486 Annals of the South African Museum. 



of moisture resulting in torrential downpours and a consequent rush 

 of swollen streams at certain seasons. Even if that be a partial 

 explanation of the phenomenon, it is certain that the land to the 

 south must have had a marked elevation above that upon which the 

 sediments were deposited. No intensity of rain-fall would cause 

 pebbles and coarse sand to be washed from one area on to another 

 at approximately the same level ; in other words, subaerial conglo- 

 merates are not features of wellmatured or senescent stream-deposits. 



Transvaal Area. 



The correlation of the various outliers of the Busliveld Sandstone 

 with one another and with the Stormberg Series of the Cape has 

 been based mainly upon petrologiral grounds and upon the fact that 

 they underlie the amygdaloidal lavas. It has been supposed that 

 they are but remnants of a once extensive mass: but, however that may 

 be, it is certain that they were laid down upon an uneven surface. 



In the Springbok Flats area, north of Pretoria, the series is bent 

 into a double basin, and rests either directly on the Bed Granite or 

 upon highly inclined and sometimes much broken and faulted sedi- 

 ments of the Waterherg System. Tin- hasal beds of the Bushveld 

 Series here are frequently composed of debris and fragments of 

 granite, felspar, and quartz with interstitial partly decomposed 

 felspathic material - derived from the Granite - and occasionally 

 of large rounded quartzitc- prhhlrs, probably from the \\aterberg 

 Conglomerate. These coarse beds are confined to the edge of the 

 Series. Above them are in general, layers of rc-d marl or shale: 

 and they are followed by the true Bushveld sandstone. In the west 

 and south of the area, however, the red marl overlies the so-called 

 "Coal-Measure Grits". 



In the Komati Poort area the beds dip to the east, sometimes at 

 an angle of 10 degrees: and this dip has been held to account for 

 the occurrence of the series at a level so much below that of the 

 Springbok Flats. Here the ''Bushveld Sandstone" lies, apparently 

 conformably, upon the "Coal Measure Series' 1 - which lie themselves 

 upon the older Granites, schists, and altered sediments of the Swazi- 

 land System in the following order: Pale, hard, often coarse 

 felspathic grits, often massive with pebbly bands, at the base, fol- 

 lowed by sandy micaceous shales, carbonaceous shales, grits and 

 sandstones. Between these latter and the fine-grained sandstone 

 yellow shales occur at one or two points. The upper portion of the 

 Coal-Measure Series carries Glossopteris. 



Garrard has traced this series in a north-south belt through eastern 



