CHAPTER VIII 



a 



THE FLOWER : FERTILISATION AND DEVELOPMENT OF THE GRAIN 



IMMEDIATELY within the flowering glumes are two minute antero-lateral 



scales, the lodicules, which probably represent a small divided glume, 



although they are sometimes regarded as rudimentary perianth leaves. 



They are thin and colourless, 

 about i mm. long, -7- -8 mm. 

 wide near the top, and -4- -5 

 mm. at the base, with long 

 hairs on the upper margin ; at 

 the flowering period they swell 

 enormously,' becoming for a 

 short time more or less spheri- 

 cal, resembling pellucid drops, 

 pushing apart the glumes and 

 exposing the stamens and 

 stigmas of the flower ; later, 

 they collapse and the glumes 

 close again. 



The perfect flower is hypo- 

 gynous and simple in struc- 

 ture, consisting of a whorl of 

 three stamens and a single 

 carpel (Fig. 84). 



One or more of the upper 

 flowers of a spikelet are im- 

 perfect, the ovary being rudi- 

 mentary and the anthers 

 without pollen grains ; fre- 

 quently the terminal flower 



is missing altogether, and the flowering glumes and pales, though present, 



are poorly developed. 



In many instances the entire spikelet is sterile ; especially is this the 



case in the lowest three or four of an ear. Occasionally one or two of 



the apical spikelets are abortive also. 



FIG. 84. Flower before anthesis. a, Anther 

 style ; /, lodicule. Dehiscing anther below 



