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THE AMERICAN NATURALIST [Vol. XLIX 



For the 5x4 grouping of the 500 wheat plot of Mercer 

 and Hall I find the values given in Tables V-VI. 



For the regression of the second on the first plot the 

 equations are : 



For grain, g, g^= 3.214 + .186 # T . 



Figs. 1 and 2 exhibit the usual irregularities of sam- 

 pling in the means, but show no certain departure from 

 linearity. 



