- Pringsheim , Nathanael
- (1823–1894) German botanistPringsheim, who was born at Wziesko (now in Poland), studied medicine at the universities of Breslau and Leipzig. However, his interest turned to natural science when he moved to the University of Berlin; he gained his PhD in 1848 with a thesis on the growth and thickness of plant cell walls. In 1864 he was appointed professor of botany at the University of Jena but resigned the post in 1868 to conduct private research in a laboratory attached to his home in Berlin.Pringsheim was one of the leaders in the botanical revival of the 19th century with his contribution to studies of cell development and life history, particularly in the algae and fungi. He was among the first to demonstrate sexual reproduction in algae and observe alternation of generations between the two sexually differentiated motile zoospores and the resting undifferentiated spore that results from their fusion. He further showed that sexual reproduction involves fusion of material of the two sex cells.From studies (1873) on the complex morphological differentiation in a family of marine algae, the Sphacelariaceae, Pringsheim opposed the Darwinian theory of evolution by natural selection. Like the Swiss botanist, Karl Naegeli, he believed the increase in structural complexity to be a spontaneous morphological phenomenon, conferring no survival value.Pringsheim's studies of the origin of plant cells contributed evidence for the theory that cells are only produced by the division of existing cells. With Julius von Sachs, Pringsheim also described the plastids, organelles unique to plant cells. In later years he concentrated more on physiology than morphology but his contributions to this field were not acknowledged or developed by other workers.He was founder of the Jahrbücher für Wissenschaftliche Botanik(1858; Annals of Scientific Botany) and the German Botanical Society (1882). He wrote memoirs on Vaucheria (1855),Oedogonium and Coleochaete (1856–58), Hydrodictyon (1861), and Pandorina (1869).
Scientists. Academic. 2011.