68 GEOLOGICAL NOTES ON KOSCIUSKO, 



glaciation in Australia and South Africa (Ramsay's Permian 

 breccia is now otherwise explained). Similarly, though there are 

 remains of Pleistocene glaciation in the lands between 40-50° S., 

 there does not appear to have been any such extreme glaciation as 

 affected corresponding latitudes in Europe and America. 



" (2) Even adjacent glacial areas are not subject to their maxi- 

 mum glaciation at the same time. Thus N. America has had four 

 main glacial centres, the Cordilleran (Rocky Mountains), the 

 Kewatin (Minnesota, ikc), Labrador, and Greenland. The glacia- 

 tions at these centres succeeded one another from west to east. 

 The Labradorian glaciation was the last on the mainland; it was 

 succeeded by the growth of the Greenland glaciers, which have 

 perhaps not yet reached their maximum. The evidence certainly 

 points to the fact that the Greenland glaciers have now a greater 

 extension than they have ever had before. 



" (3) Schloessing's theory seems probable. According to this 

 the sea is a great reservoir of COo held in the form of bicarbonates; 

 any diminution in the COo content in the atmosphere at once 

 leads to dissociation of the bicarbonates in the sea, which thus 

 automatically regulates the amount of CO 2 in the air. Any such 

 variation as Arrhenius' theory requires would, therefore, be 

 impossible. 



"In face of the evidence of the variation of COg in latitude 

 (summarised by Letts & Blake), and of Dittmar's opinion that 

 Schloessing is right, we cannot safely assume an adequate CO 2 

 variation in the atmosphere. Dittmar's opinion was founded on 

 his own experiment,. showing that the dissociation of bicarbonates 

 in sea water corresponds to the COo tension in the air." 



With reference to argument (1) mentioned above by Professor 

 Gregory, we think should be considered the very important dis- 

 covery by Mr. Walter Howchin, F.G.S., of immense glacial 

 boulder beds in the Lower Cambrian of S. Australia, extending 

 over at least 400 miles of latitude, as recorded in his paper just 

 read to the Royal Society of South Australia. This glaciation 

 may perhaps be homotaxial (though not necessarily synchronous) 

 with that of the Cambrian (?) glacial beds of Scandinavia. 



