Lamarck's Genera of Shells. 55 



columella, and is generally loaded with small, oblong, wrinkled 

 tubercles, lying in a transverse direction, which assist in forming 

 the character of these marine shells. 



Type. Cassidaria echinophora. (Buccinumechinophorum. Linn.) 

 Shell ovate-globular, ventricose, banded, striated above and be- 

 low, pale yellow ; bands, four or five in number, tubercular ; whorls 

 of the spire angular ; angles tubercular-crenate. Mediterranean. 

 PI. v. Fig. 187. 5 Recent species, and 2 fossil. 



2. Cassis*. 



Shell inflated. Aperture longitudinal, narrow, terminated at its 

 base by a short canal, curved abruptly towards the back of the 

 shell. Columella plaited, or wrinkled transversely. Right lip 

 almost always toothed. 



This genus is included by Linneus in his Buccina, from which it 

 is distinguished by the longitudinal direction and narrow form of 

 the aperture, by the right lip being toothed, by the flattening of 

 the left or columellar lip, which generally projects considerably on 

 that side, and by the abrupt reflection of the base of the canal to- 

 wards the back of the shell. The true buccina have no canal, but 

 merely a notch at the base of the aperture. 



The spire of the cassis is but little elevated, and often interrupted 

 by oblique cariniform varices. Lamarck uses these varices to di- 

 vide the genus into two sections, those shells whose spires are fur- 

 nished with them constituting one section, and those which are not, 

 the other. 



Type. Cassis glaucat. (Buccinum glaucum. Linn.) 

 Shell ovate, turgid, smooth, gray ; the last whorl anteriorly sub- 

 angular ; spire striated, papillous, pointed ; lip with four teeth at 

 the base, internally brownish yellow. Indian Ocean, Pi. v. 

 Fig. 188. 25 Recent species, and 1 fossil. 



2nd Subdivision. 

 An oblique notch, inclining backwards. 



* A helmet. 



t Gray. Lamarck's sixth species ; bis type is C, mudvgascariensis. 



