Dryopteris filix-mas (Male fern)

Shows typical English fern with new emerging wheel-shaped frond. Contains contain aspidin and filicic acid. Used for treating tapeworm infestation and made famous when Louis XVI paid Madame Nouffer 1800 francs for her secret recipe - powdered root and lime blossom water, followed by caster oil. Cushions and mattresses have been stuffed with the fronds as prevention against rheumatism.