1890.] MARINE MOLLUSCA OF ST. HELENA. 291 



acuminata, intiis rufescens ; columella rejlexa, fusco ti)icta, 

 superne lahro juncta ; labrum vix incrassatum, pallidum. 

 Longit. 2h millim., diam. fere 1|. 



This species is considerably like B. rubra of the British coast. It 

 is, however, of a stumpier form, the spire being less produced, and 

 the body-whorl longer in proportion to the spire. 



CjEcum jucundum, de Folin. 



C jucundum, de Folin, Fonds de la Mer, vol. i. p. 20, pi. 2. 

 figs. Ch 7. 



Hab. Guadeloupe. 



C>BCUM TMBRTCATTi>r, Carpputer. 



('(fciim imhricatum, Carp. Proc. Zool. Soc. IS.iS, p. 4'22. 



Hab. West Indies. 



C^cuM (Meioceras) nitidum. Bean. 



Meioceras nitidum (Bean), Carp. P. Z. S. 1858, p. 4iJ8. 



Hab. W. Indies. 



Cerithium (Bittium) gibberultjm, var. 



Cerithium gibberulum, C. B. Adams Proc. Bost. Soc. N. Hist. 

 184.5, vol. ii. p. 5 ; Sowerby, Thes. Conch, vol. ii. p. 87G, pi. 184. 

 figs. 210, 211 ; id. Reeve's Conch. Icon. pi. 18. fig. 123. 



Hab. Jamaica. 



The specimens from St. Helena are much paler than those from 

 the West Indies. The varix on the back of the body-whorl is 

 whitish in all, and usually has some short brown lines on the trans- 

 verse lirse behind it, and a dark brown spot in front. 



Triforis perversa (Linne). 



Hab. Mediterranean, North Sea, English Channel, Atlantic coasts 

 of France and Portugal, North-west Africa and Madeira, Canary 

 Islands and the Azores. 



The specimens from St. Helena are as variable in form as those 

 from other localities, some being very much more slender than others. 

 The minute bead-like granules are pale in colour, and contrast 

 strongly with the rich brown dots between them. The central row 

 of granules on the penultimate and preceding volutions is almost as 

 large as the others in the majority of the specimens. 



Triforis melanura (C. B. Adams). 



Cerithium melnnura, C. B. Adams, Contrib. Conchol. p. 117. 



Hab. Jamaica. 



A few specimens of a whitish colour, with the exception of the 

 four apical whorls and tiie cauda of the last, which are brown, 

 possibly belong to this species. For the most part, however, tiiey 

 have the central spiral series of granules on the penultimate and one 

 or two preceding whorls rather finer than the others. In other 

 resjiects they accord with Adams's description. 



