This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Erect perennial scarcely succulent herbs, with alternate sessile serrate thin leaves, and greenish perfect flowers in forked secund cymes. Calyx 5-parted or 6-parted. Petals usually wanting, if present 5 or 6. Stamens twice as many as the sepals, hypogynous; filaments filiform. Carpels 5 or 6, united to the middle, ovules ∞. Fruit depressed, 5-6-lobed, 5-6-beaked, the lobes dehiscent, tipped with divergent styles, many-seeded.
The family consists of the following genus.