HOW TO KNOW THE GRASSES 



22a. Each joint bearing 2 spikelets, usually one sessile and perfect and 

 one pedicellate and staminate or sterile; glumes thick, the fertile 



lemma very thin and delicate 



TRIBE XII, ANDROPOGONEAE, page 176 



22b. Each joint bearing 3 spikelets, the lateral two often sterile and 



reduced in size; lemmas not thin and delicate 



TRIBE III, HORDEAE, page 85 



23a. Inflorescence a panicle, sometimes dense or contracted; each 



25 



spikelet on a pedicel, 



23b. Inflorescence of one or more spikes, the spikelets 

 sessile 24 



24a. Spike single, terminal, with the spikelets borne in rows 



on opposite sides of the rachis. Fig. 36 



TRIBE III, HORDEAE, page 85 



Figure 36 



24b. Spikes 1 — many, the spikelets arranged in two rows on the 



lower side of the rachis of each spike. Fig. 35 



TRIBE VII, CHLORIDEAE, page 131 



25a. Spikelets consisting of two (rarely one) glumes and 

 a single perfect floret, no staminate or rudimentary 



ones with it. Fig. 37 



TRIBE V, AGROSTIDEAE, page 102 



Figure 37 



25b. Spikelets with a perfect terminal floret and one or two staminate 

 or rudimentary ones, often reduced to little scales, below it 26 



21 



