BATHYPELAGIC SQUID BATHYTEUTHIS 151 



are favorable for Bathyteuthis : less than 6°-7° C with an average 

 salinity of 34.98%o. Since B. ahyssicola has been taken in the east- 

 ern Atlantic in less than 1000 m on several occasions it seems likely 

 that it could easily enter the Caribbean and Mexican Basins over the 

 sills. In addition, it seems possible that a resident population of this 

 species could exist in Caribbean and Gulf waters, because the Panama 

 I)ortal was probably open to deep-water communication between At- 

 lantic and Pacific bathypelagic populations until the Upper Creta- 

 ceous (Schuchert, 1935). With the presence of seemingly adequate 

 temperature and salinity conditions, other factors must exist to limit 

 occurrence of B. ahyssicola. in the Gulf and Caribbean waters. 



The T-S capture diagram for the Atlantic Ocean (fig. 51) shows 

 tliat B. ahyssicola occurs in both North and South Atlantic Central 

 Water Masses. Only four captures are plotted in the North Atlantic 

 Central Water, Two captures, consisting of two larvae, were made in 

 the North Central Atlantic between about 40° and 47°N at 1500 m 

 where the temperature is just below 3° C and the salinity is about 

 34.90%o ; the remaining two captures, also consisting of 2 larvae, came 

 from 1500 m in the southern limits of the North Atlantic Central 

 Water Mass where tb.e temperature is above 3° C and the salinity is 

 above 34.95%o, due to the outflow of saline Mediterranean Water. The 

 plots of the captures between 1300-1800 m in the South Atlantic Cen- 

 tral Water overlap with those from the North Atlantic where oceano- 

 graphic conditions are similar. Deeper tows (over 2000 m) from the 

 South Atlantic also partly overlap with similar conditions in the 

 North Atlantic. The deepest tows from around 3000 m lie in the zone 



Figure 50. — Geographical distribution of Bathyteuthis. Numbers indicate previous records of 



Bathyteuthis ahyssicola (Table I). The hatching in the western sector of the Antarctic 

 Ocean represents Bathyteuthis ahyssicola captured by the Eltanin. 



1 = Hoyle, 1885 e = 5. ahyssicola — Eltanin 



2 = Verrill, 1885 e = 5. hacidifera— Eltanin 



3 = Hoyle, 1904 d = 5. ahyssicola — Dana 



4 = Chun, 1910 d = 5. hacidifera— Dana 



5 = Hoyle, 1912 p = 5. ahyssicola— Pillsbury 



6 = PfeflFer, 1912 c = 5. ahyssicola— Chain 



7 = Joubin, 1920 o — B. ahyssicola — Oregon 



8 = Thiele, 1921 pe=5. ahyssicola— Pelican 

 9=Robson, 1921 s = 5. abyssicola—Silver Bay 



10 = Odhner, 1923 v = 5. berryi—Velero 

 ll=Joubin, 1924 



12 = Robson, 1932 



13 = Robson, 1948 

 14=Voss, 1956 



15 = Massy, 1916a 



16 = Massy, 1916, 1928 



