252 E. D. Merrill 



by cold weather, and no extensive areas in which arid or semi- 

 arid conditions prevailed. In other words, since the beginning of 

 the development of our modern vegetation, Malaysia as a whole 

 apparently has been a continuously tropical region with a re- 

 markably equable climate, ample rainfall, and relatively high 

 humidity. From the limited paleobotanic record, we know this 

 has been true of certain parts of the region in which the Pliocene- 

 Pleistocene plant-remains perfectly match the plants of today, 

 but we can only surmise that this is true for the entire region. 

 Setchell* has suggested that persistently dry areas, or the alter- 

 nating wet and dry seasons characteristic of certain parts of the 

 Archipelago, may be just as important to plant distribution as 

 the geologic history of the region, a suggestion that cannot be 

 ignored; yet it is significant that we find throughout Malaysia, 

 more or less in alternation, constantly wet and alternatingly wet 

 and dry regions; for example, western Java is contrasted to 

 eastern Java, and all the east coast of the Philippines to the west 

 coast. Even in regions dominated by alternating wet and dry 

 seasons there are found certain areas, particularly in the vicinity 

 of high mountains, where precipitation is more or less equably 

 distributed through all months of the year; such areas occur on 

 almost every island in Malaysia which has mountains 4000 to 

 5000 feet high or higher. 



It has been known for many years that the fauna of the Sunda 

 Islands is essentially Asiatic, and that as one proceeds eastward 

 the Asiatic mammals, fresh-water fishes, and certain groups of 

 birds, reptiles, and insects become less and less evident. On the 

 contrary, there are various striking Australian types of insects, 

 birds, and other animals in New Guinea and neighboring 



♦Setchell, W. A., 1929. The Wallace and Weber Lines: a suggestion as to 

 climatic boundaries. Proc. Fourth Pacific Sci. Congr., 3:311-321. 



