THE BRYOPHYTA OF ICELAND ,"),")! 



iSj Brynm Duvalii, Chiloscyphus polyanthus var. fragilis, Harpan- 

 thus Flotowiamis and Pellia Neesiana. 



1. Kaldalon, along the banks of a stream: Hypnum calli- 

 chroum, Sphagnum teres, Harpanthus Flotowiamis and Cephalo'ia 

 bicuspidata var. Lammersiana. 



8. Reykjavik, on ground over which water was flowing: 

 slightly inclined surface with streamlets. The banks of the streamlets 

 were fringed with Philonotis fontana, Mnibryum albicans var. gla- 

 cialis, Brynm ventricosum, B. Dnualii and Acrocladinm cuspidatum. 



9. Gnupsdalur (NW. Iceland), gravelly ground, over which 

 water w r as flowing, streamlets flowing down the sides of the valley: 

 Philonotis seriata, P. fontana , Dicranella squarrosa, Haplozia cordi- 

 folia, Chiloscyphus polyanthus var. fragilis, Scapania undulata and 

 S. paludosa. Haplozia formed large black or greenish-black, and 

 Scapania paludosa very large reddish-brown patches in the water, 

 which was a few centimetres deep. 



In North Iceland several species of Hypnum occurred abundantly 

 in gravelly soil over which water was flowing, and often formed pure 

 Hypneta. Especially do Hypnum exannulatum var. piirpurascens, 

 H. falcatum, H. decipiens and sometimes H. stramineum and H. sar- 

 mentosnm occur in such localities. 



The Bryophyte Vegetation on Muddy Soil near Springs (D\). 



The bright-green moss-carpet around and below the point of 

 issue of the springs described by Helgi Jonsson (1900, p. 24. 

 1895, p. 73) as moss bogs (Icelandic D\) are one of the most 

 frequently occurring and characteristic plant communities of the 

 Arctic and Sub-arctic regions. They were first mentioned by Gron- 

 lund (1877, p. 330) as mats of sapgreen mosses along small streams 

 on mountain sides, consisting of Bartramia fontana, Webera albi- 

 cans, Brachythecium rutabulum var. rivulare and Hypnum uncina- 

 tum , a. description which includes both the moss bogs and the 

 moss vegetation along smaller streams, which have also much in 

 common. 



Moss bogs develop in muddy soil, in all places where the 

 ground water emerges as springs. They occur both on mountain 

 slopes and at the bottom of valleys , occasionally also at higher 

 levels, on rocky flats, but they are especially numerous on the 

 lowest mountain slopes and in the flat boggy land below these 



