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STEINDOR STEINDORSSON 



have a very similar distribution, chiefly within the same districts and nunatak 

 areas. If these facts are taken into consideration, the accidental spread of the 

 species in the districts mentioned above is still more improbable. 



It would take too long to present a detailed description of the distribution of 

 all the centric species, but an example should be given: 



Papaver radicatum (Fig. 9) is one of the species, which is considered as a 

 survivor in Scandinavia. No other Icelandic plant seems to be so closely 

 connected to the probable refugia and nunataks as P. radicatum. Although 

 the Icelandic material of P. radicatum has been divided into some subspecies 

 and varieties, it will be treated here as a single species only. 



Fig. 9. Papaver radicatum. 



The chief center of the species is the Vestfirdir and Breidifjordur districts 

 together with their closest vicinities. Over the whole of the Vestfirdir district, 

 P. radicatum is very common in the lowlands. On the other hand, the species 

 is not found at higher altitudes on the slopes and mountains of that district. 

 Outside the Vestfirdir district the species grows almost exclusively in the 

 mountains, with the exception of the peninsula Vatnsnes where its habitats 

 are similar to those of the Vestfirdir district. 



In the Vestfirdir and Breidifjordur districts the distribution of P. radicatum 

 is almost continuous, but outside this center its spread is broken and the 

 species is found only in isolated mountains and mountain ranges, as far as 

 we know, both in north and west Iceland. In the Austfirdir district, on the 

 other hand, the distribution is more continuous, ahhough there seems to be a 

 gap in the central part of the district. Hardly any other Icelandic species shows 

 such distinct affinity to the possible refugium areas, since it is more or less 



