Flora of North America species comparison

single, terete, 2.5–8(–10) dm, branching all or mostly alternate.

4-angled with wings to 0.2 mm wide, branching alternate or proximal rarely opposite.

basal and cauline usually present at flowering time;

basal blades oblanceolate to spatulate, 4–10 cm × 9–25 mm;

cauline blades abruptly differentiated, linear to lanceolate, 1.5–5(–6.5) cm × 1–8(–15) mm.

all cauline at flowering time;

blade linear to narrowly lanceolate, 0.7–3 cm × 1–4.5(–6) mm.

flowers solitary or paired at ends of branches;

pedicels (30–)80–120 mm.

open cymes;

pedicels (2–)10–40 mm.

8–12(–14)-merous;

calyx tube shallowly campanulate, (2–)3–4(–8) mm, mid- and commissural veins about equally prominent, not ridged;

lobes narrowly linear to subulate, 4–20 mm;

corolla pink or rarely white, eye yellow, projections of eye into corolla lobes oblong, usually with a red border, tube 5–9 mm, lobes narrowly spatulate-obovate, 16–35 × 5–12 mm, apex rounded to obtuse;

anthers coiling circinately.

5-merous;

calyx tube campanulate, 2.8–5.5 mm, commissural veins more prominent than midveins, ridged, lobes linear, 9–13 mm;

corolla purplish pink or rarely white, eye yellow or yellowish green, projections of eye into corolla tube oblong to narrowly triangular, alternating with shorter white or paler yellow zones, tube 3–7 mm, lobes narrowly spatulate-obovate, 8–18 × 3–6 mm, apex rounded;

anthers coiling circinately.

 = 36.