Kendall. — Blue Pike and Yellow Pike 261 



scales were taken and mounted ; but they have not been studied 

 carefully enough to arrive at any positive conclusion. Photo- 

 graphs have been made of several of each which show, al- 

 though not as distinctly as one could wish, certain lines of 

 growth, whatever they may signify. If the crowded lines 

 are interpreted in the same way as in the case of salmon scales, 

 they indicate that some of the smaller blue pike are older than 

 some yellow pike of larger size. 



The lack of time and the incompleteness of study of the 

 measurements do not permit a detailed consideration of results 

 at the present; but I shall refer to six of them which will 

 indicate what measurements may be of importance in deciding 

 the relationship of these two forms, especially when a large 

 series of each of an equal range of size is studied and compared. 



The overlapping groups referred to were respectively com- 

 posed of fish of average total lengths, as shown in the follow- 

 ing table of total lengths, given in millimeters. 



Average Total Lengths of Groups 



Group numbers and averages General 



Kind 12 3 4 5 Average 



mm. mm. mm. mm: mm. mm. 



Yellow Pike 210 269 303 331 416 306 



Blue Pike 296 317 343 367 400 344 



These averages, arranged in the order of size from the 

 lowest up, are as follows : Yellow, 210 mm. ; yellow, 269 mm. ; 

 blue, 296 mm.; yellow, 303 mm.; blue, 317 mm.; yellow, 331 

 mm. ; blue, 342 mm. ; blue, 367 mm. ; blue, 400 mm. ; yellow, 

 416 mm.; yellow, average, 306 mm.; blue, average, 344 mm. 

 These figures show a fairly close running sequence of both 

 forms, with the exception of the first average of yellow pike, 

 which reduces the general average of that form. 



In order to check up the results shown in the group 

 averages, 6 fish of each form of approximately the same 

 lengths were selected. These range from a little over 280 mm. 

 to 370 mm. in length. The sexual condition and the over- 



