2i2 THE DARWINIAN THEORY 



announcement from opposite sides of the world, were 

 causes for sincere congratulation. It was fortunate 

 for Darwin, in causing him to publish his views 

 more speedily, and in a more condensed and attractive 

 form than he originally purposed, and as leaving 

 him at liberty for further work. It was also for- 

 tunate for Wallace in securing cordial and sym- 

 pathetic recognition in the most gratifying manner 

 of his independent discovery. Finally, it was 

 fortunate for the world, and a lesson for all time to 

 come, of how an emergency, involving the tenderest 

 susceptibilities of scientific reputation, can be treated 

 so as to redound to the infinite and lasting credit of 

 all concerned. 



With regard to Wallace, it is interesting to know 

 the immediate causes which suggested the theory, 

 especially in view of Darwin's history, and I cannot 

 do better than quote Wallace's own words : 



"In February 1858 I was suffering from a rather 

 severe attack of intermittent fever at Ternate, in the 

 Moluccas ; and one day, while lying on my bed 

 during the cold fit, wrapped in blankets, though 

 the thermometer was at 88° Fahr., the problem 

 again presented itself to me, and something led me 

 to think of the ' positive checks ' described by 

 Malthus in his ' Essay on Population,' a work I 

 had read several years before, and which had made 

 a deep and permanent impression on my mind. 

 These checks — war, disease, famine, and the like — 

 must, it occurred to me, act on animals as well as man. 

 Then I thought of the enormously rapid multiplica- 

 tion of animals, causing these checks to be much 



