Nineteenth Annual Meeting. 107 



( Order Cupuliferse.) 

 33. QuEBOus. Oak. 

 Acorns on wood of the season; i. e., perfected the iirst year (a). 

 Acorns on wood of previous season; i. e., perfected the second year (/). 

 a. Lvs. lyrate or pinnatifid [b). 

 a. Lvs. coarsely toothed but not lobed {e). 



b. Lvs. wedge-shaped at base; fruiting peduncle much longer than petiole (59). 

 b. Lvs., etc., not as above (c). 

 c. Cup deep, scales pointed, upper ones awned, mostly mossy-bordered (58). 

 c. Cup hemispherical or saucer-shaped, not mossy-fringed (rf). 



d. Lvs. bright green above ; cup rough or tubercled, much shorter than 



acorn (5fi). 

 d. Lvs. pale and rough above; cup not tubercled, i or i length of acorn (57). 

 e. Fruiting peduncle longer than petiole, lvs. wedge-shaped at base (59). 

 e. Fruiting peduncle shorter than petiole, lvs. obtuse at base (60). 



/. Lvs. entire, lance-oblong, shining above, downy underneath (65). 



/. Lvs. widening above, 3 or 5-lobed, sometimes with one or two lateral, 



bristle-tipped teeth, rusty beneath, shining above, 4''-9'' long (63). 

 /. Lvs. pinnatifid or lobed, not coriaceous, teeth or lobes bristle-pointed (g). 

 g. Cup saucer-shaped, very much shorter than the acorn (h). 

 g. Cup hemispherical, with a conical base, half covering the acorn (62). 



h. Cup 9-12 lines broad; acorn 1^ or less long; lvs. rarely deeply pinnatifid (61). 

 h. Cup 5-7 lines broad; acorn 5-7 lines long; lvs. deeply pinnatifid, lobes di- 

 vergent (64). 



66. ij. alba, L.; White Oak. A large tree; wood strong, very heavy, hard, tough, 

 brown in color; mature lvs. smooth, pale or glaucous beneath, bright green 

 above, obovate-oblong, 3-9 obtuse lobes ; cup saucer-shaped, rough, much 

 shorter than the acorn, which is ovoid or oblong, and about 1^ long. 



57. Q. obfusiloba, Mx.; Post Oak, Iron Oak. Rarely exceeding 75 feet in height; 



wood heavy, hard; lvs. grayish or yellowish downy beneath, pale and rough 

 above, 5-7 rounded, divergent lobes; cup deep, saucer-shaped, smooth, ^ or + 

 the length of the acorn, which is ovoid, and 6-9 lines long. 



58. Q. macrocarpa, Mx.; Burr Oak. A large tree; wood heavy, hard, strong, tough; 



lvs. obovate or oblong, lyrate or deeply sinuate-lobed, or nearly parted; downy 

 or pale beneath; cup deep, thick, scales pointed, upper ones awned and 

 "mossy;" acorn half or entirely immersed in the cup, broadly ovoid, l''-l2''long. 



59. Q. bicolor, Willd.; Swamp White Oak. A large tree; wood heavy, hard, strong, 



tough; lvs. obovate or oblong-obovate, cuneate at base, coarsely sinuate-crenate, 

 soft, downy and hoary beneath, main primary veins 6-8 pairs; fruiting 

 peduncle much longer than the petiole; cup hemispherical, half the length of 

 acorn, which is scarcely 1^ long; scales pointed, sometimes "mossy." 



60. Q. prinoides, Willd.; Yellow Oak, Chinquapin Oak. A large tree, or reduced to a 



shrub; wood heavy, hard, very strong; lvs. oblong or lanceolate, undulately 

 sharp, crenate-toothed, minutely downy beneath; the main primary veins 

 10-16 pairs; fruiting peduncles shorter than the petioles; cup hemispherical, 

 thin; acorn 7-9 lines long. 



61. Q. rubra, L.; Red Oak, Black Oak. A large tree; wood heavy, hard, strong; Iva. 



glabrous, or nearly so, rather thin, oval or obovate-oblong, (rarely deeply) 

 pinnatifid, lobes rather acute; cup saucer-shaped or flat, with a narrow raised 

 border, 9-12 lines in diameter, very much shorter than the oblong-ovoid, 

 1^-long acorn. 



