30 



The following table shows the dates at which the lice have been 

 observed. It is deficient in not showing the relative abundance at 

 the different dates of the stages, larva, pupa, and adult females : 



The species will probably be found to occur in every county of the 

 State. We have observed it or had it reported from the following : 

 Stephenson, Ogle, DeKalb, Eock Island, Kendall, LaSalle, Putnam, 

 Stark, Livingston, Warren, Peoria, McLean, Tazewell, Mason, Me- 

 nard, Champaign, Morgan, Jersey, Fayette, Ef&ngham, Marion, 

 White, Madison, Union, and Pulaski. 



PAKASITES AND PREDACEOUS INSECTS AFFECTING THE CORN LOUSE. 



A most efficient check on the further increase of the corn louse 

 exists in a small four-winged ffy, belonging to the genus Adialytus, 

 which deposits its eggs within the bodies of the lice and in its 

 larva state feeds upon their tissues. The greater part of a colony 

 of the lice is sometimes thus infested, the lice containing the grubs 

 which hatch from the eggs being kno^vn by their brown swollen 

 bodies, or at an earlier stage by a slightly yellowish color. The 

 adult Adialytus is a slender, active ichneumon ffy, about .06 inch 

 in length. Its feelers and legs are long and slender and the abdo- 

 men is very flexible so that it can easily be bent upon itself. The 



