I02 /. G. ANDERSSON 



of the rock-surface, no moraines, and some very characteristic relief 

 forms are directly incompatible with the hypothesis of an earlier 

 ice-action upon the islands. 



But, on the other hand, it seems impossible that the^great wave 

 of cold, which has set its mark so severely upon the surrounding 

 lands, should have left no traces on the Falkland Islands. Nothing 

 is then more natural than the presumption that the birth of the 

 stone-rivers is a facies of the ice age of the southern lands. In 

 the Falkland Islands the climatic depression was not severe enough 

 to cause a glaciation, but only an intensive frost- weathering and 

 flowing slopes, quite as today in Bear Island we have no glaciers, 

 but only a marked solifluction. 



The stone-rivers certainly are the most striking feature of the 

 inland scenery in the Falkland Islands. Never did I feel them 

 more imposing than in a voyage along the southern coast of East 

 Falkland. Then, behind the lowland forming the south part of 

 the island, I saw in the distance the Wickham Heights, the principal 

 watershed, in its full extent. Every transverse valley of the low 

 mountain range was filled by the gray mass of a stone-river extend- 

 ing to or upon the lowland at the mountain's foot. The resem- 

 blance to a region crowded by valley glaciers was really amazing. 



The unsurpassed grandeur of the Falkland stone-rivers was 

 sufficient to provoke the idea that in this island group the solifluc- 

 tion has been at work on a larger scale than anywhere else on the 

 present earth surface. But I think that this effect of the solifluction, 

 that we meet with in the stone- runs, is rather exceptional, depend- 

 ing upon the petrological character of the rock yielding the material 

 to them. 



As already cited, Sir Wyville Thomson has clearly described 

 how the mountain ridges, from which the stone-rivers flow, consist 

 of hard, thick quartzite-bluffs, with intercalations of more soft 

 material. The last-mentioned softer bands are successfully at- 

 tacked by the weathering and turned into a muddy mass forming 

 the matrix of mud-streams. The quartzite bluffs, thus deprived 

 of their footing, break down in big blocks, and these are carried 

 down-hill by the mud-streams. In the bottom of the valley the 

 fine material is removed by running water, and there is left a very 



