Herbs or undershrubs with 4-angled stems. Leaves opposite or whorled, entire. Flowers in the axil of the upper leaves, cymose or solitary. Calyx-tube costate, straight, equal at the base, 4- to 6-toothed, with an equal number of secondary ones. Petals 4 or 6, large. Stamens 8 to 12, variable in different individuals of the same species. Capsule 1- or 2-celled. About twelve species are found in temperate and tropical regions. The name is adapted from 2 Lythrum 178 gore, from the deep red colour of the flowers.

1. L. Salicaria. Purple Loosestrife. - One of our most showy native plants, growing in marshy places and on the borders of rivulets. Stems about 3 or 4 feet high, the upper portion clothed with rosy purple flowers. There are improved varieties in cultivation, the best of which is that named roseum superbum.