80 FAUNA ANTIQUA SIYALENSIS. 



II. OIS" THE STRUCTUEE OF THE SEWALIK 

 HILLS, AND THE ORGANIC REMAINS 

 FOUND IN THEM.' 



BY PKOBY T. CAUTLEY, ESQ., CAPT. BENGAL AETILLERY, F.G.S. 

 {Read March 9, 1836.) 



The momitains, a part of wliich I am about to describe, range 

 (with tlie exception of the debouchures of rivers) almost un- 

 interruptedly from the Sutlej, which separates the territory 

 of the British Government from that of the Sikh chieftain, 

 Runjeet Sing, to the Brahmapootra river, and the district of 

 Cooch Behar. Their general bearing, in the portion near 

 the Sutlej, is ISW. and SE. ; but in that approaching the 

 Brahmapootra it is many points nearer direct east and west. 

 They lie at the foot of the great Himalayan chain, with which 

 they are in some parts connected by a succession of low moun- 

 tains ; but in others, as in the districts under review, they 

 are separated by valleys from three to ten miles in width, and 

 called by the natives Deyra Dhoon, Kearda Dhoon, &c., or 

 the YaUey of Deyra, the Yalley of Kearda, &c. The highest 

 peaks do not far exceed 3,000 feet, and the generality of the 

 summits vary from 2,000 to 2,500 above the level of the sea. 

 It is necessary, however, to premise, that my observations 

 have not extended further eastward than the Ganges ; and 

 that whatever I may record in this paper beyond that river, 

 is given on the authority of others. 



Between the Ganges and Jumna rivers, this line of moun- 

 tains is separated from the great chain of the Himalayahs by 

 the Dhoon, or valley of Deyra, the average width of which 

 may be under ten miles. At the Ganges, or south-eastern 

 extremity, a road passes between the chain and the river ; 

 and no difficulty whatever is offered to the approach to the 

 valley. At the opposite or Jumna extremity, on the contrary, 

 the mountains a,re in many places scarped into the river ; 

 and the footpath used by the boat and raft people is an irre- 

 gular track, over ridge and through hollow, and impinges 



' This memoir is reprinted from the Geological Transactions, yoI. v., Second 

 Series, p. 267.— [Ed.] 



