1. Polymnia canadensis L. (pale-flowered leaf cup)

Pl. 285 g–i; Map 1212

Plants usually not fragrant when crushed or bruised. Stems 50–180 cm long, moderately to densely pubescent with mostly gland-tipped or sticky hairs toward the tip, glabrous or nearly so toward the base. Leaves sessile or short-petiolate, the larger leaves often with rounded appendages of green tissue at the petiole base, these wrapping around the stem, the appendages of the adjacent leaves at a given node sometimes more or less fused into a short cup around the stem. Leaf blades 3–40 cm long, mostly broadly tapered at the base, mostly with 3–7 more or less pinnate lobes (the smaller, upper leaves sometimes unlobed), the lobes tapered to a sharply pointed tip, the margins otherwise finely to coarsely toothed, the surfaces glabrous or sparsely to moderately pubescent with more or less spreading, sometimes somewhat sticky or gland-tipped hairs, especially along the veins. Involucre 5–9 mm long, 6–13 mm in diameter, the bracts moderately to densely pubescent with sticky or gland-tipped hairs on the outer surface. Outer series of 2–4 involucral bracts somewhat longer and narrower than the others, lanceolate to narrowly ovate, the inner series ovate to broadly obovate. Ray florets (4)5, the corolla reduced to a minute tube and lacking a ligule or with a short, broad ligule 2–10 mm long. Disc florets 26–40, the corolla 3–4 mm long. Fruits with 3 blunt angles or less commonly ribs, dark brown to black, usually with some reddish brown mottling. 2n=30. May–October.

Scattered in the Ozark and Ozark Border Divisions and in some additional counties bordering the Mississippi and Missouri Rivers (eastern U.S. west to Minnesota and Oklahoma; Canada). Bottomland forests, mesic upland forests in ravines, bases and ledges of bluffs, and banks of streams and rivers; also fencerows, pastures, railroads, and roadsides.

This species frequently occurs in large colonies along stream terraces and also is a characteristic component of the vegetation along moist, shaded talus areas at the bases of steep, rocky slopes or bluffs. The form with relatively well-developed ray corollas has been called f. radiata (A. Gray) Fassett and is about as common as the nearly rayless form.