6o2 MAMMALS. 



males are very large. The cervical vertebrae bear very high neural 

 spines, on which are inserted the muscles which support the heavy skull. 

 There are thirteen ribs, and seventeen dorso-lumbar vertebrze. There 

 is no OS centrale in the carpus. There are no ischial callosities. They 

 live in families in the forest, and feed on fruits. As regards size, 

 the gorillas are most like man. The males are much larger than the 

 females. 



The Chimpanzees (Anthropopithectts) live in Western and Central 

 Equatorial Africa. They do not exceed a height of 5 feet. The arms 

 reach a little below the knee. They walk on the backs of their closed 

 hands and on their soles or closed toes. The skull has no high crests. 

 The supra-orbital ridges are distinct. The canines are smaller than in 

 Gorilla or Orang. There is no centrale in the carpus. There are no 

 ischial callosities. They live in families in the forest, and are chiefly 

 arboreal, making nests in trees. They seem to feed on fruits. In the 

 sigmoid curvature of the vertebral column the chimpanzees are most 

 like man. 



Family 5. Hominidse. Genus Homo. 



The distinctiveness of man from his nearest aUies de- 

 %)ends on his povyer of building up ideas and of guiding 

 his conduct by ideals. But there are a few structural 

 peculiarities of some interest. 



Man alone, after his infancy is past, walks thoroughly 

 erect. Though his head is weighted by a heavy brain, it 

 does not droop forwards. With his upright attitude, the 

 perfect development of vocal mechanism is perhaps con- 

 nected. 



Man plants the soles of his feet flat on the ground ; the 

 great, toes are often longer, never shorter than the others, and 

 lie in a line with them ; he has a better heel than monkeys 

 have. No emphasis can be laid on the old distinction 

 which separated two-handed men (Bimana) from the " four- 

 handed " monkeys (Quadrumana), nor on the fact that men 

 are peculiarly naked. But " the arms are shorter than the 

 legs, and, after birth, the latter grow faster than the rest of 

 the body." 



Compared with the anthropoid apes, man has a bigger 

 forehead, a less protrusive face, smaller cheek-bones and 

 supra-orbital ridges, a true chin, and more uniform teeth 

 (2, 1, 2, 3), forming an uninterrupted horse-shoe shaped series 

 without conspicuous canines. 



