Nakagome, J. 1958. On the seasonal variation of swim- 

 ming layers of yellowfin tuna, big eyed tuna and 

 black marlin in the area of Caroline and Marshall 

 Islands. 1. On the seasonal variation of swim- 

 ming layer. [In Jpn., Engl, summ.] Bull. Jpn . Soc. 

 Sci. Fish. 23:518-522. 



Swimming layer depths of yellowfin were shal- 

 lower (115 m) in late spring and deeper (150 

 m) in autumn, changing seasonally. The 

 bigeye zone was shallower (110-120 m) in late 

 spring and from November to December, and 

 deeper (140-150 m) in the autumn and January, 

 changing seasonally. 



KEY WORDS: tuna, yellowfin, bigeye, depth, 

 " habitat. 



Nakagome, J. 1958. Relation between seasonal varia- 

 tion of swimming layer of yellowfin tuna and 

 big eyed tuna and vertical distribution of 

 chlorinity. [In Jpn., Engl, summ.] Bull. Jpn. 

 Soc. Sci. Fish. 23:523-524. 



No relation was found between the swimming 

 layer and vertical distribution of chlori- 

 nity. 



KEY WORDS: tuna, yellowfin, bigeye, season, 

 depth, habitat, chlorinity (salinity). 



Nakagome J. 1958. On the seasonal variation of swim- 

 ming layers of yellowfin tuna, big eyed tuna and 

 black marlin in the area of Caroline and Marshall 

 Islands. 2. Relation between seasonal variation 

 of swimming layer and vertical distribution of 

 water-temperature. [In Jpn., Engl, summ.] Bull. 

 Jpn. Soc. Sci. Fish. 24:169-172. 



Variation of the swimming layer of yellowfin 

 and bigeye was not related to variations in 

 water temperature. Therefore, the author 

 supposed that the swimming layer was indepen- 

 dent of temperature. 



KEY WORDS: tuna, yellowfin, bigeye, habitat, 

 depth, temperature. 



58 



