48. ORIGIN OF THE SILVER EEL. 



with a compound nature. I place it in my 

 third class. It is very like the eel-beetle, 

 because it breeds on land, and changes its 

 form to live on the water. 



This fly is about five-eighths of an inch 

 long, of a slender make, with long thin legs. 

 It is of a dark colour, and its wings are clear, 

 tinged with a shining bluish red. It breeds 

 in the sandbanks on the rivers of Scotland. 

 It rises out of the sand, and pairs about the 

 beginning of June, depositing its ova among 

 the grass on the bank, wherever it is thin. 

 The ova remain among the roots of the 

 grass until the hot sand brings them to life, 

 when they work down among it, beyond 

 the reach of the frost. In the following 

 May, when the banks become heated with 

 the sun, it appears in the shape of a small 

 grub. It then goes into chrysalis, and 

 comes out about the 1st of June, the dark- 

 coloured fly previously described. It chooses 

 a bank not far from the river, and is con- 

 stantly going between the bank ' of sand 

 where it was hatched and the water. It 

 has the power of flight, but generally walks, 

 and when it comes to the water, it travels 



