perigone

Differing from the true lilies in having the bases of the perigone leaves adherent to the surface of the ovary, so that the latter is apparently below the flower (inferior), and lacking the inner circle of stamens, is the iris family (_Iridaceæ_), represented by the wild blue-flag (_Iris versicolor_) (Fig.  84, _A_, _E_), as well as by numerous cultivated species.

Elements of Structural and Systematic Botany For High Schools and Elementary College Courses Douglas Houghton Campbell

The red specks on the base of the perigone leaves, as well as the red color of the back of the sepals, the stalk, and leaves are due to a purplish red cell sap filling the cells at these points.

Elements of Structural and Systematic Botany For High Schools and Elementary College Courses Douglas Houghton Campbell

The perigone has a twofold purpose, serving both to protect the sporophylls, and, at least in bright-colored flowers, to attract insects which, as we shall see, are important agents in transferring pollen from one flower to another.

Elements of Structural and Systematic Botany For High Schools and Elementary College Courses Douglas Houghton Campbell

The structure of the leaves of the perigone is much like that of the green leaves, but the tissues are somewhat reduced.

Elements of Structural and Systematic Botany For High Schools and Elementary College Courses Douglas Houghton Campbell

There are three circles of leaves forming the perigone, the two outer being more or less membranaceous, and only the three inner petal-like in texture.

Elements of Structural and Systematic Botany For High Schools and Elementary College Courses Douglas Houghton Campbell

These six leaves constitute the perigone of the flower; the three outer are called sepals, the inner ones petals.

Elements of Structural and Systematic Botany For High Schools and Elementary College Courses Douglas Houghton Campbell

In all of these, except _Trillium_, the perigone leaves are colored alike, and the leaves parallel-veined; but in the latter the sepals are green and the leaves broad and netted-veined.

Elements of Structural and Systematic Botany For High Schools and Elementary College Courses Douglas Houghton Campbell

There are two sets of perigone leaves, three in each, and these are usually much alike except the lower (through the twisting of the ovary) of the inner set.

Elements of Structural and Systematic Botany For High Schools and Elementary College Courses Douglas Houghton Campbell

The leaves of the perigone are numerous, and sometimes merge gradually into the stamens, as we find in the common white water-lily (_Castalia_).

Elements of Structural and Systematic Botany For High Schools and Elementary College Courses Douglas Houghton Campbell

The flowers are inconspicuous, borne usually in close spikes, and destitute of a perigone or having this reduced to small scales or hairs.

Elements of Structural and Systematic Botany For High Schools and Elementary College Courses Douglas Houghton Campbell