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.
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.
In 1718 Sir Thomas and John Lombe set up an improved silkthrowing machine at Derby, and in 1758 Jedediah Strutt introduced a machine for making ribbed stockings, which became famous as the "Derby rib."
The most common are the Natal lily with pink and white ribbed bells, the fire-lily, with flame-coloured blossoms, ixias, gladiolas, the Ifafa lily, with fuchsia-like clusters, and the arum lily.
