240 TREES OF NORTH AMERICA 



(hoary-tomentose in 27); abortive ovules basal; stamens 6-8; styles dilated; lobes of 

 the leaves not bristle-tipped. WHITE OAKS. 

 Leaves mostly persistent until the appearance of those of the following year, revolute 



in the bud (convolute in 28). 

 Leaves yellow-green. 



Fruit sessile or short-stalked. 



Leaves oblong-lanceolate, entire or repand-dentate; inner surface of the nut 



hoary tomentose. 27. Q. Emoryi (F, H). 



Leaves oblong or obovate, entire, sinuate-toothed or lobed. 28. Q. dumosa (G). 



Fruit long-stalked; leaves oblong, elliptic or obovate, pale, glabrous or in one form 



densely tomentose below. 29. Q. virginiana (C). 



Leaves blue-green. 



Fruit usually in many-fruited long-stalked clusters; leaves broad-obovate, coarsely 

 reticulate-venulose. 30. Q. reticulata (H). 



Fruit solitary or in pairs. 



Cup of the fruit saucer-shaped; leaves ovate to ovate-oblong, entire. 



31. Q. Toumeyi (H). 



Cup of the fruit cup-shaped or hemispherical, oblong-lanceolate to broad-obovate, 

 pubescent below. 32. Q. arizonica (H). 



Cup of the fruit usually cup-shaped or turbinate. 



Leaves ovate, oval or obovate, usually cordate at base; fruit rather long- 

 stalked. 33. Q. oblongifolia (E, H). 

 Leaves oblong to obovate, usually cuneate or rounded or cordate at base. 



34. Q. Engelmannii (G). 

 Leaves deciduous in their first season. 

 Leaves blue-green. 



Arboreous; leaves oblong, lobed, spinescent-dentate or entire, pubescent below; cup 

 of the fruit shallow cup-shaped. 35. Q. Douglasii (G). 



Arborescent or shrubby. 



Leaves oblong to oblong-obovate, undulate-lobed; cup of the fruit saucer-shaped 

 to cup-shaped. 36. Q. Vaseyana (C). 



Leaves oblong-obovate to elliptic or lanceolate, undulate, serrate-toothed or irregu- 

 larly lobed; cup of the fruit hemispheric to cup-shaped. 37. Q. Mohriana (C) . 

 Leaves oblong to oblong-ovate, slightly lobed or entire; cup of the fruit cup- 

 shaped or rarely saucer-shaped. 38. Q. Laceyi (C). 

 Leaves yellow-green. 



Leaves entire or slightly lobed. 



Leaves different on upper and lower branches, oblong to oblong-obovate, slightly 

 lobed or entire. 



Cup of the fruit cup-shaped. 39. Q. annulata (C). 



Cup of the fruit shallow saucer-shaped. 40. Q. Durandii (C). 



Leaves similar on upper and lower branches, entire or slightly sinuate-lobed 



toward the apex, oblong or oblong-obovate. 41. Q. Chapmanii (C). 



Leaves more or less deeply sinuate-lobed. 



Leaves white-tomentulose below (sometimes green and pubescent in 43) . 



Leaves obovate or oblong, lyrately pinnatifid or deeply sinuate-lobed; cup of 



the fruit fringed by the awned scales. 42. Q. macrocarpa (A, C, F). 



Leaves obovate-oblong, deeply 5-9-1 obed or pinnatifid; nut often inclosed in 



the cup. 43. Q. lyrata (A, C). 



Leaves pubescent below. 



Leaves usually covered above with fascicled hairs, obovate, 3-5-lobed, their 

 lobes truncate or rounded. 44. Q. stellata (A, C). 



Leaves glabrous above at maturity. 



Leaves obovate to oblong; cup of the fruit shallow cup-shaped or slightly 

 turbinate, its scales usually thin. 45. Q. Garryana (B, G.) 



