40 GKAMMAB OF ENTOMOLOGY. 



CHAPTER VII. 



HISTORY OF THE ICHNEUMON. 



Class Hymenoptera. I Genus Pimpla. 



Order Ichneumonites. I Species Instigator. 



120. There are many butterflies and moths 

 which increase so rapidly, tliat, without a check, 

 their caterpillars would, in two or three years at 

 the utmost, devour every green leaf on the face 

 of the earth, and render it incapable of supporting 

 its present inhabitants. 



121. The ichneumons are evidently created to 

 act as a check to this devastation : they are gene- 

 rally small insects, with slender bodies, and have 

 four transparent wings : they are very active, 

 running about the stems and leaves of plants in 

 search of caterpillars, and fly very readily. 



122. The ichneumons are of many kinds: 

 more than a thousand varieties have been described 

 by naturalists ; and it is supposed that every 

 butterfly, and every moth, indeed, almost every 

 insect, has one peculiar to itself: the history 

 of them all is nearly similar, 



