LINUM, FLAX, in botany, a genus of the pentandria pentagynia class. The calix consists of five leaves, and the corolla of five petals; the capsule has five valves, and ten cells; and the seeds are solitary. There are 22 species, five of them natives of Britain, viz. the usitatissimum, or common flax; the perenne, or blue flax; the tenuifolium, or narrow-leaved wild flax; the catharticum, or purging flax; and the radiola, least rapture-wort, or all-feed. See FLAX.