644 president's address. 



Professor Tate in his address to Section D. of the Aust. Assoc, for 

 the Advancement of Science in Sydney, 1887, divides the flora of 

 AustraUa, as follows : — 



I. Immigrant. 



a. Oriental. 



b. Andean. 



II. Endemic. 



1. Euronotian or eastern. 



2. Autochthonous or western. 



3. Eremian or central. 



He says that between the Euronotian and Autochthonian a 

 barrier always existed ; in Cretaceous times it was to a large extent 

 lacustrine, later on the lakes dried up and the present desert barrier 

 formed. 



His conclusions are : (1) that the Australian flora is of high 

 antiquity ; (2) that the Autoclithonian constituent was dis- 

 membered in Cretaceous times and, (3) that the Euronotian con- 

 stituent was moditied during very early Tertiary times by a 

 j)rimitive cosmopolitan flora. 



I do not see much to dispute in the above except the supposed 

 existence of a cosmopolitan flora, which is a mere assumjDtion. 



Now let us see what is to be learnt from the study of fossil 

 plants as to the former land surfaces of the southern hemisphere. 



In the Australian Coal Measures, which are now acknowledged 

 to be of Permo-Carboniferous age, there is a remarkable absence 

 of the plants which abound in contemporaneous beds of the 

 northern hemisphere, but instead of this we meet with an 

 enormous development of Glossopteris, Gangamopteris, and other 

 genera of ferns which do not occur in the northern hemisphere 

 till a much later epoch. These forms are found over a very large 

 area of the earth's surface, not only in Australia, but also in 

 India and South Africa, and it has been recently announced that 

 a remarkable afiinity with the Australian and Indian Carboni- 

 ferous fern flora has been traced in Argentina in South America. 



