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JO HS. SCHMIDT 



hydrographical boundary at the easternmost part of the south coast. A rise of temperature 

 on the north coast in the summer time can be seen distinctly from the average temp- 

 eratures for Grimsey given up on p. 115 and from the Charts figs. 6 and 8. 



It appears from what has been said that we may expect to find quite different con- 

 ditions on the different coasts of Iceland, and a confirmation of this is given by the 

 investigations on the spawning of the gadoids. I shall first of all describe the cold por- 

 tions of the Icelandic waters, namely the east and north coasts, which are not only totally 

 different from the other coasts but on the whole have quite a unique position 

 within the whole region investigated by me. 



Fig. 7. Observations of temperature during the third voyage of the "Thor" round Iceland in July 

 1904 (cf. Chart IX). See also explanation to fig. 5. 



A. The cold portions of the Icelandic waters (east and north coasts) 



At the time of year when most of the gadoids are spawning at Iceland, namely in 

 the months of March, April and May, the temperature of the water on the east and north 

 coasts is very low, ca. 0° — 3°, as the warm Atlantic water has not yet or only to a slight 

 extent reached these coasts. These low temperatures quite exclude all spawning of the 

 gadoids here, with exception of the arctic Gadussaïda. The cold portions of the Icelandic 

 waters may thus be characterized in contrast to every other part of the regions invest- 

 igated by the lack of production of gadoid fry with exception of the arctic Gadus 

 saïda, which for the rest only reproduces there in small quantity and perhaps only when 

 polar ice is present on these coasts. A small limitation to this statement is necessary 

 however, as there is a slight "after-spawning" of the cod {Gadus ccdlarias), the species of 



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