134 
Journal of Agricultural Research 
Vol. XI, No. 4 
differences in means 
[Fig. 17 to 20] 
In 6 of the 10 years of this experiment we find that the mean lengths 
of the erect ears exceed those of the dec linin g ears. In 7 of the 10 years, 
Fig. 17.—Graphs showing the mean length of the ears of the erect- and declining-ear strains of Indian 
com. 
the means of weights of erect ears exceed those of declining ears. In 
mean number of rows of kernels on ears, there is no significant difference 
dian com. 
between erect and declining ears. Taken as a whole it seems that no 
differences in means are large enough to persist well from season to 
season. The fact that the erect ears are on the whole, at least as heavy 
