Order XII. Iridaceae, Lindl.—Irids, or Corn-Flags.
Flowers with a true perianth adherent to the ovary (inferior ovary), usually hermaphrodite.
Characters.—Calyx and corolla superior, confounded, their divisions partially cohering, or entirely separate, sometimes irregular, the three petals being occasionally very short. Stamens 3, arising from the base of the sepals; filaments distinct or connate; anthers bursting externally lengthwise, fixed by their base, 2-celled. Ovary 3-celled, cells many-seeded; style 1; stigmas 3, often petaloid, sometimes 2-lipped. Capsule 3-celled, 3-valved, with a loculicidal dehiscence. Seeds attached to the inner angle of the cell, sometimes to a central column, becoming loose; albumen horny, or densely fleshy; embryo enclosed within it.—Herbaceous plants, or very seldom under-shrubs, usually smooth; the hairs, if any, simple. Roots tuberous or fibrous. Leaves equitant, and distichous in most genera. Inflorescence terminal, in spikes, corymbs, or panicles, or crowded, sometimes radical. Bracts spathaceous, the partial ones often scarious; the sepals occasionally rather herbaceous (Lindley).
Properties.—The underground stems and roots usually abound in fecula and mucilage; but these nutritive substances are generally combined with an acrid principle, which excludes their employment as articles of food. However, Moraea edulis, M. sisyrinchium, Gladiolus edulis, and a species of Tigridia, have been used as esculent substances. The rhizomes of several species of Iris (as I. Pseudoacorus, I. germanica, I. sibirica, and I. versicolor) are remarkable, especially in the fresh state, for their acridity, in consequence of which some of them have been used as purgatives, sialagogues, or errhines, or for issue-peas. The rhizomes of some species (as I. florentina and I. germanica) have an agreeable smell. The colour and the odour of saffron are to be regarded as part of the petaloid qualities of the stigmata of Crocus. The effects of this medicine on the nervous system are regarded by De Candolle [Essai sur les Propriétés Méd.] as similar to those of [certain odorous] flowers.