The Irones and Their Precursors

Abstract

The sword lilies or irises are monocotyledons, perennial plants of great beauty like their close relatives in the order Liliflorae, the lilies and the amaryllises. They are widely distributed all over the northern hemisphere from swamp land to arid zones, from coastal to mountain habitats, and propagate by rhizomes, tubers, or bulbs from which the long sessile grass- or sword-shaped, parallel-ribbed leaves sprout which give the family its name. The radial, showy flowers have the typical three-fold symmetry of Lilideae: brightly purple, blue, yellow or white coloured petals, each set often different and, hanging or upright, they stand in two circles of three. The flowers are visited by bumble bees in the beginning, later on mostly by hovering flies or bees; accordingly, the construction of the petals, stamina and stigmata is hercogamous so that self-pollination is excluded. They possess only one triad of stamina (in contrast to the lilies proper), a low standing ovary, forming on maturation a three-locular fruit capsule that opens to various degrees of dehidescence to shed brown, red or cream-coloured disc-like seeds. Most sword lilies bloom in May or June and the seeds mature and spread in high summer.