LABIATE. 161 



-t- -t- -t- >- Corolla evidently 2-lipped. Stamens with anthers 4. 



I. Hysso'pus. Calyx tubular, 15-nerved, equally 5-toothed. Corolla 



blue-purple, short ; upper Up erect, flat, obscurely notched, the 

 lower 3-cleft, with the middle lobe larger and 2-cleft. Stamens 

 exserted, diverging. Flowers in small clusters, crowded in a 

 spike. Branches simple, wand-like. 



8. Pycnan'themam. Calyx short-tubular, 10-13-nerved, equally 5- 



toothed. The whitish or purplish flowers in small dense heads, 

 forming terminal corymbs. Aromatic plants, with narrow rigid 

 leaves crowded and clustered in the axils. 



9. Sat lire' ia. Calyx bell-shaped, not hairy in the throat, equally 5- 



toothed. Aromatic plants, with narrow leaves and purplish 

 spiked flowers. 



* * * Stamens only 2, parallel ; the anthers only 1-celled. Corolla 

 2-lipped. 



10. Moiiar'da. Calyx tubular, nearly equally 5-toothed, hairy in the 



throat. Corolla elongated, strongly 2-lipped, the upper lip narrow. 

 Stamens with long protruding filaments, each bearing a linear 

 anther on its apex. Flowers large, in whorled heads surrounded 

 by bracts. 



* * * * Stamens 4, the upper or inner pair longer ! Anthers approximate 

 in pairs. Corolla 2-lipped. 



II. Nep'eta. Calyx obliquely 5-toothed. Anthers approaching each 



other in pairs under the inner lip of the corolla, the cells of each 

 anther divergent. 



12. Dracocepb'alum. Calyx straight, 5-toothed, the upper tooth 



much the largest. Whorls of bluish flowers with awn-toothed or 

 fringed leafy bracts, in a crowded head or spike. 



13. Lophau'thas. Calyx obliquely 5-toothed. Stamens exserted, the 



upper pair declined, the lower ascending, so that the pairs cross. 

 Anther-cells parallel. Tall herbs with small flowers in inter- 

 rupted terminal spikes. 



***** Stamens 4, the lower or outer pair longer ! Anthers approxi- 

 mate in pairs. Corolla 2-lipped. 



14. Calaniiu'tlia. Calyx tubular, 2-lipped, often bulging below. Co- 



rolla 2-lipped, the upper lip not arched, the throat inflated. Flowers 

 pale purple, in globular more or less dense clusters which are 

 crowded with linear or awl-shaped hairy bracts. 



15. Mells'&a. Calyx with the upper lip flattened and 3-toothed, the 



lower 2-cleft. Corolla nearly white, the tube recurved-ascending. 

 Stamens curved and conniving under the upper lip. Flower- 

 cluster loose, few-flowered, one-sided, with few bracts resembling 

 the leaves. 



