CONTENTS. 



Page. 



Introduction 39 



History of the sorghum midge in America 40 



Distribution 42 



Investigations carried on in Louisiana and Texas during 1908 and 1909 42 



Host plants 44 



Descriptions 45 



The adult .' 45 



The egg 47 



The larva 47 



The pupa 48 



The ' ' cocooned larva " 48 



Life history and habits 49 



Emergence 49 



Copulation 49 



Oviposition 50 



Location of the egg 51 



Location of the larvae 52 



Location of the pupa 52 



Number of generations 52 



The life cycle 52 



Length of life of adult 53 



Seasonal activity 53 



Hibernation 54 



Relation of Johnson grass to the midge problem 55 



Natural enemies 55 



Parasites 55 



Predaceous enemies 57 



Remedial measures 58 



Destruction of Johnson grass 58 



Clean harvesting 58 



Destroying seed heads of first crop 58 



Bagging seed heads 58 



in 



