Erythronium mesochoreum Knerr
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Much like no. 3 [Erythronium albidum Nutt.], but scarcely colonial, the sterile corms without offshoots, producing a new corm at the base of the old; lvs conduplicate, not mottled; tep spreading or slightly reflexed at anthesis; mature peduncles recurved, the fr resting on the ground, depressed at the summit; 2n=22. Prairies, pastures, and dry open woods; Io., w. Ill., and e. Nebr. to Ark., Okla., and Tex. Mar., Apr.