Their pseudobulbs are round or oblong and each carry one or two lanceolate leaves. Some grow close together in a clustered manner on a short rhizome, while in other species the pseudobulbs keep some distance on an elongate rhizome. This rhizome is clothed in a somewhat transparent, silvery-gray velamen. The flowers grow solitary on short stalks, called scapes, from the base of the pseudobulb. Most are small to very small, but some species carry large, showy flowers. The flowers are never longer than the leaves. Their free petals and sepals have a typically curved and adnate labellum with three inconspicuous lobes. Or the lip may have a distinct callus on the disc ( = central part of the lip from which the lobes radiate). The papillae (= small warts like glands) and the trichomes of the lip show great diversity. The most common form for the papillae is the conical form with rounded or pointed tips.