II GORILLA AND MAN : SKULL 105 



long and narrow passage the coarse, out>vardly 

 curved, ischiatic prominences on which the Gibbon 

 habitually rests, and which are coated by the so- 

 called " callosities," dense patches of skin, wholly 

 absent in the Gorilla, in the Chimpanzee, and in 

 tbe Orang, as in Man ! 



In the lower Monkeys and in the Lemurs the 

 difference becomes more striking still, the pelvis 

 acquiring an altogether quadrupedal character. 



But now let us turn to a nobler and more 

 characteristic organ that by which the human 

 frame seems to be, and indeed is, so strongly dis- 

 tinguished from all others, I mean the skull. 

 The differences between a Gorilla's skull and a 

 Man's are truly immense (Fig. 17). In the former, 

 the face, formed largely by the massive jaw-bones, 

 predominates over the brain-case, or cranium 

 proper : in the latter, the proportions of the two 

 are reversed. In the Man, the occipital foramen, 

 through which passes the great nervous cord con- 

 necting the brain with the nerves of the body, is 

 placed just behind the centre of the base of the 

 skull, which thus becomes evenly balanced in the 

 erect posture ; in the Gorilla, it lies in the posterior 

 third of that base. In the Man, the surface 01 

 the skull is comparatively smooth, and the supra- 

 ciliary ridges or brow prominences usually project 

 but little while, in the Gorilla, vast crests are 

 developed upon the skull, and the brow ridges over- 

 hang the cavernous orbits, like great penthouses. 



