LIFE HISTORY OF LAKE HERRING OF LAKE HURON 



317 



data suggest that in both the herring and the whitefish scale formation begins at a 

 fish length of approximately 35 to 40 millimeters. 



Superficial observation of the whitefish series reveals at once that the body- 

 scale ratio in this species decreases rapidly with an increase in the length of the fish, 

 dropping from 109.87 in the 41-millimeter specimen to 56.20 in the 73-millimeter 

 fish, a decrease of 53.67. The average ratios of the juvenile whitefish and herring are 

 considerably higher than those of the older individuals of the same species. The 

 same is true for the related tullibees, whose ratios lilvewise decrease with size and 

 with age. 



Table 13. — Growth relation beiweeri body and scale for juvenile coregonids 



1 Plate. 



