Flora of North America species comparison

not aromatic, indistinctly or abruptly petiolate;

petiole winged;

blade with deep reticulate veins abaxially, ovate to ovate-oblong, 5–20 × 2–6 cm, thin, membranaceous in age, margins coarsely toothed, apex acute to obtuse, surfaces pubescent, hairs simple.

not aromatic, indistinctly petiolate;

petiole broadly winged;

blade without deep reticulate veins abaxially, spatulate, 8–15 × 2 cm, thin, margins irregularly and sharply dentate to sinuate-dentate, apex obtuse to acute, surfaces glabrous.

5–16-flowered;

involucral bracts plane, unequal.

(6–)10–25-flowered;

involucral bracts plane, ± equal.

erect to drooping, moderately thick, 3–20 mm, length 1–3 times bracts, flexuous.

erect, thin, 10–30 mm, length 2–5 times bracts, flexuous.

heterostylous;

calyx pale green, broadly campanulate, 0.8–2 cm;

corolla yellow, with orange spots at base of lobes, tube 8–20 mm, length to 1 times calyx, eglandular, limb 8–28 mm diam., lobes 8–14 mm, apex slightly emarginate to distinctly notched.

heterostylous;

calyx green, campanulate, 3–5 mm;

corolla lavender, tube 8–10 mm, length 2 times calyx, eglandular, limb 10–16 mm diam., lobes 5–8 mm, apex emarginate.

ovoid, length to 1 times calyx.

ellipsoid, length 1–2 times calyx.

without flanged edges, minutely vesiculate.

without flanged edges, reticulate.

= 22 (Europe).

= 18.