Volume I Part 26 (1/2)

Geol. Soc.” Volume XVIII., page 348, 1862.) with extreme interest, and I thank you for sending it, though I should certainly have carefully read it, or anything with your name, in the Journal. It seems to me a masterpiece of close reasoning: although, of course, not a judge of such subjects, I cannot feel any doubt that it is conclusive. Will Owen answer you? I expect that from his arrogant view of his own position he will not answer. Your paper is dreadfully severe on him, but perfectly courteous, and polished as the finest dagger. How kind you are towards me: your first sentence (145/2. ”One of the most accurate observers and original thinkers of our time has discoursed with emphatic eloquence on the Imperfection of the Geological Record.”) has pleased me more than perhaps it ought to do, if I had any modesty in my composition. By the way, after reading the first whole paragraph, I re-read it, not for matter, but for style; and then it suddenly occurred to me that a certain man once said to me, when I urged him to publish some of his miscellaneous wealth of knowledge, ”Oh, he could not write,--he hated it,” etc. You false man, never say that to me again. Your incidental remark on the remarkable specialisation of Plagiaulax (145/3. ”If Plagiaulax be regarded through the medium of the view advocated with such power by Darwin, through what a number of intermediate forms must not the genus have pa.s.sed before it attained the specialised condition in which the fossils come before us!”) (which has stuck in my gizzard ever since I read your first paper) as bearing on the number of preceding forms, is quite new to me, and, of course, is in accordance to my notions a most impressive argument. I was also glad to be reminded of teeth of camel and tarsal bones. (145/4. Op. cit. page 353. A reference to Cuvier's instance ”of the secret relation between the upper canine-shaped incisors of the camel and the bones of the tarsus.”) Descent from an intermediate form, Ahem!

Well, all I can say is that I have not been for a long time more interested with a paper than with yours. It gives me a demoniacal chuckle to think of Owen's pleasant countenance when he reads it.

I have not been in London since the end of September; when I do come I will beat up your quarters if I possibly can; but I do not know what has come over me. I am worse than ever in bearing any excitement. Even talking of an evening for less than two hours has twice recently brought on such violent vomiting and trembling that I dread coming up to London.

I hear that you came out strong at Cambridge (145/5. Prof. Owen, in a communication to the British a.s.sociation at Cambridge (1862) ”On a tooth of Mastodon from the Tertiary marls, near Shanghai,” brought forward the case of the Australian Mastodon as a proof of the remarkable geographical distribution of the Proboscidia. In a subsequent discussion he frankly abandoned it, in consequence of the doubts then urged regarding its authenticity. (See footnote, page 101, in Falconer's paper ”On the American Fossil Elephant,” ”Nat. Hist. Review,” 1863.)), and am heartily glad you attacked the Australian Mastodon. I never did or could believe in him. I wish you would read my little Primula paper in the ”Linnean Journal,” Volume VI. Botany (No. 22), page 77 (I have no copy which I can spare), as I think there is a good chance that you may have observed similar cases. This is my real hobby-horse at present. I have re-tested this summer the functional difference of the two forms in Primula, and find all strictly accurate. If you should know of any cases a.n.a.logous, pray inform me. Farewell, my good and kind friend.

LETTER 146. TO J.D. HOOKER.

(146/1. The following letter is interesting in connection with a letter addressed to Sir J.D. Hooker, March 26th, 1862, No. 136, where the value of Natural Selection is stated more strongly by Sir Joseph than by Darwin. It is unfortunate that Sir Joseph's letter, to which this is a reply, has not been found.)

Down, November 20th [1862].

Your last letter has interested me to an extraordinary degree, and your truly parsonic advice, ”some other wise and discreet person,” etc., etc., amused us not a little. I will put a concrete case to show what I think A. Gray believes about crossing and what I believe. If 1,000 pigeons were bred together in a cage for 10,000 years their number not being allowed to increase by chance killing, then from mutual intercrossing no varieties would arise; but, if each pigeon were a self-fertilising hermaphrodite, a mult.i.tude of varieties would arise. This, I believe, is the common effect of crossing, viz., the obliteration of incipient varieties. I do not deny that when two marked varieties have been produced, their crossing will produce a third or more intermediate varieties. Possibly, or probably, with domestic varieties, with a strong tendency to vary, the act of crossing tends to give rise to new characters; and thus a third or more races, not strictly intermediate, may be produced. But there is heavy evidence against new characters arising from crossing wild forms; only intermediate races are then produced. Now, do you agree thus far? if not, it is no use arguing; we must come to swearing, and I am convinced I can swear harder than you, therefore I am right. Q.E.D.

If the number of 1,000 pigeons were prevented increasing not by chance killing, but by, say, all the shorter-beaked birds being killed, then the WHOLE body would come to have longer beaks. Do you agree?

Thirdly, if 1,000 pigeons were kept in a hot country, and another 1,000 in a cold country, and fed on different food, and confined in different-size aviary, and kept constant in number by chance killing, then I should expect as rather probable that after 10,000 years the two bodies would differ slightly in size, colour, and perhaps other trifling characters; this I should call the direct action of physical conditions.

By this action I wish to imply that the innate vital forces are somehow led to act rather differently in the two cases, just as heat will allow or cause two elements to combine, which otherwise would not have combined. I should be especially obliged if you would tell me what you think on this head.

But the part of your letter which fairly pitched me head over heels with astonishment, is that where you state that every single difference which we see might have occurred without any selection. I do and have always fully agreed; but you have got right round the subject, and viewed it from an entirely opposite and new side, and when you took me there I was astounded. When I say I agree, I must make the proviso, that under your view, as now, each form long remains adapted to certain fixed conditions, and that the conditions of life are in the long run changeable; and second, which is more important, that each individual form is a self-fertilising hermaphrodite, so that each hair-breadth variation is not lost by intercrossing. Your manner of putting the case would be even more striking than it is if the mind could grapple with such numbers--it is grappling with eternity--think of each of a thousand seeds bringing forth its plant, and then each a thousand. A globe stretching to the furthest fixed star would very soon be covered. I cannot even grapple with the idea, even with races of dogs, cattle, pigeons, or fowls; and here all admit and see the accurate strictness of your ill.u.s.tration.

Such men as you and Lyell thinking that I make too much of a Deus of Natural Selection is a conclusive argument against me. Yet I hardly know how I could have put in, in all parts of my book, stronger sentences.

The t.i.tle, as you once pointed out, might have been better. No one ever objects to agriculturalists using the strongest language about their selection, yet every breeder knows that he does not produce the modification which he selects. My enormous difficulty for years was to understand adaptation, and this made me, I cannot but think, rightly, insist so much on Natural Selection. G.o.d forgive me for writing at such length; but you cannot tell how much your letter has interested me, and how important it is for me with my present book in hand to try and get clear ideas. Do think a bit about what is meant by direct action of physical conditions. I do not mean whether they act; my facts will throw some light on this. I am collecting all cases of bud-variations, in contradistinction to seed-variations (do you like this term, for what some gardeners call ”sports”?); these eliminate all effects of crossing.

Pray remember how much I value your opinion as the clearest and most original I ever get.

I see plainly that Welwitschia (146/2. Sir Joseph's great paper on Welwitschia mirabilis was published in the ”Linn. Soc. Trans.” 1863.) will be a case of Barnacles.

I have another plant to beg, but I write on separate paper as more convenient for you to keep. I meant to have said before, as an excuse for asking for so much from Kew, that I have now lost TWO seasons, by accursed nurserymen not having right plants, and sending me the wrong instead of saying that they did not possess.

LETTER 147. TO J.D. HOOKER. Down, 24th [November, 1862].

I have just received enclosed for you, and I have thought that you would like to read the latter half of A. Gray's letter to me, as it is political and nearly as mad as ever in our English eyes. You will see how the loss of the power of bullying is in fact the sore loss to the men of the North from disunion.

I return with thanks Bates' letter, which I was glad to see. It was very good of you writing to him, for he is evidently a man who wants encouragement. I have now finished his paper (but have read nothing else in the volume); it seems to me admirable. To my mind the act of segregation of varieties into species was never so plainly brought forward, and there are heaps of capital miscellaneous observations.

I hardly know why I am a little sorry, but my present work is leading me to believe rather more in the direct action of physical conditions. I presume I regret it, because it lessens the glory of Natural Selection, and is so confoundedly doubtful. Perhaps I shall change again when I get all my facts under one point of view, and a pretty hard job this will be. (147/1. This paragraph was published in ”Life and Letters,” II., page 390. It is not clear why a belief in ”direct action” should diminish the glory of Natural Selection, since the changes so produced must, like any other variations, pa.s.s through the ordeal of the survival of the fittest. On the whole question of direct action see Mr. Adam Sedgwick's ”Presidential Address to the Zoological Section of the British a.s.sociation,” 1899.)

LETTER 148. TO H.W. BATES. Down, November 25th [1862?].

I should think it was not necessary to get a written agreement. (148/1.

Mr. Bates' book, ”A Naturalist on the Amazons,” was published in 1863.) I have never had one from Murray. I suppose you have a letter with terms; if not, I should think you had better ask for one to prevent misunderstandings. I think Sir C. Lyell told me he had not any formal agreements. I am heartily glad to hear that your book is progressing.

Could you find me some place, even a footnote (though these are in nine cases out of ten objectionable), where you could state, as fully as your materials permit, all the facts about similar varieties pairing,--at a guess how many you caught, and how many now in your collection? I look at this fact as very important; if not in your book, put it somewhere else, or let me have cases.

I entirely agree with you on the enormous advantage of thoroughly studying one group.

I really have no criticism to make. (148/2. Mr. Bates' paper on mimetic b.u.t.terflies was read before the Linnean Society, November 21st, 1861, and published in the ”Linn. Soc. Trans.” XXIII., 1862, page 495, under the t.i.tle of ”Contributions to an Insect Fauna of the Amazon Valley.”) Style seems to me very good and clear; but I much regret that in the t.i.tle or opening pa.s.sage you did not blow a loud trumpet about what you were going to show. Perhaps the paper would have been better more divided into sections with headings. Perhaps you might have given somewhere rather more of a summary on the progress of segregation of varieties, and not referred your readers to the descriptive part, excepting such readers as wanted minute detail. But these are trifles: I consider your paper as a most admirable production in every way.

Whenever I come to variation under natural conditions (my head for months has been exclusively occupied with domestic varieties), I shall have to study and re-study your paper, and no doubt shall then have to plague you with questions. I am heartily glad to hear that you are well.