My dear Romanes.

My M.S. on worms has been sent to Printers, so I am going to amuse myself by scribbling to you on a few points; but you must not waste your time in answering at any length this scribble.—¹

Firstly,—your letter on intelligence was very useful to me, & I tore up & rewrote what I sent you. I have not attempted to define intelligence, but have quoted your remarks on experience, & have shown how far they apply to worms.— It seems to me that they must be said to work with some intelligence, anyhow they are not guided by a blind instinct.²

Secondly, I was greatly interested by the abstract in Nature of your work on Echinoderms: the complexity, with simplicity & with such curious coordination of the nervous system is marvellous; & you showed me before what splendid gymnastic feats they can perform.—³

Thirdly, D^r Roux has sent me a book just published by him “Der Kampf der Theile &c” 1881.—(240 pages in length)⁴ He is manifestly a well read physiologist & pathologist & from his position a good anatomist. It is full of reasoning & this in German is very difficult to me, so that I have only skimmed through each page,—here & there reading with a little more care. As far as I can imperfectly judge it is the most important book on Evolution, which has appeared for some time. I believe that G. H. Lewis hinted at the same fundamental idea, viz that there is a struggle going on within every organism between the organic molecules, the cells & the organs.⁵ I think that his basis is that every cell which best performs its function is as consequence at the same time best nourished & best propagates its kind. The book does not touch on mental phenomena, but there is much discussion on rudimentary or atrophied parts, to which subject you formerly attended.— Now if you would like to read this book, I would send it, after Frank has glanced at it, for I do not think he will have time to read it with care.— If you read it & are struck with it (but I may be wholly mistaken about its value), you would do a public service by analysing and criticising it in Nature.⁶ D^r. Roux makes, I think, a gigantic oversight in never considering plants: these would simplify the problem for him.—

Fourthly, I do not know whether you will discuss in your book on the Mind of Animals, any of the more complex & wonderful instincts. It is unsatisfactory work, as there can be no fossilised instincts, & the sole guide is their state in other members of the same order & mere probability

But if you do discuss any (& it will perhaps be expected of you) I sh^d. think that you could not select a better case than that of the sand-wasps which paralyse their prey, as formerly described by Fabre in his wonderful paper in annl des Sc., & since amplified in his admirable ‘Souvenirs’.⁷

Whilst reading this latter book, I speculated a little on the subject. Astonishing nonsense is often spoken of the sand-wasp’s knowledge of anatomy. Now will anyone say that a Gauchos on the plains of La Plata have such knowledge, yet I have often seen them pith a struggling & lassoed cow on the ground with unerring skill, which no mere anatomist could imitate. The pointed knife was infallibly driven in between the vertebræ by a single slight thrust. I presume that the art was first discovered by chance, & that each young Gaucho sees exactly how the others do it & then with a very little practice learns the art.—⁸ Now I suppose that the sand-wasps originally merely killed their prey by stinging them in many places (see p. 129 of Fabre Souvenir & p. 241) on the lower & softer side of the body, & that to sting a certain segment was found by far the most successful method & was inherited, like the tendency of a bull-dog to pin the nose of a bull or of a ferret to bite the Cerebellum. It would not be a very great step in advance to prick the ganglion of its prey only slightly, & thus to give its larvæ fresh meat instead of old dried meat. Though Fabre insists so strongly on the unvarying character of instinct, yet it is shown that there is some variability, as at p. 176, 177.⁹

I fear that I shall have utterly wearied you with my scribbling & bad hand-writing—

My dear Romanes | Yours very sincerely | Ch. Darwin