This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Erect or prostrate shrubs, or small trees, with alternate simple leaves, and small clustered or solitary perfect flowers, the pedicels commonly bracted. Calyx-tube adnate to the ovary, the limb 4-5-lobed or 4-5-cleft. Corolla gamopetalous, 4-5-lobed, or rarely divided into separate petals, deciduous, globose, campanulate, urceolate, or tubular. Stamens twice as many as the corolla-lobes, epigynous, or inserted at the base of the corolla; filaments usually flattened, mostly short; anthers dorsally attached, 2-celled, the connective entire or 2-awned. Ovary inferior, 2-10-celled, crowned by the epigynous disk; style filiform; stigma simple, or minutely 4-5-dentate; ovules solitary, or several in each cavity, anatropous. Fruit a berry or drupe in our genera, globose; cells I-several-seeded, or the drupe containing several nutlets. Seeds compressed; testa bony; endosperm fleshy; embryo central; radicle near the hilum.
About 20 genera and .100 species of wide geographic distribution.
Ovary 10-celled; fruit a berry-like drupe with 10 I-seeded nutlets.
Ovary 4-5-celled; fruit a many-seeded berry.
Corolla open-campanulate, 4-5-lobed.
Flowers 4-parted; leaves small, coriaceous, persistent; low shrub.
Flowers 5-parted; leaves large, thin, deciduous; tall shrubs.
Flower not jointed with its pedicel; anthers exserted.
Flower jointed with its pedicel; anthers included; berry black.
Corolla cylindric, subglobose or urceolate.
Erect shrubs; ovary entirely inferior; berries normally not white.
Low trailing shrub; ovary half inferior; berry snow-white.
Corolla deeply 4-cleft or 4-divided, the lobes reflexed.