GEOLOGY AND PALEONTOLOGY OF THE SCHOHARIE VALLEY 227 



In Moheganter hill the red shales and sandstones of the One- 

 onta make their appearance between 1200 and 1300 feet above 

 the level of the Schoharie river. The most easily reached out- 

 crops of these beds are on the bare knoll which rises to a height 

 of about 2000 feet above sea level behind the house of Mr John 

 Vroman on the road leading up Moheganter hill from the school- 

 house of district no. 11, 3 miles southwest of Middleburg. 



Catskill series 



This formation succeeds to the Oneonta beds in the eastern 

 Helderbergs and the Catskill mountains. It represents the time 

 interval during which the marine Chemung strata were deposited 

 in western New York and elsewhere. Like the Oneonta, it is a 

 nonmarine or estuarine formation and consists chiefly of red 

 rock. Xo representatives are found in the region bordering 

 the lower Schoharie, but in the upper gorges of that 

 stream, and its tributaries, good exposures of these rocks are 

 found. Their general character is indicated in the section from 

 the Catskills to Middleburg. given in chapter 5. 



Sequence of events during Middle and Upper Devonic time 



As shown in the preceding chapter, the marine invasion of 

 Oriskany time reached Ontario towards the end of that period, 

 when the Decewville beds were deposited, embedding their com- 

 mingled Oriskanian and Onondagan types. The depositional 

 equivalent of these beds in the eastern region appears to be found 

 in the Esopus shales. 



The character of this formation is such as to indicate unfavor- 

 able conditions for the existence of the Decewville fauna in the 

 eastern region, and it was not till the end of this period that 

 this fauna could invade the eastern region and become that of the 

 Schoharie grit. A comparison of the two faunas, i. e. the Scho- 

 harie and the Decewville, brings out this probable relationship. 1 



The origin of the Onondaga fauna is a question of considerable 

 interest. Thai il was not derived from the I Ielderbergian DOr 



1 See dh. 7, p. 325. 



