1898-1902. No. 21.] LICHENS. fi 



as a rule. Therefore we find them near mosses or actually growing- 

 over them. I would like to state that the fruticulose lichens are not 

 represented by many species in arctic regions but that they cover a very 

 extensive area and thus form a very important feature in the vegetation. 

 I cannot say how important they are to the animals of those parts of 

 the world. FRIES mentions, on the authority of Capt. FIELDEN that the 

 musk-ox at any rate never feeds on lichens at all. 



In some places we get the bare earth covered by crustaceous lichens 

 and a very common plant-society is represented by the species Lecanora 

 epibryon, Rinodina turfacca, Aspicilia verrucosa and one or two 

 other kinds. Pertusaria subobduceus is frequent on bare earth. 



Placodium splendens, one of the new species, growing over bare 

 soil must with its striking orange colour form quite a conspicuous ob- 

 ject in the landscape. It shows at any rate that lichens in the arctic 

 area are in a healthy condition and that for them the conditions are 

 not all adverse. Very noticeable is the absence from the "Fram"-ma- 

 terial of the reindeermoss, but its absence is also commented upon by 

 FRIES in his account of the lichens of the English Polar Expedition. 



When we turn to the lichens growing on stones we again find that 

 the cold of the north has no deterrent effect. Almost every stone which 

 is exposed for atleast part of the time has its coat of lichens. Species 

 of Gyroplwra are of frequent occurrence and they are often found 

 together with Parmelia lanat, one of the commonest of arctic rock- 

 lichees. We very commonly find Rliizocarpon geographicum and ge- 

 mitiatuin associated with Sporastatia testudinea. The intervals between 

 the larger crustaceous lichens being covered more or less by numerous 

 other kinds, amongst which some of the species of Aspicilia are often 

 met with. From what I have seen of Placodium elegans I would say 

 that this plant is a rapid grower comparatively speaking. I say this 

 because it is so often found on stones which are otherwise bare. This 

 seems to indicate that this particular plant has established itself more 

 quickly than any other lichen. 



Among the larger fruticose lichens the occurrence of apotliecia is 

 very unusual, whereas these organs of reproduction are of common oc- 

 currence with the simpler crustaceous lichens. The soredia do not play 

 any part in the distribution of lichens in the arctic region. Vegetative 

 reproduction of the very simplest kind seems to be the chief method by 

 which the larger lichens increase in number. 



