PHYTOGEOGRAPHY OF GREENLAND 



287 



later reach the coast. Those expressing a high degree of oceanity veer away 

 from the land in south Greenland where a species like Jiincits squarrosus is 

 present. Curves for a lesser degree of oceanity leave Greenland in middle 

 west Greenland, but the northernmost ones cut off south Disko or penetrate 

 into Disko Bay, reaching the mainland at Jacobshavn and Sargag. 



48° 



Fig. 2. On the left: eastern limits in middle west Greenland for southern species 

 requiring humidity. On the right: percentage occurrence of Continental species 

 (black), Oceanic-sylvicolous species (dotted), and arctic species (cross-hatched). 

 Lines connecting 25 per cent Oceanic-sylvicolous and 25 per cent Continental 

 species. (From Bocher, 1963.) 



It has been shown that the majority of southern species follow the oceanity 

 curves. This means that most such taxa in Greenland have high humidity, 

 much snow, and perhaps high winter temperature as their main requirements. 

 They are not primarily dependent on high summer temperatures. This fact 

 may be of great importance in the discussion of their survival in Greenland 

 during the Last Glaciation. Fig. 2 on the left shows the position of the 

 eastern limits of such species in middle west Greenland. Line No. 4 indicates 

 the limit for many species, e.g. Thymus dnicei, Alchemilla alpina, A.filicauUs, 

 Hieracium hyparcticum, H. sect, foliolosa, whereas No. 10 delimits another 

 large group, e.g. Polyslichum louchitis, Leuchorchis albida. Phleum cowmiita- 

 limi, and St ell aria calvcantha. 



