THE PAST EVOLUTION OF MAN 71 



vindicated by the results ; and the evolutionist may 

 be permitted to quote the educative value of the 

 hand in the individual as corroboration of his theory 

 that it has played an important part in the education 

 of the race. 



This naturally leads us to the consideration of 

 the last anatomical difference between man and 

 the anthropoid that need be discussed. Others 

 there are, such as that distinctively human struc- 

 ture known as the chin, but they are of scant 

 significance. This last anatomical difference is a 

 difference — or rather, a series of differences — in 

 brain -proportion. 



"We have already observed that there is scarcely 

 any difference in brain-structure between man and 

 his cousins. 1 The human and the anthropoid brain 

 correspond, convolution for convolution, fissure for 

 fissure. But the correspondence is very far from 

 being merely anatomical. It is also physiological 

 — a fact of much profounder significance. As 

 every one knows, recent study has enabled us to 

 allocate various functions to various areas of the 

 brain. One part of a certain convolution controls 

 the muscles of the arm ; another area is concerned 

 with the sight ; another with hearing, and so forth. 

 The correspondence between the human and the 

 anthropoid brain in these respects is simply amaz- 

 ing. Indeed the greater part of our knowledge of 

 what is called " cerebral localisation " in man has 

 necessarily been derived from study of the ape. 

 Since we can experiment upon the ape but not 



1 His cousins, not his ancestors. This most important distinction 

 will later be discussed. 



