| Johan Lange | |
| Birth Date: | 20 March 1818 |
| Birth Place: | Ødstedgård near Vejle, Denmark |
| Nationality: | Danish |
| Death Place: | Copenhagen |
| Field: | botany |
| Alma Mater: | University of Copenhagen |
| Known For: | Flora Danica, Prodromus Florae Hispanicae and four editions a Flora of Denmark |
Johan Martin Christian Lange (20 March 1818 - 3 April 1898) was a prominent Danish botanist.[1]
He held the post of Librarian at the Botanical library of the University of Copenhagen from 1851 to 1858. He was Director of the Botanical Garden there from 1856 to 1876, the Reader of botany at the Danish Technical University from 1857 to 1862, and Reader of Botany at the Royal Veterinary and Agricultural University from 1858 to 1893, achieving full professor standing in 1892. He began editing the Flora Danica in 1858, and was its last editor. Together with Japetus Steenstrup, Johan Lange was the publisher of Flora Danica fasc. 44 (1858). Thereafter, he edited alone fasc. 45-51 (1861–83) and Supplement vols 2-3 (1865–74), in total 600 plates. After having finished the publication of Flora Danica, he issued Nomenclator Floræ Danicæ in 1887 - a volume indexing all planches in Flora Danica alphabetically, systematically and chronologically. Lange edited the exsiccata Plantae Europae australis 1851-52.[2]
He travelled throughout Europe, completing extensive studies on the flora of Denmark, Greenland and other European countries, especially Spain. (Willkomm & Lange, Prodromus Florae Hispanicae, 1861–80).
He expanded on the classification developed by Linnaeus, writing Plantenavne og navngivningsregler (Plant-names and rules for name-giving) which was influential in developing the Code of Botanical Nomenclature, the system in use today.
Charles Darwin borrowed a book written by Lange, which he failed to return in a timely manner as mentioned by Darwin in his correspondence. https://web.archive.org/web/20060106141907/http://darwin.lib.cam.ac.uk/perl/nav?pclass=letter&pkey=2246
He is honoured in the naming of a fungal genus in 1891, Willkommlangea (jointly with Heinrich Moritz Willkomm (1821-1895), who was a German academic and botanist).[3]