164 



ICHNEUMONID.E, OR ICHNEUMONS. 



pupae, still preferring the larvas when they can meet with them. 

 The young Ichneumons, when hatched as footless grubs, some- 

 times in considerable numbers in the body of one caterpillar, 

 devour only the fatty parts, which are not absolutely essential 

 to life ; and the animal they infest may continue to exist for 

 some time, thus affording them a continued supply of nutriment ; 

 but when the Ichneumons are ready to undergo their last meta- 

 morphosis, they either pierce the skin and escape, or else they 

 kill their victim, and perform their changes within its body. 

 The perfect Ichneumons feed solely upon the juices of flowers, 

 and fly about with considerable agility in search of their nutri- 

 ment, or of proper situations for the deposition of their eggs. 

 It is in the genus Pimpla, that the ovipositor attains its greatest 



development, its 

 length being in 

 some exotic spe- 

 cies as much as 

 three or four 

 inches ; when 

 not in use, it is 

 inclosed in two 

 long channelled 

 filaments, which 

 unite to receive 

 it like a sheath. 

 This family is 

 extremely nu- 

 merous. Proba- 

 bly more than 



3000 species exist in Europe alone ; and the number peculiar to 

 other parts of the globe may fairly be reckoned as at least equal. 

 Scarcely any tribe of Insects is free from their attacks ; although, 

 as already stated, the Lepidoptera are the chief sufferers. In 

 restraining the multiplication of many Insects, which commit 

 great injury against the Agriculturist, the Ichneumonidae render 

 essential service to Man ; and there is no mode in which they 

 can be said to do him any counteracting injury. 



FlG. 385. PlMPLA MANIFESTATOR, DEPOSITING ITS EGGS. 



