wering
--28.

20b. Calyx-teeth 5, one of them different in size and shape from
the other four (2-6 dm. high; flowers light blue, summer)
=Dragon Head, Dracocephalum parviflorum.=

20c. Calyx-teeth 5, two of them different in size and shape from
the other three --21.

20d. Calyx-teeth 10, subulate (woolly plant 4-10 dm. high, with
whitish flowers in axillary clusters in summer)
=Hoarhound, Marrubium vulgare.=

21a. Corolla deeply split on the upper side and the stamens protruding;
upper lip of the calyx much shorter than the lower (5-10 dm. high;
flowers pink-purple, in terminal spikes, summer) (Wood Sage) --22.

21b. Corolla not deeply split on the upper side --23.

22a. Calyx canescent =Wood Sage, Teucrium canadense.=

22b. Calyx villous =Wood Sage, Teucrium occidentale.=

23a. Flowers in dense terminal head-like spikes, none axillary (1-5 dm.
high; flowers pink-purple or blue, in summer)
=Self-heal, Prunella vulgaris.=

23b. Some or all of the flowers in axillary clusters --24.

24a. Leaves linear, entire (1-4 dm. high; flowers purple, summer)
--25.

24b. Leaves oblong to ovate (summer) --26.

25a. Pedicels shorter than the calyx
=Summer Savory, Satureja hortensis.=

25b. Pedicels much longer than the calyx =Calamint, Satureja glabra.=

26a. Leaves 1 cm. long or less, entire (stems growing in mats, 1-3
dm. long; flowers purple, in summer)
=Wild Thyme, Thymus serpyllum.=

26b. Leaves dentate (flowers purple, summer) --27.

27a. Flowers subtended by bracts as long as the calyx (2-5 dm. high)
=Basil, Satureja vulgaris.=

27b. Flowers with minute bracts or none (1-3 dm. high)
=Basil-thyme, Satureja acinos.=

28a. Corolla 2-lipped or nearly regular, the upper lip flattened,
not conspicuously arched over the stamens --29.

28b. Corolla conspicuously 2-lipped, the stamens ascending under
the concave upper lip --42.

29a. Flowers in dense terminal spikes; corolla 2-lipped (8-15 dm. high;
summer) --30.

29b. Flowers peduncled, 1-4 in the axils of lin