37G 



BRANCH CHORDATA 



firoiiiid to aid in walking tlicy rcsi, ..,,.m the hack of the knuckles. Cheek 

 ])i)ucli('s and tail arc lackiiifi and the hair is more scaiiiy than in the baboons. 

 These entirely Old World forms have a verniiforni a|)|)endix. 



The gibbons {IJ i/lnh'dlcs), slender, nionkey-iike Indo-Mahiyan forms, 

 stand at the base of the series. They are tlie smallest an<l most arboreal 

 and their arms are the lon^;est of any of the firouj), beinti lon^ enough 

 to reach the ground even when standing erect. The ranines are large in 

 hot h sexes and t he jaws and nose are prolonged. The lirain is simpler than 

 in t he higher forms. One of the most remarkable habits is tluur tleseending 

 flight t hrough the trees, though they never come to the ground. They leai) 

 incredible distances, says Hornaday, catch and swing with their hands, catch 

 again with their feet, turning again, and so on, by a series of revolutions 

 almost as fast as the flight of a bird. The largest is the Sumatran Siamang, 

 which stands 3 feet tall and is shining black. The gray gibbons are very 

 timid, but show strong affection for their young and great courage in their 

 defense. 



299. Comparison of skeletons of pri 

 chimpanzee; 4, gorill 



ites: 1, Cibbon; 2, orang; 3, 

 "), man. 



The brown orang-utan lives in Horneo and Sumatra, wholly in the 

 tree-tops, coming to the ground only for water. On the ground it moves 

 slowly and swings its body along between its arms like a pair of crutches. 

 In the trees, too heavy for leaping, they swing underneath the branches with 

 their long arms, "grasping a limb with their hook-like hands, and swinging 

 underneath to the next hold, and so on, at great s]khm1."' It subsists upon 

 wikl fruits, fleshy leaves, and shoots of the screw pine. It is shy and uncer- 

 tain if captured. When young it is easily tamed; when grown, wild and 

 ferocious. Hornaday says "in 1901 the zoological i)ark contained four 

 orangs, all of which were" taught to wear clothes, sit in chairs at table, eat 

 with fork and spoon, drink from cups and bottles, and ])erform many human- 

 like actions without nc rvousiu^ss in the ])resence of two thousand visitors. 

 Elach of the orangs learned its i)art in about two weeks' training, and at the 



1 Ingersoll. 



