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NEBRASKA STATE HORTICULTURAL SOCIETY 



parasites are ready to emerge, which is usually long after the cater- 

 pillar is dead, they cut a neat round holde in the top of the cocoon -avaI 

 escape as full grown insects. Those which remain inside the host to 

 pupate behave in a very different manner. When they are full grown 

 they do not come through the skin as do the others, but line up side by 

 side, with their heads all pointing toward the back of the caterpillar. 

 When their cocoons are spun they make two, three, or four rows the 

 length of the caterpillar. When the insects emerge, each one cuts a 

 round hole in the dried skin of the back of the now dead caterpillar, 

 making a regular pepper-box appearance. 



Acronycta larva killed by 'a braconid, 

 Rhngas intermedius. [After Bruner. ] 



The next group to be considered is composed of very small or minute 

 insects which are called Chalcididae. They may be known by their 

 peculiar jumping habit, their antennae which have a distinct elbow joint, 

 an their hind legs which usually, though not always, are considerably 

 thickened. There is nothing striking in their method of attacking their 

 hosts since they develop and pupate within the body of the caterpillar 

 without spinning any cocoons. These last two groups contain the large 

 majority of the most important parasites and are of immense value from 

 the economical standpoint. 



A Chalcid ( Chalcis mariae) 

 [After Riley.] 



This completes the list of twc-winged and four-winged parasites 

 which attack other insects in their pupal or growing stage. During the 

 resting stage, however, insects are also preyed upon by certain enemies 

 though not to so great an extent. All of these parasites are Chalcids with 

 the possible exception of a few of the Ichneumons. Since both of these 



