Iridaceae

IRIDACEAE (the iris family), in botany, a family of flower ing plants belonging to the order Liliiflorae of the class Mono cotyledons, containing about Boo species in 6o genera, and widely distributed in temperate and tropical regions. The members of this family are generally perennial herbs growing from a corm as Crocus and Gladiolus, or a rhizome as Iris; more rarely, as the Spanish iris, from a bulb. A few South African representa tives have a shrubby habit. The flowers are hermaphrodite and regular as in Iris and Crocus, or with a symmetry in the median plane as in Gladiolus. The arrangement of the flower parts re sembles that in the nearly allied order Amaryllidaceae (Narcissus, Snowdrop), but differs in the absence of the inner whorl of stamens.

The most important genera are Crocus (q.v.), with about 6o species, Iris (q.v.), with about 200 and Gladiolus (q.v.), with 15o. Ixia, Freesia (q.v.) and Tritonia (including Montbretia), all natives of South Africa, are well known in cultivation.

Sisyrinchium, blue-eyed grass, is a new-world genus of 75 species, extending from arctic America to Patagonia and the Falkland Isles. One species, S. angustifolium, an arctic and temperate North American species, is also native in Galway and Kerry in Ireland. Other British representatives of the family are : Iris Pseudacorus (yellow iris), common by river-banks and ditches, I. foetidissima (stinking iris), Gladiolus illyricus, a rare plant found in the New Forest and the Isle of Wight, and Romulea Columnae, a small plant with narrow recurved leaves a few inches long and a short scape bearing one or more small regular f unnel shaped flowers, which occurs at Dawlish in Devonshire. In the eastern United States there are 10 species of Iris and 13 species of Sisyrinchium, but in the Rocky Mountain region these genera are represented by only 2 or 3 species.