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Show 1887.] MOLLUSKS ON THE VITI ISLANDS. 299 the margins of mangrove-swamps. I also took many in similar stations at Wallis Island and Samoa. I have received it from New Caledonia, and, undoubtedly, it ranges throughout Melanesia. The locality "Gambier Islands," usually assigned to this species, is decidedly erroneous. There are no swampy lands and not a single perennial stream in the group. Schmeltz is also wrong in citing Huahine, Society Islands, as habitat. This species varies considerably in shape, thickness, and in size ranges from 12 to 30 millim. long. The surface is shining, longi-tudinally striated, and the upper portions of the whorls are sculptured by crowded spiral rows of minute granules, which, in large adults, sometimes cover the whole surface of the body-whorl. The lower part of the parietal region is armed with a prominent, compressed, oblique fold, and just beneath is a smaller and more vertical one on the columella. The peristome is rather strongly labiated and sinuous above. The shape of the shell varies from oblong-ovate to oblong-turreted, the spire is more or less produced, and the base imperforated. Colour white, beneath a fulvous-yellow or yellowish horn-coloured epidermis. Genus TRUNCATELLA, Risso. 1. T R U N C A T E L L A VALIDA, Pfeiffer. Truncatella valida, Pfeiffer, Zeit. Malak. 1846, p. 182; Mon. Auric. (Appendix) i. p. 184 ; Jav, Cat. Shells, 1854, p. 253; Kiister, Mon. p. 11, pl. 2. figs. 7, 8, 1*9-21, 23; H. & A. Adams, Gen. Moll. ii. p. 311 ; Martens, Ostas. Zool. ii. p. 262; Paetel, Cat. Conch, p. 118 ; Pease, Proc. Zool. Soc. 1871, p. 477. Truncatella vitiana, Gould, Proc. Bost. Soc. Nat. Hist. 1847, p. 208; Expl. Exp., Shells, p. 109, fig. 126; Otia Conch, p. 40; H. & A. Adams, Gen. Moll. ii. p. 311 ; Pfeiffer, Mon. Pneum. ii. p. 6; Mousson, Journ. de Conch. 1869, p. 356, 1870, p. 195; Paetel, Cat. Conch, p. 118; Schmeltz, Cat. Mus. Godeff. v. p. 104. Truncatella vitiacea, Mousson, Journ. de Conch. 1865, p. 185. Taheitia vitiana, Pease, Proc. Zool. Soc. 1871, p. 477. Truncatella conspicua, " Bronn," Pfeiffer, Mon. Auric. (Appendix) i. p. 184 ; Paetel, Cat. Conch, p. 118; Layard, Cat. Land & Freshwater Shells N. Caled. p. 1. This species occurs in abundance in all parts of the group, and lives just above high-water mark in sheltered places. It occurs also in the Samoa, Tonga, and Ellis group, and is diffused throughout Australasia and the East-India Islands. It may be characterized by its solid texture, slightly tapering cylindrical form, white, luteous, corneous, or ruddy corneous colour, and 4 | slightly convex persistent whorls. The sculpture consists of nearly erect, obtuse ribs (25 to 35) on the body-whorl, and the base is more or less distinctly carinated. The peristome is thick, slightly expanded and auriculated at the suture. The operculum is thin, convex, smooth, with an elastic lamina-like margin. Length 6 to 8 millim. |