DEAR PROFESSOR HUXLEY,--A short time before Mr. Darwin's death, I had a conversation with, him concerning the observations which had been made by Mr. Murray upon coral-reefs, and the speculations which had been founded upon those observations. I found that Mr. Darwin had very carefully considered the whole subject, and that while, on the one hand, he did not regard the actual facts recorded by Mr. Murray as absolutely inconsistent with his own theory of subsidence, on the other hand, he did not believe that they necessitated or supported the hypothesis advanced by Mr. Murray. Mr. Darwin's attitude, as I understood it, towards Mr. Murray's objections to the theory of subsidence was exactly similar to that maintained by him with respect to Professor Semper's criticism, which was of a very similar character; and his position with regard to the whole question was almost identical with that subsequently so clearly defined by Professor Dana in his well-known articles published in the "American Journal of Science" for 1885. It is difficult to imagine how any one, acquainted with the scientific literature of the last seven years, could possibly suggest that Mr. Murray's memoir published in 1880 had failed to secure a due amount of attention. Mr. Murray, by his position in the "Challenger" office, occupied an exceptionally favourable position for making his views widely known; and he had, moreover, the singular good fortune to secure from the first the advocacy of so able and brilliant a writer as Professor Archibald Geikie, who in a special discourse and in several treatises on geology and physical geology very strongly supported the new theory. It would be an endless task to attempt to give references to the various scientific journals which have discussed the subject, but I may add that every treatise on geology which has been published, since Mr. Murray's views were made known, has dealt with his observations at considerable length. This is true of Professor A.H. Green's "Physical Geology," published in 1882; of Professor Prestwich's "Geology, Chemical and Physical"; and of Professor James Geikie's "Outlines of Geology," published in 1886. Similar prominence is given to the subject in De Lapparent's "Traité de Géologie," published in 1885, and in Credner's "Elemente der Geologie," which has appeared during the present year. If this be a "conspiracy of silence," where, alas! can the geological speculator seek for fame?--Yours very truly, JOHN W. JUDD. _October_ 10, 1887. FOOTNOTES: [28] _The Advance of Science_. Three sermons preached in Manchester Cathedral on Sunday, September 4, 1887, during the meeting of the British Association for the Advancement of Science, by the Bishop of Carlisle, the Bishop of Bedford, and the Bishop of Manchester. [29] Reprinted in Vol. IV. of this collection. [30] _American Journal of Science_, 1885, p. 190.