32 
DEPARTMENT OF THE NAVAL SERVICE 
7 GEORGE V, A. 1917 © 
keeping spring salmon in rearing ponds for a year, it is decidedly unwise to do so, 
as, taking it either in size or in time, there must be a handicap of at least 20 or 25 
per cent. in favour of the “ sea-type” fish. 
Fic. 
oe 
oe 
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10. 
als 
12. 
13. 
14. 
EXPLANATION OF PLATES. 
PLATE I. 
Scale of spring salmon in third year showing summer growth at the margin, caught 
June 6. 
Scale of spring salmon near the end of the third year showing winter check at margin, 
caught February 16. 
Scale of spring salmon in second year showing winter check starting at margin, caught 
November 27. 
Scale of spring salmon in second year with winter check just starting at mare caught 
January 5. 
PraAtTEe U1. 
Scale of spring salmon at the beginning of the fourth year with summer growth start- 
ing at the margin, caught March 17. 
Scale of spring salmon at the beginning of the third year with summer growth well. 
begun at the margin, caught April 5. 
Scale of spring salmon at the beginning of the third year with no summer grovth show- 
ing at the margin, caught April 13. 
Scale of spring salmon at the beginning of the third fee with no summer growth 
showing at the margin, caught April 22. 
Scale of spring salmon in the third year, regenerated in the fall of the second year and 
showing the second winter check. 
PrArH toi: 
Scale of spring salmon in third year with 4. check showing at the margin during sum- 
mer growth, caught July 26. 
Centre of scale of spring salmon of “stream type” in fourth year, in which migration 
took place immediately after winter check. 
PLATE IV. 
Centre of scale of spring salmon of “stream type”’ in second year, showing fresh water 
growth after the first winter check. 
Centre of scale of spring salmon of ‘sea type” in second year. 
GRAPHS. 
A curve to show percentage.for each half month of the total growth for the year. A 
curve to show at the end of each half month, the percentage of the whole growth of 
the year attained. A curve (interrupted) showing the annual variation of the tem- 
perature of the surface water. 
A curve showing ratio of weight to length. 
