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Show 1879.] SHELLS FROM PERAK AND THE NICOBAR ISLANDS. 739 vertical; the columellar margin perpendicular, with usual Peristome double, slightly sinuate on the outer margin, viewed from side. Size, alt. 0*054, diam. 0*03 in. (G.-A.). Perak. (Indian Museum, Calcutta.) DIPLOMMATINA (PALAINA) MIRABILIS, n. sp. (Plate LX. figs. 4, 4a, 4b.) Shell dextral, solid, elongately pyramidal; colour pale umber-brown ; sculpture regular ribbing in high relief: this costulation on the basal side is not continuous up to the columellar margin, but the epidermal layer terminates on a defined line level with the upper angle of the aperture and encloses thus a lunular smooth area very characteristic of this species. Spire rapidly decreasing, sides flat, apex pointed, suture well impressed. Whorls 7, the penultimate tbe largest, sides convex. Aperture subvertical, straight on the outer margin, broadly ovate ; columellar margin straight, the tooth of flattened form. Peristome continuous, closely double. Size, alt. 0*07 inch, maj. diam. 0*04 in. (G.-A.) Perak. Of this very distinct and beautifully formed shell only one specimen was found. It presents characters which show a decided departure from the subgenus Palaina; and no doubt other allied species will eventually be found in this area. DIPLOMMATINA (PALAINA) SUPERBA, n. sp. (Plate LX. figs. 5, 5a.) Shell sinistral, elongately pyramidal, very solid; colour ruddy ochre; sculpture fine close costulation, waved on the periphery of the last whorls, tbe apical whorls smooth. Spire very pointed, suture deep. Whorls 7*3, last very angular, almost keeled ; the antepenultimate the broadest; the penultimate the most swollen. Aperture large, circular, very oblique. Peristome much thickened, widely double; the inner lip continuous; the outer angular on the outer margin, rounded below. Size, alt. 0-094, maj. diam. 0-06 in. (G. A.) Perak. This is a very beautiful small species of Palaina; only one specimen was obtained. (Indian Museum, Calcutta.) Diplommatina (Palaina) nevilli (Crosse, Journ. Conch, t. xix. p. 205, pi. viii. f. 2), Lagocheilus townsendi (Crosse, I. c. p. pi. viii. f. 3), and Alyceeus perakensis (Crosse, /. c. p 206, pi. f. 7) were also obtained by Dr. Townsend. GEORISSA MONTEROSATIANA, n. sp. (Plate LIX. fig. 6.) Testa parva, sat tenuis, imperforata, fulva ; apice leevi, conspicue prominent e ; anfract. 5, convexi, celeriter concentrice confertimque sulcati, sulcis minutis et regularibus, |