Herbs (with us), with opposite leaves, diandrous (or didy-namous) stamens inserted on the tube of the 2-lipped corolla, and a 2-celled and several-seeded capsule. Seeds flat, supported by hooked projections of the placentas. Flowers commonly much bracted. Calyx 5-cleft. Represented with us by the single genus

Dianthe'ra

Gronov. Water-Willow. D. America'na, L. A perennial herb growing in water or wet places, with entire leaves and purplish flowers in oblong, dense, long-peduncled, axillary spikes. Corolla deeply 2-lipped, the upper erect, notched; the lower spreading, 3-parted. Stamens 2, the anther-cells separated. Pod obovate, flat, 4-seeded.