422 ■ LECTUEE XIV. 



with greater difficulty the more distinctly the characters are 

 impressed by the stamp of time. 



The chaos of raceless animals^ which have not yet received 

 this stamp, exists not merely in races but in wild species, and 

 it will be worth the zoologist^s while to bear this idea in mind, 

 in the classification of wild animals and species. When I con- 

 sider the numerous varieties and species assumed in, for in- 

 stance, the South American genus Cebus ; when we see that 

 every naturalist differently conceives and differently groups 

 the numerous alhed forms, the conviction obtrudes on me that 

 we have before us a raceless multitude which oscillates between 

 different centres, Hke the multitude of raceless half-tamed or 

 wild dogs of the East, between the old pure races or species. 



But when we consider the conduct of the so-called species 

 and races on the whole, we constantly observe an important 

 difference, which does not prevent us from establishing some 

 few generally valid laws. Just as there are species which re- 

 main the same in all zones and have undergone no change in 

 the course of thousands of years, so are there again other spe- 

 cies which, transported into other climates, are essentially 

 transformed. The one may be said to be composed of unyield- 

 ing, the other of flexible materials. In the same way do we 

 observe species, as far as history can trace them, despite of 

 their resemblance, dwelling side by side without intermixture, 

 preserving the same peculiarities, without giving rise to a 

 mongrel race. Other species, on the contrary, which at a re- 

 mote period were perfectly distinct species, intermixed, pro- 

 duced prolific mongrels, and formed raceless masses, common 

 root stocks, so to speak, giving rise to new races and species. 

 Finally, there may be other species, which, though originating 

 from such common root-stocks, departed from them, and ac- 

 quiring distinct characters, became hostile to their brothers. 



That similar processes take place within the human genus, 

 and human races^ I shall endeavour to show in my next lecture. 



