POWER OF CONCEALMENT. 



359 



In looking at the Dragon Flies in a cabinet, or at their por- 

 traits in a book, scarcely anyone would see anything to denote 

 a power of concealment by means of resemblance to surrounding 

 objects. Yet many of the Dragon Flies possess this power in a 

 very remarkable degree, and I suppose that it is shared by all 

 On the wing, scarcely any insect is so conspicuous as a large 

 Dragon Fly, and yet I have often noticed that when at rest, and 

 on the watch for prey, scarcely any insect can escape the eye 

 more effectually. 



It might be thought that the large shining wings, which are 

 often decked with bold and conspicuous markings, must make 



Fia. 175. — Libellula Carolina. 

 (Wings with hrown patch at base.) 



the insect visible wherever it may settle. Yet, to judge by our 

 own species, these very characteristics aid the Dragon Fly in its 

 temporary and rapid concealment. When engaged in the search 

 for prey, the insect always manages to settle upon some object 

 with which its wings will harmonize in colour and general out- 

 line, a bunch of leaves being a favourite resting-place. There 

 it will sit with its legs all drawn together so as to be as little 

 conspicuous as possible, and with its motionless wings so com- 

 pletely merged into the surrounding objects, that, when the 

 insect suddenly dashes into the air, it seems to have started out 

 of space into existence. 



