Introduction 5 



I — and I may add, the public generally — failed also to 

 see what the unaided reader who was new to the subject 

 would be almost certain to overlook, I mean, that, 

 according to Mr. Darwin, the variations whose accumulation 

 resulted in diversity of species and genus were indefinite, 

 fortuitous, attributable but in small degree to any known 

 causes, and without a general principle underlying them 

 which would cause them to appear steadily in a given 

 direction for many successive generations and in a con- 

 siderable number of individuals at the same time. We 

 did not know that the theory of evolution was one that had 

 been quietly but steadily gaining ground during the last 

 hundred years. Buffon we knew by name, but he sounded 

 too like " buffoon " for any good to come from him. We 

 had heard also of Lamarck, and held him to be a kind of 

 French Lord Monboddo ; but we knew nothing of his 

 doctrine save through the caricatures promulgated by 

 his opponents, or the misrepresentations of those who had 

 another kind of interest in disparaging him. Dr. Erasmus 

 Darwin we believed to be a forgotten minor poet, but 

 ninety-nine out of every hundred of us had never so much 

 as heard of the " Zoonomia." We were little likely, there- 

 fore, to know that Lamarck drew very largely from Buffon, 

 and probably also from Dr. Erasmus Darwin, and that 

 this last-named writer, though essentially original, was 

 founded upon Buffon, who was greatly more in advance 

 of any predecessor than any successor has been in advance 

 of him. 



We did not know, then, that according to the earlier 

 writers the variations whose accumulation results in species 

 were not fortuitous and definite, but were due to a known 

 principle of universal application — namely, " sense of 

 need " — or apprehend the difference between a theory of 

 evolution which has a backbone, as it were, in the tolerably 

 constant or slowly varying needs of large numbers of 

 individuals for long periods together, and one which has 

 no such backbone, but according to which the progress 



