Edward Stone (natural philosopher) piece of bark from a willow tree and was struck by its extremely bitter taste. Knowing that the bark of the Peruvian cinchona tree − from which quinine (used in the treatment of malarial fevers) is derived − has a similarly bitter taste, he surmised that the willow might also have therapeutic properties. Stone's interest in willows was due to the ancient "doctrine of signatures" – whereby the cause of a disease offers a clue to its treatment. According to Stone: "As this tree delights in a moist or wet soil, where agues chiefly abound, the general maxim that many
Cinchona officinalis of malaria. Other alkaloids that are extracted from this tree include cinchonine, cinchonidine and quinidine. Cinchona officinalis Cinchona officinalis is a South American tree in the Rubiaceae family. It is native to wet montane forests in Colombia, Ecuador, Peru and Bolivia, between 1600–2700 meters above sea level. Cinchona officinalis is a shrub or tree with rugose bark and branchlets covered in minute hairs. Stipules lanceolate or oblong, acute or obtuse, glabrous. Leaves lanceolate to elliptic or ovate, usually about 10 cm. long and 3.5–4 cm. wide; acute, acuminate, or obtuse tip; base rounded to attenuate; coriaceous, glabrous above and often