242 NILGfllRI HILLS. 



by the clouds which roll up through it from the Western Coast. Beside 



the principal elevated masses of Dodabetta, the Kundahs and the Hima-' 



galas, there are several small insular outliers, such as that to the North - 



"West of Mailur, the Hoobicul Droog and the adjoining hills, the hills 



to the East of Coonoor, and the two prominent hills already mentioned 



to the West of Ootakamund, all which are bounded partly at least by 



escarpments, more or less distinctly marked. Subsequent fresh-water 



denudation has much modified, where it has not destroyed, most of 



the pre-existing features of the hills, iu some cases rendering the 



escarpments still deeper and more marked, in others cutting through 



them and breaking them up into rounded spurs, so that it is only by 



observing their general outline from some distance, that an idea can 



be formed of their original appearance. 



Iu connexion with the fresh water denudation of the Neelgherries, a 



feature of much interest as bearing on the origin 

 Alluvial deposits. 



of certain of the present vajleys, and affording 



strong presumptive evidence, that at least portions of these valleys existed 

 previous to the final changes of level in the hills, is that of the deposits 

 of alluvium, which, as shown on the map, have been formed by some of 

 the larger streams. The largest and most striking of these is on the upper 

 part of the Pykara river, along the course of which it extends for a dis- 

 tance of more than two miles in a direct line, lapping round the spurs 

 of the adjoining hills, and stretching for short distances into the small 

 lateral valleys which debouch into that of the Pykara. At its lower 

 extremity, the hills advance from each side to the banks of the river, 

 and the stream which up to this point meanders gently through a narrow 

 green plain, here gushes with a considerable fall over a hard band of 

 hornblendic rock which connects the steep hill spurs on the opposing 

 banks. This feature is common to all the alluvial deposits in the hills, 

 and shows clearly that such valleys have been originally closed by a 

 natural bund or dam of hard rock, through which the stream has 



