292 The Study of Animal Life part iv 



"Such change of needs involves the necessity of changed 

 action in order to satisfy these needs, and, in consequence, of new 

 habits." 



' ' It follows that such and such parts, formerly less used, are 

 now more frequently employed, and in consequence become more 

 highly developed ; new parts also become insensibly evolved in the 

 creature by its own efforts from within." 



"These gains or losses of organic development, due to use or 

 disuse, are transmitted to offspring, provided they have been com- 

 mon to both sexes, or to the animals from which the offspring have 

 descended." 



The historian of the evolution of evolution theories 

 should take account of many workers besides Buffon, 

 Erasmus Darwin, and Lamarck; of Treviranus (1776- 

 1837), whose Biology or Philosophy of Living Nature (1 802- 

 1805) is full of evolutionary suggestions; of Geoffroy St. 

 Hilaire, who in 1830, before the French Academy of 

 Science, fought with Cuvier, the fellow-worker of his youth, 

 ah intellectual duel on the question of descent ; of Goethe 

 who, in his eighty-first year, heard the tidings of Geoffroy's 

 defeat with an interest which transcended the political 

 anxieties of the time, and whose own epic of evolution sur- 

 passes that of Lucretius ; of Oken's speculative mist, amid 

 which the light of evolutionary ideas danced like a will-o'- 

 the-wisp ; of many others in whose mind the truth grew if 

 it did not blossom. But we must now recognise the work 

 of Charles Darwin. 



6. Darwin. — Though the general tenor of Darwin's life 

 — the impression of an industrious open-minded observer 

 and thinker, the picture of a man full of mercy, kindliness, 

 and peace — was familiar to many, his biography has filled 

 in those little details which make our impression living. 

 We see him now, as in a Holbein picture, with all the 

 paraphernalia of daily pursuit round about him. His high 

 chair, his orderly shelves, his torn-up reference books, his 

 window-sill laboratory, his yellow-back novels, his snuff- 

 box, and a hundred little touches, make the picture alive. 

 We learn, too, his methods of laborious but never toilsome 

 work, and the gradual progress of his thought from the con- 

 ventionalism of youth to the convictions of matured man- 



