114 



DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



An attempt has been made to follow the plan of presentation as 

 given by Messrs. Jenne and Hammar in their respective studies on 

 the codling moth. 1 



SEASONAL-HISTORY STUDIES OF 1909. 



SPRING BROOD OF PURE. 



The record for this brood was made from larvae collected January 

 2 in the field from under the bark on apple trees and placed in sepa- 

 rate vials for an individual pupation record. Table I records the 

 time of pupation, time of emergence, and length of pupal period. 



Table I. 



-Spring brood of pupae. Length of the pupal stage for ivintering larvae col- 

 lected in January, 1909, from banded trees. 





Date of— 







Date of— 





No. Of 



individ- 





Length 

 of pupal 



No. of 



individ- 





Length 

 of pupal 











ual. 



Pupa- 



Emer- 



stage. 



ual. 



Pupa- 



Emer- 



stage. 





tion. 



gence. 







tion. 



gence. 











Days. 









Days. 



1 



Feb. 20 



Apr. 17 



56 



17 



Mar. 26 



May 3 



38 



2 



Mar. 4 



...do 



48 



18 



Mar. 27 



...do 



37 



3 



...do 



...do 



53 



19 



Mar. 29 



Apr. 28 



30 



4 



Mar. 5 



...do 



52 



20 



...do 



May 3 



35 



5 



Mar. 8 



Apr. 28 



51 



21 



...do 



...do 



35 



6 



Mar. 9 



Apr. 26 



48 



22 



Mar. 30 



May 6 



37 



7 



...do 



...do 



48 



23 



Apr. 1 



May 1 



30 



8 



...do 



Apr. 28 



50 



24 



...do 



May 3 



32 



9 



Mar. 11 



...do 



48 



25 



...do 



...do 



32 



10 



Mar. 12 



Apr. 29 

 May 1 



48 



26 



...do 



...do 



32 



11 



Mar. 13 



49 



27 



...do 



...do 



32 



12 



Mar. 15 



May 3 



49 



28 



Apr. 6 



May 10 



34 



13 



Mar. 23 



...do 



41 



29 



Apr. 9 



May 11 



32 



14 



Mar. 24 



Apr. 28 



35 



30 



Apr. 12 



May 4 



22 



15 



...do 



...do 



35 



31 



...do 



May 17 



35 



16 



...do 



May 1 



38 











Thus the pupal stage varied from 22 to 56 days, with an average 

 of 40.22 days. The first pupation occurred February 20 and the 

 last April 12, while the first adult emerged April 17 and the last 

 May 17. The pupal period, therefore, occupied the time between 

 February 20 and May 17, or 87 days. No record was kept with regard 

 to the sexes of either larvae or adults. Table II shows the variations 

 in the length of the pupal stage and is a summary of Table I. 



Table II. — Spring brood of pupae. 



Variations in the length of the pupal stage as recorded 

 in Table I. 



Number 

 of pupae. 



Days. 



Number 

 of pupae. 



Days. 



Number 

 of pupae. 



Days. 



Number 

 ofpupae. 



Days. 



1 

 2 

 5 



1 



22 

 30 

 32 

 34 



5 

 2 

 2 

 1 



35 

 37 

 38 

 41 



4 

 2 

 1 

 1 



48 

 49 

 50 

 51 



1 

 2 



1 



52 

 53 

 56 



This record is for only 31 pupae and is somewhat irregular. 



i Bull. 80, Pts. I and VI, and Bui. 115, Pt. I, Bur. Ent., U. S. Dept. Agr. 



