The Polygalaceae or milkwort family contains about 1000 species in 20 genera distributed almost worldwide but absent from New Zealand and other southern Pacific islands and the very Northern Hemisphere. It is in the order Fabales with its sister family Fabaceae. The family is composed of mainly herbs and shrubs, with a few trees and climbers. Over half the family members are in the genus Polygala, which derives its name from the Greek polys, "much," and gala, "milk." It was so named because it was thought originally (and incorrectly) to stimulate breast milk and not because it contains milky sap. The leaves are simple, estipulate and usually alternate, and the flowers are usually zygomorphic and often share a resemblance with the legumes, with corollas typically of 3 petals, the median anterior of which is keel-like and sometimes with a fringed crest. Often used in local medicines.