22. (Fig. 41.) ASCLEPIAS. Asclepias.

Fl. ex. 60.

Pleurisy root, E. Knollige Schwalbenwurzel, G. Racine d'asclepiade tubereuse, Fr.

The roots of Asclepias tuberosa L., Asclepiadaceae.

Very light yellowish brown.

Nearly odorless; nauseating when moist.

Somewhat pungent and bitter.

Numerous typical yellow, porous sclerenchyma cells; parenchyma cells rather thin walled containing compound starch granules and prismatic and aggregate crystals of calcium oxalate; large and smaller reticulate and porous ducts.

Roots of related species may be substituted.

23. (Fig. 42.) ASPIDIUM. Aspidium. U. s.

Fl. ex. 60.

Male fern, Male shield fern, E. Wurmfarn, Waldfarn, Johanneswurzel, G. Fougére malé, Fr.

The rhizomes and stipes of Dryopteris Filix-mas Schott, and D. marginale Gray, Filices.

Light greenish brown. Old material brown.

Nearly odorless, recalling taraxacum. Old material has a heavy, nauseating, rancid odor.

Very astringent, sweetish, slightly bitter and pungent.

Largely loosely united parenchyma cells with large simple elliptical starch granules, with lamellations and hili very indistinct; numerous large intercellular spaces with lemon colored resin; vascular tissue typical of the fern group, rather large scalariform ducts; some cork tissue; the resin is of a bright yellowish lemon color.

Ash 3 per cent.

Powdered aspidium is frequently adulterated, the principal adulterant being chaff and refuse. The rhizomes of foreign species are frequently added. Clay, sand and dirt may be excessive. readily attacked by the usual drug parasites and the supply should be carefully watched. The greenish coloration of the freshly powdered article soon changes to yellowish brown.