Rubiaceae

Rubiaceae, the third largest order of Dicotyledons, comprising over 4,000 species in nearly 350 genera. Though the tribe Galieae, which is largely represented in England, including Bed-straw. Galium), whence the family is named, Woodruff, Madder, etc., is almost exclusively temperate, the other twenty-four are mainly tropical. They include plants of all sizes, usually with square stems. The leaves are opposite and decussate, simple and stipulate, the stipules in Galieae being as large as the leaves. The floral whorls have 4 to 6 leaves each and alternate, there being only one whorl of stamens and, as a rule, only two carpels. Both calyx and corolla have their leaves united, and are generally polysymmetric. The ovary is inferior, the fruit various, and the seeds generally albuminous. The order includes the Cinchonas, Ipecacuanha, Coffee, and Gambir, which are noticed separately, besides the fragrant Bouvardia, Rondeletia, and Gardenia of our greenhouses.