VERTEBRATA: MAMMALIA. 



7 8l 



and the Gorilla (71 Gorilla), with some other imperfectly 

 known forms. The Chimpanzee is a native of western Africa, 

 extending its. range eastwards to Abyssinia ; and has the arms 

 much shorter, proportionately, than in the Gibbons and 

 Orangs ; still they are much longer than the hind-limbs, and 



Fig. 453. A, Skull of the Orang-utan. B, Skull of an adult European. 



they reach beneath the knee when the animal stands erect. 

 The ears in the Chimpanzee are large, and the body is covered 

 with dark-brown hair. The animal can stand erect, but the 

 natural mode of progression is on all-fours. The hands are 

 naked to the wrist, and the face is also naked, and is much 

 wrinkled. The Chimpanzee lives in society in wooded dis- 

 tricts, constructs huts, and can defend itself against even the 

 largest of its foes. 



The Gorilla is in most respects the same as the Chimpan- 

 zee, but is much larger, attaining a height of between five and 

 six feet. The hind-limbs are short, and the ears are small. It 

 is an enormously strong and ferocious animal, and is found in 

 Lower Guinea and in the interior of equatorial Africa. It 

 possesses a laryngeal sac, has a most appalling voice, and is 

 polygamous. Its habits are mainly arboreal, and the male 

 builds a kind of nest in the trees, in which the female brings 

 forth the young. The Gorilla has been often regarded as the 

 most human of the Anthropoid Apes, but many of the highest 

 authorities believe that the Gibbons have a greater claim to 

 occupy this position. 



As regards the distribution of the Quadrumana in time, the 

 earliest representatives of the order appear to be found in the 

 Eocene Tertiary. In deposits of this age in Wyoming, Pro- 

 fessor Marsh has discovered several forms apparently related 



