of these vater masses. The symbols vhlch appear on the T-S station 

 plots correspond to the symbols vhich Identify the station locations 

 on the chart. In order to show the extent of the typically Arabian 

 Sea water^ tvo sets of ocean stations vere selected. The first set 

 extends in a west to east direction beginning in the Gulf of Aden 

 near the Bab el Mandeb Strait and terminating near the island of 

 Ceylon. The second set of stations are located along a north-south 

 line originating in the Gulf of Oman near the entrance to the Persian 

 Gulf. The southernjnost station of the second set is located at about 

 3°N. The NODC cruise number^ station number^ ship^ and year for each 

 station in the plot are listed in Tables 1 and 2. From an observation 

 of the T-S plots and station locations it is quite apparent hov the 

 Arabian Sea water masses undergo change as they proceed from their 

 region of origin. The salinity decreases gradually from west to east 

 and from north to south and the T-S profile for the last station of 

 each set is no longer typical of the Arabian Sea water. Instead 

 these last stations fall within the T-S envelope of the Indian 

 Equatorial vater^ although they still carry a strong Arabian Sea in- 

 fluence. The boundary of the Arabian Sea water was thus determined 

 by the merging of its T-S envelope into that of typical Equatorial 

 vater. 



16 



