LOMENTACEÆ, in botany, (from lomentum, a colour used by painters), the name of the 3rd order in Linnaeus's fragments of a natural method, consisting of the following genera, many of which furnish beautiful tinctures that are used in dyeing, viz. adenanthera, baubinia, cæsalpina, cassia, ceratonia, cercis, gleditsia, guilandina, hamatoxylon, hymenæa, mimosa, parkintonia, poinciana, polygama. See BOTANY, p. 1311.