They have the fleshy stems characteristic of the order, these being either globose, oblong or cylindrical, and either ribbed as in Melocactus, or broken up into distinct tubercles, and most of them armed with stiff sharp pines, set in little woolly cushions occupying the place of the buds.
Long, elliptic-ovate, doubly toothed, pointed, numerously ribbed, hairy below and opaque, and not glossy as in the beech, have short stalks and when young are plaited.
Well ribbed up, short and compact in proportion.
They are dwarf, ribbed, globose or cylindrical plants; and the flowers, which are produced from the side instead of the apex of the stem, are large, and in some cases very beautiful, being remarkable for the length of the tube, which is more or less covered with bristly hairs.
Pretty liliaceous plants, with simple conspicuously longitudinal-ribbed leaves, the racemose flowers funnel-shaped and deflexed.