THE TELLOW BIECH. 313 



rate, oval, witli conspicuous veins, turning yellow in tlie 

 autumn. Not one of the birches ever shows a tint ap- 

 proaching to red or purple in its foliage. The Black 

 Birch delights in moist grounds, and commonly occupies 

 a stand on moimtain slopes and on the banks of rivers. 

 When growing singly on a plain, or in an open space, it 

 takes a hemispherical shape, with its terminal and lower 

 branches drooping to some extent hke those of the elm. 

 This tree is conspicuous on craggy precipices, among the 

 mountains, whgre it extends its roots into the crevices of 

 the rocks, and spreads its branches over chasms and hol- 

 lows. On these sites it displays a variety of picturesque 

 forms, corresponding with the rudeness and the wildness 

 of the scenery around it. Nature has furnished this tree 

 with a chaffy or winged seed, which is soon wafted and 

 sown by the winds upon mountain-sides and among inac- 

 cessible rocks, where the soil collected in thin fissures 

 supplies it with sustenance. 



THE YELLOW BIECH. 



The Yellow Birch, named excelsa by botanists, from its 

 superior height, is perhaps the most beautiful of the genus. 

 Its branches are extremely numerous, long and slender, 

 corresponding with the superior length of its trunk, and 

 they are prone, like those of the elm, to equality in 

 size, and to divergency from nearly a common centre. 

 Indeed, where this tree has grown as an isolated standard, 

 it commonly displays a very symmetrical head, differing 

 in form from a perfect elm only by less inclination to 

 droop. The leaves of this species have much of the same 

 quality which I have remarked as peculiar to the beech, 

 every leaf standing erect upon its stem. The flexible ap- 

 pearance of the tree is derived entirely from its slender 

 flowing branches. 



