240 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Corolla nearly regular; leaves ovate to lanceolate. 



Plants not odorous; fertile stamens 2 .23. LYCOPUS. 



Plants strongly odorous; fertile stamens 4 24. MENTHA. 



Flowers terminal, or terminal and axillary in the uppermost axils, often with con- 

 spicuous colored bracts. 

 Bracts broad, much exceeding the flowers, whitish, yellowish, or purplish, very 



conspicuous 16. MONARDA. 



Bracts very nan-ow or, if broad, the upper ones, at least, not longer than the 

 flowers. 

 Flowers in spikes. 

 Plants soft-downy. 



Flowers white, spotted with purple; corolla 2-lipped 8. NEPETA. 



Flowers bright blue; corolla seemingly 1-lipped 1. AJXJGA. 



Plants glabrous or hairy, but not downy. 

 Flowers greenish yellow. Spikes long and somewhat slender, but stiff and 



dense 7. AGASTACHE. 



Flowers white or purple. 



Corolla 2-lipped ; spikes thick 10. PRUNELLA. 



Corolla nearly regular; spikes slender 24. MENTHA. 



Flowers in heads, occasionally with whorls in the axils of the upper leaves. 

 Plants corymbosely branched, stiffly erect. Flower heads often clustered. 



21. KOELLIA. 

 Plants simple or with few branches, often more or less procumbent. 



Corolla pale bluish, spotted; fertile stamens 2 17. BLEPHILIA. 



Corolla lavender, pinkish, or white; fertile stamens 4. 



20. CLINOPODITIM. 

 Inflorescence composed of loosely 1-several-flowered terminal or axillary clusters, of 

 racemes, or of loose interrupted spikes. 

 Calyx with a prominent protuberance on the upper side, not toothed. Corolla blue 



and white 6. SCUTELLARIA. 



Calyx without a protuberance on the upper side, toothed. 



Flowers in loose l-few-flowered clusters, axillary or terminal, or both, not in 

 spikes or racemes. 

 Corolla regular or nearly so, 5-lobed or cleft. 

 Calyx equally 5-lobed; stamens scarcely longer than the corolla. 



3. ISANTHUS. 

 Calyx with 3 long and 2 short teeth; stamens greatly exceeding the corolla. 



4. TRICHOSTEMA. 

 Corolla very irregular, 2-lipped. 

 Flowers mostly terminal, in cymose clusters. Plants corymbosely branched. 



22. CUNILA, 

 Flowers mostly axillary, in few-flowered clusters or solitary. 

 Leaves coarsely crenate or serrate, large. 

 Leaves reniform or rounded heart-shaped; flowers usually bluish. 



9. GLECOMA. 



Leaves ovate; flowers white 19. MELISSA. 



Leaves sparingly crenate or dentate, small. 

 Leaves broadly ovate, mostly rounded at the base; stamens 4. 



20. CLmOPODIUM. 

 Leaves oblong-ovate, acuminate at the base; stamens 2. 



18. HEDEOMA. 



Flowers in spikes or racemes. 

 Inflorescence a loose raceme. Flowers yellow; leaves large. 



25. COLLmSONIA. 



