CH. vii DEFENCES OF INSECTS 243 



and colour Mimetic analogies among beetles Hymen- 

 optera mimicked by Lepidoptera, Diptera, Coleoptera, 

 Orthoptera, Hemiptera Mimicry of Coleoptera Of ants 

 by spiders Of vertebrates Predacious insects that re- 

 semble their prey, or a form to which their prey is in- 

 different The great frequency of Mimicry in insects. 



Apart from the insects considered in the last chapter, 

 in whose lives the principles of disguise and conceal- 

 ment constitute so important a feature, the most 

 casual observer of Nature must be struck by the 

 existence of a group in whom the development of 

 brilliant colour and conspicuousness is as marked as 

 are the suppression and absence of these properties in 

 the previous cases. The latter court observation 

 and proclaim their presence ; to elude notice every 

 imaginable contrivance seems as it were to be exerted 

 by the former class. In face of the remarkable 

 utility of the assumption of obscure or imitative tints 

 by all animals, and the readiness of the acquisition 

 of means of concealment through the agency of 

 natural selection, it would appear that there ought 

 to be no conspicuous and brilliantly coloured insects. 



Where Protective Resemblance is wanting, the idea 

 instantly suggests itself that protection must be 

 gained in some other way. Observation of the life of 

 insects soon shows that, far from being confined to 

 one mode of maintaining their existence, they are in 

 fact possessed of a variety of means by which to 

 defend themselves from enemies and to obtain their 

 food. 



All are not equally palatable to insect-eating 

 animals. Experiment places it beyond doubt 



R 2 



