gravel, to drive the insects from it ; and sometimes, it 

 rushes into the fresh water, where these insects cannot ex- 

 ist ; and having thus obtained relief, it returns to its 

 natural haunt. Other wants and instincts of a similar 

 kind, likewise influence its motions. And thus it is, that 

 although the great body of the fish are always in the ocean, 

 numbers of them are in a continual state of transition, 

 from the ocean to the friths and rivers, and from the friths 

 and rivers back again to the ocean.* 



What has now been stated, involves the whole merits 

 of the question. In supposing that the river fisheries 

 are seriously affected by the success of the stake-nets, 

 it is assumed, that the fish which are captured below, 

 would have gone to the upper fisheries, if they had not 

 been intercepted. But this is not the fact. The fish which 

 are captured by the stake-nets, are not those which would 

 frequent the fresh waters. The latter are almost invariably 

 under the impulse of some powerful instinct ; and as it is 

 the habit of the fish, when so impelled, to take the direct 

 course of the mid-channel, they are thus seldom within 



* The insect by which Salmon are annoyed, after long re- 

 sidence in the sea, is called by fishermen, the sea louse. It ad- 

 heres to every part of their body ; but dies and drops off after 

 they have been a very short time in the fresh waters. Scarce- 

 ly, however, have the rivers become their temporary element, 

 than the Salmon grow wasted and diseased. Their appearance 

 gradually changes, and a species of worm, (said to be the hrnea 

 Salmonea of Linnaeus), now infests their gills. In the salt- 

 water, however, this worm cannot exist. And the fish soon 

 after their return to the sea, gradually recover their former 

 good condition and richness. 



