Volume I Part 52 (1/2)
Salix, I really know nothing about.
Rubus, the N. American species, with one exception, are very clearly marked indeed.
Mentha, we have only one wild species; that has two pretty well-marked forms, which have been taken for species; one smooth, the other hairy.
Saxifraga, gives no trouble here.
Myosotis, only one or two species here, and those very well marked.
Hieracium, few species, but pretty well marked.
Rosa, putting down a set of nominal species, leaves us four; two of them polymorphous, but easy to distinguish...
LETTER 339. TO J.D. HOOKER. Down, [1857?]
One must judge by one's own light, however imperfect, and as I have found no other book (339/1. A. De Candolle's ”Geographie Botanique,”
1855.) so useful to me, I am bound to feel grateful: no doubt it is in main part owing to the concentrated light of the n.o.ble art of compilation. (339/2. See Letter 49.) I was aware that he was not the first who had insisted on range of Monocots. (Was not R. Brown [with]
Flinders?) (339/3. M. Flinders' ”Voyage to Terra Australis in 1801-3, in H.M.S. 'Investigator'”; with ”Botanical Appendix,” by Robert Brown, London, 1814.), and I fancy I only used expression ”strongly insisted on,”--but it is quite unimportant.
If you and I had time to waste, I should like to go over his [De Candolle's] book and point out the several subjects in which I fancy he is original. His remarks on the relations of naturalised plants will be very useful to me; on the ranges of large families seemed to me good, though I believe he has made a great blunder in taking families instead of smaller groups, as I have been delighted to find in A. Gray's last paper. But it is no use going on.
I do so wish I could understand clearly why you do not at all believe in accidental means of dispersion of plants. The strongest argument which I can remember at this instant is A. de C., that very widely ranging plants are found as commonly on islands as over continents. It is really provoking to me that the immense contrast in proportion of plants in New Zealand and Australia seems to me a strong argument for non-continuous land; and this does not seem to weigh in the least with you. I wish I could put myself in your frame of mind. In Madeira I find in Wollaston's books a parallel case with your New Zealand case--viz., the striking absence of whole genera and orders now common in Europe, and (as I have just been hunting out) common in Europe in Miocene periods. Of course I can offer no explanation why this or that group is absent; but if the means of introduction have been accidental, then one might expect odd proportions and absences. When we meet, do try and make me see more clearly than I do, your reasons.
LETTER 340. TO J.D. HOOKER. Down, November 14th [1858].
I am heartily glad to hear that my Lyellian notes have been of the slightest use to you. (340/1. The Copley Medal was given to Sir Charles Lyell in 1858. Mr. Darwin supplied Sir J.D. Hooker, who was on the Council of the Royal Society, with notes for the reasons for the award.
See Letter 69.) I do not think the view is exaggerated...
Your letter and lists have MOST DEEPLY interested me. First for less important point, about hermaphrodite trees. (340/2. See ”Life and Letters,” II., page 89. In the ”Origin,” Edition I., page 100, the author quotes Dr. Hooker to the effect that ”the rule does not hold in Australia,” i.e., that trees are not more generally unis.e.xual than other plants. In the 6th edition, page 79, Darwin adds, ”but if most of the Australian trees are dichogamous, the same result would follow as if they bore flowers with separated s.e.xes.”) It is enough to knock me down, yet I can hardly think that British N. America and New Zealand should all have been theoretically right by chance. Have you at Kew any Eucalyptus or Australian Mimosa which sets its seeds? if so, would it be very troublesome to observe when pollen is mature, and whether pollen-tubes enter stigma readily immediately that pollen is mature or some little time afterwards? though if pollen is not mature for some little time after flower opens, the stigma might be ready first, though according to C.C. Sprengel this is a rarer case. I wrote to Muller for chance of his being able and willing to observe this.
Your fact of greater number of European plants (N.B.--But do you mean greater percentage?) in Australia than in S. America is astounding and very unpleasant to me; for from N.W. America (where nearly the same flora exists as in Canada?) to T. del Fuego, there is far more continuous high land than from Europe to Tasmania. There must have, I should think, existed some curious barrier on American High-Road: dryness of Peru, excessive damp of Panama, or some other confounded cause, which either prevented immigration or has since destroyed them.
You say I may ask questions, and so I have on enclosed paper; but it will of course be a very different thing whether you will think them worth labour of answering.
May I keep the lists now returned? otherwise I will have them copied.
You said that you would give me a few cases of Australian forms and identical species going north by Malay Archipelago mountains to Philippines and j.a.pan; but if these are given in your ”Introduction”
this will suffice for me. (340/3. See Hooker's ”Introductory Essay,”
page l.)
Your lists seem to me wonderfully interesting.
According to my theoretical notions, I am not satisfied with what you say about local plants in S.W. corner of Australia (340/4. Sir Joseph replied in an undated letter: ”Thanks for your hint. I shall be very cautious how I mention any connection between the varied flora and poor soil of S.W. Australia...It is not by the way only that the species are so numerous, but that these and the genera are so confoundedly well marked. You have, in short, an incredible number of VERY LOCAL, WELL MARKED genera and species crowded into that corner of Australia.” See ”Introductory Essay to the Flora of Tasmania,” 1859, page li.), and the seeds not readily germinating: do be cautious on this; consider lapse of time. It does not suit my stomach at all. It is like Wollaston's confined land-snails in Porto Santo, and confined to same spots since a Tertiary period, being due to their slow crawling powers; and yet we know that other sh.e.l.l-snails have stocked a whole country within a very few years with the same breeding powers, and same crawling powers, when the conditions have been favourable to the life of the introduced species. Hypothetically I should rather look at the case as owing to--but as my notions are not very simple or clear, and only hypothetical, they are not worth inflicting on you.
I had vowed not to mention my everlasting Abstract (340/5. The ”Origin of Species” was abbreviated from the MS. of an unpublished book.) to you again, for I am sure I have bothered you far more than enough about it; but as you allude to its previous publication I may say that I have chapters on Instinct and Hybridism to abstract, which may take a fortnight each; and my materials for Palaeontology, Geographical Distribution and Affinities being less worked up, I daresay each of these will take me three weeks, so that I shall not have done at soonest till April, and then my Abstract will in bulk make a small volume. I never give more than one or two instances, and I pa.s.s over briefly all difficulties, and yet I cannot make my Abstract shorter, to be satisfactory, than I am now doing, and yet it will expand to small volume.
LETTER 341. TO J.D. HOOKER. Down [November?] 27th [1858].