Rhizome and stipes of Dryopteris filix-mas (L.) Schott., Polypodiaceae. Habit. North America, Northern Asia, Europe, Northern Africa. Constit. Filicic and flavaspidic acids, volatile oil, asbaspidin, filicin, filmaron, filix red, resin. It yields not less than 6.5% oleoresin (U.S.P.).
Oleoresin of male fern. An ether extract of male fern containing not less than 24% crude filicin.
Anthelmintic (Cestodes).