DoBSON. — On the Date of the Glacial Period. 441 



of the last great Glacial Period of New Zealand, by Captain Hutton, without 

 which the consideration of this subject would be incomplete. The author's 

 views, briefly summarised, are as follows : — That the greatest extension of the 

 glaciers was coincident with the greatest elevation of the land, and occurred in 

 older pliocene times, which was a period of elevation ; the newer pliocene 

 period was one of subsidence j followed by elevation in pleistocene times, and 

 that elevation is still going on. 



In volume VI., Mr. W. T. L. Travers, in a paper on the Extinct Glaciers 

 of the Middle (South) Island of New Zealand, infers that the extension of 

 glaciers was due to a great elevation of the land in miocene times, which 

 elevation continued into and was greatest during pliocene times, when 

 subsidence commenced and continued into pleistocene times, during which a 

 fresh upheaval took place ; and that in consequence of the elevation of the 

 land, and a much larger area being above water, New Zealand assumed a 

 quasi-continental character. 



Mr. J. T. Thomson, F.R.G.S., (Glacial Action in Otago) considers the 

 island must have been at a considerably lower level than at present, the land 

 covered with glaciers, and surrounded by a wintry ocean, the country generally 

 presenting similar features to Victoria Land in the Antarctic Ocean. The 

 author, so far as I can learn, does not touch upon the question of geological age. 



In a paper written by myself (Notes on the Glacial Period), the greatest 

 extension of the glaciers was considered to be due to elevation, which com- 

 menced towards the close of the pliocene period and continued, the greatest 

 elevation of the land being marked by the greatest glacial extension j subsidence 

 then took place, continued up to the present time, and is still continuing. 



So far I have briefly given the views advanced by the writers of the papers 

 before mentioned ; but, in addition to the papers, we have the remarks made 

 by Doctors Hector and Haast in the annual addresses published in the 

 Proceedings, which will well repay perusal, and to which I shall allude 

 subsequently, merely premising that, from what I haA^e read of the writings of 

 these gentlemen, if I understand them aright, they neither consider much 

 elevation of the land to have been a necessary accompaniment to the glacial 

 period, referring the change more to other causes — the wearing away of 

 mountains, etc., and possibly to changes in the relative proportion of land and 

 water in the neighbourhood of New Zealand. 



Messrs. Hutton, Travers, and myself are agreed in supposing a great 

 elevation of land to have been the primary cause of the extension of the 

 glaciers, and subsequent depression the cause of the extension, but difier 

 materially as to the date of the elevation and subsidence respectively ; Captain 

 Hutton considering the old pliocene period one of elevation, the newer pliocene 

 one of subsidence, followed by elevation, which he supposes to be at present 



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