ICE AGE REFUGIA IN ICELAND 



307 



have been possibilities for ice-free nunataks during the glaciation. These 

 plant centers are as follows: (1) The Breidifjordur district, (2) The Vestfirdir 

 district, (3) The Eyjafjordur district, (4) The Austfirdir district, (5) The Myrdalur 

 district, (6) The Hvalfjordur district (Fig. 1 and Table 1). 



Fig. 1. Sketch map showing possible refugia areas (I-VI) and single nunataks 

 (1-13): I, the Vestfirdir district; II, the Breidifjordur district; III, the Eyjafjordur 

 district; IV, the Austfirdir district; V, the Mjrdalur district; VI, the Hvalfjordur 



district. 



When looking for possible survivors of the Ice Age, attention will first be 

 drawn to those species which have been established with certainty as survivors 

 in other northern countries. Of these, the plant group which has been charac- 

 terized as "West Arctic" species in Scandinavia, is the most remarkable. 



There is hardly any disagreement among Scandinavian plant-geographers 

 about the West Arctic plant group being a survivor of the Ice Age in Scandin- 

 avia, and that its plants have migrated from America to Europe at least before 

 the Last Glaciation. On the whole, 27 species have been classified with various 

 degree of certainty as West Arctic, and at the same time considered as over- 

 winterers in Scandinavia. Thirteen of these species are definitely found in 

 Iceland, and perhaps 2 more. In Scandinavia all the West Arctic species 

 are mountain plants. The same applies to the majority of the West Arctic 

 plants found in Iceland, as 8 of them have their main distribution above 

 300 m, and some of them are found growing up to 1000 m above sea-level. 



These 13 West Arctic species in Iceland are: Campanula uniflora, Carex 

 niacloviana, Carex nardina, Carex rufina, Cerastium Edmondstonii{C. arcticum), 

 Draba rupestris (D. norvegica), Epilobium lactiflorum, Erigeron unalaschkensis, 

 Euphrasia frigida, Festuca vivipara, Pedicularis flammea, Sagina caespitosa, 

 and Stellaria calycantha. 



When we observe the distribution of these 13 species, various peculiarities 



