38 BULLETIN 429, U. S. DEPARTMENT OF AGMCiTJLTXTKE. 



SPRING BROOD OF MOTHS. 



Time of emergence. — The emergence of moths of the spring brood 

 was found to begin as early as April 7 and to continue more or less regu- 

 larly until the first part of June. However, a maximum emergence 

 was found to occur in the 10-day period between April 17 and 27, in 

 which a total of 1,334 moths emerged. The emergence during this 

 period represents 58.33 per cent of the entire number which emerged 

 during 1913, covering a period of 57 days. Further examination of 

 Table XXXIII will show that of 7,343 larvae, the entire number col- 

 lected, a sum total of 5,216 moths emerged, being equivalent to 71.04 

 per cent of the larvae It may be noted in this connection that 56.19 

 per cent of the moths emerged during 1912, while 43.81 per cent 

 emerged in the spring of 1913. 



