[164] Owen introduced most of the names of bones now current. [165] _Lectures on Invertebrate Animals_, pp. 374, 379, 1843. CHAPTER IX KARL ERNST VON BAER Von Baer was recognised as the founder of embryology even by his contemporaries. His predecessors, Aristotle,[166] Fabricius,[167] Harvey,[168] Malpighi,[169] Haller,[170] Wolff,[171] had made a beginning with the study of development; von Baer, by the thoroughness of his observation and the strength of his analysis, made embryology a science. It was to one of the German transcendentalists that von Baer owed the impulse to study development. Ignatius Doellinger, Professor in Wuerzburg, induced three of his pupils, Pander, d'Alton and von Baer, to devote themselves to embryological research. The development of animals was at this time little known, in spite of recent work by Meckel (1815 and 1817), Tiedemann (_Anatomie u. Bildungsgeschichte des Gehirns_, 1816), by Oken (_loc. cit., supra_, p. 90), and some others. Pander, with whom apparently Doellinger and d'Alton collaborated, was the first to publish his results;[172] von Baer, who through absence from Wuerzburg had for a time dropped his embryological studies, started to work in 1819, after the publication of Pander's treatise, and produced in 1828 the first volume of his master-work, _Ueber Entwickelungsgeschichte der Thiere. Beobachtung und Reflexion_ (Koenigsberg, 1828). The second volume followed in 1837, but dates really from 1834, and was published in an incomplete form. This second volume is intended as an introduction to embryology for the use of doctors and science students. In it von Baer describes in full detail the development of many vertebrate types--chick, tortoise, snake, lizard, frog, fish, several mammals and man, basing his remarks largely upon his personal observations, but taking account also of all contemporary work. A separate account of the development of a fish (_Cyprinus blicca_) appeared in 1835.[173] We shall concentrate attention on the first volume. This volume contains the first full and adequate account of the development of the chick, followed by a masterly discussion of the laws of development in general. When we consider that von Baer worked chiefly with a simple microscope and dissecting needles, the minuteness and accuracy of his observations are astonishing. He described the main facts respecting the development of all the principal organs, and if, through lack of the proper means of observation, he erred in detail, he made up for it by his masterly understanding and profound analysis of the essential nature of development. His account of the development of the chick is a model of what a scientific memoir ought to be; the series of "Scholia" which follow contain the deductions he made from the data, and, in so far as they are direct generalisations from experience, they are valid for all time.