Flora of North America species comparison

never tuberous.

erect to reclining, not rooting nodally, hirsute or sometimes pilose or glabrous, base not bulbous.

floating or prostrate, glabrous, rooting at proximal nodes.

basal leaves seldom present, cauline leaf blades semicircular to reniform, 1-6x-lobed, parted, or dissected 1.2-7.3 × 1.9-10.8 cm, base truncate or cordate, segment margins entire or crenate, apex rounded to filiform.

broadly ovate to semicircular or reniform in outline, 3-parted or -foliolate, 1.5-5.3 × 2.2-8 cm, segments usually again 1(-2)×-lobed, ultimate segments oblong or elliptic to lanceolate or oblanceolate, margins dentate (sometimes dentate-lobulate or entire), apex acute to rounded-obtuse.

receptacle glabrous;

sepals reflexed 2-3 mm above base, 4-7(-9) × 2-4 mm, hirsute;

petals 5-14, yellow, 5-13 × 1.5-8 mm.

receptacle sparsely hispid;

sepals 5, spreading or weakly reflexed, 5-7 × 3-6 mm, glabrous;

petals 5-6(-14), 7-12 × 5-9 mm;

nectary scale variable, crescent-shaped, funnel-shaped, or flaplike;

style 0.8-1.2 mm.

hemispheric, 3-7 × 5-9 mm;

achenes 2.6-3.6(-4.8) × 1.8-3(-3.2) mm, glabrous, rarely hispid, margin forming narrow rib 0.1-0.2 mm wide;

beak persistent, lanceolate to lance-subulate, straight or curved, 0.4-2.2 mm.

ovoid, 8-10 × 7-8 mm;

achenes 1.8-2.2 × 1.6-2.2 mm, glabrous;

beak lanceolate, straight, 1-1.8 mm.

= 32.