Adiantum L.
Sporangia borne on veins or extending to interspaces on inner face of reflex portions of lamina margin; pedicel slender, annulus incomplete, vertical. Spores tetrahedral to bilateral, smooth, us. dark. Rhizome far-creeping to short and ascending, with narrow dark paleae. Lamina pinnately decompound to simply pinnate, mostly firm. Some 200 terrestrial spp. of wide distribution.
Key
Fig. 3. ADIANTUM. Reflexed lamina-margins protecting sori. © All rights reserved. [Image: 4X1D]