i68 



THE SWAN AND HER CREW. 



emerges out of its case, just like the butterfly, and sails away a 

 perfect and gorgeous insect, leaving its case a transparent 

 brown shell, still clinging to the reed or grass-stem on which it 

 contracted its last change." 



" Bother the gnats ! " said Jimmy brushing some off his face. 

 " There is nothing interesting about them." 



" Oh yes, there is," said Dick. " They lay their eggs on the 

 surface of the water, making a raft of them, and the larvae 



METAMORPHOSES OF PLUMED GNAT. 



escape through the bottom of each egg into the water; and I have 

 read that it is a very pretty sight to watch the perfect insect 

 coming out/' 



" I would prefer their staying down below ; they bite me," 

 answered Jimmy. 



Crawling along the bottom were numbers of caddis-worms in 

 tube-like cases made of sticks and stones. Inside these cases 

 are the plump white grubs which turn into flies. 



"Where the bottom is gravelly these caddis-worms make 

 their cases of little stones," said Frank. 



