18 Geological Notes on the KTiasi Hills. [No. 1, 



sandstone of light colour. A bed of carbonaceous sbale above this 

 contained a good deal of shining iron pyrites, and was very heavy. 

 A steep ascent here commences, up a spur, bounded on the north by 

 a lateral valley of the Riangwylam, we had just crossed. Beds now 

 were seen, with the rise to have an easterly incline, or the commence- 

 ment of another great roll in the sandstones. Near the top a trace 

 of coal was found, but nowhere in the forest could I find a satisfactory 

 section. The thick debris covered the ground too deeply, the associated 

 beds being very fine sparkling, lilac coloured sandstones. At the top 

 of the final ascent, where an open glade in the forest was entered, 

 the surface sandstones were of a very gritty coarse description, with thin 

 beds of water-worn quartz pebbles, and had more the look of the 

 coarse beds seen near Maobelurkur, &c. After crossing a ravine 

 where the dip is south, these beds are seen capped by the lowest 

 strata of the nummulitic rocks, but it is a mere outlier and only some 

 20 feet thick. Several other isolated masses are contiguous. The sand- 

 stone, beyond this a short distance towards the village of Nongum- 

 lai, dip with the surface level of the ground, and is evidently of the 

 same hard durable kind, that occurs near Nongkerasi, but here it is 

 thrown up several hundred feet higher, falling towards the south-west 

 to rise again in a higher roll, in the culminating scarp of Pundengroo. 

 The village of Nongumlai is a very good central point, whence 

 the geology of this neighbourhood can be studied. It stands on an 

 open bare slope of the hard sandstone that terminate a few hundred 

 yards below, in the main stream, a source of the Um Durliang flow- 

 ing to the south. Immediately beyond this stream a densely forest- 

 clad hill rises rather abruptly, all of nummulitic limestone, tbe surface 

 of the slope being as usual, most fantastically eaten away. Thence to 

 the south a very large area covered with forest is also of this rock, in 

 which all trace of drainage lines ceases, water finding its way down 

 the innumerable crevices and holes, or rather wells in tbe rocks, for the 

 word hole hardly expresses the deeply honey-combed state, it presents. 

 Land shells literally strewed the ground, principally large Cyclophoridce. 

 Tbe limestone here presents a thickness of some 250 to 300 feet, and 

 is very similar in stucture, colour and hardness throughout, none of 

 the blue and clayey bands being seen. Both in the stream and near 

 the top of the ridges, transported small lumps of the fossiliferous 



