12 mallet: geology of darjiling and western duars. 



Pankabari nearly as far as Dalingkot. Here some faulting, combined 

 with a change of strike, cuts them out, and the slates reach to the foot 

 of the hills for several miles, but in the Mo-chu the Damridas are found 

 again in their old position. Some beds occur near Baxa bearing a 

 resemblance to the same formation, but the neighbourhood of Dalingkot 

 is the most easterly point at which indubitable Damiidas have been 

 observed. Whether the coal-bearing series outcrops anywhere in In- 

 dependent Sikkim is a question yet awaiting determination. 



There is a very large development in the Duars of variegated slates, 

 which differ considerably in lithological characters from those of the 

 Darjiling district, and which, besides containing thick bands of quartzite, 

 &c, include a band of dolomite not less than 1,500 or 2,000 feet thick. 

 How far these two groups of slates may be distinct from each other is 

 uncertain, but there are sufficiently strongly marked points of difference 

 to justify one in separating them, at least provisionally. I have accord- 

 ingly applied the name of ' Baxa ' to one series, which is largely developed 

 in the neighbourhood of that cantonment, and ' Daling ' to the other, as 

 it is well seen in the neighbourhood of the old Bhutanese fortress. 



The Tertiaries in the Darjiling district, as along the Himalayas 

 generally, occur as a narrow band fringing the base of the hills. The 

 existence of gaps in this fringe near Daling and west of the Tursa river 

 is a most unusual phenomenon ; in fact, these are the only instances as yet 

 known in which the continuity of the Tertiary band is broken, from the 

 Brahmaputra to the Indus."* 



The alternating quartzites, dolomite, and slates of the Baxa series 



Orography as influenced nave naa * a marked influence in determining the 

 by stratigraphy. erosion of the hill ranges in the Duars, where the 



two first rise into elevated ridges. In the Darjiling district these rocks 



are absent ; there, while the several formations as wholes differ consider- 



* Fide Vol. IV, p. 436. 

 ( 12 ) 



