H. viridis: flowers 3-4, large, with spreading yellowish-green sepals. - Woods and thickets in calcareous soil. Fl. March, April.

H. foetidus: flowers numerous, panicled, with large ovate bracts, and converging green sepals often tipped with purple. - Bear's-foot. - Thickets in calcareous soil. Fl. March, April.