PERPETUATION OF LIVING BEINGS. 117 



in nature ! Indeed, I do not know that it is possible 

 by direct evidence to prove the origin of a variety in 

 nature, or to prove selective breeding ; but I will tell 

 you what we can prove — and this comes to the same 

 thing — that varieties exist in nature within the limits 

 of species, and, what is more, that when a variety has 

 come into existence in nature, there are natural causes 

 and conditions, which are amply competent to play 

 the part of a selective breeder; and although that is 

 not quite the evidence that one would like to have — 

 though it is not direct testimony — yet it is exceeding 

 good and exceedingly powerful evidence in its way. 



As to the first point, of varieties existing among natural 

 species, I might appeal to the universal experience of 

 every naturalist, and of any person who has ever turned 

 any attention at all to the characteristics of plants and 

 animals in a state of nature ; but I may as well take 

 a few definite cases, and I will begin with Man himself. 



I am one of those who believe that, at present, there 

 is no evidence whatever for saying, that mankind 

 sprang originally from any more than a single pair ; 

 I must say, that I cannot see any good ground 

 whatever, or even any tenable sort of evidence, for 

 believing that there is more than one species of Man. 

 Nevertheless, as you know, just as there are numbers 

 of varieties in animals, so there are remarkable varie- 

 ties of men. I speak not merely of those broad and 

 distinct variations which you see at a glance. Every- 

 body, of course, knows the difference between a Negro 

 and a white man, and can tell a Chinaman from an 

 Englishman. They each have peculiar characteristics 

 of colour and physiognomy; but you must recollect 



