More Letters of Charles Darwin Volume Ii Part 29

For the love of G.o.d help me. I believe all my work (about a fortnight) is useless. Look at this accursed diagram (Figure 9) of the b.u.t.terfly-orchis [Habenaria], which I examined after writing to you yesterday, when I thought all my work done. Some of the ducts of the upper sepal (605/4. These would be described by modern morphologists as lower, not upper, sepals, etc. Darwin was aware that he used these terms incorrectly.) and upper petal run to the wrong bundles on the column. I have seen no such case.

This case apparently shows that not the least reliance can be placed on the course of ducts. I am sure of my facts.

There is great adhesion and extreme displacement of parts where the organs spring from the top of the ovarium. Asa Gray says ducts are very early developed, and it seems to me wonderful that they should pursue this course. It may be said that the lateral ducts in the labellum running into the antero-lateral ovarian bundle is no argument that the labellum consists of three organs blended together.

In desperation (and from the curious way the base of upper petals are soldered at basal edges) I fancied the real form of upper sepal, upper petal and lower sepal might be as represented by red lines, and that there had been an incredible amount of splitting of sepals and petals and subsequent fusion.

This seems a monstrous notion, but I have just looked at Bauer's drawing of allied Bonatea, and there is a degree of lobing of petals and sepals which would account for anything.

Now could you spare me a dry flower out of your Herbarium of Bonatea speciosa (605/5. See "Fertilisation of Orchids," Edition I., page 304 (note), where the resemblances between the anomalous vessels of Bonatea and Habenaria are described. On November 14th, 1861, he wrote to Sir Joseph: "You are a true friend in need. I can hardly bear to let the Bonatea soak long enough."), that I might soak and look for ducts. If I cannot explain the case of Habenaria all my work is smashed. I was a fool ever to touch orchids.

LETTER 606. TO J.D. HOOKER. Down, November 17th [1861].

What two very interesting and useful letters you have sent me. You rather astound me with respect to value of grounds of generalisation in the morphology of plants. It reminds me that years ago I sent you a gra.s.s to name, and your answer was, "It is certainly Festuca (so-and-so), but it agrees as badly with the description as most plants do." I have often laughed over this answer of a great botanist...Lindley, from whom I asked for an orchid with a simple labellum, has most kindly sent me a lot of what he marks "rare" and "rarissima" of peloric orchids, etc., but as they are dried I know not whether they will be of use. He has been most kind, and has suggested my writing to Lady D. Nevill, who has responded in a wonderfully kind manner, and has sent a lot of treasures. But I must stop; otherwise, by Jove, I shall be transformed into a botanist. I wish I had been one; this morphology is surprisingly interesting. Looking to your note, I may add that certainly the fifteen alternating bundles of spiral vessels (mingled with odd beadlike vessels in some cases) are present in many orchids. The inner whorl of anther ducts are oftenest aborted. I must keep clear of Apostasia, though I have cast many a longing look at it in Bauer. (606/1. Apostasia has two fertile anthers like Cypripedium. It is placed by Engler and Prantl in the Apostasieae or Apostasiinae, among the Orchideae, by others in a distinct but closely allied group.)

I hope I may be well enough to read my own paper on Thursday, but I have been very seedy lately. (606/2. "On the two Forms, or Dimorphic Condition, in the Species of the Genus Primula," "Linn. Soc. Journ."

1862. He did read the paper, but it cost him the next day in bed. "Life and Letters," III., page 299.) I see there is a paper at the Royal on the same night, which will more concern you, on fossil plants of Bovey (606/3. Oswald Heer, "The Fossil Flora of Bovey Tracey," "Phil. Trans.

R. Soc." 1862, page 1039.), so that I suppose I shall not have you; but you must read my paper when published, as I shall very much like to hear what you think. It seems to me a large field for experiment. I shall make use of my Orchid little volume in ill.u.s.trating modification of species doctrine, but I keep very, very doubtful whether I am not doing a foolish action in publis.h.i.+ng. How I wish you would keep to your old intention and write a book on plants. (606/4. Possibly a book similar to that described in Letter 696.)

LETTER 607. TO G. BENTHAM. Down, November 26th [1861].

Our notes have crossed on the road. I know it is an honour to have a paper in the "Transactions," and I am much obliged to you for proposing it, but I should greatly prefer to publish in the "Journal." Nor does this apply exclusively to myself, for in old days at the Geological Society I always protested against an abstract appearing when the paper itself might appear. I abominate also the waste of time (and it would take me a day) in making an abstract. If the referee on my paper should recommend it to appear in the "Transactions," will you be so kind as to lay my earnest request before the Council that it may be permitted to appear in the "Journal?"

You must be very busy with your change of residence; but when you are settled and have some leisure, perhaps you will be so kind as to give me some cases of dimorphism, like that of Primula. Should you object to my adding them to those given me by A. Gray? By the way, I heard from A.

Gray this morning, and he gives me two very curious cases in Boragineae.

LETTER 608. TO JOHN LINDLEY.

(608/1. In the following fragment occurs the earliest mention of Darwin's work on the three s.e.xual forms of Catasetum tridentatum. Sir R. Schomburgk (608/2. "Trans. Linn. Soc." XVII., page 522.) described Catasetum tridentatum, Monacanthus viridis and Myanthus barbatus occurring on a single plant, but it remained for Darwin to make out that they are the male, female and hermaphrodite forms of a single species.

(608/3. "Fertilisation of Orchids," Edition I., page 236; Edition II., page 196.)

With regard to the species of Acropera (Gongora) (608/4. Acropera Loddigesii = Gongora galeata: A. luteola = G. fusca ("Index Kewensis").) he was wrong in his surmise. The apparent sterility seems to be explicable by Hildebrand's discovery (608/5. "Bot. Zeitung," 1863 and 1865.) that in some orchids the ovules are not developed until pollinisation has occurred. (608/6. "Fertilisation of Orchids," Edition II., page 172. See Letter 633.))

Down, December 15th [1861].

I am so nearly ready for press that I will not ask for anything more; unless, indeed, you stumbled on Mormodes in flower. As I am writing I will just mention that I am convinced from the rudimentary state of the ovules, and from the state of the stigma, that the whole plant of Acropera luteola (and I believe A. Loddigesii) is male. Have you ever seen any form from the same countries which could be the females? Of course no answer is expected unless you have ever observed anything to bear on this. I may add [judging from the] state of the ovules and of the pollen [that]:--

Catasetum tridentatum is male (and never seeds, according to Schomburgk, whom you have accidentally misquoted in the "Vegetable Kingdom").

Monacanthus viridis is female. Myanthus barbatus is the hermaphrodite form of same species.

LETTER 609. TO J.D. HOOKER. Down, December 18th [1861].

Thanks for your note. I have not written for a long time, for I always fancy, busy as you are, that my letters must be a bore; though I like writing, and always enjoy your notes. I can sympathise with you about fear of scarlet fever: to the day of my death I shall never forget all the sickening fear about the other children, after our poor little baby died of it. The "Genera Plantarum" must be a tremendous work, and no doubt very valuable (such a book, odd as it may appear, would be very useful even to me), but I cannot help being rather sorry at the length of time it must take, because I cannot enter on and understand your work. Will you not be puzzled when you come to the orchids? It seems to me orchids alone would be work for a man's lifetime; I cannot somehow feel satisfied with Lindley's cla.s.sification; the Malaxeae and Epidendreae seem to me very artificially separated. (609/1. Pfitzer (in the "Pflanzenfamilien") places Epidendrum in the Laeliinae-Cattleyeae, Malaxis in the Liparidinae. He states that Bentham united the Malaxideae and Epidendreae.) Not that I have seen enough to form an opinion worth anything.

Your African plant seems to be a vegetable Ornithorhynchus, and indeed much more than that. (609/2. See Sir J.D. Hooker, "On Welwitschia, a new genus of Gnetaceae." "Linn. Soc. Trans." XXIV., 1862-3.) The more I read about plants the more I get to feel that all phanerogams seem comparable with one cla.s.s, as lepidoptera, rather than with one kingdom, as the whole insecta. (609/3. He wrote to Hooker (December 28th, 1861): "I wrote carelessly about the value of phanerogams; what I was thinking of was that the sub-groups seemed to blend so much more one into another than with most cla.s.ses of animals. I suspect crustacea would show more difference in the extreme forms than phanerogams, but, as you say, it is wild speculation. Yet it is very strange what difficulty botanists seem to find in grouping the families together into ma.s.ses.")

Thanks for your comforting sentence about the accursed ducts (accursed though they be, I should like nothing better than to work at them in the allied orders, if I had time). I shall be ready for press in three or four weeks, and have got all my woodcuts drawn. I fear much that publis.h.i.+ng separately will prove a foolish job, but I do not care much, and the work has greatly amused me. The Catasetum has not flowered yet!

In writing to Lindley about an orchid which he sent me, I told him a little about Acropera, and in answer he suggests that Gongora may be its female. He seems dreadfully busy, and I feel that I have more right to kill you than to kill him; so can you send me one or at most two dried flowers of Gongora? if you know the habitat of Acropera luteola, a Gongora from the same country would be the best, but any true Gongora would do; if its pollen should prove as rudimentary as that of Monacanthus relatively to Catasetum, I think I could easily perceive it even in dried specimens when well soaked.

I have picked a little out of Lecoq, but it is awful tedious hunting.

Bates is getting on with his natural history travels in one volume.

(609/4. H.W. Bates, the "Naturalist on the Amazons," 1863. See Volume I., Letters 123, 148, also "Life and Letters," Volume II., page 381.) I have read the first chapter in MS., and I think it will be an excellent book and very well written; he argues, in a good and new way to me, that tropical climate has very little direct relation to the gorgeous colouring of insects (though of course he admits the tropics have a far greater number of beautiful insects) by taking all the few genera common to Britain and Amazonia, and he finds that the species proper to the latter are not at all more beautiful. I wonder how this is in species of the same restricted genera of plants.

If you can remember it, thank Bentham for getting my Primula paper printed so quickly. I do enjoy getting a subject off one's hands completely.

I have now got dimorphism in structure in eight natural orders just like Primula. Asa Gray sent me dried flowers of a capital case in Amsinkia spectabilis, one of the Boragineae. I suppose you do not chance to have the plant alive at Kew.

LETTER 610. TO A.G. MORE. Down, June 7th, 1862.

If you are well and have leisure, will you kindly give me one bit of information: Does Ophrys arachnites occur in the Isle of Wight? or do the intermediate forms, which are said to connect abroad this species and the bee-orchis, ever there occur?

Some facts have led me to suspect that it might just be possible, though improbable in the highest degree, that the bee [orchis] might be the self-fertilising form of O. arachnites, which requires insects' aid, something [in the same way] as we have self-fertilising flowers of the violet and others requiring insects. I know the case is widely different, as the bee is borne on a separate plant and is incomparably commoner. This would remove the great anomaly of the bee being a perpetual self-fertiliser. Certain Malpighiaceae for years produce only one of the two forms. What has set my head going on this is receiving to-day a bee having one alone of the best marked characters of O.

arachnites. (610/1. Ophrys arachnites is probably more nearly allied to O. aranifera than to O. apifera. For a case somewhat a.n.a.logous to that suggested see the description of O. scolopax in "Fertilisation of Orchids," Edition II., page 52.) Pray forgive me troubling you.

LETTER 611. TO G. BENTHAM. Down, June 22nd [1862?].

Here is a piece of presumption! I must think that you are mistaken in ranking Hab[enaria] chlorantha (611/1. In Hooker's "Students' Flora,"

1884, page 395, H. chlorantha is given as a subspecies of H. bifolia.

Sir J.D. Hooker adds that they are "according to Darwin, distinct, and require different species of moths to fertilise them. They vary in the position and distances of their anther-cells, but intermediates occur."

See "Fertilisation of Orchids," Edition II., page 73.) as a variety of H. bifolia; the pollen-ma.s.ses and stigma differ more than in most of the best species of Orchis. When I first examined them I remember telling Hooker that moths would, I felt sure, fertilise them in a different manner; and I have just had proof of this in a moth sent me with the pollinia (which can be easily recognised) of H. chlorantha attached to its proboscis, instead of to the sides of its face, as an H. bifolia.

Forgive me scribbling this way; but when a man gets on his hobby-horse he always is run away with. Anyhow, nothing here requires any answer.

LETTER 612. TO J.D. HOOKER. Down, [September] 14th [1862].

Your letter is a mine of wealth, but first I must scold you: I cannot abide to hear you abuse yourself, even in joke, and call yourself a stupid dog. You, in fact, thus abuse me, because for long years I have looked up to you as the man whose opinion I have valued more on any scientific subject than any one else in the world. I continually marvel at what you know, and at what you do. I have been looking at the "Genera" (612/1. "Genera Plantarum," by Bentham and Hooker, Volume I., Part I., 1862.), and of course cannot judge at all of its real value, but I can judge of the amount of condensed facts under each family and genus.

I am glad you know my feeling of not being able to judge about one's own work; but I suspect that you have been overworking. I should think you could not give too much time to Wellwitchia (I spell it different every time I write it) (612/2. "On Welwitschia," "Linn. Soc. Trans." [1862], XXIV., 1863.); at least I am sure in the animal kingdom monographs cannot be too long on the osculant groups.

Hereafter I shall be excessively glad to read a paper about Aldrovanda (612/3. See "Insectivorous Plants," page 321.), and am very much obliged for reference. It is pretty to see how the caught flies support Drosera; nothing else can live.

Thanks about plants with two kinds of anthers. I presume (if an included flower was a Ca.s.sia) (612/4. Todd has described a species of Ca.s.sia with an arrangement of stamens like the Melastomads. See Chapter 2.X.II.) that Ca.s.sia is like lupines, but with some stamens still more rudimentary. If I hear I will return the three Melastomads; I do not want them, and, indeed, have cuttings. I am very low about them, and have wasted enormous labour over them, and cannot yet get a glimpse of the meaning of the parts. I wish I knew any botanical collector to whom I could apply for seeds in their native land of any Heterocentron or Monochoetum; I have raised plenty of seedlings from your plants, but I find in other cases that from a h.o.m.omorphic union one generally gets solely the parent form. Do you chance to know of any botanical collector in Mexico or Peru? I must not now indulge myself with looking after vessels and h.o.m.ologies. Some future time I will indulge myself. By the way, some time I want to talk over the alternation of organs in flowers with you, for I think I must have quite misunderstood you that it was not explicable.

I found out the Verbasc.u.m case by pure accident, having transplanted one for experiment, and finding it to my astonishment utterly sterile.

I formerly thought with you about rarity of natural hybrids, but I am beginning to change: viz., oxlips (not quite proven), Verbasc.u.m, Cistus (not quite proven), Aegilops triticoides (beautifully shown by G.o.dron), Weddell's and your orchids (612/5. For Verbasc.u.m see "Animals and Plants," Edition II., Volume I., page 356; for Cistus, Ibid., Edition II., Volume I., page 356, Volume II., page 122; for Aegilops, Ibid., Edition II., Volume I., page 330, note.), and I daresay many others recorded. Your letters are one of my greatest pleasures in life, but I earnestly beg you never to write unless you feel somewhat inclined, for I know how hard you work, as I work only in the morning it is different with me, and is only a pleasant relaxation. You will never know how much I owe to you for your constant kindness and encouragement.

LETTER 613. TO JOHN LUBBOCK (Lord Avebury). Cliff Cottage, Bournemouth, Hants, September 2nd [1862].