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 in situ : 



