FAGACE^ 227 



dulous clustered aments, from separate or leafy buds iu the axils of leaves of the 

 previous year, or from the axils of the inner scales of the terminal bud or from 

 those of the leaves of the year; calyx campanulate, lobed or divided to the base into 

 4-7, usually G, membranaceous lobes; stamens 4-6, rarely 2, or 10-12, inserted on 

 the slightly thickened torus, with free filiform exserted filaments and ovate-oblong 

 or subglobose glabrous or rarely hairy 2-celled usually yellow anthers; pistillate soli- 

 tary, subtended by a caducous bract and 2 bractlets, in short or elongated few- 

 flowered spikes from the axils of leaves of the year; calyx urn-shaped, with a short 

 campanulate 6-lobed limb, the tube adnate to the incompletely 3 or rarely 4 or 

 o-celled ovary inclosed more or less completely by an accrescent involucre of imbri- 

 cated scales, becoming the cup of the fruit; styles as many as the cells of the ovary, 

 short or elongated, erect or incurved, dilated above, stigmatic on the inner face or at 

 the apex only, generally persistent on the fruit; ovules anatropous or semianatropous, 

 2 in each cell. Fruit a nut {acorn) maturing in one or in two years, ovoid, globose, or 

 turbinate, short-pointed at the apex, 1-seeded by abortion, marked at the base by a 

 large conspicuous circular scar, with a thick shell, glabrous or coated on the inner 

 surface with pale tomentum, more or less surrounded or inclosed in the accrescent 

 cupular involucre of the flower (cup), its scales thin or thickened, loosely or closely 

 imbricated. Seed marked at the base or at the apex or rarely on the side by the 

 abortive ovules; cotyledons thick and fleshy, usually plano-convex and entire. 



Quercus inhabits the temperate regions of the northern hemisphere and high 

 altitudes within the tropics, ranging in the New World southward to the mountains 

 of Colombia and in the Old World to the Indian Archipelago. Two hundred and 

 seventy-five species have been described; fifty-two are North American; of these 

 five are shrubs. Of exotic species, the European Quercus pedunculata, Ehrh., and 

 Quercus sessilijiora, Salisb., have been frequently cultivated as ornamental trees iu 

 the eastern United States, where, however, they are usually short-lived and unsatis- 

 factory. Many of the species are important timber-trees; their bark is often rich in 

 tannin and is used in tanning leather, and all produce wood valuable for fuel and in 

 the manufacture of charcoal. 



Quercus is the classical name of the Oak-tree. 



CONSPECTUS OF THE NORTH AMERICAN ARBORESCENT SPECIES. 



1. Fruit maturing at the end of the second season {except 22) ; shell of the acorn silky- 

 tomentose on the inner surface ; leaves or their lobes bristle-tipped. Black Oaks. 

 *Stamens usually 4-6 ; styles elong-ated, finally recurved ; abortive ovules basal. 

 --Leaves deciduous in their first autumn or winter. 

 M-Leaves pinnately lobed, convolute iu the bud. 

 Leaves green on both sides. 



Cup saucer-shaped ; leaves g-labrous, with exception of axillary tufts of hairs ; 

 winter-buds glabrous or puberulous. 

 Cup broad and thick. 



Leaves dull green above, pale yellow-green below, oblong-obovate to 

 oblong, the lobes tapering gradually from broad bases and acute 

 and usually dentate at the apex. 1. Q. rubra (A). 



Cup thin and narrow ; leaves lustrous. 



Leaves obovate, sinuate-lobed by deep wide sinuses, the spreading lobes 

 acute or obtuse, usually coarsely repand-dentate. 



2. Q. palustris (A, C). 



Leaves oval or obovate, glabrous, sinuately lobed, their lobes usually 



acute and entire. 3. Q. Georgiana (C). 



