parisons, however, the x^ test for homogeneity 

 was significant ( x^ = 45.1, 12 d.f.); thus, indi- 

 vidual x^ for the north-south comparisons 

 showed that 1954 and 1955 had a significant 

 number of means to the north of the general 

 mean, but in contrast 1959 and 1961 had a sig- 

 nificant number of means to the south of the 

 general mean. 



Apparent Movement 



The relatively stable periodicity in the CPUE 

 spatial statistics suggested the possibility of 

 computing the velocity of the two-dimensional 

 first moment as it moves through space. We 

 call the movement deduced from this velocity 

 apparent movement because it could result 

 from several modes of actual movement. For 



30" 

 N 

 20" 



30° 

 N 

 20" 



10° - 



155° 160° 



LONGITUDE 



Figure 1 5. --Lat i tud i na I and longitudinal moments of effort for each month and 

 year. The center of the cross represents the average position of the lati- 

 tudinal and longitudinal moments for each month. 



20 



