THE CODLING MOTH IN THE YAKIMA VALLEY. 



9 



Number of eggs 'per female. — The average number of eggs per female 

 in the cages from which the data given in Table 3 were secured was 

 6.36, 300 females depositing a total of 1,907 eggs. 



Length of life of moths. — Records of the length of life of 285 male 

 moths and 300 females were obtained from the oviposition cages, 

 and these are given in Table 4. 



Table 4. 



-Length of life of male and female codling moths of the spring brood, 

 Yakima. Wash., 1919. 



Male. 



Female. 



Male. 



Female. 



Male. 



Female. 



Length 

 of life. 



Num- 

 ber of 

 moths. 



«|s 



Length 

 of life. 



Num- 

 ber of 

 moths. 



Length 

 of life. 



Num- 

 ber of 

 moths. 



Length 

 of life 



Num- 

 ber of 

 moths. 



Length 

 of life. 



Num- 

 ber of 

 moths. 



Days 

 1 

 2 

 3 

 4 

 5 

 6 

 7 

 8 

 9 

 10 

 11 



1 

 2 

 5 

 12 

 9 

 7 

 12 

 11 

 8 

 13 

 10 



Days 

 1 

 2 

 3 

 4 

 5 

 6 

 7 

 8 

 9 

 10 

 11 





 4 

 1 

 3 

 3 

 7 

 5 

 9 

 6 

 11 

 8 



Days. 

 12 

 13 

 14 

 15 

 16 

 17 

 18 

 19 

 20 

 21 

 22 



10 

 16 

 13 

 16 

 18 

 14 

 12 



5 

 14 



7 

 17 



Days. 

 12 

 13 

 14 

 15 

 16 

 17 

 18 

 19 

 20 

 21 

 22 



7 

 18 



8 

 19 

 16 

 27 

 18 

 19 

 28 

 13 

 23 



Days. 

 23 

 24 

 25 

 26 

 27 

 28 

 29 



Total.. 



12 

 4 

 9 



15 

 8 

 5 

 



Days. 

 23 

 24 

 25 

 26 

 27 

 28 

 29 



Total.. 



13 

 6 



8 

 8 

 9 

 2 

 1 



285 



300 



Average length of life of male moths, 15.33 days; female moths, 16.91 days. 

 Maximum length of life, male moths, 28 days; female moths, 29 days. 

 Minimum length of life, male moths, 1 day; female moths, 2 days. 



THE FIRST GENERATION. 



EGGS OF THE FIRST BROOD. 



Time of egg deposition. — Spring-brood moths in the insectary 

 began ovipositing May 21, and with the exception of two days 

 eggs were deposited every 

 day until June 24. These 

 two days were May 29 and 30, 

 which were abnormally cold. 

 The oviposition record is de- 

 lineated in Figure 3. As 

 shown on page 64, the ma- 

 jority of the eggs are depos- 

 ited between 3 and 9 p. m. 

 The average temperature for 

 this 6-hour period is there- 

 fore given on the diagram, 

 instead of the usual average 

 daily temperature. A refer- 

 ence to Tables 52 and 53 

 will show also that as the 

 temperature decreases the 

 number of eggs deposited 

 diminishes, until at 60° F. fig. 3 

 and lower it is rare for any 

 eggs at all to be deposited. Figure 3 shows graphically how closely 

 the number of eggs deposited follows the fluctuations in the tempera- 

 ture curve. The majority of the eggs of the first brood were deposited 



Time of deposition of eggs of the first brood of the 

 codling moth at Yakima, Wash., 1919. 



