944 



degree the number capable of thriving under these conditions. The 

 most characteristic phanerogams (Montia, Epilohiiim alsinifolium, 

 Saxifraga stellaris, and Stellaria uliginosa) grow in the moss-cushions, 

 and their shoots ramifying in the mossy substratum, form more 

 or less dense swards. 



The Philonotis association has evidently a wide distribution in 

 northern mountainous countries. From my own observations, it 

 occurs in Greenland and especially in Iceland, and it is also re- 

 corded by authors who have described tlie vegetation of these re- 

 gions. E. Warming in his memoir on the vegetation of Greenland 

 (1888, p. 35) mentions a »Philonotis vegetation« which is identical 

 with what we are now describing. H. Jonsson in describing it 

 (1895, p. 73) from Iceland says: a moss-vegetation consisting of light 

 green, larger or smaller moss-cushions, resting on a muddy sub- 

 stratum (»Di«). The same author in more recent papers (1900, p. 

 25 and 1905, p. 11) refers again to this formation which he calls 

 moss-bog (»Moskær«), and characterises it by Philonotis fontana and 

 to some extent by Mniobryum (Pohlia) albicans, var. glacialis; the 

 phanerogams recorded by hini are almost identical with those given 

 liere for the Færoes. Similar in character is also the vegetation 

 surrounding the »warm« springs (»Unartut«) on Disco in Greenland, 

 as mentioned by Porsild (1902, p. 227). 



It is hardly correct, however, to group the Philonotis association 

 as Jonsson has done, with the moss-bogs (Moskær) described by 

 Warming (1888, p. 132). Warming's definition of a moss-bog 

 really amounts to this, that they are grass-bogs (Græskær) so over- 

 grown by mosses that the phanerogams have been displaced; it 

 foUows from this that one of the characteristics of a moss-bog is 

 the stagnant water (opposed to the Philonotis association). It is of 

 course the case that these two plant-associations are related, but 

 they are not identical. Kolderup Rosen vinge in his paper on 

 the vegetation of South-Greenland (1897, pp. 243—44) also included 

 both forms of vegetation in his term »Moskær«. On the other band 

 Porsild (1. c, p. 226 and 227) has distinguished them, but removes 

 them too far apart from one another. In my own opinion it seems 

 most natural to separate the two formations ; the fresh, running water 

 which presumably contains abundance of oxygen and carbonic acid 

 gas, with little humic acid, is extremely important for the Philonotis 

 association, and brings about the presence of some species while 

 suppressing others, which are common in a true bog-formation. 



