摘 要 ：利用光学显微镜观察了飘拂草属12个类群（包括变种和变型）的叶片下表皮微形态。飘拂草属叶下表皮微形态基本特征如下：即长细胞为长筒形、短筒形，少数为近方形或多边形，边缘深波状、浅波状至近平直；无短细胞存在；刺毛仅存在于个别种中；气孔器大多为1～2列，少数2～4列；副卫细胞为圆屋顶形至三角形、圆屋顶形，少数为平行形。根据脉间刺毛的有无，可以分为无刺毛类型和有刺毛类型。根据外部形态和叶下表皮微形态上的区别，矮扁鞘飘拂草，应恢复其种级（Fimbristylis kraussiana Hochst. et Steud.）。矮两歧飘拂草作为变种处理比较好，其新等级种名为：F.dichotoma (L.) Vahl var. depauperata（C. B. Clarke）F. Z. Li et L. N. Liu comb. & stat. nov.
Abstract:The micro-morphology of leaf abaxial epidermis of 12 species (including varieties and forma) of Fimbristylis from shandong were studied under light microscope.The results show that Fimbristylis is highly consistent in the micro-morphological characters, e.g. the shape of long-cells long-tubular or short-tubular, rarely sub-tetragonal or polygonal,the margin of cell wall sinuate, sinuolate to straight; short-cells between the vein absent; prickle hairs only exist in rare species; stomas between the vein mostly 2 columns, rarely 2~4 columns;subsidary cells dome-shaped to triangular,dome-shaped, rarely parallel-sided. The leaf abaxial epidermis can be divided into two types: the prickle hairs exist and absent. According to morphology and micro-morphology of leaf abaxial epidermis, F.complanata (Retz.) Link var. kraussiana C. B. Clarke should be rehabilitated to species rank F.kraussiana Hochst et Steud. and F.dichotoma (L.) Vahl F. depauperat（C. B. Clarke）Ohwi is treated as F.dichotoma (L.) Vahl var. depauperata（C. B. Clarke）F. Z. Li et L. N. Liu comb. & stat. nov.