VARIETIES OF SALMON. 7 
the accurate determination of species, artificial propagation 
will prove an invaluable ally of the fishery legislator as 
well as of the fish-culturist; and it is in this, as well as in 
such work as re-stocking barren waters, in facilitating an 
interchange of varieties between one district, or one country, 
and another, that artificial breeding will find its most 
useful functions. Not the least important service it can 
render is to aid in the accurate classification of the 
different varieties of Salmonide. 
Scientifically the genus Salto embraces two distinct 
classes of fish—those which migrate to and from the sea, 
and those which live entirely in fresh water. With the 
latter which include the fish known under the designations 
of trout, char, grayling, pollan,, powan, vendace, and 
ewyniad the present treatise has nothing to do. The 
non-migratory Salmonide are a mere incident—though a 
not unimportant one—in the greater question of the Salmon 
Fisheries. The same may be said of the smelt or sparling, 
which, though a migratory Salmonoid, differs so essentially 
in its habits from all the other varieties of the genus that 
it is not, in effect, placed under the salmon laws, and may 
be at once dismissed—although in an exhaustive con- 
sideration of the salmon question this fish ought not to 
be overlooked, since it undoubtedly affords in certain 
localities a large supply of food for the salmon. All these 
fish, it should perhaps be added, are susceptible in the 
highest degree of all the advantages which practical and 
systematic artificial propagation on the largest scale can 
confer. 
Of migratory Salmonide there is a large number of 
different species, and a still larger array of “ varieties.” 
Salmo salar is regarded in this country as the salmon par 
excellence, its cousins, the peal, sewin, or sea-trout-— 
