Rauvolfia tetraphylla L.

• Title

  Rauvolfia tetraphylla L.

• Authors

  Nathaniel Lord Britton, Frances W. Horne

• Scientific Name

  Rauvolfia tetraphylla L.

• Description

  Flora Borinqueña Rauwolfia tetraphylla Cachinho Milk Bush Family Apocynaceae Dogbane Family Rauwolfia tetraphylla Linnaeus, Species Plantarum 208. 1753. Rauwolfia nitida Jacquin, Enumeratio Systematica Plantarum 14. 1760. Plants which bear more than 2 leaves at each node of the stem or branches are relatively unusual; the tree, or shrub here illustrated, is one of the few having this leaf-arrangement in the Porto Rican Flora. Another Spanish name for it is Palo amargo, its milk-like sap being bitter. It grows in moist and dry districts at lower and middle elevations, on hillsides, in woodlands and in thickets, and ranges nearly throughout the northern West Indies from Jamaica and Cuba eastward to Tortola, recorded, indeed, as extending to St. Barts. It is the type species of the Linnaean genus, Rauwolfia, dedicated to Leonhart Rauwolf, a German botanist, who died in 1596, which consists of 40, or more, species of evergreen trees and shrubs of tropical distribution, with verticillate or opposite, simple leaves, and small flowers in stalked clusters. The calyx is 5-cleft, or 5-parted; the corolla is salverform, with 5, sinistrorse lobes; the 5, short stamens are borne on the corolla, alternate with its lobes, the anthers blunt; the ovary is composed of 2 united or separate carpels, each containing 2 ovules, the style is slender, and the stigma thick. The characteristic fruit is fleshy, small, 2-grooved, compressed, usually 2-lobed, technically consisting of 2, partly united drupes. Rauwolfia tetraphylla is a tree, reaching a maximum height of about 20 meters, usually much lower, sometimes shrubby, with smooth foliage, and slender twigs. The leaves are oblong to lanceolate, from 6 to 15 centimeters long, firm in texture, shining, borne in 3's or 4's on the twigs, or some of them opposite, on stalks from 6 to 12 millimeters long, their many lateral veins widely spreading. The broad flower-clusters are borne on stalks shorter than the leaves, the stalks of the individual flowers very short; the calyx is only about 2 millimeters long, its lobes blunt; the tube of the white corolla is from 4 to 6 millimeters long, its lobes about one-half as long. The red fruit is from 10 to 15 millimeters broad, from 8 to 12 millimeters long, its 2 lobes rounded. Another species, Rauwolfia Lamarckii, occurs in coastal thickets of eastern Porto Rico, on the islands Vieques, Culebra, and Cayo Icacos, and is widely distributed in the West Indies; it differs from Rauwolfia tetraphylla in having dull, thin leaves and smaller, nearly black fruit.