toward one end. I have for six months frequented a blacksmith's and carpenter's shop, learning to handle hammer and axe, and I also practice arms, the bayonet and sabre exercise. I am strong and robust, know how to swim, and do not fear forced marches. I have, when botanizing and geologizing, walked my twelve or fifteen leagues a day for eight days in succession, carrying on my back a heavy bag loaded with plants or minerals. In one word, I seem to myself made to be a traveling naturalist. I only need to regulate the impetuosity which carries me away. I beg you, then, to be my guide." The unfinished letter closes abruptly, having neither signature nor address. Perhaps the writer's courage failed him and it never was sent. An old letter (date 1827) from Cuvier to Martius, found among Agassiz's papers of this time, and containing the very notes on the Spix Fishes to which allusion is here made, leaves no doubt, however, that this appeal was intended for the great master who exercised so powerful an influence upon Agassiz throughout his whole life. In the spring of 1829 Agassiz took his diploma in the faculty of philosophy. He did this with no idea of making it a substitute for his medical degree, but partly in deference to Martius, who wished the name of his young colleague to appear on the title-page of the Brazilian Fishes with the dignity of Doctor, and partly because he believed it would strengthen his chance of a future professorship. Of his experience on this occasion he gives some account in the following letter:-- TO HIS BROTHER. MUNICH, May 22, 1829. As it was necessary for me to go through with my examination at once, and as the days for promotion here were already engaged two months in advance, I decided to pass it at Erlangen. That I might not go alone, and also for the pleasure of their company, I persuaded Schimper and Michahelles to do the same. Braun wanted to be of the party, but afterward decided to wait awhile. We made our request to the Faculty in a long Latin letter (because, you know, among savants it is the thing to speak and write the language you know least), requesting permission to pass our examination in writing, and to go to Erlangen only for the colloquium and promotion. They granted our request on condition of our promise (jurisjurandi loco polliciti sumus) to answer the questions propounded without help from any one and without consulting books. Among other things I had to develop a natural system of zoology, to show the relation between human history and natural history, to determine the true basis and limits of the philosophy of nature, etc. As an inaugural dissertation, I presented some general and novel considerations on the formation of the skeleton throughout