142 THE UNIVERSE. 



order to disgust the insectivorous birds. Subsequently freed 

 from this filthy garment, it promenades upon the royal 

 plant in a magnificent carapace of vermilion. 1 



The bombardier beetles are even more ingenious ; they 

 alarm their enemies by means of real artillery. These Co- 

 leoptera, when threatened, suddenly expel from their intes- 

 tines a whitish acid vapor, the explosion of which, as it 

 issues, produces a slight detonation, which carries disorder 

 among the aggressors. This explosion may even be re- 

 peated a certain number of times. Hence, when one of 

 these insects is pursued by an enemy, it fires off its artillery 

 anew. The instinct of defence is so inherent in the tribe 



74. Lily Crioceris and its Larva: Crioceris merdigera (Leach). 



of bombardiers that at the sound of a cannon shot from 

 one of them all the others fire at the same time, there 

 is a running fire along the whole line. 2 The sound pro- 



1 The excrement piled upon the back of the Lily Crioceris forms an enormous 

 and heavy mass compared with the volume of the larva, which it entirely con- 

 ceals from view. We only see what appear to be little packages of moist defeca- 

 tions, walking upon the leaves of the plant. The worm deposits them on its 

 back as fast as they are produced, and that is done by means of a special or- 

 gan. The anal orifice, instead of being quite at the end of the body, is placed 

 above in such a manner that each globule of excrement is disposed in its proper 

 place, thus contributing to the increase of the mass in proportion as the animal 

 grows older. 



2 It is, according to Rolander, furnished with an apparatus which enables it to 

 discharge twenty shots in succession. Another less known species, the small 

 green beetle, Anchomenus prasinus, also fires off repeated discharges. It is found 

 near London. TR. 



