1881.] by the young naked Branches. 33 
leaf scar slightly exceeds the vertical diameter. Fig. 1,abc, 
illustrates the buds and bud scars of P. tremuloides. The buds 
are not viscid. The one lettered a isa Sane of a sihlages of a 
a 
FIG. 3. 
EXPLANATION OF THE FIGURES. 
‘des. a, scar and bud near base of branch, 
diam ; 4, natural size near the middle of a rapid ob Bator $s 
view re same enlarged three diameters 
Fic. 1 ee tremulot 
Fic. 2.— Populus grandident ata. a, dilerged front and side view of bud and scar 
near the base of a year’s ahs , the same farther up the stem; ¢, enlarged 
view near the ecivin of stem, 
size figure near the middle of a large poveee/ 
Fic. 3.— Popul: ral 6 
growth ; be, views igs middle ‘of slender growth; @, view near the base o 
enlarged three 
front and side 
