. Bulletin - United States National Museum. Science. 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
. Bulletin - United States National Museum. Science. 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. -The umbrella and its mode of use. WETTER.) (After Kiesen-. Please note that these images are extra
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