. . .I hope by this time you have my book. I can the less explain the delay since M. Cuvier, to whom I sent it in the same way, has acknowledged its arrival. I inclose his letter, hoping it will give you pleasure to read what one of the greatest naturalists of the age writes me about it. CUVIER TO LOUIS AGASSIZ. PARIS, AU JARDIN DU ROI, August 3, 1829. . . .You and M. de Martius have done me honor in placing my name at the head of a work so admirable as the one you have just published. The importance and the rarity of the species therein described, as well as the beauty of the figures, will make the work an important one in ichthyology, and nothing could heighten its value more than the accuracy of your descriptions. It will be of the greatest use to me in my History of Fishes. I had already referred to the plates in the second edition of my "Regne Animal." I shall do all in my power to accelerate the sale among amateurs, either by showing it to such as meet at my house or by calling attention to it in scientific journals. I look with great interest for your history of the fishes of the Alps. It cannot but fill a wide gap in that portion of natural history,--above all, in the different divisions of the genus Salmo. The figures of Bloch, those of Meidinger, and those of Marsigli, are quite insufficient. We have the greater part of the species here, so that it will be easy for me to verify the characters; but only an artist, working on the spot, with specimens fresh from the water, can secure the colors. You will, no doubt, have much to add also respecting the development, habits, and use of all these fishes. Perhaps you would do well to limit yourself at first to a monograph of the Salmones. With my thanks for the promised documents, accept the assurance of my warm regard and very sincere attachment. B.G. CUVIER. At last comes the moment, so long anticipated, when the young naturalist's first book is in the hands of his parents. The news of its reception is given in a short and hurried note. FROM HIS FATHER. ORBE, August 31, 1829. I hasten, my dear son, to announce the arrival of your beautiful work, which reached us on Thursday, from Geneva. I have no terms in which to express the pleasure it has given me. In two words, for I have only a moment to myself, I repeat my urgent entreaty that you would hasten your return as much as possible. . .The old father, who waits for you with open heart and arms, sends you the most tender greeting. . . CHAPTER 4. 1829-1830: AGE 22-23. Scientific Meeting at Heidelberg. Visit at Home. Illness and Death of his Grandfather. Return to Munich. Plans for Future Scientific Publications. Takes his Degree of Medicine. Visit to Vienna. Return to Munich. Home Letters. Last Days at Munich. Autobiographical Review of School and University Life. TO HIS PARENTS. HEIDELBERG, September 25, 1829.