THE GEOLOGICAL HISTORY OF THE COLONY 421 



of later rocks than to the resistance or structure of the 

 older beds. 



In addition to being crumpled up, the Malmesbury 

 and Kheis beds were invaded by granite. From Cape 

 Town northwards as far as the Moed Verloren hills in 

 Van Ehyn's Dorp granite and gneiss are in places found 

 in intrusive contact with the Malmesbury beds, and at 

 present there is nothing to suggest that we are concerned 

 with more than one period of intrusion. At Moed Ver- 

 loren, beds which can without difficulty be assigned to 

 the Malmesbury series are to be seen in contact with 

 the southern end of the great north-western granite 

 mass, which probably stretches through Namaqualand 

 and Kenhardt to Upington. Our information about 

 this great mass is at present rather scanty ; it has been 

 traversed in various directions by Wyley and Dunn, and 

 from their maps and descriptions we get no hint that it 

 belongs to more than one period of igneous activity. 

 Should a more complete survey prove that the mass is 

 one throughout, that conclusion will be of great impor- 

 tance, for at Upington the granite is intrusive in the 

 Kheis series. Thus both the Malmesbury and the Kheis 

 series may be older than the same body of granite. 



However that may be, it is certain that the Malmes- 

 bury beds and the granite were subject to prolonged 

 erosion before the Ibiquas, French Hoek, and the Cango 

 series were deposited in the west and south ; and in the 

 same way the Kheis series and the northern granite 

 contributed to the formation of the sediments of the 

 Ventersdorp system and the Black Beef and later 

 beds. 



