264 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Mar. 11, 



nearly horizontal ; and at the upper margin of the fault there are 

 t^ome of the strata hanging at various angles. This fault extends 

 east and west of the pass for many miles*. 



From this pass, proceeding north, the stratification is nearly hori- 

 zontal as far as Coombe, a place about 2100 feet above the sea. 

 From Coombe, in a northerly direction, the limestone gradually ob- 

 tains a dip to the north, amounting at its base to about 20°, and then 

 becomes lost beneath low sandstone hills. I was unable on the line 

 of march to give these interesting sandstone hills the examination 

 they merited ; they are composed of various-coloured sandstones, 

 with the strata dipping in a northerly direction at about 10° or often 

 less, thus corresponding so far in dip with the limestone ; but the 

 point of connexion between the latter rock and the sandstone escaped 

 my observation : this is to be regretted, as the subject is one of 

 importance. These hills are interesting from the vast quantity of 

 fossil bones and fossil wood which has been entombed within them ; 

 both are scattered about in vast profusion, and many cart-loads of 

 the bones could be collected from off an acre of ground. 



The wood bears the appearance of having been drifted and water- 

 worn previous to fossilization. I noticed palms and dicotyledonous 

 trees, one of which had a structure resembling pine ; some of the 

 broken stems had a diameter of two feet, and the quantity exposed 

 upon a small area was truly wonderful. I could only collect as 

 many of the bones as 1 could carry on my own person, but amongst 

 these are bones of the mastodon or elephant, portions of the tusk of 

 the same (no molars were observed), part of the jaw of hippopota- 

 mus, various bones of crocodiles with broken jaws of the same, and 

 many others which it will take time to make out. Thus it would 

 appear that on the northern and southern base of this limestone 

 range (the first proceeding northwards from the Desert), there are 

 strata having the same character, and that in both places similar 

 fossil bones are found imbedded in a loosely cemented gravel, con- 

 taining shells of Paludina and Cardium. 



About five miles to the north, advancing towards the Deyrah 

 Valley, a deep-bedded boulder conglomerate is met with; and one 

 mile further the nummulitic limestone again crops out, the strata 

 dipping north at about 45°. This range of limestone forms the 

 southern side of the Deyrah Valley, and, it will be observed, dips 

 into it; at the base it supports a stratum of conglomerate, which is 

 lost in the valley. 



The Deyrah Valley stretches nearly east and west, corresponding 

 with the mountain ranges ; its mean breadth is about four miles, 

 and its length perhaps forty miles. The soil is alluvial, and is in 

 many places covered with boulders of nummulitic limestone. 



The northern side of the valley is flanked with a range of hills 

 composed of stratified boulder conglomerate. The boulders are 

 nummulitic limestone, and the strata dip into the Deyrah Valley 



* The point of fracture exposed is highly glabrous, as if it had been exposed to 

 a grinding action. 



