44 THE LIFE OF THE SALMON 
were, returning home. It is essential for this argu- 
ment that the salmon be regarded as a fresh water 
fish which has gone to the sea to feed. This forms, 
I admit, a plausible explanation of the presence of 
early running fish in our rivers. That they do not 
nourish themselves in fresh water has been proved. 
Whether they can be said to feed in fresh water 
must not be discussed here. This point, about 
which so much has been written, is really not very 
important. It is in essence a dispute about terms. 
Let us be thankful we can catch them with flies and 
other baits. 
But can the salmon be properly regarded as a fresh 
water fish? Dr. Noél Paton realises the importance 
of this for his argument when he says, in dealing 
with the factors determining migration, in the 
general summary (p. 169): “In considering the 
question it must be remembered that the Salmonidee 
are originally fresh water fish, and that the majority 
of the family spend their whole life in fresh water.” 
To my mind it is not clear that the majority of the 
family do so spend their lives, but further, it is not 
sufficient to regard the British Salmonide in this 
matter ; we must take into consideration the group 
of fishes, or at least the sub-order, to which the 
Salmonide belong, and judge the salmon as it 
appears in relation to its near allies. Ifin this way 
we take the seventeen genera of Boulenger’s classifi- 
cation, we find that the majority are more marine 
than fresh water, including Bathylagus (Gthr), the 
deep sea form recently added to the British fauna * ; 
* Holt and Byrne, “Fisheries Sci. Invest. Ireland, 1905,” II. 
(1906.) 
