PERIODICITY IN THE PRODUCTION OF MALES. 1 97 



producers; in starved families, on the other hand, the greatest 

 numbers of male producers were not in the largest families, but 

 in those of medium size. On the statistical evidence as a whole, 

 the influence of quantity of nutrition upon male production is 

 held to be "not proven." When qualitative differences in 

 nutrition affect male production, the interval between periods of 

 many males probably remains unchanged. 



BIBLIOGRAPHY. 

 Mitchell, C. W. 



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