174 Fernald — Relationshi'ps of some American 



The original material of Betula occidentalis came from the 

 Strait of Juan de Fuca ; and if we examine specimens from 

 that region we shall find them matching in every character of 

 pubescence, leaves and strobiles large forms of eastern B. alba 

 {B. ^apyrifercC)^ 2i^ already intimated by Professor Sargent.^ 

 Branches collected by Professor L. F. Henderson in 1888 on 

 the Gulf of Georgia, essentially a continuation of the Strait of 

 Juan de Fuca, are clearly B. occidentalism as shown by a trac- 

 ing at the Arnold Arboretum of the original Scouler specimen. 

 These specimens from the Gulf of Georgia have some of the 

 branchlets strongly hirsute with sordid liairs mixed with abun- 

 dant resiniferous atoms, while other (perhaps older) branchlets 

 appear quite glabrous. In the original description of B. occi- 

 dentalism Hooker emphasized the abundance of resin, though 

 nothing was said of hairs upon the branchlets. This character, 

 however, is extremely variable, as shown by a large suite of 

 specimens from Washington and British Columbia ; and, ad- 

 mitting this inconstancy in the amount of resin and pubes- 

 cence, the Gulf of Geoi'gia branches seem to the writer quite 

 inseparable from many sheets representing B. alba {B. papyri- 

 ferd) from different sections of America. In such characters 

 as are shown in herbarium material they are identified with the 

 following among other specimens : Almota Creek, Whitman 

 Co., Washington {^Piper^ ISo. 3,570), very resiniferous but not 

 hairy, thus matching the original description ; Cascade Mts. 

 and Sumass Prairie, lat. 49°, British Columbia {Lyall), the 

 latter the type of B. alba, subsp. occidentalism /3, commutata, 

 Kegel, the branchlets resiniferous but not hairy, thus agreeing 

 with Hooker's original description ; Pend cl' Oreille Piver, 

 Washington (Zyall), branchlets quite as hairy as in the Gulf 

 of Georgia tree ; Hill City, South Dakota ( F. Bailey, sheet 

 No. 230,000, IJ. S. Nat. Herb.), branchlets hairy ; Black Hills, 

 South Dakota {Rydberg, No. 1,005), branchlets hairy ; Queens- 

 town Heights, Ontario {3£acounm Herb. Geol. Surv. Can., No. 

 23,636), branchlets resiniferous, hirsute at tips ; Goat Island, 

 Niagara Falls, New York {Coville, sheet No. 294,829, U. S. 

 Nat. Herb.), branchlets puberulent ; Bald Eagle Ridge. Center 

 Co., Pennsylvania {Porter), branchlets as in Gulf of Georgia 

 specimens ; North Conway, New Hampshire ( Win. Boott), 

 branchlets as in last ; Mountain Rock, Ellsworth, Maine {Fer- 

 nald), branchlets resiniferous, slightly hairy ; Manuels, New- 

 foundland (Robinson and Schreiik, No. 139), branchlets as in 

 last. Other specimens from the coastal region of Washington 

 and British Columbia are quite like some eastern branches. 

 Thus Lake and Hull's plant from Tukanon River, Washington, 

 and Macoun'sNo. 23,639 from Vancouver, are inseparable from 



*Silva, 1. c, Bot. Gaz., 1. c. 



