38 THE CANGO SERIES 



and others, usually thinner, have a fair proportion of 

 plagioclase in them. These diori tic -rocks seem to be 

 confined to the Malmesbury district. 



In the George granite there are some dykes of horn- 

 blende-schist, composed of long and rather fibrous 

 crystals of green hornblende, arranged parallel to one 

 another, with a smaller quantity of quartz and plagio- 

 clase grains between them, and a still smaller amount 

 of epidote. This rock is evidently a highly altered basic 

 dyke, but there is as yet little evidence of its original 

 nature. 



3. THE CANGO SERIES. 



In the Cango district, the country near the northern 

 boundary of Oudtshoorn on the southern flank of the 

 Zwartebergen, there is a group of sedimentary rocks 

 older than the Table Mountain sandstone, and therefore 

 usually classed with the Malmesbury beds. There are, 

 however, so many peculiarities in the Cango rocks 

 which separate them from the bulk of the Pre-Cape 

 rocks of the Malmesbury and other divisions in the 

 south-west of the Colony, that it is advisable to dis- 

 tinguish them by some other name ; the term Cango 

 conglomerate 1 has already been used for a prominent 

 band of rock in the series, and it will be convenient to 

 call the whole group the Cango series. 



The series forms a lenticular area about seventy miles 

 in length from east to west, from near Amalienstein 

 (Ladismith) to some few miles east of Meiring's Poort, 

 and at the most about nine miles wide- The Table 



1 G C., in., pp. 7, 68, etc. 



