to be primarily confined to Monocotyledons. After the division of the Natural History Department of the British Museum into three sections in 1837, Robert Brown became the first Keeper of the Botanical Department, remaining so until his death. He was succeeded by John Joseph Bennett. He served as President of the Linnean Society from 1849 to 1853. Brown died at 17 Dean Street, Soho Square in London, on 10 June 1858. He was buried in Kensal Green Cemetery in London. Brown's name is commemorated in the Australia herb genus Brunonia as well as numerous Australian species such as Eucalyptus brownii, Banksia brownii and the moss Brown's Tetrodontium Moss (Tetrodontium brownianum), a species which he discovered growing at Roslin near Edinburgh whilst still a student. The plant can still be found at the site of its discovery. Passing through the suburb of Kingston, south of Hobart, Tasmania, formerly Van Diemen's Land, is Brown's River, named in his honor, upon the banks of which, he collected botanical samples. In South Australia, Mount Brown and Point Brown (near Smoky Bay) were named for him by Flinders during the Investigator expedition. Mount Brown in British Columbia, Canada was named for him by David Douglas. In 1938 the London County Council commemorated Brown, as well as botanists Joseph Banks and David Don, and meetings of the Linnean Society, with a rectangular stone plaque at 32 Soho Square. A small New Zealand tree Pisonia brunoniana was named in recognition of him, and Cape Brown (Greenland) was named by William Scoresby (1789–1857) in 1822 in his honour. Brownian motion In 1827, while examining grains of pollen of the plant Clarkia pulchella suspended in water under a microscope, Brown observed minute particles, now known to be amyloplasts (starch organelles) and spherosomes (lipid organelles), ejected from the pollen grains, executing a continuous jittery motion. He then observed the same motion in particles of inorganic matter, enabling him to rule out the hypothesis that the effect was life-related. Although Brown did not provide a theory to explain the motion the phenomenon is now known as Brownian motion. In recent years controversy arose over whether Brown's microscopes were sufficient to reveal phenomena of this order. Brown's discoveries were denied in a brief paper in 1991. Shortly thereafter, in an illustrated presentation, British microscopist Brian J. Ford presented to Inter Micro 1991 in Chicago a reprise of the demonstration using Brown's original