蘭嶼產無芒鴨嘴草（Ischaemum muticum L.，禾本科） 確認

Confi rmation of Ischaemum muticum L. (Poaceae) in Lanyu

本文描述作者近期於蘭嶼尋獲族群的禾草：無芒鴨嘴草（Ischaemum muticum L.，禾本科），檢視本種以往於臺灣植物誌的相關處理後，確認本種禾草分布於蘭嶼濱海溼地，可依據「葉片基部常心形且具假葉柄、小穗常無芒、外穎卵形且光滑」等特徵與其他同屬植物鑑別，並提供蘭嶼產個體繪製之線描圖與相關照片。

Author described population of Ischaemum muticum L. (Poaceae), which was found recently in Lanyu Island by the author’s series botanical surveys. After examinations of relative treatments of this grass species to the flora of Taiwan in past, the author confirmed its distribution on a coastal wetland in Lanyu. This grass species could be distinguished from other congeneric species based on: cordate leaf bases with pseudopetioles, awnless spikelets, and glabrous, ovate lower glumes. In addition, line-drawing and photos based on Lanyu’s materials were offered, too.