BRYONY (Bryonia dioica), a twining plant of the gourd family (Cucurbitaceae), native to Europe and Western Asia and common in England. It has a large white root, large palmate leaves, pale yellow flowers in axillary clusters and red berries. The black bryony (Tamus communis), a climbing plant of the yam family (Dioscoreaceae), of similar range, bears a black root, shining, heart-shaped leaves and scarlet berries. Both plants are poisonous but yield useful drugs.