Cal 10-13-nerved, 2-lipped, the tube densely villous in the throat, the lips about equaling the tube and each other, the lower lip bifid to the base, the upper much wider, 3-lobed to the middle with triangular upturned lobes; cor 2-lipped, the upper lip flat or nearly so, straight, broadly rounded, the lower lip spreading, slightly the longer, its 3 lobes subequal; stamens 4, straight, exsert, subequal; shrubs or half-shrubs with small lvs and small blue, purple, or white fls in axillary clusters often aggregated into a loose terminal spike- like infl. 50+, temp. Eurasia.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.