14 
Records of the Geological Survey of India. 
[vol. VIII. 
From a geological point of view the trip proved in many respects to be of considerable 
interest, particularly as supplementing some former observations made more to the west. 
Although there is not much variety in the rock formations we may distinguish three suc¬ 
cessive series. The most southern part of the province, along the foot of the hills, is formed 
of alluvial gravels and sand in whose unfathomable depths are swallowed both the Artush and 
Sujun rivers, before they can reach the Kashgar daria. Wherever irrigation from the latter 
is possible the fields appear to he fertile; but in the contrary case, the land is not much more 
than a mere desert covered with low and scanty scrubs of Ephedra Sp.? The marshy grounds 
along the river are the breeding places of innumerable waterfowl. Brahmini ducks and 
pintails were already selecting sites for their nests on the 1st of March. The latter must have 
only just arrived. 
Where high grass occurs wild pigs are not uncommon. 
The second series includes the low hills which extend diametrically from north to south 
over about thirty miles, while the prevalent strike is from north-east by east to south-west by 
west. All these lower hills are occupied by Artush beds, of which I spoke in a former com¬ 
munication. They are separated into two groups. The lower beds consist of greenish or 
reddish clays or sandstones, and the upper ones of coarse conglomerates, which on a hill south 
of Tangitar have a thickness of about a thousand feet. At their contact both groups 
generally alternate in several layers. An anticlinal runs almost through the middle of their 
superficial extent. At the fort Ayak-sugun it is caused by a low ridge of old doloinitic lime¬ 
stones on which the Artush clays and sandstones found a firm support. To the south of it 
the beds dip at angles of about 40° and 50° towards the Kashgar plain, in remarkably 
regular and successive layers. North of the ridge, which has no doubt a considerable sub¬ 
terranean extent in an east to west direction, all the beds dip towards north by west at a 
similar angle. Approaching the higher range more recent diluvial gravels cover most of the 
slopes. The geological puzzle of finding strata of young beds as a rule dipping towards a 
higher range composed of comparatively much older rocks seems to me to be due, at least in 
this special case, to the phenomenon that the atmospheric waters which, descending on the 
crest, flow down the slopes of the high ridge, gradually soften them, and if a subterranean 
outlet facilitate it the softened hods arc worn away. While this process is going on the more 
distant beds simply subside in order to fill the vacant spaces. In some cases a sinking or 
rising of the main range, or even an overturn of high and precipitous cliffs, seem to go hand 
in hand with the action of erosion, hut it is not always the case. I hope to illustiate this 
idea by a few diagrams, partly derived from actual observations on some future occasion. 
A third series of entirely different rocks forms the main range of hills which are a 
continuation of the Koktan range, and in which, more to the westward, are situated the 
Terek and Chakmak forts. The average height of the range is here between 1,200 and 1,300 
feet, single peaks rising to about 1,500 feet. The whole of the southern portion consists, as 
far as I could see, of carboniferous rocks, in which, however, there is a great variety of 
structure. The lowest beds are very often a peculiar breccia-limestone passing into regular 
limestone conglomerate. Above this are beds of solid grey dolomitic limestone, partly 
massive, partly stratified; the former possessing the character of reef limestone, and portions 
of it are indeed full of reef-building corals, crinoid stems, and a large Spirifer, the sections of 
which, when seen on the surface, have a striking resemblance to those of Megalodon. 
North of Tangitar.and about Bash-sujun I met in several places great numbers of fossils, 
but they were so firmly cemented in a calcareous matrix that only a few could be extracted. 
Among these I could recognise a small BeUeropkon, Produetus semireticulatus, and an 
Aihyris. A new Terebratula was also very common. Here about Bash-sujun and Tugur- 
