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side of the Sutlej, great beds of limestone rich in Silurian fossils.* Mr. Salter has recognized the following genera among Captain Strachey's fossils :—

Cheirtirus. Strophomena. Cyrtoceras. Ghoetetes.

Lichas. Orthis. Litnites. Crinoid Stems, &o.

Asaphus. Leptoena. Tentaculites.

Calymene. Lingula. Murchisonia.

Ilkenus. Orthoceras. Ptilodictya.

Mr. Salter, M. Barraude and M. de Verneuil, who saw some of the fossils collected by Colonel Strachey, agree that they indicate beds of Lower Silurian. Wc shall see that beds of Silurian also exists in the huge mountains to the north of Skardo and near the Mustak Pass in the Korakoram chain.

Bat let us first relate what Colonel R. Strachey found in the high ranges south of the Sutlej.

The Silurian above mentioned rests on beds of slate without fossils, and this slate rests on schists, mica-schists and other rocks of the metamorphic group. Then above the Silurian limestone, some beds of carboniferous must exist, though they were not found in situ bv the explorer; Prodiieti, Athyris Royssii and other well known fossils were found in loose boulders near the Niti Pass. I believe also that some of the shells placed by Colonel Strachey and Mr. Salter in other groups belong really to the carboniferous; such is the Chmetes placed by Colonel Strachey in the Mushelkalk, but transferred to the carboniferous by Mr. Salter; the Ptilodictya Fenea (Salter), the narrow variety, which I have found in carboniferous beds in Kashmir; (it was naturally placed with the Silurian fossils by Mr Salter, on account of the Ptilodictya having been found as yet only in Silurian beds in Europe and America) ; the Spirifer Stracheyii, (Salter) placed among the Triassic fossils by Mr. Salter, and which is common enough in the Weean bed of carboniferous limestone in Kashmir; and lastly the Spirifer Rajah (Spir. Kcilhavii,

* On the geology of part of the nimalaya and Tibet, by Capt. E. Strachey, Bengal Engineers, P. G. S. in Proceedings Geological Society for June 1851, also " Palaeontology of Niti i" the Northern Himalaya, being descriptions and figures of the Palavwoi and Secondary fossils collected by Colonel K. Strachey K. E." « Descriptions by T. W. Salter, F. G. S., A. L. S. and H. T. Blanford, A. B. S. M., F. G. S.—Calcutta 1866."

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"Von Bueh), which has boon removed from the Trias by Dr. Oldham, and declared to belong to beds anterior to that epoch.

There is therefore a strong probability that both the Zeeawan bed (Productus semireticulatus, Athyris Royssii &c.) and the Weean bed (Spir. i. Stracheyii, Spir. Keilhavii) exist in the ranges near the Niti Pass, but have been much denuded and broken in loose fragments along the section-followed by Colonel R. Strachey.

Then comes what Colonel Strachey supposed to be Muschelkalk, and which Mr. Salter refers to the Kenper and Hallstadt bed of the Upper Trias. I cannot refrain from expressing a suspicion that a few of the shells referred to these beds do not really belong to them, and that fossils of various ages have been mixed, either from collecting them, without due care being paid to the strata in which they were respectively found, or from careless packing. There is such a great likeness between the figures of some of the Triassic Ammonites of Mr. Salter and those of the carboniferous ceratites of M. DeKoninck,* (see Ammonites Blanfordii, Salter, nov. sp. and Ceratites Lgellianus, Dekon. nov. sp.) that one finds it difficult to decide between these two great authorities. The species of ammonites figured in the Palaeontology of Niti have nearly all the eerntite-like sutures usual in triassic ammonites in Europe, and therefore much resemble deKoninck's ceratites.

It may be advanced, on the other side, that M. DeKoninck's ceratites belong to triassic beds; but these ceratites are to be Been in the Rotta Rob associated to some of the fossils which I have given as characteristic of my Weean bed of the carboniferous in Kashmir and the Punjab ; and a portion at least of this Woean bed would have then to be made over to the Trias. Unfortunately for this view, the mixture of Weean and Zeeawan fossils in some layers of the Rottah Roh (described in para. 60 of this paper), does not allow us to make the Weean anything but carboniferous, unless we are prepared to regard the Prod[ scmi-reliculatus, the A. Royssii, the A. Sahlilita and other such essentially

• "Description of some fossils from India, discovered by Dr. A. Fleming, of Edinburgh." By Dr. L. de Koninck, V. II. C. S., Profussor of Chemistry and Geology in the University of Liege—Journal Geological Society of London, Vol. XIX. p. 1.

carboniferous fossils as occasional inhabitants of the Trias!!! If

we are prepared to stretch the point so far, we may as well give

up at once all idea of successive faunas. I have, since writing the above, found in the Rottah Roh, some

beds containing a few fossils which appear Permian. I have not vet had time to examine the fossils with care; but should they prove Permian or Saliferian (St. Cassian),—and I have little doubt that they will be found to belong to either one or the other of these formations,—the presence of patches of such a bed on the top of the carboniferous would explain away, in a great measure, the difficulties I have now been considering.

I have said before that I believe the Saliferian of Upper India to belong to the Paikilitic formation, but that it has been found impossible as yet to demonstrate that such is the case. The discovery of one or two fossils may settle the question, if they were forms thoroughly well known as characteristic of the Indian Trias. The study of the fossiliferous Triassic beds in India is therefore of the greatest interest; but much care is required lest the mixture oi Paleozoic and secondary types should take place in our packing boxes and not in nature, and we thus become accustomed to regard, as characteristic of the Trias, shells which really belong either to the carboniferous, or to the Lias and Oolite.

To Colonel R. Strachey, however, is due the honor of having first discovered fossiliferous Triassic beds in the Himalaya; and we may hope that much light will be thrown on the Indian fossils of that age by Dr. Stoliezka, in his expected work on the Geology of Spiti.

Over the beds last described, Colonel Strachey found Jurassic beds; but the relation between the Triassic and Jurassic beds conld not be ascertained, owing to a great fault running parallel to the general N. W.—S. E. direction of the Himalayan ranges. The section exposed by this great fault is at least 5,000 or 6,000 foet in thickness, but the difficulties of the route prevented Colonel Strachey from examining it from top to bottom; the lowest beds were not examined. The lowest which were examined gave forms which Professor E. Forbes was inclined to identify with fossils which occur >n the fuller's earth and cornbrash of England. No Liassic forms ^ere discovered.

These inferior oolitic beds are capped by dark coloured shales containing belemnites and ammonites, and referred by Professor E. Forbes to the age of the Oxford clay. These shales are therefore the representatives of the several Jurassic beds we have already seen in several parts of the Himalaya and of the Punjab.

The oolitic beds are covered by grits, shales and limestone of unknown age, and finally by the great horizontal bed of what Colonel Strachey considers to be miocene (Siwalik) sandstones and conglomerates. I have said before that the identity of these sandstones, grits and conglomerates to the Siwalik formation is far from established, and that there are more reasons for considering them pleistocene, than for assuming them to be coeval with the deposition of the Sub-Himalayan tertiaries.

77. The Kilas Chain is of less elevation than the Ser and Mer, and its peaks are neither so numerous, nor so well known or so remarkable for their enormous mantles of snow. The principal summit is the Kailas (or Tise) peak, which rises to 22,000 feet above the sea, in longitude 81° 18', and is therefore far to the S. E. of our Western Himalaya. As it is, however, the ouly well known peak of the Chain, I have called the whole chain from its name.

The Kilas chain begins near Mount Haramash, N. of Astor and N. W. of Baltistan, and is traversed near Skardo by the Shigar river which cuts a passage across the range. The summit, Mashknlla, (16,919) towers over the alluvial plain of Skardo, Shigar and Kuardo. This mountain is mostly granite; its spurs show a great deal of metamorphic slate at a high angle of dip; and the little hill close to Skardo, evidently an off-shoot of the Mashkulla, is composed of an imperfect shist. All along the left bank of the Shigar river, schists of various sorts, especially mica-schists, and micaceous slates, together with metamorphic marbles, form the great wall of mountains that bound the Shigar valley to the N. E. Following the road which leads from Shigar to the Thale valley, by the Thale la (pass) Captain 6. Austen discovered some beds of limestone, resting on the micaslate, and I have coloured that bed of limestone Silurian in the Map. My reason for believing it to be Silurian is its proximity to limestone beds of similar appearance and position at the Mashabroom, and there, I believe, decidedly Silurian; and also the fact that the discoverer of the bed found thero a few fragments of fossils which he regarded as Palaseozoic, though different from any of the carboniferous forms which we found together in Kashmir. There is therefore presumption that this bed is Silurian, though of course it is merely a presumption. I have also assumed that a bed of limestone, seen to the South of Skardo, between that town and the Deosai (plain), is Silurian. We shall see the bed discovered at the Mashabroom, when we describe the Karakoram Chain.

From Skardo towards the S. E., the Kilas Chain appears to be nothing but a great granitic wall, along the foot of which runs the Imlns. Near Le in Ladak the range is crossed by the Digor La (pass), the road going through a succession of granitic rocks.

78. Between the Kilas and Karakoram Chains, we find the ragged district of northern Baltistan, the valleys of Saltoro, Nubra Shayokh and the Chinese province of Rodok. In the country of the Bait is, the Kilas and Korakoram Chains approach each other to within about 45 miles, as the crow flies, from range to range; whilst on the contrary the chains diverge as we proceed towards the S. E., the Korakoram chain having apparently a less southward direction that the other parallels of the Himalaya. In northern Baltistan, consequently, we find the country covered with mountains, cat with deep narrow valleys and mantled with immense glaciers ;* in Radok on the contrary high plateaux are abundant, and form to the north of the Pang Chong Tso (lake) and Pang Chong La (pass) considerable plains, 14,000 to 15,000 feet above the sea, arid and rainless, often not presenting a shrub for several marches; high deserts on which roam a thin population of nomade Turkomans who graze ehawl-wool goats on the scarce and far-between Aghil or grassy vales of these inhospitable regions.

There is no doubt that these high plateaux are similar in origin, age, and appearance to the great Thibet plateau through which runs the Sutlej, to the north of the Niti pass, and described by Colonel R. Strachey; and also to the Chang Tang and Rong plateaux of Ladak. All these high plateaux present a horizontal stratification;

• " On the Glaciers of the Mimtakh Eange," by Captain H. G. Austen, F. R G. S., &c., read before the Eoyal Geographical Society, London, on tuo 11th January, 1864.

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