108 KAIiSAS ACADEMY OF SCIENCE. 



62. Q. tinetoria, Bartram; Black, Yellow, or Quercitron Oak. A large tree; wood heavy, 



hard, strong, not tough, coarse-grained. Lvs. glabrous or nearly so (pubescent 

 beneath when young), oval or obovate-oblong, lobes oblong, obtuse, mucro- 

 nate. Cup thick, 9 lines in diameter, covering half the acorn, which is 

 broadly or globular-ovoid. 



63. Q. nigra, L.; Black Jack, Jack Oak. A snaall tree; wood heavy, hard, strong. 



Lvs. broadly wedge-shaped (sometimes rounded at base), widely dilated and 

 3 (rarely 5) lobed at summit; rusty pubescent beneath, shining above; cup 

 top-shaped; acorn short ovoid. 



64. Q. palustris, Du Roi.; Pin Oak, Water Oak. A large or middle-sized tree; wood 



heavy, hard, very strong, coarse-grained. Lvs. glabrous or nearly so, oval or 

 oblong-obovate, deeply pinnatifid with divergent lobes and broad, rounded 

 sinuses; cup flat, saucer-shaped, very much shortar than the acorn, which is 

 ovoid-globose, 5-7 lines long. 



6.5. Q. imlrricaria, Mx.; Shingle Oak, Laurel Oak. A large tree; wood heavy, hard, 

 rather coarse-grained. Lvs. lanceolate-oblong, thickish, shining above, downy 

 beneath; cup between saucer-shaped and top-shaped. 



34. OsTBYA. Ieon-wood. 



66. O.Virginiana, Mich.; Hop Horn-beam, Iron-wood. A small tree; bark brownish, 



furrowed with fine longitudinal divisions; wood heavy, very strong and hard, 

 tough; lvs. serrate, 11-15 prominent veins; fr. hop-like in appearance. 



35. Cabpinus. Watee Beech. 



67. C.Caroliniana, 'Walter; Horn-beam, Blue Beech, Water Beech. A small tree: bark 



smooth, close, gray; wood heavy, very strong and hard; lvs. straight-veined, 

 resembling the beech; fr. catkin-like, loose, the bractlets open and foliaceous. 



(Order Betulaceie.) 



36. Betula. Bieoh. 



68. B. nigra, Ait.; Red Birch. A large tree, with greenish-brown bark, somewhat 



laminate, becoming torn into shreds; wood light, rather hard, strong, close- 

 grained; branchlets often clothing the trunk to the base; lvs. rhombic-ovate, 

 acute at each end, dark green above, pubescent. 



^Order Salicacete.) 



37. Salix. Willow. 



69. S. nigra, Marsh.; Black Willow. A shrub or small tree, sometimes 60 ft. high; lvs. 



narrowly lanceolate; smooth, except on petioles and midrib; green both sides; 

 branches brittle, pale yellow; trunk with blackish bark. Catkins on lateral 

 leafy branches of the season; stamens 3-6; pods mostly short, ovate. 



70. S. longifolia, Muhl.; Longleaved Willow. Shrubby or 15°-20° liigh; lvs. linear or 



lanceolate, elongated, long acuminate, remotely toothed with projecting teeth, 

 catkins on short lateral leafy branches; stamens 2; pods oblong-conical, ob- 

 tuse. 



71. S. discolor, Muhl.; Glaucous Willow. Rarely more than 20° high; lvs. lanceolate, 



ovate-lanceolate or oblong, entire at the base and apex, irregularly toothed on 

 the sides, sn\ooth, whitish glaucous beneath, catkins appearing before the 

 leaves; stamens 2; ovary densely silky. 



72. S. cordata, Muhl. var. vestila, Anders.; Heart leaved Willow. A straggling shrub 



or small tree, recent twigs tomentose; lvs. linear-lanceolate or oblong-lanceo- 



