_Cercopithecus melanogenys_, Gray, Ann. and Mag. Nat. Hist., xvi., p. 212 (1845); id., P. Z. S., 1849, p. 7, pl. ix., fig. 2; id., P. Z. S., 1868, p. 182; id., Cat. Monkeys Brit. Mus., p. 21 (1870); Scl., P. Z. S., 1860, p. 246; Monteiro, P. Z. S., 1860, p. 112; Jentink, Notes, Leyden Mus., x., p. 11 (1888); Sclater, P. Z. S., 1893, p. 245. _Cercopithecus picturatus_, Santos, Journ. Sci. Lisb., xi., p. 98 (1886). CHARACTERS.--The white nose-spot cordate in shape; a band across the forehead above the eyes passing backwards over the ears, and over the lower cheeks, black; region between the eye and the ear whitish; back finely grizzled with black and orange; centre of the back washed with deep rufous; outside of the legs dark grey, becoming black on the hands and feet; tail dark rufous. Length of body, 15¾ inches; tail, about 17 inches. The black lower cheeks, and the white region between the eye and the ear distinguish _C. melanogenys_ from _C. nictitans_ and _C. stampflii_. DISTRIBUTION.--West Africa: Angola. "It is very abundant at Encôge, three days' journey to the south of Bemba." (_Monteiro._) {50}VIII. STAMPFLI'S GUENON. CERCOPITHECUS STAMPFLII. _Cercopithecus melanogenys_, Schl., Mus. Pays-Bas, vii., p. 90 (1876, nec Gray). _Cercopithecus stampflii_, Jentink, Notes, Leyden Mus., x., p. 10 (1888); Sclater, P. Z. S., 1893, p. 257. CHARACTERS.--Nose-spot white, with its broader part lowest, and the point upwards; crown of head, nape of neck, legs and hinder portion of tail black; spot on lower lip black; chin, breast, anterior portion of belly, and inside of fore-arms white; forehead, cheeks, back, sides of body, and the basal portion of the tail, rufous-green, the hairs being ringed with black and rufous-yellow. Length of body, 25¼ inches; tail, 38½ inches. Distinguished from _C. nictitans_ by its white under surface. DISTRIBUTION.--West Africa: Liberia. Obtained in the Pessi country by Messrs. Büttikofer and Stampfli. IX. SCHMIDT'S GUENON. CERCOPITHECUS SCHMIDTI. _Cercopithecus ascanias_ (?), Scl., P. Z. S., 1887, p. 502. _Cercopithecus schmidti_, Matschie, Zool. Anz., p. 161 (1892); Sclater, P. Z. S., 1893, p. 245, pl. xvi. CHARACTERS.--Closely allied to _C. melanogenys_, the white nose-spot cordate. Face and superciliary region blue; nose above the white spot black; a bar between the nose-spot, reaching to the whiskers, on each side, black; upper and lower lips flesh-coloured; whiskers white, conspicuous, and with a very narrow black streak on their lower edge; beard white; above the superciliary region, and between the flesh-coloured ears, a black frontal bar; top of head, back, outer aspect of arms, thighs, and of the basal third of tail, olive-green and more {51}punctulated than in _C. melanogenys_; throat, under side of body, and inner side of the upper part of the limbs, white; fore-arms, hands, legs, and feet black; posterior two-thirds of tail rufous.