SALMON. 
191 
ave gone down to the sea will, unless under very extraordinary 
circumstances, return to the river of thei>- birth; while the 
guiding influence in doing this is beyond our powers to com- 
prehend. But in the work by Ephemera, already referred to, 
we find an instance of this, which illustrates this habit in a 
manner beyond what we could have supposed:— 
Loch Shin is a large piece of water in Sutherland, from 
which proceeds the River Shin, “noted for its Salmon fecundity.” 
Ihe loch Itself is supplied with water from four rivers of 
moderate size, but in which, before the year 1836, “not a 
Salmon was ever seen, though many were in the habit of 
entering the loch.” But in the year now mentioned, Salmon 
were caught in the River Shin shortly before the breeding- 
season, and conveyed to the four rivers above; in each of which 
some of them spawned, and from that time each of those rivers 
is furnished with fish, and each of them with its own, which 
pass by and beyond the stations which their ancestors frequented 
to enter the higher rivers, of which they are now the natives. 
The fish which thus pass up the stream fr-om the sea are 
readily distinguished from such as have been long in fresh water 
by their brilliant colour, which in no long time subsides into 
a darker hue; but although the growth appears to be presently 
arrested, it is without decrease of strength or activity; for it is 
in the experience of anglers that a Grilse which has been 
longer in the river will put his tackle to a more severe trial 
than a Salmon of larger size that has only lately arrived. It 
has further been noticed of late that there are Salmon and 
Grilse which do not quit the sea through the summer, although 
others of probably the same brood press towards the fre*sh 
water; and further, that there is no small number which do 
not seek to breed when others of the same age are performing 
that function; and why this is so we scarcely venture to guess; 
but these circumstances tend to explain how it happens that 
there are fish in high condition in many rivers, and in some 
much more than others, at times when the generality are far 
otherwise. The natural history of many rivers is closely con- 
nected with this, and the interests of fishermen greatly so; but 
It IS probable that a really barren Salmon, except of unnatural 
oimation, does not exist; as also it seems certain that there 
some in which the procreative impulse only revives with 
