Abstract: In order to provide a method of distinguishing the Chinese traditional drug Baixianpi and its substitutes, a comparative study of the macroscopical and microscopical characters of the true Baixianpi, the root-bark of Dictamnus dasycarpus (family Rutaceae), and two substitutes, the root-barks of Cynanchum Chinese (family Asclepiadaceae) and Caragana sinica (family Leguminosae), were undertaken. The results showed that the three kinds of root-barks can be distinguished from each other macroscopically by their shape, colour and texture; and microscopically by their shape of cork cells, the type and distribution of sclerenchyma, the presence or absence of secretory cells, and the type of calcium oxalate crystals.

Key words: Dictamnus dasycarpus, Cynanchum Chinese, Caragana sinica root-bark morphology, Histology