ORDER 156. GRAMINE^E. 801 



brakes and scarcely ever flower. Tho firm, jointed, hollow, straight and tall 

 culms are variously useful 



47. LEPTITRUS, Br. Spikelet 1 on cacli 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. 



I*, paniculattis 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 ; paleas 

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

 Ma (Xuttall). 



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. vulgare L. FOUR-HOWED BARLEY. Culm smooth, 2 3f; Ivs. lance-lin- 

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

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

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

 rows. 2+ Extensively cultivated. May. 



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

 scabrous above ; sheaths auriculate at the throat ; spike 3 1' long-, linear, com- 

 pressed; lateral spikelets abortive, awnless; fr. arranged in 2 rows. Q More 

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



3 H. jubattim 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 2 3' long spikelets with the lateral flowers neuter; 

 glumes and palea? produced into fine, smooth awns, 6 times as long (2') 05 the 

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

 Subarc. Am. June. 



4 H. pusilhim Kutt. Culm 4 G', decumbent or geniculate at the base; Ivs. 

 about !' 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 ihe pales, glumes all awned, the inner setaceous 

 from the base. Ohio to 111. and Mo. 



49. EL'YMUS L. LYME GRASS. WILD RYE. (Gr. eAvo), to En- 

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

 the rachis, 2 to 6-fiowered ; 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. 



ELYMUS proper. Involucre present, consisting of the conspicuous glumes (a) 

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



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



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



a Spikelets 5 to 8-flowered, soft-pubescent, without awns No. 5 



GYMNOSTACUUM. luvol. obsolete or the gls. minute. Awns divaricate No. '6 



1 B. Virginicns L. Culm smooth, 3 or 4f, erect ; Ivs. lance-linear, flat, scabrous, 

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

 long ; spikekts in pairs, 2 or 3-fiowered, the collateral glumes in front, thickened 

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

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

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



51 



