The morphology and distribution of leaf trichomes of Isodon rubescens were studied using light microscopy. (l)Three morphologically distinct types of trichomes were observed on I. Rubescens leaf surfaces: non-glandular, peltate and capitate glandular. The glandular and non-glandular trichomes were present on both the adaxial and abaxial surfaces. Peltate and capitate glandular trichomes comprised one basal cell,one or two stalk cells and one head. The head of mature peltate glandular trichomes generally consisted of four secretory cells while that of capitate glandular hairs was composed of two cells. (2)Histochemical results indicate existence of flavnoids in both peltate and capitate glandular trichomes. In addition, terpe-noids,including monoterpenes, sesquiterpenes etc. , exist in peltate glandular trichomes. Peltate glandular trichomes are probably only site of oridonin accumulation,however,this need direct proof to clarify. High density of peltate trichomes might be considered as an important selection character for the screening of I. Rubescens with rich content of oridonin.%利用光学显微镜对药用植物冬凌草地上部分腺毛的形态、分布和组织化学进行了研究.结果表明:(1)冬凌草的叶表皮有3种形态显著不同的毛,即非腺毛、盾状腺毛和头状腺毛；盾状腺毛和头状腺毛均具1个基细胞、1个柄细胞和头部；成熟的盾状腺毛的头部一般由4个分泌细胞组成,而头状腺毛头部由2个分泌细胞组成.(2)组织化学鉴定结果显示:2种腺毛中均含有黄酮类成分,盾状腺毛中还含有单萜、倍半萜等萜类成分；冬凌草甲素可能只存在于盾状腺毛中,但需要更直接的证据证明.研究认为,高密度的盾状腺毛可以作为筛选冬凌草高甲素含量品种的一项重要依据.
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