312 POACE.E. 



a second, sessile or on short stiil stniiglit or curved pedicels, linear, 

 about 3 mm. long; the three glumes softly scabrid with small warts; 

 first empty glume lanceolate, 1-2-3-nerved, often toothed, '^.5 mm. 

 long, second ovate-lanceolate or lanceolate, 3-5-nerved, often 

 toothed, 2-'^. 5 mm. long; lloral glume very thin below, broadly 

 oval, obtuse or truncate, often with very short teeth, '^'-o-nerved, 3 

 mm. long; palea oval, hyaline, 2-nerved, 2 mm. long. 



Mexico (Chihuahua), Pritujie 14'23. 



63. (131). POLYPOGON Desf. Fl. Atl. 1:0(3 (1798). Stwtia 

 Savi, Mem. Soc. Ital. 8c. (VIII.) 2:4:9 (1T9S). liusjiaiUa Mem. 

 See. Ital. Mod. 8: (2) 479 (1798). Presl. Keliq. llt«nk. 1:238, /. 

 40 (1830). ^'oimlti'orsk-jia Presl, IJel. Ihvnk. 1:238 (1830). 



Spikelets l-Uowered in a dense si)ikelike or slightly interrupted 

 and spreading panicle, pedicels articulate with a tuft of short hairs 

 above the articulation; empty glumes subequal with a terminal 

 straight awn, iloral glume smaller, thinner, usualh' hyaline, entire 

 or notched, with an awn in the notch or on the back, either twisted 

 and bent at the base, or small and straight or reduced to a minute 

 point. Palea smaller. Stamens 1-3. Styles short, distinct. CJrain 

 enclosed but not adherent. 



These grasses arc mostly annuals with decumbent bases. The 

 panicle is terminal. There are ten species widely distributed over 

 the globe. Bentham says: "The ger end structure is almost pre- 

 cisely that of Ganiotia in tribe Trisu ,:iUW, from which indeed 

 PoJjipogon only differs in the inflorescence being dense and spikelike, 

 not loosely paniculate." 



A. Awns nearly concealing the spikelets 1, 3 



B. Awns not concealing the spikelets (a) 



a. Empty glumes linear-lanceolate 3 



a. Empty glumes obtuse when spread open 4 



1. P. MONSPKLIEXSIS (L.) Dcsf. 1. C. AXXUAL BeARD-GRASS. 



Alnpecurus nioihspeh'eiisis L. Sp. PI. 89 (1753). 



An erect or geniculate annual, 30-3G cm. high. Sheaths nearly 

 as long as the internodes, the upper slightly inflated; ligule 4-6 

 mm. long; blades flat, scabrid. Spikelike panicle mostly exserted, 

 oval or cylindrical, dense, showing branches more or less, often of a 



