PANICE^. 151 



A. Leaf -blades plicate , 15 



B. Bristles with fiue teeth pointing downwards 1 



C. Bristles with fine teeth pointing upwards (a) 



a. Plants 3-6 meters high 2 



a. Plants 25-60 cm. high. Sheaths compressed. . 3, 4, 5, 6 

 a. Plants nsually 8-20 cm. high (No. 7 often taller). Sheaths 



compressed little if any (b) 



b. Exotic, cultivated, 20-40 cm. or more high. ... 7 



b. Native in Florida and Texas 8 



a. Plants usually 30-60 cm. high. Sheaths compressed little if 



any (c) 



c. Spikes tawny yellow when mature 9 



0. Spikes green or reddish brown when mature. . . .(d) 



d. Fertile floret strongly wrinkled transversely, as in C. 



glcmca 10, 11 



d. Fertile floret not wrinkled transversely, or only as seen 



under a lens (e) 



e. Spikes dense 12 



e. Spikes interrupted (i) 



i. Spikelets 3 mm. long 13 



i. Spikelets 2 mm. long, bristles single. ... 14 



1. C. verticillata (L.) Porter, Bull. Torr. Club, 20:196 (1893). 



Fanicum verticillatum L. Sp. PI. Ed. 2, 82 (1762). Pennise- 

 tum verticillatum R. Br. Prod. 1 : 195 (1810). Setaria verticillata 

 Beauv. Agrost. 51 (1812). 



Culms erect or ascending, branching and cylindrical below, 

 30-60 cm. high. Sheaths smooth, loose; Hgule ciliate; blades flat, 

 rough, twisted (?), broad at the base, of large specimens, 15 cm., 

 long, 12-15 mm. wide. Spikelike panicle green, often rather 

 loose and interrupted at the base, the spikelets densely clustered, 

 each pedicel bearing 1-2 bristles twice as long as themselves 

 with the asperities directed downwards. Spikelets oval, about 2 

 mm. long, first glume one-lialf the length of the spikelet, 1-nerved, 

 second nearly as long as the third, broad, 7-nerved, tlie latter 5-7- 

 nerved; fertile floret smooth, tlie minute transverse wrinkles 

 scarcely visible, even under a lens. 



