The Grasses (Poaceae): Robert Brown and now

he described a number of new grass genera and species and arranged the genera primarily according to floret number and floral sexuality. Implicit in his circumscription of the family was the recognition of the unique nature of the caryopsis and the specialised grass embryo. In the 1814 Botany of Terra Australis, Brown discussed the morphology of grasses and revised his general classification of the family. Brown divided the family into two ‘tribes ’ (what we would today call subfamilies), the Paniceae and Poaceae, and he explicitly noted the trends toward basal reduction in the spikelets of Paniceae and apical reduction in the Poaceae. He described grass spikelets in detail and drew the general conclusions that these were branched structures, and that the lodicules represented perianth parts. Brown also noted that the Paniceae were more diverse in tropical latitudes, and the Poaceae in temperate latitudes. Brown’s basic classification persisted without radical modification well into the 20th century. Recent phylogenetic analyses of the grass family demonstrate the paraphyly of Brown’s Poaceae, which actually comprises 11 subfamilies, but his Paniceae is retained to a large extent in the modern Panicoideae