Flora of North America species comparison

creeping or floating, rooting nodally, glabrous, not bulbous-based.

erect or reclining, hispid or sometimes glabrous.

linear to obovate, undivided or 3-lobed, 1.5-3.6 × 0.3-2 cm, lobes lanceolate or elliptic, margins entire, apex rounded to acuminate.

receptacle glabrous;

sepals spreading, 6-10 × 4-7 mm, glabrous;

petals 7-11, white or pink, 8-13 × 3-6 mm.

pedicellate;

receptacle hispid;

sepals 5, reflexed, 3-4 × 2 mm, sparsely hispid;

petals 5, 4-5 × 2-3 mm.

globose or hemispheric, 5-12 × 9-15 mm;

achenes 4.2-5.2 × 2.4-3.2 mm, glabrous;

beak persistent, lanceolate, straight or curved, 1-1.2 mm.

ovoid, 8-9 × 6-7 mm;

achenes 30-60 per head, 2 × 2 mm, faces densely tuberculate, glabrous, margin smooth;

beak semicircular, hooked, 0.3 mm.

roots absent.

and lower cauline leaf blades cordate-ovate, 3-foliolate, 5-8 × 3-6(-7) cm, leaflets again cleft or parted, leaflet base obtuse to acute, margins dentate, apex rounded to acute.

= 32.