HYMENOPTERA. 149 



nished with a borer, or ovipositor, but of a different cha- 

 racter by its assistance the little Cynips bores the leaves 

 or tender shoots of trees, in which she lays her eggs the 

 wounded part, strangely responsive to such a stimulus, 

 swells out into an excrescence that is called a gall. The 



FlG. 10t. GALL FLY. 



form and the solidity of these vegetable productions varies 

 according to the part of the plant which produces it. The 

 leaves, the buds, the petioles, the bark, the roots, all form 

 their different kinds, some of which are useful in the arts. 

 The gall-nut of the oak, for instance, yields a deep black 

 dye, and is employed in making ink. The larvae hatched 

 within these galls find there both board and lodging, till 

 the time arrives for their last change. 



In the second section of the Hymenopterous In- 

 sects, the females, instead of an ovipositor, are 

 furnished with a sting. This section embraces 



The Ants (Formica), so celebrated for their foresight 

 and their industry. These insects live in societies that 

 are often very numerous, and consist of individuals of three 

 different denominations the males, the females, and the 



