202 POACE^. 



Panicle sleuder. 8-15 cm. long; first glume 7 mm. long, second 6 

 mm. long; awus of floret 1.5 mm. long. 



Xortheast Florida, Curtiss 3429; Mississippi, Tracy 133; New 

 Jersey, Beal 38. 



15. A. oligantha Michx. Fl. Bor. Am. 1:41 (1803). A. Ad- 

 scensionis AValt. Fl. Car. 74 (1788), not L. Cluetaria oligantha 

 Beauv. Agrost. 30 (1812). 



Apparently annual ; culms witli tumid nodes, sparingly branched. 

 20-50 cm. high. Sheaths about as long as the internodes some of 

 which are naked, as the branches crowd the sheaths; ligule very 

 short, with a few long hairs above it. Panicle loose, few-flowered, 

 racemose, 10-15 cm. long. Empty glumes nearly equal, 2 cm. 

 long, first 3-5-nerved, with a very short awn, second 1-nerved, Avith 

 an awn 1 cm. long; floret 15 mm. long; awns diverging when ma- 

 ture, the central one 4 cm. long, the lateral ones a little shorter. 



District of Columbia, McCartliy; Massachusetts, C. E. Faxon 

 8; Mississippi, Tracy. 



Virginia, Illinois, Arkansas and southward. 



Var. nervata. Empty glumes shorter than the floret, first 7- 

 nerved, the divergent awns 1-2 cm. long. 



Oregon (Grant's Pass), Howell. 



16. A. Palmeri Vasey, Bull. Torr. Club, 10:42 (1883). 

 Perennial; 15-30 cm. high. Leaf-blades involute, setaceous, 



the lower 2-5 cm. long, some of those above 10-12 cm. long. 

 Spikelets 80-100 to a culm in some cases, in terminal and lateral 

 panicles, 12 cm. long, 6 cm. wide; branches scabrous. Some of the- 

 lower spikes often more or less reduced or abortive. Spikelets 

 mostly in pairs; first glume linear-lanceolate, 1-nerved. about 7 

 mm. long, 1 mm. wide; second membranous, narrowly linear, 8-9 

 mm. long; floret cylindrical, 4 mm. long, the awns nearly equal,, 

 erect or diverging, 10 mm. long. 



Colorado, Jones 4138; West Texas, Havard; Nebraska,. 

 Duffcy. 



Nebraska, Arizona and Texas. 



17. A. virgata Trin. Spreng. Neue Entdeck. 2:60 ( ). 

 Culms erect, slender, naked above, sparingly branching below„ 



