UNEVENNESS OF OCEANIC PLANKTON 517 



Salpa, is found over half the region of the patch. Whilst the numbers of Sapphirina are 

 too small to be of much significance they may suggest that the Salpa patch is being in- 

 vaded by the copepod from one side. Fig. 3 shows their distribution together with that 

 of other Copepoda and Chaetognatha. 



Globigerina, small Medusae, Diphyidae, Polychaeta, Ostracoda, Amphipoda, decapod 

 larvae and young Euphausiacea occurred in isolated ones and twos along the roll. 



Record 3 



Date: 9. xii. 25. 



Time: 0900-1815. 



Position: 31 12' 35" S, 8° 00' 30" W to 31 45' 00" S, 7 10' 30" W. 



Distance by ship's log, 50-6 miles. 



The plankton was again poor, but the record showed an interesting change in com- 

 position at sections 14-15 as if passing from one hydrological zone to another. Doliolum 



DOL/OLUM 



10 15 



RECORDER SECTIONS 



Fig. 4. Variations in the numbers of the predominant plankton organisms on Record 3, taken over a distance 

 of 50-6 miles. Note the changes in the plankton community about recorder sections 13-15. 



the gastropod lanthina, and the copepod Candacia ethiopica all came to an end together 

 and Calanus robustior appeared on the roll. Their distribution, together with that of other 

 Copepoda and young Euphausiacea, is shown in Fig. 4. Diphyidae, Polychaeta, 



