NUMMULITIC SERIES. 13 



Immediately under tlie village of Lairmigao, four miles to tlie 

 north of Cherra Piinji, there is a workable seam of coal. There is 

 about the same thickness of rock between it and the cretaceous sand- 

 stone as in the section at Cherra; and at many intermediate points 

 along the road, on about the same horizon, thin coal and coaly 

 shale are well exposed ; so that iu all respects the horizon is well 

 defined. But below the coal at Lairungao the strata are sand- 

 stones, with subordinate shales (often carbonaceous), except at the very 

 base where we find one strong bed of tolerably pure nummulitic lime- 

 stone resting on the cretaceous sandstone. Thus at Lairungao we have 

 the same lowest sub^division of the nummulitic series as at Cherra, and 

 ia about equal thickness, but so greatly altered in composition. 



North of Lairungao there only remains this bottom band of the 

 formation, that represented by the limestone at Cherraj but a still 

 further change takes place — the limestone disappears altogether. At 

 several places north of Surarim unbroken sections are obtainable, and 

 there is no vestige of a calcareous rock. It is with some difiiculty that 

 the exact boundary can be fixed, in the absence of the limestone; 

 although, on the whole, the nummulitic beds can be recognized by the 

 frequent occurrence in them of carbonaceous partings, which are wanting 

 in the upper band of the cretaceous series. About two miles north of 

 Surarim the nummulitic beds stop out altogether near to a rapid rise of 

 the cretaceous beds against the quartzites of the metamorphic series. 

 There is no saying how far beyond this point the nummulitic formation 

 may at one time have extended. Higher beds of the series may formerly 

 have overlapped the rising ground to the north. 



At a few points to the west of Lairungao the nummulitic lime- 

 stone is exposed in its characteristic position. In no case is there more 

 than a few square feet visible, so it will be well to indicate the spots : 

 in the bed of a streamlet a quarter of a mile to east of Mokma ; on the 

 south side of valley, three quarters of a mile to south-south-west of 



w ( 163 ) 



