Terrestrial or climbing ferns. Rhizome creeping or erect, sometimes forming a short trunk, dictyostelic (often complex), dorsiventral in some genera, clothed with non-clathrate, mostly non-peltate scales which lack stiff unicellular hairs; the marginal teeth of these scales usually formed by 2 adjacent cells. Stipes mostly not articulated to the rhizome, with 3–7 vascular strands. Fronds uniform or dimorphic. Lamina simple to pinnately decompound or sometimes flabellate, often basiscopically produced, glabrous or clothed with multicellular hairs. Rhachises and costae glabrous, papillate or clothed with multicellular hairs. Costae grooved or raised. Pinnae articulated or not articulated to the rhachis. Veins free or anastomosing, with or without free veinlets in the areolae, anadromous or catadromous. Sori indusiate or rarely exindusiate, mostly dorsal or terminal on the veinlets, rarely marginal or projecting beyond the margin, usually orbicular and comparatively small but sometimes oblong or linear or aristichoid and spreading along the veins. Indusium peltate, reniform, oblong or linear. Sporangia with pedicels composed of 1 or 3 rows of cells; the annulus longitudinal, interrupted by the pedicel, including 10–40 thick-walled cells (usually under 20 in genera occurring in Australia). Spores bilateral, monolete, usually with a perispore. 29 gen., cosmop.