726 TREES OF NORTH AMERICA 



the trunk '-!' thick, gray tinged with red, and divided by longitudinal furrows into 

 broad rounded ridges covered with small thick appressed scales. 'Wood heavy, hard, 

 very close-grained, brown tinged with red, with lighter colored sapwood of 80-90 

 layers of annual growth ; sometimes used locally for the handles of tools and the 

 bearings of machinery. The leaves have a pleasant acidulous taste, and are reputed 

 to be tonic, refrigerant, and diuretic, and are occasionally used in domestic practice in 

 the treatment of fevers. 



Distribution. Well-drained gravelly soil on ridges rising above the banks of 

 streams; southeastern Pennsylvania to southern Indiana and middle Tennessee, and 

 southward to the coast of Virginia and along the Alleghany Mountains to western 

 Florida, the shores of Mobile Bay, and through the elevated regions of the Gulf 

 states to western Louisiana; of its largest size on the western slopes of the Big 

 Smoky Mountains, Tennessee. 



Often cultivated as an ornamental plant in the eastern states and hardy as far north 

 as eastern New England, and occasionally in western and central Europe. 



5. XOLISMA, Raf. 



Trees or shrubs, with slender terete branchlets, and fibrous roots. Leaves petiolate, 

 membranaceous or coriaceous. Flowers on slender pedicels from the axils of ovate 

 acute bracts, in axillary and terminal umbellate fascicles or panicled racemes; calyx 

 persistent, 4-5-toothed or parted, the divisions valvate in the bud; corolla globular, 

 4-5-toothed or lobed, the lobes imbricated in the bud; stamens 8-10, included; 

 filaments flat, incurved, usually slightly adnate to the base of the corolla, dilated 

 and bearded at the base, geniculate; anther oblong, the cells opening below the 

 apex by large oblong pores; disk 10-1 obed; ovary 5-celled, depressed in the centre; 

 style columnar, stigmatic at the apex; ovules attached to a placenta borne near 

 the summit of the axis, anatropous. Fruit ovoid, many-seeded, loculicidally 5-valved, 

 the valves septiferous and separating from the placentiferous axis, 5-ribbed by the 

 thickening of the valves at the dorsal sutures, the ribs more or less separable in 

 dehiscence. Seeds minute, pendulous, narrow-oblong; seed-coat loose, thin, cellular- 

 reticulate, produced at the ends beyond the nucleus into short fringe-like wings; 

 embryo axile in fleshy albumen, cylindrical, elongated; cotyledons much shorter 

 than the terete radicle turned toward the hilum. 



Xolisma with about sixteen species is confined to North America, the West Indies, 

 and Mexico. Of the two species which occur in the United States one is a small tree. 



The generic name is of doubtful derivation. 



1 . Xolisma ferruginea, Hell. 

 {Andromeda ferruginea, Silva N. Am. v. 131.) 



Leaves cuneate-obovate, rhombic-obvate or cuneate-oblong, acute or rounded at 

 the apex, usually tipped with a cartilaginous mucro, gradually wedged-shaped at 

 the base, and entire, with thickened revolute margins, scurfy when they unfold, 

 and at maturity thick and firm, pale green, smooth and shining or sometimes obscurely 

 lepidote above, covered below with ferrugineous or pale scales, 1' 3' long, ^-'- 1^' wide, 

 with prominent midribs and primary veins and broad conspicuous reticulate veinlets, 

 Appearing in early spring and persistent until the summer or autumn of their second 

 year; their petioles short, thick, much enlarged at the base. Flowers y in diameter, 

 chiefly produced on branches of the year or occasionally on those of the previous 



