Abstract: The authors have previously reported the morphology and histology of Huang-Ch'i and Hung-Ch'i.In this paper, the morphological and histological characters of nine adulterants, viz. the roots of Althaea officinalis, Melilotus albus, Medicago sativa, Oxytropis caerulea, Caragara sinica, Glycyrrhiza pallidiflora, Malva rotundifolia, M. verticillata, and Astragalus complanatus are described concisely with illustrations. As a result of this and the previous study the commercial samples except those derived from the genus Astragalus, can be distinguished from each other by their macroscopical and microscopical characters. Therefore, capillary analyses of the alcoholic extracts made from the roots of the Astragalus species (including A. complanatus, which is used as an adulterant in certain district) were carried out and their capillary chromatograms compared. By these means, all the samples can be distinguished according to the following key: 1. Crystals of calcium oxalate present 2. Cluster crystals present 3. Cluster crystals present in the xylem ray; simple pits absent from the walls of xylem ray cells and xylem parenchymatous cells 4. Starch grains elliptical in shape, 6—12—15 μ long and 4—6—8 μ wide; xylem occupies 2/3 of the radius; fibres scanty Radix Altkaeae officinalis 4. Starch grains roundish in shape, diameter 3—4—8 μ; xylem occupies 1/3 of the radius; fibres numerous Radix Malvae rodundifoliae 3. Cluster crystals absent from the xylem ray; simple pits present on the walls of xylem ray cells and xylem parenchymatous cells Radix Malvae verticilatae 2. Cluster crystals absent, but prisms present in the parenchymatous crystal-sheath cells 3. Simple pits present on the walls of xylem ray cells and xylem parenchymatous cells 4. Taste bitter and astringent; starch grains roundish in shape, diameter 4—6—8 μ, hilum and striations indistinct; xylem occupies 5/7 of the radius (1/2—3/5, if the root is very slender) Radix et Rhizoma Glycyrrhizae pallidiflorae 4. Tasteless; starch grains roundish in shape, diameter 2—15—25 μ, hilum and striations distinct;xylem occupies 1/3—2/5 of the radius Radix Caragarae sinicae 3. Pits absent from the walls of xylem ray cells and xylem parenchymatous cells 4. Xylem occupies 1/2—2/3 of the radius; starch grains roundish or semiglobose, diameter 4—10—15 μ, hilum distinct, striations indistinct Radix Hedysari polybotryos 4. Xylem occupies 4/5—7/8 of the radius; starch grains roundish, diameter 3—4—6 μ, hilum and striations indistinct Radix Medicaginis sativae 1. Crystals of calcium oxalate absent 2. Starch grains present 3. Capillary chromatogram type AC under day light 4. Capillary chromatogram type A₂C under UV light. Formula: α ₁ (yellowish brown or pale yellowish brown)—α₂ (bright pale blue)—γ(brown or pale brownish red) Radix Astragali membranacei or mongholici 4. Capillary chromatogram type A₂BC₂ under UV light 5. γ₁ (bright yellow)—γ₂(purplish red) Radix Astragali chrysopteri 5. γ₁ (pale yellow)—γ₂ (pale greyish purple) Radix Astragali floridi 3. Capillary chromatogram type ABC under day light 4. Capillary chromatogram type A₂BC under UV light, γ (greyish brown) Radix Astragali tongolensis 4. Capillary chromatogram type A₃BC₂ under UV light, γ₁ (purplish brown), γ₂ (dirty yellow).Radix Astragali complanati 2. Starch grains absent 3. Xylem occupies about 1/2 of the radius; ray cells pitted; texture strongly fibrous, difficult to fracture Radix Oxytropicis caeruleae 3. Xylem occupies about 3/4 of the radius; ray cells unpitted; texture hard and brittle, easy to fracture Radix Meliloti albi.