122 ZOOLOGY. 



fishes (spines), and some snakes; also in the repulsive odors 

 of the skunk and many caterpillars. Caterpillars oftentimes 

 have an acrid or otherwise unpleasant taste, but, unless this is 

 associated with a special odor or color by which its enemies 

 may recognize the fact, it is not likely to prove of any great 

 service to the animal possessing it since a single incision in 

 the soft body made by the bill of a bird is likely to cause death. 

 For similar reasons animals with stings are often highly 

 colored. The colors or other marks are, in these cases, in the 

 nature of warnings. The " monarch," one of our large con- 

 spicuous butterflies is an illustration of the association of color 

 and offensive taste ; the wasps and the coral-snake, of the asso- 

 ciation of color with the possession of stinging powers. Thus 

 owing to the power of association in the mind of the enemies, 

 the advantage comes to lie quite as much in the possession of 

 the special color or form as in the presence of the underlying 

 protective powers. These facts give rise to the remarkable 

 phenomena of mimicry. This term applies to those instances 

 where an edible or harmless animal, by reason of its similarity 

 to those which are disagreeable, partakes of their immunity 

 from attack. Mimicry must not be considered as in any way 

 a matter of choice with the animal but simply the result of 

 natural selection in preserving and allowing the propagation 

 of favorable variations. The viceroy butterfly, though edible, 

 seems to be protected by its striking likeness to the monarch. 

 The nearest relatives of the viceroy are quite differently 

 marked. Mimicry of bees and wasps is found among many 

 flies and some moths and beetles. Non-venomous snakes occa- 

 sionally have the marking and the motions of venomous. 



160. Practical Exercise. Try to discover instances of general pro- 

 tective resemblance among the animals known to you. Analyze each case 

 and see just the nature and value of the projection. Treat similarly the 

 subject of special protective resemblance. Do you know any really harm- 

 less animals which assume apparently dangerous attitudes for protection? 

 Accumulate all the available references on mimicry. What range of color 

 have you seen illustrated among animals? In a single animal? Where, 

 on the earth, are the brightest-hued animals found? What are believed to 



