74 MIMICRY, AND OTHER PROTECTIVE 



and polished coat of mail which may render them 

 unsatisfactory food to such birds as would be able to 

 capture them. The causes which lead to the develop- 

 ment of colour have been here able to act unchecked, 

 and we see the result in a large variety of the most 

 gorgeously-coloured insects. 



Here, then, with our very imperfect knowledge of 

 the life-history of animals, we are able to see that 

 there are widely varied modes by which they may 

 obtain protection from their enemies or concealment 

 from their prey. Some of these seem to be so com- 

 plete and effectual as to answer all the wants of the 

 race, and lead to the maintenance of the largest pos- 

 sible population. When this is the case, we can well 

 understand that no further protection derived from a 

 modification of colour can be of the slightest use, and 

 the most brilliant hues may be developed without any 

 prejudicial effect upon the species. On some of the 

 laws that determine the development of colour some- 

 thing may be said presently. It is now merely neces- 

 sary to show that concealment by obscure or imitative 

 tints is only one out of very many ways by which 

 animals maintain their existence ; and having done 

 this we are prepared to consider the phenomena of 

 what has been termed " mimicry." It is to be par- 

 ticularly observed, however, that the word is not here 

 used in the sense of voluntary imitation, but to imply 

 a particular kind of resemblance a resemblance not in 

 internal structure but in external appearance a resem- 

 blance in those parts only that catch the eye a re- 



