THE NEW ZEALAND SOUND BASINS 



27 



Harrison Cove streams.. The mountains composing the sides of the 

 valleys of the Wakatipu and Milford Sound types, may be notched 

 and broken by deep ravines reaching down to the water's edge; they 

 may appear even as isolated bee-hive and sitting-lion shapes; yet 

 their immense bases almost uniformly preserve a wonderful align- 

 ment. 



4. Truncation 0} spurs. — All stages in apparent truncation of 



Fig. 3. — Sketch of Sterling Falls, 504 feet high. (From a photo.) Note the 

 ahgnment of the canyon walls, and the steepness and evenness of the hanging valley- 

 walls. 



spurs may be found in the sounds and side canyons. The idea sug- 

 gested from a study of these forms is that of a former series of over- 

 lapping spurs which have been subjected to some mighty force, 

 whose maximum strength had been exerted along the lower and 

 central valley channels, causing the planing off of spur ends in some 

 cases, and utter shriveling up of spurs against the canyon walls in 

 others. The more complete truncation of spurs would, of course, 

 result in more perfect alignment of cliff bases. 



Examples of these progressive stages in apparent spur truncation 

 are shown by Figs. 7, 8, 9, and 6. 



