Stem 2–4.5 dm, rather stout, purple or magenta; infl 5–20 cm, with 7–25 fls; sep and lateral pet arching forward, lance-oblong, 8–15 mm, yellowish-white with 3–5 conspicuous longitudinal purple stripes, also purple-margined; lip declined, 8–12 mm, white, heavily striped with purple, or wholly purple. Woods; N.B. and s. Que. to B.C., s. Mich., Wis., Minn., N.D., and in the w. cordillera to Mex. May–July.