Scape. - A few inches to several feet high. Leaves. - Arrow-shaped. Flowers. - White, unisexual, in whorls of three on the leafless scape. Calyx. - Of three sepals. Corolla, - Of three white, rounded petals. Stamens and Pistils. - Indefinite in number, occurring indifferent flowers, the lower whorls of flowers usually being pistillate, the upper staminate.

Plate XXIX. Arrow-Head. - S. variabilis

Among our water-flowers none are more delicately lovely than those of the arrow-head. Fortunately the ugly and inconspicuous female flowers grow on the lower whorls, while the male ones, with their snowy petals and golden centres, are arranged about the upper part of the scape, where the eye first falls. It is a pleasure to chance upon a slow stream whose margins are bordered with these fragile blossoms and bright, arrow-shaped leaves.