Flora of North America species comparison

petiole 0–1 mm;

blade usually elliptic, sometimes falcate, without marked size dimorphism, to 42 × 5 mm, base acute, margins entire, apex rounded to acute.

petiole 0.5–3.5 mm;

blade ovate to elliptic, without marked size dimorphism, to 40 × 30 mm, base acute to rounded, margins usually crenate to serrate, sometimes small leaves entire, apex acute.

60-flowered.

35–65-flowered.

± radially symmetric;

petals spatulate, 5 mm, claws distinct;

stamens exserted distally (not laterally between petal claws).

strongly bilaterally symmetric;

petals spatulate, 10–15 mm, claws postgenitally distally coherent, forming slitted corolla tube;

stamens exserted laterally through slits between petal claws.

= 46.

= 46.