334 Tra72sactious. 



rounding the slioulder of a spur, or in the wider part of a valley, where in 

 some corner or indentation in the side they have not been exposed to the 

 full action of denuding and transporting agents. They sometimes occur 

 near the mouth of tributary streams coming into a larger valley. These 

 moraines are at times the terminals of the tributary glaciers, but in some 

 cases they are undoubted lateral moraines of the main glacier. The 

 incoming stream of ice has pushed the main glacier over, and accumu- 

 lations have taken place on both sides of the tributary, especially on its 

 upper side, and the stream of water which has succeeded the glacier has 

 pushed over the main river in its turn, thus preserving the moraines at that 

 spot, even if they have been removed from other parts of the valley by the 

 transporting action of the river. 



A peculiarity may sometimes be observed in the arrangement of the 

 blocks of the lateral moraines which is occasionally useful for differentiating 

 them from terminal moraines. In the latter case there is no order or 

 arrangement — the blocks lie quite at haphazard ; but in the case of lateral 

 moraines the blocks usually lie with their long axes parallel to the direction 

 of motion, and also the upper ones overlap the lower ones like pebbles in a 

 stream. This arrangement is certainly rude at times, but it is quite dis- 

 tinct, and is brought about by the movement of the glacier causing a drag 

 on the heavy accumulations between it and the valley-sides where the 

 latter are not in close contact with the ice, such as at those parts where the 

 valley is slightly wider, or where the glacier is showing signs of decreasing 

 activity near its termirml face. 



Thin coatings of moraine also lie on the tops of truncated and semi- 

 truncated spurs left by the receding tide of ice. An excellent example of 

 this occurs on the downs behind Prospect Hill, in the angle between the 

 Kakaia and the Lake Stream (Plate V, fig. 2). 



(c.) Ice-flaned Slopes. 

 These are a special feature of the Lake Heron Valley, all the north-west side 

 of which is smoothed and terraced to a remarkable extent (Plate V, fig. 1), 

 recalling the photographs which appear in Professor Park's bulletin on the 

 Wakatipu district. The similarity of the landscape in the two districts is 

 really surprising. Judging from the shape and slope of the glacier-shelves, 

 the ice must have come from the north, even in that part of the valley ad- 

 jacent to the Rakaia. This undoubtedly proves that a section of the Great 

 Rakaia Glacier overflowed from the present Rakaia basin, came up the 

 valley of the Lake Stream, and left its marks on the ice-planed hills towards 

 Hakatere. As it overflowed the Clent Hills towards the Stour River it 

 modified the landscape similarly. 



(d.) Roches Moulonnees. 

 Ice-shorn rocks are a feature of certain parts of the land-surface. They 

 occur in the Lake Heron Valley between the Clent Hills Station and Lake 

 Heron, where their long scour slopes presented towards the north clearly 

 indicate the direction from which the ice has come. In the Rakaia they 

 appear at the sides of the river-beds, but lower down Ave find Double Hill 

 and Little Double Hill, typical roehes mmitonnees, in the actual floor of the 

 valley. In the Rangitata, the Jumped-up Downs, and the isolated hills 

 in the floor of the valley between them and the Potts are also excellent 

 examples of this result of glaciation. Clearly marked striae are rarely 

 seen but if the surface coating of soil and debris Avere removed they 



