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 prefer the pronunciation for the common name of the plant. The national tree of Peru is in the genus "Cinchona". "Cinchona" plants belong to the family Rubiaceae and are large shrubs or small trees with evergreen foliage, growing in height. The leaves are opposite, rounded to lanceolate and 10–40 cm long. The flowers are white, pink or red, produced in terminal panicles. The fruit is a small capsule containing numerous seeds. A key character of the genus is that the flowers have marginally hairy corolla lobes. The tribe Cinchoneae includes other genera "Cinchonopsis", "Jossia", "Ladenbergia", "Remijia", "Stilpnophyllum", and "Ciliosemina". In