AUSTRALIAN CAINOZOIC (TERTIARY) DEPOSITS. 73 



would be sufficient to account for these changes of climate on the 

 surface of the globe. 



Prof. Ramsay could not agree with the last speaker in thinking 

 that radiation in cooling would produce any palpable effect on the 

 surface of the globe. So far from there being any proof that the 

 climate. had been gradually growing colder from the earliest times 

 down to the present date, there was every evidence to show that 

 glacial periods had recurred at different periods in past time. Dr. 

 Duncan and Mr. Evans had merely given suggestions, but had not 

 solved the problem and proved that the poles did not occupy the 

 same position in Miocene times that they do today. Darwin and 

 Dana were both agreed in thinking the present continents to be of 

 extreme antiquity. Great elevations of land had taken place prior 

 to the Miocene epoch. The Alps and the Himalayas were both 

 pre-Miocene, and were probably higher in pre-Miocene times than 

 at present, having been subjected to great denudation. 



Mr. Gwyn Jeffreys pointed out that certain species of shallow- 

 water mollusca now found in the Arctic Ocean had formerly in post- 

 Tertiary times lived as far south as Sicily. 



Dr. Wright remarked that there was a wonderful similarity be- 

 tween the Miocene echinoderms from Australia and those found at 

 Malta. 



Prof. Morris considered the abundance of Echinoderms belonging 

 to the Spatangoid group in these Australian beds to be very interest- 

 ing. The feature presents itself in the New-Zealand Tertiaries, 

 where forms allied to Arachnoides occur. The distribution of these 

 Echinoderms in New Zealand was excessively complex and difficult 

 to understand. There was a remarkable similarity between the 

 Miocene floras of Greenland and Central Europe ; and the question 

 to be asked was, Did they spread over a continent formerly existing 

 between these points, or had they emigrated from some one central 

 spot ? 



Dr. DtnsrcAN-, in reply, stated that it was only by the united inves- 

 tigations of all students of geology that the question could be in any 

 way settled. The belief in the recurrence of glacial epochs was 

 founded on some erroneous conclusions drawn from beds in South 

 Africa, which were really nothing more than a volcanic dj^ke, and 

 from some deposits in India at the base of the Himalayas. The 

 Miocene plants could not have existed without sufficient light, and 

 therefore could not have extended so far north under conditions si- 

 milar to the present. The Echinoderms did certainly present a 

 striking resemblance to those found in the Miocene beds of Malta ; 

 but there were still sufficient specific differences to justify him in 

 describing them as distinct. 



