SAT.AION. 191 



have gone doAvn to the sea will, unless under very extraordinary 

 circumstances, return to the river of their 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." 

 The 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 Avhich 

 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 from 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 Avhich do not quit the sea through the summer, although 

 others of probably the same brood press towards the fresh 

 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 

 formation, does not exist; as also it seems certain that there 

 are some in which the procreative impulse only revives Avith 



