DOLERITES AND RHYOLITES OF NATAL AND ZULULAND. 149 



100-02 . 100-00 



100-74 . 100-15 



The analysis corresponds to the following- " norm" : — 



??AR> 



99-77 



and the rock in the American system would be classed as 

 Camptonose. Under 11, for comparison, is given the analysis 

 of a dolerite from Knob Head on the Ferrar Glacier, South 



