732 



MAMMALIA. 



with the hands reaching the ground. The skull is not prolonged into 

 a vertical crest. There is an os centrale in the carpus. The hallux is 

 well developed. They are the highest apes with hints of ischial callos- 

 ities. They are mainly arboreal in their habits. They feed on fruits, 

 leaves, shoots, eggs, young birds, spiders, and insects. Their voice is 

 powerful. As regards teeth, the gibbons are most like man. 



The Orangs (Simla) live in swampy forests in Sumatra and Borneo. 

 The males measure over 4 ft. They walk on their knuckles and 

 on the outer edges of the feet. The skull is prolonged into a vertical 

 crest. There are but slight supra-orbital ridges. The canines are very 



Fig. 322.- 



-Skull of gorilla. — From Edinburgh Museum 

 of Science and Art. 



large. There are twelve ribs as in man, and sixteen dorso-lumbar 

 vertebra. The larynx is connected with two large sacs which unite 

 ventrally. There are no ischial callosities. They are arboreal in their 

 habits, and make nests in the branches. They are exclusively vege- 

 tarian. As regards the structure of the brain, the Orangs are most like 

 man. 



The Gorillas ( Gorilla) live in Western Equatorial Africa. They are 

 larger than all other apes, and larger than man, though not over 54 ft. 

 in height. The arms reach to the middle of the lower leg, and "the 

 animals walk with the backs of their closed hands and the flat soles of 

 their feet on the ground. The skull is not prolonged into a vertical 



