A. Holmes — Classification of Igneous Rocks. 



121 



II. 

 SATUEATED EOCKS. 



Or Soda Ori 2 . 5 Eocks. Qr 3 7-5 Soda-potash Bocks. Or 62 . 5 Potash Or 87 . 5 Eocks. Or x 



1 The name ' Monzonite ' as a specific name stands in urgent need of 

 limitation and redefinition. It is given here according to the usage adopted by 

 Brogger, although it should certainly be limited to rocks with a soda-lime 

 felspar at least as calcic as andesine, if not labradorite. The very broad 

 American usage of the term is particularly unfortunate. 



