STRATIGRAPHICAL FEATURES. 67 



micaceous. Throughout the horizon fossils are found, — chiefly Pro- 

 ducti of latest carboniferous or permian type. The best preserved 

 specimens are contained in the grey sandstone partings which are 

 often crowded with Producti. 



Stoliczka noticed these beds, which, amongst other localities, are 

 also well developed at Ruling in the Spiti valley, and he named the 

 horizon in consequence the Kuling shales. But he did not notice that 

 only about one-half of the thickness of these dark shales have yielded 

 Brachiopods of later palaeozoic type, and that some very dark shales 

 above, which are also well seen at Kuling, really belong to the lower 

 trias, which he considered altogether absent in the Spiti area, I feel 

 therefore that the retention of the term Kuling beds for this horizon 

 would be misleading, as the entire thickness of the Kuling shales 

 of Stoliczka certainly does not belong to the carboniferous system. 



I have seen specimens of the "Kuling shales" of Kashmir, which 

 show that identically the same rock extends far to the north-vvest- 

 wards~of the Central Himalayas. 



In normal sections the total thickness of this division varies from 



120 to 250 feet, but being a soft and easily dis- 



Thickness. 



turbed deposit, it has suffered very largely from 

 crushing and folding. The more rigid strata of the triassic system 

 have often been pushed over the carboniferous beds, during which 

 process the soft Productus shales have naturally suffered most. 

 On such occasions, in fact, the dark shales have acted the part of a 

 lubricator between the rigid strata of the carboniferous and trias, 

 themselves being crushed and distorted, whilst the trias block was 

 pushed over the carboniferous formations. The same phenomenon 

 may be observed frequently in all disturbed areas where soft shales 

 divide systems of more rigid nature, such as hard limestones, etc. 



6' Triassic System. 

 Although sharply and abruptly defined at its base in all the sections 

 Passage into beds which I have examined, the dark Productus 

 above - shales may be said to pass gradually up into the 



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