IMPATIENS, in botany, a genus of the Syngenesia Monogynia class and order. Natural order of Corydales. Gerania, Jus sieu. Essential character ; calyx two leaved : corolla five-petalled, irregular, with a cow.f.ed nectary ; capsule superior, five-valved. There are twelve species, of which I. balsamina, garden balsam, is an annual plant, about a foot and a half in height, dividing into many succulent branches ; leaves long and serrate ; the flowers come out from the joints of the stem, upon slender peduncles, an inch in length, each sustaining a single flower. In its wild state it is two feet, or more, in height, round, hispid, juicy, with a white stem, and ascending branches. It is a na tive of the East Indies, China, Cochin China, and Japan ; the Japanese use the juice prepared with slum for dyeing their nails red. By culture this plant is very much enlarge d,and becomes very branch ing. Mr. Millar tells us, he has seen the
stem seven inches in circuit, and all the plants large in proportion, branched from top to bottom, loaded with its party-co loured flowers, thus forming a mostbeau tiful bush. The varieties which cultiva tion has produced in this elegant flower are numerous.
I. noli tangere, common yellow balsam, is also an annual plant ; during the day the leaves are expanded, but at night they hang pendent, contrary to what is observ ed in most plants, which, from a deficien cy of moisture, or a too great perspiration from heat, commonly droop their leaves in the day-time. When the seeds are ripe, upon touching the capsule they are thrown out with considerable force : hence the Latin name "impatiens," and "noli tangere." The whole plant is con siderably acrid, and no quadruped, ex cept perhaps the goat, will eat it.