44 CHARLES DARWIN. 



Never." We know that a few months later he would 

 have himself accepted the view he imputes to Lyell, and 

 would have regarded the extinction as due to some cir- 

 cumstance affecting the competition for food or some 

 other relationship with the organic life of the same 

 district. It is probable that the above quotation from 

 his Diary was written in connection with the conclusion 

 of Chapter IX. of the first edition of the " Journal of 

 the Voyage" (pp. 211, 212); for the latter is a fuller 

 exposition of the same argument.* 



" One is tempted to believe," he says, " in such simple rela- 

 tions, as variation of climate and food, or introduction of 

 enemies, or the increased numbers of other species, as the cause 

 of the succession of races. But it may be asked whether it is 

 probable that [" than" is an evident misprint in the original] any 

 such cause should have been in action during the same epoch 

 over the whole northern hemisphere, so as to destroy the 

 Elephas primigenius on the shores of Spain, on the plains of 

 Siberia, and in Northern America. . . . These cases of 

 extinction forcibly recall the idea (I do not wish to draw any 

 close analogy) of certain fruit-trees, which, it has been asserted, 

 though grafted on young stems, planted in varied situations, 

 and fertilized by the richest manures, yet at one period have 

 all withered away and perished. A fixed and determined length 

 of life has in such cases been given to thousands and thousands 

 of buds (or individual germs), although produced in long 

 succession." 



He then concludes that the animals of one species, 

 although " each individual appears nearly independent 

 of its kind," may be bound together by common laws. 



* " We are told in the " Life and Letters " that the last proof of 

 the "Journal" was finished in 1837. The Diary, as stated above, 

 was written between July, 1837, and February, 1838. 



