482 NEW YORK STATE MUSEUM 



Feet 



chert. The beds are thinner than those of the over- 

 lying limestone. Apparently the equivalent of zones 

 B* and B^ on the north bank. 5=6 



A^ Massive light to dark gray crystalline limestone 

 varying in thickness from 11 feet, 6 inches to 12 feet. 

 It contains numerous crinoid segments and is in the 

 Trenton limestone. Represents the " marble " beds 

 or B^ of the north bank. 12=18 



A* Thin bedded, dark blue limestones containing 

 Trenton brachiopods. Under the highway bridge 

 and equivalent to zone B'^ of the north side. The 

 dip as measured on this bank varies from 4° to 5i°S 

 8o°W. Another dip of 2°S io°E was measured. 18=36 



On the south bank of the river below the paper mill are quar- 

 ries, the lower ones being worked for " marble " and the upper for 

 massive limestone. The section of the bank at this locality is as 

 follows : 



Feet 



54O Thick bedded, dark blue limestone. The 

 same zone as B^ on the north side and with the 

 same thickness. 3 if = 3 if 



O The "marble'' beds of the old quarries. 12^=16^ 



(7 Thin bedded limestone with Trenton fossils. 14=30 ^'^g- 



O Thicker bedded, more crystalline layers in 

 which are the upper quarries. 13 -^^^==44. 



C^ Thin bedded limestones to the top of the cliflF. 194=63^ 



Correction. In the paper on the Sections and thickness of the 

 Lower Silurian formations on West Canada creek and in the Mohawk 

 valley, published in the i^th annual report, a mistake was made in the 

 plates so that pi. 10 is stated to represent the " Falls in Flat creek, 

 Sprakers, over the Calciferous sandstone," when in reality it repre- 

 sents a view of the falls in the Oniskethau creek, Albany county, 

 over Esopus shales. 



