HIPPURIS, MARE'S-TAIL; a genus of the monandria order, belonging to the monogynia class of plants. There is only one species, a native of Britain, and which grows in ditches and stagnant waters. The flower of this plant is found at the base of each leaf, and is as simple as can be conceived; there being neither empanelment nor blossom; and only one chive, one pointal, and one seed. It is a very weak astringent. Goats eat it; cows, sheep, horses, and swine, refuse it.