PINACEiE 311 



long, bluntly pointed, with 2 to 3 stomatic lines on 

 each side. — P. excelsa. 

 Shoots greyish yellow, glabrous or with minute hairs on 

 the pegs from which the leaves arise ; buds slightly 

 resinous, with entire rounded scales. — P. Alhertiana. 

 Shoots conspicuously hairy. 



Terminal bud with awl-shaped outer scales equalling or 



exceeding the bud in length. 



Shoots covered with short glandular hairs ; foUage 



bluish or glaucous green, about \ in. long. — P. 



nigra. 



Shoots as in P. nigra ; leaves yellowish or dark green, 



curved, |-| in. long. — P. rubra. 

 Shoots reddish with short non-glandular hairs, leaves 

 slender, \-\ in. long. — P. Glehni. 

 Terminal bud without awl-shaped scales or these do not 

 equal the bud in length. 

 Shoots greyish or pale brown, often densely bristly ; 

 leaves sub -compressed, often bevelled at apex, 

 ^f in. long, buds often resinous, stomatic lines 

 unequal. — P. likiangensis. 

 Leaves shorter and slenderer, more crowded, closely 

 pressed to shoot on upper side. — P. likiangensis, 

 var. purpurea. 

 Shoots greyish yellow with minute glandular hairs, 

 smelling disagreeably when bruised, leaves |— 1 in. 

 long. — P. Engelmanni. 

 Shoots reddish brown with minute non -glandular 

 hairs ; leaves t—k in. long, with 3-4 stomatic lines 

 on each side. — P. obovata. 



Picea alba, Link. 



White Spruce. 



Picea canadensis, Britton, Sterns and Poggenberg ; P. nigra, var. 

 glauca, Carriere ; Abies alba, Michaux ; A, canadensis, Miller ; Pinus 

 alba, Lambert ; P. canadensis, Dviroi (not Linnaeus). 



Canadian Spruce ; Cat Spruce ; Double Spruce ; Single Spruce ; Skunk 

 Spruce ; Spruce Pine. 



A tree 70-100 ft, high, and 9-12 ft. in girth at its best in 

 N. America, but usually 50-70 ft. high, and 3-4 ft. in girth, 

 becoming shrubby at its northern limit. Bark thin, |-^ in. thick, 

 greyish brown, scaly. Branches long, thick, bending downwards 

 at the trunk, the points upturned. Yoking shoots slender, without 

 down, or in the far north-western forms sometimes finely downy, ^ 

 often glaucous, becoming dark yellowish brown or pale brown 



1 Sudworth, The Spruce and Balsam Fir Trees of the Rocky Mountain Region, 

 p. 8, (1916). 



