430 FAGACEiE. 



THE CHESTNUTS. Genus CASTANEA Adams. 



Trees and shrubs of the northern hemisphere, with astringent watery juice, edible nuts 

 and very porous wood and of great economic value. Four or five species are known and of 

 these two are trees of eastern United States and one a shrub of the southern states. 



Leaves convolute in the bud, ovate to oblong-lanceolate, coarsely serrate and with straight 

 veins terminating in the teeth. Floivers appearing after the leaves, monoecious; the staminate 

 in interrupted erect axillary araeuts, several flowers together in the axils of small caducous 

 bracts : calyx campanulate. pale yellow, puberulous, with (J lobes imbricated in the bud ; 

 stamens 10-20, with long exserted filiform filaments and small yellow anthers, pistillate flowers 

 mostly at the bases of the upper staminate (androgynous) aments, sessile, and usually 2 or 3 

 together, surrounded with an involucre of many acute green bracts : calyx urn-shaped and 

 with G minute sterile stamens ; ovary 6-celled, with G spreading white linear styles and 2 

 ovules in each. Fruit maturing in autumn, nuts 1-3 together, with a globose mostly 4-valved 

 woody burr-like involucre, very prickly with stiff branching spines outside and velvety pubescent 

 inside ; nut flattened by mutual compression, short, ovoid, pointed and tipped with the remnants 

 of the style, with chestnut-brown coriaceous shell, lustrous below, pubescent above and with 

 large pale scar at base : seed solitary by abortion and marked by the abortive ovules at apex, 

 large, starchy and of delicious flavor. 



Castanea is the classical name of the Chestnut-tree. 



KEY TO THE SPECIES. 



Nuts 2-3 in an involucre, compressed; leaves green and glabrous both sides. ... C. dentata. 



Nuts solitary, not compressed ; leaves pale tomentose beneath C. pumila. 



For species see pp. 13'f-137. 



THE OAKS. Genus QUERCUS L. 



Trees and shrubs of nearly 300 species of the north temperate regions and high altitudes 

 of the tropics. From its representatives come some of our best hard woods, barks extensively 

 used for tanning purposes and the corks of commerce. The acorns of many species are an 

 important article of food for hogs, etc., and in some countries also for man. Oak-galls of 

 commerce develop on the branches of certain species and many dyes and other products may 

 also be recorded among the products of the genus. About fifty Oaks are natives of the United 

 States and more than half of these are found in the Atlantic states. 



Leaves deciduous or persistent, arranged in five ranks, pinnately veined and often pinnately 

 lobed, sometimes entire and sometimes variable on the same branch ; stipules scarious and 

 caducous or occasionally persistent. Floicers appearing with or before the leaves; the 

 staminate in clustered slender drooping catkins, from axils of the leaves or bud-scales of the 

 previous year or leaves of the present year, a single flower in the axil of each caducous scale of 

 the anient : calyx yellowish green, campanulate. deeply G-lobed ; stamens 4-12, with filiform 

 exserted filaments and yellow anthers; pistillate flowers solitary or in few-flowered spikes 

 from the axils of the leaves of the year, each flower svfljtended by a caducous bract and two 

 bractlets ; calyx urn-shaped, with tube adnate to the ovary, and limb of 6 short lobes ; ovary 

 mostly 3-celle'd with 2 ovules in each cell and 3 short or elongated styles, each flower nearly 

 enveloped by a scaly imbricated accrescent involucre. Fruit and ovoid-oblong or subglobose 

 1-celled nut (acorn) maturing in 1 or 2 years, with coriaceous shell having large circular scar 

 at base, each nut subtended or more or less enveloped in a woody cup of imbricated and more 

 or less united scales ; seed solitary and bearing abortive ovules at base or apex ; cotyledons 

 usually plano-convex and entire. 



Quer-cits is the ancient Latin name of the Oak-tree. 



KEY TO THE SPECIES. 



a Acorns maturing in autumn of the second year ; shells hairy inside ; abortive ovules at 

 apex ; stamens 4-G ; styles elongated ; leaves or their lobes bristle-tipped, deciduous 

 (Black Oaks) 

 b Leaves pinnately lobed, convolute in the bud and 

 c Green both sides ; cup of acorn 



d Saucer-shaped, shallow and wide ; cups 



e %-l in. wide, rather thick and not more than 14 investing the acorns ; leaves 



Dull green above and lobes widest at base Q. rubra. 



Lustrous green, lobes wide at apex Q. Texana. 



e' %-% in- wide, thin; leaves lustrous with lobes spreading and wide towards apex; 



acorn short-globose Q. palustris. 



d' Turbinate with 



e Small closely appressed scales 



f Acorn elliptical; cup Vi-V?, in. wide, leivp-; lustrous Q. ellipsoidalis. 



f' Acorn ovoid; cups mostly more than ij ui. wide; leaves dull green and 



