350 Class XXI. Order VIII. 



and, when young, pubescent. The acorns are pretty large, 

 ovate, contained in the enlarged calyx, which forms a cup of a 

 hemispherical form, scaly and uneven on the outside. 



The wood of the white oak is superior to any species in the 

 northern states for strength and durability. Its timber is much 

 used in ship building, in frames, in mills, in waggons, ploughs, 

 &c. and for the staves and hoops of casks. The great consump- 

 tion of it for these purposes, has rendered it comparatively 

 scarce, so that poorer species are often substituted in the work 

 shops of mechanics. 



QUERCUS BICOLOR. Willd. Swamp White Oak. 



Leaves oblong-ovate, downy, white underneath, 

 largely toothed, entire at base, the teeth unequal and 

 dilated ; fruit on long peduncles. Mich.f. sub. syn. 



Syn. QUERCUS PRINUS TOMENTOSA. Mich. 

 QUERCUS PRINUS DISCOLOR. Mich. f. 



This species grows exclusively in swamps and low grounds. 

 It is often brought to market as fuel, and is easily distinguished 

 by its bark, which separates into large, flat scales or plates. The 

 leaves are inversely ovate or wedge shaped, not sinuated, but 

 bordered with a serpentine line, producing large, obtuse teeth. 

 They are smooth above, but white and downy underneath. The 

 acorns grow in pairs or single, on long stalks. They are large, 

 oval, with a rather small, hemispherical cup. 



The wood of the swamp oak is strong, heavy, and flexible, 

 easy to split, and in point of durability approaches the white 

 oak. 



QUERCUS TINCTORIA. Bartram. Black Oak. 



Leaves slightly lobed, the lobes angular ; cup some- 

 what saucer shaped, acorn depressed-globular. Mich, 



sub. v. angulosa. 



The black oak grows to a large size, and is uniformly charac- 

 terized by the rough, and very dark coloured outer bark of its 

 trunk. The leaves have their sides divided into a number of 

 large, broad, but rather short lobes, furnished with a few mucro- 

 nated teeth and angles. Their base is obtuse, and their under 

 surface, while yeung, is slightly pubescent, or glandular. The 



