. . .I write in all haste to ask for any address to which I can safely forward my report on the Sheppy fishes, so that they may arrive without fail in time for the meeting at York. Since my last letter I have made progress in this kind of research. I have sacrificed all my duplicates of our present fishes to furnish skeletons. I have prepared more than a hundred since I last wrote you, and I can now determine the family, and even the genus, simply by seeing the skull. There remains nothing impossible now in the determination of fishes, and if I can obtain certain exotic genera, which I have not as yet, I can make an osteology of fishes as complete as that which we possess for the other classes of vertebrates. Every family has its special type of skull. All this is extremely interesting. I have already corrected a mass of inaccurate identifications established upon external characters; and as for fossils, I have recognized and characterized seventeen new genera among the less perfect undetermined specimens you have sent me. Several families appear now for the first time among the fossils. I have been able to determine to what family all the doubtful genera belong; indeed Sheppy will prove as rich in species as Mont Bolca. When you see your specimens again you will hardly recognize them, they are so changed; I have chiseled and cleaned them, until they are almost like anatomical preparations. Try to procure as many more specimens as possible and send them to me. I cannot stir from Neuchatel, now that I am so fully in the spirit of work, and besides it would be a useless expense. . .You will receive with my report the three numbers which complete my monograph of the Fishes of the Old Red. I feel sure, in advance, that you will be satisfied with them. . . SIR PHILIP EGERTON TO LOUIS AGASSIZ. TOLLY HOUSE, ALNESS, ROSS-SHIRE. September 15, 1844.