GEOLOGY AND PALEONTOLOGY OF THE SCHOHARIE VALLEY 175 



the lower portion being most probably the equivalent of the 

 Brownsport of Tennessee. No unconformity has been reported 

 between these two members, but it probably exists. 



In Indian Territory, in the region of the McAllister coal field, 

 limestones apparently of the age of the New Scotland are found 

 resting on a bed with a Niagaran fauna. No unconformity 

 is recorded between the two, but here, too, one probably exists. 

 Besides the New Scotland species which this region has in com- 

 mon with New York^ other species unknown in the northern 

 region occur. Some of these have also been found in the Linden 

 beds of Tennessee, with which these beds are closely related. 



Considering all the evidence adduced, it appears that the 

 southwestern region was not covered by the Helderberg sea till 

 late Helderbergian time, while perhaps the Becraft and Port 

 Ewen beds were deposited in the New York area. The southern 

 element of the fauna unknown in New York, suggests a probable 

 southward connection with the Atlantic ocean. North of the 

 area depicted, the western shore line may have extended north of 

 the Gaspe peninsula and across the North Atlantic along what 

 has been termed the Hercynian chain of elevation, which thus 

 connected the American seas with those of early Devonic time in 

 Europe. 



At the end of Helderbergian time there appears to have 

 occurred another elevation of unknown magnitude which brought 

 portions of the Helderberg series above water level, when they 

 became subjected to erosion. The succeeding early Oriskany sea 

 was therefore restricted to the eastern portion of the Helderberg 

 sea. When the westward transgression of the Oriskany sea 

 occurred the subsiding land surface was more or less irregular 

 and not everywhere made by the same formation. Thus while 

 in the east the lower Oriskany beds rest on the Port Ewen, 

 the upper member of the Helderbergian, in the Schoharie region 

 and the northern Helderbergs, higher Oriskany strata rest on 

 the Becraft. At Litchfield in Herkimer county they rest on 

 the Coeymans (?), in central New York on the Manlius, and 



