Johann Hedwig

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Johann Hedwig

Johann Hedwig , also (Latinized) Ioannis Hedwig and Johannes Hedwig (born December 8, 1730 in Kronstadt , Transylvania , † February 18, 1799 in Leipzig ) was a Saxon-Transylvanian , German medic, doctor and botanist . He is considered the founder of modern bryology . Its official botanical author's abbreviation is " Hedw. ".

Live and act

Hedwig was born in 1730 as the son of Jakob Hedwig and Agnes Galles in Kronstadt , Transylvania , where he attended elementary school and from 1744 the upper secondary school of the Honterus School. He spent after his father's death, most of his life in Leipzig, where, after studying in Vienna and visiting high schools in Bratislava and Zittau from 1751 at the University of Leipzig studied medicine, famulus by Professor Bose and Ludwig was 1759 PhD. The successful completion of his medical studies almost failed due to a lack of financial means when a lucky coincidence came to his aid. Josef Trausch (Writer's Lexicon of the Transylvanian Germans, Vol. I, pp. 84 and 85) reports:

“Then it happened that one day in this embarrassment he heard a violent argument in a street in Leipzig and heard a loud voice from the third floor above him with the words: 'I may not have the money like that either, and it belongs for whoever it will fall to, whereupon a filled purse fell from the window of the house at Hedwig's feet. Hedwig picked up the purse, carried it into the room of the house from which it had been thrown and, to his great pleasure, learned that he had heard correctly and that he had to remain in the fair possession of the purse. "

With this amount of money that fell “from heaven” to him, and with the help of the “Walther” scholarship that his patron Bose had given him, Hedwig was able to continue and successfully complete his studies.

Since he was not allowed to practice in Transylvania after graduating from Leipzig, he worked as a general practitioner in Chemnitz , where he also carried out botanical research. In 1781 he moved back to Leipzig , where he worked as a doctor at the city hospital from 1783 or 1784. In 1786 he became associate professor for medicine , in 1789 full professor for botany and director of the botanical garden of the University of Leipzig. In 1792 he was elected a member of the Leopoldina .

In his spare time he explored the botanical surroundings of Chemnitz. Since he had soon determined the phanerogams occurring there , he turned to the rich moss flora of the city. He was the first botanist to use the microscope to study a certain group of plants, here the moss . Among other things, he had contact with Johann Christian von Schreber , who was professor of botany at the University of Erlangen , and who even gave Hedwig, who was initially an amateur botanist, a microscope. He had a Rheinthalersches microscope with a mere 50x linear magnification. Later he also used 170 to 290 times magnifications.

Gymnostomum japonicum from Species Muscorum Frondosorum

In his moss investigations, Hedwig was also under Linnaeus' powerful influence in so far as he tried to prove that the mosses did not lack the two kinds of genitals on which Linnaeus had based his system of plants. Although Hedwig carried out the investigations of the mosses as a "side work", he proceeded precisely and conscientiously. Hedwig did not publish too hastily, because although he had made his fundamental discovery in 1774, he checked his observations for several years and did not publish a preliminary report of his observations "of the true genitals of mosses and their reproduction" in the "Collections for Physics and Natural History" in 1779 through seeds ”. Hedwig's discoveries were initially met with opposition and envy in science. But to the extent that his opponents and envious people fell silent, so did his followers and admirers.

Erhart named a genus of moss Hedwigia during Hedwig's lifetime . Founded in 1852 by Dr. Rabenhorst founded journal for cryptography and phytopathology also carried the name Hedwigia . This magazine is carried on under the name Nova Hedwigia in our time . From 1786 onwards Hedwig worked at the University of Leipzig as an associate professor for botany and from 1789 full professor of the Botanical Garden , he was considered a skilled microscopist and a good draftsman. His herbarium , admired by Goethe in 1797 , was auctioned in 1810, but was largely acquired by the Geneva Botanical Garden , where the collection is still located today.

Hedwig's greatest achievement is the discovery of the antheridia and archegonia of the mosses, which he correctly interpreted as reproductive organs. (However, this interpretation had not yet become generally accepted in 1818.) Hedwig dealt with the systematics of mosses, but also examined fungi, lichens, ferns and higher plants.

Hedwig was convinced that there had to be sexual reproduction with the corresponding organs also with mushrooms. In his search for sexual structures, he discovered the regular eight-pore form of various asci, which led to him naming a genus Octospora . The term spore as an alternative to the term seed of flowering plants goes back to Hedwig as well as the term sporangium .

Hedwig's main works, Fundamentum historiae naturalis muscorum (1792), in which he portrayed the reproduction of mosses, and Species Muscorum , which was only published posthumously in 1801 by Christian Friedrich Schwägrichen and is considered the beginning of the moss nomenclature, were decisive for understanding mosses and their up to then often unexplained life cycle.

He had a brother named Jakob and was the father of 15 children, including the botanist Roman Adolph Hedwig (1772–1806), who followed in his footsteps professionally and who also became a professor of botany shortly after Hedwig's death (from “typhus”).

In recognition of Hedwig's achievements, the "International Association of Bryologists (IAB)" awards the Hedwig Medal to scientists for extraordinary contributions in the field of bryology.

Fonts (selection)

  • Fundamentum historiae naturalis muscorum frondosorum. 2 volumes. Leipzig 1782.
  • Theoria generationis et fructificationis plantarum cryptogamarum. St. Petersburg 1784; 2nd edition 1797.
  • Descriptio et adumbratio microscopico-analytica muscorum frondosorum nec non aliorum vegetantium e classe cryptogamica Linnaei novorum dubiisque vexatorum. 4 volumes. Leipzig 1787–1797.
  • Collection of his scattered treatises and observations on botanical-economic subjects. 2 volumes. Leipzig 1793–1797.
  • Filicum genera et species. 4 fasc. Leipzig 1799-1803.
  • Species muscorum frondosorum. Edited by F. Schwägrichen. 1 volume u. 4 supplements. Leipzig 1801-1842.

literature

Web links

Individual evidence

  1. ^ Hermann A. Hienz: Writer's Lexicon of the Transylvanian Germans. VII: H – J , Böhlau, 2000, ISBN 3-412-12599-7 .
  2. ^ Ernst Wagner, Heinz Heltmann: Scientific research on Transylvania. Volume 2, Böhlau, 1984, p. 6.


personal data
SURNAME Hedwig, Johann
ALTERNATIVE NAMES Hedwig, Johanness
BRIEF DESCRIPTION German botanist and doctor
DATE OF BIRTH December 8, 1730
PLACE OF BIRTH Kronstadt , Transylvania
DATE OF DEATH February 18, 1799
Place of death Leipzig