GRAPTOLITES OF NEW YORK, PART 2 I I 



showed in 1901 that the belt of slate which contains this fauna in the Hud- 

 son river region underlies the Utica shale and correlated the zone with the 

 lower or middle Trenton. 



Since then still more direct evidence for the Trenton age of the Nor- 

 manskill Graptolite fauna has come to light. Weller [1903, p. 52] has found 

 the fauna in New Jersey near the base of the shale formation, from 50 to 

 75 feet above the Parastrophia hemiplicata zone which is near the base of 

 the Trenton limestone; and, since the sequence from the Trenton lime- 

 stone to the "Hudson River slates" at the locality is normal for New 

 Jersey, concluded that the graptolite beds "would seem to be equivalent to 

 about the middle portion of the typical Trenton limestone of New York, or 

 even to a position below the middle." 



Through the liberality of Prof. Eugene A. Smith, State Geologist of 

 Alabama, the writer has had the privilege of studying a well preserved, 

 slightly modified Normanskill fauna occurring in calcareous shale in Bibb 

 county, Alabama, which is associated with Trenton limestone and according 

 to Professor Smith of upper Trenton age. The following section of this 

 interesting locality has been kindly furnished. 



Section at Pratt's Ferry, Bibb county, Alabama, in descending order : 



1 Black shales, weathering yellowish and forming light yellow soil. Thickness 



not given feet 



2 Bluff of bedded chert 10-1 5 



Talus or slope of 40 feet vertical hight 



3 Heavy bedded chert 1 5-20 



4 Sandstone 15 



5 Beds of chert with Subcarboniferous fossils 20 



6 Sandstones alternating with black slates, but mostly sandstone 60 



7 Strata not seen 20 



8 Calcareous shales with graptolites, bluish black but weathering gray or white 



breaking up into small shaly blocks 40 



9 Thin bed of chert. Thickness not given 



10 Gray calcareous shales like no. 8, graptolitic 100 



11 A thin bed of sparry limestone full of small fossils and also graptolites (?). 



Thickness not given 



