Annual or perennial herbs. Flowers bisexual, in 2-many-flowered verticils, (in ours) arranged compactly to form an uninterrupted terminal spike. Calyx of 5 subequal lobes; not 2-lipped. Corolla 2-lipped; upper lip obsolete, very short; lower lip conspicuous and 3-lobed; tube exserted from the calyx. Perfect stamens 4. Filaments not basally connate. Ovary shallowly 4-lobed. Nutlets reticulate.