12 THE ROYAL SOCIETY OF CANADA 
Some individual exceptions to this regular cycle occur. Thus 
Babcock has found that a considerable number of fry instead of seeking 
the sea in the spring following their hatching, remain an additional year 
in fresh water, migrating to the sea only in their second year. And 
another class of exceptions is formed by undersized but fertile males 
which accompany the full grown fish on their way to the spawning 
grounds and are known as grilse. I was able to obtain some examples 
of these fish, and a study of their scales in comparison with those of the 
full grown fish has yielded some interesting data. 
THE SCALES. 
The scales of ten adult Sockeye Salmon were examined, all the 
fish being taken at the mouth of the Fraser River and obtained at the 
Phoenix Cannery, Steveston. The fish varied in length from 63 cm. to 
69.5 em., the measurement being taken in every case from the tip of 
the snout, over the body, to the free edge of the caudal fin at its middle. 
Scales were taken from each fish from the same region, namely, from 
what may be termed the shoulder region, and after removing the 
adhering epithelium they were mounted dry between glass slips, retained 
in position by strips of passe-partout. 
In a scale thus prepared one sees (Plate 1) upon the protected 
portion a large number of lines arranged concentrically about a nucleus, 
which is not, however, at the centre of the scale, but much nearer the 
exposed free margin than the protected one. On the exposed portion 
of the scale the concentric lines are as a rule indistinguishable, but on 
the protected portion they are seen at a glance to be differently spaced 
in different regions. Immediately around the nucleus there is a number 
of lines which succeed one another with very narrow intervals, forming 
a well marked zone readily distinguishable from the succeeding lines 
which are much more widely spaced. The narrow lines, as they may 
for convenience be termed, seem to represent the period spent by the 
young fish in fresh water; together with the nucleus they represent the 
first winter of the fish’s existence. 
Succeeding these narrow lines, there comes a broad zone showing 
widely spaced lines, to be interpreted as marking a period of rapid 
growth during the first summer spent in the sea. As these rings or 
lines are followed outwards from the centre they are seen to become 
narrower and sooner or later form another clearly distinguishable zone 
of narrow lines. These represent a winter check in growth, so that the 
zone of broad lines plus that of the narrow ones represents the first year 
spent in the séa. 
