70 U.S. NATIONAL MUSEUM BULLETEST 291 



of the sample has only one lappet with 1 sucker and six lappets with 

 suckers; 16.6% has more lappets with than with 1 sucker, and only 

 8.3% has six lappets with suckers, one without. Therefore, over 90% 

 of the males have more lappets with suckers than with 1 sucker. In 

 contrast, females have no predominance of numbers of lappets with 

 or 1 suckers; there are as many lappets without suckers as there are 

 with suckers. Applying- these figures to Table III, it is found that 13.5 

 (=75%) of the 18 males with 0, 1 suckers would have only one lappet 

 with 1 sucker and six lappets with suckers. This further strengthens 

 the indication that males have fewer lappets with suckers and, in addi- 

 tion, they have fewer suckers. 



Figure 14 gives the plots of combinations of buccal suckers for males 

 and females against mantle length. The graph is a visual reinforcement 

 of the points brought out in the preceding discussion. In addition, it 

 shows a weak trend toward an increase in numbers of suckers (and 

 number of lappets with suckers) with increasing mantle length. The 

 and 0, 1 categories are represented by a broad range of sizes for males 



0,2,3. 



1,2. 



Buccal 

 Suckers 



ooooooo ooo o 



0,1,2. o o o o • • ''o o CO 



oo«oo a ooo*fO o« o o*9 *° f R° 8 °fi° * ° ° 



•^o g»« ..o. ttt**l**t°* 8 "5 8 • 



•Male 

 OFemalc 



fo 55 W~7, To 5^ 6^ 7*0 



ML , mm 



Figure 14. — Combinations of suckers on buccal lappets; Bathyieuthis abyssicola, Antarctic 



Ocean. 



