of your opinion in a matter with which you are not so fully acquainted as myself should lay me under any obligation to be led by it, after mature consideration seemed to show that the best course for me to follow was the one which I took. Hoping soon to see you, I remain, very sincerely yours, P.S.-I forgot to say that I acted upon your suggestion about the Linnean, and have been proposed by Darwin, Hooker, and Huxley. From C. Darwin to G. J. Romanes. Down, Beckenham, Kent: July 12, 1875. ( I am correcting a second edition of Var. under Dom.,' and find that I must do it pretty fully. Therefore I give a short abstract of potato graft hybrids, and I want to know whether I did not send you a reference about beet. Did you look to this, and can you tell me anything about it? I hope with all my heart that you are getting on pretty well with your experiments; I have been led to think a good deal on the subject, and am convinced of its high importance, though it will take years of hammering before physiologists will admit that the sexual organs only collect the generative elements. The edition will be published in November, and then you will see all that I have collected, but I believe that you saw all the more important cases. The case of vine in Gardeners' Chronicle' which I sent you I think may only be a bud-variation, not due to grafting. I have heard indirectly of your splendid success with nerves of Medusa. We have been at Abinger Hall for a month for rest which I much required, and I saw there the cut-leaved vine, which seems splendid for graft hybridisation. Yours very sincerely, To C. Darwin, Esq. CH. DARWIN. Dunskaith: July 14, 1875. I was very glad to receive your letter, having been previously undecided whether to write and let you know how I am getting on, or to wait until I got a veritable hybrid. In one of your letters you advised me to look up the 'beet' case, but I could nowhere find any references to it. Dr. Hooker told me that although he could not then remember the man's name, he remembered that the experimenter did not save the seed, but dug up his roots for exhibition. I forget whether it was Dr. Masters, Bentham, or Mr. Dyer who told me that the experiment had been performed in Ireland, although they could not remember by whom. But if the experimenter did not save the seed, the mere fact of his sticking two roots together would have no bearing on Pangenesis, and so I did not take any trouble to find out who the experimenter was. As you have heard about the Medusæ, I fear you will infer that they must have diverted my attention from Pangenesis; but although it is true that they have consumed a great deal of time and energy, I have done my best to keep Pangenesis in the foreground. The proximate success of my grafting is all that I can desire, although, of course, it is as yet too early in the year to know what the ultimate success will be. I mean that, although I cannot yet tell whether the tissue of one variety is affecting that of the other, I have obtained intimate adhesion in the great majority of experiments. Potatoes, however, are an exception, for at first I began with a method which I thought very cunning, and which I still think would have been successful but for one little oversight. The method was to punch out the eyes with an electroplated cork-borer, and replace them in a flat-bottomed hole of a slightly smaller size made with another instrument in the other tuber. The fit, of course, was always perfect; but what I went wrong in was not having the cork-borers made of the best steel; for after I got about one hundred potatoes planted out, I found that the inserted plugs did not adhere. I therefore tried some sections with an exceedingly sharp knife that surgeons use for amputating, and the surfaces cut with this always adhered under pressure. The knife, however, must be set up in a guide, in order to get the surfaces perfectly flat. Next year I shall get cork-borers made of the same steel as this knife is made of, and then hope to turn out graft-hybrids by the score. Even this year, however, a great many of my potatoes are coming up, so I hope that some of the eyes may have struck. I think it is desirable to get some easy way of experimenting with potatoes (such as the cork-boring plan), and one independent of delicacy in manipulation, for then everybody could verify the results for himself, and not, as now, look with suspicion upon the success of other people. With beans I get very good adhesion of the young shoots, but the parts which grow after the operation always continue separate. In some cases I am trying a succession of operations as the plant grows. With beetroots and mangold-wurzel of all varieties, adhesion is certain to occur with my method of getting up great pressure by allowing the plants to grow for a few days inside the binding. I have therefore made grafts of all ages, beginning with roots only an inch or two long and as thin as threads. The other vegetables also are doing well, but with flowers I have had no success. The vine-cuttings were too young to do anything with this year, but I hear from my cousin, who has charge of them, that they are doing well. They certainly have very extraordinary leaves. This year I never expected to be more than one in which to gain experience, for embryo grafting, as it has never been tried by anybody, cannot be learned about except by experiments. But as I am a young man yet, and hope to do a good deal of 'hammering,' I shall not let Pangenesis alone until I feel quite sure that it does not admit of being any further driven home by experimental work; and even if I never get positive results, I shall always continue to believe in the theory. I am very sorry to hear that you much needed rest,' and do earnestly hope that you will not work too hard over the new edition of one of the most laborious treatises in our language-a treatise to which we always refer for every kind of information that we cannot find anywhere else. Dunskaith: November 7. I have to-day sent you a beautifully successful graft. It is of a red and white carrot, each bisected longitudinally, and two of the opposite halves joined. You will see that the union is very intimate, and that the originally red half has become wholly white. The graft was made about three months ago, at which time the carrots were very small, but the colours very decided. I think, therefore, that unless red carrots ever turn into white ones-which, I suppose, is absurd -the specimen I send is a graft-hybrid so far as the parts in contact are concerned. It will be of great importance, as you observed in your last letter, in a case like this, to see if the other parts are affected— i.e. to get the plant to seed if possible. This, I suppose, can only be done at this late season with so young a plant by putting it in a greenhouse. Perhaps, therefore, you might pot it, as soon as it arrives, and keep it till I go up. If you do not care to take charge of it altogether, I can then get a home for it somewhere in the South. It will not require a deep pot, for I see that I have cut through the end of one of the roots. It would be as well, before potting, to cut off the end of the other root also, so that the one half may not grow longer than the other, and thus perhaps assert an undue amount of influence during the subsequent history of the hybrid. If the plant |