2 6 2 DISCOVERY REPORTS 



Station 2625 (41 497' S., 18 49-9' E.). Reference to the hydrological data for this station shows that 

 a northward extension of Subantarctic water was present between 50 and 100 m., and the net which 

 fished from 93 to o m. may well have taken the majority of the catch from this layer. Similar penetra- 

 tions below subtropical water are shown at Stations 1773 and 1774, and also at Station 2036 (Fig. 22). 

 It seemed possible that the penetration may be even farther north in the deeper waters, but examina- 

 tion of a line of 2 m. vertical nets in subtropical waters at Stations 675 (fishing depths 2750-2000, 

 2000-1500, 1 500-1000, and 1000-750 m.), 677 (fishing depths 2000-1 500, 1500-1000, 1000-750 m.) and 

 679 (fishing depths 2000-1500, 1500-1000, 1000-750 m.), has not revealed a single specimen, and it is 

 therefore very unlikely that tropical submergence takes place. A series of hauls from stations off the 

 limits of the chart shown in Fig. 17 have been examined for S. gazellae, and in all cases the results 

 have been negative. The stations were made in the Peru current, the Benguela current, and on the 

 meridian of 90 E. in the Indian Ocean. 



Table 12. A comparison of day and night vertical stations from various localities, and various months; 

 numbers corrected for a 250 m. haul; percentage is the number at a particular horizon to the total for 

 all depths 



The southern limit of distribution of the species is the Antarctic continent ; and although it has not 

 been possible owing to ice conditions to prove this in many areas, it can be said that where the 

 Antarctic coastal waters have been reached, S. gazellae has been found. Owing to peculiarities of its 

 life history (p. 270) it is improbable that it can breed in shallow shelf-waters, but even in the almost 

 uniformly shallow Ross Sea it occurs in small numbers. In this area it averaged seven specimens 

 per 20-minute haul in the month of January. In oceanic waters the average per 20-minute haul for 

 the month was 47-7. 



Discovery stations in the Weddell Sea have been infrequent, and were only made in the eastern end, 

 owing to the treacherous ice conditions often encountered in the area; but Bollmann (1934) reported 

 that the ' Deutschland ' found S. gazellae in the Weddell Sea. Unfortunately he gives little indication 

 of its frequency of occurrence. 



Previous work on the distribution of the species has been somewhat confused by the inclusion of 

 S. gazellae in the synonymy of S. lyra, and also by the existence of a form of S. lyra which closely 

 resembles S. gazellae. This has been discussed on pp. 245-254. 



Although S. gazellae was not described until 1909, there were several earlier records of 5. hexaptera 

 which have been attributed to the species. These are discussed by Ritter-Zahony (191 1). 



In his paper giving the original description of the species, Ritter-Zahony observes that although his 

 specimens came from the South Indian and South Pacific Oceans, the Berlin Museum possessed a 

 specimen from the Tonga islands; he does not refer to this specimen again, and, bearing in mind the 

 fact that he was unable to determine the shape of the fins in his alcohol-preserved specimens, it seems 



