Procecdincrs of the Ohio State Academy of Science 135 



1. Betula populifolia Marsh. American White Birch. 

 A slender, short-lived tree with smooth white bark, tardily sep- 

 arating in thin sheets. Autumn leaves pure yellow. Wood soft, 

 white, not durable ; used for making spools, shoe-pegs, etc. 

 Leaves tremulous like those of the aspens. In moist or dry soil. 

 N. B. to Out., and Del. 



2. Betula papyrifera Marsh. Paper Birch. A large 

 tree with chalky white bark separating in thin layers. The bark 

 is very water-proof and is used for making canoes by Indians and 

 trappers. Wood rather heavy, hard, and very close-grained ; de- 

 cays rapidly when exposed ; used for making spools, pegs, shoe- 

 lasts, woodenshoes, wagon hubs, ox-yokes, wood-carving, wood 

 pulp, and in wood turnery. Xewf. to Alaska, Penn., J\Iich., Neb., 

 and Wash. 



3. Betula nigra L. River Birch. A slender tree with 

 reddish or greenish-brown bark peeling off in very thin layers. 

 Branches long and slender, arched and heavily drooping. Wood 

 rather light, hard, strong and close grained ; used for furniture 

 and turnery. "Birch brooms"" are madic from the twigs. Along 

 -Streams. Mass. and N. H. to Iowa, Kan.. Fia., Tex., and Ohio. 



4. Betula lenta L. Sweet Birch. A large tree with dark 

 brown, close, smooth bark, becoming fnrrr.wed and not separating 

 in layers. Wood hard, fine-grained, of a reddish tint; used for 

 cabinet-work. Newf. to Ont., Fla., Tenn., and Ohio. 



5. Betula lutea Mx. f. Yellow Birch. A large tree with 

 yellowish or gray bark, separating in thin layers or close. Au- 

 tumn leaves pure yellow. Wood hard and close-grained ; used in 

 making furniture, wheel-hubs, pill-boxes, etc. Newf. to Man., 

 N. Car., Ga., Tenn., and Ohio, 



*. Betula alba L. European White P)irch. A t;-ee with 

 ■chalky-white bark, mu.:h cidiivated for ornament, especially the 

 "weeping" and cut-leaved varieties. 



19. Alnus Gaert. Alder. 



Shrubs or trees with the flowers in aments, monoecious. 

 Pith 3-angled ; buds stalked. Nuts small, compressed, in woody 

 cone-like catkins, which are persistent throughout the year. 



