Flora of North America species comparison

lacking root hairs, unbranched or with a few narrow lateral branches, in 1 species dichotomously branched.

simple, unbranched, upright, with eustelic vascular tissue.

bases dilated, clasping, forming sheath, open or fused, surrounding successive leaf primordia;

primordia glabrous or with long, uniseriate hairs.

to 12 pairs, usually approximate to overlapping, slightly ascending, distance between 1st and 2d pinnae not or slightly more than between 2d and 3d pairs, lanceolate, divided to tip.

exposed or embedded, 0.5–1.5 mm diam., thick-walled, with thousands of spores.

all 1 kind, trilete, thick-walled, surface rugate, tuberculate, baculate (with projecting rods usually higher than wide), sometimes joined in delicate network, mostly with ± warty surface.

not green, usually fleshy, round or linear, subterranean, mycorrhizal.

sessile;

blade pale green, 3–4-pinnate, to 25 × 33 cm, thin, herbaceous.

blades compound to simple, rarely absent, veins anastomosing or free, pinnate, or arranged like ribs of fan.

lanceolate and deeply lobed, lobes linear, serrate, apex pointed, venation pinnate, midrib present.

2-pinnate, 0.5–1.5(–2) times length of trophophore.

pinnately branched or simple.

absent or of widely scattered, long, uniseriate hairs, especially on petioles and rachises.

=184.