206 POACE.E. 



mostly in jmirs, spreadiDg or even reflesed witli a spongy callus in 

 the axils, the largest few- flowered, 5-G cm. long, brauchiug about 

 1 cm. from the base, emj^ty glumes nearly equal, scabrous on the 

 keels, 1-nerved, 8-10 mm. long; floral glume spotted, smooth, the 

 apex scabrous, 7-8 mm. long, lateral awns 10-15 mm. long, the 

 middle one a very little longer. 



Western Texas, Havard; Arizona, Touincy T85. 



23. A. palustris Vasey, Cat. Gram. U. S. 35 (1885). A. viryata 

 var. 7Jrt/^^s-//w■6• Chapm. Fl. S. States 555 (18G0). 



Culms branching near the base, 60-150 cm. high. Sheaths close; 

 ligule very short; blades flat or involute, rigid, 10-20 cm. long, 3 

 mm. wide. Panicle loose, interru})ted, 30-70 cm. long. Empty 

 glumes compressed, keeled, nearly equal or the second longer, 1- 

 nerved, 7-9 mm. long; floret 5-6 mm. long, the lateral awns 12-15 

 mm. long, the central a little longer, and when dry spreading more 

 than the others. 



Mississippi, Tracy; Xortheast Florida, Ctirtiss 3-425. 



Pine-barrens. West Florida and South Alabama, 



24. A. setifolia II. B. K. Nov. Gen. et Sp. 1:122 (1815). 

 Cluetaria setifolia R. & S. Syst. 2: 396 (1817). 



A tufted branching perennial grass, 30-90 cm. high. Sheaths 

 shorter than the internodes; lower leaf -blades numerous, narrow, 

 involute, 15-20 cm. long, those of the culm 3 to 4 in number. 

 Panicle l)ut little exserted, often included at the base, ratlier thin 

 and spikelike, 12-15 cm. long, branches compound, 14.5 mm. 

 from each other, 3-4 cm. long; empty glumes scabrous on the keel, 

 abruptly pointed when spread, 1-nerved, first 4-0 mm. long, second 

 6-8 mm. long; floral glume scabrous, linear-lanceolate, 5-6 mm. 

 long, the awns diverging, nearly equal, or the middle one slightly 

 sliorter or longer, 8-15 mm. long. 



Mexico, Palmer 501, 769. 



Also found in Brazil. 



25. A. fasciculata (K. & S.) Torr. Ann. Lye. N. Y. 1 : 154 

 (1824). Cimfaria fasciculata R. & S. Syst. 2 : Mant. 578 (1817). 

 A. pttrpiirea'S nit. Trans. Am. Philos. Soc. (II.) 5:145 (1837). 



