184 Mr. Bain on the Geology of Southern Africa. 



belonging to the carboniferous system, but which opinion subsequent researches 

 have proved to be erroneous : otherwise I believe that description to be perfectly 

 correct, and to which I would now refer. The quartzose sandstone, which is the 

 general characteristic of this formation, passes into chloritic schist at De Stade's and 

 Van Staaden's Rivers, where rich mines of galena and copper-ore have been lately 

 successfully worked*. 



No workable coal has yet been discovered in this formation ; but I am told that 

 numerous species of carboniferous plantsf have lately been found near the Kowie 

 River in the talcose schist. 



The next rock in superposition is a claystone porphyry ; but the description of 

 this I shall defer for the present. Upon it rests a coarse 



Conglomerate, 



which has also been described in my former communication. It is here seen on 

 the flank of the Zuurberg, and portions of it appear in Section No. 3, at Grob- 

 belar's Kloof, near Graham's Town ; also at Lange Kloof, and other parts of the 

 district of George. 



Reposing conformably on this conglomerate is an exceedingly interesting group 

 of rocks, which I have ventured to call the 



Lias{?), 



from the prevalence of a characteristic liassic fossil, the Grypheea incurval. This 

 deposit does not seem to be anywhere extensively developed ; but, as a glance at 

 the map will show, occupies only small indentations of the coast about the estuaries 

 of our largest rivers. I know that more of these deposits than I have laid down 

 exist along the coast, especially in Kafirland ; but, not being sufficiently acquainted 

 with them, I have not given them a place in the map. 



I shall not attempt to describe the various fossil treasures of this highly in- 

 teresting formation ; suffice it to say, that whole forests of calcified trees, of large 

 size, are found in the neighbourhood of Sunday's and Bushman's Rivers, in a 

 most perfect state of preservation, imbedded horizontally in the rock. Ferns, 

 Zamias, and fragments of wood in a lignitic state, occur mixed up with fragments 

 of gypsum and Reptilian bones, together with marine exuviae — Trigonia, Ammonites, 



* Copper-ores are also found in Namaqualand in chloritic rocks ; but the mines cannot be worked to 

 advantage, on account of the scarcity of water and fuel. 



-f A specimen of micaceous schistose rock with Lepidodendron-lilie impressions, from Kowie River, is 

 in the Society's Museum. — Ed. 



X This fossil, although very similar to the species above referred to, is an Exogyra (E. imbricata' 

 Krauss). The formation in question, however, is probably referable to the lower Jurassic or lias series 

 on other fossil evidence : see Mr. D. Sharpe's paper in the sequel. — Ed. 



