have played an extremely small part in producing all the numberless and beautiful adaptations in every living creature. With respect to a person's belief, what does rather surprise me is that any one (like Carpenter) should be willing TO GO SO VERY FAR as to believe that all birds may have descended from one parent, and not go a little farther and include all the members of the same great division; for on such a scale of belief, all the facts in Morphology and in Embryology (the most important in my opinion of all subjects) become mere Divine mockeries... I cannot express how profoundly glad I am that some day you will publish your theoretical view on the modification and endurance of Brachiopodous species; I am sure it will be a most valuable contribution to knowledge. Pray forgive this very egotistical letter, but you yourself are partly to blame for having pleased me so much. I have told Murray to send a copy of my new edition to you, and have written your name. With cordial thanks, pray believe me, my dear Sir, Yours very sincerely, CH. DARWIN. [In Mr. Davidson's Monograph on British Brachiopoda, published shortly afterwards by the Palaeontographical Society, results such as my father anticipated were to some extent obtained. "No less than fifteen commonly received species are demonstrated by Mr. Davidson by the aid of a long series of transitional forms to appertain to... one type." "Lyell, 'Antiquity of Man,' first edition, page 428.) In the autumn of 1860, and the early part of 1861, my father had a good deal of correspondence with Professor Asa Gray on a subject to which reference has already been made--the publication in the form of a pamphlet, of Professor Gray's three articles in the July, August, and October numbers of the 'Atlantic Monthly,' 1860. The pamphlet was published by Messrs. Trubner, with reference to whom my father wrote, "Messrs. Trubner have been most liberal and kind, and say they shall make no charge for all their trouble. I have settled about a few advertisements, and they will gratuitously insert one in their own periodicals."