Uniaperturate pollen, apocarpous gynoecium and numerous stamens in a centripetal sequence.
Petals are free.
Some with vesselless wood, laminar stamens and more than two cotyledons. Many have volatile oils. For more information on angiosperm structure see Encyclopaedia Brittanica for detailed information.- Summary from the University of Wisconsin . More information, in German, from the University of Hamburg with discussions on each of the orders and some illustrations as well as diagnostic characters and information from the University of Lethbridge . Widespread in tropical and warm temperate, especially North America and southeastern Asia.