Deciduous or rarely evergreen; bulb subterranean or epigeal, subglobose or rarely poorly developed and rootstock rhizomatous, tunics sometimes scale-like or loosely overlapping, rarely fragmenting into wedge-shaped segments, usually white but rarely pinkish; outer bulb tunics membranous, papery or leathery. Leaves 1 to several, green or dry at flowering, erect or spreading, linear to oblong or filiform, sometimes very succulent, usually glabrous but sometimes pubescent or glandularpubescent, margins smooth, ciliate, fringed, or hyaline, sheaths sometimes persistent and forming a papery or weakly to strongly fibrous, sometimes horizontally barred sheath around base of stem. Inflorescence a several- to many-flowered raceme, sometimes subcorymbose with shortened axis, or secund, usually solitary but sometimes more than one; peduncle rarely papillate; bracts membranous or leafy, small or large, not spurred; bracteoles usually lacking but sometimes thread-like and borne on alternate sides of pedicels at base; pedicels short or long. Flowers white, yellow, orange, or yellowish green, with or without darker keels, scented or unscented, sometimes closing at night or more rarely nocturnal, suberect, patent or nodding, rotate, campanulate or more or less tubular, rarely weakly zygomorphic; tepals ovate to narrowly lanceolate, persistent, more or less shortly united at base or less commonly united into a distinct tube, spreading to erect, sometimes with tips reflexed, sometimes weakly to markedly dimorphic, the inner sometimes erect and more or less connivent around stamens and style and cupped or hooded and papillate at tips or developing a fleshy apical knob or flap that can be conspicuously hinged, the outer sometimes with a caudate apical appendage; stamens suberect or lightly spreading, filaments free or rarely united below, fused to base of tepals or inserted at top of tube, filiform to lanceolate, all similar or inner usually broader, both whorls or more usually inner variously expanded or toothed below, rarely membranous and closely appressed to perianth when anthers apparently sessile; anthers of outer stamens sometimes smaller or vestigial or absent; ovary ovoid to globose or turbinate, sometimes shortly stipitate, rarely with 3 apical knobs, smooth or with distinct paraseptal crests; ovules few to many per locule; style vestigial to long, cylindrical and sometimes slightly deflexed or subcylindrical or more or less trigonous or prismatic and then strongly papillate; stigma small and 3-lobed or -angled or pyramidal to large and capitate and then distinctly papillate and sometimes fringed with longer papillae. Capsule fusiform, ovoid to globose, more or less 3-angled or -lobed, membranous or leathery, enclosed in dry perianth or exposed, dehiscing loculicidally; seeds few to many per locule, flattened or angled to discoid, sometimes stacked tightly one on top of another, black, testa tightly adhering. x=9, other base numbers 12, 11, 8, 7, 6, 4.