Volume Ii Part 37 (1/2)

(The above is a free translation of Muller's words.)) I am convinced that if you can prove that a plant growing in a distant place under different conditions is more effective in fertilisation than one growing close by, you will make a great step in the essence of s.e.xual reproduction.

Prof. Asa Gray and Dr. Hooker have been staying here, and, oddly enough, they knew nothing of your paper on Martha (678/3. F. Muller has described (”Bot. Zeitung,” 1866, page 129) the explosive mechanism by which the pollen is distributed in Martha (Posoqueria) fragrans. He also gives an account of the remarkable arrangement for ensuring cross-fertilisation. See ”Forms of Flowers,” Edition II., page 131.), though the former was aware of the curious movements of the stamens, but so little understood the structure of the plant that he thought it was probably a dimorphic species. Accordingly, I showed them your drawings and gave them a little lecture, and they were perfectly charmed with your account. Hildebrand (678/4. See Letter 206, Volume I.) has repeated his experiments on potatoes, and so have I, but this summer with no result.

LETTER 679. TO F. MULLER. Down, March 14th [1869].

I received some time ago a very interesting letter from you with many facts about Oxalis, and about the non-seeding and spreading of one species. I may mention that our common O. acetosella varies much in length of pistils and stamens, so that I at first thought it was certainly dimorphic, but proved it by experiment not to be so. Boiseria (679/1. This perhaps refers to Boissiera (Ladizabala).) has after all seeded well with me when crossed by opposite form, but very sparingly when self-fertilised. Your case of Faramea astonishes me. (679/2. See ”Forms of Flowers,” Edition II., page 129. Faramea is placed among the dimorphic species.) Are you sure there is no mistake? The difference in size of flower and wonderful difference in size and structure of pollen-grains naturally make me rather sceptical. I never fail to admire and to be surprised at the number of points to which you attend. I go on slowly at my next book, and though I never am idle, I make but slow progress; for I am often interrupted by being unwell, and my subject of s.e.xual selection has grown into a very large one. I have also had to correct a new edition of my ”Origin,” (679/3. The 5th edition.), and this has taken me six weeks, for science progresses at railroad speed.

I cannot tell you how rejoiced I am that your book is at last out; for whether it sells largely or not, I am certain it will produce a great effect on all capable judges, though these are few in number.

P.S.--I have just received your letter of January 12th. I am greatly interested by what you say on Eschscholtzia; I wish your plants had succeeded better. It seems pretty clear that the species is much more self-sterile under the climate of Brazil than here, and this seems to me an important result. (679/4. See Letter 677.) I have no spare seeds at present, but will send for some from the nurseryman, which, though not so good for our purpose, will be worth trying. I can send some of my own in the autumn. You could simply cover up separately two or three single plants, and see if they will seed without aid,--mine did abundantly.

Very many thanks for seeds of Oxalis: how I wish I had more strength and time to carry on these experiments, but when I write in the morning, I have hardly heart to do anything in the afternoon. Your gra.s.s is most wonderful. You ought to send account to the ”Bot. Zeitung.” Could you not ascertain whether the barbs are sensitive, and how soon they become spiral in the bud? Your bird is, I have no doubt, the Molothrus mentioned in my ”Journal of Travels,” page 52, as representing a North American species, both with cuckoo-like habits. I know that seeds from same spike transmitted to a certain extent their proper qualities; but as far as I know, no one has. .h.i.therto shown how far this holds good, and the fact is very interesting. The experiment would be well worth trying with flowers bearing different numbers of petals. Your explanation agrees beautifully with the hypothesis of pangenesis, and delights me.

If you try other cases, do draw up a paper on the subject of inheritance of separate flowers for the ”Bot. Zeitung” or some journal. Most men, as far as my experience goes, are too ready to publish, but you seem to enjoy making most interesting observations and discoveries, and are sadly too slow in publis.h.i.+ng.

LETTER 680. TO F. MULLER. Barmouth, July 18th, 1869.

I received your last letter shortly before leaving home for this place.

Owing to this cause and to having been more unwell than usual I have been very dilatory in writing to you. When I last heard, about six or eight weeks ago, from Mr. Murray, one hundred copies of your book had been sold, and I daresay five hundred may now be sold. (680/1. ”Facts and Arguments for Darwin,” 1869: see Volume I., Letter 227.) This will quite repay me, if not all the money; for I am sure that your book will have got into the hands of a good many men capable of understanding it: indeed, I know that it has. But it is too deep for the general public.

I sent you two or three reviews--one of which, in the ”Athenaeum,” was unfavourable; but this journal has abused me, and all who think with me, for many years. (680/2. ”Athenaeum,” 1869, page 431.) I enclose two more notices, not that they are worth sending: some other brief notices have appeared. The case of the Abitulon sterile with some individuals is remarkable (680/3. ”Bestaubungsversuche an Abutilon-Arten.” ”Jenaische Zeitschr.” VII., 1873, page 22.): I believe that I had one plant of Reseda odorata which was fertile with own pollen, but all that I have tried since were sterile except with pollen from some other individual.

I planted the seeds of the Abitulon, but I fear that they were crushed in the letter. Your Eschscholtzia plants were growing well when I left home, to which place we shall return by the end of this month, and I will observe whether they are self-sterile. I sent your curious account of the monstrous Begonia to the Linnean Society, and I suppose it will be published in the ”Journal.” (680/4. ”On the Modification of the Stamens in a Species of Begonia.” ”Journ. Linn. Soc.” XI., 1871, page 472.) I sent the extract about grafted orange trees to the ”Gardeners'

Chronicle,” where it appeared. I have lately drawn up some notes for a French translation of my Orchis book: I took out your letters to make an abstract of your numerous discussions, but I found I had not strength or time to do so, and this caused me great regret. I have [in the French edition] alluded to your work, which will also be published in English, as you will see in my paper, and which I will send you. (680/5. ”Notes on the Fertilisation of Orchids.” ”Ann. Mag. Nat. Hist.” 1869, Volume IV., page 141. The paper gives an English version of the notes prepared for the French edition of the Orchid book.)

P.S.--By an odd chance, since I wrote the beginning of this letter, I have received one from Dr. Hooker, who has been reading ”Fur Darwin”: he finds that he has not knowledge enough for the first part; but says that Chapters X. and XI. ”strike me as remarkably good.” He is also particularly struck with one of your highly suggestive remarks in the note to page 119. a.s.suredly all who read your book will greatly profit by it, and I rejoice that it has appeared in English.

LETTER 681. TO F. MULLER. Down, December 1st [1869].

I am much obliged for your letter of October 18th, with the curious account of Abutilon, and for the seeds. A friend of mine, Mr. Farrer, has lately been studying the fertilisation of Pa.s.siflora (681/1. See Letters 701 and 704.), and concluded from the curiously crooked pa.s.sage into the nectary that it could not be fertilised by humming-birds; but that Tacsonia was thus fertilised. Therefore I sent him the pa.s.sage from your letter, and I enclose a copy of his answer. If you are inclined to gratify him by making a few observations on this subject I shall be much obliged, and will send them on to him. I enclose a copy of my rough notes on your Eschscholtzia, as you might like to see them. Somebody has sent me from Germany two papers by you, one with a most curious account of Alisma (681/2. See Letter 672.), and the other on crustaceans. Your observations on the branchiae and heart have interested me extremely.

Alex. Aga.s.siz has just paid me a visit with his wife. He has been in England two or three months, and is now going to tour over the Continent to see all the zoologists. We liked him very much. He is a great admirer of yours, and he tells me that your correspondence and book first made him believe in evolution. This must have been a great blow to his father, who, as he tells me, is very well, and so vigorous that he can work twice as long as he (the son) can.

Dr. Meyer has sent me his translation of Wallace's ”Malay Archipelago,”

which is a valuable work; and as I have no use for the translation, I will this day forward it to you by post, but, to save postage, via England.

LETTER 682. TO F. MULLER. Down, May 12th [1870].

I thank you for your two letters of December 15th and March 29th, both abounding with curious facts. I have been particularly glad to hear in your last about the Eschscholtzia (682/1. See Letter 677.); for I am now rearing crossed and self-fertilised plants, in antagonism to each other, from your semi-sterile plants so that I may compare this comparative growth with that of the offspring of English fertile plants. I have forwarded your postscript about Pa.s.siflora, with the seeds, to Mr.

Farrer, who I am sure will be greatly obliged to you; the turning up of the pendant flower plainly indicates some adaptation. When I next go to London I will take up the specimens of b.u.t.terflies, and show them to Mr. Butler, of the British Museum, who is a learned lepidopterist and interested on the subject. This reminds me to ask you whether you received my letter [asking] about the ticking b.u.t.terfly, described at page 33 of my ”Journal of Researches”; viz., whether the sound is in anyway s.e.xual? Perhaps the species does not inhabit your island. (682/2.

Papilio feronia, a Brazilian species capable of making ”a clicking noise, similar to that produced by a toothed wheel pa.s.sing under a spring catch.”--”Journal,” 1879, page 34.)

The case described in your last letter of the trimorphic monocotyledon Pontederia is grand. (682/3. This case interested Darwin as the only instance of heterostylism in Monocotyledons. See ”Forms of Flowers,”

Edition II., page 183. F. Muller's paper is in the ”Jenaische Zeitschrift,” 1871.) I wonder whether I shall ever have time to recur to this subject; I hope I may, for I have a good deal of unpublished material.

Thank you for telling me about the first-formed flower having additional petals, stamens, carpels, etc., for it is a possible means of transition of form; it seems also connected with the fact on which I have insisted of peloric flowers being so often terminal. As pelorism is strongly inherited (and [I] have just got a curious case of this in a leguminous plant from India), would it not be worth while to fertilise some of your early flowers having additional organs with pollen from a similar flower, and see whether you could not make a race thus characterised?

(682/4. See Letters 588, 589. Also ”Variation under Domestication,”