Abstract: Wei-Ling-Xian is a Chinese traditional drug widely used for the treatment of rheumatism.A recent survey of the drug market revealed, however, that the drug under the general name "Wei-Lin-gXian" involves many plants of different origins. They belong to 4 families, 5 genera and at least 14 species (cf. Tab. 1), but ethnopharmacologically. they have been shown to possess similar actions.This paper reports those drugs derived from the Clematis genus. Comparing the morphological and histological characters of 9 species of Clematis, viz., C. chinensis, C. unicinata, C. finetiana, C. meyeniana, C. hexapetala, C. manshurica, C. paniculata, C. florida and C, lasiandra, the result showed that they can be distinguished more obviously in histology.By means of TLC and a quantitative spectrophotometric method, all these 9 species were shown tocontain anemonine, amounting to 0.314～4.376% depending on the species of the plants, and the condition of the sample and supposed to contain oleanolic acid after hydrolysis of the saponin present, as shown by direct comparison with the authentic sample.In addition, two analytical keys for the drugs and original plants, respectively, together with 6 figures and 2 plats are here presented.