74 NEW YORK STATE MUSEUM 



conditions oviposition by the elm leaf beetle begins the latter 

 part of May and continues throughout June, being at its height 

 in the middle of the month. The month of June was therefore 

 divided into three ten-day periods and the maximum, minimum 

 and effective temperatures tabulated for the past decade, namely, 

 from 1905 to 19 14. In one series of tabulations 43 F. was taken 

 as the biological zero, and in the other 55 These tabulations are 

 given below. 



