Fagaceae (Cupuliferae). Distinguished by small flowers, monoecious, staminate - aments, pistillate subtended by involucre (united bracts) becoming a bur (cup), petals none, stamens 4-20, perianth 4-8-lobed; composed of 5 genera, 375 species. Quercus.
Ulmaceae. Distinguished by fugacious stipules, small flowers, monoecious, dioecious, perfect or polygamous, perianth 3-9-parted, or sepals, petals none, stamens 3-9, ovary 1-celled, superior, samara, drupe or nut; composed of 13 genera, 140 species. Ulmus.
Moraceae. Distinguished by having milky juice, small flowers, monoecious, dioecious, calyx 4-5-parted, petals none, stamens 4-5, ovary 1-celled, superior, fruit various; composed of 55 genera, 925 species. Humulus, Cannabis.
Santalaceae. Distinguished by calyx 4-5 valvate-lobed, green or petaloid, stamens perigynous, sheathing disk, ovules suspended by funiculus; composed of 26 genera, 250 species. Santalum.
Aristolochiaceae. Distinguished by colored, irregular calyx, epigynous stamens, fruit capsule, many-seeded, leaves cordate; composed of 5 genera, 200 species. Aristolochia.
Polygonaceae. Distinguished by stems having many swollen joints, ochriate stipules above each, flowers perfect, calyx colored or greenish, ovary superior, 1-celled; composed of 30 genera, 800 species. Rheum.
Chenopodiaceae. Distinguished by succulency and flowers being ebracteated, minute, greenish, perfect or unisexual, ovary superior, 1-celled, fruit 1-seeded utricle; composed of 75 genera, 550 species. Chenopodium.
Myristicaceae. Distinguished by leaves alternate, dotted, leathery, flowers dioecious, regular, calyx 3-4-cleft, filaments 3-12, united, ovary 1-celled, ovule 1, fruit succulent; composed of 5 genera, 100 species. Myristica.
Ranuneulaceae. Distinguished by flowers being most complete, organs all distinct, no adhesions nor cohesion, often yellow; composed of 35 genera, 1050 species. Hydrastis, Cimicifuga, Delphinium, Aconitum.