XXV] PBIMATES 713 



cerebellum is not completely covered by the cerebrum. Simla is 

 represented by a single species, 8. satyrus, the Orang-utan, a large 

 animal about 4j feet high, which is found in the islands of Borneo 

 and Sumatra. This animal walks on two feet supporting itself on 

 its knuckles. It lives however almost entirely in trees, constructing 

 a sort of nest for itself out of branches (Fig. 360). It is remarkable for 

 its high rounded cranium enclosing the large brain, which presents 

 the closest approximation to the human brain of all the brains of 

 Apes. The cranium is however still small compared to the bones 

 of the face and lower jaw. Of the next genus Gorilla only a single 

 species exists, viz. G. savagei, confined to a limited region of Equa- 

 torial Africa. This is the largest of all the apes, reaching a height 

 of 5J feet. It is distinguished from Simla by its shorter arms and 

 more receding forehead. The skull of the young Gorilla strikingly 

 resembles a child's skull, but in the adult it is deformed by the 

 development of great bony ridges which give attachment to the 

 muscles of the face (Fig. 358). Anthropopithecus is represented 

 only by A. troglodytes, the Chimpanzee, which lives in Western 

 Africa in the same region as the Gorilla, but has a wider distribution. 

 It is distinguished by its shorter arms, which do not reach below 

 the knee, and by its smoother and rounder skull. It does not 

 reach a height of more than 5 feet and is on the whole the most 

 Man-like of all the Simiidae, though each of the other species of 

 the family approaches more closely to the human standard in some 

 particular feature and the Chimpanzee is more purely arboreal in 

 its habits than the other Simiidae. 



Man is distinguished above all by the great size of the brain, 

 which is double the size of that of the highest Monkey, and by the 

 modification of the leg so as entirely to support the body, in 

 consequence of which the big toe is no longer used for grasping. 

 Some hold that it was this latter modification which brought about 

 the great development of the intelligence of Man, arguing that 

 when once the hand was entirely at the service of the brain the 

 varied uses to which it could be put would give the opportunity for 

 the use of the mind. This seems probable, but the great factor 

 which has stimulated the mental development of Man is his habit 

 of living together in societies and undertaking concerted enterprises 

 for the benefit of the community. To this power of combination not 

 only intellect but also language and morals may eventually be traced 

 back. Man did not make society, it was society that made Man. 

 The general circumstances of the Evolution of Man are becoming 



