2 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 39 



In early spring, when insects can be taken only sparingly in 

 the open, the collector frequently finds sheltered hollows where 

 they may be caught in large numbers. Many kinds of insects live 

 only on a certain plant, and to obtain them the collector must 

 search or sweep the host plant that the insect prefers. 



Many obscure places harbor insects seldom found elsewhere. 

 Among these are leaf mold and debris on the surface of the soil, 

 particularly in woods ; rotten logs and stumps, which should first 

 be turned over for insects that hide under or around them, and 

 then carefully searched or torn apart for others that live inside ; 

 in, under, and around dead animals ; under boards and stones. 



Trees sometimes yield valuable specimens. If part of a tree, 

 under which has been spread a large white sheet, is struck with 

 a heavy padded stick, many insects in the branches, such as 

 weevils, will fall to the sheet and "play possum." They can be 

 picked off quite easily. 



Lights attract large numbers of certain nocturnal insects 

 such as June beetles and many kinds of moths ; at night these in- 

 sects may be collected at street or porch lights, on windows and 

 screens of lighted rooms, or at light traps put up especially to 

 attract them. Swarms of aquatic insects come to street lights 

 of towns along rivers, sometimes in such numbers as to pile up in 

 a crawling mass under each light. Collecting at this source is best 

 on warm cloudy nights ; wind or cold keeps most nocturnal insects 

 fairly inactive. Different species of moths and beetles visit the 

 lights in different seasons so that collecting of this type alone 

 yields many kinds of insects. 



Insects that live in the water may be collected by the use of 

 heavy dip nets, swept through the water at various levels and 

 through the mud and debris at the bottom. In shallow water, 

 many insects will be found if stones and logs are turned over and 

 leaf tufts pulled apart. 



In winter, insect galls or cocoons may be gathered. If these 

 are placed in jars with a cheesecloth cover tied over them, kept 

 in a warm room, but away from radiators and all intense heat, 

 many insects will emerge from them before spring. 



WHAT TO USE 



For making even a fairly large insect collection only a small 

 amount of equipment is required. A net and killing bottle are 

 essential, and good work may be done with these alone. A greater 



