Bd. III: 2) CONTRIBUTIONS TO THE GEOLOGY OF THE FALKLAND ISLANDS. 25 
In West Falkland I observed many stone-rivers round Port Albemarle and Port 
Stephens, several of them descending to the sea-level. Not far from the NW. arm 
of Port Albemarle I saw a singular specimen: a conical mountain, the top of which 
is completely (at least on the side that I saw) covered by a grey stoneriver-mass. 
In order to gain a more intimate understanding of the mode of formation 
of the stone-runs I determined to undertake a detailed survey of one of them, and 
for several reasons I elected the same very big stone-run situated south of Ber- 
keley Sound that was so lucidly described by Darwin. In his narrative the place 
is mentioned only as »the great valley of fragments»; an old Scottish shepherd, 
who at the time of my visit lived at Port Louis, named with rustic humour this 
vast and almost impassable accumulation of millions of huge quartzite-blocks »Prin- 
ces’ Street». On entering into a detailed discussion of the nature and origin of the 
Falkland stone-rivers it will be found necessary, I think, to give special names to 
the more important of them, and as a beginning I have named the large stone-run 
surveyed by me The Darzvin-stoneriver, this name including not only the continuous 
block-field in the bottom of the valley on the north side of Mount Vernet but also 
the adjacent network of block-covered patches on the two valley-slopes. 
During my stay in Port Louis I went day after day, as soon as the weather 
was endurable, to this place in order to work out a map of the stone-river on the 
scale I : 20000. As it was in the midst of the winter, I had only short working 
days, and the survey made but slow progress. When at last I was obliged to re- 
move to Port Stanley the map was incomplete as to the northern valley-slope. In 
this unfinished state it is reproduced on PI. 8. From the spot marked 262 near 
the lower margin of the map was taken a photographical panorama PI. 9, that 
should be compared with the map. 
At the right margin of the panorama a branch of Port Salvador is seen; (an- 
other branch of the same big bay can be noticed indistinctly in the background^ 
extending far inland). On the left part of the picture rises the rounded quartzite- 
hill Mount Vernet, in the front of which we see the valley that is covered by the 
stone-river. As seen on the map, the continuous block-field extends in the valley- 
bottom for a distance of 4,8 km. The panorama as well as the map clearly demon- 
strates that the slope of Mount Vernet forms a net-work of bare block-patches sur- 
rounded by grassy ground. This network-like type of stone-river is spendidly devel- 
oped on the mountain-slopes E. from Mount Vernet. In fact, the appearance of these 
.slopes strongly suggests the idea of a semi-fluid mass slowly flowing down-hill. 
A stoneriver-network covers also the northern slope rising to the quartzite-ridge 
from where the panorama was taken. Only on a small part of this slope is the 
network worked out on the map (between the figures 141 — 153 — 185) but this part 
is representative for all the northern slope. 
Schwedische Südpolar-Expedition igoi — igoj. 
4 
