68 THE MEXICAN COTTON-BOLL WEEVIL. 



Table XXV. — Duration of the pupal stage of the boll weevil. 



1 The extremes were 2.8 and 3.9 days. 



PERCENTAGE OF WEEVILS DEVELOPED FROM INFESTED 



SQUARES. 1 



During the season of 1902 part of the many squares gathered in 

 infested fields for the rearing of weevils were followed to learn some- 

 thing of the percentage which produced normal adults. No exam- 

 ination was made for those not yielding a weevil. The decay of the 

 square during the period from its falling to the maximum time that 

 must be allowed for weevils to escape normally so obliterates any 

 small amount of work by a larva that it is difficult, even with exam- 

 ination, to determine accurately the number of dead small larvae. 



Table XXVI.— Percentage of boll iveevils from infested squares. 



Locality. 



Approximate date. 



Number 



of 

 squares. 



Number 



of 

 weevils. 



Percentage 



of squares 



producing 



weevils. 



Victoria, Tex 



Guadalupe, Tex. 



Victoria, Tex. 



Do 



Do 



Do 



Total. 



July to August. 

 August 



1903. 



June 



June to August 



August to September. 



June to September. 



1,125 

 387 



334 

 873 

 368 



4,038 



360 

 108 



106 

 355 

 192 



1,590 



32.0 

 28.0 



32.0 

 41.0 

 52.0 



49.3 

 39.4 



It seems safe to conclude that throughout the season fully one- third 

 of the squares which fall after receiving weevil injury may be expected 

 to produce weevils. 



» From Bui. 51, Bureau of Entomology, p. 92. 



