22 



BULLETIN 926, TJ. S. DEPARTMENT OF AGRICULTURE. 



Table XI. — Fecundity record of individual hibernated females of the boll weevil 

 fertilized in spring under field conditions on upland cotton. 





Num- 

 ber eggs 



de- 

 posited 

 nor- 

 mally. 



Progeny produced by individual females. 



Per- 



Date oviposition 



Males. 



Females. 



Both sexes. 



centage 

 punc- 

 tured 



began. 



Wee- 

 vils 

 bred. 



Weevil 

 days. 



De- 

 velop- 

 mental 

 period. 



Wee- 

 vils 

 bred. 



Weevil 

 days. 



De- 

 velop- 

 mental 

 period. 



Total 

 wee- 

 vils 

 bred. 



Total 

 weevil 

 days. 



Period 

 both 

 sexes. 



squares 

 produc- 

 ing 



adults. 



Mav29 



28 

 218 

 33 

 80 

 65 

 63 

 49 

 68 

 70 

 88 

 97 

 54 



10 

 15 

 7 

 4 

 2 

 6 

 1 

 7 

 6 

 5 

 5 

 5 



188 



297 



137 



93 



43 



132 



22 



170 



125 



120 



104 



105 



Days. 

 20.8 

 21.2 

 19.6 

 23.2 

 21.5 

 22 

 22 



24.2 

 20.8 

 24 

 20.8 

 21 



6 



7 

 3 

 7 

 

 4 

 1 

 3 

 7 

 3 

 7 

 4 



124 



148 

 60 



166 







92 



23 



70 



152 

 67 



152 

 91 



Days. 

 20.6 

 21.1 

 20 

 23.3 





 23 

 23 



23.3 

 21.7 

 22.3 

 21.7 

 22.7 



16 

 22 

 10 

 11 



2 

 10 



2 

 10 

 13 



8 

 12 



9 



312 

 445 

 197 

 259 



43 

 224 



45 

 240 

 277 

 187 

 256 

 196 



Days. 

 19.5 

 20.2 

 19.7 

 23.5 

 21.5 

 22.4 

 22.5 

 24 



21.3 

 23.3 

 21.3 

 21.7 



57.1 



Do 



10.08 



Mav 31 



30.3 





13.7 



Do 



13.07 





15.8 





4.08 





14.7 



Do 



18.5 



June 12 



11.4 



Do 



13.6 





13.6 







Total 



913 



76.08 

 218 

 28 



73 



1,536 



21.7 

 24.2 

 19.6 



52 



1,145 



20.2 



23.3 







125 



2,681 









21.7 



24 



19.5 



17.99 



Minimum 



15 



1 





7 

 





22 

 2 





57.1 

 4. OS 



SUMMARY OF THE DEVELOPMENTAL PERIOD OF THE FIRST- 

 GENERATION BOLL WEEVILS IN UPLAND COTTON SQUARES 

 UNDER FIELD CONDITIONS. 



Table XII gives a summary of the period of development in up- 

 land cotton squares of first-generation weevils under field condi- 

 tions, together with the temperature and humidity records. The 

 average period of development in the infested squares while the 

 squares remained on the growing cotton plants is shown to be 10.9 

 days. During the time the infested squares were on the ground or 

 after they had dropped off the plant the average period of develop- 

 ment is shown to be 11.4 days. The average maximum soil tem- 

 perature was 103.7° F. Since it has been demonstrated that the 

 boll weevil develops most rapidly under a mean temperature of 84° 

 F., the higher temperatures experienced while the square is on the 

 soil retard the developing process and prolong the developmental 

 period of the weevil. Also high soil temperatures are directly re- 

 sponsible for the death of large numbers of immature weevils. At 

 Madison it was observed that a very high percentage of teneral 

 weevils was killed by the heat before the weevils could make an 

 emergence hole in the square. 



