﻿Notes on the Geology of South Africa. 503 



exception of some erosion after the deposition of the Eocene beds, 

 the greatest erosion, including the cutting-out of the Nile Valley, 

 took place in Miocene times, while a certain amount, bringing the 

 area to its present condition, was done in Quaternary times. This 

 agrees with the observations of the French geologists in Algeria. 

 The origin of the silicification of the fossil trees of the sandstone- 

 deposits is discussed, and the action of water containing sodium 

 carbonate suggested as a cause. 



2. ' Notes on the Geology of South Africa.' By D. Draper, Esq., 

 F.G.S. 



The district here considered includes Natal, Zululand, Swaziland, 

 the S.E. part of the Transvaal, and the Eastern part of the Orange 

 Free State and of Basutoland. Physically it comprehends : — 1. The 

 Drakensberg llange ; divided into — a, Mountain portion ; b, Hill- 

 covered plateau ; e, Highveld plateau : 2. The terrace along its foot : 

 3. The coast-belt. Their main features and characteristics are 

 described. The geological formations are : — 



( 1. Volcanic Beds. 



. TT 2. Cave Sandstone. 



| Lpper.^ g lledBeds . 



Karoo I ^ 4 Molteno Beds. 



Eeds - ' f 5. Beaufort Beds. 



Lower. \ 6. Ecca Beds. 



J. Dwyka (Ecca) Conglomerate. 



[Bokkeveld Beds, wanting.] 

 8. Gats Rand (Zuurberg) Quartzite. 

 Palaeozoic. <J 9. Dolomitic Limestone. 



j 10. Table-mountain Sandstone. 

 |^11. Malmesbury Schists. 

 12. Gneiss and Granite. 



No. 1. Briefly noticed. 2. This caps the hills of the plateau 

 (1, b) ; and has yielded fossil fishes (described by Mr. A. S. Wood- 

 ward, F.G.S.) in the Orange Free State. 3. These are exposed in 

 the 0. F. S., at Harrismith, about 100 feet thick, and containing a 

 bone-breccia from which reptilian remains were described by Prof. 

 Owen in 1854. Northwards the B,ed-beds change to a dark grit ; 

 and siliceous tree-stumps occur in the upper part. 4. These are 

 the well-known coal-bearing beds of the Highveld plateau (1, c) 

 and Natal, including the terrace (2) north of the Tugela River, and 

 Zululand. The lower 500 feet of these beds in Natal carry coal 

 better than that of the Highveld, but have been let down to a lower 

 level (about 2000 feet). In Natal they thicken northwards. On 

 the coast-line in Natal and Zululand portions are at a still lower 

 level and dip seaward at 20°. Anthracite occurs at St. Lucia Bay. 

 5. These form hill-side crags along the edge of the terrace (2) ; and 

 die aw 7 ay northwards near the Pongolo River. 6. The 'Pieterniaritz- 

 burg Shales' of Dr. Sutherland also die out northwards near that 

 river. 7. The 4 Glacial Conglomerate ' of Dr. Sutherland ; exposed 

 in high crags in the deeper gorges of the terrace (2) ; stratified and 



