332 



UNIVERSITY OF VIRGINIA PUBLICATIONS 



Chemical analyses of igneous rocks from Nelson County, Virginia — Continued 



I, Piedmontose (sodio syenite) ; II, Roselandose (gabbro-nelsonite) ; III, Nelsonose 

 (ilmenite-nelsonite) ; JV, Virginose (rutile nelsonite). 



The norms as calculated from these analyses and arranged in the same 

 order are given in the subjoined table. 



Norms corresponding to analyses on page SSI 



The four rocks represented by the analyses and norms given in tabular 

 form above are new tjnpes, and they fall into unoccupied positions in the 

 quantitative system. Since they fall within the limits of the classificatory 

 scheme, and are the first representatives of the tyipes to be described, new 

 magmatic names are proposed for them. 



