72 U.S. NATIONAL MUSEUM BULLETIN 291 



2. Bathyteuthis abyssicola — Eastern Pacific 



Seven specimens of B. abyssicola from the eastern Pacific exhibit 

 five combinations of numbers of buccal suckers. The smallest specimen, 

 13 mm ]ML, has 1, 2 suckers while the remaining specimens (16-30 mm 

 ML) have 2, 3; 3, 4; 3, 4, 5; or 4, 5 combinations of suckers (fig. 15). 

 The indication is that suckers are added very rapidly to the lappets 

 during growth, following the general trend of B. hacidifera from the 

 same waters. Slight overlap of buccal sucker combinations occurs be- 

 tween ahyssicola from the eastern Pacific and from the Southern 

 Ocean. When overlap does occur between populations, a significant 

 difference exists in the size of specimens that share a number-combina- 

 tion. B. ahyssicola of 13 mm ML from the eastern Pacific has the 1, 2 

 combination of suckers; several Antarctic specimens have this combi- 

 nation (12% of the total sample) , but only one is less than 31 mm ML. 

 Three eastern Pacific abyssicola^ 18, 19, and 22 mm in ML, have a 



2, 3 combination and a single Antarctic specimen, 51 mm, has a 0, 2, 3 

 combination ; this specimen has the highest combination of suckers 

 of all the specimens from Antarctic waters. The 20-30 mm size range 

 in abyssicola from the eastern Pacific has combinations of 3, 4, and 5 

 suckers ; the same size group from the Antarctic has ; 0, 1 ; and 0, 1, 2 

 (2 specimens) combinations. 



3. Bathyteuthis abyssicola — Atlantic 



The combination of buccal suckers of 20 specimens of abyssicola 

 from the Atlantic are plotted on figure 15. Again, the trend toward in- 

 creased numbers of suckers with increasing size of the animal is ap- 

 parent. The 11 specimens below 23 mm ML (9 below 20 mm) have the 

 combinations 1, 2 ; 1, 2, 3 ; or 2, 3 ; the smallest size within each category 

 increases with increasing numbers of suckers. Nine specimens range 

 in size from 33 to 49 mm ML; two-tliirds of these have combinations 

 of 3, 4, 5, 6, and 7 suckers and five of these six have no fewer than 4 

 suckers on each lappet. 



B. bacidifera and abyssicola from the eastern Pacific apparently 

 attain larger numbers of suckers at smaller sizes than does abyssicola 

 from the Atlantic. That is, the 3, 4, 5 combination is found on a 30 mm 

 Isilj specimen in the eastern Pacific and a 38 mm* specimen from the 

 Atlantic ; the 4, 5 combination is found on a 25 mm bacidifera and a 

 22 mm ahyssicola from the eastern Pacific and on 45 and 47 mm 

 specimens of ahyssicola from the Atlantic. 



Half of the Atlantic abyssicola are 20 mm or less in ML and none 

 of thQ specimens exhibit the ; 0, 1 ; or 0, 1, 2 combinations. In Ant- 

 arctic ahyssicola 86% of the sample population falls into tliese three 

 categories and 75 %o into the or 0, 1 groups; 15.5% of the and 0, 

 1 specimens are under 20 mm while no specimens under 25 mm occur 



