MEDLICOTT ALPS AND HIMALAYAS. 45 



this zone the rocks always exhibit more or less of disturbance, very 

 often to an extreme degree. 



There are two well-defined groups in this Subhimalayan zone. 

 Along their northern boundary the Upper Sivalik strata abut against 

 lower beds of the same Subhimalayan (Tertiary) series, of the 

 middle (or Nahun) group. These latter beds form a narrow band 

 of variable thickness, but rarely, if ever, absent, separating the true 

 Sivaliks (the strata which yielded the Fauna Sivalensis) from the 

 much older rocks of the higher mountains. Sir Proby Cautley has 

 identified the rocks of the Nahun band with the beds at the outer 

 base of the Sivalik hills, where they seem to be regularly overlain 

 by the younger Sivalik strata*. The collection of fossils from the 

 older beds, which might have thrown such light upon this strati- 

 graphical break, has been lost since its transmission to England ; 

 indeed I am told, by the distinguished donor, that this misfortune 

 has befallen it since the consignment of the collection to the vaults of 

 the British Museum t. Even without the palaeontological facts, the 

 relation I have described of the Sivalik and Nahun groups is re- 

 markably analogous to that of the Neogene and Oligocene groups of 

 the north-eastern Alps. 



In one portion of the north-west Himalaya we find a remnant of 

 a much older group of Tertiary rocks ; the bottom beds are the well- 

 known Nummulitic strata of Subathoo. They are overlain transi- 

 tionally by sandstones of the regular Molasse type, only thoroughly 

 indurated, like the Elysch sandstones of Appenzell. By position 

 this group identifies itself with the rocks of the outer edge of high 

 mountains, rather than with the true Subhimalaya, just as do the 

 corresponding rocks in the Alps, thus completing the analogy of the 

 sections with almost startling exactness. 



The Subathoo group rests high up on a base of the slates forming 

 the mountains, upon a denuded surface of which it had been 

 deposited, both rocks being now seen folded in the same contortions. 

 The younger groups of the Subhimalayan series (Sivaliks) only 

 appear at the outer base of the mountains, and the junction is as 

 apparently abnormal as anything seen in the Alps ; the dip of the 

 younger rocks is almost invariably towards the contact, the plane of 

 which underlies to the north, thus producing actual, though not 

 parallel, superposition of the older rocks. All the arguments as to 

 prodigious faulting &c. that have been applied to the Alps would be 

 just as applicable here. 



A very brief inspection of the Sivalik rocks made me averse from 

 the supposition of any great change in the features of the surface 

 since the time of their formation. There is at once apparent a most 



^- Journ. Asiat. Soc, Bengal, vol. iii. 1834, p. 528. 



t The more we see of these Sivalik rocks, the more does our admiration in- 

 crease for the discoverers of the Fauna Sivalensis. I failed to find fossils either 

 at Nahun or at the Kala walla pass ; and vdthin this last year Captain Godwin - 

 Austen, who has much experience as a collector, incited by my account of the 

 difficulty and of the interest attaching thereto, spent some time at Nahun 

 searching for fossils, but without the smallest success. 



