THE NORMANSKILL GRAPTOLITE FAUNA 281 



by Professor Smith reads as if the strata were very much faulted, 

 folded, or otherwise disturbed. The graptolite beds are seen to be 

 alternating with beds of chert and sandstone, and they are stated 

 to occur at the top of the series, not far below chert beds with 

 sub-Carboniferous fossils. The latter indicates either profound 

 thrust faulting or an interval of non-deposition. 



While the evidence gathered by those who, in the North, have 

 been wrestling with the problem of the age and stratigraphic posi- 

 tion of the Normanskill graptolite fauna points to nothing more 

 definite than probably lower Trenton, and no further extension 

 south than the present site of New Jersey in the Appalachian 

 geosyncline, it is believed that the facts here presented definitely 

 fix both age and position, and at the same time show a southern 

 extension as far as Tennessee. 



SUMMARY 



The great number of graptolites occurring in the Athens shale 

 of Virginia, and the fact that nearly all of those thus far identified 

 are Normanskill forms, leaves no doubt as to the identity of this 

 fauna with that of the Normanskill. The Athens shale carrying 

 this fauna is to be correlated with the Normanskill shale of New 

 York. 



The stratigraphic position of the Athens shale in southwestern 

 Virginia is clearly below the Trenton and above the Black River, 

 and it seems probable that when discovered at points intermediate 

 it will be found to occupy the same position. 



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