CONTENTS. 
Page, 
Introduction 11 
Scope of the present investigation 12 
Nature and extent of injury 13 
Crops affected 15 
Derivation of our leafhopper fauna 16 
Species principally concerned in destructive attacks 18 
General habits 19 
Life history in general 20 
Ecologic relations 21 
Natural enemies 22 
Birds 22 
Evidence as to the relation of birds to leafhoppers 23 
Reptiles and batrachians 31 
Insect enemies 32 
Parasitic insects 33 
Spiders 34 
Remedial measures 35 
Cultural methods 35 
Mowing 36 
Burning 36 
Capturing in hopperdozers or tar pans 37 
Spraying 38 
Some previous records of injury 38 
Records of the Bureau of Entomology 39 
Observations during the season of 1909 41 
Observations during the season of 1910 47 
Systematic position of leafhoppers 50 
Explanation of terms used 51 
The more important species affecting cultivated crops 52 
The yellow-headed leafhopper (Drseculacephala reticulata Sign.) 52 
Distribution 53 
Food plants 54 
Description. 54 
Probably an introduced species 55 
Treatment 55 
Drseculacephala mollipes Say 56 
Distribution and food plants 57 
Description 57 
Life history 57 
Migration 59 
Remedies 59 
Drseculacephala noveboracensis Fitch 59 
Diedrocephala coccinea Forst 60 
The bog leafhopper (Helochara communis Fitch) 60 
Gypona octolineata Say 62 
7 
