Parasites, Diseases and Enemies. 25? 



"8. Epidemics subside spontaneously, though the 

 fish remain in fresh water. 



"9. The productiveness of a salmon river is not .nec- 

 essarily interfered with by even a violent epidemic. 



"The last three propositions indicate the moral of 

 my paper which is to make sure that you know what 

 you are about before meddling with the salmon dis- 

 ease. Until the causes which convert the sporadic into 

 the epidemic disease are known, all interference is mere 

 groping in the dark; and when they are known, it will 

 be a great question whether the preventive measures 

 adopted are worth their cost. 



"Fishery doctors at the present day remind me of hu- 

 man doctors in my youth they were always for doing 

 something. I remember one of my teachers laid down 

 the notable maxim, 'when you are in doubt, play a 

 trump/ and I should think that those of us who have 

 followed this advice, in the last fifty years, -must have 

 largely added to the bills of mortality. Our fishery 

 doctors are of the same mind as my friend. They are 

 or at any rate ought to be very much in doubt, and 

 yet they continually want to play trumps in the shape 

 of stringent regulations and restrictions. If I might 

 tender a piece of advice, I would say don't." 



After quoting Huxley I can't help asking: If the 

 fungus (2) only lives on dead organic matter why it 

 attacks the living tissues of fish? 



A DEAD HORSE. 



Years ago a man asked me to come and see what 

 was the trouble with his trout and eggs. As he put it : 

 "There was wool growing all over them." I told him 



