This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Perennial herbs (some tropical species woody), with opposite membranous lobed or angled leaves, or the lower alternate, and mostly large corymbose-paniculate heads of both tubular and radiate yellow or whitish flowers, or rays sometimes wanting. Involucre hemispheric or broader, of about 5 large outer bracts, and more numerous smaller inner ones. Receptacle chaffy. Ray-flowers pistillate, fertile, subtended by the inner involucral bracts, the ligules elongated, minute, or none. Disk-flowers subtended by the chaffy scales of the receptacle, perfect, sterile, their corollas tubular, 5-toothed. Anthers 2-toothed at the base. Pappus none. Achenes thick, short, turgid, glabrous. [From the Muse Polhymnia.)
About 10 species, natives of America. Only the following are known in North America. Type species: Polymnia canadensis L. Rays commonly 6" long or more, yellow; achenes strongly striate.
1. P. Uvedalia.
Rays commonly minute or up to 6 long, whitish, or none; achenes 3-ribbed.
2. P. canadensis.
Polymnia Uvedalia L. Sp. Pl. Ed. 2, 1303. 1763.
Rough-pubescent, stout, branched, 3°-10° high. Leaves broadly ovate or deltoid, 3-nerved, abruptly contracted above the base, minutely ciliate, more or less pubescent on both sides, angulate-lobed, the lower often 1° long and broad, petioled, the upper sessile, somewhat clasping; heads few in terminal clusters, peduncled, 11/2'-3' broad; rays 10-15, commonly 6"-12" long, linear-oblong, bright yellow, 3-toothed or entire; exterior bracts of the cup-like involucre ovate-oblong, obtuse, ciliate, 4"-10" long; achenes slightly oblique and laterally compressed, strongly striate, nearly 3" long.
In rich woods, New York to Indiana, Florida, Missouri, Oklahoma and Texas. Bermuda. Yellow bears-foot. July-Aug.
Polymnia canadensis L. Sp. Pl. 926. 1753. Polymnia canadensis radiata A. Gray, Syn. Fl. N. A.
1: Part 2, 238. 1884. P. radiata Small, Fl. S.E. U. S. 1239. 1903.
Rather slender, viscid-pubescent, at least above, simple or branched, 2°-5° high. Leaves deltoid-ovate to hastate, usually very thin, all petioled, deeply angulate-lobed and the lobes dentate, or the lower lyrate-pinnatifid, 4'-10' long, the uppermost sometimes ovate and entire or merely denticulate; heads few in terminal clusters, short-peduncled or sessile, 4,"-6" broad; outer bracts of the involucre ovate to lanceolate, obtuse or acutish, 2"-3" long; rays small, minute or none, or sometimes up to 6" long and 3-lobed, whitish or yellowish; achenes 3-angled, obovoid, obcom-pressed, 3-ribbed, not striate.
In damp, rich shaded places, Vermont and Ontario to Minnesota, Pennsylvania, North Carolina, Tennessee and Arkansas. June-Sept.