Calendula consists of the dried ligulate florets of the common marigold, Calendula officinalis, Linn. (N.O. Compositae), a native of the Levant and South Europe, but now found in all parts of England. It is official in the U.S.P. The ligulate ray florets are collected when the flowers are fully open, and dried. The florets are yellow or orange-coloured, about 15 to 25 millimetres long and 3 millimetres broad, the short, hairy tube generally enclosing the remains of a filiform style and bifid stigma. The limb of the corolla terminates in three teeth, and has four veins. The odour is slightly aromatic and the taste bitter.
Constituents.—The chief constituents of the drug are a tasteless yellow substance named calendulin, a bitter principle, and traces of volatile oil.
Action and Uses.—Calendula was at one time believed to have the power of promoting the absorption of blood effusions. The tincture has been administered for amenorrhoea, in doses of 3 to 12 decimils (1.2 milliliters) (5 to 20 minims); it is also used, diluted with from 9 to 19 parts of water, as a lotion for sprains and bruises.
- Tinctura Calendulae, U.S.P.—TINCTURE OF CALENDULA.
- Calendula, in No. 20 powder, 20; alcohol (95 per cent.), to 100. Prepared by percolation.