GENERAL CHARACTERS. t47 



carnic stage, but their facies is of a dark, mostly black and shaly 

 limestone and therefore differs widely from that of the equivalent divi- 

 sion of the Tibetan series. 



Upper Carnic stage. — The Tropites horizon of the Himalayan series 

 is developed in Spiti as a grey, brown weathering, somewhat shaly, 

 nodular limestone with few, badly preserved ammonites. 1 At the 

 Bambanag cliff, where this horizon has only recently been discovered 

 by myself, 2 it is a grey, shaly limestone alternating with grey shales, 

 which belong to the topmost " Daonella beds." These limestones of 

 the Bambanag cliff also differ faunistically from the Himalayan and 

 Tibetan Tropites horizon by the apparent absence of the genus Tropttes 

 and the general paucity of cephalopoda. In Byans, the Tropites horizon 

 is represented by grey limestones including a rich and well preserved 

 fauna of cephalopoda, among which Tropites is found. The fauna 

 appears to be very much richer than that of Exotic Block 2 and to 

 ■differ moreover by the absence of the genus Cladiscites, which is s© 

 abundant in the Tibetan facies. 



" Dachsteinkalk" (?) — Great masses of unfossiliferous, grey, dolo- 

 mitic limestones, occurring among the exotic blocks, were correlated 

 with the dachsteinkalk of the Himalayan series. It is necessary to 

 state that there is no complete lithological identity between the two, 

 the Tibetan grey limestones being massive throughout, while the 

 Himalayan dachsteinkalk is well bedded. 



Lias. — It has been shown above, that the lias must be looked for 

 in the Central Himalayas in a series of conformable, grey limestones^ 

 ranging from upper triassic into middle Jurassic. It is possible that 

 limestones, including a species resembling Spiriferina obtusa, Oppe!., 

 which I found in Spiti in a section near Gieumal, represent the lias, 

 but so far no unmistakable liassic fossils have been recorded. The 

 red cephalopod limestones traced in Johar thus differ widely from 

 the equivalent Himalayan beds, both in facies and by the fauna they 



include. ' . 



1 General Report, 1899-1900, p. 218. 

 „ „ 1900-1901, p. 28. 



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