84 CARL H. LINDROTH 



were of quite subordinate importance as far as the land fauna is concerned. 

 Judging from its present distribution on the island, a single beetle species 

 (Notiop/uliis aquaticus L. ; a wing-dimorphic Carabid and the only, entirely or 

 partly, short-winged beetle of the Icelandic fauna that in Scandinavia reaches 

 the regio alpina superior) may be suggested as a hibernator in the north. 



At least during the Last Glaciation, there were apparently two different 

 kinds of refugia in Iceland: (1) northern refugia, both on the coast and in 

 isolated nunatak areas with Arctic and Subarctic conditions; (2) coastal 

 refugia in the south and southeast inhabited mainly by Boreo-Temperate 

 biota. 



It is quite possible that conditions have been similar during the Riss 

 Glaciation, but this cannot be inferred from the present species distribution. 

 Thus, from a purely biogeographical standpoint, the most satisfactory 

 explanation of the character of the biota on Iceland as well as on the other 

 North Atlantic islands would be: (1) a land connection that persisted into 

 Early Pleistocene; (2) survival of the main part of the now existing floras and 

 faunas on the isolated islands through the Riss and Wiirm Glacials. 



Finally, I would like to summarize what has been said above: 



1. Conditions of faunal and floral distribution in the North Atlantic area 

 are extraordinary, with European biota predominating in Iceland and reaching 

 Greenland, but completely blocked by Davis Strait. 



2. An extraordinary explanation is therefore called for: a former land 

 connection from the European mainland to Greenland. 



3. The fauna of the Atlantic islands gives the impression of youth since it 

 does not include any endemic species. It can hardly be regarded as directly 

 descended from Tertiary time, but it is thought to have immigrated in one of the 

 Interglacials and thereafter to have survived at least one Glaciation, probably 

 more, in situ on coastal refugia in Iceland, Greenland, and probably also in 

 the Faeroe Islands. 



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Arldt, T. (1917). Handbuch der Palaeographie. I, 1-3. Leipzig. 



Arndt, W. (1928). Der Siisswasserschwamm Heteroineyenia ryderi Potts. &c. Zool. 



Anzeiger 77, \56-l66. 

 AsKELSSON, J. (1960). Pliocene and Pleistocene fossiliferous deposits. Int. Geol. Congr. 



Exc. Guide A2 (Iceland), 28-32. 

 BocHER, T. W.. HoLMEN, K. and Jakobsen, K. (1957). Gronlands flora. Copenhagen. 

 Dahl, E. (1958). Amfiatlantiske planter. Problems of amphiatlantic plant distribution. 



Blyttia 16, 93-121. 

 EiNARSSON, Th. (1961). Pollenanalytische Untersuchungen zur spat- und postglazialen 



Klimageschichte Islands. Sonderveroff. Geol. Inst. Univ. Koln 6, 1-52. 

 HuLTEN, E. (1958). The amphiatlantic plants and their phytogeographical connections. 



Kgi Svemka Vetensk. Akad. Handl. IV, 7(1), 1-340. 

 JoNSSON. J. (1954). Outlines of the geology of the Hornafjordur region. Geogr. Ann. 36, 



146-161. 

 Larsson, S. G. (1959). Coleoptera 2. General remarks. Zool. of feel. HI. 46b. 1-85. 



