Karl Wilhelm Von Nägeli

Born Mar. 27, 1817, in Kilchberg, near Zürich; died May 10, 1891, in Munich. German botanist. Nägeli was a privatdocent in Zü rich from 1842 to 1848. He was a professor at the universities of Freiburg (1848–55), Zü rich (1855–58), and Munich (1858–91). His principal works were on the cytology, anatomy, physiology, and taxonomy of plants. Nägeli observed the division of the cell nucleus and introduced the concepts of stable and formative tissues. He studied the development and growth of tissues and the structure and development of conducting bundles. He also discovered spermatozoids in ferns. Nägeli was one of the first to use mathematics in botany. He proposed a speculative theory of heredity and evolution.