Life and Letters of Charles Darwin Volume I Part 41

P.S.--I do not know how far you will care to hear, but I find Moquin-Tandon treats in his 'Teratologie' on villosity of plants, and seems to attribute more to dryness than alt.i.tude; but seems to think that it must be admitted that mountain plants are villose, and that this villosity is only in part explained by De Candolle's remark that the dwarfed condition of mountain plants would condense the hairs, and so give them the APPEARANCE of being more hairy. He quotes Senebier, 'Physiologie Vegetale,' as authority--I suppose the first authority, for mountain plants being hairy.

If I could show positively that the endemic species were more hairy in dry districts, then the case of the varieties becoming more hairy in dry ground would be a fact for me.

CHARLES DARWIN TO J.D. HOOKER. Down, June 3rd [1857].

My dear Hooker,

I am going to enjoy myself by having a prose on my own subjects to you, and this is a greater enjoyment to me than you will readily understand, as I for months together do not open my mouth on Natural History.

Your letter is of great value to me, and staggers me in regard to my proposition. I dare say the absence of botanical facts may in part be accounted for by the difficulty of measuring slight variations. Indeed, after writing, this occurred to me; for I have Crucianella stylosa coming into flower, and the pistil ought to be very variable in length, and thinking of this I at once felt how could one judge whether it was variable in any high degree. How different, for instance, from the beak of a bird! But I am not satisfied with this explanation, and am staggered. Yet I think there is something in the law; I have had so many instances, as the following: I wrote to Wollaston to ask him to run through the Madeira Beetles and tell me whether any one presented anything very anomalous in relation to its allies. He gave me a unique case of an enormous head in a female, and then I found in his book, already stated, that the size of the head was ASTONIs.h.i.+NGLY variable.

Part of the difference with plants may be accounted for by many of my cases being secondary male or FEMALE characters, but then I have striking cases with hermaphrodite Cirripedes. The cases seem to me far too numerous for accidental coincidences, of great variability and abnormal development. I presume that you will not object to my putting a note saying that you had reflected over the case, and though one or two cases seemed to support, quite as many or more seemed wholly contradictory. This want of evidence is the more surprising to me, as generally I find any proposition more easily tested by observations in botanical works, which I have picked up, than in zoological works. I never dreamed that you had kept the subject at all before your mind. Altogether the case is one more of my MANY horrid puzzles. My observations, though on so infinitely a small scale, on the struggle for existence, begin to make me see a little clearer how the fight goes on.

Out of sixteen kinds of seed sown on my meadow, fifteen have germinated, but now they are peris.h.i.+ng at such a rate that I doubt whether more than one will flower. Here we have choking which has taken place likewise on a great scale, with plants not seedlings, in a bit of my lawn allowed to grow up. On the other hand, in a bit of ground, 2 by 3 feet, I have daily marked each seedling weed as it has appeared during March, April and May, and 357 have come up, and of these 277 have ALREADY been killed chiefly by slugs. By the way, at Moor Park, I saw rather a pretty case of the effects of animals on vegetation: there are enormous commons with clumps of old Scotch firs on the hills, and about eight or ten years ago some of these commons were enclosed, and all round the clumps nice young trees are springing up by the million, looking exactly as if planted, so many are of the same age. In other parts of the common, not yet enclosed, I looked for miles and not ONE young tree could be seen.

I then went near (within quarter of a mile of the clumps) and looked closely in the heather, and there I found tens of thousands of young Scotch firs (thirty in one square yard) with their tops nibbled off by the few cattle which occasionally roam over these wretched heaths. One little tree, three inches high, by the rings appeared to be twenty-six years old, with a short stem about as thick as a stick of sealing-wax.

What a wondrous problem it is, what a play of forces, determining the kind and proportion of each plant in a square yard of turf! It is to my mind truly wonderful. And yet we are pleased to wonder when some animal or plant becomes extinct.

I am so sorry that you will not be at the Club. I see Mrs. Hooker is going to Yarmouth; I trust that the health of your children is not the motive. Good-bye.

My dear Hooker, ever yours, C. DARWIN.

P.S.--I believe you are afraid to send me a ripe Edwardsia pod, for fear I should float it from New Zealand to Chile!!!

CHARLES DARWIN TO J.D. HOOKER. Down, June 5 [1857].

My dear Hooker,

I honour your conscientious care about the medals. (The Royal Society's medals.) Thank G.o.d! I am only an amateur (but a much interested one) on the subject.

It is an old notion of mine that more good is done by giving medals to younger men in the early part of their career, than as a mere reward to men whose scientific career is nearly finished. Whether medals ever do any good is a question which does not concern us, as there the medals are. I am almost inclined to think that I would rather lower the standard, and give medals to young workers than to old ones with no ESPECIAL claims. With regard to especial claims, I think it just deserving your attention, that if general claims are once admitted, it opens the door to great laxity in giving them. Think of the case of a very rich man, who aided SOLELY with his money, but to a grand extent--or such an inconceivable prodigy as a minister of the Crown who really cared for science. Would you give such men medals? Perhaps medals could not be better applied than EXCLUSIVELY to such men. I confess at present I incline to stick to especial claims which can be put down on paper...

I am much confounded by your showing that there are not obvious instances of my (or rather Waterhouse's) law of abnormal developments being highly variable. I have been thinking more of your remark about the difficulty of judging or comparing variability in plants from the great general variability of parts. I should look at the law as more completely smashed if you would turn in your mind for a little while for cases of great variability of an organ, and tell me whether it is moderately easy to pick out such cases; For IF THEY CAN BE PICKED OUT, and, notwithstanding, do not coincide with great or abnormal development, it would be a complete smasher. It is only beginning in your mind at the variability end of the question instead of at the abnormality end. PERHAPS cases in which a part is highly variable in all the species of a group should be excluded, as possibly being something distinct, and connected with the perplexing subject of polymorphism.

Will you perfect your a.s.sistance by further considering, for a little, the subject this way?

I have been so much interested this morning in comparing all my notes on the variation of the several species of the genus Equus and the results of their crossing. Taking most strictly a.n.a.logous facts amongst the blessed pigeons for my guide, I believe I can plainly see the colouring and marks of the grandfather of the a.s.s, Horse, Quagga, Hemionus and Zebra, some millions of generations ago! Should not I [have] sneer[ed]

at any one who made such a remark to me a few years ago; but my evidence seems to me so good that I shall publish my vision at the end of my little discussion on this genus.

I have of late inundated you with my notions, you best of friends and philosophers.

Adios, C. DARWIN.

CHARLES DARWIN TO J.D. HOOKER. Moor Park, Farnham, June 25th [1857].

My dear Hooker,

This requires no answer, but I will ask you whenever we meet. Look at enclosed seedling gorses, especially one with the top knocked off. The leaves succeeding the cotyledons being almost clover-like in shape, seems to me feebly a.n.a.logous to embryonic resemblances in young animals, as, for instance, the young lion being striped. I shall ask you whether this is so...(See 'Power of Movement in Plants,' page 414.)

Dr. Lane (The physician at Moor Park.) and wife, and mother-in-law, Lady Drysdale, are some of the nicest people I ever met.

I return home on the 30th. Good-bye, my dear Hooker.

Ever yours, C. DARWIN.

[Here follows a group of letters, of various dates, bearing on the question of large genera varying.]

CHARLES DARWIN TO J.D. HOOKER. March 11th [1858].

I was led to all this work by a remark of Fries, that the species in large genera were more closely related to each other than in small genera; and if this were so, seeing that varieties and species are so hardly distinguishable, I concluded that I should find more varieties in the large genera than in the small...Some day I hope you will read my short discussion on the whole subject. You have done me infinite service, whatever opinion I come to, in drawing my attention to at least the possibility or the probability of botanists recording more varieties in the large than in the small genera. It will be hard work for me to be candid in coming to my conclusion.

Ever yours, most truly, C. DARWIN.

P.S.--I shall be several weeks at my present job. The work has been turning out badly for me this morning, and I am sick at heart; and, oh!

how I do hate species and varieties.

CHARLES DARWIN TO J.D. HOOKER. July 14th [1857?].

...I write now to supplicate most earnestly a favour, viz., the loan of "Boreau, Flore du centre de la France", either 1st or 2nd edition, last best; also "Flora Ratisbonensis," by Dr. Furnrohr, in 'Naturhist.

Topographie von Regensburg, 1839.' If you can POSSIBLY spare them, will you send them at once to the enclosed address. If you have not them, will you send one line by return of post: as I must try whether Kippist (The late Mr. Kippist was at this time in charge of the Linnean Society's Library.) can anyhow find them, which I fear will be nearly impossible in the Linnean Library, in which I know they are.

I have been making some calculations about varieties, etc., and talking yesterday with Lubbock, he has pointed out to me the grossest blunder which I have made in principle, and which entails two or three weeks'

lost work; and I am at a dead-lock till I have these books to go over again, and see what the result of calculation on the right principle is.

I am the most miserable, bemuddled, stupid dog in all England, and am ready to cry with vexation at my blindness and presumption.

Ever yours, most miserably, C. DARWIN.

CHARLES DARWIN TO JOHN LUBBOCK. Down, [July] 14th [1857].

My dear Lubbock,

You have done me the greatest possible service in helping me to clarify my brains. If I am as muzzy on all subjects as I am on proportion and chance,--what a book I shall produce!

I have divided the New Zealand Flora as you suggested, there are 329 species in genera of 4 and upwards, and 323 in genera of 3 and less.

The 339 species have 51 species presenting one or more varieties. The 323 species have only 37. Proportionately (339: 323:: 51: 48.5) they ought to have had 48 1/2 species presenting vars. So that the case goes as I want it, but not strong enough, without it be general, for me to have much confidence in. I am quite convinced yours is the right way; I had thought of it, but should never have done it had it not been for my most fortunate conversation with you.

Un quite shocked to find how easily I am muddled, for I had before thought over the subject much, and concluded my way was fair. It is dreadfully erroneous.

What a disgraceful blunder you have saved me from. I heartily thank you.

Ever yours, C. DARWIN.

P.S.--It is enough to make me tear up all my MS. and give up in despair.

It will take me several weeks to go over all my materials. But oh, if you knew how thankful I am to you!