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Show 1893.] SPECIES O F T H E L A N D - M O L L U S C A N G E N U S ALYCEEUS. 595 on the swollen part of the last whorl, on the apical whorls it is close and fine ; colour ochre; spire somewhat flattened, apex blunt; suture deep; whorls 4, the last moderately swollen ; sharp constriction in front of sutural tube, followed by a strong ridge which is contiguous to the crenulate peristome; aperture circular, suboblique; peristome strongly crenulated, double; operculum horny, a large central excavated circular space, surrounded by a pale ring, well marked, rising above to the marginal portion. Size: maj. diam. 4*5; alt. axis 1*5 m m. The nearest known species allied to this is A. crenatus, oi the Khasi Hills, but the ridge behind the aperture in this last lies further back with a short interval; the peristome is not so strongly crenulate. A. plectocheilus oi Darjiling is a much smaller form. 7. ALYCEEUS DOHERTYI, n. sp. Locality. Momeit, Burmah (W. Boherty, in coll. Aldrich). Shell globosely turbinate, solid, not umbilicated; sculpture regular distant sharp costulation, closer and fine near the sutural tube; colour stone, with pink apex; spire rather high, conoid, rounded, apex blunt; suture impressed, the tube fine, rather long ; whorls 4|, the last swollen, constricted with a ronnded ridge midway between the sutural tube and the peristome; aperture expanded, ovate; peristome double, fine sharp crenulations on the outer margin, rounded on the inner. Size : maj. diam. 3-25; alt. axis 2*8 m m. This is quite a new form, partaking in the constriction and peristome of the characters oi A. plectocheilus, crenatus, &c. Momeit lies N.N.E. of Mandalay, about midway between it and Bhamo and further east than Mogok in the Ruby Mine District. 8. ALYCEEUS BUSBYI, n. sp. Locality. Nicobars (G. Busby, in coll. Dr. Hungerford). Shell turbinate, of tumid form, widely umbilicated; sculpture smooth, fine ribbing near the sutural tube and still finer below; colour pale ochraceous; spire moderately high, apex blunt; suture deep, the sutural tube short and thick ; whorls 4|, very rounded, the last much swollen and compressed within the umbilical cavity, constriction simple, slight; aperture oblique circular; peristome double, the outer lip flat and expanding at right-angles to the whorl. Size : maj. diam. 7*5 ; alt. axis 3*0 m m. This is the largest species as yet known from the Nicobar Islands. I name it after its discoverer, who gave the specimen to Dr. Hungerford; its exact locality has not been recorded. |