was bound to say that the resemblance of the jaw to that of the dog is superficial; the number and correspondence and development of teeth being widely different. I think again when speaking of the necessity of altering a number of characters together, he ought to have thought of man having power by selection to modify simultaneously or almost simultaneously many points, as in making a greyhound or racehorse--as enlarged upon in my 'Domestic Animals.' Mivart is savage or contemptuous about my "moral sense," and so probably will you be. I am extremely pleased that he agrees with my position, AS FAR AS ANIMAL NATURE IS CONCERNED, of man in the series; or if anything, thinks I have erred in making him too distinct. Forgive me for scribbling at such length. You have put me quite in good spirits; I did so dread having been unintentionally unfair towards your views. I hope earnestly the second volume will escape as well. I care now very little what others say. As for our not quite agreeing, really in such complex subjects, it is almost impossible for two men who arrive independently at their conclusions to agree fully, it would be unnatural for them to do so. Yours ever, very sincerely, CH. DARWIN. [Professor Haeckel seems to have been one of the first to write to my father about the 'Descent of Man.' I quote from his reply:-- "I must send you a few words to thank you for your interesting, and I may truly say, charming letter. I am delighted that you approve of my book, as far as you have read it. I felt very great difficulty and doubt how often I ought to allude to what you have published; strictly speaking every idea, although occurring independently to me, if published by you previously ought to have appeared as if taken from your works, but this would have made my book very dull reading; and I hoped that a full acknowledgment at the beginning would suffice. (In the introduction to the 'Descent of Man' the author wrote:-- "This last naturalist [Haeckel]... has recently... published his 'Naturliche Schopfungs-geschichte,' in which he fully discusses the genealogy of man. If this work had appeared before my essay had been written, I should probably never have completed it. Almost all the conclusions at which I have arrived, I find confirmed by this naturalist, whose knowledge on many points is much fuller than mine.") I cannot tell you how glad I am to find that I have expressed my high admiration of your labours with sufficient clearness; I am sure that I have not expressed it too strongly."] CHARLES DARWIN TO A.R. WALLACE. Down, March 16, 1871. My dear Wallace,