130 



THE SMALL GRAINS 



adjoining rows of side spikelets of two opposite sets lean 

 toward each other, those of one row coming alternately 

 over and under those of the other in such a way as to 

 produce the illusion of one row of spikelets. In certain 

 Abyssinian forms the illusion is most complete, only four 

 very distinct rows appearing to be present. All grada- 

 tions of length of internode exist, so that this distinction 

 between the groups is not a good one. 



Common barley is a very old group, and t'he many 

 varieties are widely distributed. It 

 is at present the chief source of 

 brewing varieties in North America, 

 though two-row varieties are extend- 

 ing their area. It predominates in 

 Russia, Syria, and Turkestan and in 

 South America. The only very 

 hardy winter barleys are in this 

 group. Such varieties occur particu- 

 larly in southern Russia and western 

 Asia. 



123. Groups of common barley. - 

 The most important group is that of 

 the pale yellow barleys with straight 

 beards. It includes winter varieties 

 in southern latitudes. Such varieties 

 differ none in form from the spring 

 varieties, but if sown in the spring, 

 produce few or no culms that season. 

 Some representatives of the group 

 are very sensitive to wet cold. 

 Curious forms occur having a trifurcate appendage in 

 place of the awn, one of the segments of which is hood- 

 shaped, these forms being known as hooded barleys. 



FIG. 41. Kernels of 

 common or nodding 

 six-row barley. 



