1917] Butters,— Studies in Ferns — Athyrium 193 
ATHYRIUM ANGUSTUM var. rubellum (Gilbert), new comb." 
. Athyrium filia-foemina rubellum Gilbert, List of N. A. Pterid. 35 
1901). 
In the southern part of its range this variety appears to be merely 
the shade-form corresponding to the sun-forms discussed above, 
especially to the var. elatius, and its fronds are scarcely to be dis- 
tinguished from the sterile fronds of that variety. The variety 
rubellum, however, ranges much farther to the north and east than 
either forma typicum or var. elatius, which appear never to occur in 
regions of cool summers. 
The variety rubellum occurs throughout the range of the species, 
of which it appears to be the fundamental biological type, from which 
all the other varieties and forms have been derived. As here defined, 
it is not limited to forms with red stems, and hence it is unfortunate 
that we are obliged to adopt Gilbert’s name. This is necessary, as 
authentic material of Gilbert’s variety, collected by Gilbert himself, 
from his type locality, unquestionably belongs to the variety as here 
defined. 
The following are the specimens of this variety in the Gray Her- 
barium: 
NEWFOUNDLAND: barrens at the base of the serpentine tablelands, 
region of Bonne Bay; August 27, 1910, Fernald and Wiegand no. 
2319; rocky border of hillside brook, Snook’s Arm, Notre Dame Bay, 
August 19, 1911, F ernald and Wiegand no. 4284; Blow-me-down 
Mts., 1300 ft. altitude, August 4, 1908, Eames and Godfrey no. 5763; 
woods, Bay of Islands, August 9 and 10, 1901, Howe and Lang no. 
1179; dry thicket, Bay St. George, August 5-7, 1901, Howe and Lang 
no. 989. 
Quesec: low wet margin of Seal Cove River, Douglastown, Gaspé 
Co., August 22, 1904, Collins, Fernald and Pease; Bic, Rimouski Co., 
July 15, 1907, Fernald and Collins no. 817; Cap à l’Aigle, July 13, 
1905, John Macoun, herb. Geol. Surv. Canada no. 69251; Little 
Metis, August 21, 1906, James F owler. 
Prince Epwarp Istanp: roadsides thickets and borders of dry 
woods, August 29, 1912, F ernald, Long and St. John no. 6664. 
New Brunswick: in partial shade along a fence, Shediac Cape, 
August 2, 1914, F. T. Hubbard. . 
Nova Scotia: Baxter’s Harbor, July 10, 1900, F. G. Floyd no. 680; 
rich soil, edge of woods, Pictou, July 12-18, 1901, Howe and Lang no. 
547, dry woods, Pictou, July 12-18, 1901, Howe and Lang no. 546; 
rich moist bank, Yarmouth, June 22-29, 1901, Howe and Lang no. 111; 
Kentville, July 11, 1900, F. G. Floyd no. 686. 
Marne: rich woods, Canton, August 1, 1908, J.C. Parlin. 
New Hampsutre: woods, Randolph, July 7, 1894, E. F. Williams. 
Alton Bay, A. A. Eaton; low woods, Jaffrey, July 21, 1897, B. L. 
1 See Plate 123, figure 13. 
