348 DISCOVERY REPORTS 



Stations near South Georgia (Sts. 1127 and 1131). At St. 1125, farther west near the 

 convergence, the population was in stages iv, v and vi, together with some stage iii. 

 At this station the aduh females (see p. 318) were mostly unripe or maturing, 

 and this population had evidently been spawned during the current summer. The 

 average temperature at St. 1 125 was 3*19° C, and the population in that area must have 

 drifted from some position in the eastern Drake Passage or western Scotia Sea to the 

 south-west. The spawning which, earlier in the summer, gave rise to the stock at this 

 station must, therefore, have taken place in water having an average temperature 

 probably lower than 3-0° C. but higher than i-o° C. (Fig. 7). The population sampled at 

 Sts. 1 1 27 and 1131, however, consisting predominantly of stages iii and iv, must, from 

 its age, have been spawned later than that at St. 1125. It probably originated in the 

 western Scotia Sea in water having an average temperature considerably nearer the lower 

 limit of the optimum spawning range (i-o°C.) than that in which the population at 

 St. 1 125 originated. Thus, again, spawning took place later in the colder water. 



The stock sampled at St. 1125 (stages iv, v and vi) would appear to have been 

 spawned at about the same time as that which was sampled at Sts. 11 16 and 11 17 in 

 the Drake Passage (stages iv and v and v and vi respectively). The stock at Sts. 11 27 

 and 1 13 1, however (stages iii and iv), must have been spawned much later in the 

 season, so that a southward, and possibly eastward, movement of the spawning area 

 is discernible in the season 1932-3, as in the previous season, from the warmer to the 

 colder Antarctic surface water of the Drake Passage and Scotia Sea. 



The population at St. 1125 was older than that which was sampled at St. 830 in 

 the same position in the preceding February (cf. Figs. 24 and 28) since it contained 

 a higher proportion of adults and stage v and, taking both nets together, a smaller 

 proportion of stage iii. This again confirms the suggestion that the spawning occurred 

 earlier in the Bellingshausen Sea current in 1932-3 than in 1931-2. The stock at 1127 

 and 1 131, on the other hand, farther east near South Georgia, is of the same age as 

 that found in this region in February 1932 (St. 831 ; Fig. 24) so that these two popu- 

 lations, sampled in the South Georgia region at the same time in two succeeding 

 seasons, may be judged to have resulted from spawnings which took place in the 

 Scotia Sea at the same time of year in both seasons. In 193 1-2 it was seen that the 

 spawning east of South Georgia in the South Atlantic took place a good deal earlier 

 than that which gave rise to the population at 831. Thus in both seasons the spawning 

 seems to have moved southwards into the Scotia Sea from the South Atlantic and the 

 Drake Passage; but while the spawning in the Drake Passage, and probably in the 

 South Atlantic, took place earlier in 1932-3 than in 193 1-2, it seems to have occurred 

 at approximately the same time of year in both seasons in the Scotia Sea. 



On the sub-Antarctic side of the Antarctic convergence, between the Falklands and 

 South Georgia in February 1933, the two hauls large enough to be analysed, at Sts. 1 122 

 and 1 123, showed a population in stages iii, iv and v. The state of affairs at these two 

 stations was possibly the same as that at Sts. 828 and 829 in the previous season, and the 

 population sampled here may have been, perhaps, the product of a much reduced late 



