﻿THE GEANARY WEEVIL. 27 



Table 6. — Duration of the pupal stage of the granary weevil 



No. 



Date of— 



Length 

 pupal 



Mean tem- 

 peratures 



No. 



Date of— 



Length 

 pupal 



Mean tem- 

 peratures 























Pupa- 



Emerg- 



stage 



Maxi- 



Mini- 





Pupa- 



Emerg- 



stage 



Maxi- 



Mini- 





tion 



ence 





mum 



mum 





tion 



ence 





mum 



mum 



- 



1919 





Days 



"F. 



°F. 





1920 







Days 



°F. 



°F. 



1 



Oct. 25 



Oct. 30 



5 



91 



66 



2^1 



Oct. 10 



Oct. 



16 



6 



88 



58 



2 



Nov. 1 



Nov. 6 



5 



86 



66 



25 



Nov. 10 



Nov. 



18 



8 



74 



57 



3 



Oct. 27 



Nov. 1 



5 



91 



67 

















4 



Nov. 1 



Nov. 6 



5 



86 



66 





1921 













5 



Nov. 10 



Nov. 17 



7 



81 



59 



26 



Jan. 3 



Jan. 



13 



10 



79 



52 















27 



Jan. 7 



Jan. 



16 



9 



75 



48 





1920 











28 



Jan. 15 



Jan. 



31 



16 



75 



48 



6 



Apr. 26 



May 3 



7 



86 



64 



29 



Jan. 12 



Jan. 



22 



10 



77 



49 



7 



Aor. 30 



May 6 



6 



88 



62 



30 



Jan. 29 



Feb. 



12 



14 



79 



53 



8 



Apr. 28 



May 4 



6 



85 



61 



31 



Feb. 3 



Feb. 



13 



10 



79 



54 



9 



Apr. 29 



May 5 



6 



87 



61 



32 



Feb. 12 



Feb. 



23 



11 



80 



47 



10 



May 9 



May 15 



6 



89 



62 



33 



Mar. 3 



Mar. 



18 



15 



78 



59 



11 



May 12 



May 18 



6 



88 



65 



34 



Mar. 13 



Mar. 



23 



10 



90 



61 



12 



May 13 



...do 



5 



88 



66 



35 



...do..-. 



Mar. 



21 



8 



91 



62 



13 



May 19 



May 24 



5 



88 



63 



36 



Mar. 28 



Apr. 



5 



8 



85 



•62 



14 



July 16 



July 22 



6 



93 



71 



37 



Mar. 25 



Apr. 



2 



8 



87 



63 



15 



Aug. 3 



Aug. 10 



7 



91 



70 



38 



...do.... 



Apr. 



1 



7 



87 



63 



16. 



July 26 



Aug. 1 



6 



92 



70 



39 



Apr. 4 



Apr. 



10 



6 



89 



60 



17 



Aug. 14 



Aug. 21 



7 



93 



69 













Mean 



18 



Aug. 9 



Aug. 15 



6 



94 



70 



40 



Aug. 28 



Sept. 



3 



6 



82 



19 



Aug. 19 



Aug. 25 



6 



95 



69 



41 



- -do.... 



Sept. 



2 



5 



82 



20 



Aug. 21 



Aug. 27 



6 



95 



69 



42 



Aug. 29 



Sept 



3 



5 



84 



21 



Sept. 1 



Sept. 6 



5 



93 



70 



43 



Sept. 17 



Sept. 



22 



5 



77 



22 



Sept. 28 



Oct. 3 



5 



82 



60 



44 



Oct. 31 



Nov. 



7 



7 



68 



23 



Sept. 30 



Oct. 6 



6 



81 



59 















These data indicate that during the warm season of the year, when 

 the mean temperatures vary from a maximum of 85° to 95° F. to a 

 minimum of 61° to 71° F., the pupal stage may require a minimum 

 of 5 days for development. During the hottest summer weather 

 pupal development was completed in from 5 to 7 days. Certain 

 pupae completed their development in 5, 6, and 7 days when the 

 .mean temperature was 77°, 82°, and 68° F., respectively. During 

 the colder season six pupae completed their development in 16, 10, 

 14, 10, 11, and 15 days when the mean temperatures were 61.5°, 63°, 

 66°, 66.5°, 63.5°, and 68.5° F., respectively. 



