PANICE.E. 105 



billet), P. colonum {Sliama MiUet), form important articles of 

 food for man and domestic animals. 



A. DiGiTARiA (Heist, as a genus). Spikelets croicded 3-3 to- 

 gether, mostUj in jxiirs. along the onter or lower side of siinpte 

 clustered 1-sided spikes on short pedicels of loiequal length ; 

 outer glume very small or obsolete ; root mostly annual. Some 

 species are very closely allied to Paspalnm. 



a. Spikes erect, rachis less than 0.5 mm. wide 1 



a. Spikes spreading, rachis less than 0.5 mm. wide. . . 2, 3 



a. Spikes sjd reading, rachis abont 1 mm. wide (b) 



b. Spikelets oblong, acute, about o mm. long. ... 4 



b. Spikelets ellijitical or ovoid (c) 



c. Leaves smooth, 3-4 mm. wide 5 



c. Leaves hairy, 5-7 mm. wide 6 



B. Trichachxe (Xees as a genus). Spikelets panicded, silky- 

 hairy, narrow., slender, clustered or rarely in pairs along the 

 rachis of the 2-few long erect branches ; fruiting glume not 

 much hardeiied. Species few 7, 8, 9 



C Brachiaria (Griseb. as a genus). Spikelets awnless, single or 

 in twos and threes, 2-Jf.-seriate along simple spikes borne on the 

 axis. Nearly allied to Paspalnm, differing from that genus in 

 having a small first or lower glume. Shading off with some of 

 the sparingly-flowered species into Eupanicum, comprising 

 many species. 



a. Spikelets single and in two rows (b) 



b. Spikes 4-6 cm. long ' . . . . 10, 11 



b. Spikes 1-3 cm. long ..(c) 



c. Spikes 4-8 approximate 12 



c. Spikes 8-12 on about 10 cm. of the axis. . . , 13 

 c. Spikes 10-15 on 20-30 cm. of the axis .... 14 



a. Spikelets in twos or threes (b) 



b. Spikes appressed. the lowest often not overlapping . (c) 



c. Plant tall, erect. 15 



c. Plant creeping 16 



b. Spikes spreading, imbricate (c) 



c. Peduncles about 0.5 mm. diam 17 



