HORDE.E. 643 



stipes, one side next the rachis at the nodes or notches of a simple 

 spike. Kachilla very short, articulate above the lower glumes, 

 extending above the flower as a long slender awn or a very narrow 

 glume, flowers perfect or those of the lateral spikelets male or rudi- 

 mentary. Empty glumes subulate or lance-linear, firm, persistent, 

 the 6 at each joint appearing like an involucre; floral glume lance- 

 olate, round on the back, 5-nerved above, extended into a straight 

 or spreading awn; palea but little shorter than the floral glume, 

 2-keeled. Stamens 3. Lodicules 3, ciliate. Styles very short, 

 distinct. Grain ovoid-oblong or narrow, hirsute at the apex, 

 grooved on the inside, adhering to the palea or rarely free. Erect 

 annuals or rarely perennials, with flat leaf-blades. Spike cylindri- 

 cal, usually densely flowered with long, or rarely short awns. 



Species 12-lG, indigenous to Europe, north Africa, temperate 

 Asia, North and South America. 



Beauvois restricted Hordeum to the common cultivated barley, 

 which appears in a great variety of forms. The genus, as here 

 understood, is distinguished from Elymus by the single flower in 

 each spikelet, and is distributed into three sections : 



1. ZcocritoH Beauv. Central spikelet alone of each three is 

 fertile, the lateral ones sterile or I'educed to empty glumes. 



2. Crithopsis Jaub. Two perfect spikelets at each notch, the 

 intermediate one deficient or rarely represented by one or two 

 empty glumes. 



3. Olivier a Koel. Spikelets 3 and collateral, all fertile. 



A. Not in cultivation (a) 



B. Cultivated for grain. ............ (e) 



a. Awns 4-6 cm. long 1 



a. Awns 3 cm. long or less (b) 



b. Empty glumes 0.5-0.7 mm. wide, uj^per blades 1- 



3 cm. long 3 



b. Empty glumes 0.3-0.5 mm. wide, upper blades 10- 



15 cm. long 2 



b. Empty glumes narrower (c) 



c. Spike 7 mm. wide 3 



c. Spike wider (d) 



