I thank you much for your letter. I had got to take pleasure in thinking how I could best snub my reviewers; but I was determined, in any case, to follow your advice, and, before I had got to the end of your letter, I was convinced of the wisdom of your advice. ("I get on slowly with my new edition. I find that your advice was EXCELLENT. I can answer all reviews, without any direct notice of them, by a little enlargement here and there, with here and there a new paragraph. Bronn alone I shall treat with the respect of giving his objections with his name. I think I shall improve my book a good deal, and add only some twenty pages."--From a letter to Lyell, December 4th, 1860.) What an advantage it is to me to have such friends as you. I shall follow every hint in your letter exactly. I have just heard from Murray; he says he sold 700 copies at his sale, and that he has not half the number to supply; so that I must begin at once (On the third edition of the 'Origin of Species,' published in April 1861.)... P.S.--I must tell you one little fact which has pleased me. You may remember that I adduce electrical organs of fish as one of the greatest difficulties which have occurred to me, and -- notices the passage in a singularly disingenuous spirit. Well, McDonnell, of Dublin (a first-rate man), writes to me that he felt the difficulty of the whole case as overwhelming against me. Not only are the fishes which have electric organs very remote in scale, but the organ is near the head in some, and near the tail in others, and supplied by wholly different nerves. It seems impossible that there could be any transition. Some friend, who is much opposed to me, seems to have crowed over McDonnell, who reports that he said to himself, that if Darwin is right, there must be homologous organs both near the head and tail in other non-electric fish. He set to work, and, by Jove, he has found them! ('On an organ in the Skate, which appears to be the homologue of the electrical organ of the Torpedo,' by R. McDonnell, 'Nat. Hist. Review,' 1861, page 57.) so that some of the difficulty is removed; and is it not satisfactory that my hypothetical notions should have led to pretty discoveries? McDonnell seems very cautious; he says, years must pass before he will venture to call himself a believer in my doctrine, but that on the subjects which he knows well, viz., Morphology and Embryology, my views accord well, and throw light on the whole subject. CHARLES DARWIN TO ASA GRAY. Down, November 26th, 1860. My dear Gray,