"The first course of lectures on zoology I attended was given in Lausanne in 1823. It consisted chiefly of extracts from Cuvier's 'Regne Animal,' and from Lamarck's 'Animaux sans Vertebres.' I now became aware, for the first time, that the learned differ in their classifications. With this discovery, an immense field of study opened before me, and I longed for some knowledge of anatomy, that I might see for myself where the truth was. During two years spent in the Medical School of Zurich, I applied myself exclusively to the study of anatomy, physiology, and zoology, under the guidance of Professors Schinz and Hirzel. My inability to buy books was, perhaps, not so great a misfortune as it seemed to me; at least, it saved me from too great dependence on written authority. I spent all my time in dissecting animals and in studying human anatomy, not forgetting my favorite amusements of fishing and collecting. I was always surrounded with pets, and had at this time some forty birds flying about my study, with no other home than a large pine-tree in the corner. I still remember my grief when a visitor, entering suddenly, caught one of my little favorites between the floor and the door, and he was killed before I could extricate him. Professor Schinz's private collection of birds was my daily resort, and I then described every bird it contained, as I could not afford to buy even a text-book of ornithology. I also copied with my own hand, having no means of purchasing the work, two volumes of Lamarck's 'Animaux sans Vertebres,' and my dear brother copied another half volume for me. I finally learned that the study of the things themselves was far more attractive than the books I so much coveted; and when, at last, large libraries became accessible to me, I usually contented myself with turning over the leaves of the volumes on natural history, looking at the illustrations, and recording the titles of the works, that I might readily consult them for identification of such objects as I should have an opportunity of examining in nature.