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Show 310 MR. ANGAS ON A NEW GENUS OF LAND SHELLS. [Mai*. 5, SlCYONIA FURCATA, sp. n. (Plate XVII. fig. 4.) This species, in the form of the body, closely resembles Sicyonia ocellata, Stimpson (Proc. Ac. Nat. Sci. Phil. p. 43, 1860), of which young specimens from Hong Kong, presented by the Smithsonian Institution are in the British-Museum collection, and also one fully adult from Ceylon, presented by E. W . H. Holdsworth, Esq. As in S. ocellata, the dorsal carina is very convex and strongly dentate, the cephalothorax tomentose, and the first to sixth postabdominal segments deeply channelled and without spines on the lateral margins. The terminal segment, however, is of very different form, being furcate at the extremity, the lobes of the fork divergent, acute at apex and deeply channelled above, the inner and outer margins carinate and ending in small subterminal spines on each lobe of the fork. In S. ocellata the last postabdominal segment is simple and acute at apex. Hab. Sooloo Islands. A single adult example is in the collection. This specimen, and also those of S. ocellata that I have seen, appear to be of the female sex. EXPLANATION OF PLATE XVII. Fig. 1. Peneeus hardwickii (p. 300), lateral view, natural size. 1 a. Terminal segment and uropoda of the same, natural size. 2. Peneeus dobsoni (p. 302), lateral view of cephalothorax, natural size. 2 a. Mandible, magnified. 2 b. Second maxilla, magnified. 2 c. First maxillipede, magnified. 2 d. Second maxillipede, magnified. 2e. Third maxillipede, magnified. 2f. Part of the ventral surface of the cephalothorax of a male individual, showing the form and position of the fifth pair of legs (from a specimen lent by Prof. J. Wood-Mason, see note p. 303). 2g. The same view of a female, showing the rudimentary and indurated condition of the fifth pair of legs. 3. Exognath of the mandible of Aristeus edwardsianus (p. 308), natural size. 4. Sicyonia furcata (p. 310), lateral view, natural size. 4 a. Terminal segment and uropoda of the same, magnified. 4. Description of a new Genus of Land Shells belonging to the Family Cyclophoridae. By G E O R G E F R E N C H A N G A S, C.M.Z.S., F.L.S., &c. [Received Feb. 16, 1878.] Genus MASCARIA, Angas. Operculum horny, ovate, pointed above ; whorls few ; nucleus situated near the base of the columellar margin. Shell rimate, elongately ovate, conically turreted, nearly smooth or faintly longitudinally striated ; aperture ovate, rounded below aud angulate above ; peristome continuous, single ; outer lip thickened and slightly expanded. |