2.30 PROCEEDINGS OP THE AMERICAN ACADEMY 



ice prevail, do uot form, concerning the color of insects, a counterpart 

 to the trojjics to the extent we might expect. Of course we find 

 there white or pale-colored species, but they are by no means numer- 

 ous, and the so-called winter insects, which are found on the snow, 

 are mostly dark brown or black. But even in the coldest regions 

 beautiful and gayly colored species occur, but mostly yellow, orange, 

 or red ones. 



An interesting and only recently studied fact, is the change of 

 colors of the same insect in different countries. Some valuable hints 

 are given by Dr. Speyer (Stettin, entom. Zeit. 1875, p. 103). If the 

 predominant colors of Noctuidas are gray, brown, or reddish brown, or 

 rather a mixture of black, white, and red, less red and more black 

 has been observed in North American specimens, and less black and 

 more red in European ones of the same species. If the colors are a 

 mixture of yellow and red, just the op2:)Osite change is seen ; in the 

 North American specimens the red is predominant, in the European 

 ones the yellow. 



A few words more about beautifliUy colored caterpillars. As 

 sexual selection could uot have acted here, and as it was observed 

 that some of them were not taken by certain species of birds and 

 lizards, but purposely avoided by them, it was supposed that the 

 splendid color serves here as protection. But if we remember that 

 some birds prefer certain caterpillars, and other birds others, as, for 

 instance, the hairy caterpillars, whose hairy cover suggests the idea of 

 protection, we shall arrive at the conclusion that more observations are 

 needed to confirm the above-quoted supposition. 



Water insects are nearly all of the same dark hue, yellowish brown 

 to black, often with an olive shade. Only parts of the body which 

 are uncovered in the air (abdomen of Nepa) are sometimes of a 

 brighter purple color. But even among water insects some are to be 

 found (Hydrachna) of an intense red color. 



The climax of the development of the pure and elementary colors 

 seems to be reached in the class of insects. All these colors appear 

 here without any transition whatsoever, even in close juxtaposition. 



77ie Pattern. 



The pattern of the colors of insects is a subject very important for 

 every naturalist who studies or describes insects. Till to-day only 

 very little has been published about the pattern. Something is stated 



