BATHYPELAGIC SQUID BATHYTEUTHIS 197 



Summary and Conclusions 



1. A historical resume traces the systematics and distributional rec- 



ords of Bathyteuthis dbyssicoJa Hoyle, 1885. 



2. The name B. abyssicola Hoyle, 1885, is shown to have priority over 



Benthoteuthis megalops Verrill, 1885. 



3. A redescription of B. abyssicola from the type region, the Antarc- 



tic Ocean, is presented ; the species is illustrated in detail. 



4. A study of morphometric features demonstrates the growth charac- 



teristics of B. ahyssicola. 



5. Two additional species of Bathyteuthis^ B. hacidifera and B. 



herryi^ are presented and illustrated from the eastern Pacific 

 Ocean. 



6. The taxonomic and morphometric characteristics of the species 



of Bathyteuthis are compared. 



7. Distinct geographical variation exists between populations of B. 



abyssicola from the Antarctic, eastern Pacific, and Atlantic 

 Oceans. 



8. Characters that vary geographically include the number of suckers 



on the buccal lappets, the number of suckers on the arms, and 

 the size of the gills. 



9. Gill sizes are shown to be related to the oxygen content of the en- 



vironment; large gills may be a mechanism for more efficient 

 respiration in areas of low-oxygen availability ; e.g., in the east- 

 ern tropical Pacific. 



10. The relationship between Bathyteuthis and Ctenopteryx is exam- 



ined and the family Ctenopterygidae is reinstated. 



11. The familial relationships of the Bathyteuthidae to other groups 



of oegopsids are surveyed; the family exhibits no close rela- 

 tionships and holds a distinctive position within the Oegopsida. 



12. The oceanographic features of the Antarctic Ocean are reviewed. 



13. An analysis of the physicochemical parameters of the Antarctic 



Ocean (temperature, salinity, oxygen, and density) is presented 

 on vertical sections along meridians 25°, 35°, 55°, 65°, 75°, 115°, 

 130°, 160° west and along 60° south latitude between 25° and 

 160° west. 



14. The distribution of B. abyssicola in relation to these parameters in 



the Antarctic Ocean is analyzed. 



15. The geographical distribution of B. abyssicola in relation to water 



masses in the oceans of the world is analyzed. 



