Flora of North America species comparison

shorter than 15 cm, tip mostly rounded;

sheath not winged.

to 3 cm;

tip usually sharp pointed;

sheath winged at base (wing 1–2.5 times as long as wide).

ovaries 1-ovulate, utricular scale with narrow opening at apex.

ovaries 1-ovulate, utricular scale open on 1 side.

0.5–0.6 mm, not winged.

0.5–0.8 mm, not winged.

with 30–60 indistinct ribs, staying within fruit wall after ripening.

with 8–26 distinct ribs, falling out of fruit wall after ripening.

white, small, often decaying.

small, white, often decaying.

floating, 1 or 2–few, coherent in groups, obovate, scarcely gibbous, flat, 1–4 mm, 1–1.5 times as long as wide, margins entire;

veins 3, greatest distance between lateral veins near or distal to above middle;

papillae distinct on midline of upper surface (apical papilla scarcely larger than others);

lower surface often red (more intensely so than on upper), coloring beginning at attachment point of root, upper surface (especially near apex) sometimes with red spots;

air spaces to 0.3 mm;

turions sometimes present, rootless, olive to brown, 0.8–1.6 mm diam., sinking to bottom.

floating, 1 or 2–few, coherent in groups, ovate-lanceolate, flat, 1–6 mm, 1–3 times as long as wide, margins entire;

veins 3, greatest distance between lateral veins near or proximal to middle; 1 often very distinct papilla near apex on upper surface and 1 above node;

anthocyanin absent, no reddish color;

largest air spaces much shorter than 0.3 mm; distinct turions absent.

= 40, 42 (G), 50, 80.

= 40, 42, 50, 60, 80, 84.