. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. MICROPLANKTON 239 ward ends of each series of observations. Chaetocerids were by far the most important group, as can be seen from the way in which their group-totals follow closely in parallel with the figures for total diatoms. Inshore they were represented by the usual rich variety of species, mainly neritic but some with panthalassic tendencies. Offshore there was some apparent overspill of the most abundant inshore forms, but the more definitely oceanic members of the genus, such as Chaetoc
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. MICROPLANKTON 239 ward ends of each series of observations. Chaetocerids were by far the most important group, as can be seen from the way in which their group-totals follow closely in parallel with the figures for total diatoms. Inshore they were represented by the usual rich variety of species, mainly neritic but some with panthalassic tendencies. Offshore there was some apparent overspill of the most abundant inshore forms, but the more definitely oceanic members of the genus, such as Chaetoceros convolution and C. peruvianum, were relatively much more important in the very poor phy toplankton met with there. The estimated totals for other groups was also greatest inshore, but the relative importance of those with offshore representatives was much greater near the shelf-edge and beyond. The Discineae were represented mainly by Thalassiosira spp. Of these T. hyalinum, T. rotula and the panthalassic T. subtilis were commonest inshore; T. excentrica and T. subtilis (again!) offshore. The oceanic Planktoniella sol was of some relative importance in one extremely small sample from near the outer end of the southern intermediate line. W5I002 WSIOOI WSIOOO WS999 WS998 WS997 WS996 -iO TOTAL DIATOMS CHAETOCERACEAE "PENNATAE" BIDDULPHIINEAE. -IO SO IOO SEA MILES FROM LAND Fig. 76. Estimated total diatoms, and diatom group totals, survey I, Orange river line, 12-14 March 1950. The Biddulphiineae were almost entirely confined to the inshore stations on both series, though Eucampia zoodiacns was recorded in very small numbers from station WS 986, at the seaward end of the Sylvia Hill line. This same species accounted for most of the inshore totals for the group, as we had found farther north at this season, but here there was a small proportion of Cerataulina pelagica in addition. Soleniineae formed only a small proportion of these samples. The higher numbers at three
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