PLANT: Annual herbs; stems 6 35 cm tall. LEAVES: subsessile; blades 13 36 mm long, 2 7 mm wide, linear to narrowly oblong to elliptic, 3 nerved; margins entire. FLOWERS: pedicels 0.5 1.5( 5) mm long; calyx actinomorphic, 3 6 mm long; corolla 4 5 mm long, the tube included, white except the middle lobe of the lower lip pink purple; stamens only slightly exceeding corolla, the filaments blue, the anther sacs slightly divaricate. NUTLETS: ca. 2.5 mm long, dark brown to greenish tan, the apex with a few short curled hairs. 2n = 14. NOTES: Mesquite scrub to pine oak woodland, often in riparian zones: Gila, Yavapai cos.; 1150 1650 m (3800-5400 ft); Jul Oct; s Can to n FL, c TX, w NE. Kearney et al. (1960) report this species in Cochise Co. and Lewis (1945) reports it in extreme s Navajo Co., but neither cite a specimen nor a more precise locality. REFERENCES: Christy, Charlotte M., et. al. 2003. Lamiaceae. J. Ariz. - Nev. Acad. Sci. Volume 35(2).
From Flora of Indiana (1940) by Charles C. Deam
My specimens, supplemented by reports from 6 other counties made by other authors, show that this species is an infrequent to rare plant throughout the state. It may, however, be more frequent than our records indicate because it closely resembles the common pennyroyal and may not be distinguished easily. It is generally found in bare, gravelly or sandy places about gravel pits, in old lake beds, along roadsides and railroads, washed places in fallow fields, and on open, wooded slopes. Usually common in large colonies where it is found.
Stems much branched, 2-4 dm, finely puberulent, glandular in the infl; lvs short-petioled, mostly elliptic to lanceolate, usually 3-nerved, acute; pedicels to 1 cm; cal-lobes 2-3 mm, in fr 3-5 mm; cor blue, the oblong lobes 1.5-2 mm; nutlets 2.5-3 mm, puberulent at the top. Dry soil; Vt. and Ont. to Minn. and Nebr., s. to Fla. and Ariz. Aug., Sept. (Trichostema b.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.