Exot. Fl. 2: plate 103. 1824.
Herbs epiphytic, lithophytic, or terrestrial. Roots velamentous. Stems slender or pseudobulbous, clustered or distant along rhizome. Leaves 1–several, conduplicate, thin [fleshy], leathery. Inflorescences terminal, simple or paniculate racemes with ± secund branches; peduncle enclosed by scarious sheaths. Flowers few to many, mostly not resupinate, generally small; dorsal sepal free; lateral sepals adnate to column foot forming mentum; petals smaller than sepals, free; lip 3-lobed [simple], adnate to and articulate with column foot, forming part of mentum; disc usually callose, pubescent; column semiterete, short; foot distinct; stigmas confluent, transverse under rostellum, viscidium ovate to elliptic; anther terminal, incumbent, operculate; pollinia 4, globose or ellipsoid, hard, waxy, attached to single short stipe. Fruits capsules.
Tropical and subtropical regions, especially rich in Africa, s Fla., Mexico, West Indies, Central America, South America, Asia, Australia, Pacific Islands.
Species 150 (1 in the flora).