CHAPTER XI 

 Hymenoptera : the Ants, Bees, Wasps, and Sawflies 



The ants, bees, wasps, and sawflies, with other related in- 

 sects, form one of the most characteristic of all the orders. 

 It is called Hymenoptera, and its members may be known by 

 the fact that they pass through complete transformations, 

 and that the adults generally have four more or less trans- 

 parent membranous wings, of which the front pair is the 

 larger. The mouth parts are formed for biting, but there 

 is commonly present also a tongue by means of which the 

 insects can suck or lap up liquids. In the case of the 

 higher members of this order, the larvae feed upon a special 

 food prepared by the adults. 



Sawflies 



As very few of the Hymenoptera feed on plant tissues, 

 a comparatively limited number of injurious species are 

 found in the order. Of these the most im- 

 portant belong to the great family of Sawflies 

 (Tenthredinidse) which are characterized by 

 having an ovipositor by means of which the 

 insects are able to cut holes in vegetable tis- Cherry saw- 



. . ... _, FLY Magnified 



sues for the msertion of their eggs. The 

 eggs are commonly laid within such cavities, but sometimes 

 they are deposited along the outer surface of leaf or stem. 

 They soon hatch into caterpillar-like larvae, commonly 

 called false caterpillars or slugs, which feed upon the foli- 

 age and finally spin cocoons within which they change to 



149 



