162 ICHNEUMON FLY. 



of the leaves, and are so disagreeably tenacious of 

 their rights of possession. Pest as it is to the 

 gardeners, to cooks, and sometimes, alas ! to con- 

 sumers, it would be a hundredfold worse but for the 

 exertions of a fly so small as hardly to be noticed, 

 but by its effects. This insect belongs to the same 

 order as the bees, and is shown upon plate J, fig. 6. 

 Small though it be, one such insect can compass 

 the destruction of many a caterpillar, though not 

 one thousandth part of the size of a single victim. 

 "While the caterpillar is feeding, the ichneumon fly, 

 as it is called, settles upon its back, pierces its skin 

 with a little drill, wherewith it is furnished, and in 

 the wound deposits an egg. This process is repeated 

 until the ichneumon's work is done. 



As eaeh wound is made, the caterpillar seems to 

 wince, but shows no farther sense of uneasiness, and 

 proceeds with its eating as usual. But its food serves 

 very little for its own nourishment, because the 

 ichneumon's eggs are speedily hatched into ichneu- 

 mon grubs, and consume the fatty portions of the 

 caterpillar as fast as it is formed. 



In process of time the caterpillar ought to take the 

 chrysalis shape, and for that purpose leaves its food 

 and seeks a convenient spot for its change. 



That change never comes, for the ichneumons 

 have been growing as fast as the caterpillar, with 

 whose development they keep pace. And no sooner 

 has their victim ceased to feed, than they simulta- 



