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.lOHS. SCHMIDT 



made two cruises to ami from Iceland and the Fœroes following approximately the 1000- 

 meter line, then sailed southwards west of the British Isles to the Bay of Biscay, was 

 thus specially well suited to give light on these conditions, as I have endeavoured to 

 delineate on the accompanying Chart fig. 15. The shaded lines (single or double) on this 

 Chart represent the regions where the Salps occurred. 



As will be seen, up to the end of May the Salps were limited to the Atlantic, where 

 the northern boundary was found on the "Thor's" voyage southwards to lie to the west of 

 the Hebrides ', and absolutely none 

 were found in the Norwegian Sea or 

 North Sea. Towards the end of July 

 the conditions had quite changed , a 

 fact of which I was able to convince 

 myself on a cruise from Scotland to 

 Bergen and from Bergen to the Shet- 

 lands, the Fœvoes and Iceland. From 

 the Chart, on which the places where 

 we found the Salps are marked by 

 black spots, we see how the northern 

 boundary has moved to the east and 

 north. Thus a large tongue of the 

 Salps had pushed its way north of 

 the British Isles in a north-easterly 

 direction far towards the Norwegian 

 coast and in a northerly direction we 

 see now that the Salps reached as 

 far as north-west of the Faeroes. And 

 it was not a matter of small quan- 

 tities. Thus at our station (St. 121, 

 1905) north of the Shetlands we took 

 many hundred liters per half hour's 

 haul, and in the quiet calm weather 

 we could see under the clear surface 

 how the water was quite thick with 

 the Salps which occurred here and, it is 

 to be remarked, over small depths (less 

 than 200 meters) along with other di- 

 stinctly Atlantic oceanic forms, in 



almost as large quantities as we had found them anywhere even in the Atlantic over deep 

 water where they really belong. At the end of August when the "Thor" was coming 

 southwards from Iceland, the northern boundary had moved somewhat yet not very much. 

 We see also that the S. E. boundary in the North Sea had spread out further corresponding 



' In May and June we also found the Salps in large quantities everywhere beyond or near to the 

 lOOO-meter line west of the British Isles, as far south as the shading shown on the Chart, but south of 

 Ireland and in the northern part of Bay of Biscay where we had our southernmost station in 1905 none 

 were found iu June, neither bej'ond nor within the lOOO-meter line, as the Chart shows. 



Fig. 15. Drift of Salps (Salpa fusiformia) ,in 1905. The 

 shaded regions indicate where the Salps occurred in May 

 —July 1905 according to the investigations of the "Thor". 

 In May the northern and eastern limits lay west of Scot- 

 land , but in July they had moved far to the north and 

 east and in August still further. 



