622 ZOOLOGY 
The orang-outaug 1s 1-38 metres (4-44 feet) high ; 1+ has 
twelve pairs of ribs, the same number as in man ; the arms 
are very long, reaching the ground, so that in walking they 
rest on their knuckles, swinging the body through their long 
arms as if walking on crutches ;-their posture is only par- 
tially erect. The forehead is less strongly marked than in 
Fig. 587.—The Chimpanzee, variety Tshego.—From Brehin’s Thierleben. 
the other apes, showing better the shape of the skull. The 
volume of the brain, both of the orang and chimpanzee is 
about twenty-six or twenty-seven cubic inches. The follow- 
ing table will show, according to Wyman, the relative 
capacity of the skull in the different apes as compared with 
man: 
