THE ICHNEUMON FLIES. Tlj 



the lower ones shorter than the others. The sting is composed of two 

 serrated laminae, and is almost concealed in the body. 



This insect is small, of a yellowish tinge, and, in its general 

 appearance, is not much unlike a common house-fly. 



By means of the saw with which these insects are supplied, some 

 of the species deposit their eggs in the buds of flowers, and others in 

 the twigs of trees or shrubs. This implement, which is situated in the 

 posterior part of their body, is formidable only in appearance, and 

 seems destined solely to the purpose of depositing their eggs. 



The larvae have from eighteen to twenty-eight legs. They subsist 

 on the leaves of plants; and, when full grown, some of them bury 

 themselves in the ground, and others form a nidus between the leaves 

 of the plant on which they feed, and within it change to a pupa. 

 Those which undergo their change under the earth, usually remain 

 there during the winter, the perfect insect issuino^ forth in the ensuing 

 spring. 



OF THE ICHNEUMONS. 



THE ICHXEUUOM FIT. 



THE OADFLT. 



The antennae of the Ichneumon-flies taper towards their extremity 

 and consist of 

 more than thirty 

 joints or articu- 

 1 a t i o n s . The 

 mouth is armed 

 with jaws, and 

 has four unequal 

 thread-sha ped 

 feelers. At the 

 extremity of the 

 abdomen there is 

 a long sting, 



having, however, no pungent property, enclosed in a cylindrical sheatb 

 composed of two valves. 



The larvas of all the Ichneumons derive nutriment from other 

 insects. The female, when about to lay her eggs, perforates with her 

 sting either the body or the nidus of some other insect oi \.-aterpillar, 

 and deposits them there. The sting of one of the species, though 

 extremely fine, is so strong as to penetrate through mortar and plaster. 

 The food of the family to be produced from the eggs of this fly, is the 

 larvae of wasps or mason-bees ; for the parent Ichneumon no sooner 

 discovers one of the nests of these insects, than it fixes on it and in a 

 moment bores through the mortar, of which it is built. 



Some species agglutinate their eggs upon caterpillars; others pene- 

 trate the bodies of caterpillars, and deposit their eggs in the inside. 

 When the larvcB are hatched, their heads are so situated that they 

 pierce the caterpillars, and penetrate to their very entrails. These 

 larvae suck the nutritious juices of the creatures without attacking 

 their vitals; for they seem to be all the time perfectly healthy, and 

 33 



