104 



NEW YORK STATE MUSEUM 



Gallupville. 5 miles east of Schoharie, showing that the extreme 

 eastern extension of the great Salina beds of New York can not 

 be far from the town of Knox, Albany co., at which place it is 

 quite likely that the Cobleskill slightly oyeiiaps the Salina. Both 

 of these formations are absent at Altamont, a few miles farther 

 east, and the Rondout is seen resting directly on the Lorraine 

 beds." 1 



The age of the shales here considered has been variously judged. 

 The name pyritous or pyritiferous shales was applied to this 

 formation by the elarly geologists, and since it occurred below 

 the Coralline or Cobleskill limestone, which was regarded as of 

 Niagara age, and above the Shawangunk grit, which was supposed 

 to be the equivalent of the Oneida conglomerate of central New 

 York, its age was assumed to be Clinton. Recent investigations, 

 by Ulrich and Schuchert, and by Hartnagel, have shown that the 

 formation in question is of late Siluric age, the former authors 

 regarding it as a part of the Cobleskill and including it within the 

 Manlius scries, while Hartnagel, Clarke and others regard it of 

 Salina age. As will be shown presently, it is probably the partial 

 equivalent of the lower cement bed of Rosendale which in turn 

 represents a part, but probably not the whole, of the Bertie water- 

 lime series of western New York. 



The Cobleskill limestone 



Resting immediately on the Braynian shales in the Schoharie 

 valley we find a heavy bedded, semicrystalline, fossiliferous lime- 

 stone, in places largely com/posed of fragments of shells, crinoids 

 and corals and with the texture of a sandroek, while other por- 

 tions are more muddy, consisting largely of impalpable water- 

 limes. The formal ion has been most thoroughly studied by Mr 

 C. A. Hartnagel to whose important paper the reader is referred 

 for details. 2 This bed has long been known as the "Coralline 



^Loc. cit. p. 114-15. 



Preliminary Observations on the Cobleskill ("Coralline") Limestone 

 of New York, by C. A. Hartnagel. N. Y. State Paleontol. An. Rep't. for 

 1D02;N. Y. State Mus. Bui. 69, p. 1109-75. 



