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Show 1881.] OF THE 'CHALLENGER' EXPEDITION. 275 HELIX (PATULA) STOKESI. (Plate XXIII. figs. 17-17 5.) Shell very depressed, moderately umbilicated, obtusely angled at the periphery, pale yellow, irregularly spotted and variegated with reddish subradiating markings above, and dotted and streaked beneath with a lighter tint. Whorls 6, the two apical smooth, glossy, the rest convex, separated by a deep suture, slowly increasing, sculptured with numerous arcuate radiating thread-like lirae ; last whorl obtusely angled or shouldered above the middle, and much more finely lirate beneath than above. Aperture obliquely lunate. Peristome thin, very slightly reflexed near the umbilicus. Greatest diameter 7\ millim., smallest 6\, height 4. This species very closely resembles //. coma of Gray, but is more narrowly umbilicated, just a trifle more finely lirate, and has the body-whorl roundly angulated above the middle. SANDWICH ISLANDS. Only the three following species, two Melanias from Honolulu and a Neritina from Hilo on the east coast of Hawaii, were brought home by the expedition. 1. NERITINA CARIOSA, Gray. The shell figured in Wood's Index Test. Suppl. pi. 8. f. 9, as Nerita cariosa is undoubtedly the species from the Sandwich Islands, and not the Mauritian N. mauritii as supposed by Von Martens (Conch.-Cab. ed. 2, Monogr. Neritina, p. 276). The type is still preserved in the British Museum, having formed part of the late Dr. Gray's private collection, which he a short time before his death presented to the Museum. It has the apex remarkably eroded, and but very little white speckling on the outer surface. Very little importance need be attached to the fact of its locality being given as Africa, for the next species but one, N. smithii, a well-known Indian form, is also stated to inhabit that locality. 2. MELANIA MAUIENSIS, Lea. This species has now been recorded from three of these islands (Maui, Molakai, and Oahu), and in all probability it occurs on Hawaii, the largest of the group. 3. MELANIA NEWCOMBII, Lea 1 I am rather uncertain whether the series of little shells from this locality really belong to this species. They are very slender, consist of about five moderately convex whorls (the apex being invariably broken away), which are coated with an earthy deposit, beneath which is a li"ht olive-greenish epidermis. They are sculptured with a few spiral striae, which become more or less obsolete upon the two last whorls except around the base of the last, where they are usually maintained. The length is 16 millim., width 5, and the aperture is 5 long and 3 wide. |