ix] OF EVOLUTION 103 



In caves in that country, a number of bones were 

 found which, though evidently belonging to ' extinct ' 

 animals, yet must have belonged to forms resembling 

 the kangaroos and other ' pouched animals ' (mar- 

 supials) now so distinctive of that continent. But of 

 this fact Darwin was not aware until after his return 

 to England in 1836. 



Among the objects sent from home, which awaited 

 Darwin on his return to Monte Video, was the second 

 volume of LyelTs Principles, then newly published ; 

 this book, while rejecting Lamarckism, was crowded 

 with facts and observations concerning variation, 

 hybridism, the struggle for existence, and many other 

 questions bearing on the great problem of the origin 

 of species. I think there can be no doubt that from 

 this time Darwin came to regard the question of 

 species with an interest he had never felt before. 



It is of course not suggested that, at this early 

 date, Darwin had formed any definite ideas as to the 

 mode in which new species might possibly arise from 

 pre-existing ones or even that he had been converted 

 to a belief in evolution. Indeed in 1877 he wrote 

 1 When I was on board the Beagle I believed in the 

 permanence of species' yet he adds 'but as far as 

 I can remember vague doubts occasionally flitted 

 across my mind.' Such ' vague doubts ' could scarcely 

 have failed to have arisen when, as happened during 

 all his journeys from north to south of the South 



