42 



BULLETIN 67, UNITED STATES NATIONAL MUSEUM. 



also not so small as to break or bend too easily, are cut from a con- 

 venient bush. The sticks are placed crosswise over the cloth and 

 fastened to the loops at the four ends. This is easily and quickly 

 done by making sliding loops of the simple loops. The cloth is thus 

 kept spread out between the sticks. To the center of the sticks 

 another stick may be fastened, so as to hold the cloth out under the 

 branch. 



The sieve. — This consists of a wire sieve, to which is secured a cylin- 

 drical bag or net (fig. 85). Masses of fallen leaves may be taken up 



and dumped into the 

 bag, and when shaken 

 the insects will fall 

 through upon a white 

 cloth or stiff paper 

 placed on the ground 

 for this purpose. A 

 good size for the sieve 

 is a foot in diameter. 

 The meshes should 

 not be over one- 

 fourth inch, and for 

 sifting some mate- 

 rials one-eighth inch. 

 In using the sieve 

 one must not shake 

 it too long before ex- 

 amining the cloth, 

 else there will be so 

 much debris as to 

 obscure the insects. 

 Many insects, when 

 disturbed in this 

 way, will play " pos- 

 sum," and it is therefore necesary to leave the cloth a few 

 moments to give these coy insects a chance to start in motion. 

 Two cloths laid a few feet apart and used alternately will effect this 

 purpose. In cold weather one may so place and incline the cloth or 

 paper that the sun will strike and warm the dormant insects into 

 activity. 



Besides dead leaves, the sieve may be used to get the insect forms 

 from moss, ants' nests, old decayed trees, etc. One will be surprised 

 at the great number of forms that may be gathered by the judicious 

 use of the sieve. Many larva? may be found, and a vial with a 

 toothpick wet with glycerin will be handy to pick up the minute 

 springtails and other forms. In winter one may gather likely material 



Fig. 84.- 



-The umbrella and its mode of use. 



WETTER.) 



(After Kiesen- 



