PROBABILITY OF METEORITES HAVING FALLEN 133 
in the depths in the mines of Kimberley. The main group of them 
occurs below the first member of the Transvaal Formation—the 
Black Reef Series—and was called by Molengraaff the Vaal River 
beds, but is now more generally known as the Ventersdorp beds. 
They consist of lavas of varying basicity ranging from melaphyres to 
felsites and rhyolites and are usually accompanied by enormous devel- 
opments of agglomerate ranging from coarse boulder beds to fine 
volcanic ash. 
Two areas of these amygdaloidal melaphyres occur in the Prieska 
district under discussion, while other and smaller areas are to be 
found in the neighborhood. ‘The largest of the masses is found to 
the north of the district on the farm Zeekoe Baard; it wraps round 
the end of the range of hills called the Ezel Rand composed of Matsap 
(Waterberg) sandstone and separates these rocks from the granite 
to the west and partially interposes between them and the Keis or 
Black Reef quartzites. There is a small mass also lying apparently 
intruded in the Waterberg sandstone. On the south side of the Ezel 
Rand there are some steeply inclined beds of limestone and quartzite 
which look as if they were the basal beds of the great limestone series 
turned up by force from the direction of the center of the igneous 
mass. ‘Toward the point of the Ezel Rand there are tracts of agglom- 
erate which probably belong to the melaphyre. The southern extrem- 
ity of the melaphyre is on the farm Geelbecks Dam where it tapers 
out; the greatest width of the mass is on the farm Blink Fontein 
where it is g miles across, and the extreme length is 30 miles. A large 
portion of the area mapped in as melaphyre is, however, covered 
densely with red sand, through which the rock only crops out occasion- 
ally; on Schalks Puts and on the eastern part of Blink Fontein there 
* are conspicuous ranges of kopjes formed of the rock. 
The melaphyre is in contact with the Keis (Black Reef) Series 
of the farms Ezel Klauw and Louis Draai on the north, and with the 
Matsap (Waterberg) beds of the Ezel Rand, which it surrounds on 
three sides. To the south it is bounded by the Campbell Rand 
(Dolomite) Series on the one side and the granite on the other. The 
field-relationships are not compatible with the supposition that the 
origin of the melaphyre was volcanic, unless a group of faults is 
brought in to explain the contact of the amygdaloid with such a large 
