The Flora of Disko Island and Adjacent Coast of West Greenland. 19 



Nomenclature. As I have but a limited access to literature 

 here, especially to the older one, and none at all to any larger collec- 

 tions, I am absolutely debarred from having any independent opinion 

 as to the question of nomenclature. I have therefore largely made use 

 of the nomenclature of the following works: 



1) C. H. Ostenfeld: Flora arctica I. 1902 (NB! published before 

 the Yienna Rules of 1905). 



2) Diverse works by H.G. Simmons especially: The Vascular Piants 

 in the Flora of Ellesmereland 1906. Flowerimg Piants and 

 Ferns of North Western Greenland, 1909, and Survey of the 

 Plytogeography of the Arctic American Archipelage 1913. 



3) B. L. Robinson and M. L. Fernald: Handbook of Flowering 

 Piants and Ferns. (Gray's new Manual 7th edition 1908). 



4) C. A. M. Lindman: Svensk Fanerogamflora Stockholm 1918. 



The distribution of the piants: This section is written by 

 Erling Porsild, revised and finally prepared for publication by M. P. 

 Porsild. Besides literature, our own collections and our excursion 

 diaries have been resorted to, which especially contain information 

 about the occurrence of the species common to the region concerned. 

 As to rarer species we have mentioned the name of the finder, but in 

 those cases when the species is fairly common we have omitted this 

 and replaced it by our general indications of frequency. Our special 

 aim has been to state, with greater accuracy than that used in Lange's 

 Conspectus Fl. Grl., the character of the natural habitats of the piants. 

 We have especially proceeded on the hnes laid down by L. Kolderup 

 Rosenvinge in „Andet Tillæg" and by N. Hartz in .,Fanerogamer og 

 Karkryptogamer fra Nordøstgrønland". 



The vertical distribution we have tried to exprcss in general 



remarks, having dispensed with statements of the actual numbers in 



hånd. In faet they seem to us still far too few and casual and 



hardly entitled to be published. Generally we think that a true 



arctic plant, what we in the following call a northern or widely 



distributed type, has no limit of elevation upwards, but on 



the other hånd, it frequently has a limit of elevation downwards 



near the southcrn limit of ils horizontal distribution, which, of 



c ourse, does not prevent it from occurring occasionally below its 



c ontinuous distribution, especially in piaces where fresh moraine ad- 



vances far down in the lowland, or where rivers and mountain streams 



may carry it right down to the coast. The absence of certain arctic 



s pecies in the lowland are hardly due to climatic conditions, the cause 



b eing the competition between the species. 



Far otherwise the piants whirh we denote as southern types. 



2* 



