BY E. C. ANDREWS. 



809 



Such deeper basins occur at or near marked canon-convergences, 

 within walls of exceptional height and strength. Here, also, 

 occur the finest hanging valley types. Very little morainic 

 material is to be found in these steep canons. 



^-^^^?^sM:^<^^:!i=iL^s^^' 



Fig.5.— The Sentinel, Clinton Valley, N.Z., 3000 (?) feet above 

 valley. A truncated spur, the truncation causing the hanging valley 

 at A. 



If, now, these forms be compared with those of ordinary 

 stream-valleys, it will be seen that the cirques, lake- and sound- 

 basins, spurless walls and flattish floors are all Brobdingnagian 

 equivalents of the basins and narrows in the flood-channels of the 

 various stream-valley types. In the one case the flood-channel 

 occupies but a fraction of the valley, while in the other the 

 glacier, or ice-flood, occupied almost the whole of the canon. 

 This point, I think, has been especially emphasised by Prof. 

 W. M. Davis (9a,p.293). 



It is, however, when comparing glacial canons with the gutters 

 produced by floods along disused roads, that the great resemblance 

 to glaciated canons is noticeable. In both cases the flood 

 occupied either the whole or the greater portion of its valley. 



