under the 

 name of Oniscia. Its place in a natural system is next 

 to Cassidaria, to which it is most nearly related j it does 

 not appear to us to be at all related to Strombus, and 

 though placed in that Genus by Linne, it has not its 

 principal characters. It differs also from Cassis in the 

 canal not being suddenly reflected, although we remem- 

 ber to have seen Cassides which very nearly approach 

 this in the form of the aperture, and in the short, scarcely 

 reflected canal, so that we think this may be considered 

 as the intermediate Genus between Cassidaria and Cassis, 

 always remembering that there is no difficulty in distin- 

 guishing it from the latter, which has always a reflected 

 canal, and the base of its columella sharp edged. 



Shell oblong, subcylindrical, apea; generally rather 

 obtuse, sjnre short, sometimes very short 3 base rather 



