310 MR. ANGAS ON A NEW GENUS OF LAND SHELLS. [Mar. 5, 



Sicyonia furcata, sp. ii. (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 fur- 

 cate 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 £. ocellata the last postabdominal segment is simple and acute at 

 apex. 



Ilab. 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. Penaus hardwickii (p. 300), lateral view, natural size. 



1 a. Terminal segment and uropoda of the same, natural size. 



2. Penaus dobsoni (p. 302), lateral view of cephalothorax, natural size. 



2 a. Mandible, magnified. 



2 b. Second maxilla, magnified. 



2 c. First maxillipede, magnified. 



'2d. Second inaxillipede, magnified. 



2 e. Third maxillipede, magnified. 



2/. 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 Aristcus edwardsianus (p. 308), natural 



size. 



4. Sicyonia furcata (p. 310), lateral view, natural size. 



4«. Terminal segment and uropoda of the same, magnified. 



4. Description of a new Genus of Land Shells belonging to 

 the Family Cyclophoridse. By George French Angas, 

 C.M.Z.S., F.L.S., &c. 



[Eeceived Feb. 16, 1878.] 



Genus Mascaria, Angas. 



Operculum horny, ovate, pointed above ; whorls few ; nucleus situ- 

 ated near the base of the columellar margin. 



Shell rimate, elongately ovate, conically turreted, nearly smooth 

 or faintly longitudinally striated ; aperture ovate, rounded below and 

 angulate above ; peristome continuous, single ; outer lip thickened 

 and slightly expanded. 



