Flora of North America species comparison

prostrate, branched, 3–5 dm, pilose and glandular-pilose, or with sessile glands.

erect, 2.3–5.2 dm, sparsely pubescent with short hairs, these rarely with gland heads.

aromatic;

petiole 0.7–1 cm;

blade ovate or elliptic, 1.3–2.1 × 1.1–1.5 cm, reduced somewhat in inflorescence, base cuneate, apex obtuse, glandular-pubescent.

aromatic;

petiole to 1.3 mm;

blade 1.7–4.5 × 0.7–2.6 cm, base cuneate, margins pinnatifid or entire (in distal leaves), apex acute to acuminate, mucronate, with sessile glands adaxially.

axillary glomerules;

glomerules subglobose, 4–6 mm diam.;

bracts similar to cauline leaves, elliptic, reduced to 0.8 mm, margins crenate-dentate, apex obtuse.

terminal compound cymes, 8.5–22 cm;

bracts leaflike, lanceolate, 2.1–10.3 × 0.1–0.6 mm, generally absent in fruit.

perianth segments 5, distinct nearly to base, distinct portions elliptic to oblong, strongly keeled, 1.8–1.9 × 0.3–0.5 mm, apex acuminate, fimbriate and hirsute, pubescent with septate hairs, hardly enclosing fruit, becoming white, strongly crested and 5-winged vertically, rostrate, semiorbiculate, and cartilaginous in fruit;

stamen 1;

stigmas 2.

perianth segments 5, distinct nearly to base, distinct portion ovate, with large single tubercle abaxially near apex, 0.5–0.7 × 0.35–0.6 mm, apex acuminate, with sessile golden glands, covering seed at maturity;

stamens 1(–2);

stigmas 2.

ovoid;

pericarp adherent, membranaceous, slightly rugose and papillate.

subglobose;

pericarp adherent, membranaceous, papillose, becoming rugose, usually white-blotchy.

reddish brown, ovoid, 0.6–0.7 × 0.5–0.6 mm, margins slightly keeled over radicle and grooved over cotyledons;

seed coat smooth.

subglobose, 0.6–0.9 × 0.5–0.7 mm, margins rimmed;

seed coat rugose.