2<So 



ANTARCTICA. 



history of the past, as revealed to us by the geologist, shows us 

 that vast climatic changes have taken place. 



Although the exact limits of this huge mass are not yet known, 

 we can assert that it is a continental area larger than Australia. 

 with an average elevation of about 6,000 feet. It is composed 

 of igneous and sedimentary rocks, which rise into high moun- 

 tains and huge plateaux, the South Pole being situated at a 

 height of about 10,000 feet. Other than marine life and avian 

 forms such as Penguins, the only existing representatives of 

 animal and vegetable life are lowly forms such as Rotifers, 

 Protozoa, Mosses, Algae, and Fungi. The absence of higher 

 forms is readily explained by the extreme nature of the climate. 



That this is so is proved by the existence in the past of 

 Ferns and Conifers, etc. In Jurassic times there existed in 

 Graham's Land, now covered with ice and snow, Ferns, Cycads 

 and Conifers, and it is interesting to note in the table below that 

 the same forms once existed in India and the Southern 

 Continents. 



Antarc- South Argen- Aus- 



tica. Africa. India, tine. tralia. 



Sagenopteris .... X — X . — X 



Thinnfeldia X X X X X 



Cladophlebis .... X X X — X 



Pterophyllum .... X X X X 



Otozamites X — X — X 



The significance of this distribution we will discuss later, but 

 it will be noted here that the evidence of these plants proves that 

 in Jurassic times Antarctica enjoyed a much more equable climate 

 than at present. 



Again, at no considerable distance from the South Pole 

 itself, Lieutenant Shackleton's party discovered seams of coal, 

 and returned with a comparatively well-preserved specimen of a 

 fossil Conifer. This was obtained in the Beacon Sandstone, 

 which constitutes such an important feature in the geology of 

 part of Antarctica. The age of this formation is not definitely 

 known, but it is certainly Palaeozoic. 



This indicates that in Palaeozoic times a more equable 

 climate favoured Antarctica. 



The occurrence of fossil conifers and beeches, etc., in Sey- 

 mour Island is proof that, during the time in which the Tertiary 

 rocks of that part were being deposited, the milder condition? 

 which obtained in Jurassic times were continued. 



Now, it is well known that many parts of the earth have, 

 during various periods of the past, been subjected to much colder 

 conditions than now obtain. For example, Australia has been 

 subjected to glaciations at least three times: namely, during Cam- 

 brian, Permo-Carboniferous. and Pleistocene times. South 

 Africa. India, and South America have likewise been subjected 

 to glacial conditions, the Dwyka conglomerate, which stretches 



