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Show 1899.] AND SPIDERS FROM TROPICAL WEST AFRICA. 857 tibia? of all with basal white band; protarsus of 1st and 3rd black, with basal band of 2nd and 4th white with black patch just beyond middle. Carapace with superior and lateral tubercles longer than in nodulosa. Abdomen (in type-specimen) not distended, its anterior portion low, nodular, not elevated. Vulva (as in figure Pl. LV1I. fig. 16) somewhat resembling that of nodulosa, the anterior portion completely divided into a right and left half by a deep median groove; the chamber containing the two fossa? smaller, more transversely oblong, with anterior rim less arched. Total length 15*5 mm., width of head 7*5 m m . Loc. Benito Biver (67. L. Bates). CJEROSTRIS TURRIGER, sp. n. (Plate LVII. figs. 15,15 a.) Colour. Dorsal surface of carapace, legs, and abdomen a tolerably uniform greyish brown, covered with a coating of yellow and white hairs intermixed; abdomen mottled with black spots and brownish patches and lines ; legs coloured as in C. albescens, but the distal spot on the protarsi reddish brown. Carapace with tubercles as in 0. albescens. Abdomen with its anterior portion elevated into a high, broad, subcylindrical prominence, the summit of which is about one third broader than long, with semicircularly rounded anterior tubercular border, and three large tubercles on the posterior border. Vulva as in figure (Pl. LVII. fig. 15 a). Measurements in millimetres.-Total length 16 ; width of head 7; height of abdomen from vulva to summit of prominence 13. Loc. Benito Biver (67. L. Bates); also young specimens of probably the same species from Sierra Leone (Surg.-Capt. Clements). Somewhat resembling G. petersi Karsch from Inhambaue (Mou. Ak. Berlin, 1878, p. 324, pl. i. fig. 7), in the elevation of the anterior portion of the abdomen; but in G. petersii the column is narrower, with the summit rounded and not encircled with tubercles. The three species of the genus known from the Benito Eiver may be diagnosed as follows :- a. Femora of legs bright red ; tibife of 2nd, 3rd, and 4th legs with scarcely a trace of basal white band; black underside of abdomen ornamented with three pairs of silvery spots ; upperside of abdomen velvety black, furnished with silvery lines and patches b. Femora steel-blue ; tibiae of 2nd, 3rd, and 4th legs with broad white basal band below; lower side of abdomen uniformly black, upperside dirty yellowish brown. a1. General colour of dorsal surface of body and legs white ; abdomen not elevated in front into a high thick column ft1. General aspect dirty yellowish brown; abdomen elevated in front into a broad thick column aryostictus. albescens. turriger. |