SURVIVAL OF LICHENS DURING THE GLACIAL 

 AGE IN THE NORTH ATLANTIC BASIN 



Zdenek Cernohorsky 

 Botanical Institute, Charles University, Praha, Czechoslovakia 



There have been several students who have contributed to our knowledge of 

 the lichen flora of the North Atlantic basin. The greatest merits in this 

 respect go to the Scandinavian authors. Apart from monographs written on 

 some genera, collective pubUcations of the last 30 years are especially impor- 

 tant for our consideration (e.g. Dahl, 1950; Dahl, Lynge and Scholander, 

 1937; Lynge, 1928, 1934, 1937, 1938, 1940a; Lynge and Scholander, 1932). 

 As these pubUcations contain historical chapters as well, they reveal names of 

 men who, in the past, devoted their study to the exploration of the lichen flora 

 of the North Atlantic basin. 



Owing to these explorers we have nowadays quite a sound knowledge 

 concerning macrolichens and their distribution in the said space. This is 

 especially true of the conspicuous species, collected even by non-lichenologists. 

 As far as microlichens are concerned, their systematic study has only begun 

 (e.g. Lynge, 1940b). Furthermore, macrolichens in different regions are 

 treated variously. Apart from this, we are lacking in paleontological records 

 and this is the reason why I can contribute but partly to the solution of our 

 general problem. 



The knowledge of macroUchens led some authors to compare the lichen 

 flora of various parts of the North Atlantic basin. We must mention especiafly 

 the Norwegian lichenologist Lynge (1934, 1938, 1940a), who compared 

 macrolichen floras, e.g. in Iceland, northeast Greenland, Svalbard, and Novaya 

 Zemlya. He states that these islands have many species in common and that 

 their floras are like that of Scandinavia. He mentions also that the most 

 striking of these floras is that of Novaya Zemlya, due to the presence there of 

 several eastern species not found farther to the west. The microhchen species, 

 e.g. of the genus Rhizocarpon, indicate even greater diff'erences. 



The aforementioned similarity and the widening knowledge about distribu- 

 tion of the macrolichen species aroused among lichenologists a question 

 concerning the history of these North Atlantic species. It was again Lynge 

 who constantly approached this problem, and he had tried to summarize it 

 before his death (Lynge, 1938, 1939a). He ascertained that in Svalbard 

 (Spitsbergen and North East Land) grows a relatively considerable amount of 



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