RECENT DISCOVERIES IN THE SOUTH NORWEGIAN FLORA 255 



with no trace of accompanying calciphilous plant species. Ranakollen is 

 strongly humified above the timberline and has a very trivial vegetation; all 

 we found were a few specimens of Carex rupestris along some rills and in a 

 few rocky cracks a little of Saxifraga oppositifoUa. 



The occurrence of Rhododendron lapponicum on Ranakollen must be 

 interpreted as a typically relict habitat — the plant literally "hangs on by its 

 fingernails" to the very rim of an acid humus surface. Since in Vaga and 

 Lorn as well as in northern Scandinavia this species is confined to calcareous 



Fig. 9. Trolltindene in Romsdalen, seen from Storgravbotn. Norwegian botanists 

 interpret these geological formations as "nunataks""; Norwegian geologists prefer 



another explanation. 



rock, it is impossible to interpret its occurrence in western Lesja as a result 

 of recent, or even Sub-Atlantic, dispersal westwards from an inland locality 

 farther east. Personally, I am convinced that some energetic field botanist may 

 succeed in finding more Rhododendron lapponicum (Fig. 1 1) still farther out 

 towards the coast, especially if he decides to use a "fine toothed comb" on 

 the mountains between western Lesja and Tafjord in south More. In the 

 1890's a comparatively rich mountain flora was discovered there in several 

 localities. As Rhododendron lapponicum flowers early and is easily over- 

 looked in its depauperate form during July and August, the species could 

 possibly have been missed on the said mountains by collectors. 



The results of my investigations in western Lesja are, thus, the following : 

 from one or more refugia along the coast of Romsdal — More, Rhododendron 

 lapponicum has dispersed inland during the deglaciation and arrived in an 



