362 LIEUT.-GEN. C. A. MCMAHON ON [M»y 1900, 



extension of the three marble-beds of Nilt-Hini described on p. 351 

 of this paper. Some limestone-specimens were also collected by 

 Sir Martin Conway in the Bagrot Valley, which doubtless represent 

 the eastern extension of the bed between Gilgit and Nomal. 



Col. Godwin-Austen, F.R.S., informs me that wheu in Kashmir 

 he traced the Carbo-Triassic Series up to the top of the Nushik 

 Pass ; and Capt. Roberts tells me that the valley running up from 

 Hunza to the Shimshal Pass, looked at from the Hunza side, appears 

 to be all limestone. 



The limestones of the Gilgit-Kilik section extend in a westerly 

 direction into the Yasin and Ashkurman Valleys, and my son informs 

 me that they crop up still farther west at Chitral and also in the 

 Bimborit Valley (Bumboret of Curzon's map) which runs into the 

 Chitral Valley from the west above Kala Drosh. In the Bimborit 

 Valley bluish-white limestone and slate, both resembling those 

 of the Gilgit-Kilik section, 2 or 3 miles wide, occur, dipping 

 vertically and associated, as usual, with granite. 



I also note that Mr. C. L. Griesbach, C.S.I., now Director of the 

 Geological Survey of India, in his geological map of Afghanistan, 

 records an extensive outcrop of the Carboniferous and Permian 

 rocks between Jellalabad and Kabul, and again to the north and 

 north-west of Kabul. Both these outcrops, like those of Gilgit, are 

 much invaded by masses of granite. 1 



As this great conformable series has been identified in the 

 Kashmir Valley by competent geologists up to the borders of Gilgit ; 

 as it can be traced from the borders into Gilgit; and as it reappears 

 on substantially the same strike on the other side of Gilgit in 

 Afghanistan, I think I may venture to claim the Gilgit Series 

 as identical with the Carbo-Triassic Series of the 

 North-western Himalaya. 



Several of the Gilgit rocks are remarkably like some of the 

 Himalayan rocks. For instance, the bluish-grey micaceous slate 

 between Hatun and Chatorkand (p. 359) could be matched by 

 specimens at Dalhousie on the cart-road below Balun. The white 

 quartzite at Barjagal, with a micaceous glaze on it (p. 360), 

 is not distinguishable lithologically from the milk-white Krol 

 quartzite in the Satlej Valley at Nogli. 



There are other points of resemblance. In the North-western 

 Himalaya, and in Kashmir, a volcanic series comes in at the top of 

 the Silurian and the lower part of the Carboniferous Series ; and 

 there is some evidence to show that similar rocks occur in the Gilgit 

 area at approximately the same horizon. What appear to be altered 

 volcanic rocks are found below the Nilt-Hini marbles (p. 350), and 

 ash crops up in the Yasin section (p. 357) and in the Ashkurman 

 Valley (p. 359). 



Capt. Roberts's description of the ' stinkstones ' at once brought 

 forcibly to my mind the Krol Series of the Simla area. In the 

 matter of colour, however, there is a great difference. The Krol 



1 Kec. Geol. Surv. Ind. vol. xx (1887) p. 93. 



