1000 



branches spreading amongst the inosses (Loiseleuria, Galium saxa- 

 tile, Sibbaldia, Empetriim, Thijmns). 



Most of the species flower and fruit abundantly. Some which 

 do so only to a limited extent (see p. 916) are capable of propagat- 

 ing vegetatively, e. g. Pyrola minor, both Vaccinium spp. and those 

 species which form bulbils (see p. 909). Empetriim seems to fruit 

 sparingly. 



The mosses include several species which belong almost ex- 

 clusively to the Grimmia-heath, where hidden in the protecting 

 carpets of Grimmia hypnoides and G. ericoides even the more deli- 

 cate forms can grow, e. g. Jiingermannia orcadensis, J. Floerkii, 

 Gymnocybe turgida, Dicraniim arcticum, etc. A more detailed treat- 

 ment of the mosses is not possible from my own notes, and the 

 reader is referred to C. Jensen's paper (1897) which contains lists 

 of the mosses in the Grimmia-heath from the following localities: 

 Slattaratindur (p. 173), Kleivan (p. 181), and Skjællingfjæld (p. 185). 



Lichens are not represented by many species, and yet they 

 are more conspicuous in the Grimmia-heath and its transition to- 

 wards the grass-moor, than in any other formation, except the 

 lithophyte formation. Lar^e fructicose hchens are the most pro- 

 minent: Cladonia rangiferina a. o. Cladonia spp., Cetraria islandica, 

 Sphaerophon fragile, Cornicularia aculeata and Thamnolia uermicii- 

 laris; this last species is restricted to the mountain-summits, but 

 the others also occur frequently in the lower region. 



Transition from Grimmia-heath to grass-moor. This 

 is much more widely distributed than the typical Grimmia-heath, 

 and is brietly referred to under the name »Grimmia-Nardus forma- 

 tion« in several piaces in my preliminary paper (Ostenfeld 1901). 

 This transition formation is met with, as already stated (p. 953), 

 on flat or slightly sloping areas at altitudes from about 200 to 400 

 m. above the sea. At lower elevations the grass-moor appears in 

 its typical form with a decided predominance of phanerogams, 

 especially Nardns; in the higher region, Grimmia and its associate 

 mosses take complete possession. The midway stage between these 

 two extremes is what I call »//je transition formation« (the 

 Grimmia-grass-moor formation). In its adjustment to external 

 conditions and its dependence on them, this formation is naturally 

 intermediate between the grass-moor and the Grimmia-heath. The 

 soil is more »moory« than the gravelly substratum of the Grimmia- 



