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Show 1871.] MR. HARPER PEASE ON POLYNESIAN LAND-SHELLS. 463 The above description was drawn up several years since from specimens collected at Kalapana, district of Puna, Island of Hawaii; as they have been lost, I furnish the precise locality, to enable collectors to recover the type. Before leaving this genus I would remark that, of the first type referred to above, three species have been described, viz. V. nitens, Pse., pediculus, Shutt, and nacca, Gld. They are widely distributed, specimens having been received from the following islands :-Apaiaug, Ebon, Upolu, Aitutake, Roratonga, Tahiti, Bolabola, Raiatea, Nuku-hiwa, Hawaii; they agree in their general characters as to size, shape, texture, and colour, with slight local variations. At some localities they are wholly dextral, at others wholly sinistral. They differ more widely as to the number and position of the teeth in the aperture : usually there are two teeth on the posterior wall of the aperture, which are separate or joined in a bifid manner, rarely but one; the columellar tooth is constant; on the base of the outer lip, generally three, at regular intervals, occasionally but two ; and in addition very small rudimentary teeth are rarely met with at different parts of the aperture. Having received but forty or fifty specimens, I am at present unable to offer a decisive opinion as to the value of the several species. I note also that V. tantilla, Gld., occurs on all the islands of the Tahitian group, and V. costulosa, Pse., on all those of the Hawaiian. The species of this genus will prove to be more widely distributed than those of any inhabiting Polynesia. Operculated Genera. Genus OMPHALOTROPIS, Pfr. Since the publication of a monograph of the above genus in 'Journ. de Conch.' 1869, a number of species have been described which confirm the distribution and variation as there given. The typical form of the genus, the shells of which are carinate or angulate around the umbilicus, more or less ornamented with colours, and of an ovate shape more or less modified, enters Western Polynesia from the East Indies, extending south to the Samoas and thence over the Papuan Islands. Passing east, however, to the Tahitian group and the other islands of Eastern and Southern Polynesia, the genus undergoes a wide variation, so much so that several of the species have been classed with other genera. Their operculum and animal clearly connect them with the above genus. One of the forms I have distinguished by the subgeneric name Scalinella, which may be found faithfully illustrated on Plate 7, Journ. de Conch. 1869. One remaining I now separate under the name of Subgenus ATROPIS, Pse. Testa oblonga, interdum cylindracea, rare ovata, imperforata vel anguste perforata, unicolor; apertura ovata, fere circularis |
