Flora of North America species comparison

alternate;

stipular glands very inconspicuous, present at proximal nodes, absent distally;

blade linear or narrowly oblong, 10–13(–20) × 2–2.5 mm, base flat, not clasping, margins without stalked glands.

alternate;

stipular glands present at proximal nodes, usually absent distally;

blade threadlike to linear, 15–20(–30) × 1–1.5 mm, base flat, not clasping, margins without stalked glands.

cymes monochasial (scorpioid or helicoid), open, branches unequal (main axis obvious), internodes long, flowers widely scattered;

bract margins without prominent glands.

cymes dichasial, open, internodes long, flowers widely scattered;

bract margins without prominent glands.

5–25 mm, scarcely longer in fruit, spreading at angles 70–80(–90)°, scarcely bent at apex.

(2–)10–12 mm, to 40 mm in fruit, spreading at 45–90° angle, not or only slightly bent at apex.

sepals erect or reflexed at tip, lanceolate, 1.5–2.5 mm, usually equal, sometimes one larger, marginal glands absent or minute, surfaces glabrous;

petals not or slightly spreading at anthesis, yellow, often with reddish or orange streak on midvein, oblanceolate, sometimes obovate, 0.5–2.5(–4) mm, apex notched or erose;

cup yellow, rim with petal attachment protruding prominently in sinus or strongly indented;

stamens included;

filaments 1–2 mm;

anthers yellow, dehisced anthers 0.5–0.8(–1.2) mm;

ovary chambers 6;

styles 3, yellow, 0.5–1(–1.8) mm, included.

sepals all or outer 2 spreading, not reflexed at tip, lanceolate, 1.5–2(–3) mm, ± equal, marginal glands minute or absent, surfaces glabrous;

petals horizontally widely spreading, bright yellow fading white, tinged with orange or red along veins, oblanceolate to obovate, (2–)3–4 mm, apex acute or apiculate;

cup yellow, rim lobed between filaments and petal attachments;

stamens exserted;

filaments 2–3(–3.5) mm;

anthers yellow, dehisced anthers 1.2–1.5 mm;

ovary chambers 4;

styles 2(–3), yellow, 2–3.5 mm, exserted.

= 36.

= 34.