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TYGE W. BOCHER 



southerly direction. Mapping of the species involved showed that in west 

 Greenland they behaved similarly, but at the same time it became clear that 

 full understanding of the nature of the boundary in east Greenland and a 

 corresponding one in west Greenland could not be obtained until the inland 



Fig. 1. On the left: floristic provinces and districts of Greenland. On the right: 

 frequencies of western and eastern species indicated as per cent of the total native 

 flora of each district. The first figure indicates western, the second figure eastern 

 species. (From Bocher, Holmen and Jakobsen 1959.) 



areas of middle west Greenland had been explored adequately and until the 

 world ranges of the species were better known. Now both requirements are 

 fulfilled. The interior of west Greenland has been studied during several 

 expeditions and the world ranges of the Greenland plants are now well 

 illustrated, thanks to the works of Hulten (1950, 1958), Porsild (1955, 1957) 

 Raup (1947), Tolmachev (1960) and others. 



Unglaciated middle west Greenland, which is broad enough to include 

 areas of continental and maritime cHmatic types, is particularly well suited to 

 phytogeographical studies. In fact, the detailed treatment of its flora gives us 

 one key to a main phytogeographical division of the North Atlantic area. 



Climatic curves for precipitation and annual temperature range bend from 

 the interior of southwest Greenland towards the northwest and sooner or 



