260 American Fisheries Society 



In following the figures down the column, it was found 

 in practically every instance that each form contains measure- 

 ments so close to the other that very likely one would unhesi- 

 tatingly pronounce the 'fish specifically identical. But with a 

 little closer scrutiny, it was observed that the percentages 

 practically throughout graded variably from a higher to a 

 lower or from a lower to a higher percentage in each form, 

 in some of the measurements in the order of the size of the 

 fish. 



This fact suggested averaging available percentages of the 

 two forms and flattening the variation by overlapping the 

 percentages from one group to another of equal number. 

 Taking 18 specimens of each form, five groups of six figures 

 each resulted. Group 1, composed of the smaller sizes, and 

 Group 5, of the larger sizes, were, of course, unaffected by the 

 overlapping. In this way it was found that there were con- 

 siderable variations, irrespective of the size of the fish, some 

 of which variations were possibly attributable to inaccuracy 

 or lack of uniformity of measuring between two points not 

 always positively determinable. 



Graphs of these results show, in many instances, more or 

 less crossing, which suggests individual variation not associated 

 with difference in size of the fish. But in others, they show 

 distinctly, and, in some cases, widely separated, more or less 

 parallel, converging or diverging upward or downward trends. 

 In but one or two instances, however, does the percentage of 

 one or more groups of one form remain wholly distinct from 

 that of one or more groups of the other. But where they 

 are alike in size ranges, the larger blue pike are nearly always 

 like the smaller yellow pike. 



The study of these measurements has not been completed, 

 but enough has been learned to suggest a divergence of the 

 two forms. An important point is that there are mature 

 breeding fish of both kinds in practically the same range of 

 sizes. In order to ascertain, if possible, the ages of the fish, 



