No. 21. 



ANDROPOGON WRIGHTII Hackel. 



Rootstock thick. Roots very strong. 



Culms csespitose, 2 to 3 feet high, unbranclied, smooth, slightly hairy at the 

 nodes. 



Leaves. Sheaths smooth, striate, shorter than the internodes ; ligules 1 line 

 long, obtuse, smooth; blades 5 to 12 inches long, 2 to 3 lines wide, light green, 

 smooth, the margins scabrous. 



Panicle 2 to 3 inches long, consisting of 5 to 7 clustered or approximate spike- 

 like branches 1| to 2 inches long, shortly pedicellate, erect, and densely flowered; 

 rachis flattened, hairy, ciliate. 



Spikelets about 3 lines long, in pairs, one female, one male. Female spikelet 

 sessile, lance-oblong, hairy at the base, sparsely hairy on the back below ; first 

 glume thick, 7-nerved above ; second nearly equal to the first, 3-nerved ; third and 

 fourth hyaline, fourth with an awn A inch long. Male spikelet on a ciliate pedicel 

 of half its length, about 3 lines long; first glume 9- to 11-nerve.d at the base, ciliate 

 on the margins above; second more acute, 3-nerved, ciliate; third hyaline, nearly 

 equaling the second; fourth very minute or wanting. 



Plate XXI ; a, pair of spikelets ; b, female spikelet spread open to show the 

 parts ; c, male spikelet opened. 



This resembles the preceding species, but is smaller and with fewer spikes. It 

 is rare, at least north of the boundary. 



