Flora of North America species comparison

to 15 cm, tip mostly rounded;

sheath not winged.

to 3.5 cm, tip usually sharp pointed;

sheath narrowly winged at base (wing 2–3 times as long as wide).

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

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

0.8–1 mm, laterally winged toward apex.

0.7–1 mm, not winged.

with 8–15 distinct ribs, staying within fruit wall after ripening.

with 35–70 indistinct ribs, staying within fruit wall after ripening.

white, small, often decaying.

white, small, often decaying.

floating, 1 or 2–5 or more, coherent in groups, ovate, scarcely gibbous, flat, 1–8 mm, 1.3–2 times as long as wide, margins entire;

veins 3(–5) (if more than 3, outer ones branching from inner ones), greatest distance between lateral veins near or proximal to middle;

papillae not always distinct (one near apex usually larger);

lower surface very seldom slightly reddish (much less than on upper), coloring beginning from attachment point of root, upper surface occasionally diffusely reddish;

air spaces 0.3 mm or shorter; distinct turions absent.

floating, 1 or 2–few, coherent in groups, ovate-obovate, flat, 1–4 mm, 1–1.7 times as long as wide, margins entire;

veins 3, greatest distance between lateral veins near or distal to middle; 1 distinct papilla near apex on upper surface, 2–3 very distinct papillae above node;

anthocyanin absent, no reddish color;

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

= 40, 42 (B), 50, 63, 126.

= 40 (U), 42 (G).