WINGED ENEMIES OF BROOK TROUT. 



SOME idea of the serious loss of fish and fish- 

 eggs caused by myriads of enemies in and 

 about the waters is conveyed in a paragraph 

 of Dr. Day's book upon the British and Irish 

 SalmonidiZ. He says : " So enormous is the loss which 

 occurs among the eggs and young, that in such a river 

 as the Severn the annual produce of salmon and grilse 

 at the present time (1887) consists of about 20,000 

 fish. Were all the ova of one female salmon of about 

 twenty pounds' weight to be hatched and attain ma- 

 turity, they would suffice for keeping up the stock to 

 its present condition." The Severn is 2oo miles long 

 and receives five principal tributaries. 

 129 



