Flora of North America species comparison

erect or decumbent, branched mostly from base, not wiry, 15–100 cm.

prostrate to erect, glabrous, smooth or sometimes papillous-scabridulous.

ocrea 4–8 mm, proximal part cylindric, distal part soon disintegrating into curly or straight fibers;

petiole 0–1.5 mm;

blade bluish green, lanceolate or linear-lanceolate, 15–50 × 2–8 mm, margins flat, apex acute;

stem leaves 2.1–4 times as long as branch leaves;

distal leaves abruptly reduced and not overtopping flowers (shorter than or equaling flowers).

cauline, alternate (opposite in P. humifusum), petiolate or sessile;

ocrea with distal part persistent, often hyaline, white or silvery, 2-lobed, chartaceous, glabrous, disintegrating into fibers, or disintegrating completely;

petiole base articulated with ocrea or not;

blade linear, lanceolate, elliptic, ovate, or subround, margins entire.

axillary and terminal, spikelike;

cymes aggregated at tips of stems and branches, 4–6-flowered, bracts inconspicuous.

axillary or axillary and terminal, spikelike, or flowers solitary;

peduncle absent.

enclosed in ocreae, 1–2 mm.

present or absent.

closed;

perianth 1.8–2.4 mm;

tube 10–22% of perianth length;

tepals overlapping, green or white, usually with pink, rarely red or white, margins, petaloid, not keeled, oblong to obovate, cucullate;

midveins usually unbranched;

stamens 7–8.

bisexual, 1–7(–10) per ocreate fascicle, base not stipelike;

perianth nonaccrescent, white or greenish white to pink, campanulate to urceolate, glabrous;

tepals 5, connate 3–70% of their length, petaloid or sepaloid, monomorphic or, rarely, dimorphic, the inner usually flat, the outer flat or sometimes keeled and cucullate distally, sometimes of different length than the inner;

stamens 3–8 (some may be reduced to staminodes);

filaments distinct, free or adnate to perianth tube, glabrous;

anthers whitish yellow, pink to purple or orange-pink, elliptic to oblong;

styles (2–)3, mostly spreading, distinct or connate proximally;

stigmas 2–3, capitate.

enclosed in perianth, brown, ovate, 3-gonous, 1.3–2.3 mm, faces subequal, slightly concave, apex not beaked, with concave edges, shiny, smooth; late-season achenes unknown.

included or exserted, yellow-green, brown, or black, unwinged, (2–)3-gonous, glabrous.

embryo curved.

= 10.