MEANS OF THE EXPRESSION OF THE EMOTIONS. 297 



est degree tliat so mucli similarity, or rather identity 

 of structure, could have been acquired by independent 

 means. Yet this must have been the case if the races of 

 man are descended from several aboriginally distinct spe- 

 cies. It is far more probable that the many points of 

 close similarity in the various races are due to inheritance 

 from a single parent-form, which had already assumed a 

 human character. 



14 



