Flora of North America species comparison

emersed;

petiole triangular, erect to ascending, 6.5–51 cm;

blade sagittate, rarely hastate, 1.5–30.5 × 2–17 cm, basal lobes equal to or less than remainder of blade.

submersed, phyllodial, lenticular, to nearly terete, 12–53 × 0.3–0.7 cm;

rare stranded plants without expanded leaf blades.

racemes, rarely panicles, of 3–9 whorls, emersed, 4.5–28.5 × 4–23 cm;

peduncles 10–59 cm;

bracts connate more than or equal to ¼ total length, elliptic to lanceolate, 3–8 mm, delicate, not papillose; fruiting pedicels spreading, cylindric, 0.5–3.5 cm.

racemes, of 2–7 whorls, floating or emersed, to 16 × 4 cm;

peduncles 13.5–28 cm;

bracts connate more than ¼ total length, ovate to lanceolate, 1.5–2 mm, delicate, not papillose; fruiting pedicels spreading to reflexed in flower and fruit, cylindric, 1.5–6.5 cm.

to 4 cm diam.;

sepals recurved to spreading, not enclosing flower or fruiting head;

filaments cylindric, longer than anthers, glabrous; pistillate pedicellate, without ring of sterile stamens.

1.5–5 cm diam.;

sepals spreading in staminate, appressed to spreading in flower and fruit in pistillate, often enclosing flower or fruiting head;

filaments dilated, longer than anthers, glabrous; pistillate pedicellate, without ring of sterile stamens.

heads 1–1.7 cm diam;

achenes oblanceoloid, without abaxial keel, 2.5–3.5 × to 2 mm, beaked;

faces not tuberculate, wings absent, glands (0–)1(–2);

beak lateral, horizontal, 1–2 mm.

heads 0.4–0.6 cm diam;

achenes oblanceoloid to obovoid, not abaxially keeled, 1.5 × 1 mm, beaked;

faces not tuberculate, wings absent, glands absent;

beak lateral, erect, 1.1 mm.

= 22.