328 THE STORY OP THE EARTH AND MAN. 



admitted tliat no case has been ascertained in wMch 

 an individual of one species has transgressed the 

 limits between it and other species. However ex- 

 tensive the varieties produced by artificial breeding, 

 the essential characters of the species remain, and 

 even its minor characters may be reproduced, while 

 the barriers established in nature between species by 

 the laws of their reproduction, seem to be absolute. 



With regard to species, however, it must be 

 observed that naturalists are not agreed as to what 

 constitutes a species. Many so-called species are 

 probably races or varieties, and one benefit of these 

 inquiries has been to direct attention to the proper 

 discrimination of species from varieties among animals 

 and plants. The loose discrimination of species, and 

 the tendency to multiply names, have done much to 

 promote evolutionist views ; but the researches of the 

 evolutionists themselves have shown that we must 

 abandon transmutation of true species as. a thing of 

 the present; and if we imagine it to have occurred, 

 must refer it to the past. 



Another gap is that between the nature of the 

 animal and the self-conscious, reasoning, moral nature 

 of man. We not only have no proof that any animal 

 can, by any force in itself, or by any merely physical 

 nfluences from without, rise to such a condition; 

 out the thing is in the highest degree improbable. 

 It is easy to affirm, with the grosser materialists, that 

 thought is a secretion of brain, as bile is of the 

 liver; but a moment's thought shows that no real 



