OCR Text |
Show 1890.] MARINE MOLLUSCA OF ST. HELENA. 291 acuminata, intus rufescens; columella reflexa, fusco tincta, superne labro juncta ; labrum vix incrassatum, pallidum. Longit. 2| 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. C.ECUM .TUCUNDUM, de Folill. C. jucundum, de Folin, Fonds de la Mer, vol. i. p. 20, pi. 2. figs. 6, 7. Hab. Guadeloupe. CECUM IMBRICATUM, Carpenter. Ccecum imbricatum, Carp. Proc. Zool. Soc. 1858, p. 422. Hab. West Indies. CECUM (MEIOCERAS) NITIDUM, Bean. Meioceras nitidum (Bean), Carp. P. Z. S. 1858, p. 438. Hab. W. Indies. CERITHIUM (BITTIUM) GIBBERULUM, var. Cerithium gibberulum, C. B. Adams Proc. Bost. Soc. N. Hist. 1845, vol. ii. p. 5 ; Sowerby, Thes. Conch, vol. ii. p. 876, 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 transverse lira., 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 melanura, 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 the cauda of the last, which are brown, possibly belong to this species. For the most part, however, they have the central spiral series of granules on the penultimate and one or two preceding whorls rather finer than the others. In other respects they accord with Adams's description. |