PENTADACTYLUS. 129 



but the operculum has a lateral nucleus like that of the 

 other genera in this sub-family. 



Species of lopas. 



hederacea, Mart. situla, Reeve. 



sertum, Lam. 



Genus VEXILLA, Svi^ainson. 



Shell purpuriform ; inner lip flattened and depressed; 

 outer lip, when adult, thickened, inflected, and toothed ; 

 aperture wide. 



Ex. V. vexillum, Chemnitz, pi. 13, fig. 5. 



Species of Vexilla. 



liueata, A. Adams. vexillum, Chem. 



tfeniata, Powis. 



Genus PENTADACTYLUS, Klein. 



Shell ovate, solid ; spire short, whorls tubercular or 

 spinous; aperture linear, narrow, contracted by callous 

 projections, with an oblique emarginate canal in front; 

 inner lip wrinkled ; outer lip internally with plait-like 

 teeth, often digitate. 



Spn. Ricinula, Lam. Drupa, Bolt. 



Ex. P. globosus, Martini, pi. 13, fig. 6. Operculum, 

 P. elegans, Broderip, fig. 6, a, G, h. Shell, P. grossula- 

 rius, Bolten, fig. 6, c. 



The shells of this genus, usually known under the 

 Lamarckian name of Ricinula, may be distinguished by 



VOL. I. s 



