94 FIRST BOOK OF GRASSES 



three of the spikelets, and sometimes it is sup- 

 pressed. 



The staminate inflorescence (Fig. 82, E) resembles 

 the spikes of grama-grass (Fig. 51, E) but the spike- 

 lets (Fig. 82, F) are awnless, and the second floret is 

 well developed and contains a staminate flower. 



SUMMARY 



In the case of greatly modified structures the 

 different organs are to be interpreted by their relative 

 position and by their analogy to corresponding 

 organs in related grasses. 



BEVIEW 



Collect the inflorescence of Tripsacum if available, disjoint 

 it and dissect the spikelets. 



Examine a very young ear of corn and note that the spikelets 

 are always in pairs (consequently an ear of com always has an 

 even number of rows). Distinguish the glumes and lemmas. 

 Examine the staminate spikelets. 



If available, collect buffalo-grass and dissect the staminate 

 and pistillate inflorescence, preparing the latter by boiling it a 

 few moments in water to which a few drops of glycerine have 

 been added. When no glume but the large thickened one is 

 found in the pistillate spikelet of buffalo-grass, how do you know 

 which glume that is? 



