1869.] features of the Jaintia hills. 153 



either due to a falling in of the limestone, or, as I am more inclined to 

 think, to a prior denudation of the limestone surface. The fossils are 

 minute with an occasional Grastropod of larger size. This ridge on 

 the north of which lies Nongldi, well known as one of the last strong- 

 holds of the Jaintias during the rebellion of 1861-62, is succeeded 

 on the south by the main ridge and the watershed of the hills, the 

 stream at Nongldi being a feeder of the Kopili. Crossing a low pass 

 at the head of the last mentioned stream, the view that suddenly 

 opens out, is almost Himalayan ; below lies the deep valley of the 

 Umsnat, backed on the east by the high mass of Marangksi, its 

 precipitous cliffs shewing out grandly against the noble forest that 

 covers all else. In this great section, everything above the Nummu- 

 litics is exposed, this last forming the bottom beds in the valley 

 succeeded by the fossiliferous ferruginous strata, and again above by 

 an enormous thickness of soft, thick-bedded sandstone of light ochre 

 tint ; — this higher mass is the universal rock of all the higher forest- 

 clad hills running thence due east to Asalu. In the bed of the 

 Umsnat, the limestone is almost horizontal, but lower down has a very 

 slight dip southward. It also thickens in this direction very rapidly 

 with interstratified beds of sandstone. 



The whole mass preserves its horizontality, and there is nothing very 

 noticeable over a large and broad band, save that with the deepening 

 valley lower beds of the limestone are exposed, but in no spot did I see 

 sandstone of secondary age, or one that could be mistaken for it. The 

 Umsnat joins the Simleng, and the united streams become the Lubah, 

 which forms a junction with the Barak near Molagul. The Simleng 

 and Lubah form a deep valley with an east and west strike, and the 

 mass of the upper nummulitic or tertiary sandstone rises precipitously 

 on the south, forming a ridge parallel with it. Upon this line, the first 

 bending over to the south commences. The best section for observing 

 this peculiar formation is near Katom, where the Lubah turns south in a 

 gorge, cutting diagonally right across the whole mountain mass. The 

 solid limestone of great thickness, perhaps 1,000 feet, and the higher 

 sandstones all have the same great incline, becoming afterwards perpen- 

 dicular and being succeeded at this above mentioned point by a thin- 

 bedded series of newer rocks, clays and sandstones, of various colours 

 and hardness. The angles of clip vary slightly north and south 



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