84 Rhodora [May 
Ontario; Lake Huron (fide Hook., Fl. Bor. Am.) ; Yellowstone. Na- 
tional Park, Montana, Idaho, Washington and Vancouver. Arctic 
and subarctic Europe and Asia. Flowering June and July ; fruiting 
July and August (mature in eastern New Brunswick, July 16, on Mt. 
Albert, Quebec, August 27). 
Var. albidum, n. comb.  Bristles white.— Æ. russeolum, var. albi- 
dum, F. Nylander, Acta Soc. Sc. Fenn. iii. (1852), & in Anders., Bot. 
Not. (1857) 58. Æ. russeolum, var. candidum, Norman, Ind. Supp. 
46 (1864) ; Hartm., Handb. ed. 11, 450 (1879).— Same range as the 
species but less common, except perhaps about Behring Sea. 
\ 
* * Caespitose, not stoloniferous: empty scales at the base of the spikelet 
numerous (usually 10-15). 
+ Flowering spikelet oblong, 1-3 cm. long: anthers 2-3 mm. long: fruiting 
spikelet subglobose or broadly obovoid, as high as broad. 
E. vaGINATUM, L. Densely caespitose, forming broad tussocks 
with very numerous stiff obtusely trigonous culms (1.5—7 dm. high): 
basal sheaths brown, long-persistent, fibrillose; basal leaves slender, 
trigonous, smooth or scabrous; cauline sheaths 2, conspicuously 
inflated above, veiny-reticulate, with dark (usually black) membra- 
nous tip: scales obovate to ovate-lanceolate, long-acuminate, lead- 
color or blackish, with whitish or pale margins: bristles glossy white. 
— Sp. 52 (1753); Engl. Bot. xiii. t. 873 (1801), ed Syme, x. 71, t 
1604 (1873); Baxter, Brit. Bot. vi. t. 427 (1843); Reich., Ic. Fl. 
Germ. viii. t. 289, fig. 686 (1846); Palla, Bot. Zeit. liv. ab. r, 148, 
151 (1896); Ostenfeld, Fl. Arct. 40 (1902); &c. Æ. caespitosum, 
Host, Gram. i. 30, t. 39 (1801).— Yukon District, White Horse 
Rapids, Yukon River, Sept. 1, 1902 (/. Macoun, Herb. Geol. Surv. 
Can. no. 53,839): Mackenzie District, Artillery Lake, May 29, 
1900 (J. W. Tyrrell, Herb. Geol. Surv. Can., no. 23,138). North- 
ern Europe and Asia, and western Greenland. 
The Tyrrell material from Artillery Lake is very fragmentary ; but 
the oblong flowering spikelets, long anthers and very inflated sheaths 
are quite like those of the Old World Æ. vaginatum. ‘The Macoun 
plant from the Yukon has the leaves harshly scabrous, a character 
unusual in the European plant, but noticeable in some Scandinavian 
specimens. Most other American material which has passed as Æ. 
vaginatum belongs to the two following species. 
