Ordeb 156.— GEAMINE^. Y91 



highly important grain, one of the staple productions of the soil ; said to have 

 bean first discovered in the Island of Juan Fernandez. 



)3. NIGRA. Black Oats. Falece dark brown, almost black, awnlesa. 



y. SEOUKDA. HOESE-MANE Oats. Poraic^e 1-sided; at«?w short. 



29. TRISETUM, L. (Lat. iria, three, setum, a bristle ; a character- 

 istic term.) Spikclet 2 — 5-flowered ; glumes 2, shorter than the 

 flowers ; lower palea with 2 bristles at the apex and a soft, flexuous 

 awn from above the middle of the back; scales ovate; fruit coated, 

 furrowed. — Very closely related to Avena. 



1 T. pallistre Torr. Culm erect, contracted at the nodes, slender, smooth, about 

 2f high ; Ivs. lance-linear, about 3' long, roughish, on smooth, striate sheaths ; 

 panicle oblong, contracted, nodding, yellowiah-green ; spikeleis about S" long, 2 — 3- 

 flowered, middle flower abortive, upper one pedicellate, its lower palea ending in 

 2 setous teeth, and awned below the tip, lower one mostly awnlesa. — U Wet 

 meadows, Mass., N. T. to Fla. May — July. (Avena, Mx. Aira pallens, 

 Muhl.) 



2 T. m611e Kunth. Mimiiehj and softly puierulenHhromghout; calm Ifhigh-lva. 

 narrow, 2 to 4' long; pan. contracted and ^ike-like, 2' long; awn at length do- 

 flexed, longer than the beardless flowers. — Mts. and rocks, N. H. to Mich, and 

 Can. (Avena, Mx.) Scarcely differs from the foregoing, which is also sometimes 

 downy. 



3 T. purpurdscens Torr. Culpi leafy, 2f high; tos. narrow-linear, keeled, 

 4 — 6' long, and with the sheaths smooth ; panicle very simple, almost a raceme, 

 few-flowered, 4 — 6' long ; glumes 3 to 5-flowered, very unequal, entire ; spikeleis 6 

 to 8" long, lanceolate, terete, often purple, smooth ; lower palea T-veined, cleft 

 into 2 bristly points at the apex; awn geniculate. — 2f Mountain bogs, N. Eng. 

 to Wis. and Can. June. 



30. BRO'MUS, L. Brome Grass. (Gr. Ppcofxa, food ; the name 

 was anciently applied to Oats.) Spikelets 5 to oo -flowered ; glumes un- 

 equal, membranous, veined ; lower pale 5 to 9-veined, convex or cari- 

 nate on the back, awned from below the mostly bifid tip ; upper pale 

 ciliate on the 2 keels, often bifid ; caryopsis linear, adherent to the 

 tif)per pale. — Coarse grasses with flat Ivs. and large, paniculate, noddirig 

 spikelets. 



S Glumes narrow, the lower l-veined, upper 8-YeIne(l. Pale keeled Nos. 6, 5 



§ Glumes veiny, the lower 3 to 5, upper 5 to 7-veined (a). 



a Lower pale compressed-carinate, the awn scarcely any Ko. 4 



a Lower pale rounded on the back, the awn conspicuous Nos. S — 1 



1 B. secalinus L. Smooth Cheat oe Chess. Culm smooth, 2 to 4f high ; Ivs. 

 lance-hnear, 6 to 12' long, rough and some hairy above, on smoothish sheaths; 

 pan. spreading in fruit, branches subsimple, with few nodding spikelets ; spkl. 

 ovate, turgid, smooth, 1 to 10-flowered; fls. soon diverging and rather distinct, 

 oblong, longer than the short, flexuous airo. — CD A handsome but worthless grass, 

 in fields of wheat and other grains, and in waste grounds. Jn., Jl. § Bur. 



2 B. mollis L. Downy Chess. Culm slender, some downy, 12 to 18'to2f; 

 Ivs. flat, hairy both sides, lance-haear, on sheaths clothed with deflexed hairs ; 

 pan. erect, contracted in fruit ; spikelets ovate, compressed, about 6-ftowered, downy 

 all over ; fls. oblong, closely imbricated, not longer than their straight awn. — (D ® 

 Wheat fields and waste grounds, rare. Lower pale J longer than the upper. 

 Jn. § Eur. Varies in pubescence. (B. racemosus L. p. arvensis, Ed. 2.) 



3 B. Kdlmii Gray. Culm slender, 18' to Sf; Ivs. and sheaths more or less hairy, 

 sometimes excessively so ; pan. simple, small, 3 to 4' long ; spkl drooping, closely 

 7 to 1 2-flowered, densely silky all over ; lower glume 3-veined, upper 5 ; lower 

 pale much longer than the upper, 5 to "T-veined, the awn -J of its length. — y Dry 

 hilly woods, U. S. and Can. Jn., Jl. (B. purgans Torr. nee L. fide Prof. 

 Gray) 



4 B. unioloides Thunb. & Kth. Rescue Grass. Culm 18' to 3f, glabrous; 



