LOOSESTRIFE, in botany, the common name of Lysimachia mlgaris, an erect plant, 2 to 4 ft. high, common on river banks in England; the branched stem bears tapering leaves in pairs or whorls, and terminal panicles of rather large deep yellow flowers. It is a member of the primrose family. L. nemorum, yellow pimpernel, or wood loosestrife, a low-growing plant with slender spreading stem, and somewhat similar yellow flowers standing singly in the leaf-axils, is frequent in copses. L. Nummnlaria is the well-known creeping jenny or money-wort, a larger plant with widely creeping stem, pairs of shining leaves and large solitary yellow flowers; it is found on banks of rivers and damp woods, and is a common rockery plant. Purple loosestrife, Lythrum Salicaria, belongs to a different family, Lythraceae. It is a handsome plant growing 2 to 6 ft. high on river banks and ditches, with a branched angled stem bearing whorls of narrow pointed stalkless leaves and ending in tall tapering spikes of beautiful rose-purple flowers. The flowers are trimorphic, that is to say, exist in three forms which differ in the relative length of the styles and stamens and are known as longstyled, mid-styled and short-styled forms respectively; the size and colour of the pollen also differ. These differences play an important part in the pollination of the flower.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)