18 AMERICAN MUSEUM GUIDE LEAFLETS 



acid added to the water will prevent mold. Twenty-four hours 

 will usually be sufficient to relax even the driest, but more time may 

 sometimes be necessary. If the insect has neither scales nor hairs, 

 it can be quickly relaxed by immersing it in warm water. 



It will be noticed that both the setting boards illustrated here 

 give the wings a slight upward tilt. If they keep this position it will 

 not be objectionable, but they are not likely to do so, since the 

 weight of the wings will probably drop them to the horizontal at least. 

 Large insects dry more slowly than small ones and it will prob- 

 ably be necessary to allow them to remain on the boards for 

 about two weeks. They should certainly remain until thoroughly 

 dried. No further presentation is then necessar>^, as a rule, for the 

 fairly hard-bodied adult insects. Some tropical grasshoppers have 

 large abdomens full of fat and decomposing food. These should first 

 be opened by an incision along the belly, the viscera taken out, and 

 the abdomen stuffed w^ith cotton. Broken specimens may be repaired 

 with shellac or tliin glue. 



Caterpillars may be prepared in the following way: Make a cir- 

 cular incision at the hind end, cutting the intestine loose from the 

 outer body wall. Then, laying the caterpillar on a piece of clean blot- 

 ting paper, squeeze the viscera through this opening by gently 

 rolHng the caterpillar with a lead pencil, beginning near the hind 

 end and gradually w^orking toward the front. After the viscera have 

 been gotten rid of, for the most part, insert a straw and fasten the 

 first segment of the larva to the end of the straw by means of a fine 

 needle. Draw the hind segment up the straw until the larva is natural 

 length and fasten it in the same manner. Then inflate the 

 larva by gentl}^ blowing through the straw\ Since the front end of 

 the straw may get plugged up it is well to make a small hole in the 

 side of the straw before it is inserted. This hole had best come about 

 midway between the larva's head and tail. Since inflation must be 

 kept up until the larva's skin is dried, gentle heat is ordinarily used. 

 A tin can with holes punched in it for ventilation and heated by an 

 alcohol lamp makes a good oven, or one made for the purpose can 

 be purchased. Dealers also sell bellows, tubing, clips, etc., to make 

 the work of inflating easier. However inflated, green larvae are apt 

 to lose their color, for it is chlorophyll which fades rapidly. Slow 

 drj'ing paints relax the skin and distort it. Therefore, if painting is 

 done, the pigments should be mixed with benzine or the Hke. 



