DISTRIBUTION OF PHYTOPLANKTON 59 



abundant (1,176,000) at St. 161 far to the south-west of the island. It was present in 

 small numbers at Sts. 160, WS 67 and WS 68, between South Georgia and the Falkland 

 Islands, extending just across the Antarctic Convergence. Small numbers were also 

 taken on the C line in late May 1927. Another species of Fragilaria whose identity 

 was not determined was noted in small numbers at WS 35. 



Fig. 29. Distribution of Biddulphia striata round South Georgia in the December-January 1926-7 survey 



For full explanation see legend of Fig. 16. 



Synedra. 



Synedra spaihulata, Schimper, was met with at each side of the island but only in 

 small numbers. It was taken at the following stations: WS 36, WS 38, WS 39, WS 43, 

 WS44, WS45and WS 51. 



Thalassiothrix. 



Thalassiothrix antarctica, Schimper, was abundant at St. 12 on the line approaching 

 South Georgia from Tristan da Cunha in February 1926, where it was taken to the 

 number of 4,600,000 in the N 70 V net used from 50 m. to the surface. Between this 

 station and South Georgia the ' Discovery ' passed through a dense zone of this diatom 

 as revealed by the Continuous Plankton Recorder which was put into operation at 



