Note 3 — Dicotyledonous, Gamopetalous.
Jerome Beers Thomas translation
The chemical composition of the root has been studied by Dulong.3 It includes a non-nitrogenous principle, plumbagin, existing in the form of orange-yellow needles, bitter, acrid, volatile, neutral, slightly soluble in cold water, more soluble in ether, alcohol and hot water. The aqueous solution becomes cherry-red on the addition of an alkali, which color is changed to yellow by acids. Basic acetate of lead causes the same color change.