294 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



28. HORDEUM L. Barley grass. 



Perennial bunchgrasses (in this region) with flat blades and dense bristly spikes, 

 the axis readily disjointing. 



Awns 4 to 6 cm. long 1- H. jubatum. 



Awns about 1 cm. long or less 2. H. nodosum. 



1. Hordeum jubatum L. Squirreltail. Common at low and middle altitudes, 

 in meadows or prairie. Alaska to Calif., Tex., N. J., and Lab. — Culms erect or 

 spreading, 30 to 50 cm. tall, with pale nodding spikes 5 to 10 cm. long, the slender 

 awns widely spreading. 



2. Hordeum nodosum L. East entrance, on wet prairie. Alaska to Calif, and 

 Tex.; also in Eur.— Culms often geniculate at base, 30 to 60 cm. tall, with slender 

 spikes 3 to 10 cm. long and scarcely 1 cm. wide. 



29. ELYMUS L. Wild rye. 



Tall, erect, rather coarse perennials with flat blades and bristly spikes, the axis 

 not disjointing. 

 Spikelets awnless. Glumes subulate. 



Plants with long creeping rootstocks; spike relatively loose, some of the joints 

 with a single spikelet 1- E. triticoides. 



Plants without rootstocks or with very short ones; spike dense, with 2 to 4 spikelets 



at a joint 2. E. condensatus 



Spikelets awned. 



Awns erect or nearly so 3. E. glaucus; 



Awns strongly divergent 4. E. canadensis. 



1. Elymus triticoides Buckl. Reported by Jones from Blackfoot Glacier. Wash. 

 to Calif., N. Mex., and Alta. — Culms rather wiry; blades involute toward the apex 



spike mostly 8 to 15 cm. long; lemmas commonly brownish, very smooth. 



2. Elymus condensatus Presl. East entrance, on prairie and open slopes. B. C. 

 to Calif., N. Mex., and Nebr.— Plants in large clumps, robust; blades elongate, 5 to 

 12 mm. mde; spikes 12 to 20 cm. long, 15 to 20 mm. thick; lemmas pale, more or 

 less scabrous. 



3. Elymus glaucus Buckl. At low and middle altitudes, on open slopes, in woods, 

 or along streams. B. C. to Calif., N. Mex., and Mich.— Culms often geniculate at 

 base; blades lax, spreading; spike erect or nearly so, the slender awns 1 to 2 cm. 

 long. 



4. Elymus canadensis L. Belton, in low flat- woods, scarce. B. C. to N. Hex., 

 Ga., and N. S.— Culms in large clumps; blades rather thick; spikes drooping, often 

 grayish, the flexuous divergent awns 2 to 4 cm. long. 



14. CYPERACEAE. Sedge Family. 



Grasslike perennials with usually solid stems; leaves 3-ranked, narrow (sometimes 

 reduced to a sheath), the sheaths close; flowers small, in spikelets; perianth of 

 bristles or sacklike; fruit an achene.— The species of this family are difficult to 

 distinguish, but in Glacier Park they are not numerous, except in the genus Carex. 



Achene inclosed in a sacklike perianth (perigynium) 5. CAREX. 



Achenes not inclosed, the perianth consisting of bristles. 

 Bristles of the perianth very long (much longer than the scales) and silky, white or 



brown 1- ERIOPHORTTM. 



Bristles very short and inconspicuous. 



Stem with only one spikelet, not leafy 2. ELEOCHARIS. 



Stem with few or many spikelets, often leafy. 



Stems hollow; spikelets flat, linear, the scales 2-ranked ... 3. DULICHIUM. 

 Stems solid; spikelets not flattened, broad, the scales spirally arranged. 



4. SCIRPTIS. 



