by Nathaniel Lord Britton & Addison Brown

“ Asexual propagation consisting of sporocarps borne on peduncles which rise from the rootstock near the leaf-stalk or are consolidated with it, containing both megaspores and microspores. The megaspores germinate into prothallia which bear mostly archegonia, while the microspores grow into prothallia bearing the antheridia. ”

“ Marsh or aquatic plants, the leaves commonly floating on the surface of shallow water, slender-petioled, 4-foliolate. Peduncles shorter than the petioles, arising from their bases or more or less adnate to them. ”