Till-: (iKASHKS OK Tknnksskk. 126 



Annual or perennial grasses with terniinal cylindrical spikes and 

 awned spikelets. Species about sixteen, in both hemispheres. 



I Hordeum pratense Huds. Wild Barley. 

 Plate Xr.V. FijJTure 1H(J. 



A slender grass, six to twenty-four inches high, with rather 

 sh'»rt, flat leaves, and narrow terminal spikes one to three inches 

 lon^^'-. Culm usually geniculate at the lower joints; sheaths and 

 'eaves smooth or pubescent. Empty glumes all setaceous; lateral 

 spikelets imperfect, the awn-pointed florets pedicellate within 

 their glumes; floret of the central spikelet perfect, cylindrical, 

 three to four lines long, awned; awn three to six lines long. Ra- 

 chis of the spike readily breaking up at the joints. Not uncom- 

 mon on thin soils. May. 



This grass has the habit of an annual, and is apparently of no 

 agricultural value. 



2. Hordeum pusillum Xutt. 



Plate XLVI. Figure 181. 



An annual four to ten inches high. Culms more or less genicu- 

 late at the lower nodes. Sheaths smooth, the uppermost often in- 

 flated and enclosing the base of the spike; leaf-blade one to three 

 inches long, usually a little pubescent on the lower surface. Spikes 

 narrow, one to three inches long. Empty glumes rigid, the four 

 internal ones of each group dilated above the base, those of the 

 central spikelet sublanceolate, all awn-pointed; outer glume of the 

 imperfect lateral spikelets setaceous. Flowering glume of the 

 central spikelet awned; awn about equalling those of the empty 

 glumes. Florets of the lateral spikelets awnless, or nearly so. 



In similar situations to the last, which it resembles, but from 

 which it is readily distinguished by the dilated empty glumes. 



3. Hordeum vulgare Linn. Barley. Four-rowed Barley. 



Annual , two to three feet high, smooth. Leaves linear-lanceolate, 

 keeled, nearly smooth; sheaths striate, smooth, auricled at the 

 throat; ligule very short. Spikes three to four inches long, some- 

 what four-sided, rachis flattened, pubescent on the margins. Spike- 

 lets with one perfect floret; empty glumes narrowly linear, pubes- 

 cent, terminating in a slender awn; flowering glume five-nerved, 

 scabrous near the apex, long-awned; awn flattened, keeled, some- 

 what three-nerved, serrulate on the margins. 



Cultivated chiefly for malt for brewing. 



In Hordeum distichum^ or Two-rowed Barley, the florets of the 

 lateral spikelets are staminate or neuter, and awnless; the spikes 

 linear and compressed. 



63. ELYMUS Linn. Sp. PI. Zz (1753). 



Spikelets two- to six-flowered, the uppermost imperfect, sessile, 

 in pairs (rarely in threes or fours) at the alternate notches of the 

 continuous or articulate rachis, forming terminal spikes; rachilla 



