110 BOOK OF SPECIES. 



** Columella callous. 



B. ARCULARTA. Ovatc - conic^ ventricose, 

 thick, ash-colour (somethnes zoned with pale 

 fulvous); body- whorl turgid, crowned with sharp- 

 ish tubercles, and grooved below ; whorls flattened 

 above, strongly plaited longitudinally, and grooved 

 transversely ; lip crenated below, striated within, 

 and the throat zoned with reddish brown, 1^; 

 the middle of the body- whorl is smooth. W. 

 22. 40. 



B. coRONATUM. Ovate-acute,thickish, smooth, 

 but striated at the base, somewhat olive- coloured, 

 with obscure bands, or sometimes entirely of a 

 sallow white, with pure white longitudinal streaks ; 

 upper margin of whorls tuberculated ; lip towards 

 the bottom armed with spinous denticles; striated 

 within. 1. W. 22. 41. 



B. GiBBOSULUM. Ovate,backgibbous,smooth, 

 whitish or olive ; spire short, acute ; callus ex- 

 tremely large, edged with orange, and extending 

 to the apex; lip smooth. |. W. 22. 46. 



B. NERiTEUM. Orbicular, flattened, smooth, 

 tawny white, somewhat mottled ; pillar-lip obso- 

 letely dilated, and thickened ; last whorl sub-an- 

 gular ; spire extremely obtuse ; diam. f . W. 22. 

 48. 



EBURNA. 



Shell oval or elongated; lip perfectly simple; aper- 

 ture longitudinal} emarginate at base ; columella 



