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.
Another large assemblage of trees and shrubs, and including a few herbaceous species. Natives of the tropics of all countries, and particularly numerous in America, a few reaching the temperate regions. The members of this order are easily recognised by their opposite exstipulate leaves with parallel nerves, definite stamens, anthers usually opening by pores, and the filaments furnished with an appendage.