DARWIN'S THEORY. 31 



should sometimes occur in the course of thousands of 

 generations? If such variations do occur, can we doubt 

 (remembering that many more individuals are born 

 than can possibly survive), that individuals, having an 

 advantage, however slight, oyer others, would have the 

 best chance of surviving and procreating their kind?" 

 "If," he continues, "a man can, by patience, select 

 variations useful to him, why, under changing and 

 complex conditions of life, should not variations, use- 

 ful to nature's living products, often arise and be pre- 

 served and selected?" 



Darwin asks, " What limit can be put to this power, 

 acting during long ages, and rigidly scrutinizing the 

 whole constitution, structure, and habits of each crea- 

 ture — favoring the good and rejecting the bad?" "I 

 can see no limit to this power, in slowly and beautifully 

 adapting each form to the most complex relations of 

 life." 



"Selection," continues Darwin, "will pick out, with 

 unerring skill, each improvement. Let this process go 

 on for millions of years, and may we not have a low 

 primordial type" continuing to evolve into higher and 

 still higher forms of life, until, at last, as the result of 

 this "innate tendency to vary," producing improve- 

 ments, and of this Natural Selection preserving these 

 improvements,, all of the higher animals, including 

 Man, are successively evolved, by the gradual opera- 

 tion of strictly natural processes? In this way, Dar- 

 win contends, the present development, and diversity 

 of structure, of the several species, have been effected; 

 and in this way "some one low primordial form into 



