A revision of the anatomy of Gunneraceae

New studies on the anatomy of the leaf, stem, stolen and root of 17 taxa of Gunnera have revealed several interesting anatomical features. Scalariform perforation plates occur in most vessel elements of stolons and roots, alt hough simple perforation plates are more frequent in the stems of large lea fed-species. The leaf surface and internal anatomy have not been studied si nce the late 19th and early 20th centuries. In this paper, detailed studies of the leaf include features such as marginal and laminar hydathodes, 'war ts', hair types, and groups of 2-5 palisade-like cells connected to each ot her by short communicating tubes. The anatomy of Gunnera herteri is describ ed in detail for the first lime. Nostoc colonies in the leaf are illustrate d. (C) 2000 Thr Linnean Society of London.