48 



BULLETIN 932, U. S. DEPAETMEXT OE AGRICULTURE. 



Table XXX. — Length of the pupal stage of pupa? of the spring brood of the 

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



Date of 

 pupa- 

 tion. 



Num- 

 ber I 



Length of the pupal stage in specified days. 



of 

 indi- 

 vid- 

 uals. 



13 



14 



16 



17 



18 



19 



20 



21 



22 



23 



24 



25 



26 



27 



28 



29 



.30 31 



32 



34 36 



May 15 

 16 



17 

 18 

 19 

 20 

 21 

 22 

 23 

 24 

 25 

 27 

 28 



4 

 3 



7 

 9 

 4 

 1 

 2 

 3 

 3 

 5 



1 



" 















3 

 2 

 2 



1 



1 

































1 

 4 

 3 

 2 























































1 



... 



















3 



1 

 1 



1 



1 





























1 



































































2 



1 





































1 

 2 





1 





































1 

























?, 



1 



2 



























2 

 4 

 2 









\ 





















1 



















































1 

 2 

 6 



1 

 2 



































29 5 







1 

































30 



31 



June 2 



4 



6 



12 



Pupse 



6 

 1 

 1 

 2 

 2 

 1 











































1 





































1 

































Y 



1 

 1 



1 

 1 

















































































































































390 



i 



2 



3 



11 



10 



2 



3 



6 



6 



12 



9 



8 



37 



80 



77 



58 



40 



18 



4 2 1 



Days. 



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 maxirnum 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 codling moths of the spring brood. Grand 



Junction, Colo, 1916. 



Date of 

 emer- 

 gence. 



Num- 

 ber of 

 moths. 



Date of 

 emer- 

 gence. 



Num- 

 ber of 

 moths. 



Date of 

 emer- 

 gence. 



Num- 

 ber of 

 moths. 



Date of 

 emer- 

 gence. 



XT 



Num- 

 ber of 

 moths. 



Date of 

 emer- 

 gence. 



Num- 

 ber of 

 moths. 



May 10 

 11 

 12 

 13 

 14 

 15 

 16 

 17 

 18 

 19 

 20 



3 



10 

 21 

 49 



8 



4 



39 



36 



162 



309 



3 



Mav 21 

 * 22 

 23 

 24 

 25 

 26 

 27 

 28 

 29 

 30 

 31 



13 

 36S 

 432 

 552 

 151 

 135 

 160 

 274 

 247 

 2S3 



179 



June 1 

 2 

 3 



4 

 5 

 6 



8 

 9 

 10 



169 

 80 

 146 

 150 

 120 

 97 

 45 

 86 

 79 

 53 



June 11 

 12 

 13 

 14 

 15 

 16 

 17 

 18 

 19 

 20 



74 

 58 



42 

 43 

 29 

 26 

 17 

 17 

 11 

 14 



June 21 

 22 

 23 

 24 

 25 

 26 

 27 

 2S 



1 

 5 

 1 

 3 

 2 







Total ... 



4, SOS 



