The wrist (_carpus_) contains but eight bones, as there is no central (_os centrale_) bone, a character in which it agrees with Man and the Chimpanzee, but differs from the Orang. The volume of the brain in the largest Gorilla rarely exceeds 34½ cubic inches, which is only half the capacity of the human skull. It may be safely said that an average European child, of four years old, has a brain twice as large as that of an adult Gorilla. The weight of a healthy human brain never falls below 31 ounces; that of the largest Gorilla has probably never reached 21. (_Huxley._) In the brain of the Gorilla the cerebellum can be seen between the deep longitudinal fissure which separates the two halves of the cerebrum. It agrees in this with the Orang and _Anthropopithecus calvus_--the latter exhibiting even a greater divergence of the cerebral lobes. The young male Gorilla differs much from the adult; its central cranial crest is less prominent than the occipital ridge for the neck muscles. The female is much smaller than the male, but the cheeks are relatively broader; the cranial crests and ridges are less strongly marked, and the canines shorter and less powerful. Her breasts are long and pointed, not globular. The height of the adult male Gorilla is over six feet, but the female rarely exceeds four feet six inches. The general colour of the Gorilla is black or blackish; the whole skin of the face is glossy, set with a few hairs, and deep black; the crown reddish-brown, sometimes of a dark brown, the hairs being dun-coloured at the root, grey in the middle, {184}and dark brown at the tip; on the sides of the face the hair is dark brown or black, grey at the root; on the neck and shoulders the hair is grey at the root, and lighter towards the point. The back, the region of the humerus, and the thighs are brownish, the hair being pale grey at the root, blackish-brown further up, and dark grey at the termination; the fore-arms, the hands, ankles, and feet, dark brown or black; round the posterior is a circle of white hair in some, in others of brownish-yellow. Old individuals become grey or grizzled. DISTRIBUTION.--Western Equatorial Africa, between the Cameroons and the Congo. This region presents a variety of hill and dale; the uplands are clothed with forest, and the dales are covered with grass and low bush, with abundance of fruit-yielding trees.