TABLE OF CONTENTS 



PAGB 



Introduction v 



List of Plates xix 



List of Text Illustrations xxi 



Order Hymenoptera ....... i 



Table of Suborders and Superfamilies .... 2 



The True Bees (Superfamily Apoidea) ... 4 



Life History of a Bumble Bee (Bombus fervidus) . 12 



Wasps 18 



The Solitary Wasps (Superfamily Sphecoidea) . .18 

 Life History of a Digger Wasp (Sphecius speciosus 



Say.) 22 



The Social Wasps and Their Allies (Superfamily 



Vespoidea) 25 



Typical Life History 33 



Life History of a Parasitic Wasp (Lcelius trogoder- 



matis) 34 



The Ants (Superfamily Formicoidea) . . . 37 



Typical Life History 48 



The Proctotrypoid Parasites (Superfamily Proctotry- 



poidea) 49 



The Gail-Flies (Superfamily Cynipoidea) ... 53 



The Chalcis Flies (Superfamily Chalcidoidea) . . 56 

 Life History of a Chalcis Fly (Euplectrus comstocki 



How.) 57 



The Ichneumon Flies (Superfamily Ichneumonoidea) 6l 

 Life History of an Ichneumon Fly (Pimpla inqui- 

 sitor) 64 



The Horn-Tails (Superfamily Siricoidea) ... 69 



Life History of a Horn-Tai\(Phyllcecus integer) . 71 



The Saw-Flies (Superfamily Tenthredinoidea) . . 73 

 Life History of the Pear Slug ( Eriocampoides 



limacina) 76 



The True Flies (Order Diptera) 79 



xi 



