THE EUROPEAN CORN BORER AND ITS CONTROL. 53 



On the night of August &-7, 191S, 17 first generation moths were cap- 

 tured at a trap hght. Of these, 7, or 41.2 per cent, were males, and 10, 

 or 58.8 per cent, were females. 



Thus out of a total of 383 first generation adults, 162, or 42.3 per cent, 

 were males, and 221, or 57.7 per cent, were females. 



Second Generation. 

 In April, 1918, two barrels of badly infested cornstalks were collected 

 and placed in the laboratory in order to secure data as to adult emergence, 

 proportion of sexes, etc. From these two cages 307 second generation 

 adults emerged, of which 160, or 52.1 per cent, were males, and 147, or 

 47.9 per cent, were females (see Table XV). 



Table XV,. — Proportion of Sexes and Time of Emergence of Moths, 

 Second Generation. 



Total emergence, 307 adults. 

 Total males, 160, or 52.1 per cent. 

 Total females, 147, or 47.9 per cent. 



