610 POACE^. 



c. Branches of panicle flexuose ; spikelets smooth, 

 flat, oval, floral glume broadly oval, awns 5-10 



mm. long 14 



c. Branches of panicle short, ascending ; spikelets 

 pubescent, flat, oval, floral glume broadly oval, 



awn 6-8 mm. long 15 



c. Plant otherwise than those above (d) 



d. First glume 1- (rarely 3-) nerved, second 



3-nerved (e) 



e. Joint of rachilla 2 mm. long or less, spike- 

 lets 7-12-flowered 16 



e. Joint of rachilla 2 mm. long, sjnkelets 



3-6-flowered 17 



e. Joint of rachilla more than 2 mm. long. . ( f ) 

 f. Blades involute, 2-3 mm. wide. . . 18 



f. Blades flat, 2-3 mm. wide 10 



f. Blades flat, 4 or more mm. wide. . . (g) 



g. Awn 2-3 mm. long 20 



g. Awn 4 or more mm. long. . . . (h) 

 h. Longest rays 8-10 cm. long, an 



exotic annual 21 



h. Longest rays 3-5 cm. long, a 



native perennial 22 



d. First glume 3-nerved (rarely 1-nerved), sec- 

 ond glume 3-nerved 23 



d. First glume 3-nerved, second 5-7-nerved. . (i) 



i. Spikelets scabrid 24 



i. Spikelets densely silky hairy 25 



d. First glume 3-nerved (rarely 5-nerved), sec- 

 ond glume 7-nerved, spikelets firm, flat, 

 floral glume turgid, broadly oval, apex obtuse, 



exotics 26, 27, 28 



1. B. RUBENS L. Cent. 1:5 (1755). Festuca ruhens Pars. Syn. 

 1: 94 (1805). B. canescens Viv. Fl. Lyb. Spec. 5 (1824). 



A soft densely tufted slender annual, 20-40 cm. high. Leaves 

 3 in number, ligule lacerate, 1.5-2 mm. long ; blades jmle 



