in botany: a genus of the filiculosa order, belonging to the tetradynama class of plants. There are six species; of which the only one worthy of notice is the vernis, or early whitlow-graft. It hath naked stalks, with leaves a little serrated. The blossoms are white, and at night the flowers hang down. It grows on old walls and dry banks. It is one of the earliest flowering plants we have, and is good to eat as a salad. Goats, sheep, and horses eat it; cows are not fond of it; swine refuse it.