Two New Species of Yushania Keng f.(Poaceae) from Northwestern Yunnan in China

In this paper two new species of Yushania Keng f.are reported from Northwestern Yunnan.Yushnia habaensis Yi et L.Yang is similar to Y.bojieana Yi,but taller culms,4~7 m high,1.5~2 (2.5) cm diam.,internodes complanate or short longitudinal ditch on base a side of ramification,obviously longitudinal bridles,solid or subsolid,spongioplasm medullary and rigidity by drying;culm-sheaths culm sheath as long as internodes (length over 1/3 of internode),a few leaves,2~4 per ultimate branch,narrower blade,5~6.5 (10) mm broad,secondary veins 2~3 paired.Yushania gongshanensis Yi et L.Yang seperates from Y.flexa Yi by rhizome neck of thicker,to 2 cm diam,internodes to 2.5 (3) cm long;shorter internodes of culms,20~22 (26) cm long,hollow,longer than internodes,back surface sparse tuberculate setose;shorter leaf-sheath,(1.8) 2.2~3.5 cm,narrower blades,(5) 6.5~10 mm wide.