204 Rhodora [SEPTEMBER 
ful search has failed to disclose any. vestige of indusium in the Ameri- 
can material. 
As certain intermediate forms occur, it is the opinion of the author 
that this plant should be considered a distinct geographical variety 
rather than a species. 
ATHYRIUM ALPESTRE (Hoppe) Rylands ex Moore var. americanum, 
var. nov., omnibus frondium segmentis iisdem formae typicae angus- 
tioribus, inter se plus distantibus ultimis linearibus, soris minutis 
(0.5-0.7 mm. latis) rotundis submarginalibus, soris singulis dente 
marginali pinnulae everto tectis, velo nullo. 
This variety is found in subarctic and high alpine situations from 
Alaska and British Columbia to California and Colorado, also in Gaspé 
Co., Quebec. 
The following specimens of Athyrium alpestre var. americanum are 
in the Gray Herbarium: 
QuEBEC: forming extensive areas in the alluvium of alpine brooks, 
easterly and northerly slopes, Table-top Mt. Gaspé Co., August 9, 
1906, Fernald and Collins no. 15la; (specimens 9 dm. tall; crevices 
of granite rock, altitude 750-1050 m., easterly and northerly slopes 
Table-top Mt. Gaspé Co., August 9, 1906, Fernald and Collins no. 151. 
Montana: altitude 5500-6000 ft., Glacier Basin below Sperry 
Glacier, August 5, 1901, F. K. Vreeland no. 1058. 
IpaHo: moist places, Packsaddle Peak, Kootenai Co., August 6, 
1892, Sandberg, McDougal and Heller, no. 858. 
Wyomīne: in glacial drift, Teton Mts., July 26, 1901, Merrill and 
Wilcox no. 1032. 
CoLoraDo: rocky slopes and rock crevices, summit of North Park . 
Range, Larimer Co., August 10, 1903, L. N. Goodding no. 1841. 
CALIFORNIA: near summit of Mt. Rose, 8600 ft. altitude, 1877, 
J. G. Lemmon no. 1160; 7500 ft. altitude, Mt. Shasta, August 17, 1881, 
C. G. Pringle; 7800 ft. altitude, Mt. Shasta, August 16, 1903, E. B. 
Copeland (distributed by C. F. Baker) no. 3917; Mt. Shasta, 1877, 
Hooker and Gray; Mt. Shasta, 1897, W. M. Canby no. 414. 
WasHinGTon: loose rock, 6000 ft. altitude, Mt. Rainier, August, 
1895, C. V. Piper no. 2111; Mt. Rainier, August 1890, E. C. Smith. 
British CoLUMBIA: mountains near Ainsworth, Kootanie Lake, 
altitude 6000 ft., July 10, 1890, John Macoun; altitude 5500 ft., 
Fish Creek Valley, August 1906, Butters and Holway; on dry rocks, 
near top of Mt. Cheops [near Glacier], altitude 8200 ft., July 12, 1904, 
E. R. Heacock in Shaws Selkirk Flora no. 453; altitude 4400 ft., 
Rogers Pass, August 23, 1904, E. R. Heacock in Shaw’s Selkirk Flora 
no. 554; Selkirk Range, August 24, 1885, John Macoun; Cascade Mts. 
49° N. lat., 1859, Dr. Lyall: 
ALASKA: mountains, interior of Unalaska, October 10, 1871, M. 
W. Harrington. 
