I finished your Elephant paper last night, and you must let me express my admiration at it. (155/2. "On the American Fossil Elephant of the Regions bordering the Gulf of Mexico (E. Columbi, Falc.), etc." "Nat. Hist. Rev." 1863, page 81. (Cf. Letter to Lyell. "Life and Letters," II., page 389; also "Origin," Edition VI., page 306.) See Letter 143.) All the points strike me as admirably worked out, and very many most interesting. I was particularly struck with your remarks on the character of the ancient Mammalian Fauna of N. America (155/3. Falconer, page 62. This passage is marked in Darwin's copy.); it agrees with all I fancied was the case, namely a temporary irruption of S. American forms into N. America, and conversely, I chuckled a little over the specimen of M. Andium "hesitating" between the two groups. (155/4. In speaking of the characters of Mastodon Andium, Falconer refers to a former paper by himself ("Quart. Journ. Geol. Soc." Volume XIII. 1857, page 313), in which he called attention "to the exceptional character of certain specimens of M. Andium, as if hesitating between [the groups] Tetralophodon and Trilophodon" (ibid., page 100).) I have been assured by Mr. Wallace that abundant Mastodon remains have been found at Timor, and that is rather close to Australia. I rejoice that you have smashed that case. (155/5. In the paper in the "Nat. Hist. Review" (loc. cit.) Falconer writes: "It seems more probable that some unintentional error has got mixed up with the history of this remarkable fossil; and until further confirmatory evidence is adduced, of an unimpeachable character, faith cannot be reposed in the reality of the asserted Australian Mastodon" (page 101).) It is indeed a grand paper. I will say nothing more about your allusions to me, except that they have pleased me quite as much in print as in MS. You must have worked very hard; the labour must have been extreme, but I do hope that you will have health and strength to go on. You would laugh if you could see how indignant all Owen's mean conduct about E. Columbi made me. (155/6. See Letter 157.) I did not get to sleep till past 3 o'clock. How well you lash him, firmly and severely, with unruffled temper, as if you were performing a simple duty. The case is come to such a pass, that I think every man of science is bound to show his feelings by some overt act, and I shall watch for a fitting opportunity.