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regard to the fish-fauna may trace a similar distinction between a 

 «southern» and a «northern» East-Greenland. The cause of this 

 must essentially be looked for in hydrographical conditions. 

 The warm Atlantic water flows northwards along the west-coast 

 of Iceland and forms the so-called Irminger-Stream. At the 

 north-west coast of Iceland and the submarine ridge, which 

 extends to Greenland in north-western direction, the main part 

 of the warm water turns towards Greenland and flows south- 

 ward. The sea south of the ridge, the «Irminger- Sea», is thus 

 with regard to the hydrographical conditions to be reckoned to 

 the northern Atlantic: the temperature is proportionally high 

 and the salinity considerable. Along the southeast coast of Green- 

 land itself runs however the cold arctic stream from the north 

 and either drives the warm water away from the coast or overflows 

 this^). For this reason the difference between the two faunas 

 is not so conspicuous at the Greenland coast as it is out in 

 the Denmark-Strait, when we compare the fauna south of the 

 ridge with that north of the ridge. With regard to the fishes 

 I have more minutely pointed this out in the just cited treatise; 

 with regard to the molluscs I shall have to postpone this till 

 my future account of this animal-group will appear in the report 

 of the Danish Ingolf-Expedition. 



Though the typical high-arctic species are wanting at Ang- 

 magsalik this territory shows yet in other ways the character of 

 being a transitional area, as several species with the same ap- 

 pearance as in the arctic seas occur in the littoral belt together 

 with boreo-arctic forms as Mytilus edidis, Cardium elegantulum 



It is highly deplorable that the bottom -temperature was not taken in 

 the places where dredgings or trawlings were undertaken. We should 

 otherwise have possessed a series of observations from the East-Green- 

 land coast which would have been of great importance for the de- 

 termination of the temperature's influence on the distribution of the 

 species. As a preliminary investigation measurements of temperature 

 are just as important as for instance determinations of the depths, 

 especially in such remote regions which are only visited by scientific 

 expeditions. 



