ICHNEUMON lAYING EGGS. 133 



the larvse her agitation quickened to the utmost 

 intensity ; she soon bent her body in a slanting 

 direction beneath her breast, appUed her tail 

 to the larvae, and, becoming still as death, sent 

 forth her curious sheath and deposited her egg 

 in the victim, which writhed considerably under 

 the operation. If she came to one that had 

 pre\dously an egg in it, she left it in an instant 

 and sought another ; for the platj^gaster lays but 

 one in each. This however, often repeated, 

 destroys a great many of these little devasta- 

 tors of the grain. The observations of professor 

 Henslow confirm those which have been already 

 made. He says, "When these eggs are hatched, 

 the young maggots which they produce, and 

 which are the caterpillars of the ichneumons, 

 feed upon the fleshy or muscular parts of the 

 caterpillar they are attacking, carefully avoiding 

 the vital parts. At length the caterpillar, they 

 have been thus devouring alive, dies ; or, as 

 frequently happens, it changes to the state of 

 a chrysalis before it is destroyed. The ich- 

 neumon caterpillars also pass to the chrysalis 

 state, and either remain within the body of the 

 dead caterpillar, or come out before they assume 

 the fly state. Each species of ichneumon is 

 restricted in its attacks to one, or at most to a 



