1360 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM 



Leaves not tomentose beneath. 



Leaves elongate-linear, 3 to 9 cm. long and 0.6 to 3.5 mm. wide, 



often glabrous 8. B. tenuifolia. 



Leaves not elongate-linear, if very narrow the blades usually less 

 than 3 cm. long, usuall}' lanceolate to ovate. -9. B. ternifolia. 

 Leaves opposite. 



Corolla lobes usually 3 to 5 mm. long, of an ovate or triangular-oblong type, 

 mostly erect or ascending; corolla yellow, red, white, or greenish white, 

 the tube 1 to 3.3 cm. long. 

 Inflorescences usually 3 or 5-fiowered, simply cymose, sometimes 1-fiowered; 

 leaves pinnately nerved. 

 Corolla red or yellow. 



Corolla lobes villous outside with coarse hairs; leaves mostly rounded- 

 ovate and cordate or subcordate at base 10. B. subcordata. 



Corolla lobes glabrous outside; leaves not cordate at base. 

 Corolla tube glabrous within; leaves 2 to 3.5 mm. wide. 



11. B. macilenta. 



Corolla tube more or less villous within; leaves 5 mm. wide or wider. 



Caly.x tube densely puberulent or short-hirtellous, the lobes 2 to 4.5 



mm. long; inflorescences mostly 3-flowered._12. B. versicolor. 



Calyx tube glabrous or very sparsely villous or puberulent, the 



lobes 4 to 11 mm. long; inflorescences mostly with 5 or more 



flowers. 



Corolla 1.3 to 1.5 cm. long 13. B. conzattii. 



Corolla 2.5 to 4 cm. long. 



Pedicels 3 mm. long or shorter; leaves pale beneath, the lateral 



nerves mostly obsolete 14. B. chrysantha. 



Pedicels 6 to 28 mm. long; leaves subconcolorous, the lateral 



nerves evident 15. B. laevis. 



Corolla white or greenish white. 



Corolla densely villous outside 16. B. villosa. 



Corolla glabrous outside. 



Corolla tube 2.4 to 3.3 cm. long 17. B. tnacrantha. 



Corolla tube 1 to 2 cm. long. 



Leaves, at least part of them, suborbicular, abruptly long or short- 

 acuminate; pedicels 2 to 8 mm. long; corolla tube 1.8 to 2 cm. 



long 18. B. heterophylla. 



Leaves mostly ovate or lanceolate, not abruptly acuminate; 

 pedicels 3 mm. long or shorter; corolla tube 1 to 1.5 cm. 



long 19. B. multiflora. 



Inflorescences manj- -flowered, compound; corolla tube usually 6 to 11 mm. 

 long; leaves sometimes palmately nerved. 

 Leaves 3 or 5-nerved from the base. 



Corolla hirtellous 20. B, quinquenervata. 



Corolla glabrous. 



Calyx hirtellous 21. B. oaxacana. 



Calyx glabrous 22. B. rekoi. 



Leaves pinnately nerved; corolla (so far as known) glabrous. 



Leaves puberulent beneath along the veins; calyx lobes 1 to 1.5 mm. 



long 23. B. gracilipes. 



Leaves glabrous; calyx lobe s 2.5 to 3.5 mm. long__24. B. dictyoneura. 

 Corolla lobes mostly 7 to 25 mm. long, of an oblong or elliptic type, spreading, 

 narrowed at base; corolla white, the tube often 4 cm. long or longer. 

 Leaves sessile, broadly ovate; calyx tube prolonged beyond the ovary. 



25. B. rosei. 



