This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", 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..
White or yellow slender parasites, dextrorsely twining, the leaves reduced to minute alternate scales, the small white, yellowish or pinkish flowers cymosely clustered. Calyx inferior, 5-lobed or 5-parted (rarely 4-lobed or 4-parted), or of 5 distinct sepals. Corolla campanulate, ovoid, urceolate or cylindric, 5-lobed (rarely 4-lobed), the lobes imbricated in the bud, the tube bearing as many fimbriate or crenulate scales as there are lobes and alternate with them, or these sometimes obsolete. Stamens as many as the corolla-lobes and alternate with them, inserted in the throat or sinuses above the scales, short-exserted or included; filaments short or slender; anthers short, ovate or oval, obtuse, 2-celled, the sacs longitudinally dehiscent. Ovary globose to oblong, 2-celled; ovules 2 in each cavity; styles 2, terminal, separate, or rarely united below; stigmas linear or capitate. Capsule globose or ovoid, circumscissile, irregularly bursting or indehiscent, 1-4-seeded. Seeds glabrous, globose or angular; embryo linear, terete, curved or spiral, its apex bearing 1-4 minute scales, endosperm fleshy; cotyledons none.