THE TYRANT OF THE POOL 31 



very closely together, keeping the air in and 

 the water out. 



When the oxygen in his little air-tanks 

 becomes exhausted, the beetle rises to the 

 surface, sticks his tail out of the water, and 

 takes in a fresh supply. He opens his wing 

 cases a little way, and 

 the air clings to his 

 hairy coat, forming a 

 large, flat bubble on his 

 back. Then when he 

 has filled his tank, he 

 closes his wing cases and 

 darts away, feeling much 

 refreshed. 



In his early days this 

 Brown beetle is just as 

 much a tyrant of the 

 pool as when he is a 

 grown-up perfect insect and an ugly, ill- 

 conditioned young grub he is to be sure. 

 When full grown he is over two inches long 

 and a dirty-looking, yellowish-brown colour. 

 His body is long and clumsy, thick in the 

 middle, but tapering towards the head and tail. 

 His head is large and flat and almost round 

 in shape, and is joined to his shoulders by a 



, 



1111KL) LE(; OF BROWN 

 WATER-BEETLE. 



