EU'PATO'RIUM (Lat. copatorin, Gk. eura 76pLor, cupatorion, the plant hemp-agriniony; named in honor of Alithridates Eupa tor). A genus of plants of the natural order having small (lower-heads in eorymbs, with the florets all tubular. , The species, about 400 in number, are mostly American, a few oecurring, in Europe and Asia. One only is British. the common hemp-agrimony (Enpa(orium rannobi num ), a slightly aromatic perennial plant, grow Mg mostly in marshy places and on the banks of streams. The root was formerly employed as a purgative, and the plant was also used as a diuretic and as a vulnerary. Thoroughwort, or boneset (P,upatorinm perfolia tam). a species having the opposite leaves joined at the base, is very 4'011111PM in low grounds in North America, and is a popular medicine often administered in intermittent fevers, also as an emetic and purga tive, and, in small doses, as a tonic. It con tains eupatorin (a bitter glueoside), a volatile oil, tannin, etc. The whole plant is very bitter.
Other North American species possess similar properties, and the root of one, known as gravel root, or joe-pye weed (Eapatorium purpureum), is employed as a -diuretic for the relief of the disease from which it derives its name. The ayapana ( Euvatorium triptincrrc), a half- shrub by native of the north of Brazil, has a high reputation in that country as a cure for snake-bites, and has been introduced into the East Indies. It is a very powerful sudorific, and is also diuretic. The Peruvian vulnerary, matico, has been referred, but uncertainly, to a shrubby species of this genus (Eupatorium glutinosum). Guaco, or huaco, much valued in Peru as a cure for snake-bites. is supposed to belong to the allied genus Mikania. For illustration, see Plate Of BON ESET.