curve vrill fall off sharply,, For the females the peak will 

 appear between 100 and 120 kgo ^ above and b .^ow which point 

 the frequency will gradually decline in a gentle curvec 



bo In the white marlin the males reached a maximum 

 weight of about 120 kgc , and there were almost none over this 

 weighto The most numerous size group was from 40 to 60 kgo 

 The females ranged from 20 to a maximum of 560 kgo, but they 

 were most numerous between 100 and 140 kgo A curve of size 

 frequencies shows the same general form as in the case of the 

 black marlino Almost no fish of either sex weighing less than 

 20 kgo were caughto 



Co In the other species size differences between the 

 sexes are inconspicuouso Data are also meager, and the size of 

 the fishj which even in the striped marlin rarely exceeds 100 

 kgo p is still smaller in the other species^, so in a comparison 

 using 10 kgo as the unit it is believed that no difference in 

 size between the sexes would appearo 



Since, as explained above, the sex ratios vary with the 

 seasons and the sexes differ in size, it is only natural that 

 there should be seasonal variation in the size of fish that are 

 takeno An attempt has been made to clarify this using the 

 individual weight data from all of the fish of each species 

 landed at Takao and SuOo The data cover the years 1942 and 

 1943o 



The facts which were made clear as a result were briefly 

 as follows^^V; 



ao In the black marlin the average body-weight gradually 

 increases from January to April and reaches its peak in the 

 latter montho The average for January is slightly over 90 

 kgo s while that for April is about 120 kg. After May there is 

 a rapid declinej and the minimum of about 65 kg„ is reached in 

 Augusta In September the average weight begins to increase 

 rapidly, and in October it is almost equal to the January figure. 

 In November it is around 80 kgo „ and in December it again 

 nearly equals January's marko The greatest number and weight 

 of fish, however, are taken in Julyo 



bo In the case of the white marlin, too, the curve 

 follows the same trend as that of the black marlin, but the 

 periods in which the maximum and minimum sizes appear are about 

 3 months later than for the black marlino 



(9) 



Nakamura, Hiroshio 1945o Studies on the Istiophoridae of 

 Formosan Waters, 8, Seasonal Differences in the Size of 

 Fisho Proco Formosan Nato Hist„ Soco , Volo 35, Octo , Deco 



52 



