276 DISCOVERY REPORTS 



200 m. long, being so disposed on it that the uppermost (the N70B) was fishing no more than 2 m. 

 above the other. In other words they were so arranged that they must have been sampUng virtually, 

 yet not quite, the same water. 



3000 



I 



4000 



1 



NUMBERS DAY 



5000 6000 



8000 



. I 



(6520) 



AVERAGE NUMBERS NIGHT 

 3000 4000 5000 6000 



(6920) 



(50) 



Fig. 63. Day and night vertical distribution of the staple whale food with the results presented in Fig. 17 expressed on 

 a true depth scale as area histograms, figures in brackets showing the average numbers of krill at each 40 and 50 m. depth 

 interval below 10 m. For further explanation see text. 



The average gatherings for 80 such paired night hauls and 68 paired day hauls are tabulated below.^ 



Paired oblique hauls in the surface {100-0 m.) layer 



Average catch night Average catch day 



NiooB N70B NiooB N70B 



38 29 20 4 



These figures are instructive. They show, for instance, the lesser catching capacity of the small 



N70B vis a vis that of the larger NiooB. They show too, however, that the N70B is manifestly 



^ Since the majority of the paired samples examined come from the krill-poor West Wind drift the averages it will be seen 

 are low. 



