Flora of North America species comparison

not proliferous.

not proliferous.

short-creeping or ascending, frequently branched;

scales dark reddish brown to blackish throughout, narrowly deltate, 2–4 × 0.2–0.4 mm, margins entire to undulate or with widely spaced shallow teeth.

erect or ascending, usually unbranched;

scales dark brown throughout, narrowly deltate, 2–3 × (0.2–)0.5–1 mm, margins entire.

monomorphic.

monomorphic but fertile leaves generally larger than sterile leaves.

reddish brown at base, green distally, lustrous, 1–5(–6) cm, 1/4–1/2(–1) times length of blade;

indument of dark reddish brown to black, narrowly deltate scales grading into glandular hairs.

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.

linear, 1-pinnate throughout, 2–13 × 0.6–1.2 cm, thin, glabrous or with sparse minute hairs;

base slightly tapering or truncate;

apex acute, not rooting.

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.

in 6–21 pairs, deltate to rhombic;

medial pinnae 5–6 × 4–5 mm;

base obtuse and often inequilateral;

distal margins crenate;

apex rounded to acute.

free, evident.

obscure, anastomosing to form areoles near midrib.

2–4 pairs per pinna, on both basiscopic and acroscopic sides.

numerous, scattered somewhat irregularly over blade, often joined at vein junctures.

64 per sporangium.

64 per sporangium.

green throughout, dull, glabrous or with scattered hairs as on petioles.

green, dull, nearly glabrous.

= 72.

= 72.