10 BULLETIN 1157, U. S. DEPARTMENT OF AGRICULTURE. 
the weight of ear. The ear showed greater variability in weight in 
the single-ear type, whereas the number of ears per plant was more 
variable in the prolific type. 
In Table 8 the experiments have been classified to show in per- 
centage form the relation of increase in the weight of ear to increase 
in the number of ears per plant. The percentages are based on the 
oerformance of each type at the closest spacing. In general, the 
experimental evidence supports the assumptions made earlier in this 
bulletin as to the reaction of the two types of corn to a better environ- 
ment. 
CONCLUSIONS. 
In these experiments the prolific type has been more productive 
than the single-ear type. 
The prolific type has been more efficient than the single-ear type 
in increasing the yield per plant and in increasing the number of ears 
per plant. In increasing the weight of ear the single-ear type has 
been more efficient. Increasing the number of ears per plant has 
been more effective in increasing the yield per plant than has in- 
creasing the weight of ear. 
The experiments indicate that in sections to which both types are 
adapted the prolific would be the more productive type under the 
conditions of general field culture because of its better adjustment 
to varying conditions. 
