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THE ICHNEUMON TRIBE*. 



ALL the Ichneumons are parasitical - } their larvas 

 deriving support 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 or 

 caterpillar, 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 

 it no sooner discovers one of those nests than it 

 fixes on it, and in a moment bores through the 

 mortar of which it is built. 



Some species agglutinate their eggs upon cater- 

 pillars ; others penetrate their bodies, and deposit 

 the eggs in their inside. When the larv*c are 

 hatched, the head is so situated that they pierce 

 the caterpillars, and penetrate to their very entrails. 

 These larvas suck the nutritious juices of the crea- 

 tures without attacking their vitals; for they seem 

 to be all the time perfectly healthy, and even some- 

 times are enabled to transform themselves into chry- 

 •salids. " A friend of mine," says Dr. Derham, 

 " put about forty large caterpillars, collected from 

 cabbages, on some bran and a few leaves, into a 

 box, and covered it with gauze to prevent escape 



* The Linnean order of Hymen opterovs Insects commences 

 here. 



vol. in. A a 



