LOFTUS TURKO-PERSIAN FRONTIER. 255 



to the S.W., and is partially, represented on the Euphrates by the 

 gypsiferous marls, &c. described by Mr. Ainsworth as extending from 

 Balis, on the N., to Meshid Sandabiya, on the S. {Op. cit. p. 64-92.) 

 The actual breadth of this zone varies considerably, and, in conse- 

 quence of the beds passing imperceptibly under the alluvium to the 

 westward, it is very difficult, as I have previously remarked, to define 

 its limits in that direction (p. 249). 



Along the northern portion of the frontier detached patches of this 

 formation are frequently met with, — in some localities (as west of 

 Urumia) forming distinct ranges of considerable elevation. It may 

 probably be traced into the Caucasus. 



Considerable outliers of this formation extend in long lines of sand- 

 stone and gravel hills parallel to, and at a distance of twenty or thirty 

 miles from, the main chain. 



Striking off from it near Behbehan, in lat. 30° 14' N., the Zeitun 

 Hills rise into bold, rounded, and sometimes precipitous cliffs, through 

 which the Jerrahi River forces a passage into the plains of Dorak. 

 After continuing about fifty miles, the range sinks into the desert, and 

 is just distinguishable from the general level by a low, continuovis, 

 undulating line on the horizon, of thirty miles in extent. It again rises 

 into the Ahwaz range, and, crossing the River Kariin, constitutes the 

 celebrated ledge of rocks known as the Bund (Dam) of Ahwaz, of 

 which advantage has been taken for the construction of an artificial 

 dam, by which the water of the river was diverted in ancient times 

 from the original channel, for the purpose of irrigating the country 

 to the east. 



About midway between Ahwaz and Nahr Hashem, on the River 

 Kerkhah, the sandstone-hill called Jebel Mansiir (Prospect Hill) is 

 a very conspicuous point. 



On the west bank of the Kerkhah, the sandstone-range again 

 appears, running in the same general direction, a few miles north of 

 Hawiza, when it again sinks into low undulations which cross the 

 Diiwarij and Tib Rivers and joins the main chain west of Deh Luran. 

 About 100 miles still further northward, the outlier again strikes off 

 at Kiih-i-Manisht, passes to the east of Mendalli, and rises into the 

 high range known as the Hamrine, or Red Hills (from the colour 

 of the sandstone). See figs. 1 & 2. These cross the Diyala River 

 (called Shirwan during its course through the mountains) between 

 the villages of Khanikin and Shehreban, — form the Bund across the 

 Athem River, — cross the Tigris in lat. 35° 06', just below the junc- 

 tion of the Little Zab, — and are lost to my knowledge in the deserts 

 S. W. of the ruins of Al Hadhr. 



I have been somewhat diffuse in tracing the geographical extent 

 of these outlying ranges, because some doubts have been expressed 

 as to whether they are composed of rocks belonging to the same 

 geological age. 



From actual observation of all, except the Zeitun Hills (of which 

 however there can be no question), I can certify that they are com- 

 posed of the two upper divisions of the gypsum-series, namely, fine 

 gravel, and friable, red, calcareous sandstone ; and that the persistent 



