54 Mr. Bain on Fossil Remains in South Africa. 



within a distance of 280 yards, measured at right angles to the strike, I counted 

 six anticlinal axes ; and found the strata at the summit of each axis bent at an 

 acute angle, like a ridge-tile, and the rock highly crystalline. 



The only data I have obtained, which may serve to indicate the age of this sand- 

 stone, are derived from a few vegetable casts and impressions, first discovered by 

 Dr. G. Atherstone, and which appear to belong to a Lepidodendron. The best speci- 

 men of these markings in my possession is too bulky for transmission to England. 



This rock is found on the coast at the mouth of the Great Fish river. Its 

 northern boundary passes eight miles to the north of Graham's Town, that is, 

 about thirty-five miles from the coast. To this formation belongs the rugged 

 mountain chain, the Zwarte Berg, which runs about seventy miles inland, in a line 

 parallel to the southern coast of the colony. I have also traced it further west- 

 ward to the mountains on the Hex river, near Worcester, about sixty miles north- 

 east of Cape Town. There it turns to the north-north-west, in the direction of the 

 country of the Namaquas. 



The next rock, in ascending order, is a claystone porphyry, consisting of a clear 

 blue base, with numerous imbedded pebbles of quartzite, claystone, &c. It occu- 

 pies the troughs in the undulating sandstone just described, which are bounded by 

 parallel mountain-ranges of the same rock. In the hollows of some of these 

 troughs it is from 300 to 500 feet thick, and, when seen in mass, has no appear- 

 ance of bedding. It thins off towards the sides of the troughs. It often appears 

 on the surface in small tongue-shaped portions, projecting from the ground at an 

 angle of from 70° to 80°, and looking like gravestones in a churchyard, 



I have traced one of the ridges of this rock through a distance of eighty miles, 

 from the point where the ridge emerges from the sea, at the mouth of the Gualana 

 river, to the point where the Great Fish and Little Fish rivers unite. The forma- 

 tion extends, I believe, much further both to the east and west. Its northern 

 boundary, like that of the quartzose sandstone, passes eight miles to the north of 

 Graham's Town. 



I shall now take my course from Graham's Town, along the military road 

 called the Queen's road, which runs northward to Fort Beaufort, forty-six miles. 

 At the eighth mile the clay porphyry is overlaid conformably by a formation of 

 great thickness, consisting of an argillaceous slate alternating with sandstone, and 

 containing thin laminae of hard, blue, impure limestone. Further northward, at 

 the Ecca heights, this slate contains a stratum nine inches thick, consisting entirely 

 of vegetable remains. At the Great Fish river the dip of the slate, which at the 

 eighth mile was 30°, is reduced to 5°. The same formation continues northward 

 about four miles further along the left bank of the river. Then a valley of eleva- 

 tion occurs, as if to allow the river a passage, and the slate is replaced by a green- 



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