64 MARVELS OF FISH LIFE 
two broad rings and seven narrow rings for the second 
summer and second winter in the sea; and, lastly, two 
or three broad rings for the spring growth in the sea. 
In May the fish was caught in fresh water. 
A glance at the scales as a whole shows the summer 
growth in the sea as a broad light band and the winter 
growth as a narrow dark band. / 
The second illustration shows another scale from the 
same fish. The particular points of interest in this 
photograph are, the clearness with which are shown the 
original scale, the first and second year’s growth as a 
parr, and the single broad ring of growth added to the 
scale at the commencement of the salmon’s third summer 
in the sea. 
By means of the systematic markings of smolts and 
other stages of the salmon, and the examination of 
scales carried out by numerous scientists all over 
the country, the life history of the salmon is now 
partially known. ; 
Our present knowledge points to the facts that the/ 
salmon alevin hatches about February, and lives in 
fresh water as a parr for over two years, then becomes a 
silvery smolt and goes to sea about May, that is, twenty- 
seven months after he has hatched. This fish spends the 
third year of his life in the sea, and may return as a 
grilse to fresh water in his fourth year. If he returns 
early in the year he probably weighs two or three 
pounds, but if not until the autumn he may weigh ten 
or twelve pounds. The grilse spawns and becomes a 
