CONTENTS 



Page. 



Introduction 1 



Hibernation 1 



Date of entering hibernation , 1 



Number of weevils entering hibernation 5 



Development of immature stages during normal period of hibernation 8 



Mortality of hibernating weevils 11 



Time of greatest mortality during hibernation 14 



' Places of hibernation 17 



Time of emergence from hibernation 19 



Prevention of hibernation ' 22 



Fall destruction of stalks . . , 22 



Crop rotation 24 



Where the weevils first appear -. 24 



Summer broods of the weevil 25 



Mortality of summer broods 28 



Rate of increase of the weevil 31 



Injury to squares in relation to the natural increase of squares. 33 



III 



