More Letters of Charles Darwin — Volume 2

2. X.I. Miscellaneous. — 2.X.II. Melastomaceae. — 2.X.III. Correspondence with John Scott.

2. X.I. MISCELLANEOUS, 1843-1862.

(PLATE: SIR JOSEPH HOOKER, 1897. From a Photograph by W.J. Hawker Wimborne. Walker & Cockerell, ph. sc.)

LETTER 575. TO WILLIAM JACKSON HOOKER. Down, March 12th {1843}.

...When you next write to your son, will you please remember me kindly to him and give him my best thanks for his note? I had the pleasure yesterday of reading a letter from him to Mr. Lyell of Kinnordy, full of the most interesting details and descriptions, and written (if I may be permitted to make such a criticism) in a particularly agreeable style. It leads me anxiously to hope, even more than I did before, that he will publish some separate natural history journal, and not allow (if it can be avoided) his materials to be merged in another work. I am very glad to hear you talk of inducing your son to publish an Antarctic Flora. I have long felt much curiosity for some discussion on the general character of the flora of Tierra del Fuego, that part of the globe farthest removed in latitude from us. How interesting will be a strict comparison between the plants of these regions and of Scotland and Shetland. I am sure I may speak on the part of Prof. Henslow that all my collection (which gives a fair representation of the Alpine flora of Tierra del Fuego and of Southern Patagonia) will be joyfully laid at his disposal.

LETTER 576. TO JOHN LINDLEY. Down, Saturday {April 8th, 1843}.

I take the liberty, at the suggestion of Dr. Royle, of forwarding to you a few seeds, which have been found under very singular circumstances. They have been sent to me by Mr. W. Kemp, of Galashiels, a (partially educated) man, of whose acuteness and accuracy of observation, from several communications on geological subjects, I have a VERY HIGH opinion. He found them in a layer under twenty-five feet thickness of white sand, which seems to have been deposited on the margins of an anciently existing lake. These seeds are not known to the provincial botanists of the district. He states that some of them germinated in eight days after being planted, and are now alive. Knowing the interest you took in some raspberry seeds, mentioned, I remember, in one of your works, I hope you will not think me troublesome in asking you to have these seeds carefully planted, and in begging you so far to oblige me as to take the trouble to inform me of the result. Dr. Daubeny has started for Spain, otherwise I would have sent him some. Mr. Kemp is anxious to publish an account of his discovery himself, so perhaps you will be so kind as to communicate the result to me, and not to any periodical. The chance, though appearing so impossible, of recovering a plant lost to any country if not to the world, appears to me so very interesting, that I hope you will think it worth while to have these seeds planted, and not returned to me.

LETTER 577. TO C. LYELL. {September, 1843.}

An interesting fact has lately, as it were, passed through my hands. A Mr. Kemp (almost a working man), who has written on "parallel roads," and has corresponded with me (577/1. In a letter to Henslow, Darwin wrote: "If he {Mr. Kemp} had not shown himself a most careful and ingenious observer, I should have thought nothing of the case."), sent me in the spring some seeds, with an account of the spot where they were found, namely, in a layer at the bottom of a deep sand pit, near Melrose, above the level of the river, and which sand pit he thinks must have been accumulated in a lake, when the whole features of the valleys were different, ages ago; since which whole barriers of rock, it appears, must have been worn down. These seeds germinated freely, and I sent some to the Horticultural Society, and Lindley writes to me that they turn out to be a common Rumex and a species of Atriplex, which neither he nor Henslow (as I have since heard) have ever seen, and certainly not a British plant! Does this not look like a vivification of a fossil seed? It is not surprising, I think, that seeds should last ten or twenty thousand {years}, as they have lasted two or three {thousand years} in the Druidical mounds, and have germinated.

When not building, I have been working at my volume on the volcanic islands which we visited; it is almost ready for press...I hope you will read my volume, for, if you don't, I cannot think of anyone else who will! We have at last got our house and place tolerably comfortable, and I am well satisfied with our anchorage for life. What an autumn we have had: completely Chilian; here we have had not a drop of rain or a cloudy day for a month. I am positively tired of the fine weather, and long for the sight of mud almost as much as I did when in Peru.

(577/2. The vitality of seeds was a subject in which Darwin continued to take an interest. In July, 1855 ("Life and Letters," II., page 65), he wrote to Hooker: "A man told me the other day of, as I thought, a splendid instance — and splendid it was, for according to his evidence the seed came up alive out of the lower part of the London Clay! I disgusted him by telling him that palms ought to have come up."

In the "Gardeners' Chronicle," 1855, page 758, appeared a notice (half a column in length) by Darwin on the "Vitality of Seeds." The facts related refer to the "Sand-walk" at Down; the wood was planted in 1846 on a piece of pasture land laid down as grass in 1840. In 1855, on the soil being dug in several places, Charlock (Brassica sinapistrum) sprang up freely. The subject continued to interest him, and we find a note dated July 2nd, 1874, in which Darwin recorded that forty-six plants of Charlock sprang up in that year over a space (14 x 7 feet) which had been dug to a considerable depth. In the course of the article in the "Gardeners' Chronicle," Darwin remarks: "The power in seeds of retaining their vitality when buried in damp soil may well be an element in preserving the species, and therefore seeds may be specially endowed with this capacity; whereas the power of retaining vitality in a dry artificial condition must be an indirect, and in one sense accidental, quality in seeds of little or no use to the species."

The point of view expressed in the letter to Lyell above given is of interest in connection with the research of Horace Brown and F. Escombe (577/3. "Proc. Roy. Soc." Volume LXII., page 160.) on the remarkable power possessed by dry seeds of resistance to the temperature of liquid air. The point of the experiment is that life continues at a temperature "below that at which ordinary chemical reactions take place." A still more striking demonstration of the fact has been made by Thiselton-Dyer and Dewar who employed liquid hydrogen as a refrigerant. (577/4. Read before the British Association (Dover), 1899, and published in the "Comptes rendus," 1899, and in the "Proc. R. Soc." LXV., page 361, 1899.) The connection between these facts and the dormancy of buried seeds is only indirect; but inasmuch as the experiment proves the possibility of life surviving a period in which no ordinary chemical change occurs, it is clear that they help one to believe in greatly prolonged dormancy in conditions which tend to check metabolism. For a discussion of the bearing of their results on the life-problem, and for the literature of the subject, reference should be made to the paper by Brown and Escombe. See also C. de Candolle "On Latent Life in Seeds," "Brit. Assoc. Report," 1896, page 1023 and F. Escombe, "Science Progress," Volume I., N.S., page 585, 1897.)

LETTER 578. TO J.S. HENSLOW. Down, Saturday {November 5th, 1843}.

I sent that weariful Atriplex to Babington, as I said I would, and he tells me that he has reared a facsimile by sowing the seeds of A. angustifolia in rich soil. He says he knows the A. hastata, and that it is very different. Until your last note I had not heard that Mr. Kemp's seeds had produced two Polygonums. He informs me he saw each plant bring up the husk of the individual seed which he planted. I believe myself in his accuracy, but I have written to advise him not to publish, for as he collected only two kinds of seeds — and from them two Polygomuns, two species or varieties of Atriplex and a Rumex have come up, any one would say (as you suggested) that more probably all the seeds were in the soil, than that seeds, which must have been buried for tens of thousands of years, should retain their vitality. If the Atriplex had turned out new, the evidence would indeed have been good. I regret this result of poor Mr. Kemp's seeds, especially as I believed, from his statements and the appearance of the seeds, that they did germinate, and I further have no doubt that their antiquity must be immense. I am sorry also for the trouble you have had. I heard the other day through a circuitous course how you are astonishing all the clodhoppers in your whole part of the county: and {what is} far more wonderful, as it was remarked to me, that you had not, in doing this, aroused the envy of all the good surrounding sleeping parsons. What good you must do to the present and all succeeding generations. (578/1. For an account of Professor Henslow's management of his parish of Hitcham see "Memoir of the Rev. John Stevens Henslow, M.A." by the Rev. Leonard Jenyns: 8vo, London, 1862.)

LETTER 579. TO J.D. HOOKER. Down, November 14th {1855}.

You well know how credulous I am, and therefore you will not be surprised at my believing the Raspberry story (579/1. This probably refers to Lindley's story of the germination of raspberry seeds taken from a barrow 1600 years old.): a very similar case is on record in Germany — viz., seeds from a barrow; I have hardly zeal to translate it for the "Gardeners' Chronicle." (579/2. "Vitality of Seeds," "Gardeners' Chronicle," November 17th, 1855, page 758.) I do not go the whole hog — viz., that sixty and two thousand years are all the same, for I should imagine that some slight chemical change was always going on in a seed. Is this not so? The discussions have stirred me up to send my very small case of the charlock; but as it required some space to give all details, perhaps Lindley will not insert; and if he does, you, you worse than an unbelieving dog, will not, I know, believe. The reason I do not care to try Mr. Bentham's plan is that I think it would be very troublesome, and it would not, if I did not find seed, convince me myself that none were in the earth, for I have found in my salting experiments that the earth clings to the seeds, and the seeds are very difficult to find. Whether washing would do I know not; a gold-washer would succeed, I daresay.

LETTER 580. TO W.J. HOOKER.

Testimonial from Charles Darwin, Esq., M.A., F.R.S. and G.S., late Naturalist to Captain Fitz-Roy's Voyage.

Down House, Farnborough, August 25th, 1845.

I have heard with much interest that your son, Dr. Hooker, is a candidate for the Botanical Chair at Edinburgh. From my former attendance at that University, I am aware how important a post it is for the advancement of science, and I am therefore the more anxious for your son's success, from my firm belief that no one will fulfil its duties with greater zeal or ability. Since his return from the famous Antarctic expedition, I have had, as you are aware, much communication with him, with respect to the collections brought home by myself, and on other scientific subjects; and I cannot express too strongly my admiration at the accuracy of his varied knowledge, and at his powers of generalisation. From Dr. Hooker's disposition, no one, in my opinion, is more fitted to communicate to beginners a strong taste for those pursuits to which he is himself so ardently devoted. For the sake of the advancement of Botany in all its branches, your son has my warmest wishes for his success.

LETTER 581. TO J.D. HOOKER. Down, Thursday {June 11th, 1847}.

Many thanks for your kindness about the lodgings — it will be of great use to me. (581/1. The British Association met at Oxford in 1847.) Please let me know the address if Mr. Jacobson succeeds, for I think I shall go on the 22nd and write previously to my lodgings. I have since had a tempting invitation from Daubeny to meet Henslow, etc., but upon the whole, I believe, lodgings will answer best, for then I shall have a secure solitary retreat to rest in.

I am extremely glad I sent the Laburnum (581/2. This refers to the celebrated form known as Cytisus Adami, of which a full account is given in "Variation of Animals and Plants," Volume I., Edition II., page 413. It has been supposed to be a seminal hybrid or graft-hybrid between C. laburnum and C. purpureus. It is remarkable for bearing "on the same tree tufts of dingy red, bright yellow, and purple flowers, borne on branches having widely different leaves and manner of growth." In a paper by Camuzet in the "Annales de la Societe d'Horticulture de Paris, XIII., 1833, page 196, the author tries to show that Cytisus Adami is a seminal hybrid between C. alpinus and C. laburnum. Fuchs ("Sitz. k. Akad. Wien," Bd. 107) and Beijerinck ("K. Akad. Amsterdam," 1900) have spoken on Cytisus Adami, but throw no light on the origin of the hybrid. See letters to Jenner Weir in the present volume.): the raceme grew in centre of tree, and had a most minute tuft of leaves, which presented no unusual appearance: there is now on one raceme a terminal bilateral {i.e., half yellow, half purple} flower, and on other raceme a single terminal pure yellow and one adjoining bilateral flower. If you would like them I will send them; otherwise I would keep them to see whether the bilateral flowers will seed, for Herbert (581/3. Dean Herbert.) says the yellow ones will. Herbert is wrong in thinking there are no somewhat analogous facts: I can tell you some, when we meet. I know not whether botanists consider each petal and stamen an individual; if so, there seems to me no especial difficulty in the case, but if a flower-bud is a unit, are not their flowers very strange?

I have seen Dillwyn in the "Gardeners' Chronicle," and was disgusted at it, for I thought my bilateral flowers would have been a novelty for you.

(581/4. In a letter to Hooker, dated June 2nd, 1847, Darwin makes a bold suggestion as to floral symmetry: — )

I send you a tuft of the quasi-hybrid Laburnum, with two kinds of flowers on same stalk, and with what strikes {me} as very curious (though I know it has been observed before), namely, a flower bilaterally different: one other, I observe, has half its calyx purple. Is this not very curious, and opposed to the morphological idea that a flower is a condensed continuous spire of leaves? Does it not look as if flowers were normally bilateral; just in the same way as we now know that the radiating star-fish, etc., are bilateral? The case reminds me of those insects with exactly half having secondary male characters and the other half female.

(581/5. It is interesting to note his change of view in later years. In an undated letter written to Mr. Spencer, probably in 1873, he says: "With respect to asymmetry in the flowers themselves, I remain contented, from all that I have seen, with adaptation to visits of insects. There is, however, another factor which it is likely enough may have come into play — viz., the protection of the anthers and pollen from the injurious effects of rain. I think so because several flowers inhabiting rainy countries, as A. Kerner has lately shown, bend their heads down in rainy weather.")

LETTER 582. TO J.D. HOOKER. June {1855}.

(582/1. This is an early example of Darwin's interest in the movements of plants. Sleeping plants, as is well-known, may acquire a rhythmic movement differing from their natural period, but the precise experiment here described has not, as far as known, been carried out. See Pfeffer, "Periodische Bewegungen," 1875, page 32.)

I thank you much for Hedysarum: I do hope it is not very precious, for, as I told you, it is for probably a most foolish purpose. I read somewhere that no plant closes its leaves so promptly in darkness, and I want to cover it up daily for half an hour, and see if I can TEACH IT to close by itself, or more easily than at first in darkness. I am rather puzzled about its transmission, from not knowing how tender it is...

LETTER 583. TO J.D. HOOKER. Down, July 19th, 1856.

I thank you warmly for the very kind manner with which you have taken my request. It will, in truth, be a most important service to me; for it is absolutely necessary that I should discuss single and double creations, as a very crucial point on the general origin of species, and I must confess, with the aid of all sorts of visionary hypotheses, a very hostile one. I am delighted that you will take up possibility of crossing, no botanist has done so, which I have long regretted, and I am glad to see that it was one of A. De Candolle's desiderata. By the way, he is curiously contradictory on subject. I am far from expecting that no cases of apparent impossibility will be found; but certainly I expect that ultimately they will disappear; for instance, Campanulaceae seems a strong case, but now it is pretty clear that they must be liable to crossing. Sweet-peas (583/1. In Lathyrus odoratus the absence of the proper insect has been supposed to prevent crossing. See "Variation under Domestication," Edition II., Volume II., page 68; but the explanation there given for Pisum may probably apply to Lathyrus.), bee-orchis, and perhaps hollyhocks are, at present, my greatest difficulties; and I find I cannot experimentise by castrating sweet-peas, without doing fatal injury. Formerly I felt most interest on this point as one chief means of eliminating varieties; but I feel interest now in other ways. One general fact {that} makes me believe in my doctrine (583/2. The doctrine which has been epitomised as "Nature abhors perpetual self-fertilisation," and is generally known as Knight's Law or the Knight-Darwin Law, is discussed by Francis Darwin in "Nature," 1898. References are there given to the chief passages in the "Origin of Species," etc., bearing on the question. See Letter 19, Volume I.), is that NO terrestrial animal in which semen is liquid is hermaphrodite except with mutual copulation; in terrestrial plants in which the semen is dry there are many hermaphrodites. Indeed, I do wish I lived at Kew, or at least so that I could see you oftener. To return again to subject of crossing: I have been inclined to speculate so far, as to think (my!?) notion (I say MY notion, but I think others have put forward nearly or quite similar ideas) perhaps explains the frequent separation of the sexes in trees, which I think I have heard remarked (and in looking over the mono- and dioecious Linnean classes in Persoon seems true) are very apt to have sexes separated; for {in} a tree having a vast number of flowers on the same individual, or at least the same stock, each flower, if only hermaphrodite on the common plan, would generally get its own pollen or only pollen from another flower on same stock, — whereas if the sexes were separate there would be a better chance of occasional pollen from another distinct stock. I have thought of testing this in your New Zealand Flora, but I have no standard of comparison, and I found myself bothered by bushes. I should propound that some unknown causes had favoured development of trees and bushes in New Zealand, and consequent on this there had been a development of separation of sexes to prevent too much intermarriage. I do not, of course, suppose the prevention of too much intermarriage the only good of separation of sexes. But such wild notions are not worth troubling you with the reading of.

LETTER 584. TO J.D. HOOKER. Moor Park {May 2nd, 1857}.

The most striking case, which I have stumbled on, on apparent, but false relation of structure of plants to climate, seems to be Meyer and Doege's remark that there is not one single, even moderately-sized, family at the Cape of Good Hope which has not one or several species with heath-like foliage; and when we consider this together with the number of true heaths, any one would have been justified, had it not been for our own British heaths (584/1. It is well known that plants with xerophytic characteristics are not confined to dry climates; it is only necessary to mention halophytes, alpine plants and certain epiphytes. The heaths of Northern Europe are placed among the xerophytes by Warming ("Lehrbuch der okologischen Pflanzengeographie," page 234, Berlin, 1896).), in saying that heath-like foliage must stand in direct relation to a dry and moderately warm climate. Does this not strike you as a good case of false relation? I am so pleased with this place and the people here, that I am greatly tempted to bring Etty here, for she has not, on the whole, derived any benefit from Hastings. With thanks for your never failing assistance to me...

I remember that you were surprised at number of seeds germinating in pond mud. I tried a fourth pond, and took about as much mud (rather more than in former case) as would fill a very large breakfast cup, and before I had left home 118 plants had come up; how many more will be up on my return I know not. This bears on chance of birds by their muddy feet transporting fresh-water plants.

This would not be a bad dodge for a collector in country when plants were not in seed, to collect and dry mud from ponds.

LETTER 585. TO ASA GRAY. Down {1857}.

I am very glad to hear that you think of discussing the relative ranges of the identical and allied U. States and European species, when you have time. Now this leads me to make a very audacious remark in opposition to what I imagine Hooker has been writing (585/1. See Letter 338, Volume I.), and to your own scientific conscience. I presume he has been urging you to finish your great "Flora" before you do anything else. Now I would say it is your duty to generalise as far as you safely can from your as yet completed work. Undoubtedly careful discrimination of species is the foundation of all good work; but I must look at such papers as yours in Silliman as the fruit. As careful observation is far harder work than generalisation, and still harder than speculation, do you not think it very possible that it may be overvalued? It ought never to be forgotten that the observer can generalise his own observations incomparably better than any one else. How many astronomers have laboured their whole lives on observations, and have not drawn a single conclusion; I think it is Herschel who has remarked how much better it would be if they had paused in their devoted work and seen what they could have deduced from their work. So do pray look at this side of the question, and let us have another paper or two like the last admirable ones. There, am I not an audacious dog!

You ask about my doctrine which led me to expect that trees would tend to have separate sexes. I am inclined to believe that no organic being exists which perpetually self-fertilises itself. This will appear very wild, but I can venture to say that if you were to read my observations on this subject you would agree it is not so wild as it will at first appear to you, from flowers said to be always fertilised in bud, etc. It is a long subject, which I have attended to for eighteen years. Now, it occurred to me that in a large tree with hermaphrodite flowers, we will say it would be ten to one that it would be fertilised by the pollen of its own flower, and a thousand or ten thousand to one that if crossed it would be crossed only with pollen from another flower of same tree, which would be opposed to my doctrine. Therefore, on the great principle of "Nature not lying," I fully expected that trees would be apt to be dioecious or monoecious (which, as pollen has to be carried from flower to flower every time, would favour a cross from another individual of the same species), and so it seems to be in Britain and New Zealand. Nor can the fact be explained by certain families having this structure and chancing to be trees, for the rule seems to hold both in genera and families, as well as in species.

I give you full permission to laugh your fill at this wild speculation; and I do not pretend but what it may be chance which, in this case, has led me apparently right. But I repeat that I feel sure that my doctrine has more probability than at first it appears to have. If you had not asked, I should not have written at such length, though I cannot give any of my reasons.

The Leguminosae are my greatest opposers: yet if I were to trust to observations on insects made during many years, I should fully expect crosses to take place in them; but I cannot find that our garden varieties ever cross each other. I do NOT ask you to take any trouble about it, but if you should by chance come across any intelligent nurseryman, I wish you would enquire whether they take any pains in raising the varieties of papilionaceous plants apart to prevent crossing. (I have seen a statement of naturally formed crossed Phaseoli near N. York.) The worst is that nurserymen are apt to attribute all varieties to crossing.

Finally I incline to believe that every living being requires an occasional cross with a distinct individual; and as trees from the mere multitude of flowers offer an obstacle to this, I suspect this obstacle is counteracted by tendency to have sexes separated. But I have forgotten to say that my maximum difficulty is trees having papilionaceous flowers: some of them, I know, have their keel-petals expanded when ready for fertilisation; but Bentham does not believe that this is general: nevertheless, on principle of nature not lying, I suspect that this will turn out so, or that they are eminently sought by bees dusted with pollen. Again I do NOT ask you to take trouble, but if strolling under your Robinias when in full flower, just look at stamens and pistils whether protruded and whether bees visit them. I must just mention a fact mentioned to me the other day by Sir W. Macarthur, a clever Australian gardener: viz., how odd it was that his Erythrinas in N.S. Wales would not set a seed, without he imitated the movements of the petals which bees cause. Well, as long as you live, you will never, after this fearfully long note, ask me why I believe this or that.

LETTER 586. TO ASA GRAY. June 18th {1857}.

It has been extremely kind of you telling me about the trees: now with your facts, and those from Britain, N. Zealand, and Tasmania I shall have fair materials for judging. I am writing this away from home, but I think your fraction of 95/132 is as large as in other cases, and is at least a striking coincidence.

I thank you much for your remarks about my crossing notions, to which, I may add, I was led by exactly the same idea as yours, viz., that crossing must be one means of eliminating variation, and then I wished to make out how far in animals and vegetables this was possible. Papilionaceous flowers are almost dead floorers to me, and I cannot experimentise, as castration alone often produces sterility. I am surprised at what you say about Compositae and Gramineae. From what I have seen of latter they seemed to me (and I have watched wheat, owing to what L. de Longchamps has said on their fertilisation in bud) favourable for crossing; and from Cassini's observations and Kolreuter's on the adhesive pollen, and C.C. Sprengel's, I had concluded that the Compositae were eminently likely (I am aware of the pistil brushing out pollen) to be crossed. (586/1. This is an instance of the curious ignorance of the essential principles of floral mechanism which was to be found even among learned and accomplished botanists such as Gray, before the publication of the "Fertilisation of Orchids." Even in 1863 we find Darwin explaining the meaning of dichogamy in a letter to Gray.) If in some months' time you can find time to tell me whether you have made any observations on the early fertilisation of plants in these two orders, I should be very glad to hear, as it would save me from great blunder. In several published remarks on this subject in various genera it has seemed to me that the early fertilisation has been inferred from the early shedding of the pollen, which I think is clearly a false inference. Another cause, I should think, of the belief of fertilisation in the bud, is the not-rare, abnormal, early maturity of the pistil as described by Gartner. I have hitherto failed in meeting with detailed accounts of regular and normal impregnation in the bud. Podostemon and Subularia under water (and Leguminosae) seem and are strongest cases against me, as far as I as yet know. I am so sorry that you are so overwhelmed with work; it makes your VERY GREAT kindness to me the more striking.

It is really pretty to see how effectual insects are. A short time ago I found a female holly sixty measured yards from any other holly, and I cut off some twigs and took by chance twenty stigmas, cut off their tops, and put them under the microscope: there was pollen on every one, and in profusion on most! weather cloudy and stormy and unfavourable, wind in wrong direction to have brought any.

LETTER 587. TO J.D. HOOKER. Down, January 12th {1858}.

I want to ask a question which will take you only few words to answer. It bears on my former belief (and Asa Gray strongly expressed opinion) that Papilionaceous flowers were fatal to my notion of there being no eternal hermaphrodites. First let me say how evidence goes. You will remember my facts going to show that kidney-beans require visits of bees to be fertilised. This has been positively stated to be the case with Lathyrus grandiflorus, and has been very partially verified by me. Sir W. Macarthur tells me that Erythrina will hardly seed in Australia without the petals are moved as if by bee. I have just met the statement that, with common bean, when the humble-bees bite holes at the base of the flower, and therefore cease visiting the mouth of the corolla, "hardly a bean will set." But now comes a much more curious statement, that {in} 1842-43, "since bees were established at Wellington (New Zealand), clover seeds all over the settlement, WHICH IT DID NOT BEFORE." (587/1. See Letter 362, Volume I.) The writer evidently has no idea what the connection can be. Now I cannot help at once connecting this statement (and all the foregoing statements in some degree support each other, as all have been advanced without any sort of theory) with the remarkable absence of Papilionaceous plants in N. Zealand. I see in your list Clianthus, Carmichaelia (four species), a new genus, a shrub, and Edwardsia (is latter Papilionaceous?). Now what I want to know is whether any of these have flowers as small as clover; for if they have large flowers they may be visited by humble-bees, which I think I remember do exist in New Zealand; and which humble-bees would not visit the smaller clover. Even the very minute little yellow clover in England has every flower visited and revisited by hive-bees, as I know by experience. Would it not be a curious case of correlation if it could be shown to be probable that herbaceous and small Leguminosae do not exist because when {their} seeds {are} washed ashore (!!!) no small bees exist there. Though this latter fact must be ascertained. I may not prove anything, but does it not seem odd that so many quite independent facts, or rather statements, should point all in one direction, viz., that bees are necessary to the fertilisation of Papilionaceous flowers?

LETTER 588. TO JOHN LUBBOCK (Lord Avebury). Sunday {1859}.