GRAMINEAE. 1 55 



lets. Empty scales rigid; flowering scales rounded on the back, 5 -nerved at the 

 apex, awned; palet scarcely shorter than the scale, 2-keeled. Stamens 3. Styles 

 very short, distinct. Grain usually adherent to the scale, hairy at the summit. 

 [Latin name for barley.] About 20 species, widely distributed in both hemi- 

 spheres. 



Flowering scales, exclusive of awn, 6-8 mm. long. 

 Awn of the flowering scale 1.25 cm. long or less. 



All the empty scales of each cluster bristle-like. i. H. nodosum. 



Four of the empty scales of each cluster dilated above the base. 



2. H. pusillum. 



Awn of the flowering scale 2.5 cm. long or more. 3. H. jubatum. 



Flowering scales, exclusive of awn, about 1.2 cm. long. 4. //. murinum. 



1. Hordeum nodosum L. MEADOW BARLEY. (I. F. f. 529.) Culms 1.5-6 

 dm. tall, erect, or sometimes decumbent; leaves 3.75-12.5 cm. long, 2-6 mm. 

 wide, flat, rough; spike 2.5-8.5 cm. in length; spikelets usually in 3's, the central 

 one containing a palet and perfect flower, the lateral enclosing a staminate or rudi- 

 mentary flower, or a palet only; empty scales of each cluster awn-like; flowering 

 scale of the central spikelet 6-8 mm. long exclusive of the awn, which is 6-12 mm. 

 long, the corresponding scale in the lateral spikelets much smaller and short-stalked. 

 In meadows and waste places, Ind. to Minn., Br. Col. and Alaska, south to Tex. 

 and Cal. Also in Europe and Asia. June -July. 



2. Hordeum pusillum Nutt. LITTLE BARLEY. (I. F. f. 530.) Culms 1-4 

 dm. tall, erect, or decumbent at the base; leaves 1.25-7.5 cm. long, 1-4 mm. wide, 

 erect, smooth beneath, rough above; spike 2.5-7.5 cm. in length; spikelets usually 

 in 3*5, the central one containing a palet and perfect flower, the lateral imperfect; 

 scales awned, the empty ones scabrous, those of the central spikelet and the lower 

 ones of the lateral spikelets dilated above the base; flowering scales smooth, that of 

 the central spikelet 6-8 mm. long, short-awned, the corresponding scale in the 

 lateral spikelets smaller and very short-stalked. In dry soil, Ont. to Br. Col., 

 south to Neb., Ark., Tex. and Cal.; also sparingly introduced along the coast from 

 Va. to Fla. June-July. 



3. Hordeum jubatum L. SQUIRREL-TAIL GRASS. (I. F. f. 531.) Culms 

 2.5-7.5 dm. tall; leaves 2.5-12.5 cm. long, 2-4 mm. wide, erect, rough; spike 5-10 

 cm. in length; spikelets usually in 3*3, the central one containing a palet and per- 

 fect flower, the lateral imperfect; empty scales consisting of slender rough awns 

 2.5-6.25 cm. long; flowering scale of the central spikelet 6-8 mm. long, scabrous 

 at the apex, bearing a slender rough awn 2.5-6.25 cm. long; the corresponding 

 scale in the lateral spikelets short-awned, about 6 mm. long including its pedicel, 

 sometimes reduced to a rudiment. In dry soil, Ont. to Alaska, south to Kans., 

 Colo, and Cal. Naturalized in the east from Lab. and Quebec to N. J. and Penn. 

 July-Aug. 



4. Hordeum murinum L. WALL BARLEY. (L F. f. 532.) Cuims 1.5-6 

 dm. tall, erect, or decumbent at the base; leaves 2.5-15 cm. long, 2-6 mm. wide, 

 rough; spikes 5-10 cm. in length; spikelets usually in 3's; scales awned, the 

 empty ones awn-like, scabrous, those of the central spikelet broader and ciliate on 

 the margins, bearing awns 1.8-2.4 cm - l n g> those of the lateral spikelets similar, 

 with the exception of the second scale, which is not ciliate ; flowering scales sca- 

 brous at the apex, bearing an awn about 2. 5 cm. long, those of the lateral spikelets 

 about 1.2 cm. long, the corresponding scale in the central spikelet somewhat 

 smaller. On ballast and sparingly in waste places, southern N. Y. and N. J. to 

 D. C. Also from Ariz, to Cal. Adventive or naturalized from Europe. June- 

 July- 



ioo. SITANION Raf. 



Tufted grasses with flat or involute leaves and a terminal dense spike with the 

 rachis articulated and readily breaking up. Spikelets numerous, in 2's or 3*3 at 

 each joint, 1-5 -flowered; empty scales entire or divided, the divisions extending 

 often to the base, the scales or their divisions bearing long slender awns; palet 2- 

 keeled. Stamens 3. Styles distinct, short. Stigmas plumose. Grain adherent 

 to the palet. [Greek, the meaning obscure.] Usually considered a monotypic 

 genus, but probably divisible into a number of species. 



