486 Dr KNOX on the Natural History of 



Man himself, then, is the greatest enemy of the smolt. Some 

 have thought that by floods the fords or shallows containing the 

 spawning beds may be entirely removed or covered with a new 

 load of sand and stones, and in this manner thousands of ova for 

 ever lost ; but there is not on record any properly authenticated 

 fact of this kind. Sudden changes, no doubt, do take place in the 

 beds of rivers ; but, so far as my personal observation extends, I 

 feel inclined to say that these are not very common. The same 

 streams and pools observed many years ago, I find in most in- 

 stances to exist ; and so far as I have observed, the changes which 

 do go on in the beds of rivers are rather gradual than sudden. 

 The interest of the neighbouring proprietors are generally hos- 

 tile to such changes, and usually oppose it to the utmost by 

 breastworks, &c., whether the ground be valuable or not. Mr 

 FRASER, a practical fisherman of great experience, has taken no- 

 tice of the king's-fisher, eels, flounders, &c. as being natural ene- 

 mies of the salmon fry ; but it is easy to understand that nothing 

 of all this is proved, and indeed every day these natural enemies 

 are reduced by the investigation of some naturalist. The 

 flounder for instance, does not seem to me much to leave the 

 brackish water ; and it has not been any where proved that any 

 of the salmon species breed in this locality. 



The spawning of salmon ceases, I should think, in all rivers 

 in or about the end of February *. Experienced fishers have 



* The following statements, derived from the Evidence before the Committee of 

 the House of Commons, are founded on tolerable evidence : 



Wales (Brecon). " Has seen many spawn in the middle of February, never 

 saw a fish spawn in March." 



Cork (Lee). " Spawn in October and November." 



Counties of Cromarty and Sutherland (Shinn, &c.) ' Salmon spawn early in 

 the month of October, all the breeding fish have passed up, and before the end of 

 November the spawning is over." 



Inverness (Beauly). " They spawn the latter end of October." 



Aberdeen (Don and Dee). " They have all done spawning by the 1st February." 



Berwick (Tweed)." Salmon spawn in January and February." 



