FAGACEAE. 31 



15. Buds and twigs rather dark. (9). Q. ellipsoidalis. 

 Buds and twigs bright brown: Texas. Q. texana. 



16. Buds subglobose or ellipsoid, nearly or quite glabrous. 17. 

 Buds ovoid or conical-ovoid. 22. 



Buds distinctly conical. 27. 



17. Evergreen: buds small. (Live oak). (10). Q. virginiana. 

 Deciduous. 18. 



18. Buds invested by long narrow stipules. (11). Q. Cerris. 

 Stipules lacking or inconspicuous. 19. 



19. Bark exfoliating from the branches. (12). Q. bicolor. 

 Bark not exfoliating. 20. 



20. Buds small (scarcely 3 mm.), pale. (13). Q. Durandii. 

 Buds medium-sized. 21. 



21. Twigs buff: buds pale brown. (Overcup oak). Q. lyrata. 

 Twigs gray or purple, often glaucous: buds deep brown. 



(White oak). (14). Q. alba. 



22. Twigs and buds gray-pubescent. (15). Q. macrocarpa. 

 Twigs yellow-scurfy: buds dull, silky. (16). Q. stellata. 

 Twigs glabrous: buds brown-puberulent or glabrous. 23. 



23. Buds rather glossy blood-red, glabrate. Q. Margaretta. 

 Buds very large, gray-pubescent. (17). Q. dentata. 

 Buds light brown or the scales pale-margined. 24. 



Buds deep "brown or red-brown. 25. 



24. Shrub. (Chinquapin oak). Q. prinoides. 

 Tree. (Yellow oak ). (18). Q. Muehlenbergii. 



25. Buds terete: twigs gray or purple. Q. alba. 

 Buds somewhat grooved, often brown-silky. 26. 



26. Twigs reddish. (English oak). (19). Q. Robur. 

 Twigs olive or brown. (Cow oak). Q. Prinus. 



27. Buds light brown. 28. 

 Buds deep brown. 29. 



28. Bud-scales brown- or rosy-margined. Q. grosseserrata. 

 Bud-scales not darker at margin. Q. crispula. 



29. Buds dull: outer scales pale-margined. Q. montana. 

 Buds glossy: scales not pale-margined. (20). Q. sessiliflora. 



