Adios. I was really consummately impudent to express my opinion "on the retrograde step" ("To imagine such enormous geological changes within the period of the existence of now living beings, on no other ground but to account for their distribution, seems to me, in our present state of ignorance on the means of transportal, an almost retrograde step in science."—Extract from the paper on 'Salt Water and Seeds' in "Gardeners' Chronicle", May 26, 1855.), and I deserved a good snub, and upon reflection I am very glad you did not answer me in "Gardeners' Chronicle".
I have been VERY MUCH interested with the Florula. (Godron's 'Florula Juvenalis,' which gives an interesting account of plants introduced in imported wool.)
[Writing on June 5th to Sir J.D. Hooker, my father mentions a letter from Dr. Asa Gray. The letter referred to was an answer to the following:]
CHARLES DARWIN TO ASA GRAY. (The well-known American Botanist. My father's friendship with Dr. Gray began with the correspondence of which the present is the first letter. An extract from a letter to Sir J. Hooker, 1857, shows that my father's strong personal regard for Dr. Gray had an early origin: "I have been glad to see A. Gray's letters; there is always something in them that shows that he is a very lovable man.") Down, April 25th [1855].
My dear Sir,
I hope that you will remember that I had the pleasure of being introduced to you at Kew. I want to beg a great favour of you, for which I well know I can offer no apology. But the favour will not, I think, cause you much trouble, and will greatly oblige me. As I am no botanist, it will seem so absurd to you my asking botanical questions; that I may premise that I have for several years been collecting facts on "variation," and when I find that any general remark seems to hold good amongst animals, I try to test it in Plants. [Here follows a request for information on American Alpine plants, and a suggestion as to publishing on the subject.] I can assure you that I perceive how presumptuous it is in me, not a botanist, to make even the most trifling suggestion to such a botanist as yourself; but from what I saw and have heard of you from our dear and kind friend Hooker, I hope and think you will forgive me, and believe me, with much respect,
Dear sir, yours very faithfully, CHARLES DARWIN.
CHARLES DARWIN TO ASA GRAY. Down, June 8th [1855].
My dear Sir,
I thank you cordially for your remarkably kind letter of the 22d. ult., and for the extremely pleasant and obliging manner in which you have taken my rather troublesome questions. I can hardly tell you how much your list of Alpine plants has interested me, and I can now in some degree picture to myself the plants of your Alpine summits. The new edition of your Manual is CAPITAL news for me. I know from your preface how pressed you are for room, but it would take no space to append (Eu) in brackets to any European plant, and, as far as I am concerned, this would answer every purpose. (This suggestion Dr. Gray adopted in subsequent editions.) From my own experience, whilst making out English plants in our manuals, it has often struck me how much interest it would give if some notion of their range had been given; and so, I cannot doubt, your American inquirers and beginners would much like to know which of their plants were indigenous and which European. Would it not be well in the Alpine plants to append the very same addition which you have now sent me in MS.? though here, owing to your kindness, I do not speak selfishly, but merely pro bono Americano publico. I presume it would be too troublesome to give in your manual the habitats of those plants found west of the Rocky Mountains, and likewise those found in Eastern Asia, taking the Yenesei (?),—which, if I remember right, according to Gmelin, is the main partition line of Siberia. Perhaps Siberia more concerns the northern Flora of North America. The ranges of plants to the east and west, viz., whether most found are in Greenland and Western Europe, or in E. Asia, appears to me a very interesting point as tending to show whether the migration has been eastward or westward. Pray believe me that I am most entirely conscious that the ONLY USE of these remarks is to show a botanist what points a non-botanist is curious to learn; for I think every one who studies profoundly a subject often becomes unaware [on] what points the ignorant require information. I am so very glad that you think of drawing up some notice on your geographical distribution, for the air of the Manual strikes me as in some points better adapted for comparison with Europe than that of the whole of North America. You ask me to state definitely some of the points on which I much wish for information; but I really hardly can, for they are so vague; and I rather wish to see what results will come out from comparisons, than have as yet defined objects. I presume that, like other botanists, you would give, for your area, the proportion (leaving out introduced plants) to the whole of the great leading families: this is one point I had intended (and, indeed, have done roughly) to tabulate from your book, but of course I could have done it only VERY IMPERFECTLY. I should also, of course, have ascertained the proportion, to the whole Flora, of the European plants (leaving out introduced) AND OF THE SEPARATE GREAT FAMILIES, in order to speculate on means of transportal. By the way, I ventured to send a few days ago a copy of the "Gardeners' Chronicle" with a short report by me of some trifling experiments which I have been trying on the power of seeds to withstand sea water. I do not know whether it has struck you, but it has me, that it would be advisable for botanists to give in WHOLE NUMBERS, as well as in the lowest fraction, the proportional numbers of the families, thus I make out from your Manual that of the INDIGENOUS plants the proportion of the Umbelliferae are 36/1798 = 1/49; for, without one knows the WHOLE numbers, one cannot judge how really close the numbers of the plants of the same family are in two distant countries; but very likely you may think this superfluous. Mentioning these proportional numbers, I may give you an instance of the sort of points, and how vague and futile they often are, which I ATTEMPT to work out...; reflecting on R. Brown's and Hooker's remark, that near identity of proportional numbers of the great families in two countries, shows probably that they were once continuously united, I thought I would calculate the proportions of, for instance, the INTRODUCED Compositae in Great Britain to all the introduced plants, and the result was, 10/92 = 1/9.2. In our ABORIGINAL or indigenous flora the proportion is 1/10; and in many other cases I found an equally striking correspondence. I then took your Manual, and worked out the same question; here I find in the Compositae an almost equally striking correspondence, viz. 24/206 = 1/8 in the introduced plants, and 223/1798 = 1/8 in the indigenous; but when I came to the other families I found the proportion entirely different, showing that the coincidences in the British Flora were probably accidental!