This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
Evergreen or deciduous, often aromatic trees or shrubs. Leaves alternate, simple, usually entire, with convolute or opposite deciduous stipules, or exstipulate. Flowers axillary or terminal, usually solitary, often large and showy. Sepals and petals hypogynous, in 3 or more series, imbricate. Stamens numerous; filaments often dilated or fleshy. Carpels usually numerous, free or cohering together, verticillate or imbricated, and inserted upon a more or less elongated or enlarged torus, either opening in valves or rarely across the base, or woody, or fleshy and indehiscent. Seeds 1 or 2 or more; testa crustaceous or double, the outer crustaceous and the inner fleshy; albumen copious, oleaginous, not ruminated. A very distinct order amongst hardy trees and shrubs, and one which furnishes some of the handsomest ornaments of our gardens.