Perennial, erect, quadrangular, glabrous, strongly scented, tomentose herbs, 30-50 cm high; rootstock creeping; stem reddish green with robust or slender, ascending, glabrous branches; leaves opposite, ovate-elliptic-oblong, subacute, serrate, glabrous above, hoary beneath; flowers small, sessile, arranged in terminal, interrupted verticillasters or spikes, 5-7 cm long; pedicels very short, hairy; bracts-bracteoles small; calyx tubular or campanulate, 10 nerved; limb subequally 5-toothed or sub-bilabiate, throat naked or villous; corolla liliac, tubular, limbs-4, somewhat irrequalar, posterior lobes larger, entire or emarginate, glabrous within; stamens-4, equal, erect, exserted, anthers cells-2, distinct, parallel; disc symmetrical, style arms short, stigma 2-fid; nutlets ovoid, smooth, pale brown.