GRAMINE^E. (GRASS FAMILY.) 425 



* 



cent,- ligule a dilate fringe : panicle 3 to 6 inches long, the lower rays distant in 

 pairs ; spikelet 4 to 6-flowered : flowering glume 5-nerved, rough, with a narrow 

 scarious margin, pointed, or with an awn a line long or less. F. Thurberi, Vasey. 

 Melica Hallii, Vasey, is an alpine form. In the Rocky Mountains and 

 westward. One of the most valuable of the numerous " Bunch Grasses." 



45. B BOM US, L. BROME GRASS. 



Coarse grasses, with large spikelets at length drooping, on pedicels thick- 

 ened at the apex. Our indigenous species are perennials. 



* Flowering glume convex or keeled on the back: flowers imbricated over one 

 another before expansion : lower glume 3 to 5-nerved, the upper 3 to 9-nervedJ- 



1. B. Kalmii, Gray, var. Porteri. Stem 12 to 18 inches high, smooth: 

 sheaths and leaves minutely scabrous : panicle 6 inches long, compound, branches 

 minutely downy ; spikelets an inch long, canescent with short oppressed silki/ 

 hairs, 7 to 9-flowered : outer glumes each 3-nerved, obtuse : flowering glume 

 7 -nerved; its awn 1| lines long Colorado, at Twin Lakes (Porter), Buffalo 

 Peaks, and Sierra Madre Range (Coulter). 



2. B. breviaristatUS, Thurb. Stem 2 to 3 feet high: leaves broadly lin- 

 ear, a little hairy ; sheaths hairy to villose-tomentose, sometimes even naked : 

 panicle elongated, 3 to 8 inches long, nearly simple, loose ; spikelets about 

 an inch long, lanceolate, compressed and sharply 2-edged, minutely scabrous, 6 to 

 8-flowered : outer glumes acute, lower about 5-nerved, upper S-nerved : flowering 

 glume acutely keeled, 9-nerved, with an awn 1 to 2 lines long. Ceratochloa bre- 

 viaristata, Hook. From Colorado northward to Montana and Washington 

 Territory. 



* * Flowering glume somewhat convex, but keeled on the back: flowers soon sepa- 



rating from each other: lower glume \-nerved, the upper 3-nerved t or with an 

 obscure additional pair. 



3. B. ciliatus, L. Tall, 3 to 5 feet high, with the large leaves smooth 

 or somewhat hairy ; sheaths often hairy or densely downy near the top : pani- 

 cle compound, very loose, the elongated branches at length drooping ; spikelets 

 7 to 12-flowered : flowering glume tipped with an awn to f its length, 

 7-nerved, silky with appressed hairs near the margins, smooth or smoothish 

 on the back. Across the continent and far northward. 



46. AGROPYRUM, Beauv. 



Perennials, with nearly lanceolate glumes, and 2-ranked spikes ; thus differ- 

 ing from Triticum (Wheat), although formerly included under that genus. 



* Multiplying by long jointed creeping rootstocks : awn, when present, not longer 



than the flowering glume. 



1 . A. repens, Beauv. Stems 1 to 3 feet high : leaves flat or convolute 

 and with sheaths very variable, from smooth to scabrous or pubescent : spike- 



1 The too common " Cheat" or "Chess," B. secalinus, L., belongs to this section. It is 

 an annual, with spreading panicle, oblong-ovate turgid smooth spikelets of 8 to 10 rather 

 distant flowers, flowering glume short-awned or awnless, and nearly glabrous sheaths. 

 Introduced wherever grain is cultivated. 



