. 



CLASSIFICATION 



Suborder Terebrantia (Phytophaga, Sessiliventres). Abdomen 

 broadly attached to the thorax (sessile). Trochanters of posterior 

 legs two-segmented. Ovipositor modified for boring, sawing or cutting. 

 Larvae with complex mouth parts, frequently caterpillar-like, with three 



FIG. 29. Papilio troilus. A, larva; B, larva suspended for pupation; C, chrysalis. Nat- 

 ural size. 



pairs of thoracic legs and seven or eight pairs of abdominal prolegs. 

 Phytophagous or parasitic. Saw-flies, gall-flies, ichneumon-flies, etc. 

 Example, the pigeon horn-tail, Tremex (Fig. 30). 



Suborder Aculeata (Heterophaga, 

 Petiolata.) Abdomen petiolate or 

 subpetiolate (with a deep constriction 

 between the thoracic and abdominal 

 regions). First abdominal segment 

 (propodeum) transferred to the tho- 

 racic region. Trochanters of posterior 

 legs one-segmented. Ovipositor often 

 modified to form a sting. Larvae 

 apodous. Ants, bees, wasps, etc. Ex- 

 ample, the honey bee, Apis (Fig. 284). 



19. Diptera. Metamorphosis indi- 

 rect. Mouth parts typically SUCtorial, FIG. 30. Tremex columba. A, imago; 

 v j'f* j r i B, larva (with parasitic larva of Thalessa 



but modified for piercing, lapping, attache d). Natural size.-After R ILEY . 



rasping, etc. Prothorax and meta- 



thorax small, mesothorax predominant. Tarsi usually five-segmented. 

 One pair of wings (meso thoracic) , membranous, transparent, with 

 few veins; wings rudimentary or absent, however, in most of the 



