48 



BULLETIN 932, U. S. DEPARTMENT OF AGRICULTURE. 



Table XXX. — Length of the pupal stage of pupce of the spring brood of the 

 codling moth, Grand Junction, Colo., 1916 — Continued. 



Date of 

 pupa- 

 tion. 



Num- 

 ber 

 of 

 indi- 

 vid- 

 uals. 



Length of the pupal stage in specified days. 



13 



14 



16 



17 



18 



19 



2(1 



21 



22 



23 



24 



3 

 2 

 2 



1 



25 



26 



1 



27 



28 



29 



3:) 



31 



32 



34 



36 



May 15 



16 

 17 

 18 

 19 

 20 

 21 

 22 

 23 

 24 

 25 

 27 

 28 

 29 

 30 

 31 

 June 2 

 4 

 6 

 12 



Pupae 



4 

 3 

 7 

 9 

 4 

 1 

 2 

 3 

 3 

 5 

 2 































1 



4 

 3 

 2 





















... 

































1 



... 



















3 

 1 

 1 



1 



1 





























1 





































































2 

 1 







































1 

 2 





1 









































1 



























2 

 1 



4 

 1 



2 



1 



2 



















































1 











4 

 2 

 5 















































1 

 2 

 6 







































1 



































6 

 1 

 1 

 2 

 2 

 1 











































1 





































1 

































T 



1 

 1 



1 

 1 



















































































































































390 



1 



2 



3 



11 



10 



2 



3 



6 



6 



12 



9 



8 



37 



80 



77 



58 



40 



18 



4 



2 



1 



Average length of pupal stage 26. 8 



Maximum length of pupal stage 36 



Minimum length of pupal stage 13 



MOTHS OF THE SPRING BROOD. 



Time of emergence. — The tabulated data of the time of emergence, 

 of 4,808 moths of the spring brood are given in Table XXXI. The 

 first of these emerged May 10 and the emergence period continued 

 until June 28, when the last moth of this brood issued. The emer- 

 gence reached its maximum on May 24, on which day 552 moths ap- 

 peared. On the preceding day, May 23, the next highest in number, 

 432 moths, issued. The retardation of emergence, as caused by ad- 

 verse climatic factors on May 20, is readily seen by the marked 

 decrease in emergence from 309 moths May 19 to 3 moths May 20. 

 The daily rate of emergence is shown in figure 19. 



Table XXXI. — Time of emergence of codlmg moths of the sprint/ brood, Grand 



Junction, Colo, 1016. 



Date of 



X um- 



Date of 



Num- 



Date of 



Num- 



Date of 



Num- 



Date of 



Num- 



emer- 



ber of 



emer- 



ber of 



emer- 



ber of 



emer- 



ber of 



emer- 



ber of 



gence. 



moths. 



gence. 



moths. 



gence. 



moths. 

 169 



gence. 



moths. 



gence. 



moths. 



May 10 



3 



May 21 



13 



June 1 



June 11 



74 



June 21 



1 



11 



10 



22 



36S 



2 



80 



12 



58 



22 



5 



12 



21 



23 



432 



3 



146 



13 



42 



23 



1 



13 



49 



24 



052 



4 



150 



14 



43 



24 



3 



14 



8 



25 



151 



5 



120 



15 



29 



25 



2 



15 



4 



26 



135 



6 



97 



16 



26 



26 



1 



16 



39 



27 



160 



7 



45 



17 



17 



27 







17 



36 



28 



274 



8 



86 



IS 



17 



28 



1 



18 

 19 



162 

 309 



29 

 30 



217 

 283 



9 

 10 



79 

 53 



19 

 20 



11 

 14 







Total ... 



4,808 



20 



3 



31 



179 















