360 BACKBONED ANIMALS. 
that, in this genus, are augmented by a large sac in the 
throat that communicates with the larynx, which when 
1, gibbon; 2, orang; 3, chimpanzee; 4, gorilla; 5, man. 
(After Huxley.) 
Fic. 379.—Comparison of skeletons of primates : 
filled with air is distended like a huge goitre in the neck. 
The “ylobates agilis is remarkable for its leaps, clearing 
