ADJUSTMENT OF ORGANISMS TO ENVIRONMENT 431 



stinging hymenoptera, bees and wasps ; a few have mimicked 

 ants which are distasteful by reason of the formic acid they 

 secrete ; a few have mimicked unpalatable species in other 

 groups, the best known of which is probably the viceroy 

 butterfly which mimicks the monarch. There are some 

 examples of coloration phenomena so fit, so admirable in 

 every specific detail, of color form and posture, and so well 



FIG. 254. Mimicry, a. a robber fly (Dasyllis grossa) 

 which mimicks the bumblebee b (Bombus). 



adapted to the purpose they seem to serve in nature, that 

 they excite our instant admiration. But of the animals one 

 may gather in an hour's collecting, many will show less fit- 

 ness, and some will have a coloration that appears to be 

 without adaptive significance. Coloration existed before it 

 became adaptive. There is danger of finding here, as in the 

 case of the coloration of flowers (Chap, i) adaptive signifi- 



