92 Journal of the Asiatic Society of Bengal. [N.S., XV. 
retaining the same character, diminish in thickness towards the 
S.-E., being reduced to 1,000 feet or so on the Jumma and 
barely represented on the Ganges. The topmost beds, known 
as the Kasauli stage, are found in various places between the 
Jhelam and the Jumna and are probably a lake deposit. 
The Murree beds exist in the Kala Chitta hills, where they 
are perhaps 2,000 feet thick, but they thin out going south to- 
wards the Salt Range, where they appear to be represented by 
finer-grained and more concretionary beds which are only of a 
triflmg thickness. South of the Salt Range they die away 
entirely. 
The Lower Siwaliks consist of a great thickness of sand- 
stones. known as the Nahan series, probably reaching their 
maximum development of some 10,000 feet between the Sutlej 
and the Jumna, though there is little doubt that they formerly 
existed in probably equal amount to beyond the Ravi, but are 
concealed from view by faulting. Eastward they gradually die 
out, being less than 5,000 feet thick beyond the Ganges, while it 
is doubtful whether they extend beyond the eastern border of 
Nepal. East of the Teesta the Siwalik series with a total thick- 
ness of 11,000 feet! partakes rather of the nature of the coarse- 
grained pebbly sandstone of the Upper Siwaliks. 
The Lower Siwaliks are absent over the larger portion of 
the Murree hills but descending towards Rawal Pindi they 
overlie the margin of the Murree series. 
e go south to the Salt Range, they alter in character 
and consist largely of fine-grained, nodular and concretionary 
clays with interbedded sandstones belonging to the Kamlial 
and Chinji zones. They are some 4,000 feet thick here, and, 
beginning in the Tortonian, extend through the Sarmatian stage 
of the Upper Miocene. Their lithological character is partially 
continued in the Nagri beds of the lower Pontian. South of 
the Salt Range, beds of Lower Siwalik age occur in the Bugti 
hills and Sind, being in both localities of a concretionary charac- 
ter but coarser than in the Salt Range. 
At the top of the Nahans some few hundred feet of beds 
were deposited of a lithological composition precisely similar 
to the Lower Siwaliks of the Salt Range. These are probably 
lower Pontian and belong to the Nagri horizon. They are devel- 
throughout Kangra and the Simla hill states, being every- 
where fossiliferous and especially so at Haritalyangar in the 
Bilaspur State. 
The Middle Siwaliks which succeed them are coarse cream- 
coloured sandstones with occasional pebbles and a few inter- 
1 Mallet, l.c., p. 47. 
