396 Geology of 



they form at the Makowiho Bluff the greatest portion of the 

 rnorainic accumulations. At this Bluff the blocks of rocks of which the 

 moraines are composed closely resemble in lithological character those 

 of which the circumvallations round Lake "Wanaka are formed. 

 Another interesting feature of the AEakowiko Bluff is the occurrence 

 of an ancient river bed, about fifty feet thick, deposited against a 

 lateral moraine, covered by younger morainic accumulations. A 

 further proof that oscillations in the position of the glaciers took 

 place also on the western side of the Alps, and that when advancing 

 again over a deposit of such comparatively incoherent nature, as a 

 gravel bed, the glaciers were doing so without destroying it to any 

 appreciable extent, we find in the valley of the "Waiau. The last 

 moraine reaching the sea-coast —as formed by the Parings glacier. 

 It is however greatly destroyed. 



The lowest signs of the Haast glacier were traced to about twelve 

 miles from the coast. I have not ascended the Arawata kio-h enough 



... o & 



to reach the ancient morainic accumulations in that river bed. Some 

 intelligent miners have however informed me, that deposits with laro-e 

 angular blocks are broken through by that river about ten miles above 

 its mouth. 



(C) The Foematiox or the Caxtebbuet Plaexs 

 This chapter would be incomplete were I not to offer a few notes on 

 the formation of the Canterbury plains, about which so much has 

 been written, and so many theories have been brought forward, that a 

 matter of apparently so much simplicity has in course of time become 

 quite obscured. Since my report on the formation of the Canterbury 

 plains was published iu 1S6-1, all the levels, surveys, engineering 

 works, together with well-sinking, have amply confirmed my views 

 that the Canterbury plains are of fiuviatile origin, that, with the 

 exception of some morainic accumulations in the upper portion and 

 the drift sands round Banks' Peninsula, and the partial lacustrine 

 deposits filling the former extension of Lake Ellesmere, the whole 

 of the plains were formed by the deposits of huge rivers issuing from 

 the frontal end of gigantic glaciers. Mr. J. T. Thomson, the 

 Surveyor- General, in a paper on u The Glacial Action and Terrace 

 Formation of South Xew Zealand,"' published in Yol. YI of " The 

 Transactions of the Xew Zealand Institute," gives a diagram in 

 illustration of the fan theory on page 329, and alludes to the sluice 



