part3] OF THE INDUS, BRA II MAIM TKA, AM) GANGES. 1 \'-> 



reducing the syntactical angles which separate these arcs, we can 

 trace this gulf from Baluchistan and Sind to Eastern Afghanistan, 

 curving eastwards thence through the Pun jab along the foot of the 

 Himalaya as far as Naini Tal. The interruption of the outcrop 

 between the .lanimu hills and Simla, and between the latter place 

 and Dehra Dun, must be attributed to overlap, unconformity, or 

 faulting; but that the beds were continuous is obvious from the 

 occurrence of numinulites in the Naini Tal Nuramulitics, showing 

 a connexion with the open sea. The Nummulitic outcrops of 

 Bikaner and Jaisalmer may belong to the main gulf, or may 

 indicate a small branch of it. 



The Himalayan, Afghan, and Baluchistan movements, there- 

 fore, during the Nummulitic epoch drove the old Cretaceou> sea 

 westwards, Tibet and the whole of the Himalaya (with the ex- 

 ception of the Ladak valley) becoming dry land. They, however, 

 assisted in producing a depression along the base of the continuous 

 series of mountain-arcs, forming a gulf in which a constant 

 struggle took place between the deposition of silt tending to lill 

 up the gulf, and the general subsidence tending to deepen it. 

 Sometimes the silting action prevailed to such an extent as to cut 

 oft land-locked salt lagoons ; this process was assisted by a cor- 

 rugating action, by which the floor of the gulf was folded into 

 small anticlines and synclines, an effect quite apart from the general 

 depression of . the whole as a geosyncline, or geosynclinorium as it 

 would be more aptly termed in places. Much of the Ivumaon and 

 Simla Nummulitic, as well as most of the Upper Nummulitic of 

 the Pot war and Hazara, was presumably deposited in such salt- 

 lakes and lagoons. It is, in fact, possible that at times the gulf, as 

 a whole, was cut off from the sea. East of Naini Tal the hydro- 

 graphic line was probably continued by a river draining westwards 

 into the lagoons, the lagoons coalescing into a marine gulf once 

 more for a short time at the end of the Nummulitic epoch. It is 

 not proposed here to trace the oscillations which took place locally 

 between marine and lacustrine or fluviatile conditions ; but there 

 came a time when, from Simla to the Shiran i Hills, and also farther 

 south, these oscillations ceased, and one type of deposit only was 

 laid down to form the great Murree Series. 



In the Simla area the Murree s are represented by the Dagshais 

 below and the Kasaulis above. The latter resemble the overlying 

 fluviatile Siwaliks, while it has been suggested that the former were 

 deposited in salt-lakes and lagoons. Farther west there is no 

 definite line between Upper and Lower Murrees, the one passing up 

 into the other. The Lower are like the Dagshais, and xcyx similar 

 to the red clays of the Upper Nummulitics of the same area and of 

 the Simla Subathus, for which I have proposed a similar origin ; 

 the only alternative is to regard them as fluviatile deposits. The 

 Upper Murrees resemble a mixture of Dagshais and Kasaulis. 

 These Murree beds have been traced through Kohal and Wazi- 

 ristan, but were not identified in the Shirani Hills farther south. 

 South-we.^t of Dera Ismail Khan, Lower Murrees (Upper Nans 



