SAW-FLIES. 103 



ORDER HYMENOPTERA. 



Wings four, with few veins ; apparently naked, but frequently 

 clothed with short scattered bristles ; mouth furnished with man- 

 dibles, and likewise with a proboscis ; female with a conspicuous 

 ovipositor, often modified into a sting ; larvse generally footless ; 

 pupae inactive. 



The Order Hymenoptera is one of the most intei-esting and 

 extensive. The habits and structure of the insects which it 

 includes are very various. Among these are the Ants, Bees, and 

 Wasps, which live in communities, and exhibit an amount of in- 

 telligence far exceeding that of any other insects, except, perhaps, 

 the Termites, which they also resemble in the work of the com- 

 munity being executed by imperfectly-developed females, called 

 workers, which are sometimes of two or three kinds, Avith special 

 duties, and which form the bulk of the population. The great 

 bulk of parasitic insects likewise belong to the present Order. 

 Linne called this Order Hymenoptera in allusion to the row of 

 small hooks connecting the front and hind wings during flight; 

 however, many species are included in it which are apterous in 

 one or both sexes. It is primarily divided into Hymenoptera Tere- 

 brantia, in which the ovipositor is used as a borer, and the 

 Hymejiojytera Aculeata, in which it is modified into a sting. In the 

 latter section, the antennae are thirteen-jointed in the males, and 

 twelve-jointed in the females. 



I. — Hymenoptera Terebrantia — Phytophaga. 



Abdomen not stalked ; larva with from six to twenty-two legs, 

 feeding on plants or trees. 



Fajmily I. — Tenthredinidce. 



Ovipositor of the female modified into a saw, and used to 

 form incisions on leaves for the reception of her eggs ; larvse 

 resembling caterpillars, and feeding exposed on plants. 



