NEW YORK STATE MUSEUM 



Fig. i Generalized columnar section of the rocks of the Brier Hill, Ogdensburg 

 and Red Mills quadrangles 



Character of the Precambrian surface under the Paleozoics. 

 It has been shown in many of the recent New York reports that 

 Paleozoic deposition commenced upon a Precambrian surface 

 which was characterized by considerable irregularity. This irregu- 

 larity seems to have been most pronounced on the northeastern 

 margin of the Adirondacks, in Clinton county, and to diminish in 

 amount both to the south and to the west. On the southwest, in 



