(from δώδεκα τριάς, and ανθος, a man); the name of the eleventh class in Linnaeus's sexual system, consisting of plants with hermaphrodite flowers, that, according to the title, have twelve stamens or male organs. This class, however, is not limited with respect to the number of stamens. Many genera have sixteen, eighteen, and even nineteen stamens; the essential character seems to be, that, in the class in question, the stamens, however numerous, are inserted into the receptacle; whereas in the next class, icelandria, which is as little determined in point of number as the present, they are attached to the inside of the calyx or flower-cup.

The orders in this clas, which are six, are founded upon the number of the styles, or female organs. A. sarabacca, mangoflora, florax, purple loose-strife, wild Syrian rue, and purslane, have only one style; agrimony and heliocarpus have two; burning thorny plant, and bastard rocket, three; glaucus, five; illicium, eight; and house-leek, twelve.