BATHYPELAGIC SQUID BATHYTEUTHIS 



195 



many of these were captured while the nets were passing through the 

 shallow layer of abundance, and the lower limit for Brachioteuthis 

 picta is probably much shallower than 2250 m, perhaps around 1000 m. 



3. Gonatus antarctlcus Lonnberg, 1897 



The only other pelagic cephalopod that has been caught in the South- 

 ern Ocean in any quantity is Gonatus antarctlcus Lonnberg, 1897. A 

 total of 141 specimens was captured during the same period that 598 

 specimens of B. abyss'icola were taken. Therefore, the relative abun- 

 dance for specimens captured by all means is 4.2 specimens of B. ahyssi- 

 cola to each Gonatus antarcticus. G. antarctlcus is primarily a shal- 

 low living form (Table XX, fig. 74) ; 55% of the sample population 

 was taken in the upper 250 m; 30% was distributed between 250- 

 1000 m. The sharp drop-off in catches between the 750-1000 m level and 

 the 1000-1250 m level from 21.4% to 0.7% indicate that G. antarctwux 

 does not normally live deeper than 1000 m and that the captures below 

 that depth probably were made in the shallow zone of abundance. 



It seems curious that the most abundant cephalopod in the Antarctic 

 Ocean is a bathypelagic species that apparently outnumbers its closest 

 rival nearly 2 to 1. The three most common species besides B. ahyssinolu 



Figure 74. — Vertical distribution by 250-meter increments of the total sample population of 

 Gonatus antarcticus Lonnberg, 1897. Antarctic. 



