2S92 LAY SERMONS, ADDRESSES, AND 'REVIEWS. [xii, 



independently, and yet professing to have discovered one 

 and the same solution of all the problems connected with 

 species. The one of these authors was an able naturalist, 

 Mr. Wallace, who had been employed for some years in 

 studying the productions of the islands of the Indian 

 Archipelago, and who had forwarded a memoir embody- 

 ing his views to Mr. Darwin, for communication to the 

 Linnsean Society. On perusing the essay, Mr. Darwin 

 was not a little surprised to find that it embodied some 

 of the leading ideas of a great work which he had been 

 preparing for twenty years, and parts of which, contain- 

 ing a development of the very same views, had been 

 perused by his private friends fifteen or sixteen years 

 before. Perplexed in what manner to do full justice 

 both to his friend and to himself, Mr. Darwin placed 

 the matter in the hands of Dr. Hooker and Sir Charles 

 Lyell, by whose advice he communicated a brief abstract 

 of his own views to the Linnsean Society, at the same 

 time that Mr. "Wallace's paper was read. Of that abstract, 

 the work on the " Origin of Species " is an enlargement ; 

 but a complete statement of Mr. Darwin's doctrine is 

 looked for in the large and well-illustrated work which 

 he is said to be preparing for publication. 



The Darwinian hypothesis has the merit of being 

 eminently simple and comprehensible in principle, and 

 its essential positions may be stated in a very few 

 words : all species have been produced by the develop- 

 ment of varieties from common stocks by the conversion 

 of these first into permanent races and then into new 

 species, by the process of natural selection, which 

 process is essentially identical with that artificial selec- 

 tion by which man has originated the races of domestic 

 animals — the struggle for existence taking the place 

 of man, and exerting, in the case of natural selection, 



