and Old World Birches. 181 



arated. Both are trees commonly with red-brown or brown- 

 gray bark, both have tlie twigs smooth or resiniferous, the 

 leaves dark green above, paler beneath and ultimately quite 

 glabrous. The fruiting catkins are described in practically 

 the same terms. B. kenaica is common in the region of 

 Kenai Peninsula and Kadiac Island ; while B. alaskana is 

 characterized as "the 'canoe birch' of all travellers in Alaska," 

 and the range given includes " the Alaskan coast on the shores 

 of Lynn Canal . . . ; and westward." Since Lynn Canal lies 

 on the coast in the same latitude as Kenai Peninsula and 

 scarcely 500 miles to the eastward, the general range covered 

 by Professor Sargent's "westward" may well include the 

 type region of Betula kenaica. 



A comparison of specimens of Betula kenaica and B, alas- 

 kana likewise fails to reveal any distinctions. For instance, 

 Coville and Kearney's 'Eo. 2,123 of B. kenaica (sheet ^o. 

 373,620 in the U. S. Nat Herb.) is quite inseparable from 

 Macoun's Prince Albert material (No. 12,952<^, Herb. Geol. 

 Surv. Can.), one of the original specimens cited for B. alas- 

 kana j and neither of these specimens can be separated in 

 habit, twigs, leaves or pubescence from No. 20,327 of the 

 Canadian Geological Survey Herbarium, material collected by 

 R. G. McConnell near Dawson City on the Yukon, where B. 

 alaskana is said to abound. Furthermore, although the Bour- 

 geau specimen of B. verrucosa^ var. resinifera^ the first cited 

 specimen of B. alaskana^ is young, its leaf -outline and very 

 resiniferous twigs seem quite identical with those of Coville 

 and Kearney's No. 2,412 of B. kenaica (sheet No. 373,618, 

 U- S. Nat. Herb.). There is, then, no question that Betula 

 alaskana described in 1901 is identical with B. kenaica^ pub- 

 hshed in 1899. 



Both Mr. Evans and Professor Sargent had their species 

 compared at St. Petersburg, before publication, with Siberian 

 material ; and it is certainly very unfortunate that these com- 

 parisons were not more satisfactorily made, since very many 

 sheets in the Gray Herbarium, as well as the United States 

 National Herbarium, sliow what appear to be identical 

 branches collected in Asia over a wide range of country, — 

 from Kamtschatka to northwestern Siberia (Yenisei Piver), 

 south to Japan, Mandschuria, Mongolia and Sungaria. This 

 Asian tree was treated by Kegel in the Prodromus as Betula 

 alba, subsp. mandshurica and latifolia, while the more 

 strongly resiniferous were included in his subsp. verrucosa, h 

 resinifera. The form treated by Kegel as subspecies lati- 

 folia had, however, been described by Siebold"^ in 1830 as 

 Betula japonica. 



* Verh. Batav. Gen., xii (1830), 25. 



