Violet, or Viola, L. a genus of plants, consisting of 44 species; of which the following are the principal :

1. The canina. See Dog's Violet.

2. The tricolor. See Heart's Ease.

3. The odorata, or Sweet Violet, is perennial; grows in warm lanes, hedges, and ditch-banks, especially in clayey or marly soils ; flowers in the months of April and May. - Both the blossoms and seeds of this plant are mildly laxative ; and, when taken in doses of from 40 to 80 grains, the powdered root operates as a purgative, and likewise as an emetic. - Large quantities of violets are cultivated at Stratford-upon-Avon, for their petals, to impart the colour to syrup of violets ; an officinal preparation of which is kept in the shops, and proves an agreeable and useful laxative for children. Such syrup may also be employed in many chemical inquiries, for discovering the presence of an acid, or an alkali; the former changing the blue colour to a red, and the latter to a green ; though slips of white paper, stained with this juice, and preserved from the access of air and light, may serve as a substitute for that purpose.