(Plates 126–130; Fig. 707.1–707.4) Epiphytic or occasionally lithophytic herbs. Roots usually emerging from nodes near base or lower portion of stem. Stem usually stiffly erect, completely enclosed by distichously arranged persistent leaf-sheaths. Leaves distichous, rigid, usually decurved or held erect, linear or oblong, adaxial surface channelled shallowly to deeply, jointed and sheathing at base, deciduous, apex premorse. Inflorescence axillary, racemose, few- to many-flowered, floral bracts triangular. Flowers resupinate, usually widely opening, exhibiting a wide range of colours and patterning. Sepals and petals free, similar, elliptic-obovate, twisted or undulate, often tessellated, margins often reflexed, often narrowed at base. Labellum usually rigidly attached but occasionally articulate, trilobed, side lobes orbicular to pointed, midlobe simple, deltoid or bilobed to fimbriate, usually shortly spurred but occasionally no spur or with an elongate, nectiferous spur; spur often with thickenings at entrance. Column usually lacking a foot; pollinia two, waxy, spherical, grooved; rostellum shelf-like.