More Letters of Charles Darwin — Volume 2

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 illustrating modification of species doctrine, but I keep very, very doubtful whether I am not doing a foolish action in publishing. 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 sexual 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 classification; 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 class, 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 classes 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 masses.")

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 publishing 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 analogous 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-masses 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 Cassia) (612/4. Todd has described a species of Cassia with an arrangement of stamens like the Melastomads. See Chapter 2.X.II.) that Cassia 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 homomorphic 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 homologies. 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 Verbascum 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), Verbascum, Cistus (not quite proven), Aegilops triticoides (beautifully shown by Godron), Weddell's and your orchids (612/5. For Verbascum 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}.

Hearty thanks for your note. I am so glad that your tour answered so splendidly. My poor patients (613/1. Mrs. Darwin and one of her sons, both recovering from scarlet fever.) got here yesterday, and are doing well, and we have a second house for the well ones. I write now in great haste to beg you to look (though I know how busy you are, but I cannot think of any other naturalist who would be careful) at any field of common red clover (if such a field is near you) and watch the hive-bees: probably (if not too late) you will see some sucking at the mouth of the little flowers and some few sucking at the base of the flowers, at holes bitten through the corollas. All that you will see is that the bees put their heads deep into the {flower} head and rout about. Now, if you see this, do for Heaven's sake catch me some of each and put in spirits and keep them separate. I am almost certain that they belong to two castes, with long and short proboscids. This is so curious a point that it seems worth making out. I cannot hear of a clover field near here.

LETTER 614. TO JOHN LUBBOCK (Lord Avebury). Cliff Cottage, Bournemouth, Wednesday, September 3rd {1862}.

I beg a million pardons. Abuse me to any degree, but forgive me: it is all an illusion (but almost excusable) about the bees. (614/1. H. Muller, "Fertilisation of Flowers," page 186, describes hive-bees visiting Trifolium pratense for the sake of the pollen. Darwin may perhaps have supposed that these were the variety of bees whose proboscis was long enough to reach the nectar. In "Cross and Self Fertilisation," page 361, Darwin describes hive-bees apparently searching for a secretion on the calyx. In the same passage in "Cross and Self Fertilisation" he quotes Muller as stating that hive-bees obtain nectar from red clover by breaking apart the petals. This seems to us a misinterpretation of the "Befruchtung der Blumen," page 224.) I do so hope that you have not wasted any time from my stupid blunder. I hate myself, I hate clover, and I hate bees.

(FIGURE 10. — DIAGRAM OF CRUCIFEROUS FLOWER. FIGURE 11. — DISSECTION OF CRUCIFEROUS FLOWER.

Laid flat open, showing by dotted lines the course of spiral vessels in all the organs; sepals and petals shown on one side alone, with the stamens on one side above with course of vessels indicated, but not prolonged. Near side of pistil with one spiral vessel cut away.)

LETTER 615. TO J.D. HOOKER. Cliff Cottage, Bournemouth, September 11th, 1862.

You once told me that Cruciferous flowers were anomalous in alternation of parts, and had given rise to some theory of dedoublement.

Having nothing on earth to do here, I have dissected all the spiral vessels in a flower, and instead of burning my diagrams {Figures 10 and 11}, I send them to you, you miserable man. But mind, I do not want you to send me a discussion, but just some time to say whether my notions are rubbish, and then burn the diagrams. It seems to me that all parts alternate beautifully by fours, on the hypothesis that two short stamens of outer whorl are aborted (615/1. The view given by Darwin is (according to Eichler) that previously held by Knuth, Wydler, Chatin, and others. Eichler himself believes that the flower is dimerous, the four longer stamens being produced by the doubling or splitting of the upper (i.e. antero-posterior) pair of stamens. If this view is correct, and there are good reasons for it, it throws much suspicion on the evidence afforded by the course of vessels, for there is no trace of the common origin of the longer stamens in the diagram (Figure 11). Again, if Eichler is right, the four vessels shown in the section of the ovary are misleading. Darwin afterwards gave a doubtful explanation of this, and concluded that the ovary is dimerous. See Letter 616.); and this view is perhaps supported by their being so few, only two sub-bundles in the two lateral main bundles, where I imagine two short stamens have aborted, but I suppose there is some valid objection against this notion. The course of the side vessels in the sepals is curious, just like my difficulty in Habenaria. (615/2. See Letter 605.) I am surprised at the four vessels in the ovarium. Can this indicate four confluent pistils? anyhow, they are in the right alternating position. The nectary within the base of the shorter stamens seems to cause the end sepals apparently, but not really, to arise beneath the lateral sepals.

I think you will understand my diagrams in five minutes, so forgive me for bothering you. My writing this to you reminds me of a letter which I received yesterday from Claparede, who helped the French translatress of the "Origin" (615/3. The late Mlle. Royer.), and he tells me he had difficulty in preventing her (who never looked at a bee's cell) from altering my whole description, because she affirmed that an hexagonal prism must have an hexagonal base! Almost everywhere in the "Origin," when I express great doubt, she appends a note explaining the difficulty, or saying that there is none whatever!! (615/4. See "Life and Letters," II., page 387.) It is really curious to know what conceited people there are in the world (people, for instance, after looking at one Cruciferous flower, explain their homologies).

This is a nice, but most barren country, and I can find nothing to look at. Even the brooks and ponds produce nothing. The country is like Patagonia. my wife is almost well, thank God, and Leonard is wonderfully improved ...Good God, what an illness scarlet fever is! The doctor feared rheumatic fever for my wife, but she does not know her risk. It is now all over.

(FIGURE 12.)

LETTER 616. TO J.D. HOOKER. Cliff Cottage, Bournemouth, Thursday Evening {September 18th, 1862}.

Thanks for your pleasant note, which told me much news, and upon the whole good, of yourselves. You will be awfully busy for a time, but I write now to say that if you think it really worth while to send me a few Dielytra, or other Fumariaceous plant (which I have already tried in vain to find here) in a little tin box, I will try and trace the vessels; but please observe, I do not know that I shall have time, for I have just become wonderfully interested in experimenting on Drosera with poisons, etc. If you send any Fumariaceous plant, send if you can, also two or three single balsams. After writing to you, I looked at vessels of ovary of a sweet-pea, and from this and other cases I believe that in the ovary the midrib vessel alone gives homologies, and that the vessels on the edge of the carpel leaf often run into the wrong bundle, just like those on the sides of the sepals. Hence I {suppose} in Crucifers that the ovarium consists of two pistils; AA {Figure 12} being the midrib vessels, and BB being those formed of the vessels on edges of the two carpels, run together, and going to wrong bundles. I came to this conclusion before receiving your letter.

I wonder why Asa Gray will not believe in the quaternary arrangement; I had fancied that you saw some great difficulty in the case, and that made me think that my notion must be wrong.

LETTER 617. TO J.D. HOOKER. Down, September 27th {1862}.

Masdevallia turns out nothing wonderful (617/1. This may refer to the homologies of the parts. He was unable to understand the mechanism of the flower. — "Fertilisation of Orchids," Edition II., page 136.); I was merely stupid about it; I am not the less obliged for its loan, for if I had lived till 100 years old I should have been uneasy about it. It shall be returned the first day I send to Bromley. I have steamed the other plants, and made the sensitive plant very sensitive, and shall soon try some experiments on it. But after all it will only be amusement. Nevertheless, if not causing too much trouble, I should be very glad of a few young plants of this and Hedysarum in summer (617/2. Hedysarum or Desmodium gyrans, the telegraph-plant.), for this kind of work takes no time and amuses me much. Have you seeds of Oxalis sensitiva, which I see mentioned in books? By the way, what a fault it is in Henslow's "Botany" that he gives hardly any references; he alludes to great series of experiments on absorption of poison by roots, but where to find them I cannot guess. Possibly the all-knowing Oliver may know. I can plainly see that the glands of Drosera, from rapid power (almost instantaneous) of absorption and power of movement, give enormous advantage for such experiments. And some day I will enjoy myself with a good set to work; but it will be a great advantage if I can get some preliminary notion on other sensitive plants and on roots.

Oliver said he would speak about some seeds of Lythrum hyssopifolium being preserved for me. By the way, I am rather disgusted to find I cannot publish this year on Lythrum salicaria; I must make 126 additional crosses. All that I expected is true, but I have plain indication of much higher complexity. There are three pistils of different structure and functional power, and I strongly suspect altogether five kinds of pollen all different in this one species! (617/3. See "Forms of Flowers," Edition II., page 138.)

By any chance have you at Kew any odd varieties of the common potato? I want to grow a few plants of every variety, to compare flowers, leaves, fruit, etc., as I have done with peas, etc. (617/4. "Animals and Plants," Edition II., Volume I., page 346. Compare also the similar facts with regard to cabbages, loc. cit., page 342. Some of the original specimens are in the Botanical Museum at Cambridge.)