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CHAPTER XIII. 



HYMENOPTERA. TEREBRANTIA. 



THE first section of Hymenoptera, TEREBRANTIA, is 

 divided into two subsections, named from the food of 

 the larvae, *PHTTOPHAGA (<vrov, phyton, a plant; tyayw, 

 phago, to eat), and ENTOMOPHAGA (SVTOJUOC, entomos, an 

 insect). PHTTOPHAGA consists of the Sawflies and the 

 Woodborers ; ENTOMOPHAGA contains the gall-making 

 insects, f the Ichneumons (parasites which lay their eggs 

 in the bodies of other living insects), and the Ruby-tails. 



The insects belonging to these two subsections can at 

 once be distinguished from each other by their waists 

 being large or small. That is to say, while in the Saw- 

 flies and Woodborers (PHYTOPPAGA) the abdomen is 

 attached to the thorax by its whole width (see PL VI., 

 figs. 1, 2), in the Ichneumons, Gallflies, &c. (see PL I., 

 figs. 3 to 6), the thorax and the abdomen are connected 

 by a small point of attachment, or sometimes by a longer 

 or shorter stalk. 



It may be also observed here that no large-waisted 



* The perfect insects in Terebrantia feed chiefly or entirely on vegetable 

 matter, as honey, pollen, juice of fruit, &c. In some cases they take little 

 or no food. 



t The actually gall-making insects are not entomophagous, the larvae 

 feeding on the vegetable matter of the gall, but the gall-making species 

 are so closely connected with parasitic species that it has been found in- 

 convenient or impossible to separate them. They are therefore included 

 under the head Entomophaga. 



