254 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



The two varieties, which are equally common, occur together. 

 The first is, however, more frequent than the other in the plains on 

 the eastern skirts ; and the latter in the mountains. 



The pebbles are firmly cemented together, and are frequently 

 covered with a thick calcareous enduit. 



The blue limestone-boulders are sometimes much weather-worn ; 

 numerous regularly-formed channels radiate from a slightly project- 

 ing centre, and give the boulders somewhat the appearance of the 

 radiating concretionary nodules found in the Magnesian Limestone 

 of Sunderland. This, however, only occurs on the surface of the 

 blue limestone-pebbles, and is not observed on that of any other of 

 the components of this gravel. 



Throughout the whole of this vast accumulation the various pebbles 

 are thrown together without the slightest appearance of order or 

 stratification. They are nearly, if not all, derived from the rocks 

 composing the mountains immediately adjacent ; namely, the blue 

 limestone from the ambiguous Lower Secondary series ; — the white 

 and cream-coloured limestone and the pebble-breccia, from the Num- 

 mulitic formation ; — the red sandstones and variegated cherts, with 

 probably the quartzose sandstone and white quartz, from the sands 

 and gravels of the Gypsum-series, which this gravel-conglomerate 

 immediately overlies. It is remarkable that the boulders derived 

 from the greatest distance are the most common, while a very small 

 per-centage is found of the nearer rocks. This, however, may be 

 accounted for by the soft and friable nature of all the latter, which 

 have been ground down and form the sandy matrix. 



No trace of fossils has been met with in the limestone-gravel, 

 excepting such few as occur in the pebbles themselves. 



IL Tertiary Rocks. 



1. Gypsiferous Series. 



In this series I include all the stratified deposits above the Num- 

 mulitic limestone, to be hereafter described. 



The series consists of the following beds in descending order of 

 stratification : — 



1 . Fine gravel, passing into 



2. Friable, red, calcareous sandstone. 



3. Variegated marls, frequently saliferous ; with vast deposits of 



gypsum and thin beds of impure limestone. 



I have traced this formation in a N.W. direction, from Kazeriin to 

 Jezireh-ibn-Omar (lat. 29° 47' to 3G° 00' N.), nearly 700 geogra- 

 phical miles. How much further it extends in either direction I am 

 unable to say with certainty, though there is every reason to believe 

 that towards the south-east it passes through Behichistan, and is a 

 prolongation of a similar formation described by Captain Vicary as 

 occurring in Scinde. 



Beyond Jezireh-ibn-Omar, it follows the line of the Taurus, bearing 



