CODLING MOTH IN SANTA CLARA VALLEY. 



151 



From Table XXXVIII it is seen that the maximum egg stage was 

 15 days, the minimum 10, and the average 12.77 days. The average 

 time before appearance of the red ring was 3 days, and the time 

 before appearance of the black spot 11 days. 



FIRST BROOD OF LARV.E. 



Time of hatching. — The first larva to appear from eggs laid by cap- 

 tive moths hatched June 16. In the field at this time some full- 

 sized larvae were noticed, which were in all probability just-hatched 

 larvae about May 1, but, as has been stated before, the captive moths 

 refused to deposit eggs before June 1. From eggs laid after this 

 date 16 larva? hatched and were placed on apples to get data on the 

 feeding period and post-larval stage. Only six of these transformed 

 into the pupae and Table XXXIX records their larval history. 



Table XXXIX. — First-brood larvae: Feeding period and length of the post-larval 



stage. 



a Larva spun cocoon in apple. 



The average length of the total larval stage was 34.67 days, includ- 

 ing the time taken by the larva to spin its cocoon after leaving the 

 apple, which is the post-larval stage. As this period varies consider- 

 ably, in the above six instances from 1 to 18 days, the true larval 

 stage or feeding period is found by simply taking the time of larval 

 existence until the worm leaves the apple. In the instance of larva 

 No. 3 the cocoon was spun inside the apple, so the time spent in feeding 

 could not be determined. The average time taken by the other five 

 to attain full growth was 25.8 days, with a maximum of 28 and a 

 minimum of 24 days. 



Number of larvse developing in each apple. — Several larvae entered 

 the same apple in numerous instances, but never more than two 

 developed. In the orchard usually but one larva is found in each 

 apple, although the entrance holes of several often can be observed. 

 An apple from which a larva of the first generation has issued may 

 later contain a larva of the succeeding generation. 



