Flora of North America species comparison

internodes 2–4-lined at first, then 2-winged.

internodes 4-lined at first, eventually 2-lined.

blades usually oblong to elliptic, rarely obovate to oblanceolate or triangular-ovate, 12–36 × 6–16 mm, base articulated, rounded to slightly cordate-amplexicaul, without glandlike auricles, margins plane to subrecurved, apex rounded to obtuse, midrib with to 3 pairs of branches.

blades narrowly oblong or oblanceolate to linear, 5–15 × 1–3 mm, base not articulated, rounded to cuneate, margins recurved to subrevolute, apex rounded to obtuse, midrib with 1–3 pairs of branches.

± narrowly cylindric to narrowly pyramidal, 1–3(–7)-flowered, branching dichasial, from to 4 proximal nodes.

rounded-pyramidal, 1–3-flowered, narrowly branched, sometimes with 1–3-flowered dichasia or branches from to 4 proximal nodes.

20–30 mm diam.;

sepals persistent, enclosing capsule, 4, unequal, outer broadly ovate to circular, 9–20 × 9–18 mm, apex apiculate or obtuse to rounded, inner narrowly elliptic to lanceolate, 7–14 × 2–4 mm, apex acute to subacute;

petals 4, bright yellow, obovate, 11–18 mm;

stamens persistent, 80–100;

ovary 3(–4)-merous.

15–25 mm diam.;

sepals persistent, not enclosing capsule, (3–)4(–5), oblong or elliptic-oblong to linear, subequal or equal, 3–5 × 1–1.4 mm;

petals (3–)4(–5), bright yellow, obovate (larger pair) to obovate-oblong (smaller pair), 10–12 mm;

stamens persistent, 60–70;

ovary 3-merous, placentation parietal.

narrowly ellipsoid-ovoid, 7–10 × 5–6.5 mm.

cylindric-ellipsoid to narrowly ovoid-conic, 6–8 × 2.5 mm.

not carinate, 0.8 mm;

testa shallowly scalariform.

not carinate, 0.9–1 mm;

testa linear-foveolate.

= 18.

= 18.