DEFINITION OF THE TERM "HUDSON 



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and the Upper Silurian or Niagara horizon. This idea is expressed in the 

 following tabulation : 



In tabulating the formations in this manner the local names are preserved 

 and, at the same time, the position in the geological series is indicated by 

 the term Hudson. Thus, in speaking of the Hudson rocks in western New 

 York, we say the Hudson terrane consists in Lorraine of the Utica shale, 

 the Lorraine shale, and the Lorraine sandstone ; and, on the Salmon river 

 of the Salmon River shale and sandstone, and the Pulaski shale. 



In reply, then, to the question, " What is the value of the term Hudson 

 River in the light of recent geologic research," I think we may say that its 

 essential part is established by the rules of geologic nomenclature, except 

 against the prior use of the name Salmon River. In relation to this, I think 

 all geologists will agree that the interests of geology will be subserved by 

 leaving the term Salmon River in the obscurity in which it has so long re- 

 mained. The term Hudson has a clear and distinct meaning. It is known 

 in the geologic nomenclature of America and Europe, and it is sustained by 

 the testimony of the rocks in the valley of the Hudson. 



