Perennial herbs with thick rhizomes, dioecious. Leaves compound 1-3-pinnate, rarely 3-foliolate; stipules absent. Inflorescence a much branched, many-flowered, terminal panicle; bracts and bracteoles usually present. Flowers subsessile to pedicillate, unisexual (rarely bisexual), hypanthium shallowly cupular with a ring-like disk on the rim. Sepals 5, triangular, adnate to the hypanthium, valvate in bud. Petals 5, whitish, obovate. Male flowers: stamens 15-30, attached to ring, longer than petals, usually with 3-5 rudimentary carpels. Female flowers: ovary surperior, carpels 3-5(-8), free; stylodia terminal; filaments short, anthers abortive. Fruit a follicetum. Follicles 3-5, pendulous in fruit, dehiscing by a ventral suture. Seeds few, small, with thin endosperm.

A genus of one polymorphic species, distributed in the northern temperate zone. Represented in Pakistan by one subspecies.