HOW TO KNOW THE GRASSES 



18b. Glumes thicker and stiifer than the delicate 

 fertile lemma and palea; both glumes as long 

 as the spikelet; spikelets paired, in racemes; 

 one spikelet of each pair sessile or on a short 

 pedicel, the other on a longer pedicel, some- 

 times rudimentary. Fig. 34 



....TRIBE XII. ANDROPOGONEAE, page 176 



Figure 34 



19a. Spikelets borne in two rows along the lower side of 

 the rachis of numerous spikes, which are borne in a 

 raceme along a common rachis; spikes dropping from 



the rachis whole. Fig. 35 



TRIBE VII, CHLORIDEAE, page 131 



19b. Spikelets not borne in rows along the lower sides of 

 the 1 — many spikes; spikes remaining whole or break- 

 ing up into groups of spikelets or single spikelets. .20 



X 





^ 



^ 



Figure 35 



20a. Rachis breaking up into joints at maturity, each joint bearing 2 

 — 3 spikelets 22 



20b. Rachis remaining intact, the groups of spikelets falling from it. .21 



21a. Spikelets falling with a ring of long hairs attached 



see Fig. 284. (genus Pennisetum) 



21b. Spikelets without a ring of hairs attached 



TRIBE VI, ZOYSIEAE, page 129 



20 



