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Show 1885.] FROM THE SOLOMON ISLANDS. 589 Solomon Islands, has also been collected further north than Ugi, on San Christoval and Guadalcanar, by Macgillivray. 2. HELIX(NANINA) NITIDISSIMA. (Plate XXXVI. figs. l,\b.) Shell thin, transparent, very glossy, depressed, narrowly perforate, pale brownish horn-colour above, whitish towards the umbilicus, sculptured with very faint lines of growth. Whorls 4-5, slightly convex, impressed and marginate above at the suture; last whorl large, rounded at the periphery. Aperture obliquely lunate; peristome simple, thin, slightly thickened and reflexed partly over the perforation. Spire low, but very little raised above the last whorl, obtuse at the apex. Greatest diameter 14 millim., smallest 12; height 9. Hab. Treasury Island, Bougainville Straits. Nanina casca of Gould, from the Fiji Islands, is very like this species, but has more slowly increasing whorls : the last is proportionally smaller than in H. (Nanina) nitidissima. Two specimens from Guadalcanar Island, collected by J. Macgillivray during the voyage of H.M.S. ' Herald,' and presented by him to the British Museum, may be considered as referable to a variety of this species, having the spire somewhat more elevated and the body-whorl a little more globose. 3. HELIX (NANINA) SOLIDIUSCULA. (Plate XXXVI. figs. 2, 2 b.) Shell very narrowly perforate, depressed, somewhat solid, dark chestnut-brown and a little glossy above, more shining and paler beneath, becoming almost white at the umbilical region ; whorls 6^, convex, separated by a deepish suture, and, with the exception of two or three at the apex which are smooth, sculptured with strong, close-set, arcuate, and oblique striae on the upper surface, crossed with a few more or less distinct spiral lines. Body-whorl rounded at the periphery, or sometimes with the faintest indication of an angle, convex, and only exhibiting fine lines of growth below. Aperture obliquely semi-lunate ; peristome simple, but, owing to the solidity of the shell, seeming slightly thickened, especially on the very oblique columellar margin, which is shortly reflexed above over the perforation. Spire depressed-conoid, having the least convex outlines and an obtuse apex. Greatest diameter 18 millim., smallest 16|, height 12; aperture 8 long, 4\ wide. Hab. Santa Anna Islands, "living generally on the trunks of cocoa-nut palms" (Guppy). This species is well distinguished by its comparative solidity and strong sculpture on the upper surface. 4. HELIX (CORASIA) TRICOLOR, Pfeiffer. (Plate XXXVI. figs. 3, 3 b.) This species was described originally from specimens collected at the island of San Christoval; it was obtained at Ugi or Gulf |