228 DISCOVERY REPORTS 



the Southern Oceans this distribution is very sparse and it will be of interest to note how future 

 collecting will contribute to our knowledge of the distribution of juvenile T. carpenteri. 



The original record of T. carpenteri (adult) was made by Quatrefages (1865) from 6o° 3' S., o° 6' E. 

 Since then the adult has frequently been reported from the Atlantic sector of the Antarctic. In earlier 

 Discovery reports Monro (1930, 1936) recorded it from South Georgia, the South Sandwich Islands 

 and numerous localities scattered throughout the area, and Hardy and Gunther (1935) also reported 

 it from South Georgia. The ' Norwegica ' collected the species near Bouvet Island and the South 

 Sandwich Islands (Stop-Bowitz, 1949) and the Swedish Antarctic Expedition collected it near the 

 South Orkneys (Stop-Bowitz, 1951). 



Tomopteris planktonis and Tomopteris septentrionalis 

 (Text-figs. 31-3, Appendices I and II) 

 T. planktonis and T. septentrionalis are the only known cosmopolitan tomopterids and have 

 been found in all explored water masses in the South Atlantic Ocean. T. planktonis (size range 

 2-10 mm.) was collected principally by the N 70 net but occurred also in all other nets except 

 the N 450. T. septentrionalis measures up to 15 mm. in length and was caught frequently by all 

 the nets. 



T. septentrionalis was caught more often by the larger nets than T. planktonis, therefore some points 

 about their distribution must be emphasized or they may be misinterpreted. In addition the larger 

 number of ' Tomopteris unidentifiable ' listed in Appendix I, which, as noted on p. 227 are probably 

 either T. planktonis or T. septentrionalis, must also be considered. 



(a) Around South Georgia both species were frequently taken in the Warm Deep Water, but a 

 few exceptions (five of T. planktonis and one of T. septentrionalis), together with the fourteen ' Tomo- 

 pteris unidentifiable ', were collected outside this water mass. Additional samples around South Georgia 

 may show either that both species inhabit Antarctic Surface Water and Warm Deep Water, or that 

 one of them inhabits the Warm Deep layer only. 



(b) In the vicinity of the Greenwich Meridian, T. septentrionalis was caught more often by the 

 N 100 B nets than T. planktonis which, however, appears to be equally well distributed there, because 

 it was caught more often by the N 70 V nets, which explored a greater depth range. 



(c) In the South Sandwich survey T. septentrionalis was collected fifty-five times, of which forty- 

 five were by the towed nets (Text-fig. 33), but T. planktonis was caught only on five occasions, of 

 which three were with towed nets (Text-fig. 31). T. septentrionalis is not necessarily more abundant 

 than T. planktonis in this region, but the type of net may not have been so favourable for catching the 

 latter species. 



Previous records. T. planktonis has been widely reported from the South Atlantic Ocean. In the 

 Antarctic Zone it was reported by Augener (1929) from the Weddell Sea, by Monro (1930, as T. 

 carpenteri) from St. SS 21, and by Stop-Bowitz (1949, 1951) from Bouvet Island, the South Sandwich 

 Islands and South Georgia. The records of T. planktonis in the present work appear to be the first 

 from the Sub-Antarctic Zone. In the Sub-Tropical and Tropical Zones, Apstein (1900) reported it 

 west and north of Ascension Island, and Monro (1936) from 'Discovery' stations between the Cape 

 Verde Islands and the Falkland Islands. 



T. septentrionalis was reported by Augener (1929) from the Weddell Sea, by Monro (1930) from 

 South Georgia and the South Sandwich Islands, by Hardy and Gunther (1935) from South Georgia, 

 by Monro (1936) from 'Discovery' stations scattered throughout the Antarctic Zone and by Stop- 

 Bowitz (1949, 1951) at numerous localities between io° E. and South Georgia. There appear to be 



