Braun, Alexander

Born May 10, 1805, in Regensburg; died Mar. 29, 1877, in Berlin. German botanist.

Braun was a professor at the Polytechnic School in Karlsruhe (1833), professor and director of the botanical garden at the University of Freiburg (1846), professor at the University of Berlin, and director of the botanical garden in Berlin (1851). He studied the structure, development, and taxonomy of freshwater green algae, ferns, and sago palms and investigated parthenogenesis and polyembryony in plants, phenomena of symmetry, and other phenomena. Some of his studies contributed to the creation of the cell theory. The natural system of plants developed by Braun served as a base for the later systems of the German botanists A. Eichler and A. Engler. Braun was a proponent of idealistic natural philosophy. According to Braun, the original cause of all changes in organisms is the “spirit, ” which determines a single plan for the structure of all organisms and their internal striving for perfection.