WATER MASSES AND CURRENTS OF THE OCEANS 197 



Philippine Islands a definite division of the current takes place, one 

 branch turning south along the coast of the island of Mindanao and the 

 larger branch turning north, following closely the east side of the northern 

 Philippine Islands and the island of Formosa. The intensity of the flow 

 to the south varies with the season, and the same probably is true regard- 

 ing the flow to the north. 



The Kuroshio System. After passing the island of Formosa the 

 warm waters continue to the northeast between the shallow areas of the 

 China Sea and the submarine ridge on which the Riukiu Islands lie. On 

 reaching lat. 30°N the current bends to the east and then to the northeast, 

 following closely the coast of Japan as far as lat. 35°N. The name 

 ''Kuroshio'' is particularly applied to the current between Formosa and 

 lat. 35°N, but, in agreement with the nomenclature used when dealing 

 with the currents of the Atlantic, and following Wiist, we shall apply the 

 name ''Kuroshio system'' to all branches of the current system and shall 

 introduce the following subdivisions: 



1. The Kuroshio: The current running northeast from Formosa to 



Riukiu and then close to the coast of Japan as far as lat. 35°N. 



2. The Kuroshio Extension: The warm current that represents the 



direct continuation of the current and flows nearly due east, 

 probably in two branches, and can be traced distinctly to about 

 longitude 160°E. 



3. The North Pacific Current : The further continuation of the Kuroshio 



Extension that flows toward the east, sending branches to the 

 south and reaching probably as far as long. 150°W. 



To these three major divisions of the Kuroshio system can also be 

 added the Tsushima Current, the warm current which branches off on the 

 left-hand side of the Kuroshio and enters the Japan Sea following the 

 western coast of Japan to the north, and the Kuroshio Counter current, 

 which represents part of a large eddy on the right-hand side of the 

 Kuroshio. 



The Kuroshio. The great similarity between the Kuroshio and the 

 Florida Current has been pointed out by Wiist. Wiist compares the 

 Kuroshio between the Riukiu Islands and the continental shelf to the cur- 

 rent through the Caribbean Sea, and the flow of the Kuroshio across the 

 Riukiu Ridge in lat. 30°N to the flow through the Straits of Florida. 

 This part of the Kuroshio, as well as the current to the south of Shiono- 

 misaki in lat. 33°N, long. 135°W, has been studied by Japanese oceanog- 

 raphers who have conducted current measurements and have occupied a 

 large number of oceanographic stations. According to Koenuma, the 

 current between Formosa and the southern Riukiu Islands reaches to a 

 depth of about 700 m, and the maximum velocity near the surface is 

 89 cm/sec. These figures are. based on computations, but are in good 



