264 PROFESSOR OWEN ON THE EXTERNAL CHARACTERS 
mostly on the ground; and Mr. du Chaillu, in accordance with my inference from the 
state of the hair in the specimens which I had examined in 1859’, testifies that the 
male ‘‘ sleeps seated with his back against the tree-trunk.” 
The voice of the male Gorilla is a very loud ‘‘ barking roar :” ‘‘ it begins with a sharp 
bark, like an angry dog, then glides into a deep-bass roll like distant thunder along the 
sky, for which I have sometimes mistaken it when I did not see the animal. So deep 
is it, that it seems to proceed less from the mouth and throat than from the deep chest 
and vast paunch’®.” 
The capacity of chest, girdled by an extra pair of ribs, gives countenance to this 
testimony of the power and quality of voice. 
The female and young scream when alarmed, and the mother utters also a low kind 
of cluck to call or warn her young one. The Gorilla is not gregarious: it is mono- 
gamous: but one female is found with the male, and he is often companionless. 
‘* Young Gorillas I found sometimes in companies of five or less, but never more®*.”’ 
“The young always run off, on all-fours, shrieking with fear. They are difficult to 
approach, as their hearing is acute.” ‘‘The adult animal is also shy. When the 
mother runs off from the hunter, the young one grasps her about the neck and hangs 
beneath her breasts with its little legs about her body*.”’ 
The absence of the Lion in the Gorilla-forests leaves this powerful Ape the mastery 
of his habitat, if, indeed, his presence may not account for the absence of the so-called 
‘king of beasts.” 
The tracks of the Gorillas observed by Mr. du Chaillu showed that they went on all- 
fours, with evidence of occasional rest, as when tempted by wild sugar-cane or other 
favourite food ; and he describes it as the usual mode of progression. The body is carried 
half erect, the hind legs moved with a swing between the arms, as on crutches, and 
those somewhat bowed outward’ (Pl. XLIV. fig. 1). The hind feet leave no traces of any 
of the toes, except the great inner one or ‘ hallux.’ The broad impressions of the digital 
callosities of the fore-hand leave slight marks of their distinctness. When alarmed, 
the hind limbs take a greater share in flight; but the body is inclined forward, and no 
doubt the fore limbs assist in the more rapid movement. When progressing on the 
lower limbs only, the ‘‘ walk is a waddle from side to side:” these being somewhat 
inadequate to the proper support of the huge superincumbent body, he balances him- 
self by swinging his arms, or clasping them behind the head. 
When so pursued as to be driven to stand at bay, the Gorilla, like the Bear, raises 
himself on his hind feet, with his powerful arms and hands free for the combat. In this 
predicament Mr. du Chaillu affirms that the creature “‘ offers defiance by beating his breast 
with his huge fists, till it resounds like a bass-drum®.” There is nothing in the struc- 
* Proc. Zool. Soc., January 1859, p. 19. 
* Du Chaillu, ‘ Explorations and Adventures in Equatorial Africa,’ p. 70. * Ibid. 
“ Ib. p. 352. 5 Tb. p. 352. * Ib. p. 70. 
