8 5£6G04 Sie6 804 8 926X04 6l£6m8i3Z£l404 tae 



Body Length 



Figure 2. --Length frequency by fishing area. 



among the years of each group, but there are 

 conspicuous discrepancies between the two 

 groups. To state it concretely, it is probably 

 possible to point out the existence of biennial 

 cyclical phenonnena in the positions at which 

 the modes appear and in the degree to which 

 they appear. If we try to examine these phe- 

 nonnena in figure 2, where the data are pre- 

 sented separately by sea areas, they are un- 

 clear in the area of 130 -140 E. and east of 



o 

 180 , where data are scarce, but they are 



clearly discernible in all of the areas for 

 which there is much data, 140 -150°E., 150 - 

 165 E., and 165 E.-180 . There are many 



points which should be examined from various 

 angles with regard to the existence of a biennial 

 cycle, and these points will be taken up below. 



The matters pointed out above are all 

 phenomena which appeared from the data, and 

 it is thought that such things as the general 

 correspondence of the positions of the modes as 

 between the several sea areas, and the evidence 

 of common tendencies in different years as re- 

 gards the relative strength with which the modes 

 appear in different sea areas can hardly be 

 thought to be accidental a>greements arising 

 from defects in the data, and can be considered 



26 



