Prussian physician and botanist; director of the Botanical Gardens of St Petersburg. Siegesbeck gained notoriety as a critic of Linnaeus.

Johann Georg Siegesbeck was born at Seehausen, near Magdeburg, and took his doctor of medicine degree in Wittenberg in 1716. After this he practised as a physician in his hometown, then at Helmstedt from 1730-1735, meanwhile studying botany under Lorenz Heister. Botany eventually took over from medicine for Siegesbeck and he was appointed a demonstrator at the Botanical Garden of St Petersburg in 1735. He went on to take up the post of Professor of Botany at the Russian Academy of Sciences and director of the Botanical Gardens, where he remained until 1747. Afterwards he returned to Seehausen, again working as a physician, until his death in 1755.

Initially a friend of Linnaeus, Siegesbeck wrote pleasant letters to the Swede while he was based at the Hartekamp with George Clifford, between 1735 and 1737. (Siegesbeck also sent Russian plants to Clifford for his collection.) In particular he informed Linnaeus that he was beginning a botanical correspondence to collect exotic plants for the medical gardens at St Petersburg. He later became a fierce critic of the Swedish botanist's ideas, though, the basis of his gripe being moral rather than scientific. In his refutation of Linnaeus' sexual system, Epicrisis in clar. Linnaei nuperrime evulgatum systema plantarum sexuale, et huic superstructam methodum botanicam, Siegesbeck mockingly asked whether God would allow 20 men or more (i.e. the stamens) to have one wife in common (i.e. the pistil), for example.

In retaliation, Linnaeus named an insignificant weed Siegesbeckia L., which was published in Hortus Cliffortianus (1737). He was right to be wary of Siegesbeck's criticism, for when Linnaeus returned to Sweden he found he was a laughing stock thanks to the latter. A successful defence was made on his behalf by Linnaeus' friend Johan Browallius (1707-1775) but the animosity between Linnaeus and Siegesbeck endured. The spat continued in publications and in an episode whereby a packet of Siegesbeckia orientalis seeds was relabelled Cuculus ingratus ('ungrateful cuckoo') by Linnaeus and accidentally sent to Siegesbeck, who grew the seeds, only to find their true identity. After this, Siegesbeck put an end to exchange with Uppsala, greatly impeding Linnaeus' work on the Siberian flora.

Sources:
H.C. Kuhn & E. Kesser, "The Polemics between Carl Linnaeus and Johann Georg Siegesbeck":
www.scricciolo.com/linnaeus_polemic.htm, accessed 1 December 2011
M. Rowell, 1980, "Linnaeus and Botanists in Eighteenth-Century Russia", Taxon, 29(1): 19-20
L. Stieda, 1892, "Siegesbeck, Johann Georg", Allgemeine Deutsche Biographie, 24: 199.