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Show 1890.] MARINE MOLLUSCA OF ST. HELENA. 275 OBELISCUS DOLABRATUS (Linne). Hab. West Indies ; Cuba, Guadeloupe, and St. Lucia (d' Orbigng) ; Island of Annabon, West Africa (Dunker) ; Red Sea; Indian and Pacific Oceans. Several specimens were dredged in shallow water, 5-20 fathoms, off the north of the island, and this I believe is the only record of the appearance of this species on the eastern side of the Atlantic with the exception of Annabon Island mentioned above. OBELISCUS SANCT^E-HELEN^E. (Plate XXIII. fig. 17.) Testa elongata, subpellucido-alba, linea flavescente interdum cincta, nitida, perforata ; anfractus normales 7, convexiusculi, mediocriter profunda separati; nucleus convexus, involutus; apertura inverse subauriformis ; columella recta, supra refiexa, superne plica valida instructa. Longit. 6| millim., diam. 2i. This species is characterized by being perforated, by its convexish smooth whorls, and the distinct twist or plait on the upper part of the columella. In most of the specimens at hand the slender coloured line which revolves round the middle of the body-whorl and up the spire, just above the suture, is very faint, but in a few fresher specimens it is much more distinct. Some examples which have the lip broken away, thus permitting a further view within the aperture, exhibit two very fine spiral plaits or lirae on the columella, below the uppermost stouter one. It becomes therefore a link, as it were, between the typical species of Obeliscus with three distinct folds on the columella, and Syrnola with only one, agreeing with the latter genus in general form and style of ornamentation. OBELISCUS (SYRNOLA) PUMILIO. (Plate XXII. fig. 3.) Testa elongata, gracilis, nitida, alba, lineis paucis spiralibus pellucidis ornata, lineaque unica rufescenti cincta ; anfractus leviter convexi, lente accrescentes, sutura simplici paulo sejuncti; nucleus globosus, pellucidus, obliquus, sinistrorsus apertura inverse subauriformis, basi vix effusa ; columella reflexa, superne plicata, inferne arcuata. Longit. 65 millim., diam. Ii. This species at first sight looks like a miniature of S. cinctella, A. Adams, from the Korea Straits. It is, however, proportionally more slender, the aperture is longer, and is ornamented with a few spiral pellucid zones. TURBONILLA HAROLDI. (Plate XXIII. fig. 18.) Testa elonqato-oblonga, alba, superne leviter coarctata ; anfractus 6, planiusculi, turriti, sutura profunda sejuncti, ad marginem superiorem incrassati, costis longitudinalibus suberectis, cequalibus (in anfr. ult. circiter 16-18) instructi, in interstitiis minute spiraliter striati; apertura inverse subauriformis, superne acuminata ; peristoma continuum, margine columellari |
