Lycopus L.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1972, Flora Europaea. Volume 3. Diapensiacea to Myoporaceae, Cambridge: Cambridge University Press : 183

34. Lycopus L. 1

Perennial, odourless herbs with creeping rhizome. Verticillasters many-flowered, dense, distant. Calyx campanulate, 13-veined, with 5 equal teeth. Corolla-tube shorter than calyx, with 4 subequal lobes, the uppermost usually wider than others. Stamens 2, exceeding corolla; staminodes 0 or 2. Leaves pinnatifid or pinnatisect at base, toothed or shallowly lobed at apex; bracts 3-5 mm; calyx-teeth c. 2 mm, spiny; staminodes minute or absent 1. europaeus Leaves pinnatifid or pinnatisect to the apex; bracts 6-9 mm; calyxteeth c. 1-5 mm, not spiny; staminodes conspicuous, capitate

2. exaltatus