88 APES AND MONKEYS 



undergo the same change. In very aged specimens the 

 outer part of the hair often assumes a dirty, brownish 

 color. This is due to the want of vascular action to sup- 

 ply the color pigment. The same effect is often seen in 

 preserved specimens, for the same reason that the hair of 

 an Egyptian mummy is brown, though in life it had been, 

 doubtless, a jet black. In this ape the hair is uniformly 

 black, except the small tuft of white at the base of the 

 spinal column and a few white hairs on the lower lip and 

 the chin. I have examined about sixty living specimens, 

 and I have never found any other color among them, 

 except from the cause mentioned. The normal color of 

 both sexes is the same. The kulu has, as a rule, but 

 little hair on the top of the head ; but that on the back 

 of it and on the neck is much longer than elsewhere on 

 the body, and on these parts it is longer than that on 

 other apes. 



Much stress is laid by some writers on the bald head 

 of one ape and the parted hair on the head of another. 

 These features cannot be relied upon as having any spe- 

 cific meaning, unless there are as many species as there 

 are apes. Sometimes a specimen has no hair on the crown 

 of the head, while another differs from it in this respect 

 alone by having a suit of hair more or less dense ; and 

 yet in every other respect they are alike. Some of them 

 have their hair growing almost down to the eyebrows, and 

 all hairs appear to diverge from a common center, like the 

 radii of a sphere ; another of the same species may have 

 the hair parted in the middle as neatly as if it had been 

 combed ; another may have it in wild disorder. The same 



