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Show 1875.] LIEUT.-COL. BEDDOME ON NEW LAND-SHELLS. 445 OPISTHOSTOMA DISTORTUM, n. sp. Shell irregularly rhomboidal, pale-coloured, with an oblique rather distant costulation ; whorls 4, excentric, the upper one very minute and depressed, not visible from a side view, so that the shell appears as with only three convex whorls, second whorl moderate, third or penultimate much larger than the second or fourth, lowest whorl constricted as usual, and in front of the constriction deflected upwards, but uot concealing the umbilicus; aperture subangularly circular, pointing upwards, its apex in a line with the apex of the shell; peristome touching the upper part of the penultimate whorl, double, the lips not much dilated and with little space between them : total length -^ inch, greatest breadth -jL- inch. Golcondah hills, Vizagapatam, 17^° N. lat., elevation 3000 feet, rare; by far the smallest species yet known. Only one specimen was found, and this is now with Mr. Blanford, or has been mislaid; and the description is from notes and a rough drawing made at the time it was collected. CYATHOPOMA (JERDONIA) NITIDUM, n. sp. (Plate LII. fig. 12.) Shell inconspicuously umbilicated, pyramidal, turreted, smooth, shining, of a yellowish olive tint, apex rather obtuse, sutures deep, a very minute oblique striation is generally visible under the lens; whorls 5, convex, smooth, the lowest scarcely descending towards the aperture ; aperture circular ; peristome continuous, single, thin ; operculum double, thick, surrounded by a sulcate margin, externally very slightly concave ; the nucleus very large, half the diameter of the circle, very thin, transparent, shining, destitute of whorls, the outer portion externally shelly, internally membranaceous, furnished with an exquisitely close spiral sculpture : length of shell varying from T ^ to -J- inch, breadth of lowest whorl -^ inch. Anamallay mountains, 6000 feet elevation. South-Canara ghats, 4000 feet; a shell of very simple structure, closely allied to Cyclostoma trochlea, Bens. (Jerdonia, Blanford), but without any carina-tions, and a much smaller umbilicus; the operculum is very similar, but with a larger transparent nucleus and much more closelv wound. The operculum of Cyathopoma wynadense, procerum, and kolamal-liense, is very similar to that of this shell, only differing in being a little more concave externally ; so I propose that these species should be referred to Jerdonia, which, however, can, I think, only be kept up as a subgenus. The operculum of Mychopoma hirsutum and limbiferum is quite that of C. wynadense and its allies, and only thicker in proportion to the size ; there is the same transparent nucleus destitute of spiral whorls, and the same outer calcareous texture ; and they must, I think, also be referred to the Jerdonia section of Cyathopoma. The operculum of filocinctum, the type of Cyathopoma and its allies (i. e. deccanense, kalryenense, malabaricum, and conoorense), is at first sight very different; the margins of the outer shelly portion are much dilated and partially arched over, leaving a wide |