264 'VARIATION UNDER DOMESTICATION.' [1868. 



vanity), " I can hardly tell you how much I admire the 

 chapter on 'Pangenesis.' It is 2, positive comfort to me to 

 have any feasible explanation of a difficulty that has always 

 been haunting me, and I shall never be able to give it up till 

 a better one supplies its place, and that I think hardly possi- 

 ble, &c." Now his foregoing [italicised] words express my 

 sentiments exactly and fully : though perhaps I feel the 

 relief extra strongly from having during many years vainly 

 attempted to form some hypothesis. When you or Huxley 

 I say that a single cell of a plant, or the stump of an amputa- 

 ted limb, have the ''potentiality" of reproducing the whole 

 — or " diffuse an influence," these words give me no positive 

 idea ; — but when it is said that the cells of a plant, or stump, 

 include atoms derived from every other cell of the whole 

 organism and capable of development, I gain a distinct idea. 

 But this idea would not be worth a rush, if it applied to one 

 case alone ; but it seems to me to apply to all the forms of 

 reproduction — inheritance — metamorphosis — to the abnormal 

 transposition of organs — to the direct action of the male ele- 

 ment on the mother plant, &:c. Therefore I fully believe 

 that each cell does actually throw off an atom or gemmule of 

 its contents ; — but whether or not, this hypothesis serves as 

 a useful connecting link for various grand classes of physio- 

 logical facts, which at present stand absolutely isolated. 



I have touched on the doubtful point (alluded to by 

 Huxley) how far atoms derived from the same cell may 

 become developed into different structure accordingly as they 

 are differently nourished ; I advanced as illustrations galls 

 and polypoid excrescences. . . . 



It is a real pleasure to me to write to you on this subject, 

 and I should be delighted if we can understand each other ; 

 but you must not let your good nature lead you on. Re- 

 member, we always fight tooth and nail. We go to London 

 on Tuesday, first for a week to Queen Anne Street, and after- 

 wards to Miss Wedgwood's, in Regent's Park, and stay the 

 whole month, which, as my gardener truly says, is a "terrible 

 thing " for my experiments. 



