464 



Journal of Agricultural Research 



Vol. XIX, No. 9 



flowering, the diameters of the normal kernels are larger than those 

 from clipped spikes, and they then continue larger for the remainder of 

 the period of development. In Minnesota, there is little difference 

 between the kernels of the two classes of spikes until near maturity. As 

 maturation approaches, the normal kernels are found to be uniformly 

 greater in diameter than are those from the clipped spikes. 



The graph of the wet weight is much more uniform at Aberdeen than 

 at St. Paul. As in Minnesota, there is no difference between the clipped 

 and normal spikes in the first few days. The period of equality is shorter 



8 9 /o///^/3/4/5/6/7/8/92o^/^^^5^4^s^6^7^B29J03// 23 



Fig. 8. — Graph showing wet weight of kernels of Hannchen barley from normal and clipped spikes. 



at Aberdeen, however. After July 15 the average wet weight of the 

 kernels from clipped spikes here never equals the wet weight of the 

 kernels from normal spikes. 



The wet weight -includes a variable amount of water, which increases 

 during the first half of the growing period and decreases during the 

 second half. I^or this reason the curv^e of the wet weight differs greatly 

 from the cur\^e of the dry weight. The dry weights are shown in figure 9. 

 In Minnesota, the trend of increase in dry weight was quite uniform, as 

 was shown in figure 3. In Idaho, the graph of the dry weight is almost 

 a straight line. It would seem that in both the normal and clipped 



