richardsonia

Century Dictionary and Cyclopedia

1. n. A genus of gamopetalous plants, belonging to the order Rubiaceæ, the madder family, and to the tribe Spermacoceæ, characterized by three to four ovary-cells, as many style-branches, and a two-to four-celled fruit crowned with from four to eight calyx-lobes, the summit finally falling away from the four lobes or nutlets which constitute its base, and so discharging the four oblong and furrowed seeds. There are 5 or 6 species, natives of warm parts of America. They are erect or prostrate hairy herbs, with a perennial root and round stems, bearing opposite nearly or quite sessile ovate leaves, stipules forming bristly sheaths, and small white or rose-colored flowers in dense heads or whorls. R. scabra, with succulent spreading stems and white flowers, has been extensively naturalized from regions further south in the southern United States, where it is known as Mexican clover, also as Spanish or Florida clover, water-parsley, etc. Though often a weed, it appears to be of some value as a forage-plant, and perhaps of more value as a green manure. The roots of this species, as also of several others, are supplied to the market from Brazil as a substitute for ipecacuanha.