DISTRIBUTION.--Inhabiting all Southern India, being conterminous with the _M. rhesus_ on the east and west coast, the latter species coming as far south as, and the Bonnet Macaque going no further north than, the Godaveri river on the one side and Bombay on the other. (See page 23.) HABITS.--The Bonnet Macaque agrees in habits with those of the species already described. It lives in troops in the forests and jungles everywhere throughout its range. It is much kept in captivity, owing to its docility and its wonderful powers of mimicry. THE MANGABEYS. GENUS CERCOCEBUS. _Cercocebus_, Geoffr., Ann. Mus., xix., p. 97 (1812). This genus has been established to receive a small, and but little known, group of Monkeys, which is confined to West Africa. They are nearly related to the Macaques on the one side, and even more closely to the genus _Cercopithecus_, next to be described, on the other side. They all have an oval head, and in form are more slender than the Macaques; they have also the muzzle less prolonged, the supra-orbital ridges less developed, the ischial callosities larger, and the limbs proportionately {37}longer. They agree with the Macaques, and differ from the _Cercopitheci_, or Guenons, in having a fifth hinder cusp to the posterior lower molar tooth in each jaw; and differ from both in the hairs of the body rarely being ringed with different coloured bars, as is the case with the species of both the genera just mentioned. The nose is situated behind the end of the muzzle. Their most obvious external character, however, and one from which they derive their common name of "White-eyelid" Monkeys, is their pure white upper eyelids, the white streak being more distinct on the inner half of the eyelid than on the outer. These Monkeys want the laryngeal air-sacs seen in the Macaques; but they have large cheek-pouches and a simple stomach, as in the latter. Their tail is always long, quite equalling the length of the body. The hands have a web between each of the fingers, that between the thumb and index finger being very short; in their feet, the great-toe, which is widespread, has a short web uniting it with its neighbour; the second and third toes are united nearly throughout their whole length, the fourth is webbed and united to the third and fifth as far as their mid-joints. The Mangabeys are confined to West Africa. Like their relatives, the Macaques and the Guenons, they are arboreal, living in troops in the forest country, and feeding chiefly on fruits. I. THE SOOTY MANGABEY. CERCOCEBUS FULIGINOSUS. _Cercocebus fuliginosus_, Geoffr., Ann. Mus., xix., p. 97 (1812); Gray, Cat. Monkeys Brit. Mus., p. 27 (1870); Schl., Mus. Pays-Bas, vii., p. 95 (1876). _Le mangabey_, F. Cuv., Hist. Nat., Mammif., livr. vi. (May, 1819). {38}_Simia fuliginosa_, F. Cuv., Mamm., livr. xxxv. (Dec., 1821). _Cercopithecus fuliginosus_, Martin, P. Z. S., 1838, p. 117.