A<iH(^STIDE.K. 220 



a. Hairs of floret not dense nor conspicuous (e) 



c. Awn plumose 5 



c. Awn stout, persistent, scarcely as long as the empty 



glumes, curved in one i)Iane, spikelets o mm. long, 



panicle 2-5 cm. long (» 



e. Awn deciduous, not over 4 mm. long, spikelets 4 



mm. long, panicle 4-8 cm. long 7 



e. Awn 10-12 mm. long, spikelets 4 mm. long, panicle 



narrow, 5-8 cm. long . 8 



c. Awn i»-lG mm. long, spikelets 4-5 mm. long, panicle 



T-13 cm. long 9 



c. Awn 10-15 cm. long, spikelets 4 mm. long, panicle 



8-12 em. long 10 



c. Panicle 8-lG cm. long, awn deciduous, 5-10 mm. 



long II 



c. Leaf-blades flat or involute, ligule not ciliate. . .(d) 



d. Panicle 15-20 cm. long, awn 20 mm. long. . .12 



d. Panicle 10-13 cm. long, awn 1.5-2 mm. long. 13 



1. 0. melanocarpa Muhl. Gram. 79(1811). Milium mcemosutn 

 Sm. Rees, Cyc. 23 :n. 15 (1810?). Piptalherum nigrum Torr. 

 Fl. U. S. 1:79 (1824). Vrachne racemom Trin. Unifl. 1:174 

 (1824). 



Culms erect, slightly rough, leafy at the top. 60-100 cm. high. 

 Sheaths scabrous, about as long as the internodcs; ligule short and 

 bearded; blades flat, lanceolate, not quite smooth, tapering towards 

 each end, 25-30 cm. long, 10-15 mm. wide. Panicle simple, nar- 

 row, scarcely cxserted, 12-20 cm. long. Si)ikelcts elliptical, acute, 

 about 7 mm. long, empty glumes sube(|ual, reticulate-veined, 7- 

 nerved; floret with a few appressed hairs, blackish, the awn 1.5-2 

 cm. long. 



Vermont, Prinyle ; Delaware, Canhy ; Ontario. Fowler; Xew 

 York, Be(d 42 ; Michigan, Clark, 703; Iowa, Hitchcock ; Minne- 

 sota, IlobJnger 20''. 



NeAV England, Delaware, Pennsylvania to Wisconsin. 



2. 0. asperifolia [Rich, in] Michx. Fl. Bor. Am. 1:51 (1803). 

 Vrachne ((sperifolia Trin. Unifl. 174 (1828). 



