THE EUROPEAN CORN BORER AND ITS CONTROL. 35 



Second Generation. 



Incubation Period. 



The eggs are deposited in masses on various parts of the food plant 



selected for oviposition. They hatch, on an average, in 6 days, with a 



maximum of 8 and a minimum of 4 days (see Table VIII). Duration of 



the incubation period depends upon temperature conditions. 



Table VIII. — Duration of Incubation Period — Second Generation. 



Observation Number. 



200, 

 201, 

 202, 

 203, 

 204, 

 205, 

 206, 

 207, 

 208, 

 209, 

 210, 

 211, 

 212, 

 213, 

 214, 

 215, 

 216, 

 217, 

 218, 

 219, 

 220, 

 221, 

 222, 

 223, 

 224, 

 225, 

 226, 

 227, 

 228, 



Number of 

 Eggs. 



87 

 71 

 103 

 103 

 79 

 67 

 89 

 78 

 112 

 101 

 151 

 128 

 77 

 64 

 223 

 75 

 205 



Deposi- Hatch- 

 tion, 1918. ing, 1918. 



July 

 July 

 July 

 July 

 July 

 July 

 July 

 July 

 July 

 July 

 July 

 July 

 Aug. 

 Aug. 

 Aug. 

 Aug. 

 Aug. 

 Aug. 

 Aug. 

 Aug. 

 Aug. 

 Aug. 

 Aug. 

 Aug. 

 Aug. 

 AuE. 

 Aug. 

 Aug. 

 Aug. 



Aug. 2 

 Aug. 2 

 Aug. 3 

 Aug. 3 

 Aug. 5 

 Aug. 6 

 Aug. 6 

 Aug. 6 

 Aug. 6 

 Aug. 6 

 Aug. 6 

 Aug. 6 

 Aug. 6 

 Aug. 7 

 Aug. 7 

 Aug. 7 

 Aug. 8 

 Aug. 7 

 Aug. 8 

 Aug. 8 

 Aug. 9 

 Aug. 9 

 Aug. 12 

 Aug. 12 

 Aug. 14 

 Aug. 14 

 Aug. 15 

 Aug. 15 

 Aug. 16 



Duration of 



Incuba- 

 tion Period 

 in Days. 



