Order 156.— GRAMINEjE. 801 



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

 culms are variously useful. 



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

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

 lower often wanting; pales membranous, awn less, shorter than the 

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



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

 the base of the paniclo ; 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 ; paleso 

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

 Mo. (Nuttall). 



48. KOR'DEUM, E. Barley. (The ancient Latin name.) Spike- 

 lets 3 at each joint of the rachis, 1-flowcred, 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 palcsa. 



1 H. vxilgare L. Four-rowed Barley. Culm smooth, 2 — 3f; lvs. lance-lin- 

 ear, carinate, nearly smooth ; sheaths auriculate at the throat ; Gpike 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. — 11 Extensively cultivated. May. 



2 H. distichum L. Two-rowed Barley. Culm 2 — 3f; lvs. lance-linear, 

 scabrous above ; sheaths auriculate at the throat ; spike 3 — 4' long, linear, com- 

 pressed ; lateral spikelets abortive, awnless ; //•. arranged in 2' rows. — J) Moro 

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



3 II. jubatum L. Squirrel-tail Grass. Culm slender, round, smooth, simple, 

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

 as the sheaths; spike3 2 — 3' long spikelets with the lateral flowers neuter; 

 ghinie3 and paleas produced into line, smooth awns, 6 limes as long (2') as (he 

 /lowers ; abortive flowers ou short pedicels. — © Marshes, N. Eng. to Mo., N. to 

 Subarc. Am. June. 



4 II. pusiliuni Nutt. Culm 4 — C, decumbent or geniculate at the base; lva. 

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

 the spike; spike linear, about \\' 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. eXvo), 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 spikelct forming an involucre to the group, 

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

 mostly awned. 



§ Eltmus 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 8-flowere<l Nos. 1, 2 



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



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



§ Gymnostacuum. Invol. obsolete or the gls. minute. Awns divaricate No. 6 



1 E. Virginicns L. Culm smooth, 3 or 4f, erect; lvs. lance-linear, flat, seabroua, 

 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 (& 

 to 10"), scabrous aimis. — If Banks of streams, U. S. A Southern variety baa. 

 the glumes very thick and arcuate at base (like E. Caput-Medusse L.). Aug. 4 



51 



