406 REPORT—1905. 
FRIDAY, SEPTEMBER 1. 
The following Papers were read :— 
1. The Dolomite Formation of the Transvaal. By C. Barinc Horwoop. 
The dolomite forms a considerable area of undulating grass country in various 
parts of the Transvaal, and is important as being practically the only source of 
the permanent rivers of the country. It lies conformably between the Black Reef 
Series and the Pretoria Series, forming with them the Potchefstroom System. 
This, however, is bounded above and below by unconformities, so that, as fossils 
are wanting, its age is not known. 
The dolomite is probably a deep-sea deposit, which has subsequently been 
dolomitised in shallow water, and has lost in the process all traces of stratification 
and organic remains. The upper layers contain much chert. 
In the East Rand it is associated with uniform layers of syenite or tonalite, 
which may probably be connected in origin with the plutonic series of the Bushveld. 
Gold occurs at Malmani in quartz fissure-veins, and in narrow interbedded 
quartz sheets in the Lydenburg district, 
2. On the Discovery of Marine Fossiliferous Rocks of Tertiary Age in 
Natal and Zululand. By Wi11am Anperson, 7.4.8.2. 
»<) Tertiary rocks of marine origin have not previously been recorded from South 
Africa. The present occurrences are confined to the coast of Natal and Zululand. 
The nearest outcrops of marine tertiaries are on the west coast of Madagascar. In 
Zululand they rest upon rocks which are known to be of Upper Cretaceous age and 
form a series of considerable thickness. They consist of highly coloured sand, 
showing false bedding, marls,and shales. In the upper portion of the shales and 
marls marine mollusca with foraminifera are plentiful, but not particularly well 
preserved, although sufficiently so for identification. “The mollusca were identified 
by Mr. R. Etheridge as of probably Eocene age, while the foraminifera were 
stated by Mr. Hinde to be of Tertiary age. In the lowermost beds, exposed at 
low water, Jarge quantities of mammalian bones occur in the shales. In most 
cases the individual bones are isolated specimens, although large portions of the 
vertebral column and the complete pelvic girdle of a large mammal were found 
in one piece. Associated with these remains are numerous large water-worn 
fragments of fossil wood, fish, and crustacean remains. The evidence points to the 
estuarine origin of the lower mammalian shales. Among the more common genera 
which occur are the elephant, rhinoceros, hippopotamus, with many others which 
have still to be identified. 
The other locality in which rocks of probably Tertiary age occur is on the 
Bluff, near Durban. This headland consists of a coarse, calcareous grit, with 
marine fossils which, so far, have not proved sufficiently well preserved for 
identification. It is more than probable, however, that the sandstones of the 
Bluff will prove to be of Tertiary age. In a bore recently put down on the Bluff 
for coal, over 300 feet of this calcareous sandstone was passed through, followed 
by over 300 feet of undoubted Upper Cretaceous rocks, which rest unconformably 
on the Keca shales of the district. 
This discovery of mammalian remains in marine Tertiary beds appears to be of 
considerable importance to South African geology, especially when considered in 
connection with the discovery of the remarkable series of extinct animals which 
liave lately been obtained trom the deposits of the Fayim desert by the officers 
of the Geological Survey of Egypt. 
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