REPORT OF THE STATE PALEONTOLOGIST 1902 1199 



concretionary appearance consist of white quartz pebbles in 

 black chert cement. The cement matrix is rarely calcareous, 

 so that this rock resists erosion and decomposition better than 

 other members of the series. Throughout the bed are scattered, 

 sometimes abundantly, much waterworn fragments of Oriskany 

 shells. 



29-34 Sharp on the top of the black pebble bed lies a series of 

 siliceous and sandy limestones in thin layers of 4 to 12 inches 

 thickness, which when fresh are very hard and of black or dark 

 gray color, but which when weathered turn into a soft brown 

 rotten stone. These beds with a thickness of 42 feet in this 

 section, constitute the highly fossiliferous Oriskany which has 

 yielded such finely preserved silicified fossils, and of which the 

 upper layers are absent in this section. The entire thickness 

 of this upper portion of the formation approximates 50 feet, 

 in this immediate vicinity. 



North of Rondout the thickness of the Oriskany diminishes 

 to about 20 feet at Glenerie. Darton's figures of the thickness 

 of this formation [1894, p. 497] can not be depended on. In the 

 Rondout region, where Darton says it is " 30 feet, including the 

 conglomeratic member," we find it to be at least 60 feet, with 

 the upper portion removed by erosion. A carefully measured 

 section of the Oriskany, including the pebble bed at the base, but 

 without the top layers which here also have been removed by 

 erosion, along the railway at Whiteport station, shows 70 feet, 

 6 inches of this formation, while Darton [op. cit., p. 497] states 

 " In the Whiteport region and southward the formation con- 

 sists of a silicious limestone bed which has a thickness of from 

 8 to 9 feet." On the top of the hill 1 mile south of White- 

 port station, the total thickness of the Oriskany is about 80 

 feet. Ries. in his Report on the Geology of Orange County N. Y. 

 (X. Y. State Geol. 15th An. Rep't. 1897. 1:402), gives the Oris- 

 kany in the vicinity of the Xeversink valley north of Port Jervis 

 a thickness of 125 feet. This thickness increases to the south- 

 ward, as noted by Weller [1903, Geological Survey of New Jer- 

 sey, Report on Paleontology. 3:93] who quotes 170 feet for the 

 Oriskany in the Walpack ridge a few miles south of Port Jervis. 

 The Oriskany of New Jersey contains a fauna, that of the 



