6 LAKE: GEOLOGY OF SOUTH MALABAR. 



The Pandika"d River is the only one that rises to the east of the 

 central high land and cuts its way straight through. There is reason 

 to think that, in former times, this river, like all the others rising in the 

 Ghats, also flowed in the ring-shaped moat. It probably fell into the 

 Beypore River to the north. 



The three greater rivers already mentioned, vzz., the Beypore, 

 Kadalhundi, and Ponnani, receive the whole of the drainage of the 

 area. The Beypore is formed by the junction of a large number of 

 streams in the Nilambur Valley, some of these streams rising in the 

 Nilgiri plateau. The Kadalhundi receives only one important tributary, 

 viz., the Pandika"d River, the Angddipuram River being really the main 

 branch and not a tributary. The Ponndni receives a great number 

 of streams before entering this area ; but in the area under consider- 

 ation, the only important tributary is the Tudhakal River. 



All these rivers flow throughout the year. They become very 

 shallow in the hot weather, but never dry up. 



The climate of Malabar is very damp. The average annual rainfall 



is about i<}6 inches, of which about half falls in 

 Climate. J ' 



the months of June, July, and August during the 



South-West Monsoon. The driest months are January and Feb- 

 ruary. 



Owing to the nature of the climate and the character of the soil, 

 forests are very large and important. Trees 

 and bushes cover almost the whole of the gneis- 

 sic area ; but cannot gain a footing on the older laterite. Fresh 

 laterite, such as is found in the valleys, is not unfavourable to the 

 growth of underwood and even of large trees ; but the finest forests 

 are found near the Ghats. All the slopes of the hills, except those 

 too steep to support soil, are covered with trees ; while the tops of 

 the ridges (in the Silent Valley and Palghat Hills) are mostly grass- 

 covered. The whole of the Nilambur Valley, an area of some five 

 hundred square miles, is filled with lofty forest, of which a magni- 

 ficent view may be obtained from Nilambur Hill. 



The occurrence of these large forests and especially of very thick 

 underwood adds considerably to the difficulty of the survey of the 

 ( 206 ) 



