6 Daruin- Wallace Celebration. 



am happy to say, has never been doubted, is that the idea of 

 what is now termed " natural selection " or " survival of the 

 fittest," together with its far-reaching consequences, occurred 

 to us independently, and was first jointly announced before 

 this Society fifty years ago. 



But, what is often forgotten by the press and the public, is,. 

 that the idea occurred to Darwin in October 1838, nearly 

 twenty years earlier than to myself' (in February 1858) ; and 

 that during the whole of that twenty years he had been 

 laboriously collecting evidence from the vast mass of literature 

 of Biology, of Horticulture, and of Agriculture ; as well as- 

 himself carrying out ingenious experiments and original 

 observations, the extent of which is indicated by the range of 

 subjects discussed in his ' Origin of Species/ and especially 

 in that wonderful store-house of knowledge his 'Animals 

 and Plants under Domestication/ almost the whole materials 

 for which works had been collected, and to a large extent 

 systematised, during that twenty years. 



So far back as 1844, at a time when I had hardly thought 

 of any serious study of nature, Darwin had written an outline 

 of his views, which he communicated to his friends Sir Charles 

 Lyell and Dr. (now Sir Joseph) Hooker. The former strongly 

 urged him to publish an abstract of his theory as soon as 

 possible, lest some other person might precede him but he 

 always refused till he had got together the whole of tho 

 materials for his intended great work. Then, at last, Ly ell's, 

 prediction was fulfilled, and, without any apparent warning,, 

 my letter, with the enclosed Essay, came upon him, like a 

 thunderbolt from a cloudless sky ! This forced him to what 

 he considered a premature publicity, and his two friends 

 undertook to have our two papers read before this Society. 



How different from this long study and preparation this 

 philosophic caution this determination not to make known 

 his fruitful conception till he could back it up by over- 

 whelming proofs was my own conduct. The idea came to 

 me, as it had come to Darwin, in a sadden flash of insight : 

 it was thought out in a few hours was written down with 

 such a sketch of its various applications and developments as, 



