( 18 ) 





t 



Camping' place onNst-toung". 

 E and W. slopes. 



The above two sketches serve to show this influence of exposure on the Nattoung hills, 

 Martaban. The forests here are stunted hill-forests, while the west and south-west exposures 

 are occupied by hill pastures almost destitute of woodj-^ vegetation. 



The Himalaya belongs geographically to the subtropical zone, and, therefore, might be 

 supposed to form an apparent exception to the influence of exposure as detailed above. But 

 this is not the case at all, for this range belongs, (owing to its great elevation) more to the 

 temperate zone, and, therefore, we see the north-east flanks of the range barren and desolate 

 and confirming the importance of exposure on the grandest scale possible. In fact, if we ascend 

 into the alpine region of Sikkim, we again see all those laws in force that prevail in northern 

 countries, while in the lower portions of the Sikkim-Himalaya, the unfavourable exposures are 

 the same as in Burma 



I have taken exposure into account everywhere in the following description of the Pegu 

 forests, and it is therefore not necessary to specialize here all the variations in vegetation, 

 that are produced by this very important factor. 



Any one who follows up the courses of the numerous choungs along the eastern slopes 

 of the Pegu Tomah, such for example as the Koon and Khayengmathay, will observe also 

 the abrupt change from an evergreen to a deciduous forest, whenever he passes one of the 

 numerous bentings bordered by steep liill sides. If he consults his compass, he will also 

 recognise the importance of exposure as suggested above. Wherever he thinks to have 

 detected an exception to these rules, let him then consult the terrain that surrounds him, and 

 he will find that there is a simple explanation ibr such an apparent exception, and 



