10 MALLET : GEOLOGY OF DARJILING AND WESTERN DUARS. 



mountain streams, and the only practicable way of obtaining anything 

 like continuous sections is by wading and scrambling up these. The 

 boundaries, as laid down on the map, were obtained by doing so, and con- 

 necting the junctions observed in one stream with those visible in the 

 next ; hence the band of Damiida rocks seems to have a greater degree 

 of regularity than it probably possesses in reality. An exhaustive 

 survey would probably bring to light cross-faults and other features which 

 have escaped detection. 



No Damudas are visible between the Mechi and the Balasan. In 

 No Damtidas west of * ne Manjha, the Chenga ; and the Dudhia streams 

 the Tertiaries are seen close up to, or near, the 

 slates. The Damudas seem to have been denuded away before the Ter- 

 tiary epoch. It is, however, not unlikely that the band is found further 

 west in Nepal. 



In some of the small watercourses between the Balasan and the 

 Damudas near Panka- roa( ^ a ^ Kelabari, the Damudas are just seen at the 

 very base of the hills, with clay slates above 

 them. They are chiefly shaly sandstones, with a seam or two of coal 

 two or three inches thick ; in the most westerly of these ravines both 

 rocks dip north 25 west at 80°. No Damudas are visible in the 

 Bissarbatti stream, but the space they ought to occupy (below the bridge 

 between Kelabari and Pankabari) is blank ; and there is but little doubt 

 that they are present there. A three -feet bed of carbonaceous shale, 

 dipping at a low angle to north-west, outcrops in a watercourse just 

 west of Pankabari dak bangalo. It is by no means easy to separate 

 the Damudas from the Dalings near this, as some of the beds in the 

 coal-series are as good clay slate as any in the Dalings. 



A small ravine joins the Bissarbatti stream a little below the bridge 

 above-mentioned. Ascending this, Tertiary sandstones are first met; 

 a short way from the mouth these abut against a two -feet bed of 

 carbonaceous shale, above which is rather indurated quartzo-felspathic 



( 16 ) 



