100 
Records of the Geological Survey of India. 
[vol. IX. 
Lastly, I would conclude with a few words as to the past and present physical features 
of the Siwalik region, and as to the causes which have led to the complete extinction of the 
old Fauna. My remarks will chiefly have reference to that portion of the Siwalik area lying 
between the rivers Satlej and Indus, as being that with which alone I am personally 
familiar. 
The present Siwalik hills consist of a series of comparatively low ranges, with a general 
north-west strike, forming the outermost bands of the Himalaya (see Mr. Medlicott: 
Mem. Geol. Sur., India, Vol. Ill, and Mr. Drew : “ Jamu and Kashmir Territories”), 
here and there pierced through and broken up by masses of the underlying forma¬ 
tions : even their very topmost beds are contorted and crushed in every conceivable manner, 
indicating the lateness of the period down to which the upheaval of the Himalaya has 
extended. 
These hills are either completely bare, or are covered with forests of Finite longifolia 
and Picea Webbiana, or with low scrub jungle: the “duns” between the ridges are gene¬ 
rally cultivated and fairly fertile. The rivers are generally confined to narrow channels in 
deep-cut gorges, and never that I am aware of spread out into lakes: isolated lakes of any 
size are aiso very rare. On the uncultivated lands natural herbage (lit for food) is extremely 
scarce; and in its present condition the country seems to me entirely unfitted for the support 
of a fauna such as that of which we find the remaius embedded in its strata. 
Mr. Medlicott, however, has reminded me that the old Moghul Emperors used to hunt 
the elephant in the Jamu hills; and it therefore seems likely that cultivation must have had 
a share in rendering this part of the country unfit for the habitation of large game. Fur¬ 
ther to the east the Siwalik area still abounds in jungle, in which the elephant is found 
abundantly. 
Several of the Mammalia found in the Siwaliks of Jamu belong, however, to genera 
which live in the open sparingly-watered plains of Africa; such are Hquus and Camelopar¬ 
dalis. The Hippopotamus, however, on the other hand, is only found at the present day inha¬ 
biting large and deep rivers, with pools and lagoons, and on the banks of which grow 
abundance of rank and succulent vegetation; and, to my mind, could not have possibly lived 
in any of the rapidly-flowing rivers of Jamu. 
If, on the other hand, we glance back at what might have been, and very probably was 
the character of the country during the deposition of the Siwalik strata, we may readily 
imagine a physical condition much more suited to animals like the hippopotamus. 
Since, in the Jamft district, at all events, the Siwalik strata are carried up and contorted 
by the conformable underlying rocks, it is evident that these older rocks have only been raised 
at a comparatively recent period to the elevation at which we now find them, and that conse¬ 
quent^ in Siwalik times the whole of the outer belt of the Himalaya must have been much 
lower than at present. This lower elevation would imply a smaller degree of fall in the 
rivers (which Mr. Medlicott supposes to have flowed in the same courses in Siwalik times as 
at present) and these consequently, instead of denuding, would have been depositing in the 
Siwalik districts, and might have wandered in sinuous courses over extensive marshy 
plains, spreading out here and there into lakes : under such conditions we may readily ima¬ 
gine the country to have abounded with dense jungles of succulent plants suited for the 
support of large herbivores like the hippopotamus, rhinoceros, elephant, &c. ; the condition 
of the country was probably more like that of Assam at the present day, where the rhino¬ 
ceros, elephant and bufl'aloe still exist. Evidence of the former existence of extensive 
forests in these regions is afforded by the vast number of tree-stems found in the Nahan 
sandstone of Jogi-Tilla near Jhilam, and more sparingly in other places. 
