ORDER 156. GRAMINEJS. 801 



brakes and scarcely ever fl6wer. The firm, jointed, hollow, straight and tall 

 culms are variously useful 



47. LEPTITRUS, Br. Spikelet 1 on each joint of the filiform rachis, 

 immersed in a cavity, 1 or 2-flowered ; glumes coriaceous, acute, the 

 lower often wanting; pales membranous, awnless, shorter than the 

 glumes ; grain free. Lvs. and spikes very narrow. , 



L. paniculatus Nutt. Culm scarcely If, compressed ; Ivs. short, rigid, sheathing 

 the base of the panicle ; pan. or naked rachis incurved, acutely triangular, rigid, 

 bearing 6 10 compressed, subulate spikes on one side, each 1 2' long; spike- 

 lets remote, on one side the rachis ; glumes rigidly fixed, unequal, parallel ; paleae 

 2, the outer of the same texture as the glumes, inner membranaceous. 111. (Mead), 

 Mo. (Nuttall). 



48. HOR'DEUM, E. BARLEY. (The ancient Latin name.) Spike- 

 lets 3 at each joint of the rachis, 1 -flowered, the lateral ones sometimes 

 abortive ; glumes 2, subulate, nearly equal, awned ; paleaj* 2, lower 

 lance-ovate, long-awned, upper obtusely acuminate ; caryopsis adhering 

 to the paleae. 



1 H. vnlgare L. FOUR-ROWED BARLEY. Culm smooth, 2 3f ; Ivs. lance-lin- 

 ear, carinate, nearly smooth ; sheaths auriculate at the throat ; spike thick, about 3' 

 long ; spikelets ah 1 fertile, 1 -flowered, with an awn-like rudiment at the base of 

 the upper paJea ; glumes collateral, shorter than the flowers ; fr. arranged in 4 

 rows. 2| Extensively cultivated. May. 



2 H. disticimm L. TWO-ROWED BARLEY. Culm 2 3f; Ivs. lance-linear, 

 scabrous above ; sheaths auriculate at the throat ; spike 3 i' lon^-, linear, coin- 

 pressed; lateral spikelets abortive, awnless; //*. arranged in 2 rows. f, More 

 common, and is generaUy preferred for malting to the former species. June. 



3 H. jubatum L. SQUIRREL-TAIL GRASS. Culm slender, round, smooth, simple, 

 about 2f ; Ivs. broad-linear. 4 6' long, rough-edged, otherwise smooth, as well 

 as the sheaths; spikes 23' long; spikelets with the lateral flowers neuter; 

 glumes and palea3 produced into fine, smooth awns, 6 times as long (2') as tfie 

 flowers ; abortive flowers on short pedicels. Marshes, N. Eng. to Mo., N. to 

 Subarc. Am. June. 



4 H. ptisilhim Nutt. Culm 4 6', decumbent or geniculate at the base; Ivs. 

 about 1^' long, rather obtuse, glaucous, striate; upper sheath tumid, embracing 

 the spike; spike linear, about 1^' long; glumes by 3s, collateral, imbricated, 

 lateral ; abortive fls. awnless ; awn of the central sessile $ , as long as those of the 

 involucre, twice the length (7") of the pales, glumes all awned, the inner setaceous 

 from the base. Ohio- to 111. and Mo. 



49. EL'YMUS L. LYME GRASS. WILD RYE. (Gr. eAvw, to en- 

 velop ; as the spike in the sheath.) Spikelets 2 to 4 at each joint ot' 

 the rachis, 2 to 6-flowered ; glumes 2, subequal, subulate, both placed 

 on the outer side of their spikelet forming an involucre to the group, 

 sometimes minute or obsolete ; pales lanceolate, coriaceous, the lower 

 mostly awned. 



ELYMTTS proper. Involucre present, consisting of the conspicuous glumes, 

 a Spikelets 1 to 5-flowered, hard, rough, with conspicuous awns, (b) 



(a) 



b Spikelets glabrous, inerelv rough, 2 or 3-flowered Nos. 1, 2 



b Spikelets hispid with hairs, 1 to 8, or 2 to 5-flowered Nos. 3, 4 



a Spikelets 5 to S-flowered, soft-pubescent, without awns No. 5 



GYMXOSTACUCM. Invol. obsolete or the gls. minute. Awns divaricate No. 6 



1 B. Virginicus L. Culm smooth, 3 or 4f, erect : Irs. lance-linear, flat, scabrous, 

 deep green, 4" broad; sheaths striate ; lig. very short ; spike erect, thick, 3 to 5 

 long ; spikelets in pairs, 2 or 3-jlowered, the collateral glumes in front, thickened 

 and subconnate at base, striate, and with the pales, produced into rather short (6 

 to 10"), scabrous avms. If Banks of streams, U. S. A Southern variety has 

 the glumes very thick and arcuate at base (like E. Caput-Medusa? L.). Aug. 



51 



