CIILOKIDE.E. 



411 



■empty, beuriug an awn; pulea narrow, 2-keeled. Styles distinct. 

 Oraiu linear, subterete, enclosed by a firm glume, but not adherent. 

 Tall grasses witli short firm or long and flaccid leaves. Spikes 

 numerous, slender or filiform, at first erect, finally spreading, 

 scattered, or those below in whorls. 



Species 5 or G, belonging to America or the Old World. 



A genus nearly allied to Chloris. Our species are perennial 

 from short rootstocks, with short firm blades, 1-nerved empty 

 glumes, the floret bearing short hairs at the base. 



Gymnopogon difl:ers from Tricldoris in not having the spikelets 

 closely crowded, altliough sessile in two unilateral rows, the spikes 

 scattered or verticillate. 



1. G. ambiguus (Michx.) B. S. P. Prel. Cat. N. Y. 69 (1888). 

 Andropogon ar,ibiguus Michx. Fl. Bor. Am. 1 : 58 (1803). G. race- 

 mosus Beauv. Agrost. 164 (1812). G. scoparius Trin. Unifl. 237 

 (1824). 



Culms wiry, leafy, clustered, 30 cm. high. 

 Ligule a fringe of hairs; blades flat, lance- 

 olate, 3-8 cm. long. Spikes 15-30 in number, 

 7-17 cm. long, each bearing 7-20 spikelets, 

 remote at the base. Empty glumes 1-nerved, 

 first 5 mm. long, second 6 mm. long, includ- 

 ing a short awn; floral glume cylindrical, 

 involute, 4 mm. long, with an awn as long; 

 empty terminal glume raised on a rachis over 

 2 mm. long, bearing an awn of equal length. 

 Grain narrowly oblong, 2 mm. long. 



Maryland, Behh; Florida, Curtiss 3441. 



Sandy pine-barrens, Xew Jersey to Texas. 



2. G. brevifolius Trin. Unifl. 238 (1824). 

 Agrost. Bras. 430 (1829). 



Culms slender, wiry, leafy, 30-CO cm. high. Ligule obsolete, 

 destitute of hairs; blades 2-5 cm. long. Spikes 15-20, very slender, 

 8-20 cm. long, containing 8-30 spikelets, sometimes borne on the 

 upper half or two-thirds. Empty glumes pointed, slightly unequal, 

 3-3.5 mm. long; floral glume 2.5 mm. long, with an awn 1 mm. 



Fig. 74. — Oyvinopogon 

 ambiguus. Spikelet. 

 (Riclianisoii.) 



G. fadigialns Xees, 



