THE SALMON FISHEK. 45 



blooded bodies by vigorous gymnastic exercise. 

 They can only wait patiently for warmer weather. 

 Salmon, however, which have not passed above the 

 estuaries, often drop back into the ocean and remain 

 there until a more propitious time for another 

 attempted ascent, thereby constituting a second or 

 third run as the case may be. 



Varying conditions govern all the rivers of Europe 

 and America as well, so that it is inexpedient to at- 

 tempt to predicate the movements and habits of the 

 denizens of one river by those of another. In the Bay 

 Ohaleur, Canada, netters keep their snares out only 

 for a short time in spring, because the run is soon 

 over. The salmon drop back to the sea. In mid- 

 summer, in most Canadian streams, there is a 

 second run, because the rivers are kept full from 

 the reservoirs of still unmelted snow at their sources. 

 The water is cold, and marine forms are only just 

 beginning to enter these channels. In many rivers 

 the water gets low and too warm for the salmon to 

 remain, and they stay empty all summer unless a 

 " spate " comes. If all incomers remained they 

 would be too crowded to move, as in some rivers on 



