AGE DETERMINATIOX FROM SCALES OF LAKE TROUT 21 



2 3 4 5 6 7 



GROWTH 



Fici-RE 13. — Scale of a lake trout 26.2 inches long with left pectoral fin abnormal allhouKh the type of abnormality was 

 not described. Caught June 13, 1947. If thi.s lake trout had been marked by the removal of the left pectoral fin, 

 it would have been 1 year old, but it is too large for that age, and 8 checks were on the scales. (See text for dis- 

 cussion of the central check). Xew growth was not uniform in width. On this section, new growth appears only in 

 the lower right area. The deformed fin was an abnormality. 



