IIORDE.E. 647 



included in the upper sheath, slightly compressed, light green, soon 

 breaking when mature, eacli joint of the rachis 3 mm. long, about 

 1 mm. wide. Spikelets, including awns, 4-5 cm. long ; empty 

 glumes of the middle one lanceolate, ciliate on the margins; floral 

 glume scabrous above, flat on the back, 12-14 mm. long; palea but 

 little shorter. Stij^es of lateral spikelets 1.5 mm. long; empty 

 glumes setaceous, 2-3 mm. long; floral glumes and paleae like those 

 of the central floret. Grain flat, narrowly ellii^tical, 5,5 mm. long.- 



New Jersey (ballast-grounds), Scrihner for U. S. Dept. Agricul. 

 777. 



A native of Europe, but now widely distributed in many parts of 

 the world, rather sparingly introduced into North America. 



7. H. HEXASTiciiOK L. Sp. PI. 85 (1753). Six-eowed Barley. 

 H. heterostycliyon Beau v. Agrost. 114 (1812). 



An erect annual, 60-80 cm. high. Spikes compressed, about 

 10 cm. long, not counting the erect awns, which are often 15 cm. 

 long; rachis stout, each joint 4 mm. long, not readily separating. 

 Spikelets all sessile and all fertile; empty glumes slender, 

 bristles 1-3 cm. long; floral glume prominently nerved above, 10-12 

 mm. long, adhering to the grain. 



A well-knoAvn valuable plant, cultivated in a wider range of 

 climate than any other cereal. 



8. H. DiSTicHox L. Sp. PL 85 (1753). Two-rowed Barley. 

 Zeocriton disticlmm Beauv. Agrost. 115 (1812). H. imherhe Ar- 

 duini. R. & S. Syst. 2:793 (1817). This differs from the above 

 chiefly as follows: lateral spikelets stipitate, neutral; floral glume 

 of lateral sjjikelets obtuse, acute, or short awned. 



Often cultivated. 



144. (275). Elymus L. Sp. PI. 83 (1753). Crithopsis Jaub. & 

 Spach, Illustr. 4 : 30, f. 321 (1850). Leipmis Ilochst. Flora 31 : 118 

 (1848) in foot-note. Orthostachijs Ehrh. Beitr. 4 : 146 (1789). Po- 

 lya7itherix 'Nees, Ann. Nat. Hist. (I) 1 : 284 (183S). Sitanio)i Rafin. 

 Journ. Phys. 89: 103 (1819). Sitospelos Adans. Fam. 2: 36 (1763). 



Spikelets 2-6-flowered, 2-6 together, sessile at the nodes of the 

 more or less excavated rachis of the simple spike, rachilla articulate 

 below tlie florets, flowers perfect or the upper imperfect or reduced 



