1146 



NEW YORK STATE MUSEUM 



From Rondout southwestward through Wilbur, the Wilbur 

 limestone is exposed at a number of points and rests unconform- 

 ably on the Lower Siluric (= Normanskill ?) shales. Still far- 

 ther soutwestward along Rondout creek the Wilbur limestone is 

 seen resting on the Clinton quartzite, but directly west, as at 

 Whiteport and Binnewater, the Wilbur limestone is lacking, and 

 the cement bed rests directly on the Clinton quartzite. At High 

 Falls there is a fossiliferous bed between the cement and the 

 Clinton quartzite, and it is referred to the Wilbur limestone. 



At localities where the Wilbur limestone or the Salina water- 

 lime rests on the Clinton quartzite, there is no marked evidence 

 of any unconformity, though the hiatus between them must have 

 been considerable if this quartzite is to be considered as Clinton. 



Passing north from Rondout, the Wilbur limestone is exposed 

 in an old tramway which leads to the Becraft quarries. Darton 1 

 at this point gives the thickness of the Wilbur limestone as 5 

 inches. My examination of this section does not in all respects 

 agree with' Mr Barton's. In describing the section above referred 

 to, he says: 2 



The lower limestone members are exhibited lying on the Hud- 

 son river slates in the railroad cut and some old cement openings 

 near the turnpike. There is a 4 to 6 inch bed of impure, ferrugi- 

 nous limestone containing Niagara corals. On this there lie 7 

 feet of dark gray limestones, impure near the base and for 2 feet 

 toward the top. Two feet above their bottom is a fossiliferous 

 layer containing Atrypa reticularis, a very unusual 

 occurrence in this part of the formation. This limestone is over- 

 laid by a 10 foot bed of cement rock, of which the upper 4 feet 

 are of poor quality. Next above is a heavy mass of fine grained, 

 dark colored, brecciated limestone, filled with a great variety of 

 corals representing the Stroinatopora layer of the Tentaculite 

 (= Manlius) series. It has here the very remarkable thickness 

 of 10 feet with only a few thin beds of typical Tentaculite mem- 

 bers above. 



As the result of my examination of this section, I have con- 

 cluded that the limestone beds containing Atrypa reticu- 

 laris should be included with the Wilbur limestone, which 



1 N. Y. State Mus. 47th An. Rep't. 1894. p.501. 

 ■ N. Y. State Mus. 47th An. Rep't 1S94. p.511-12. 



