98 THE LIFE OF THE SALMON 
growth in parr and smolt scales, and from these it 
is seen that when the smolt is fully two years old 
and has reached tidal water, preparatory to the 
first migration to the sea, the number varies from 
23 to 28. The scale is well defined, and bears upon 
it the traces which, as we shall presently see, remain 
in all older scale appearances. 
It is of special interest to note that in connection 
with the smolt-marking experiments in the Tay, to 
which reference has already been made, evidence as 
to scale growth was collected, and that when those 
wired smolts again turned up as grilse, and subse- 
quently also as small spring fish, the record of the 
scales was obtainable. It may be said at once that 
this record, as interpreted by previous study, was 
in complete harmony with the evidence obtained 
from the marking. 
I subjoin Mr. Johnston’s table, which refers to 
thirteen of the grilse recaptured in 1906 with smolt 
wires 4” situ :— ; 
