THE BIRDS OF NORTHERN THAILAND 



21 



roseus, Dissoura e. episcojnis, Xenorhynchus a. asmticus, Leptoptilos 

 dubiits, Pseudibis p. davisoni, and Ploceus m. peguensis. All are com- 

 mon and widely distributed on the Chiang Rai marshes but are quite 

 unknown from other northern provinces, entry to which has been 

 denied from the north by Chiang Rai's barrier wall of mountains, 

 from the south by the narrow gorges through which all rivers of the 

 Chao Phaya system flow between the northern plateau and Thailand's 

 central plain. 



Map 3. — Fanual areas of northern Thailand: 



1. Northern division. 



2. Western division 



3. Eastern division 



