Note: Do not rely on this information. It is very old.
UrticaceaeUrticaceae, an order comprising 1,500 species in 108 genera, occurring in all parts of the world, but mainly tropical. Its members all agree in their apetalous flowers, with stamens equal in number and opposite to the sepals, and superior, one-chambered, one-ovuled ovary; but it includes such varied types that it has been termed "the marine-store shop of botanists," and is often separated into the orders Urticeae, Moreae, Ulmaceae, Celtideae, and Cannabineae -- i.e. that nettles, mulberries and figs, etc., elms, Celtis, and hemp and hops. These groups differ in their latex, stipules, albumen, and in the direction of their ovules. The Urticeae comprise over 40 genera and 500 species, with erect atropous ovules, albuminous seeds, and very tough fibrous inter bark. With the exception of the two British genera, the nettles (Urtica) and (Parietaria), they are all essentially tropical. The most useful genus is Boehmeria.