Dennstaedtiaceae

Terrestrial ferns with creeping or more rarely erect rhizomes which are clothed with simple hairs or more rarely with pleuricellular hairs (as in Histiopteris) or rarely with dark scales, solenostelic or dictyostelic. Fronds usually scattered along the rhizome or sometimes in a tuft at the apex of an erect rhizome. Lamina mostly decompound or sometimes 1–2-pinnate, coriaceous or herbaceous, mostly uniform or almost so. Ultimate segments usually oblique at the base, hairy or glabrous. Veins free or rarely anastomosing without free vein endings in the areolae (Fig. 15). Sori round or linear, marginal or submarginal, terminal on the free veins or sometimes borne on a vascular commissure joining the vein-endings. Indusium in the New South Wales species cupuliform or pouch-shaped, 2-valved, rounded or linear (with an outer false indusium and an inner true indusium) or 1-valved and composed of a small, reflexed, marginal flap or the linear, reflexed, margin of the lamina. Paraphyses present or absent. Sporangia basipetal, gradate or mixed in origin; the annulus with 13–23 indurated cells, longitudinal and interrupted by the pedicel; the stomium definite; the pedicel long, slender, with 2 rows of cells. Spores tetrahedral or sometimes bilateral, without a perispore. c. 12 gen., trop. to temp.