14 MEDLICOTTj SHILLONG PLATEAU. 



Mokma ; and at about half a mile to south-west of Rangimasao village. 

 The rock is exactly alike in all — a pale blue, strong, compact limestone, 

 very locally and capriciously shaly, sandy, or granular. It is more 

 fossiliferous than any bed I could find in the limestone 'at Cherra, but 

 unfortunately it is very rarely that any but the weathered sections of 

 shells are obtainable. It may be worthy of notice that this line of extinc- 

 tion of the nummulitic limestone is about coincident with the beginning 

 of the southerly slope of the bedding. The final stopping out of this 

 formation wiU be best described in. connection with the cretaceous 



formation. ' ' 



At the base of the table-land on the left bank of the river, half a 



mile above Theria Gh^t, there is a minimum section of about 1,000 feet 



of nimmiulitic rocks as follows : — 

 Younger Tertiaries.' 

 Blank section. 



Massive coarse blue limestone, interbedded near the junction with ... 200 



Clear yellowish, coarsish sandstone ... ... ... ... 100' 



Fine, compact or chalky, blue or pink limestone ... ... ... 200 



Greenish and ochreous, earthy sandstone ... ... ... 50 



Limestone ... ... ... ... ... ••• 50 



Yellowish sandstone ... ... ... ... ... 100 



Limestone ... ... ... ... ••• ... 200 



Total 



900 



There is a steady high southerly dip throughout. The two lower bands 

 would represent those at Cherra. It is not unlikely that a little exca- 

 vation would disclose a representative of the coal in the lowest sandstone. 

 In the parallel section on the Bogapani, below Chela, there is a coaly 

 layer in the sandstone just over the bottom limestone. There also 

 we find a limestone above this sandstone; but the section is not so 

 complete as in the Theria river. Thus there is every probabHity that 

 the sandstone with the coal at Cherra is truly nmnmuHtic. There would 

 be no proving, from this section, that those upper bands of limestone of 

 the southern locality did not once exist on the plateau j but, on the whole, 

 ( 164 ) 



