Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/155

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with basaltic greenstone. In this locality, but on the Itemani side of the Krantzkop, I found the small traces of organic remains in the shaly bed of the sandstone which I mentioned above.

Fig. 1. — Section through the Krantzkop Mountain.

                                    Valley of the        Zulu 

Itemani River. Krantzkop, 3800 feet. Tugela River. Country.

1. Granite. 2. Aphanitic diorite. 3. Mica- and talcose slates. 4. Table- Mountain Sandstone, with, 5, thin layers of a soft shale containing a few traces of fossils. 6. Melaphyre.

4. The Karoo Formation. — So called after the Karoos, the immense plains of the interior, as they are principally composed of strata of this formation, which has its greatest height above the sea in the Draakensberg range (see Section, Pl. II.). The lower part of the land on the Natal side of this range rests partly upon the Table- Mountain Sandstone, but not conformably. The Karoo sandstones and shales occupy the largest portion of South Africa, as they compose the whole of the interior, forming the high elevated plains of the Kalahari, the Free States and the Transvaal, as well as the countries to the north as far up as the Limpopo ; they are also to be met with at the Zambezi. As Mr. Tate, and Profs. T. R. Jones, Owen, and Huxley have already so ably described this formation with its fossil contents, little remains for me to say. The dark-grey and blue shales of Pietermaritzburg, containing oxide of iron in great quantities, represent the Ecca-beds of the great Karoo. Further up it passes gradually into sandstones of much the same lithological character as the Table-Mountain Sandstone, with intervening layers of shale, which at Ladysmith, Newcastle, in the Tugela valley, &c. contain beds of coal. Numerous remains of reptiles and plants are described, which come from the Natal side of the Draakensberg ; and therefore the age of these beds may be determined. Mr. Tate regards them as Triassic, whilst Mr. Wyley thinks that they belong to the Carboniferous period; but as the coal from Tulbagh,in the Cape Colony, is decidedly carboniferous ( Calamites, Equisetum, and Lepidodendron in the sandstone), and the succeeding Karoo formation (which is a freshwater deposit) does not lie conformably on the former, Mr. Tate's opinion seems the most acceptable. Also the same formation, with Dicynodon and Glossopteris Browniana, occurring in India at the base of the cretaceous series, is proved, by a careful examination of its flora, to be a Triassic deposit. There can certainly not be the slightest doubt that the Natal coal belongs to a far younger period