and Old World Birches. 193 3 
EXPLANATION OF PLATES.* 
Puate V, figs. 1-6, BeTULA ALBA. 
Figure 1.—Leaf of young powerien branch of B ao Ebrh., from 
the Vosges Mts. eye: bervilles, France (Joa 
Ficure 2. ca of fru ruiting ate h of B. papyrifera, Moreh: from Lake 
innipeg, Manitoba ipods eau). 
Figure 3.—Leaf of fruiting branch of B. Nee i Hook., from Pend 
d’Oreille River, British cowebe (Lyall 
Figure 4.—Leaf of young branch o eee Ehrh., from Bohemia 
(Tause 
Figure 5.—Leaf of “fruiting branch of B. papyrifera, Marsh., from South- 
port, Maine (/ernald). 
Fiaure 6.—Leat of fr ruiting branch from Austria—after Ettingshausen and 
Pokorny, Phys. Pl. Aust. iii, t. 201, 
Puate V, figs. 7 to 12, B. ALBA, var. MINOR. 
Figure 7. rer of fruiting branch of B. tortuosa, Ledeb., from the Altai 
, Siberia (ex. herb, St. Pet jae 
Figure 8, — Lead of fruiting branch of B. odorata, var. tortuosa, Lange, 
m the Dovre Mis. Viawab-tal Lange, Fl, Dan. xvii, t. 
FIGUREs 9, 10. na es of original fruiting branches of B. papyracea, var. 
minor, Tuck., from Mt. Washin: ely New Hampshire 
Ficure 11. oo of dwarf for orm of B. papyracea, yer st ie Tuck., from 
t. Washington, New Hampabire (Fawo 
Figure 12. —Leaf of fruiting branch of B, odorata, —s minor, Rosenvinge 
in herb., from Greenland yaa hy 
Prater V, figs. 13, 14, B. ALBA var. CARPATICA. 
FIGURE 13.—Leaf of Anise branch of B. borealis, Spach, from Anticosti, 
uebec ag 
Ficure 14, Tee fof: 8. : aloe subsp. pubescens, ¢ carpatica, Regel, from 
Laoland| (Regel). 
Puate V, figs. 15 to 18, Piate VI, figs. 19 to 22, B. PENDULA. 
Figures 15, Bak ert ves of you owering branch of B. alba, subsp. ver- 
é edie Sta "Hegel (type of B. alaskana, Sargent) from 
Sas catelirone (Bourgeau). 
Ficuress 16, si .—Leaves of fruiting branch of B. verrucosa, Ehrh., from 
i ytt). 
Figure 19,—Leaf of fruiting Peaneh of B. pendula, from Warren, Ilinois 
. M. Umbach, sheet No. 351,017 U. S. Nat. Herb.). 
Ficure 20.—Leaf of fru ae branch from, Gotland, Sweden (Blomberg). 
Figure 21. BR ro of B. alba, subsp. ma urica, Rege , from Mandschuria— 
r the o odio dhabtcakiont (Rogel, Bull. Soe. Pag Nat. Mose 
1865, t. 7, fig. 15). 
FiGuRE 22.-—-Leaf of fruiting branch of B 6 resinifera, Regel, 
rom Nushagak River, Yukon District, it, Aleks (McKay). 
Pate VI, figs. 23, 24, B. PENDULA, var. JAPONICA. 
Figure 23, BP cova of B. alba, subsp. latifolia, a Tauschii, eo en 
sia—after Regel, Bull. Soc. Imp. Nat. Mose., 1865, t. 7, fig. 11. 
Figure 24, ber f of B. kenaica, W. H. Evans, from Cook Inlet, Alaska 
(Coville and t Knahey, No. 2412). 
e plates illustrating this paper have been carefully prepared by Mr. 
F, ‘deeece Mathews. Unless otherwise stated, the figures are life-sized. 
