My dear Mr Darwin

I sent you about a fortnight ago copies of my paper on Phyllotaxy.¹ It took a much longer time than I believed it possibly could to get this paper through the press; but the delay was partly due to my own fault in avoiding the disagreeable work of driving the printer. The first seven pages and the last third of the paper (from p 400) would, I think, be intelligible without the intermediate mathematical discussions; or might at least furnish an adequate motive for the effort of wading through them. The diagram appended will, I believe, by graphically representing these discussions, be of some aid in making them clearer.

I have read with the greatest interest and pleasure most of the additions in the new edition of the “Origin” of which you were so kind as to send me a copy.² I was especially delighted with your discussions of Mr. Mivart’s objections.³ This was partly, perhaps, from having a recent and lively sense of his merits and abilitie⁠⟨⁠s⁠⟩⁠ got by reading two recent papers by him; his reply to Huxley, and more especially a reply to my pamphlet, which will appear in the forthcoming (April) number of our Review.⁴ It is in the form of a letter and a direct reply: I have read over the communication hastily in proof sheets, and find myself pilloried—thus early a martyr to the cause! A judicious friend thinks that the somewhat snappish tone of his comments makes them ineffective; but to me the weight of what he says seems quite disproportioned to the vigor of his style. The lawyer and the advocate are even more prominent in this paper than in his book. Passages are picked out and turned from their purpose and into ridicule in the ablest and most adroit manner. I had of course the right to make a rejoinder to so direct a reply, but I have given it up, at least for this number, though I may have something to say next July, especially on the use he makes of the old heathen atheists in his book, and defends in his reply.⁵ One point of scientific interest I have noticed, which may be worth developing. In his answer to Huxley he speaks of the action of natural selection as “fixing slight beneficial variations into enduring characters”, for which he thinks it quite incompetent; and in his reply to me he speaks of “the origin, not, of course of the slight variations, but the fixing of these in definite lines and grooves”; and this origin, he thinks, cannot be natural selection.⁶ And I believe that he is right,—that is, if the more obvious meaning of these expressions are their real ones. They appear to mean that natural selection will not account for the unvarying continuance in succeeding generations of simple changes made in individual structures (whether the change be large or small;) or will not account for the direct conversion of a simple change in a parent into a permanent alteration of its offspring. On the other hand they might possibly be taken as loose expressions of the opinion that this cause will not account for permanent changes in average characters or mid-points about which variations oscillate; and in this case I believe that he is wrong. The first and quite obvious meaning of these expressions has let in light upon his theory and his difficulties which I did not have before. They show how fundamentally the matter has been misconceived either by him or by me. I did not know that it was supposed in the theory of natural selection that variations ever become fixed by any power whatever. The effect of this cause (if I understand the theory,) is not to fix variations; though it must act to determine their averages, and limit their range; and must act indirectly to increase the useful ones and to diminish the injurious; and when these are directly opposed to each other, it must act to shift the average or normal character, instead of fixing it. What fixes species or any characters in them, (when they are fixed), is, I supposed, the continuance of the same conditions for the action of selection, together with the force of long continued inheritance. This though trite from frequent repetition appears a very difficult conception for many minds; probably on account of their retaining the old stand-point.⁷ Mr. Mivart, it would appear, is really speaking of the fixed species of the old philosophy, or about real species as they are commonly called. (Not the same as real kinds in logic.) Natural selection cannot of course account for these figments. Their true explanation is in the fact that naturalists formerly assumed without proper evidence that a change too slow for them to perceive directly could not exist and that characters so far advanced as to become permanently adapted to very general and unchanging conditions of existence, like the numbers and positions of the organs of locomotion in various animals, the whorl and the spiral arrangements of leaves in plants, and similar homological resemblances could never have been vacillating and uncertain ones. Natural Selection does not, of course, account for a fixity that does not exist, but only for the adaptations and the diversities of species, which may or may not be changing at any time. They are fixed only as the “fixed” stars are fixed, of which very many are now known to be slowly, though sensibly moving. Mivart appears to think that unless a species or a character is tied to something it will run away.

I have a little difficulty in regard to my paper on Phyllotaxy which perhaps you can help me to solve. Only fifty copies, the author’s edition, are yet ready for publication or are likely to be for some time. The others will appear in the volumes of the Memoirs.⁸ I wish to dispose of these in the most effective and economical manner; but from my ignorance of the addresses of those to whom it would be best to send them I do not feel able to do so. Dr Gray⁹ has kindly given me the addresses of some of the more eminent botanists of Europe, and I can add a few other names to the list. If you think of any men of science, especially zoologists to whom it would be well to send the paper I shall be glad to know of them. Twelve or thirteen additional copies would be all that I could thus send abroad.

Very sincerely yours | Chauncey Wright