S36 sbo^ulIcbae (biech family) 



papyracea, var. Tuckerm.) — Alpine regions and cold bogs, Lab. to Sask., s. to 



n. N. E. and Minn. (Greenl.) 



^- -1- Wings narrower than or rarely as broad as the body of the fruit, or want- 

 ing ; shrubs with dark scarcely papery bark, subsessile or short-petioled 

 thickish or coriaceous small leaves, and narrowly ovoid or cyliadric mostly 

 erect sessile or short-peduncled catkins. 



++ Young branchlets pubescent with long soft hairs. 



7. B. pumila L. (Low or Swamp B.) Stems 0.5-3 m. high, erect or ascending, 

 not glandular; younj branches and lower fac^ of young leaves mostly soft- 

 downy; leaves obovate, orbicular, or renlform, 1-3.5 cm. long, not resiniferous, 

 pale beneath, veinletson both faces finely reticulated ; fruiting catkins 0.7-3 Cm. 

 long, 5-9 mm. thick. — Bogs, Lab. and Nfd. to Ont., s. to n. N. J., O., Ind., HI., 

 and Minn. (Eurasia.) 



Var. glandulifera Regel. Toung branchlets and leaves resiniferous or glandu- 

 lar-dotted. — (Mt. and Mich, to Minn, and Sask. 



■H- i-f Young branchlets glabrous or at most minutely puberulent, conspicuously 

 dotted with resinous wart-like glands. 



8. B. glandulbsa Miohx. (Dwarf B.) Stems erect or depressed, 0.3-2 m. 

 high, or when alpine procumbent ; leaves icedge-obovate, 0.5-3 cm. long, green 

 and glabrous both sides, slightly reticulated ; fruiting catkins 0.5-2.6 cm. long, 

 .3-7 mm. thick. — Arctic barrens, s. to mts. of N. B., Me., and N. H. ; L. 

 Superior, Minn., etc. (Asia.) Var. rotundif6lia (Spaoh) Regel. Very 

 dwarf ; leaves orbicular or reniforni. — Arctic regions to mts. of Me. and N. H. 

 (Alaska ; Asia.) 



5. XlNUS [Tourn.] Hill. Alder 



Sterile catkins with 4 or 6 bractlets and 3 (rarely 6) flowers upon each short- 

 stalked shield-shaped scale ; each flower usually with a 3-5-parted calyx and 

 as many stamens ; filaments short and simple ; anthers 2-oelled. Fertile catkins 

 ovoid or ellipsoid ; the fleshy scales each subtending 2 flowers and a group of 

 4 little scalelets adherent to the scales or bracts of the catkin, which are woody 

 in fruit, wedge-obovate, truncate, or 3-5-lobed. — Shrubs or small trees with 

 few-scaled leaf-buds and solitary or often racemose-clustered catkins. (The 

 ancient Latin name. ) 



* Flowers developed with the leaves; the sterile catkins from naked buds formed 



the preceding season; the fertile from scale-covered buds; fruit with a 

 conspicuous thin wing. 



1. A. crispa (Ait.) Pursh. (Green or Mountain A.) Shrub with young 

 branches and peduncles sparingly puberulent or glabrate ; leaves round-oval, 

 ovate or slightly heart-shaped, in maturity 3-6 cm. long, glutinous and smooth, 

 or slightly pubescent on the principal veins beneath, irregularly serrulate or 

 biserrulate with very fine and sharp closely set teeth, the margins often puck- 

 ered ; fertile catkins slender-stalked, loosely racemose, in maturity 1-1.5 cm. 

 iong. (A. viridis Man. ed. 6, in part, not DC. ; A. Alnobetula Am. auth., in 

 part, not K. Koch.) — Cool shores and mts.. Lab. to N. B. ; Mt. Katahdin, Me. ; 

 Mt. Washington, N. H. ; Whitefaoe Mt., N. Y. ; and on the mts. to N. C. 



2. A. m611is Fernald. (Downy Green A.) Shrub or small tree; young 

 branches and peduncles permanently soft-pubescent ; leaves permanently covered 

 beneath with dense soft hairs, in maturity 4.5-11 cm. long ; mature fertile catkins 

 1.2-2 cm. long. ^{A. viridis Man. ed. 6, in part, not DC. ; A. Alnobetula Am. 

 auth., in part, not K. Koch.) — Damp thickets and exposed rooky banks, s. Nfd. 

 to L. Winnipeg, s. to s. Me. and N. H., w. Mass., N. Y., and L. Superior. — 

 Ordinarily distinct, but possibly an extreme variation of A. crispa. 



* * Flowers developed in earliest spring before the leaves ; the catkins all from 



naked buds formed the preceding season ; fruit wingless or with a narrow 

 coriaceous margin. 



