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, herbs or shrubs, with alternate simple or compound mostly stipulate leaves. Flowers mostly clustered and perfect, sometimes monoecious, dioecious or polygamous, nearly regular, or irregular. Calyx mostly of 5 sepals or 5-toothed. Petals usually 5, imbricated, and the upper (unpaired) one enclosed by the lateral ones in the bud. Stamens 10 or fewer in our genera, the filaments distinct, or more or less united. Ovary 1-celled, 1-many-ovuled. Fruit a legume, mostly dehiscent into 2 valves. Seeds with or without endosperm.
About 90 genera and 1000 species, mostly of tropical distribution.
trees or shrubs; leaves simple; corolla irregular, apparently papilionaceous, but the lateral petals
enclosing the upper one in the bud.
Herbs (all our species); flowers perfect; leaves pinnate or bipinnate; corolla nearly regular.
Leaves pinnate, not punctate.
Pods not elastically dehiscent; leaves not sensitive to touch.
Pods elastically dehiscent, leaves sensitive to touch.
Leaves bipinnate, glandular-punctate.
Trees; leaves pinnate or bipinnate; flowers dioecious or polygamous.
Receptacle short; stamens 3-5; pod flat, short or elongated.
Receptacle elongated; stamens 10; pod oblong, woody.