BATHYPELAGIC SQUID BATHYTEUTHIS 



77 



2. Bathyteufhis ahysHicola vs. B. hacidlfera 



The difference in numbers of suckers is most pronounced between 

 ahyss'icola from Antarctic waters and hacidifera from eastern Pacific 

 equatorial waters. B. hacidifera has a greater number of suckers on 

 each of tlie arms except in very young specimens (fig. 17). Larvae of 

 both species at about 6 mm ML have nearly tlie same number of suck- 

 ers, but during the next 3-6 mm of growth hacidifera adds suckers 

 more rapidly than abi/snicoJa^ so that the first three pairs of arms have 

 from one-third to nearly one-half more suckers, and the fourth arms 

 have nearly twice as many (Table V). With continued increase in 

 mantle length the divergence in numbers of suckers increases gradually 

 in the first three pairs of arms from about 40% more to T5% more 

 suckers in hacidifera than in ahyssicola. The fourth arms of hacidifera 



140- 



120- 



100 

 Average 

 Number 

 Suckers 

 Arms l-IV 



40 



• B. obyssicolo 

 o B. bacidifera 



• 8 



ArmI II III IV 

 5.6/6 



U 15/17 18 19/19 23 29/26 3339/37 49-75/- 



Size Group, ML, mm 



Figure 17. — Average number of suckers on the arms of Bathyteuthis abyssicola (Antarctic) 

 and B. bacidifera. Size groups are divided into mantle lengths of B. abyssicola/ B. bacidifera. 



