This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Trees or shrubs, with alternate or rarely opposite pinnately-veined mainly exstipulate leaves, and large axillary or terminal flowers. Flowers regular, mostly perfect. Sepals 5 (rarely 4-7), imbricated, the inner ones generally larger than the outer. Calyx often 2-bracted at the base. Petals 5 (rarely 4-9), hypogynous, imbricated, crenulate. Stamens 00, numerous, hypogynous, more or less united at their bases. Ovary sessile, 2-several-celled; styles 1 or several; ovules 2 or more in each cavity. Fruit a 3-5-celled generally woody capsule with loculicidal or septicidal dehiscence; endosperm little or none; embryo large, with condupli-cate cotyledons.
About 16 genera and 160 species, natives of tropical and warm regions.