Canterlury and Westland. 371 



CHAPTEE XV. 



THE GEEAT GLACIEE FORMATION. 



General Considerations. 



In treating of the Physical Geography of Canterbury, I have already 

 alluded to the Great Glacier period of New Zealand, as having played 

 such a conspicuous part in the latest history of the two provinces 

 under consideration, that its effects are manifest everywhere as soon 

 as the explorer advances towards the mountains. It would he beyond 

 the scope of this Eeport to give all the details collected by me during 

 the progress of the Geological Survey, on this interesting formation ; 

 the more so, as the principal results have already been laid before the 

 public in several publications. Of these, my Reports on the formation, 

 of the Canterbury plains, and on the head waters of the river Eakaia 

 — published by authority of the Provincial Government — are the 

 principal ones, and to them I have to refer the reader who wishes to 

 obtain fuller information on the subject. When, in 1S62, I published 

 my first account of the drift formation of Canterbury, I had, with the 

 imperfect data before me, come to the conclusion that the Glacier 

 period in New Zealand had begun during a submergence of the country, 

 and that the country had gradually risen during that period to as high 

 a level as it occupies at present. This conclusion was forced upon me 

 by observing a few miles below the gorge of the Eangitata a series of 

 "beds resembling the boulder clays of Europe. Some minute pieces of 

 shells were found by myself amongst them, appearing, from a careful 

 examination, to be portions of a Unio ; others, somewhat larger, 



