Summary. Following fieldwork in Yunnan and the recent introduction of several Sino-Himalayan bamboos, an additional 10 species are now considered to belong in the genus Borinda Stapleton. B. albocerea, B. edulis, B. frigidorum, B. fungosa, B. hsuehana, B. lushuiensis, B. papyrifera and B. perlonga from Yunnan, and B. fansipanensis from N Vietnam, were all originally described in Fargesia Franch., while B. schmidiana from S Vietnam was originally described in Arundinaria Michx. This extends the distribution of Borinda along a continuous belt of mountain ranges from western Nepal to southern Vietnam, and brings the total number of species in the genus to 18. The genus Borinda was created for clump-forming temperate Sino-Himalayan bamboos that could not be accommodated in Fargesia because of their more open synflorescences, with paniculate rather than racemose branching, and a cylindrical rather than unilateral arrangement of paraclades. Eight species from Nepal, Bhutan and Tibet were initially placed in the genus (Stapleton 1994). Field study in Yunnan, examination of herbarium material, and observation of introduced plants has now shown that the distribution of the genus is substantially wider, extending along a continuous chain of mountain ranges from Annapurna in West Nepal, to Lang Bian Mountain (Lam Vien) in southern Vietnam, only 150 miles from Ho Chi Minh City (Saigon). An additional ten species are now considered to belong in Borinda, increasing the number of species in the genus to eighteen. Borinda was named in honour of Dr Norman Bor, Head of the Grasses Section and Deputy Director of the Royal Botanic Gardens, Kew, in recognition of his life's work, most of which was devoted to the forests and grasses of N E India (Hubbard 1975). B. macclureana (Bor) Stapleton is representative of the type of the genus. Speciation and endemism in these temperate bamboos is apparently high. Valleys from the high Tibetan plateau, and well-separated peaks arising from the lower plateau of Yunnan and N Vietnam are all relatively isolated. Many of these montane habitats are severely threatened by deforestation, over-grazing or mining, and survival of these bamboos in degraded sites is not assured, especially after flowering. Nevertheless several Borinda species presently provide non-timber forest products of considerable economic importance, and their culms are systematically extracted from remaining areas of natural forest or cultivated clumps. The majority of the species in this genus were described for the first time in the 1980s, nearly all from sterile material, and often from a very limited number of collections. Considerable work remains to refine species delimitation, and to relate