Herbs, sometimes subshrubby, with grooved stems and central pith in stems; leaves alternate, usually compound; petioles ligulate; flowers perfect or rarely unisexual, usually in compound or simple umbels or heads; calyx 5-lobed; petals 5; stamens 5, inflexed in bud; anthers 2-celled; ovary inferior, 2-celled; cells 1- ovulate; ovules pendulous; fruit dry 2-celled, splitting into 2 segments; seeds en- dospermous. Usually aromatic pungent and spicy tissues, especially the seeds. About 200 genera and 3000 species, chiefly in temperate regions, cosmopolitan. One indigenous species, two introduced, in Guam.