云南高黎贡山西坡玉山竹属二新种简

发表了云南高黎贡山西坡玉山竹属二新种：大玉山竹（Yushania gigantea Yi et L.Yang）和片马玉山竹（Yushania pianmaensis Yi et L.Yang）。大玉山竹近似西藏玉山竹（Y.xizangensis Yi），不同在于秆柄粗壮，直径7~12 mm，节间长达2.5 cm；秆较高大，高6~7 m，节间分枝一侧基部扁平或具短纵沟槽；小枝具（5）6（7）叶；叶鞘较长，长（2.5）3.2~4.8 cm；叶柄无毛；叶片较大，长（3.5）10~ 18（20） cm，宽(4.5)8~13（18） mm，易于区别。片马玉山竹相似大玉山竹（Y.gigantea Yi et L.Yang），但本种秆较矮小，高2.5~4 m，直径1~1.8（2.5） cm；枝条较多而细，在秆上每节12~30枚，直径1~1.5（2） mm；箨鞘背面无毛，箨片较小，长1.5~3.5 cm，宽1~2.5 mm；小枝具叶较少，为（3）4~5枚；叶片较小，长达12.5 cm，宽达8 mm。

Two New Species of Yushania Keng f.(Poaceae) from Western Slope of Gaoligongshan,Yunnan,China

This paper issued two new species of Yushania Keng f. from Western Slope of Gaoligongshan, Yunnan. Y.gigantea Yi et L. Yang is similar to Y.xizangensis Yi, but collar of this species is wide, 7~12 mm in diam., internode to 2.5 cm long; bigger culms, 6~7 m tall, internodes complanate or short longitudinal ditch on base a side of ramification, leaves (5) 6 (7) per ultimate, sheath (2.5) 3.2~4.8 cm long;,petiobles glabrous,blade biger, (3.5)10~18(20) cm×(0.45)8~1.3(1.8) cm. Y.pianmaensis Yi et L. Yang differs from Y.gigantea Yi et L. Yang by its shorter and smaller culms, 2.5~4 m high, 1~1.8（2.5） cm in diam.; more branches in per nodes, 12~30 per node, more slender, 1~1.5(2) mm diam. , culm sheaths glabrous, smaller blade, 1.5~3.5 cm long, 1~2.5 mm wide; A fewer leaves, (3)4~5 per ultimate branch, smaller blade, 12.5×0.8 cm.