608 



A. HESSKLBO 



stegium Sprucei fonned thin, dark-green coverings, and. where the 

 \vater flowed down the roof and walls Thamnium alopeciiriim oc- 

 curred as pure growths. 



A similar vegetation was found everywhere in clefts and caves, 

 and where the conditions pertaining to light and moisture werc 

 more yarying, the number of the species was still greater than in 

 the vegetation described above. This was for instance the case in 

 the deep and J)road Flokastadagil near Breidabolstadr. There, 

 on the damp walls, almost the same species were growing as in 



Fig. 33. Bryo.viphiiiin norvegicum on ono of the sitles of Flokastadagil. 



Bleiksågil. A high, dry, perpendicular rock-face was for a consi- 

 derable distance entirely covered with a shining, dark-green mat of 

 Bryoxiphium norvegicum (Fig. 33), which has hardly been found 

 elsewhere in such enormous quantities. In other piaces Grimmia 

 torqiiata covered the rock-sides and blocks with its irregulaiiy-rounded 

 cushions, and Hijpnum palustre was very common everywhere at 

 the water's edge. Neckera complanata was common in dry ditches. 

 At the side of a small waterfall, Klitnafoss, there was a rather 

 large cave, down one side of which some of the water from the 

 waterfall was running. There Thamnium alopeciirum grew abun- 

 danllj', while the drier walls of the cave were covered with Enrhijn- 

 chiiim Swartzii and Mniiim orthorrhyuchum. On the ground at the 



