THE CODLING MOTH ON PEARS IN CALIFORNIA. 



15 



larvae, in early June, gives some three months for the transformation 

 period of all the overwintering larvae to adults. 



Length of pupal period. — The time spent in the pupal stage varies 

 considerably for different individuals, but all of this brood in 1909 

 required a month or more, the average time being 39.54 days. (The 

 period of emergence of moths lasts some two months^ from the first 

 to the last appearing individuals.) Individual records were started in 

 the spring of 1909 for 128 larvae, but moths emerged from only 68. 

 These records are given in Table I. 



Table I. — Dates of pupation, duration of pupal period, and dates of emergence of moths 

 of the spring brood from overwintering larvae, Walnut Creek, Cal., 1909. 





Date of— 







Date of— 







Date of— 





Indi- 





Pupal 

 period. 



Indi- 

 vidual 

 No. 







Pupal 

 period. 



Indi- 

 vidual 

 No. 







Pupal 

 period. 



vidual 



No. 



Pupa- 



Emer- 



Pupa- 



Emer- 



Pupa- 



Emer- 





tion. 



gence. 







tion. 



gence. 







tion. 



gence. 











Days. 









Days. 









Days. 



1 



Mar. 11 



Apr. 20 



40 



25 



Mar. 27 



Mav 6 



40 



49 



Apr. 4 



May 17 



43 



2 



10 



20 



35 



26 



27 



6 



40 



50 



4 



17 



43 



3 



16 



27 



42 



27 



29 



7 



39 



51 







17 



42 



4 



16 



24 



39 



28 



29 



6 



38 



52 



5 



22 



47 



5 



17 



21 



35 



29 



30 



7 



38 



53 



5 



19 



44 



6 



17 



22 



36 



30 



30 



7 



38 



54 



7 



24 



47 



7 



17 



May 1 



45 



31 



30 



7 



38 



55 



20 



26 



36 



8 



17 



2 



46 



32 



Apr. 1 



6 



35 



56 



21 



26 



35 



9 



18 



11 



54 



33 



1 



7 



36 



57 



20 



25 



35 



10 



18 



2 



45 



34 



1 



8 



37 



58 



20 



27 



37 



11 



18 



1 



44 



35 



1 



9 



38 



59 



22 



29 



37 



12 



18 



3 



46 



36 



2 



9 



37 



60 



22 



24 



32 



13 



19 

 19 



4 

 9 



46 



51 



37 



38. ... : 



2 



2 



9 

 9 



37 

 37 



61 



62 



22 



26 







14 



29 



33 



15 



19 



4 



46 



39 



2 



10 



38 



63 



27 



30 



33 



16 



21 



4 



44 



40 



2 



10 



38 



64 



25 



28 



33 



17 



21 



2 



42 



41 



2 



11 



39 





21 



28 



37 



18 



22 



5 



44 



42 



2 



20 



48 



66 



16 



25 



39 



19 



22 



5 



44 



43 



4 



10 



36 



67 



16 



26 



40 



20 



23 



5 



43 



44 



4 



12 



38 



68 



18 



30 



42 



21 



22 



25 

 25 



27 

 27 



6 

 4 

 5 

 6 



42 



40 

 39 

 40 



45 

 46 

 47 

 48 



4 

 4 



4 

 4 



13 

 13 

 14 

 17 



39 

 39 

 40 

 43 









Ai 



M 



/erage 





39.54 



23 



iximiim _ 





54.00 



24 



M Tiimnm. . 



32.00 













From some 300 larvae put in vials for individual records in Febru- 

 ary, 1910, 118 completed pupation and produced adults. Records of 

 these are given in Table II. As will be seen, the pupal period was 

 shorter for the spring brood in 1910 than was the case in 1909. In 

 1910 the minimum was 21 days, with a maximum of 46, averaging 

 30.86 days for all individuals under observation, as against an average 

 of 39.54 days in 1909. 



