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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



FiGt'RE 4. — A scale from a 4-year-olcl lake trout 15.3 inches long, marked in September 1945 and recovered May 7 or 9, 

 1949, showing the degree to which annuli mark the inner surface of the scales. The outer surface of another scale from 

 the same fish is seen in figure 8. The photograph is a negative of an impression in plastic. 



