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Show 1890.] MARINE MOLLUSCA OF ST. HELENA. 283 CYPR,EA SPURCA, Linne. The distribution of this species is similar to that of the preceding, excepting that it also occurs at the West Indies (d'Orbigny and others). The single shell received from Mr. Melliss, and named C. turdus by Jeffreys, is merely a small specimen of C. spurca. LITTORINA MILIARIS, Quoy and Gaimard (var.). Hab. Ascension Island (Q. & G.) ; also R. Trimen and Dr. Conry in British Museum. The specimens from St. Helena do not agree exactly with those from Ascension. In them the last whorl is rather less ventricose ; the spire longer, and consequently more acutely conical; the aperture is a trifle more effuse at the base, and the tuberculation much less pronounced; indeed, in some instances, the surface is all but smooth. Jeffreys and Melliss have classed the St. Helena forms under the name of L. striata, King, but, in my opinion, they are certainly more closely related to L. miliaris. In connexion with this species I would observe that L. granulans, Gray, and L. nodosa, Reeve (not of Gray), are synonymous. Some remarks by Watson (Voy. 'Challenger,' Rep. Gasteropoda, p. 5/6) and Lischke (Japan. Meeres-Conch. ii. p. 70) have been given concerning tbe synonymy of L. granularis. After a very careful comparison of Gray's much worn type with specimens of L. miliaris from Ascension, I feel convinced of their identity; but I rather incline with Lischke to hold Dunker's L. exigua, from Japan, as distinct from L. granularis, Gray, with which it is united by Watson. It is not surprising that Lischke should consider Reeve's L. granularis a distinct species from Gray's, seeing that the latter author's type is in such worn condition, so that neither the colour nor sculpture could be accurately described; and, moreover, it was from an unknown locality. The very young specimens from St. Helena have quite a different aspect from the adult Ascension examples, having an angular body-whorl and an effuse columella at the base; still, in a large series of different ages, the transitions or links are observable. LITTORINA HELENiE, Melliss. (Plate XXI. fig. 19.) Littorina helence, Melliss's St. Helena, p. 125. Testa parva, trochiformis, fusco-nigra, inferne regionem versus umbilici pallidior; spira elevata, conica, acuta, lateribus recti-linearibus; anfr. 8, plani, seriebus granulorum tribus ornatt, striisque intercalatis paucis sculpti; anfr. ultimus subacute angu/atus, ad angulum serie tuberculomm duplici instrucius, inferne liris concentricis tenuibus ductus; apertura parva, rotunde quadrata, longit. totius f-^ adcequans, intus saturate castanea, linea basali albida interrupta; columella pallida, inferne castanea et subacuminate effusa. Longit. 9 millim., diam. fere 6. Among the shells presented to the British Museum by Mr. Melliss » |