Gymnopogon. a G. racemosum, branch, n. m. b Glumes, c Pales, d G. fil-iformis, branch, n. m. e Spikelet m. d Spikelet closed.

Cynodon. a C. Dactylon, dim. c Spikelet in flower, b Portion of spike. d Glumes.

Eleusine. a E. Indica, n. m. b Spikelet m. c Spikelet in fruit.

Spartina. a S. polystachia, branch, n. m. b Spikelrt. c Flower without the pales.

Bouteloua. c B. curtipendula, n. m. a Spikelet. b B. hirsuta, spikelet. d The abortive flower.

Tripsacum. a T. dactyloides, n. m.,Illustrating The Genera Of Gramineae Part 2 2645 pistillate flowers. Illustrating The Genera Of Gramineae Part 2 2646 staminate flowers.

ROTTBŒLIA. b, R. rugosa, n. m. c A joint of the spike with one sessile, fertile spikelet, and one pedicelled, abortive spikelet.

STENOTAPHRUM. c S. dimidiatum, under side of the spike.

Ctenium. a C. aromaticum, n, m, b Spikelet in fruit.

Erianthus. a E, alopecuroides, a joint of the rachis and spikelet, n. m. b Spikelet m,, in fruit, c E. brevibarbis, spikelet and joint of rachis, n. m, brakes and scarcely ever flower. The firm, jointed, hollow, straight and tall culms are variously useful.

Andropogon. a A. scoparius, several 6pikelets, n. m. b One spikelet, m., with a joint of rachis, c A. Halei, 2 spikelete, n, m. d Spikelet, m., with a joint of rachis.

Zea. a Spikelet, stamiuate, from the tassel. b Spikelet, pistillate and fertile, from the ear, with its long style.

47. LEPTU'RUS, 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; lvs. 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. - Ill. (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; paleae 2, lower lance-ovate, long-awned, upper obtusely acuminate; caryopsis adhering to the paleae.

1 H. vulgare L. Four-rowed Barley. Culm smooth, 2 - 3f; lvs. lance-lin-car, carinate, nearly smooth; sheaths auriculate at the throat; spike thick, about 5' 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. -Illustrating The Genera Of Gramineae Part 2 2647 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, con-pressed; lateral spikelets abortive, awnless; fr. arranged in 2 rows. -Illustrating The Genera Of Gramineae Part 2 2648 More common, and is generally preferred for malting to the former species. June.

3 H. 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; spikes 2 - 3' long spikelets with the lateral flowers neuter; glumes and paleae produced into fine, smooth awns, 6 times as long (2') as the flowers; abortive flowers on short pedicels. - Marshes, N. Eng. to Mo., N. to

Illustrating The Genera Of Gramineae Part 2 2649

Subarc. Am. June.

4 H. pusillum Nutt Culm 4 - 6', decumbent or geniculate at the base; lvs. about 1 1/2' long, rather obtuse, glaucous, striate; upper sheath tumid, embracing the spike; spike linear, about l 1/2' long; glumes by 3s, collateral, imbricated, lateral; abortive fls. awnless; awn of the central sessileIllustrating The Genera Of Gramineae Part 2 2650 , 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 Ill. and Mo.

49. EL'YMUS L. Lyme Grass. Wild Rye. (Gr.Illustrating The Genera Of Gramineae Part 2 2651 to envelop; as the spike in the sheath.) Spikelets 2 to 4 at each joint of 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.

§ 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, 1to 3, or 2 to 5-flowered.....................................

Nos. 3, 4

a Spikelets 5 to 8-flowered, soft-pubescent, without awns....................................

No. 5

§ GYMNOSTACHUM. Invol, obsolete or the gls. minute. A wns divaricate.........

No. 6

1 E. Virginicus L. Culm smooth, 3 or 4f, erect; lvs, lance-linear, flat, scabrous, deep green, 4" broad; sheaths striate; lig. very short; spike erect, thick, 3 to 6' long; spikelets in pairs, 2 or 3-flowered, the collateral glumes in front, thickened and subconnate at base, striate, and with the pales, produced into rather short (6 to 10"), scabrous awns. -Illustrating The Genera Of Gramineae Part 2 2652 Banks of streams, U. S. A Southern variety has the glumes very thick and arcuate at base (like E. Caput-Medusae L.). Aug.

2 E. Europaeua L. Culm erect, 3 to 5f, lvs. lance-linear, scabrous, with somewhat hairy sheaths; spike suberect, 5 to 8', very scabrous but nearly glabrous; spikelets ternate, 2-flowered, with long (15 to 25"), stout, straight, diverging awns all of similar length. - Along rivers, S. States. The long parallel awns give it quite a different appearance from No. 3.

3 E. Canadensis L. Culm erect, 3 to 5f; lvs. lance-linear, flat, smooth, dark green, or often glaucous; spike rather loose and spreading, 4 to 8' long, generally nodding, rachis hairy, spikelets more or less hairy, in 2s and 3s, 3 to 6-flowered, awns of the fls. usually curved, longer (7 to 17") than those of the glumes. - A tall grass, looking like Rye, with long, recurved, waving spikes. River banks. Aug.