PRELIMINARY OBSERVATIONS ON THE COBLESKILL 

 ("CORALLINE") LIMESTONE OF NEW YORK 



BY C. A. HARTNAGEL 



More than 50 years ago Professor Hall 1 described a fauna 

 obtained from a thin mass of limestone outcropping near the base 

 of the Helderberg at Schoharie N. Y., which, on account of its 

 great abundance in corals, had become known as the Coralline 

 limestone. This is the lowest of the many limestone formations 

 in the vicinity of Schoharie. In its western extension it was 

 traced by its characteristic fossils as far as Herkimer county. 



From the paleontologic and stratigraphic evidence furnished 

 by the study of this limestone and also from a similarity in litho- 

 logic features, Hall concluded that the " Coralline " represented 

 the attenuated eastern extension of the entire Niagara group as 

 it then was known in western New York. The evidence for corre- 

 lation furnished by the 25 species of fossils specifically identified 

 from the " Coralline " was somewhat meager. With the excep- 

 tion of the corals, Spirifer crispus Hall was the only 

 species described as identical with the Niagara fauna, and even 

 that has been shown to be a variety. 2 Besides one or two species 

 of Stromatopora found in this rock and having but little value 

 in correlation, the abundant Favosites was identified as 

 F. n i a g a r e n s i s ( ?), while Halysites catenulatus 3 

 Linn., which at this time was not known above the Niagara, was 

 considered the most important of the fossil forms in the correla- 

 tion of the two rock masses. The many characteristic species 

 of the Niagara however were absent, while the " Coralline " was 

 characterized by a peculiar gastropod and cephalopod fauna, a 

 feature noticeably absent in the Niagara of western New York. 

 These discrepancies between the two faunas were observed by 



1 Palaeontology of New York. 1852. 2:321-38, pi. 72-78. 



2 Grabau. Geol. Soc. Am. Bui. 11 :352. 



8 This fossil was known above the Niagara only in the sense that Hall 

 regarded the overlying waterlime as Salina. Vanuxem had recorded this 

 species from the base of the waterlime group and had given the position of the 

 waterlime above the Onondaga salt group. This coral was identified by Van- 

 uxem asCatenipora labyrinthica. Geol N.Y. 3d Dist. 4th An. Rep't . 

 1840. p. 376. 



