Roots not proliferous. Stems erect or ascending, usually unbranched; scales dark brown throughout, narrowly deltate, 2--3 × (0.2--)0.5--1 mm, margins entire. Leaves monomorphic but fertile leaves generally larger than sterile leaves. Petiole reddish brown at base, becoming green distally, dull but sometimes lustrous at base, 0.5--12 cm, 0.1--1.5 times length of blade; indument of dark brown, narrowly deltate scales at base, of minute, club-shaped hairs distally. Blades highly variable in size and shape, even on 1 plant, narrowly deltate to linear-lanceolate, simple, 1--30 × 0.5--5 cm, leathery, sparsely pubescent, hairs more numerous abaxially than adaxially; blade base cordate, auriculate, or occasionally hastate, auricles rarely attenuate and radicant; margins entire to sinuate, rarely irregularly incised; apex rounded to very long-attenuate and, if attenuate, generally rooting at tip. Rachis green, dull, nearly glabrous. Veins obscure, anastomosing to form areoles near midrib. Sori numerous, scattered somewhat irregularly over blade, often joined at vein junctures. Spores 64 per sporangium. 2 n = 72.
"Rhizome ca 2 mm thick, the scales lance-subulate, entire, dark brown, iridescent; petiole flattened, winged, green except at the dark brown scaly base; blade simple, 5–30 cm, undulate-margined, generally cordate at base with rounded auricles, to 3 cm wide at base, tapering gradually to a flagelliform rooting tip; veins anastomosing, the areoles mostly in 2 rows, the outer veinlets free; 2n=72. Mostly on rocks, esp. limestone; Que. and Ont. to Minn., s. to Ga. and Okla. (Camptosorus r.)"
|Walking fern, doradille ambulante|