104 



U.S. NATIONAL MUSEUM BULLETIN 291 

 63 61 59 . 57 . 55 . 5 3 



500 



1500 



2500 



Figure 21. — Vertical section, 25°W, 55°-63°S; temperature °C, oxygen concentration nil/L. 

 Capture points of Bathyteuthis abyssicola. 



The salinity section (fig. 22) in general shows low salinities through- 

 out the region. The 34.T0%o isohaline extends as a thin tongue to about 

 60°30'S at 600 m; at 57°S it is located between 650 and 1050 m and 

 encloses a thin tongue of high salinity water of 34,73%o-3-l:.74%o. Below 

 1100 m at 57°S and at all depths south of 61 °S the salinity is below 

 34.70%o ; the deeper w^ater is Antarctic Bottom Water of about 34.66%o 

 which flows northward and eastward into the major oceans. 



The density is uniformly high below the Surface Water and increases 

 rapidly from sigma-t = 27.50 to 27.82 (fig. 22) ; below 750-1000 m and 

 in the south the density is very high, above 27.85, due to the extremely 

 cold water. 



Oxygen concentrations are quite high along the entire section (fig. 

 21) ; minimum values south of the convergence range from 4.43 ml/L 

 to 4.81 ml/L. The layer of minimum oxygen in the south is from 300 to 



