OLDHAM : GEOLOGY OF MANIPUR AND NAGA HILLS. 7 



bearing in mind that the rocks of the Chatik ridge almost certainly 



belong to the older series, the line of demarcation between the two must 



in this neighbourhood be drawn not far below the limestone. 



14. We now come to the very important question of the age of these 



two series respectively, and here we are balked at 

 Ages of the two series. . 



the outset by the entire absence or any trace or 



fossils, but notwithstanding this we can, I think, make a very good guess 



at the truth. The most important clue we have is the limestone of the 



Nung-shong-kong valley; this limestone is of a very peculiar character, 



and is absolutely identical in appearance and 

 Cretaceous? . . 



structure with a greyish limestone, which in Pegu 



has been classed by Mr. Theobald as of cretaceous age. If this identifica- 

 tion be correct, the older of the two series would 

 Axials? 



fall into its place with the 'axials' of the Arracan 



Yoma with which they agree in general characters, and be of triassic 



age. The only other clue we have to the age of these rocks is the 



presence of brine springs among them, which would 

 Not nuinmulitic. 



point to a nummulitic age for the series ; but 



seeing that, as I shall presently show, both are as may be inferred from 



the great unconformity at the junction vastly older than other rocks of 



miocene age, and as the brine springs occur in the older and not the 



newer of the two series, viz., among the 'axials/ which under any 



circumstances could not be of nummulitic age, no great weight can be 



attached to this fact. But though these rocks cannot possibly be of 



Possible presence of nummulitic age, it is not improbable that other 

 numrnuhtics. rocks of that age do exist in this district, for, as 



was pointed out in paragraph 1 1, there is possibly a third series which, 

 lying between the cretaceous and miocene, would fall into its place among 

 the rocks of eocene age, 



1 5. I must now pass on briefly to describe the older rocks north of 



Axials of North Maui- Manipur and in the Naga hills. The road from 

 pur and the Naga hills. Manipur to Kohima lying almost along the strike 

 of the rocks, little but grey and black slates with a north and south 



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