BETULACEZ. SILVA OF NORTH AMERICA. 55 
BETULA PAPYRIFERA, var. CORDIFOLIA. 
Canoe Birch. 
LEAVES ovate, cordate at the base. 
Betula papyrifera, var. cordifolia, Fernald, Rhodora, iii. 
173 (4901). 
Betula cordifolia, Regel, Nouv. Mém. Soc. Nat. Mose. 
xiii. 86, t. 12, £. 29-36 (Monographia Betulacearum) 
(1860). 
Betula alba, subsp. 6 cordifolia, Regel, Bull. Soc. Nat. 
Mose. xxxviii. pt. ii. 401 (Gattungen Betula und Alnus 
[1865]) ; De Candolle Prodr. xvi. pt. ii. 166. 
Betula papyrifera, 8 minor, Gray, Man. ed. 5, 459 (in 
part) (not Tuckerman) (1867). 
Betula papyrifera, var. minor, Watson & Coulter, Gray’s 
Man. ed. 6, 472 (1890). — Sargent, Silva N. Am. ix. 
57. — Britton & Brown, Jil. FU. i. 509. — Britton, Man. 
328. 
Betula papyracea, a cordifolia, Dippel, Handb. Laubholzk. 
ii. 177 (1892). 
On the slopes of Mt. Katahdin in Maine and on the White Mountains of New Hampshire the 
Canoe Birch is usually not more than thirty or forty feet in height, and at the highest elevations 
which it reaches on these mountains it is reduced to a low shrub. The leaves of this mountain tree 
are cordate at the base, and farther north, and in the northern Rocky Mountain region where the 
Canoe Birch is not common, the leaves are sometimes cordate and sometimes wedge-shaped at the base. 
On plate ecccli. of this work the ordinary form of the Canoe Birch with leaves broadly cuneate at the 
base is figured, and properly to illustrate this species a figure of this well-marked alpine, northern and 
western form is needed. Except in the form of the leaves, there seems to be no other constant 
characters by which the variety cordifolia can be separated from the typical Canoe Birch." 
1 A confusion which has existed in the name of this Birch is (Bull. Soc. Nat. Mosc. xxxviii. pt. ii. 404 [Gattungen Betula und 
due to the fact that two plants have been confounded in the Betula 
papyracea, var. minor, of Tuckerman, as shown by Mr. Fernald in 
his Catalogue of the Vascular Plants of Mt. Katahdin (Rhodora, iii. 
173). Mr. Fernald identifies Tuckerman’s specimens in Herb. Gray 
of Betula papyracea, var. minor (Am. Jour. Sci. xlv. 31 [1843]), 
with the plant which Regel has called Betula alba, subsp. 8 tortuosa 
Alnus] [1865] ; De Candolle Prodr. xvi. pt. ii. 168), an Old World 
plant, while American botanists previously had considered the dwarf 
form of the Canoe Birch to be Tuckerman’s plant. Regel’s name, 
cordifolia, therefore, based in part on specimens collected on Mt. 
Katahdin in 1846, should be adopted for this variety. 
