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assumed then that the hairy front of man’s ancestors became 
more completely coated when it became exposed to the elements 
equally as the back; and in that case the hair on the front— 
supposing it to have been as thick as on the back—is the more 
recent character so far as regards any great quantity. In 
retrogression the latest acquired characters disappear first. 
Following this law again, it may be assumed that the hair 
on the front, the insides of arms, and of legs disappeared first, 
then the hair from the limbs generally, then probably the hair 
from the face; while on the forehead, back, and scalp, the hair 
became very much reduced, but apparently there was a band 
of hair remaining over the ears and on the back of the head. 
Somewhere in the history of the human phylogenetic series 
these changes were probably spread over the life-time of 
individuals—the loss of hair from the chest and belly, which 
had once been an adult character,* had come, by the law of 
earlier inheritance, to belong say to late infancy; and the other 
changes followed, in order, to, say, late maturity. 
Then a change occurred.t For some reason—evidently 
the reason which makes the body and chest of an adult 
male become more hairy with advancing age at the present 
day—the scalp of Man became more hairy again. That the 
hair on the scalp has a different history to that at the sides of 
the head may be known because, when it reappears after the 
infant’s temporary baldness, it grows very considerably quicker 
than the hair at the sides, and soon passes that in length. A 
friend tells me that in some members of his family the hair on 
the scalp grows upright, whereas the hair at the sides of the 
heads grows in the usual manner—another piece of evidence to 
the same point. 
[ *In an adult Gorilla in the British Museum, and in an old Yellow Baboon 
in the Zoological Society’s Gardens, the chests are considerably denuded of hair. 
These facts also illustrate the law of retrogression. | 
{The following remarks only apply to our own race. Other races, though 
obviously progressing in the same manner, have not preserved the same relative 
proportional development of characters. 
. 
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