76 



SILVA OF NORTH AMERICA. 



CUPULIFER^. 



or less thickly covered with stellate hairs on the upper surface, and clothed on the lower with pale or 

 yellow pubescence, and vary from an inch to three inches in length and from one to three quarters of 

 an inch in width, with pale slender midribs, few conspicuous primary veins running to the points of the 

 teeth or arcuate and united within the more or less thickened and revolute margins, reticulate veinlets, 

 conspicuous both above and below, and stout pubescent or tomentose petioles rarely more than a 

 quarter of an inch, although sometimes, especially on vigorous shoots, nearly an inch in length. In 

 the north and at high elevations the leaves fall in the autumn, but in southern New Mexico and 

 Arizona they sometimes remain on the branches until the appearance of the new growth of the following 

 spring, or fall gradually and irregularly during the winter. The flowers appear with the first unfold- 

 ing of the leaves, the staminate borne in short tomentose aments from one to two inches in length. 



The involucral scales of the pistillate flower are 



the pistillate sessile or on tomentose peduncles. The hairy calyx of the staminate flowers is divided 

 into acute segments shorter than the stamens, which are composed of slender filaments and broad 



oblong emarginate light yeUow glabrous anthers, 

 coated with pale tomentum, and the stigmas are red. The acorns, which are sohtary or in pairs, are 

 sessile or raised on stout hoary peduncles varying from a quarter of an inch to nearly two inches in 

 length ) the nut is oval, rounded and rather obtuse or sometimes acute at the apex, and from three 

 quarters of an inch to an inch long, with sweet seeds ; the cup is cup-shaped, thick, light reddish 

 brown and pubescent on the inner surface, hoary-tomentose on the outer, and covered by ovate acute 

 scales usually thickened and tumid on the back toward the base of the cup, and above its middle 

 ending in thin bright red free cihate tips ; or sometimes all the scales are thin with free tips. 



The seeds, raw or baked, are eaten by Indians and Mexicans, and furnish hogs with excellent food. 



In Colorado Quercus undulata grows on dry rocky mountain ridges mixed with clumps of shrubby 

 forms of Querciis Gamhelii, from which it can be readily distinguished by the blue color of the leaves ; 

 it is found in similar situations on the mountains of western Texas, and in New Mexico and southern 

 Arizona, where it is comparatively rare ; in central Arizona, south of the Colorado plateau, it covers low 

 mountain ranges with vast thickets from six to eight feet taU, furnishing valuable and nutritious fodder 

 to cattle and sheep, which eagerly browse on the leaves and young branches. In southern Utah and 

 Nevada it is less common and is local in distribution.^ 



Quercus undulata was discovered on the head-waters of the Canadian River in 1820 by Dr. Edwin 

 James,'^ the naturahst of the expedition sent under the command of Major Long by the government of 

 the United States to explore the Rocky Mountains. 



1 On the type specimen (Plate ccclxxxv. f. 4) of this species the apex, rather deeply cordate at the base, an inch long and three 

 preserved iu the herbarium of Columbia College in New York quarters of an inch broad, is the type of Liebmann's Quercus ^mea ; 

 city, the leaves are oblong, narrowed and rounded at the base, and a form with leaves of the same size and shape, but with spines- 

 acute and rounded at the apex, coarsely sinuate-dentate, pubescent cent teeth, is his Quercus pungens (the varieties pungens and Wrightii 

 with scattered stellate hairs on the upper surface, covered with of Engelmann), a not unusual plant from western Texas to south- 

 pale tomentum on the lower surface, and from an inch and a ern Utah and Nevada. In southern Arizona this spinescent-leaved 

 half to two inches and a half in length ; this is the variety Jamesii form sometimes bears larger and more undulate leaves (Plate 

 of Engelmann, and plants of this form produce leaves which vary ccclxxxv. f. 5), and in central and southern Arizona small ovate 

 from entire to deeply pinnatifid and from oblong to linear-oblong, acute sometimes entire or slightly spinescent broad or narrow acute 

 those on vigorous'shoots being deeply lobed with rounded or acute and mostly cordate leaves covered on the lower surface with pale 

 oblique lobes and sometimes three to four inches in length, with or yellow pubescence and from half an inch to an inch in length, 

 petioles sometimes nearly an inch long. An unattached nut, pre- This last, which produces small acorns with shallow cups usually 

 served with the type specimen of Quercus undulata which appears covered by thin scales, is the common Oak of the mountains of 

 in the original figure and in Nuttall's copy of it, probably belonged central Arizona, 

 to some other plant, as was suggested by Torrey himself. 2 ggg \i ^Q. 



A form with nearly oval pubescent leaves rounded or pointed at 



