Infl. us. lateral, 1-∞-fld; floral bracts often very small. Per. us. large and showy; dorsal sepal uppermost, free; lateral sepals adnate to column-foot (forming a mentum); petals > or < sepals, us. thinner. Labellum ± 3-lobed, claw attached to end of column-foot, disc often longitudinally lamellate but rarely with calli. Column short, ± winged, foot long; anther terminal, operculate, incumbent, narrowly joined to column just below its apex, caducous, pollinia 4, ± waxy, without caudicles; stigma deeply concave, separated from anther by narrow transverse flap. Plants epiphytic or rupestral; growth sympodial; stems ± elongated, sts swollen into fleshy pseudobulbs. Lvs variously shaped, jointed to sheath. Genus of nearly 1,000 spp. from India and Ceylon to southern China and Japan, southwards through Malaya far into the Pacific and to Australia, the one N.Z. sp. endemic.