iQ^ Ludwig Diels 



Malay Peninsula at least to Queensland. Not a few of them may 

 have increased their area by the help of man, spreading with him 

 to the east. But this cannot apply to all; we must assume that such 

 genera as Nepenthes and Terminalia, and such orders as Sapin- 

 daceae, Asclepiadaceae, and Rubiaceae, reached the boundaries 

 of their extension by the natural means of propagation, even 

 though this happened perhaps only a short time ago. 



From the character of the Malaysian elements, it is apparent 

 that there were connecting pathways from early times. We know 

 that the situation and the condition of these pathways changed, 

 and that they were impassable at certain times and in certain 

 sections. For this reason, the relations between Malaysia and 

 Australia do not appear in all groups of animals and plants in 

 equal manner and in equal strength. But there is no doubt that 

 the degree and the variety of those relations do not agree with 

 the assumption of the displacement theory that Australia entered 

 into connection with Asia only at a late date. If that hypothesis 

 were correct, no peculiar Australian groups of Malaysian affinity 

 would exist. The Malaysian component would prove to be 

 modern. As a matter of fact, such peculiar groups are by no 

 means missing. The whole Malaysian component is not modern, 

 but one of its parts is. These facts cannot be explained by the 

 notions of the displacement theory. In the modern time of earth's 

 history, during the evolution of Angiosperms, we must assume 

 that Australia had a position similar in relation to the other great 

 continents to that which it holds today. An independent evolu- 

 tion of old groups must have been going on in Australia. Besides, 

 influences of southeastern Asia would have commenced early 

 and would be going on up to the present time, whereas the ex- 

 tensions of the Antarctic influences would have affected Aus- 

 traha only temporarily. 



