Fls not resupinate, the lip uppermost; lateral sep inequilateral; lateral pet arising from near the middle of the column, strongly inequilateral, directed forward, cohering at the tip; lip clawed, the broad blade folded and at first embracing the column; anther subterminal, with 4 pollinia; rhizomatous perennials with a cluster of basal lvs and an erect scape bearing a few narrow scales and a terminal raceme. 25, warm Amer.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.