SPIRÆA, in botany: A genus of plants belonging to the class of icosandria, and to the order of pentagynia; and in the natural system arranged under the 26th order, Pomaceæ. The calyx is quinquelobed; there are five petals; and the capsule is polypermous. There are 18 species; of which two only are British, the filipendula and ulmaria. 1. The filipendula, dropwort, has pinnated leaves; the leaflets are serrated; the stalk is herbaceous, about a foot and a half high, terminated with a loose umbel of white flowers, often tinged with red. The petals are generally six, and the segments of the calyx are reflexed: the stamens are 30 or more; the germina 12 or upwards. It grows in mountainous pastures. 2. The ulmaria, meadow-sweet. The leaves have only two or three pair of pinnae, with a few smaller ones intermixed; the extreme one being larger than the rest, and divided into three lobes. The calyx is reddish; the petals white, and the number of capsules from six to ten twisted in a spiral. The tuberous pea, like roots of the filipendula dried and reduced to powder, have been used instead of bread in times of scarcity. Hogs are very fond of these roots. Cows, goats, sheep, and swine, eat the plant; but horses refuse it. The flowers of the ulmaria have a fragrant scent, which rises in distillation. The whole plant indeed is extremely fragrant, so that the common people of Sweden strew their floors with it on holidays. It has also an astringent quality, and has been found useful in dysenteries, ruptures, and in tanning of leather.