THE BRYOPHYTA OF ICELAND 



567 



hanks of this brook and of the flat boggy surroundings (which are 

 partly influenced by the heat of the soil, partly inundated by the 

 hot water) is very luxuriant. Both around the basins of the springs 

 and along the brook formed by the outlets of the springs, grew a 





Fig. 21. Thorliikshver near Skalholt. In the background the river Biuart'i: behind 

 the fence to the left is a potato field, where the temperature of the ground was about 

 25. The chief outlet of the spring is just behind the small elevation to the left, and 

 the outlet-channel is from the right straight across the foreground. The ''peninsula", 

 in the middle of the figure, surrounded by the hot water, is partly covered with 

 Sphagnum (the light patch) and partly with //i/pm/m-mats (the dark patch). 



broad belt of enormous yellowish brown and pale-green Sphaynum- 

 cushions, 25 cm. deep, chiefly formed by S. imbricatiim (yellowish 

 brown), S. teres and S. cymbifolium (whitish green) interwoven with 

 Hypnum stramineum, Hijlocomium squarrosnm and here and there with 

 Acrocladium cnspidatiim, Hypnum imponens and H. Lindberyii. The 



