-•V 



HuTTON. — On the Last Great Glacier Period in N. Z. 393 



But independently of all these reasons we find, I tliink, in the marks of 

 former glaciation themselves strong evidence of a very ancient date. In 

 Otago, about Lake Wakatipu, which is the only glacier region in New Zealand 

 that I have had an opportunity of examining, the evidence of the former 

 extension of the glaciers rests almost entirely on the presence of moraines and 

 roches moutonnees, which are the most permanent marks that a retreating 

 glacier leaves behind it. All the more perishable ones, such as blocs perches 

 and striee, are almost entirely absent. I searched in vain on some beautifully 

 rounded surfaces of rock near Queenstown for strise, but all had been 

 obliterated by decomposition, and the only strise that Mr. J. McKerrow and 

 myself could find were on a few loose boulders at the head of the lake. The 

 absence of strise, blocs ijerclies, and other well-known glacier marks, forms a 

 remarkable contrast to what obtains in the Alps, North Wales, and the south- 

 west of Ireland, all of which districts I have personally examined, and this 

 alone would make me refer our glacier period to a time long antecedent to the 

 glacial period of Europe. Strise may be more common in other parts of New 

 Zealand where the rocks are harder than they are in the South, but the 

 absence of any descriptions of them in the reports of Dr. Hector and Dr. Haast, 

 beyond general statements that such exist, makes me think that they must be 

 far from common. 



I am therefore of opinion that the last great extension of our glaciers was in 

 older-pliocene times, w^hen the land stood far higher than it does now ; that 

 the newer-pliocene was a period of subsidence, followed by elevation in the 

 pleistocene period, and that that elevation is probably still going on. 



Note. — November, 1872. The fact that several species of birds and 

 insects are different on the two islands of New Zealand would be considered 

 by nearly all naturalists as a good proof that these islands have been separated 

 longer than Great Britain from Europe, that is to say, previous to the 

 pleistocene period ;* but an elevation of 500 feet would obliterate Cook Strait 

 and join the two islands together, consequently New Zealand cannot have 

 stood at an elevation 500 or 600 feet higher than at present since the pliocene 

 period. We are, therefore, driven to adopt one of two suppositions, viz., 

 either that the former extension of the glaciers was caused by an intense cold 

 or glacial period, or by elevation of the land in prse-pleistocene times. — - 

 F. W. H. 



* Godwin- Austen, " Quar. Jour. Geo. Soc.," VI,, p. 94. 



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