GYMNOSPERMS 17 



timber-spruce of the northeastern United States, and furnishes much 

 rather tough lumber for use in floor-joists, scantling, and similar 

 pm'poses. 



3. P. alba, Link. White Spruce, Skunk Spruce, Cat Spruce. 

 A tall, rather conical tree, 60-70 ft. high. Leaves pale and with a 

 bloom sometimes | in. long. Cones cylindrical, with rounded ends, 

 about 2 in. long, falling inside of one year, A handsome tree, 

 valuable for timber, ranging far northward. 



4. P. excelsa, Link. Norway Spruce. A large tree. Leaves 

 dark green, |-1 in. long. Cones 5-7 in. long. Cultivated from 

 Em'ope. 



III. TSUGA, Carriere. 



Sterile flowers, clusters of stamens springing from the axils 

 of leaves of the preceding year. Cones terminal, on twigs of 

 the preceding year, drooping, thin-scaled, ripening the first 

 year. Leaves minutely petioled, short, flat, white beneath, 

 2-ranked. 



1. T. canadensis, Carriere. Hemlock. A large tree, in age 

 branchless below when growing in dense woods. When young the 

 spray is very graceful and abundant. Leaves short-linear. Cones 

 I in. or less in length. The wood is coarse and splintery, but useful 

 for fences and other rough work. The thick reddish bark is of 

 great value for tanning. 



IV. ABIES, Link. 



Sterile flowers from axils of leaves of the preceding year. 

 Cones erect, on the sides of the branches, with deciduous 

 scales, ripening the first year. Leaves scattered, but on hori- 

 zontal branches appearing 2-ranked, flat above, silvery, and 

 with a prominent midrib below. 



1. A. balsamea, Miller. Balsam Fir. A slender tree, 50-60 

 ft., occasionally 80 ft., high, with dense foliage. Leaves narrowly 

 linear, less than 1 in. long. Cones violet-colored until old, cylindri- 

 cal, 2-4 in. long. The bark contains many large blisters, filled with 

 the well-known Canada balsam. The wood is brittle, and of little 

 value. 



V. LARIX, Toum. 



Flower-spikes short, opening in early spring, before the 

 leaves ; the fertile ones, while still young, of a beautiful crim- 



