76 



BULLETIN 429j TJ. S. DEPARTMENT OF AGRICULTURE. 



the third generation, showing the average length of the periods 

 of each stage. The sum of the averages of the stages is found to be 



—03 



e/ 



9/ 



^1 



31 



s/ 



ir/ 



^^' 



m ?/ 



'< a 



s 



s 



ir 



e 



z 

 1 





~ 



— 



~ 



^ 





' 











~ 



~" 





"" 







~ 













1 



~ 







— 







— 





~ 



~ 





— 







— 







p 



p 





— 



— 



-| 

































































































1 

































































































1 































































































/ 



I 































































































[ 

































































































' 

































































































































































































t 

































































































I 

































































































/l 































































































1 



1 

































































































1 

































































































































































































hi 































































































, 



'/ 































































































' 



( 































































































y 



/ 































































































V 



' 





























































































^ 





' 



























































































\ 











oe 



63 



es 



' 3-3 

 S3 

 *? 



ez 



33 



13 

 03 



e/ 

 Ke/ 



t/ 



31 

 II 

 01 



s 



8 

 Z 

 9 

 S 

 * 

 C 

 3 





























































































N 

































































































^ 



1 



























































































<^ 

































































































V 





/ 

































































































K 































































































^ 































































































■^ 



N 































































































} 





> 































































































' 





























































































s 































































































/ 





7 



























































































•f 





























































































s 

































































































> 































































































\ 



' 































































































' 



s, 



























































































^ 





- 

























































































.' 



f 

























































































^ 



" 







s 



^ 















































































^ 







.« 





































































































































































- 



^ 



i» 



















































































^ 



^ 



— 



■* 





















































































" 



/ 





















































































_ 



— 



r 





























































































— 



■- 



^ 





- 























































































« 



„ 



-t 



— 























































































'" 



■" 



— 





— 







_ 























































































s 











^ 



^ 



























































































/ 





















. 





































































^ 



^ 





"" 





















































































IC 



oe 











"> 







































































































" 



-' 



r: 



— 





— 



_ 





^ 



_ 























































































_ 





p- 



— 





— 



~ 



































































i.3 















' 







- 





— 





^ 



-. 



































































































' 





— 































































93 

















































-■ 



?7 



— 







— 











" 



- 





























S3 



























































- 





































































































- 



[-. 



































































































■* 



-■ 



H 



M. 







































































































^ 



■* 



































































































^ 



r- 

















03 















































































/ 





































































































■^ 





\ 



^ 













^*' 























































































\< 



/ 

































































































f 



>s 





































































































\ 

































































































,>« 



































































































N 











■ 



























































































i 

































































































J*" 



































































































■> 



>> 





































































































/ 



































































































si 





































































































1^ 





^ 































































































^!s 





^ 







































































































42.9 days, while the average length of the total life cycle of this gen- 

 eration is 43.11 days, a difference of but 0.2 days. 



