Geological Survey of Canterbury. 141 



roche moutonnee (skor) , of which the north-west face, which descends 

 slowly is rounded, worn down, and striated from the almost incon- 

 ceivable weight of a tremendous glacier, whilst its opposite face is 

 rough and very precipitous. The vegetation on it is very rich and 

 varied. Some enormous beech trees rose majestically over the dense 

 undergrowth of shrubs, consisting mostly of different species of 

 Coprosma, Olearia, Panax, Leptospermum, and many others, generally 

 found on the shores of our alpine lakes, not omitting the beautiful 

 rata (Metrosideros lucida), which grows in large groves, and when 

 in flower, must present a beautiful appearance. I was not a little 

 surprised to meet with the Weka (Ocydromus Australis) on this small 

 island ; it doubtless obtains ample nourishment from the berries of the 

 dense growth of shrubs and the insects which frequent them ; but it 

 is difficult to conceive how this bird, unable to fly, could reach this 

 solitary spot, nearly a mile from the nearest land. 



I devoted another day to an examination of the valley of the 

 Acheron and Lake Lyndon. Following the small valley north of 

 Barker Hill, I reached the former channel of the outlet to the lake, 

 now partly concealed under newer fluviatile deposits. In many 

 localities the remains of moraines, or rounded bosses of rock, stand 

 above these fluviatile beds, by travelling along which I reached the 

 banks of the Acheron, opposite the north-west slopes of the Thirteen- 

 mile-bush range. Descending five or six terraces for about 150 feet, 

 I crossed the river-bed and ascended to about an equal height on the 

 opposite side, where I reached the bridle-path leading to the "West 

 Coast road, which passes Lake Lyndon. Three miles from this lake 

 the path rises rapidly for about 300 feet on the slopes of a huge lateral 

 moraine, crossing the valley from side to side, through which the 

 principal branch of the Acheron, coming from Big Ben, has forced 

 its way. Numerous angular blocks lie here everywhere on the 

 summit ; and several small lagoons without outlet give also to these 

 beds the characteristics, peculiar to those glacier deposits. Behind 

 them, towards Lake Lyndon, the valley opens again and forms a 

 grassy flat, through which, near the moraine, the small creek, coming 

 in the direction of Lake Lyndon, has cut a deep channel, showing 

 in its banks that it is the former bed of a lake filled up with silt. 

 Before reaching Lake Lyndon, we pass a remnant of this former 

 lake, now mostly a large swamp. Behind it the valley still continues 

 of a considerable breadth, and the road leads among tufts of snow- 

 grass along the dry bed of a small water-course till we approach the 



