8. Lycopus. Fertile stamens 2, and often 2 sterile filaments without anthers.

[+][+] Corolla more or less 2-lipped.

[++] Stamens distant and straight, often divergent, never convergent nor curved.

[=] Stamens 2, with or without rudiments of the upper pair.

9. Cunila. Calyx very hairy in the throat, equally 5-toothed. Corolla small.

[=][=] Stamens 4, calyx 10--13-nerved, and hairy in the throat (except n. 10).

10. Hyssopus. Calyx tubular, 15-nerved, equally 5-toothed. Stamens exserted.

11. Pycnanthemum. Calyx ovate or short-tubular, equally 5-toothed or somewhat 2-lipped. Flowers in dense heads or cl.u.s.ters.

12. Origanum. Calyx ovate-bell-shaped, 5-toothed. Spikes with large colored bracts.

13. Thymus. Calyx ovate, nodding in fruit, 2-lipped. Bracts minute; leaves very small.

[++][++] Stamens (often 2 only in n. 16) ascending or arcuate, often more or less converging (or ascending parallel under the erect upper lip in n. 14 and 15).

14. Satureia. Calyx bell-shaped, 10-nerved, naked in the throat, equally 5-toothed.

15. Calamintha. Calyx tubular, often hairy in the throat, 13-nerved, 2-lipped. Tube of corolla straight.

16. Melissa. Calyx tubular-bell-shaped, flattish on the upper side.

Corolla curved upward.

17. Hedeoma. Calyx gibbous on the lower side, hairy in the throat.

Flowers loose.

Tribe III. MONARDEae. Stamens 2, ascending and parallel; anthers apparently or really 1-celled. Corolla strongly 2-lipped.

18. Salvia. Calyx 2-lipped. Anthers with a long connective astride the filament, bearing a linear cell at the upper end, and none or an imperfect cell on the lower.

19. Monarda. Calyx tubular and elongated, equally 5-toothed. Anthers of 2 cells confluent into one, the connective inconspicuous.

20. Blephilia. Calyx ovate-tubular, 2-lipped. Anthers as in the last.

Tribe IV. NEPETEae. Stamens 4, the upper (inner) pair longer than the lower, ascending or diverging. Corolla 2-lipped; the upper lip concave or arched, the lower spreading. Calyx mostly 15-nerved.

[*] Anthers not approximate in pairs; their cells parallel or nearly so.

21. Lophanthus. Stamens divergent, exserted; upper pair declined, lower ascending.

22. Cedronella. Stamens all ascending, not exceeding the lip of the corolla.

[*][*] Anthers more or less approximate in pairs; their cells divaricate or divergent; filaments ascending, not exserted.

23. Nepeta. Calyx more or less curved, equally 5-toothed.

24. Dracocephalum. Calyx straight, the upper tooth much the larger.

Tribe V. SCUTELLARINEae. Stamens 4, ascending and parallel. Calyx bil.a.b.i.ate, closed in fruit; the rounded lips entire. Corolla bil.a.b.i.ate, the upper lip arched.

25. Scutellaria. Calyx with a helmet-like projection on the upper side.

Tribe VI. STACHYDEae. Stamens 4, parallel and ascending under the galeate or concave upper lip, the lower (outer) pair longer (except in n. 31, 32). Calyx 5--10-nerved, not 2-lipped (except in n. 26).

[*] Calyx reticulate-veiny, deeply bil.a.b.i.ate, closed in fruit.

26. Brunella. Calyx nerved and veiny; upper lip flat, 3-toothed, the lower 2-cleft.

[*][*] Calyx thin, inflated in fruit, obscurely nerved, 3--5-lobed, open.

27. Physostegia. Calyx 5-toothed or 5-lobed. Anther cells parallel.

28. Synandra. Calyx almost equally 4-lobed! Anther cells widely divergent.

[*][*][*] Calyx of firmer texture, distinctly 5--10-nerved or striate, 5--10-toothed.

[+] Stamens included in the short corolla-tube, its upper lip merely concave.

29. Marrubium. Calyx tubular, 5--10-nerved, and with 5 or 10 awl-shaped teeth.

[+][+] Stamens ascending under the galeate upper lip of the corolla.

[++] Stamens not deflexed after anthesis; naturalized from the Old World.

30. Ballota. Calyx somewhat funnel-form, expanding above into a spreading 5-toothed border. Nutlets roundish at top. Upper lip of the corolla erect.

31. Phlomis. Calyx tubular, the 5 teeth abruptly awned. Upper lip of the corolla arched.

32. Leonurus. Calyx top-shaped, the rigid spiny-pointed teeth soon spreading. Nutlets truncate and acutely 3-angled at top. Leaves cleft or incised.

33. Lamium. Calyx-teeth not spiny-pointed. Nutlets sharply 3-angled, truncate.

34. Galeopsis. Calyx tubular-bell-shaped; the 5 teeth spiny-pointed.

Anthers transversely 2-valved, the smaller valve ciliate.

[++][++] Stamens often deflexed or contorted after anthesis.

35. Stachys. Calyx tubular-bell-shaped, equally 5-toothed or the 2 upper teeth united into one. Nutlets rounded at top.

1. TRICHOSTeMA, L. BLUE CURLS.

Calyx bell-shaped, oblique, deeply 5-cleft; the 3 upper teeth elongated and partly united, the 2 lower very short. Corolla 5-lobed; the lobes narrowly oblong, declined, nearly equal in length; the 3 lower more or less united. Stamens 4, with very long capillary filaments, exserted much beyond the corolla, curved; anther-cells divergent and at length confluent.--Low annuals, somewhat clammy glandular and balsamic, branched, with entire leaves, and mostly solitary 1-flowered pedicels terminating the branches, becoming lateral by the production of axillary branchlets, and the flower appearing to be reversed, namely, the short teeth of the calyx upward, etc. Corolla blue, varying to pink, rarely white, small; in summer and autumn. (Name composed of ????, _hair_ and st?a, _stamen_, from the capillary filaments.)