Flora of North America species comparison

erect to ascending, 1–30(–40) cm, glandular- or eglandular-hairy.

erect, rarely ascending, (15–)30–70(–100) cm, eglandular-hairy, hairs evenly distributed around stem.

in 3–6 pairs per stem;

blade oblong to broadly ovate, (2–)5–14(–35) × (2–)3–10(–18) mm, 2.5 times as long as wide, base truncate, margins crenate-serrate, apex obtuse to rounded, surfaces sparsely eglandular-hairy, rarely also glandular-hairy.

blade ovate or oblong-ovate, rarely lanceolate, (20–)30–55(–70) × (6–)15–25(–45) mm, 2–3(–4) times as long as wide, base ± cordate, margins dentate to serrate to crenate-incised, rarely subentire, apex acute, abaxial surface hairy, adaxial glabrous.

1(–3), terminal, 20–150 mm, (5–)15–40(–60)-flowered, axis densely eglandular- and glandular-hairy;

bracts linear-oblong, (3.5–)4–6(–10) mm.

2–4(–8), axillary, 60–150 mm, 50–150-flowered, axis hairy;

bracts linear-lanceolate to linear, 4–8(–14) mm.

erect, 0–4 mm, shorter than subtending bract, densely eglandular- and glandular-hairy.

erect, 3–7(–14) mm, equal to subtending bract, eglandular-hairy.

calyx lobes (2–)3.5–5(–6) mm, 0.8–2 mm wide, apex acute, glandular-hairy;

corolla sky blue to intense blue, 2–4 mm diam.;

stamens 0.3–0.5 mm;

style (0.2–)0.4–0.6(–1) mm.

calyx 5-lobed, abaxial lobes 3–4 mm, adaxial 1–1.5 mm, apex acute, glabrous or hairy;

corolla bright blue, rarely pinkish or white, (9–)12–18 mm diam.;

stamens 4.5–6 mm;

style 5–6 mm.

compressed in cross section, obcordiform, 2–4 × 2.5–5 mm, apex markedly emarginate, glandular-ciliate, otherwise glabrous.

± compressed to ± round in cross section, broadly obovoid or obcordiform, (3–)4–5.5 × (2.5–)3.5–5 mm, apex not deeply, narrowly emarginate, glabrous or sparsely hairy.

10–30, yellowish, ovoid, flat, 0.7–1.7 × 0.4–1 mm, 0.2–0.4 mm thick, rugose.

(2–)8–18, brown, widely ellipsoid to widely obovoid, flat, 1.2–2.1 × 1–1.5 mm, 0.2–0.4 mm thick, smooth.

= 16.

= 48, 64 (Europe).