248 ROMANCE OF THE INSECT WORLD CHAP. 



seized and tasted, and though it was, afterwards 

 rejected in all probability the wounds would prove 

 ultimately fatal. Thus by natural selection have 

 the bright colouration and the distasteful qualities 

 become associated. The association is one easily 

 learned and remembered by enemies, and saves a 

 continual destruction of individuals. The immensity 

 of the benefit derived by the conspicuous species is 

 realised when it is considered how small is the 

 comparative loss of life involved in the education of 

 the enemy. 



Let it not be supposed that these varied means of 

 protection are necessarily attended by Warning 

 Colours. Nature is open to too many influences to 

 be able to develop on any such rigid hard and fast 

 plan. Here we find one set of defences in combina- 

 tion, there another. The gregarious habit of some 

 inedible dull-coloured caterpillars is of itself a 

 " warning," for their offensive odour gives timely 

 notice to an approaching enemy, so that the acquisi- 

 tion of bright colour can be dispensed with. Again 

 the great family of ground-beetles (Carabidse) are 

 almost all of disagreeable smell, but they do not 

 present very vivid hues, probably because they are 

 mostly nocturnal and predacious, and it is important 

 that they should be sufficiently invisible at night to 

 creep unseen upon their prey. By day their odour 

 and taste keep foes at a distance, while the metallic 

 tints adorning them, when they arc not wholly black, 

 are fairly conspicuous. It must be remembered that 

 the acquisition of an unpleasant quality must precede 

 the appearance of warning colour. The properties that 



