BULLETIN 429, U. S. DEPAETMENT OF AGRICULTURE. 



LENGTH OP LIFE OF MOTHS. 



Observations were made on the length of Ufe of 335 male moths 

 and 393 female moths. The average hfe of the male moths was 6.7 

 days; of the female 8.47 days. The maximum length of hfe of the 

 male moth was 20 days and of the female 22 days. The minimum 

 number of days for each sex was identical — 2 days. 



The records of these observations may be found in Table III. 



Table III. — Length of life of 728 individual male and female codling moths of the spring 

 brood, Roswell, N. Mex., 1912. 



Male. 



Female. 



Male. 



Female. 



Length 

 of life. 



Number 

 of moths. 



Length 

 of life. 



Number 

 of moths. 



Length 

 of life. 



Number 

 of moths. 



Length 

 of Ufe. 



Number 

 of moths. 



Days. 

 2 

 3 

 4 



5 

 6 

 7 

 8 

 9 

 10 

 11 

 12 



2 

 11 

 28 

 73 

 72 

 42 

 41 

 24 

 18 

 14 



5 



Days. 

 2 

 3 

 4 

 5 

 6 

 7 

 8 

 9 

 10 

 11 

 12 



3 



10 

 24 

 34 

 48 

 51 

 54 

 47 

 37 

 23 

 14 



Days. 

 13 

 14 



18 

 20 



2 

 1 



1 

 1 



Days. 

 13 

 14 

 15 

 16 

 17 

 18 

 19 

 20 

 22 



13 

 15 

 5 

 3 

 3 

 2 

 3 

 3 

 1 























335 



393 



Average length of life of male moths, 6.7 days. 

 Average length of life of female moths, 8.47 days. 

 Maximum length of life of male moths, 20 days. 

 Maximum length of life of female moths, 22 days. 

 Minimum length of life of male moths, 2 days. 

 Mini mum length of life of female moths, 2 days. 



THE FIRST GENERATION. 



THE FIRST BROOD OF EGGS. 



Length, of incuhation. — Observations on the length of incubation 

 covered a period of one month, extending from April 26 until May 

 26, being the time when the eggs of this generation occurred in the 

 field in greatest numbers. 



The average length of time from the date of deposition until the 

 appearance of the red ring was 4.2 days; the maximum, 7 days; the 

 minimum, 2 days. The average length of the duration of the red 

 ring was 2.47 days; the maximum, 5 days; minimum, 1 day. For 

 the duration of the black spot is found an average of 2.36 days, while 

 the maximum and minimum periods are identical with the correspond- 

 ing periods of the red ring. 



For the period of time covering the duration of incubation, or the 

 time from date of deposition to date of hatching, an average of 9.05 

 days is found. The maximum is 13 days; minimum, 5 days. These 

 records may be found in Table IV. 



