LAMIACEAE,  Mint Family

Usually aromatic herbs or rarely shrubs; stems square; leaves opposite; flowers hypogynous, perfect, in whorls (or rarely solitary) in axils of foliage leaves; or in axils of bracts, then whorls or solitary flowers in spikes or racemes; or whorls 1-few at or near summit of stem; calyx usually 5-Iobed or -toothed, sometimes 2-lipped; corolla zygomorpbic; rarely almost regular, of 5 petals, usually 5-lobed or sometimes apparently 4-lobed, usually 2-lipped, upper lip usually 2-lobed, lower lip usually 3-lobed; stamens 4 or 2, on the corolla, when 4, usually of 2 lengths, when 2, the other pair sometimes present as vestiges; pollen-sacs parallel or their bases divergent, in extreme condition the sacs lying end to end in a straight line perpendicular to filament; carpels 2, united, ovary 4-lobed, 1 ovule in each lobe; style 1, bifid at tip; fruit enclosed in persistent calyx, separating into 4 one-seeded nutlets; in genera Nos. 1-3, style terminal, nutlets laterally attached; in the other genera, style basal, nutlets basally attached (Labiatae, nom. altern.)