GENERAL DESCRIPTION. 



291 



relation of the subdivisions to each other, and the manner in which 

 they lie on the Archaean. This will be better understood if the map 

 (Fig. 268) on page 297 be at the same time carefully examined. 





Area in the United States. — The area in the Eastern United States 

 in which the country rock belongs to this system is seen in the map 



