62 



Spreading boards may be made much smaller or much larger 

 to suit moths of different sizes; the space between the top boards 

 must always be large enough to admit the body of the insect. 

 To use the spreading board : insert the pin with the butterfly 

 on it into the linoleum just far enough so that the body of 

 insect will be in the space between the boards up to the win'gs, 

 Fig. 8. Place the wings out flat on the board and fasten them 

 there with narrow strips of paper pinned across them, Fig. 7^^ a. 

 While held down by these strips of paper arrange them so that 

 the hind margins of the front wings shall cover the front 

 margins of the hind wings and shall be in a line at right angles 

 to the body ; then pin larger pieces of paper over the rest of 

 the wings, Fig. 7, b. Sometimes isinglass is used instead of 

 paper to hold the wings down, Fig. 7, c. The insects should 

 be left on the spreading board at least three days ; and when 

 the board has insects on it, it should be kept in a box where 

 the museum pests and mice cannot get at it. 



Sometimes when the moths are not spread soon after being 

 killed they become so stiff that the wings cannot be moved 

 without breaking them. In such cases the insects should be 

 put on some paper in a jar which has some wet sand in the 



bottom and which can be covered 

 tightly. The air in such a can is so 

 moist that in two or three days the 

 insect will become limber and may 

 be spread with ease. 



AN AQUARIUM. FIG. 9. 



An aquarium with living, moving 

 insects in it is a very interesting orna- 

 ment for the window-sill of a school- 

 room. A glass candy jar or even a 

 butter jar may be transformed into 

 such an aquarium thus : first, put irtto 

 the jar a layer of sand about two 

 inches deep ; in this sand plant some 

 small water weeds and then add a layer 

 of gravel or pebbles ; then nearly fill 

 the jar with rain water, pouring it in 

 carefully so as not to disturb the plants. 



Fig. 9. An aquaruim. 



