498 ` The Making of Man. — [June, 
-The actual result in all these cases seems to depend largely on 
the comparative length of the arms and legs. All the three spe- 
cies named have shorter legs and longer arms than man, and can 
thus readily lift their bodies upon their arms while in a semi-erect 
` attitude. Yet they all are obliged to incline the body forward in 
movement. This is less the case with the gibbons, the extreme 
length of whose arms enables them to reach the ground with the 
hands without bending the body. Thus the gibbons can walk on 
the four limbs with the body erect. 
Certain species of the gibbon can readily walk erect on their 
legs alone by balancing themselves with their arms. They often 
do so, and can even move tolerably fast, the body rocking from 
side to side. But if urged to speed they drop their long arms to 
the ground and progress in the swinging fashion, Of the other 
forms there is no satisfactory evidence that the orang ever walks 
erect, though it may be able to assume the erect attitude when 
attacked. Mr. Savage says that the chimpanzees are sometimes 
seen walking erect, the body bent forward, with the hands clasped 
over the occiput to balance. But on the appearance of danger 
they immediately take to all fours to fly. 
The gorilla seems more inclined to walk erect, or rather in an 
_ down. And it stoops less, when on all fours, than the chimpanzee, 
since its arms are longer. When walking it balances its huge 
body by flexing its arms upwards. Its gait is a rolling one, from 
side to side. When attacked it seems to always assume the erect 
` posture. In structural formation it is better fitted to the erect 
attitude than is the gibbon. me 
The subject here considered is of considerable importance byt 
yf 
= ? that the walking gibbons or the gorilla might in time become 
true bipeds if they should completely give up their arboreal 
and legs, than in man. The species from which man desc 
_inclined position, the body bending forward, with the head hung > 
~ -its relation to the evolution of man. We observe various phases 2 
of tendency towards the biped habit, and can readily pr 
arms differs, but in all it is longer, as compared with the body — 
z 2 
: : residence, The length of the arms is an important element in ; 
_ this problem. In all the species mentioned the length of the 
with its longer legs and shorter arms than in the existing P. o 
poid apes, could not, without the greatest difficulty, have adopte? = 
their swinging mode of motion. Nor could it advantageously oe ` 
