EPILOBIUM, in botany, the WILLOW HERE, a genus of the octandria monogynia class. The calix is divided into four segments, and the corolla consists of four petals; the capsule is oblong and below the flower; and the seeds are pappous. There are seven species, all of them natives of Britain, viz. the angustifolium, or rolebay
rosebay willow-herb; the hirsutum, or small-flowered hairy willow-herb; the ramosum, great-flowered willow-herb, or codlings and cream; the montanum, or smooth-leaved willow-herb; the tetragonum, or narrow-leaved willow-herb; the palustre, or marsh willow-herb; and the alpinum, or mountain willow-herb.