216 ON THE GROWTH OF THE SALMON. 



water comparatively deep? Even in rivers, salmon, 

 while spawning, resort to the shoals, instinctively by 

 doing so courting for their deposit the action of solar 

 heat, in order to vivify and hatch it ; and it is plain, 

 from the size and nature of the pellets, compared with 

 those of other marine fishes, such as cod, &c., that they 

 require this action. 



That salmon do not, as alleged by some, breed in salt 

 water, may also be inferred from the circumstance that 

 they are seldom or never met with on those coasts 

 where the breeding streams are not of sufficient size to 

 admit of their ascent. Along the shores of Great 

 Britain and the sister island, where there are so many 

 contiguous streams and friths, it may be difficult to 

 adduce .a single instance in illustration of this fact. I 

 have ascertained, however, that around the Shetland 

 Islands, where there are numbers of small streams suffi- 

 cient in run to favour the breeding of sea-trout, that 

 these fish are proportionably abundant, but that the 

 true solar, which the rivulets referred to are unable to 

 accommodate, is not known in their vicinity. 



Having thus stated my objections to the notion that 

 salmon breed as well in salt as in fresh water, I am led 

 back to the subject started from, namely, the transition 

 of the parr or smolt into the grilse. I have already set 

 forth my reasons for believing that this transition is very 

 rapidly effected. They are simple, but strong. The 

 only objection which it is possible to cast up against 

 them is supplied by myself in the preceding relation, as 

 to what fell under my notice, respecting the gradual 

 growth of the orange-fin, or sea-trout fry, into the 

 finnock. But this is an objection very easily disposed of. 



The salmon or solar and sea-trout are distinct species 

 of fish. The one, as we find it, attains a much larger 



