Trillium sessile L.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Rhizome very thick and stout; stem 1–3 dm at anthesis; lvs broadly ovate to rotund, sessile, rounded, broadly obtuse or obscurely cuspidate, usually only inconspicuously or not at all mottled, seldom over 9 cm at anthesis; fl sessile, foetid; sep spreading or ascending, lance-ovate, 2–3 cm; pet normally maroon (yellow or green), ascending, narrowly to broadly elliptic, narrowed to a sessile base, equaling or slightly longer than the sep and twice as long as the stamens; filaments (2–)3–4(–5) mm, less than half as long as the introrse anthers, the flattened connective with a prolongation nearly as long as the filament; stigmas 1.5–2 times as long as the subglobose, sharply 6-angled or -winged ovary; 2n=10. Rich moist woods; w. Pa. and sw. N.Y. to s. Mich., Ill., Mo., and e. Kans., s. to Md., Va., n. N.C., n. Ala., and n. Ark. Apr., May.