12 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 39 



to another bottle. If the type of bottle shown in fig. 5 is used, it 

 is necessary only to exchange corks. 



Sifter 



Perhaps no special collecting method nets more interesting, 

 rare, and diverse kinds of insects than that involved in sifting 

 rotten logs, leaf mold, and other forest and prairie ground cover. 



Fig. 6. — Sifter, showing hand grips. Sift debris containing insects over a 

 piece of white oilcloth. Do not fill the sifter more than half full. When you 

 put in a sample, sift it gently at first and then violently. Finally, empty the 

 contents of the sifter on the oilcloth to capture specimens too large to go 

 through the mesh. Patience is required to get the best results with the sifter, 

 which provides one of the best methods for winter collecting. 



To do this type of collecting, provide yourself with the following : 



1. A stout sifting sieve about 12 by 12 inches and 4 to 6 

 inches deep, fig. 6. The bottom may be wire screen of any desired 

 mesh ; usually 8, 10, or 12 meshes to the inch give good general 

 results. 



2. A sturdy piece of white oilcloth about 18 inches or 2 feet 

 square. 



3. Collecting equipment, including an aspirator. 

 Material such as leaf mold is placed in the sieve and this is 



shaken over the white oilcloth, which has been spread on a level 

 spot on the ground. The small insects fall on the cloth and can 

 be picked up with the aspirator or with a camel's-hair brush. 



