310 EVOLUTION [CHAP. IV 



Letter 225 you with this note to thank you for your most kind and 

 extremely honourable notice of my works. 



When I tell you that ever since I was an undergraduate 

 at Cambridge I have felt towards you the most unfeigned 

 respect, from all that I continually heard from poor dear 

 Henslow and others of your great knowledge and original 

 researches, you will believe me when I say that I have rarely 

 in my life been more gratified than by reading your 

 address ; though I feel " ; that you speak much too strongly 

 of what I have done. Your notice of pangenesis l has par- 

 ticularly pleased me, for it has been generally neglected or 

 disliked by my friends ; yet I fully expect that it will some 

 day be more successful. I believe I quite agree with you in 

 the manner in which the cast-off atoms or so-called gemmules 

 probably act : 2 I have never supposed that they were developed 

 into free cells, but that they penetrated other nascent cells 

 and modified their subsequent development. This process 

 I have actually compared with ordinary fertilisation. The 

 cells thus modified, I suppose cast off in their turn modified 

 gemmules, which again combine with other nascent cells, and 

 so on. But I must not trouble you any further. 



Letter 226 To August Weismann. 



Down, Oct. 22nd, 1868. 



I am very much obliged for your kind letter, and I 

 have waited for a week before answering it in hopes of 



1 " It would be unpardonable to finish these somewhat desultory 

 remarks without adverting to one of the most interesting subjects of the 

 day, the Darwinian doctrine of pangenesis. . . . Like everything which 

 comes from the pen of a writer whom I have no hesitation, so far as my 

 judgment goes, in considering as by far the greatest observer of our age, 

 whatever may be thought of his theories when carried out to their 

 extreme results, the subject demands a careful and impartial considera- 

 tion." (Berkeley, p. 86.) 



2 " Assuming the general truth of the theory that molecules endowed 

 with certain attributes are cast off by the component cells of such infini- 

 tesimal minuteness as to be capable of circulating with the fluids, and in 

 the end to be present in the unimpregnated embryo-cell and spermato- 

 zoid ... it seems to me far more probable that they should be capable 

 under favourable circumstances of exercising an influence analogous to 

 that which is exercised by the contents of the pollen-tube or spermato- 

 zoid on the embryo-sac or ovum, than that these particles should be 

 themselves developed into cells " (Berkeley, p. 87). 



