Rhizomatous, clonal, erect perennial to 15 dm, with 7–15 nodes below the infl; lvs crenate or repand to seldom entire or sharply toothed; lowest 4–9 pairs of lvs petiolate and often persistent, the petiole to 6 cm, the blade 3–10 × 1–3 cm and mostly tapering at base; middle and upper lvs sessile, mostly widest at or below the middle (but generally not at the base), at least some of them clasping; floral bracts abruptly smaller than the upper leaves; raceme-axis minutely puberulent; fls loosely spaced; cal-tube 3.5–6 mm at anthesis, often glandular-punctate but not stipitate-glandular; cor (14–)16–30 mm, densely puberulent to subglabrous; 2n=76. Wooded riverine swamps and fresh or brackish marshes on the coastal plain, often in deep shade; se. Va. to Fla. July–Sept. (P. aboriginorum; P. denticulata, misapplied) Closely allied to the diploid (2n=38) P. purpurea (Walter) S. F. Blake, also of the coastal plain but extending n. only to N.C. and usually found in sunnier habitats, which has the upper lvs more reduced, and the principal lvs widest at or above the middle.
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