CONTENTS 



Introduction page 193 



Acknowledgements 194 



Material 194 



Methods 196 



Seasonal variation in the vertical distribution of the standing crop 



of zooplankton 200 



Description of the observations 



The meridian of o°, 1938-39 season ....... 201 



The meridian of 20 E, 1938-39 season 201 



The meridian of 8o° W, 1933-34 season ... ... 204 



Observations in 0°, 20° E, and 8o c W in other years .... 205 



Observations in other areas — 20° W, no E and 160 E . . . 207 



The meridian of 90 E, 1951 207 



Average monthly variations in the sub-Antarctic and Antarctic . . . 209 



Regional variations in the standing crop of zooplankton . . . 213 



Variations with latitude and temperature 213 



Circumpolar variations within the Antarctic zone ..... 220 



Comparison with the findings of other workers 223 



Summary 227 



References 227 



Appendix 229 



