A world wide revision of the family with a general discussion of the systematic position, the affinities within the family, the morphology of leaves, flowers, and seeds, the chromosome number, and the geographic distribution. Types of ruminate endosperm of the seed, previously unknown in the family, are illustrated and new types of pearl glands of the leaves are described. A single genus with 34 species is recognized, 32 of which occur in the Indo-Malesian area and 2 are restricted to the Afro-Madagascan area. One new species from New Guinea is described. There is a key to all species, followed by descriptions of the non-Malesian ones and full synonymy of all taxa together with distribution data. A complete revaluation of specific characters has resulted in a new concept of the species, many forms and local species no longer being maintained.