Description from Flora of China
Herbs perennial. Indumentum (if present) usually glandular. Roots usually fibrous, sometimes thickened and fleshy, or a mixture of both. Rhizome short, rarely cormlike. Leaves basal, tufted, grasslike, lanceolate to linear, with a conspicuous midvein. Scape simple, erect, usually with a few small, bractlike leaves. Inflorescence a terminal raceme, densely capitate or shortly cylindric to laxly elongate, sometimes viscid; rachis pubescent, puberulent, or glabrous. Flowers bisexual, small, distinctly pedicellate or subsessile. Pedicel bearing a bract and bracteole toward either base or apex, pubescent, puberulent, or glabrous; bracteole similar to bract but smaller. Perianth 6-lobed distally, pubescent, puberulent, or glabrous; tube proximally adnate to ovary; lobes erect, spreading, recurved, or revolute. Stamens 6; filaments short; anthers basifixed. Ovary semi-inferior, 3-loculed; ovules many per locule. Style simple, sometimes indistinct; stigma obscurely 3-lobed. Fruit a loculicidal capsule enveloped by persistent perianth, terminating in persistent style and stigma. Seeds numerous, brown, fusiform, to 1.5 mm.
In measurements given in this account, the scape includes the raceme, the flower includes the pedicel, and the capsule includes the persistent style and stigma.
Twenty-one species: Bhutan, China, India, Indonesia, Japan, Kashmir, Korea, Malaysia, Myanmar, Nepal, Philippines, Sikkim; E North America; 15 species (nine endemic) in China.
(Authors: Liang Songyun (梁松筠 Liang Song-jun); Nicholas J. Turland)