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vils. It seemed to be more powerful than the male, breaking through 

 the weevil's skeleton with apparent ease. On several occasions it 

 was found to eat 8 or 10 weevils a day. During her period of con- 

 finement in the cage she deposited a large batch of eggs, and in the 

 course of about three weeks she destroyed altogether a total of 80 

 weevils. 



Some species of Mantispa also probably devour a few weevils in the 

 field, but the writer has never seen one in the act. 



BIRDS. 



There can be no doubt that birds are exceedingly valuable assist- 

 ants to man in reducing the numbers of many insect pests. In order 

 to determine to what extent they feed upon the boll weevils, it is nec- 

 essary that an extensive study be made of the stomach contents of all 

 birds that may be found in cotton fields. To be at all conclusive 

 such studies must be made in numerous localities and during more 

 than one season. To accomplish this it is deemed advisable to reserve 

 for the present the results of the study of the relation of birds to the 

 weevil problem, that a more complete treatment of the question may 

 be made in some future publication. 



METHODS OF COMBATING THE WEEVIL. 



The difficulties in the way of controlling the boll weevil lie as much 

 in its habits and manner of work as in the peculiar industrial condi- 

 tions involved in the production of the staple in the Southern States. 

 The facts that the weevil lives in all stages except the imago within 

 the fruit of the plant, well protected from any poisons that might be 

 applied, and in that stage takes food normally only by inserting its 

 snout within the substance of the plant; that it is remarkably free 

 from parasites or diseases ; that it frequently occupies but 14 days for 

 development from egg to adult, and the progeny of a single pair in a 

 season may reach 134,000,000 individuals; that it adapts itself to 

 climatic conditions to the extent that the egg stage alone in Novem- 

 ber may occupy as much time as all the immature stages together in 

 July or August, are factors that combine to make it one of the most 

 difficult insects to control. It is consequently natural that all the 

 investigations of the Division of Entomology have pointed toward 

 the prime importance of cultural methods of controlling the pest. 

 All other methods must involve some direct financial outlay for 

 material or machinery, and are consequently not in accord with 

 labor conditions involved in cotton production in the United States. 

 Moreover, the cultural methods are in keeping with the general tend- 

 ency of cotton culture; that is, to procure an early crop, and at the 

 same time have the great advantage of avoiding damage by a large 

 number of other destructive insects, especially the boll worm. Never- 

 theless, it must not be understood that attention has not been paid 



