MIMICRY 1599 



their external appearance, to the features and colors 

 of the regions which they inhabit, must strike every 

 traveler with astonishment. 



"At a small distance the hartbeest (antelope), 

 when stationary, is really not distinguishable from 

 red ant-heaps which everywhere abound; the long- 

 legged and long-necked giraffe can not be distin- 

 guished from the dead trunk of a mimosa, the zebra 

 from a gray-brown clump of grass and thorn-scrub, 

 the rhinoceros from a fallen trunk of a tree. It is 

 only when they move that they can be distinguished. 

 Nature has also extended this protective mimicry 

 (Schutzspiel) to the small insects; and perhaps for 

 this reason they often escape the eye specially in 

 search of them; for butterflies and grasshoppers look 

 like dry twigs, the cicadae like leaf-stalks, the spiders 

 like thorns, the phasmodae like bare twigs, beetles 

 like small lumps of earth and small stones, moths like 

 mosses and lichens. 



"This protective mimicry is manifested not only 

 in regard to the colors and forms of the animals, 

 but also as regards their movements, or their man- 

 ner of standing still, and in their preference for cer- 

 tain localities appropriate to their disguise. There 

 is protection everywhere; protection against climatic 

 extremes and against animal foes; such varied and 

 abundant protection as could only be developed by 

 natural selection in a primeval continent like Africa." 



In spite of the voluminous literature of "animal 

 mimicry" since Bates first published his classical 

 memoir on the subject, the exact nature of the process 

 whereby insects and other creatures "mimic" 



