SEA-FISHERIES LABORATORY. 



339 



1909. 



Zone. 



Diatoms. 



Eino- 

 flagellates. 



Copepoda. 

 Adults. Nauplii. 



April 7 ... 



60-40 



10,525 



100 



10 



300 





40-20 



14,521 



130 



20 



320 



Hensen 



20-10 



14,235 



380 



26 



560 





60-0 



19,260 



365 



141 



720 



April 8 ... 



60-40 



12,475 



300 



35 



750 





40-20 



62,120 



1,500 



142 



3,600 



Hensen 



20-10 



20,420 



640 



91 



2,000 





60-0 



86,250 



1,600 



115 



4,900 



Aug. 6 ... 



60-40 



180 



230 



254 



410 





40-20 



100 



60 



195 



390 



Nansen 



20-10 



110 



10 



270 



1,140 





10-0 



80 



— 



291 



1,190 



Aug. 7 ... 



60-40 



35 



10 



116 



235 





40-20 



40 



5 



85 



50 



Nansen 



20-10 



50 



25 



32 



190 





10-0 



180 



30 



1,900 



480 



Aug. 10 ... 



60-40 



440 



30 



230 



440 





40-20 



545 



40 



282 



165 



Nansen 



20-10 



735 



40 



267 



570 





10-0 



120 



60 



1,928 



2,510 



On April 7th, in addition to a vertical haul from 

 bottom (60 faths.) to surface, hauls with .the Petersen- 

 Hensen closing net were taken through the zones 60-40, 

 40-20 and 20-10, but no vertical haul was taken in 

 10-0 faths. The figures show in every case some increase 

 in numbers in passing upwards towards the surface, and 

 the zone 20-10 contains the largest population. It will 

 be noticed that this zone is only 10 faths., half the extent 

 of haul in the two deeper zones. . 



On April 8th the hauls were the same, but the 

 highest numbers are now in the middle zone, 40-20 faths , 

 and next comes the upper zone. The lowest zone, as oxi 

 the previous day, contains least life. In August an 

 additional vertical haul through the most superficial 

 zone, 10-0 faths., was always taken. On August 6th the 

 plankton is fairly well distributed through the layers. 



