What is Walther Flemming?
[[File:Walther flemming.gif|thumb|Walther Flemming]] [[Image:Flemming1882Tafel1Fig14.jpg|thumb|Drawing of a ''Chironomus'' (midge) salivary gland cell published by Walther Flemming in 1882. The nucleus contains polytene [[chromosome]]s like those of ''[[Drosophila]]''.]] '''Walther Flemming''' (21 April 1843 – 4 August 1905) was a [[Germany|German]] [[biologist]] and a founder of [[cytogenetics]]. Making use of [[dye]]s he was able to find a structure which he named [[chromatin]]. He identified that chromatin was correlated to threadlike structures in the [[cell nucleus]]– the [[chromosome]]s (meaning ''coloured body''). [[Edouard Van Beneden]] (1846–1910) had also observed them, independently. Flemming investigated the process of [[cell division]] and the distribution of chromosomes to the daughter nuclei, a process he called [[mitosis]] from the Greek word for thread. However, he did not see the splitting into identical halves, the daughter chromatids. He studied mitosis, both in life and in stained preparations, using as the source of biological material the [[fin]]s and [[gill]]s of [[salamander]]s. These results were published first in 1878 <ref>{{Cite web |url=http://www.schriften.uni-kiel.de/Band%203/Flemming%20(23-27).pdf |title=Flemming, W. Zur Kenntniss der Zelle und ihrer Theilungs-Erscheinungen. In: Schriften des Naturwissenschaftlichen Vereins für Schleswig-Holstein 3 (1878), 23–27. |access-date=2009-11-16 |archive-date=2018-04-10 |archive-url=https://web.archive.org/web/20180410110524/http://www.schriften.uni-kiel.de/Band%203/Flemming%20(23-27).pdf |url-status=dead }}</ref> and in 1882 in the seminal book ''Zellsubstanz, Kern und Zelltheilung'' (1882; Cell substance, nucleus and cell division). On the basis of his discoveries, Flemming surmised for the first time that all cell nuclei came from another predecessor nucleus (he coined the phrase ''omnis nucleus e nucleo'', after [[Rudolf Virchow|Virchow's]] ''omnis cellula e cellula''). Flemming was unaware of [[Gregor Mendel]]'s (1822–1884) work o