16° 17° ISO 190 20^^ vl- xl2- 23° 24°C 00 



Figc2a Distribution of the average number of fish per catch (n) and the 

 number of catches of tuna (f) xn relation to the surface temperature 

 (Qq) on the tuna groands south of Boshu in December, 1930^ and 

 January, February „ ac'l March 5, 1931 » 



^ times 



+ 16 



l6/-> 17*^ -o-^ 19° 20° 21*^ 22= 23°C 6 

 Fig»2b Distribution of the average number of fish per catch (n)and the 

 number of catches of tuna (f) in relation to the temperatures at the 

 100m level (9)- on the tuna grounds south cf Boshu in December, 1930, 

 and Jan-dar-- February, ana March,, 1931. 



10 



