. ON ROLL MILLA6E| ^ HOUR 2310 0 SECTl0re|,l4|5|6|7|B|9||a|l||li;|l'lh4ll5ll6ll7|lBII9l?0|gllP;i23l24l25l?6l27l?8|a9|30|3l|3Z133; 10 20 30 40 50 , 60 , 70 34|3S|36|3713813914014) I42I43144I45I46I4/155I R0 90 100 110 03 04 05 06 13 oto IS DO 20 Fig. 144. Graphical representation of record obtained by the Continuous Plankton Recorder on approaching South Georgia from the north-east in February 1926. Whilst the record, which is reproduced in Fig. 144, shows that the dense zone was coming to an end, the fact that Thalassiothrix antarctica was taken in moderate numbers at one of the stations i
. ON ROLL MILLA6E| ^ HOUR 2310 0 SECTl0re|,l4|5|6|7|B|9||a|l||li;|l'lh4ll5ll6ll7|lBII9l?0|gllP;i23l24l25l?6l27l?8|a9|30|3l|3Z133; 10 20 30 40 50 , 60 , 70 34|3S|36|3713813914014) I42I43144I45I46I4/155I R0 90 100 110 03 04 05 06 13 oto IS DO 20 Fig. 144. Graphical representation of record obtained by the Continuous Plankton Recorder on approaching South Georgia from the north-east in February 1926. Whilst the record, which is reproduced in Fig. 144, shows that the dense zone was coming to an end, the fact that Thalassiothrix antarctica was taken in moderate numbers at one of the stations in the March-April survey (St. 41) shows that in March it was still in the area and not far from the island. Whilst there is little relevant evidence here except that there was no dense phytoplankton in the region of the Euphausian concentration, the possibility, in the light of what follows, that in March the zone of Thalassiothrix may have extended farther in towards the concentration of Euphausians against the coast may perhaps be kept in mind. The inverse correlation between the dense patch of Euphausian larvae and the gap in the Thalassiothrix on the record in Fig. 144 is of interest. We have seen in the 1926-7 South Georgia survey how closely the phosphate content of the water corresponded with the production of the phytoplankton. Their corre- spondence is shown in Figs. 38 and 39 and discussed in detail on pp. 79-84. In Fig. 145 the phytoplankton production in this survey is shown in a graph plotted against a scale of phosphate values, the phytoplankton values being averaged for the stations falling within each division of the phosphate scale. We have further seen how closely the whale distribution appears to be bound up with its food Euphausia superba. If there is an inverse correlationship between the distribution of the phytoplankton and Euphausia superba brought about either by the grazing or the exclusion of the latter, then, provided whales and Euphausians are prese
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