作者

DEVOL, CHARLES E.

型態特徵

Usually aquatic perennials, growing submersed, emersed or rarely terrestrial; stem corm-like,2-4 lobed giving rise to numerous dichotomously branching roots and a tuft of elongated grass-like leaves. Leaves with 4 longitudinal air-channels and a central vascular strand, some species with peripheral vascular strands, many species with stomata. Sporangia large, borne at base of sporophylls, containing either large tetrahedral megaspores, or minute ellipsoidal microspores; ligule borne above sporangium; a thin velum often more or less covering the sporangium; basal portion of sporophylls expanded, winged. Megaspores white, gray or black, smooth, warty, echinate or reticulate.

屬

A family with only one genus.

參考文獻