4p SALICACILE 157 



when the leaves are about one third grown, ovate, acute, dark red-brown, rather 

 thick- walled, 2 or 3-valved, about \' long; seeds obovate, minute, dark red-brown. 



A tree, 80-90 high, with a tall trunk 2-3 in diameter, short rather slender 

 branches forming a comparatively narrow round-topped head, and stout branchlets, 



marked by small elongated pale lenticels, coated at first with hoary caducous tomen- 

 tum, becoming dark brown and rather lustrous or ashy gray, or rarely pale orange 

 color and glabrous or slightly puberulous, or covered with a glaucous bloom in 

 their first winter, growing darker in their second year and much roughened by the 

 large thickened leaf-scars; usually much smaller and at the north rarely more than 

 40 tall. "Winter-buds slightly resinous, broadly ovate, acute, with bright red- 

 brown scales, about ^' long and about one half the size of the flower-buds. Bark on 

 young trunks divided by shallow fissures into broad flat ridges separating on the 

 surface into thick plate-like scales, becoming on old trunks f '-!' thick, light brown 

 tinged with red, and broken into long narrow plates attached only at the middle and 

 sometimes persistent for many years. Wood dull brown, with thin lighter brown 

 sapwood of 12-15 layers of annual growth; now often manufactured into lumber in 

 the valley of the Mississippi River and in the Gulf states, and as black poplar used 

 in the interior finish of buildings. 



Distribution. Southington, Connecticut, and Northport, Long Island, southward 

 near the coast to southern Georgia, through the Gulf states to western Louisiana, 

 and through Arkansas to southeastern Missouri, western Kentucky and Tennessee, 

 and southern Illinois and Indiana; in the north Atlantic states in low wet swamps, 

 and rare and local; more common south and west on the borders of river swamps; 

 very abundant and of its largest size in the valley of the lower Ohio and in south- 

 eastern Missouri, eastern Arkansas, and western Mississippi. 



4. Populus balsamifera, L. Balsam. Tacamahac. 



Leaves ovate-lanceolate, gradually narrowed and acute or acuminate at the apex, 

 rounded or cordate at the broad or rarely narrowed base, finely crenately serrate, 

 with slightly thickened revolute margins, coated when they unfold with the gummy 

 secretions of the bud and sometimes slightly puberulous, becoming thin and firm in 

 texture, deep dark green and lustrous above, pale green and more or less rusty and 

 conspicuously reticulate-venulose below, 3'-o' long, l'-3' wide, with thin veins run- 



