Semnopithecus (Colobus) olivaceus, Wagner, in Schreber's Säugeth. Suppl., i., p. 309 (1840).
Colobus cristatus, Gray, Ann. and Mag. N. H. (3), xvii., p. 77 (1866); id., P. Z. S., 1886, p. 182, pl. xv.; id., Cat. Monkeys Brit. Mus., p. 19, et Suppl., p. 128 (1870).
Procolobus verus, Rochebr., Faun. Sénég., Mamm. Suppl., p. 97, pl. 1 (1887).
Characters.—Body stout; limbs robust; head oval, the muzzle slightly prominent; face and ears naked, brownish-black; thumb entirely absent; callosities large. Hair on the top of the head, forming a median crest, reddish-olive; whiskers, directed backward, pale yellow; over the eyes a frontal bar of the same colour, coalescing with the whiskers opposite the eyes; upper part of body to base of tail and down to the knees, covered with short dark olive-brown hair, finely ringed with black, and washed with rufous on the back of the neck and on the outside of the thighs; the tail long and thin, olive-brown or brownish-grey; shoulders, flanks, and outer surface of the limbs, pale greyish-green; upper sides of the hands and feet reddish-brown; throat, chest (the hair of which is elongated), under surface of the body and inner side of the limbs, ashy-grey. Length of body, 21 inches; of tail, 24¼.
Distribution.—West Africa. Forests of Fanti and Ashanti.
II. THE RED-CRESTED GUEREZA. COLOBUS RUFOMITRATUS.
Colobus rufomitratus, Peters, M. B. Akad. Berl., 1879, p. 829, pl. iA. and ii.
Tropicolobus rufomitratus, Rochebr., Faun. Sénég., Mamm., Suppl., p. 102 (1887).
Characters.—Body thick-set and covered with short hair; face and ears naked and brownish-black, the long superciliary hairs and the transverse crest, from ear to ear, black; front and back of the head to the nape of the neck brownish-red; cheeks and chin dark grey; back, from the nape of the neck, flanks, outer and hinder surfaces of the limbs, and the feet, dark brownish-olive; front of the shoulder, of the arm and part of the fore-arm, and the front of the thighs, pale reddish-yellow; breast, under side of the body and inner side of the limbs, of the same colour, but paler; tail coloured like the back, the tip tufted, brownish-black. Length of body, 26¾ inches; tail, 27¾.
Distribution.—This very rare species lives in East Africa. Forests at Muniuni, near Mombasa.