A GUIDE AND KEY TO AQUATIC PLANTS 



77 



3. Plants with two kinds of spikelets; that is, pistils and 4. 



stamens borne in different spikelets. 

 3. Plants with all spikelets alike; stamens and pistils in 6. 

 same spikelets. 



4. Inflorescences not expanded; the lower pistil- 16. Tripsacum,p. 84. 

 late portion breaking up into bony, bead- 

 like joints (fig. 3). 



4. Inflorescence expanded 5. 



5. Pistillate spikelets borne above staminate in inflores- 4. Zizania, p. 81. 



cence; leaves not cutting (fig. 4). 

 5. PistuUate and staminate spikelets intermixed; leaves 6. Zizaniopsis, p. 82. 

 with scabrous, cutting margins (fig. 5). 



Figure 3 



x'A 

 Figure 4. 



Figure 5, 



