. . .After my long fast from news of you, your letter made me very happy. I was dull besides, and needed something to cheer me. . . Since my talk about natural history does not bore you, I want to tell you various other things about it, and also to ask you to do me a favor. I have stuffed a superb otter lately; next week I shall receive a beaver, and I have exchanged all my little toads from Neuchatel for reptiles from Brazil and Java. One of our professors here, who is publishing a natural history of reptiles, will introduce in his work my description of that species, and my observations upon it. He has already had lithographed those drawings of eggs that Cecile made for me, as well as the colored drawings made for me by Braun's sister when I was at Carlsruhe. My collection of fishes is also much increased, but I have no duplicates left of the species I brought with me. I have exchanged them all. I should therefore be greatly obliged if you would get me some more of the same. I will tell you what kinds I want, and how you are to forward them. I have still at Cudrefin several jars of thick green glass. When you go there take them away with you, fill them with alcohol, and put into them as many of these fishes as you can find for me. Put something between every two specimens, to prevent them from rubbing against each other; pack them in a little box wrapped in hay, and send them either by a good opportunity or in the least expensive way. The kinds I want are [here follows the list]. . .It will interest you to know that I am working with a young Dr. Born upon an anatomy and natural history of the fresh-water fishes of Europe. We have already gathered a great deal of material, and I think by the spring, or in the course of the summer, we shall be able to publish the first number. This will bring in a little ready money for a short journey in the vacation. I earnestly advise you to while away your leisure hours with study. Read much, but only good and useful books. I promised to send you something; do not think, because I have not done so yet, that I have forgotten it. On the contrary, the difficulty of choosing is the cause of the delay; but I will make farther inquiry as to what will suit you best and you shall have my list. Meantime remember to read Say, and if you have not already begun it, do not put it off. Remember that statistical and political knowledge alone distinguishes the true merchant from the mere tradesman, and guides him in his undertakings. . .A merchant familiar with the products of a country, its resources, its commercial and political relations with other countries, is much less likely to enter into speculations based on false ideas, and therefore of doubtful issue. Write me about what you are reading and about your plans and projects, for I can hardly believe that any one could exist without forming them: I, at least, could not.