COLOR AND PATTERN IN ANIMALS 



401 



FIG. 248. Katydid, Cyrtophyllis crepitans, from the West 

 Indies, with green body and wings resembling the leaves 

 among which it lives. (After Sharp.) 



The green katydid singing in the tree-top or shrubbery is 

 readily known to be there by its music, but just which bit of 

 green that we see is katydid, and which is leaf, is a matter to 

 be decided only by unusually discriminating eyes. The clacking 

 locust, beating its 

 black wings in the 

 air, is conspicuous 

 enough; but after 

 it has alighted on 

 the ground it is 

 invisible, or, 

 rather, visible but 

 indistinguishable : 

 its gray and brown 

 mottled color pat- 

 tern is simply continuous with that of the soil. The green 

 larvae of the Pierid butterflies lying longitudinally along green 

 grasses simply merge into the color scheme of their environ- 

 ment. The gray moths rest unperceived on the bark of the 



tree trunk. Hosts of insect kinds 

 do really harmonize with the color 

 of their usual environ- 

 and by this correspondence 

 in shade and marking, are difficult 

 to perceive for what they are. 

 Now if the eyes that survey the 

 green foliage or run over the gray 

 bark are those of a preying bird, 

 lizard, or other enemy, it is quite 

 certain our reason tells us so in- 

 sistently that this possession by 

 the insect of color and pattern 

 tending to make it indistinguish- 

 able from its immediate environ- 

 FIG. 249.-Smaii locust of the Colo- ment is advantageous to it ad- 



rado-Mohave desert on the sand. vantagCOUS to the degree often of 



saving its life. Now such a use 



of color and pattern is obviously one which can be widespread 

 through the insect class, and may be, to many species which 

 lead lives exposed to the attacks of insectivorous animals, of 

 large even of life and death importance. And naturalists, 



