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POPULAR SCIENCE MONTHLY. 



well as of the rest of the exposed portions of the body, are such as to 

 assimilate closely with the bark of the tree upon which the insect 

 rests. In such a situation it requires a sharp eye to detect the pres- 

 ence of the moth, which, unless disturbed, flies only at night, re- 

 maining all day exposed to the attacks of many enemies. Probably 



Carolina Locust at Kest. 



the most important of these are the birds, especially species like the 

 woodpeckers, which are constantly exploring all portions of the 

 trunks of trees. 



The chief beauty of these Catocalas as they are seen spread out 

 in the museum cabinet lies in the fact that the hind wings, which, 

 when the moth is at rest in life, are concealed by the front ones, 

 are brightly colored in contrasting hues of black, red, and white in 

 various brilliant combinations. These colors, in connection with the 

 soft and blended tones of the front wings, make a very handsome 

 insect. 



To explain these colors many suggestions have been made. The 

 protective hues of the upper wings are easy to account for by ac- 

 cepted biological theories, but the bright colors of the under wings 

 have presented more difficulties. Some biologists have supposed that 

 the latter were without special significance, being produced by the 

 tendencies of the insect to bright colors — the tendency not being 

 kept down by the eliminating factors which would operate in the 

 case of exposed portions of the body. On this principle Mr. Bed- 

 dard would " expect that bright coloration would be the rule rather 

 than the exception among nocturnal insects, for, however bright and 

 varied, the colors would be invisible at night and could do their pos- 



