Otago Institute, 7f 



He believed that this glacial period must have been in the Pleistocene age, which 

 made New Zealand's, ice age contemporaneous with that of the Northern Hemisphere. 

 In this period Ruapehu was a centre of dispersion, from which glaciers radiated into the 

 Rangitikei, Wangaehu, Upper Wanganui, and Upper Waikato, the latter flowing into 

 Taupo Basin through Rangipo Desert. 



Professor P. Marshall stated that he did not at all agree with Professor Park's views. 

 The Ruapehu country was coimtry with which he was perfectly familiar. He did not 

 regard its appearance as being due to glacial action : it was, he believed, solely the result 

 of river-action. At a comparatively recent geological period it had been on the sea- 

 floor. It had been raised up 4,000 ft. by degrees, and rivers had thereby flowed all over 

 it, depositing the gravels spoken of. Professor Park spoke of and no doubt regarded 

 them as tills ; but to the speaker they were nothmg more than river-gravels, deposited 

 at different times. After referrmg to certain geographical features of the country, 

 Professor Marshall said that Ruapehu had been examined by many geological students, 

 who had quite failed to discover the deep-scored valleys or any other signs of glaciation. 

 The region had recently been the subject of a detailed geographical survey by Mr. 

 R. Speight, who found no such evidence of glaciation. He personally had gone there iil 

 his young days, hoping to distinguish himself, but he had come away again without 

 havmg found any proof of glaciation. He considered that there were no traces of glacia- 

 tion in any of the mountain-ranges referred to by Professor Park ; but that depended, 

 after all, in what way different geologLsts read certain signs. He would personally 

 regard the boulder-clay, if he looked at it m the same light as Professor Park looked .at 

 it, as undoubted proof of glaciation at Tongariro, for it was to be found there. How did 

 Professor Park account for the absence of erratics, which should have been present in 

 the case of such a glacier as had been described ? Of course, they might occur, but had 

 not been described. And surely there would have been a terminal moraine as plainly 

 distmguishable as that at the Taieri, m the case of a glacier forty-five miles long. 

 Professor Marshall concluded by saymg that many geologists had given their decisions 

 against the theory of a glacial period in any j^art of the North Island. 



Mr. G. M. Thomson, M.P., said that all botanical evidence was dead against the 

 glaciation theory, so far as he knew. 



Professor Park, in replying, said that Professor Marshall was under an entire mis- 

 apprehension. There was no river-gravel or water-worn material in the deposit, which 

 consisted of piles of angular volcanic blocks that were largest and most numerous at the 

 southern limit — that is, farthest from their source at Ruapehu — which, of course, would 

 not be the case with river-material. He was the only geologist who had made a detailed 

 exammation of that coimtry, having spent the summer of 1886-87 making a geological 

 survey of the Main Trunk route as far as Ruapehu, on behalf of the New Zealand Govern- 

 ment. The evidence that he had now brought forward was quite new to geologists, the 

 country over which the deposit was spread being covered with dense forest until quite 

 recently. There was, Professor Park said, no other agency than ice capable of trans- 

 porting such masses of rock so far from their source and spreading them over hill and 

 dale. 



The further consideration of the subject was adjourned to a special meeting of the 

 Institute to be held on the evening of the 24th instant. 



Fifth Meeting : lUh Se/ptember, 1909. 

 Professor J. H. Scott, M.D., in tke chair. 



Papers. — 1. " Notes on some Rocks from Parapara, Bluft Hill, and Wai- 

 kawa," by J. Allan Thomson ; communicated by George M. Thomson, F.L.S. 



The author describes in detail six specimens from Parapara, furnished by Dr. Bell, 

 Director of the Geological Survey, the object being to test the rival theories of assimila- 

 tion or absorption, as^propounded by Levy and Lacroix, and of differentiation, sup- 

 ported by Rosenbusch. The investigation serves chiefly to draw attention to the ques- 

 tion, as the phenomena observed admit of either interpretation. A thorough chemical 

 examination of the rocks would be required to settle the problem. 



The rocks from the Bluff were collected along the shore on the south and west of 

 Bluff Harbour. The relative ages of-, these different rocks— fine-grained banded horn- 

 blende schists, and dark and light diorites — the mode of origin of the foliation, whether 



