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 7 pairs, usually remote, horizontal, distance between 1st and 2d pinnae not or slightly more than between 2d and 3d pairs, undivided except in proximal 2/3–1/2.

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.

stalk 4–20 cm, 2–2.5 times length of trophophore rachis;

blade green to dark green, plane, 2–3-pinnate, to 18 × 28 cm, herbaceous.

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

elongate, obliquely lanceolate to narrowly lanceolate, margins nearly parallel and finely denticulate, apex short-acuminate, venation pinnate.

1–2-pinnate, 2–3 times length of trophophore.

pinnately branched or simple.

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

=90.