Schleiden

SCHLEIDEN (Matthias Jakob Schleiden; 1804-1881). Initially received a legal education. From 1831, he studied natural sciences and medicine. From 1840 to 1862, he was a professor of botany in Jena, and in 1863 for a short time, a professor of anthropology and plant chemistry in Dorpat (Yuryev). In 1842-44, he published his fundamental book, later reprinted several times, "Grundzüge der Botanik" (Vols. I-II, Leipzig), which marks the date of the appearance of a new scientific botany. The main requirements of S. for this science were its liberation from theology, the dominance of the inductive method in research, and the careful study of the developmental history of plants. Together with Nägeli, he published the leading botanical journal Zeitschrift für wissenschaftliche Botanik. He is best known as the creator (partially together with Schwann) of the cell theory, first clearly formulated for plants in 1838 in his article "Beiträge zur Phytogenesis", published in Müller's Archiv. Having raised the question of the origin of cells, S. placed the recently discovered nucleus in the first place and assumed that around it as some organizing center, a new cell arises from a primary indifferent embryonic mass. Despite the complete error of this concept, the views of S. had exceptional significance, and he rightfully bears the name of the creator of the cell theory, although his concept of the unit of the organism as a cell in the narrow sense of this word, i.e., as an area necessarily bounded by a dense membrane (to which decisive importance is attributed), with a nucleus inside, underwent a fundamental revision in the sense of highlighting the concept of the cell body-protoplasm. S. is the author of "Handbuch der medizinisch-pharmazeutischen Botanik" (Vols. I-II, Leipzig, 1852-57) and a number of other geographical and historical works (in particular on the history of Jews), as well as poems (2 collections published). A monument to S. was erected in Jena (1904).