born Feb. 16, 1848, Haarlem, Neth.
died May 21, 1935, near Amsterdam
Dutch botanist and geneticist.
He taught at the University of Amsterdam (1878–1918), where he introduced the experimental study of organic evolution. His rediscovery in 1900 (simultaneously with Erich Tschermak von Seysenegg ) of Gregor Mendel 's principles of heredity and his own theory of biological mutation explained concepts about the nature of variation of species that made possible the universal acceptance and active investigation of {{link=Darwin, Charles Robert">Charles Darwin 's theory of organic evolution. De Vries discovered and named the phenomenon known as mutation, and he also contributed to knowledge of the role of osmosis in plant physiology. See also William Bateson .