Glabrous perennial 2-8 dm; lfls of the principal lvs mostly 19-31, oblong to elliptic, mostly flat, 5-10 mm; spikes very dense, ovoid, becoming cylindric and 2-5 cm; bracts slender, caudate-acuminate, surpassing the cal, which is flanked at the base by a pair of bracteoles; fls of sect. Kuhnistera, 5-6 mm, rose-purple (white); cal-tube 10-angled, glabrous, the short teeth densely hairy within; 2n=14. Cedar glades and calcareous barrens; c. Tenn. to n. Ala.; also on bluffs and stony flats along the upper Illinois R. and tributaries in ne. Ill. July. (Petalostemon f.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.