Helian'themum canaden'se, Helianthemum, Rock-rose, Frost-wort (-weed), U.S.P. 1850-1870. -- Cistaceae. The dried herb; N. America. Hoary perennial. 15-45 Cm. (6-18') high, terete, reddish; leaves 1-3 Cm. (2/5-1 1/5') long, 4-8 Mm. (1/6-1/3') broad, oblong, entire; flowers, 2 kinds, yellow; fruit ovoid capsule; odor slightly aromatic; taste astringent, bitter; solvent: diluted alcohol; contains volatile oil, fixed oil, wax, tannin, glucoside. Tonic, astringent, alterative; prurigo; large doses emetic. Dose, gr. 5-30 (.3-2 Gm.); Decoction, Extract, Fluidextract (diluted alcohol).