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under inductive photo^eriods than did those from College Station or Presidio. 

 It was concluded that the boll weevil is becoming adapted to the environment 

 of the High Plains and a distinctive photoperiodic race of the species may have 

 already evolved in this area. It is suggested that a new type of approach for 

 reducing diapausing boll weevils might be particularly effective in the High 

 and Rolling Plains. This approach would have two phases. Phase I would be 

 directed towards killing the last reproductive generation of adult females 

 before they lay the eggs that give rise to the potentially overwintering adults. 

 This would be -.ccoaplished with insecticidal applications made at 5-day inter- 

 vals during September. Phase 2 would have as its objective the killing of any 

 diapausing adults in October that may have survived earlier insecticidal treat- 

 ments or that may have developed from eggs laid between applications in Seii "ember. 



849. , and Adkisson, P. L. 1970. Seasonal rates of increase for a population 

 of the boll weevil, Anthonomus grandis , in the High and Rolling Plains 

 of Texas. Ann. Entomol. Soc. Am. 63: 1696-1700. 

 Life, fertility, and life-expectancy tables, were computed for 13 boll weevil 

 cohorts reared in the field cages and in an insectary. The increase in female 

 offspring per female per week ranged from 1.56 for adults produced from eggs 

 deposited Aug. 16, 1966, to 0.63 for eggs deposited Sept. 26, 1966. However, 

 the number of female offspring produced per female per generation ranged from 

 20.6 for adults emerging from eggs deposited Aug. 30, 1966, to 0.02 for eggs 

 deposited Oct. 3, 1966. Seasonal life expectancy for eggs during 1966 ranged 

 from about 1 to 7 weeks for eggs deposited Aug. 2 and Sept. 29, respectively. 

 However, the life expectancy of teneral adults ranged from almost 3 to 10 weeks 

 during this same period. This, adults had a greater life expectancy than eggs. 

 Adults emerging from cohorts started after mid-August had lower mortality rates 



