LABIATE. 343 



10. LYCOPUS. Stamens only 2 with anthers; the upper pair sterile rudiments or else 

 wanting. Calyx canipanulate, 4-5-tootlie(l, naked in the throat. Upper lohe of corolla 

 entire. Nutlets 3-sided, truncate at top, narrow at base, thickened-marginc<l. 



* * * Corolla more or less evidently bilabiate ; the upper lip erect, entire or emarginate, 

 or in Monardel/a 2-cleft; the lower spreading and 3-cleft, destitute of bearded ring within, 

 except in PoUomintha. Calyx striate-nerved or costate, not much changed after 

 flowering. 



-K- Stamens distant and straight, often divergent, never convergent nor curved. 



++ Antheriferous stamens only 2 ; with or without abortive rudiments of the upper pair. 



ll.CUNILA. Calyx ovate-tubular, equally 5-toothed, very villous in the throat, 10-^ 

 nerved. Upper lip of corolla emarginate; the lower somewhat equally 3-cleft. Stamens 

 long-exserted. Nutlets smooth. 



•H- -H- Antheriferous stamens 4, didynamous : calyx 15-nervcd. 



12. HYSSOPUS. Calyx tubular, equally 5-toothed, naked in the throat. Tube of corolla 

 short : upper lip emarginate ; the lower 3-cleft, its middle lobe larger and 2-cleft. Stamens 

 exserted, divergent : anther-cells linear, divaricate. 



++ -H- -H- Antheriferous stamens 4, didynamous: calyx 10-13-(in Monanlrlla 15-)nerved, 



= Naked in the throat : flowers capitate-verticillastrate, or sometimes sparser. 



1 3. PYCNANTHEMUM. Calyx ovate-oblong or tubular ; the 5 teeth equal, or the 3 

 upper more or less united. Corolla short, with entire or barely emarginate upper lip, and 

 3-cleft lower one; the lobes all short, ovate, obtuse. Stamens little unequal: anther-cells 

 parallel. 



14. MONARDELLA. Calyx tubular, narrow ; the 5 teeth equal or nearly so. Corolla 

 glabrous within ; the 2-cleft upper lip and lobes of the 3-parted lower one all linear or 

 narrowly oblong, plane. Stamens strongly or moderately unequal, exserted: anther- 

 cells often divergent or divaricate. Flowers densely capitate-verticillastrate in the man- 

 ner of Monarda. 



= = Calyx villous or hirsute-bearded in the throat : corolla short. 



15. ORIGANUM. Calyx ovate-campanulate, in our (introduced) species equally 5-toothed. 

 Stamens exserted. Flowers spicate- or capitate-verticillastrate, imbricated with broad 

 colored bracts. 



16. THYMUS. Calyx ovate, declined in fruit, villous in the throat, distinctly bilabiate ; 

 upi)er li]) 3-toothed, spreading; lower 2-cleft, its divisions subulate and ciliate. Flowers 

 scattered or crowded, the bracts inconspicuous. 



•f— -i- Stamens ascending (at least the lower part) or arcuate, often more or less con- 

 verging and sometimes ascending parallel under the erect upper lip of the corolla: con- 

 nective of the anther commonly more or less thickened, sometimes separating the 

 oblique or divaricate cells. 



++ Calyx only about 10-nerved. naked in the throat, not declined nor gibbous: fertile 

 stamens 4. 



17. SATUREIA. Calyx campanulate or short. Tube of the corolla short, or not ex- 

 ceeding the bracts. 



++ +-I- Calyx r2-15-nerved : upper lip of the corolla plane or slightly concave and straight, 

 as in the tribe generally. 



== Style beardless : anthers muticous. 

 a. Stamens 4, all antheriferous. 



18. MICROMERIA. Calyx oblong or tubular, terete, not gil)bous nor declined, about 

 equally o-tootlu'd. Corolla short, its straight tube usually shorter or hardly longer than 

 the calyx. Stamens arcuate, shorter than the corolla. 



19. CALAMINTHA. Calyx oblong or tubular, often gibbous, bilabiate ; the upper lip 

 3-tootlied or 3-cleft, the lower 2-f)arted. C'orolla witii a straight tube mostly exceeding 

 the calyx, and a conmionly enlarging throat. Stamens ascending ])arallel imder or 

 beyond the upper lip, or coimivitig in pairs. 



20. MELISSA. Calyx oblong-campanulate, bilabiate as in the preceding, but the broad 

 u|)per lip becoming flatter. Corolla rather short ; its tube at base declined, then ascend- 

 ing, inchided in the calyx. Otherwise like (Jalamiiithn. Leaves ovate, serrate, veiny. 



21. CONRADINA. C^lyx, &c., of C'dhunii.thi. Corolla with a narrow and straight tube 

 ratiier shorter than the calyx, abruptly bent backwards at the tliroat, deeply bilabiate, 

 ringont ; the upper lip somewhat concave and incurved, emarginate or retuse ; the lower 

 dependent, contracted at the base, deeply 3-h)bed ; the lateral lobes roundish, the dilated 



