GRASSES OF SCOTLAND. 31 



18. HORDEUM PRATENSE. * 



Meadow Barley. 



Specific Characters. — All the gliimes bristle-shaped. (Plate XI.) 



Description. — It grows from eighteen inches to two feet or more 

 high. The root is perennial, fibrous, (" becoming bulbous in bar- 

 ren ground, occasionally overflowed,*' Smith.) Stem roimd, smooth, 

 erect, and glossy ; bearing four or five leaves with smooth striated 

 sheaths ; the upper sheath longer than its leaf, crowned with a very 

 short ligule. Joints smooth. Leaves linear, flat, acute, roughish, 

 and somewhat hairy on both surfaces, the edges minutely serrated. 

 Inflorescence spiked. Spike about an inch and a-half in length, dense 

 and uniform : the rachis jointed, very brittle, toothed alternately on 

 each side, the intermediate spaces flattened and bordered. Spikelets 

 arranged in threes on each tooth of the rachis ; of one-awned floret. 

 Calyx of the central spikelet of two bristle-shaped glumes (Fig 1) 

 of equal length. Central jioret of two paleae, the outer palea three-rib- 

 ed, terminating in a long, rough awn, rather longer than the palea ; 

 inner palea acute, with a delicate bristle at the base, about half the 

 length of the palea. Lateral spikelets pedunculated, the glumes bris- 

 tle-shaped, (Figs. 2 and 3), rough. Lateral Jioret imperfect, furnish- 

 ed with a short awn, not as long as the palea ; occasionally the awn 

 is altogether wanting. 



Obs. — Hordeum pratense is distinguished from Hordeum murinum 

 in being of a taller and more slender habit, with the awns of the spike- 

 lets shorter ; the glumes of the middle spikelet bristle-shaped, and 

 not fringed ; Jiorets of the lateral spikelets with very short awns ; — 

 whereas in H. murinum the glumes of the middle spikelet are dilated 

 and fringed, and the Jiorets of the lateral spikelets with very Ion**- 

 awns. (Fig. 4.) 



From Hordeum maritimum, in being of a taller and more slender 

 habit ; all the ghimes bristle-shaped (Fig. 2.) ; — whereas in H. mari- 

 timum the inner glume of the lateral spikelet is dilated on one side, 

 in the form of half-ovate. (Fig. 2.) 



Although this grass produces a tolerable e^rly spring crop of foli- 



" Hordeum pratensc, Smith, Hooker, Lindley. Hordeum nodosum, Koch. 



