54 



BULLETIX 932, U. S. DEPABTMENT OF AGRICTJXTUKE. 



Table XXXIV. — Time of deposition, length of incubation, and time of hatching 



of eggs of the first brood of the codling moth, Grand Junction, Colo.. 1916 



Continued. 



Obser- 

 vation 

 Xo. 



Num- 

 ber of 

 eggs de- 

 posited 



Date— 



Xumber 



of eggs 



hatched. 



Appearance of— 



Incu- 

 bation 

 period. 



".IT ■— J g a o C , k Hatched. 



Red 

 ring. 



Black 

 spot. 



7S 

 79 

 SO 

 81 

 82 

 83 

 84 

 85 



Total. 



35 

 3 

 3 



15 

 8 



June 2S 

 June 29 

 June 30 

 Julv 1 

 July 2 



June 30 

 Julv 1 

 Julv 3 

 ...do.... 

 July 4 



July 3 

 July 4 



July 4 

 July 5 



12 

 1 

 

 9 

 5 

 2 

 

 1 

 



Days. 



I 



3 

 2 

 2 



Days. 

 5 

 5 



5 

 5 



Days. 



6 

 

 6 

 6 







6 

 



July 6 

 July 7 



July 7 

 July 8 

 July 9 



4 

 1 

 2 



July 3 

 July 5 

 July 7 









July 8 



July 10 



July 11 



3 J ' "~S 











8,774 



6,597 









Aver...!. . 



2.62 | 6.6S 

 10 11 



7.32 

 14 

 6 



Max 

 Mm 







I 













Length of incubation. — The length of incubation and embryolog- 

 ical changes of eggs of the first brood are given in Table XXXIV 

 as follows : Average number of days from date of deposition to the 

 appearance of the red ring 2.62 days, maximum 10 days, minimum 1 

 day ; average appearance of the black spot from time of deposition 

 6.68 days, maximum 11 days, minimum 5 da}'s; average incubation 

 period 7.32 days, maximum 14 days, minimum 6 days. 



Laby^ of the Feest Bkood. 



Time of hate Jung. — The time of hatching of eggs of the first brood 

 will be found in Table XXXIV. The first eggs of this brood 



hatched June 1; the 

 last, July 11. Thus 

 the period of incu- 

 bation extended over 

 one month, the maxi- 

 mum number hatch- 

 ing on June 16, or 

 15 days after the 

 first larvae appeared. 

 The rate of hatching 

 is shown diagram- 

 matically in figure 

 21, in which it will 

 be noted that the 

 majority of the 

 larvae hatched about 

 the middle of the 

 hatching period. 

 Length of the feeding period, stock- jar method. — The summarized 

 account of the length of the feeding period of 817 larvae of the first 



















I 



A 





es 



7S 



600 

 SSO 

 600 

 +SO 



Q.300 



- 



< ZOO 

 ISO 















y 



A 



V 



rfi 







1 \ *-» 



I 1 



r 



\ 



1 \ 



f 









j 











70 





/ 1 





!_ 



1 











1 \ f % 1 





A 













6S 



1 \ 1 \l 





















\r 



. 





*>\ 











1 





































\/ 1 



' ! i 1 1 































SO 



so 

























w> 









V- 



vz^__ 









i ; 



„ . 



t- < 



> 









■ 





« 



< 



4 



i 





Fig. 21. — Time of batching of eggs of the first brood of 

 the codling moth, Grand Junction, Colo., 1916. 



