FESTltE.E. 443 



a. Puiiicli' spikolike, llonil glunies tt'rmiimtliig iu 9-2:} 

 pluiiuKSK uwns 07 



a. Puiiick; lax, lloral glumes tormiiiatiiig in D-U irregu- 

 lar lol)o.s OH 



a. Panicle raceinoae, floral glumes terminating in '.]-'> 

 rigid lobes 10.'} 



a. Panicle subspicate, lloral glumes terminating in 5 deli- 

 cate awns 104 



a. Spikelets in threes ou a jointed racliis, lloral glumes 

 deeply 4-cleft with awns between the lobes. ... 00 



a. Plant dia'cious, iloral glumes of fertile florets .'3-clet't. 100 

 B. Floral glumes entire or '^'-toothed to 2-clei't, awnless or 



with 1 awn (b) 



b. Tall reedlike grasses (c) 



c. Floral glumes clothed with long hairs 10") 



c. IJachilla (alone) clothed with long hairs. . , , 10(J 

 b. IS'ot reedlike, floral glumes naked or containing hairs 



shorter than the glumes (d) 



d. Stigmas with short hairs on all sides (e) 



e. Spikelets dicecious, solitary, termiiud, enclosed 



by terminal bracts 101 



e. Spikelets in twos and threes, terminating in 

 leafy branches lOv' 



e. Spikelets in an ovoid or cylindrical panicle, low- 

 est s[)ikelets with bracts at the base 104 



d. Stignuis ])lumose (f) 



f. Spikelets of two forms, the fertile l-3-llowered; 



the sterile with iiwned glumes (g) 



g. Fertile spikelets 1-flowered V^'o 



g. Fertile spikelets 2-3-flo\vered 124 



f. Spikelets all alike (h) 



h. Floral glumes 2-3-toothed, lateral nerves 



and callus usually hairy (i) 



i. Spikelets 3- to many-flowered. . . . lOT 



i. Si)ikelots 3-5-flowered 108 



h. Floral glumes of some other structure. . . (j) 



IV 



