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Show 1884.] OF T H E ' C H A L L E N G E R ' EXPEDITION. 265 does not probably indicate the full dimensions attained by the species, for it has the appearance of being rather young. 5. HELIX (HEMIPLECTA?) CARTERETI. (Plate XXII. figs. 5, 5 a.) Shell narrowly perforate, rather solid, depressedly conical, fulvous brown above, rather paler beneath. Whorls 7, moderately convex, slowly enlarging, divided by a deepish suture, sculptured with oblique lines of growth and very minute microscopic spiral striae; last whorl with an obtuse keel at the periphery, somewhat wrinkled beneath, peculiarly contracted a little behind the aperture ; the latter narrowly lunate, flesh-tinted within, subhorizontal. Peristome strong, not reflexed or expanded, slightly dilated over the perforation. Spire shortly conical, with faintly convex outlines. Greatest diameter 22 millim., smallest 18J, height 15. Hab. Wild Island. This is a very distinct form, remarkable for the peculiar pinched character of the last whorl a little behind the aperture. H. nova-hibernia has a faint resemblance to it, but is more regular in growth, brown-banded above the periphery, with a different form of aperture. I have named the species after Capt. Carteret, who discovered this group of islands in 1767. 6. HELIX (CHLORITIS) DENTRECASTEAUXI. (Plate XXII. figs. 6, 6 b.) Shell depressed, narrowly umbilicated, light brown, marked with fine lines of growth, and everywhere finely punctate, and probably pilose in a fresh condition. Spire slightly suuken below the body-whorl. Volutions 5, convex above, separated by a deepish suture, slowly enlarging; the last somewhat inflated, a little descending anteriorly, having two indentations-one, elongate, about the middle of the whorl, at a short distance from the lip, the other nearer the labrum, just under the base, both forming denticular prominences within. Aperture oblique, narrowly lunate. Peristome whitish, thickened, reflexed everywhere, the extremities being united by a thin callosity spreading over the whorl. Greatest diameter 17 millim., smallest 14, height 10. Hab. Wild Island. This remarkable species is readily distinguished from its allies by the peculiar indentations on the body-whorl forming within the aperture pseudo-denticles. As compared with Pfeiffer's figure of II. eustoma (Novitat. Conch, ii. pi. 38. f. 3-5), also from the Admiralty Islands, it will be seen that this species has a more depressed spire, a narrower umbilicus, and a narrower aperture. 7. PARTULA HARTMANNI. (Plate XXII. fig. 7.) Shell elongate, conical, thin, semipellucid, white, narrowly umbilicated. Whorls 5|, slightly convex, sculptured with minute microscopic spiral striae and fine oblique lines of growth, which give the upper edge of the whorls a slightly puckered appearance; last |