HELDERBERGIAN OF THE UNITED STATES 



271 



of the United States. The writer recentl}' spent three days examining 

 these deposits and the fossils gathered by Mr Robert H. Gordon. No 

 complete section of the Helderbergian was seen in any one place, but 

 there was sufficient to show that this series is probably not less than 500 

 feet thick ; also that the four zones of the New York division are present 

 in the region of Cumberland, and that the Helderbergian apparently passes 

 without break into the Oriskany. In New York, the Helderbergian is gen- 

 erally followed by a few feet of Oriskany, which represent the later por- 

 tion and not the whole of this formation. The following is the Helder- 

 bergian and Oriskanian section about Cumberland, as made out by the 

 writer, while the fossils of the former series in Mr Gordon's collection 

 are listed beyond : 



Section at the "Devil's Back Bone," Kreighbaum Station, Baltimore and Ohio Railroad 



Marcellus shale. 



Oriskany. 



Kingston (or Oriskany). 



I 

 New Scotland and Becraft. -{ 



'Top not seen here, but elsewhere is a coarse sand- 

 stone. 

 Dark blue, arenaceous, heavy bedded limestone, 

 ' abounding above in Spirifer arenosus, Stroplieodonia 

 magnifica, and below in S. arrectus and Chonostro- 

 l phia complanata. Thickness about 150 feet. 



f Dark blue, arenaceous limestone with chert zones. 

 J Heavy beds above passing into thin beds. No 

 [ fossils were seen. Thickness about 125 feet. 



f Thin bedded, shaly limestone and shale with chert, 



abounding in New Scotland fossils. Shales with 

 Anoplotheca flabellites near the top. Thickness 

 about 75 feet. 



The fossils known from this zone are Zaplirentis, 

 Leptxna rhomboidalis, Stropheodonta beckii, Ortho- 

 thetes radiala ? Orthisperelegans, Spirifer perlamellosus, 

 S. cyclopterus, S. micropleura, Trematospira perforata, 

 T. near rnultistriata, Eatonia medialis, Rhynchonella 

 villicata? Phacops logani, Dalmanites micrurus, and 

 D. pleuroptyx. 



Railroad watch-house here. 



Coeymans limestone. 



Heavy bedded limestone with chert. Fossils abun- 

 dant, (iypidula galeata, etcetera. Thickness about 

 60 feet. 

 * Heavy and thin bedded bluish to yellowish limestone 

 with chert zones. A well developed Stromatopora 

 zone at the top and bottom ; also G. galeata, corals, 

 and crinoids. Thickness about 60 feet. 



