Maryland Geological Survey 



437 



Stevenson correlates his upper conglomerate with White's Lackawaxen 

 conglomerate. 



A section measured by the author in Thompson Township, Fulton 

 Count)^, Pennsylvania, renders it probable that Stevenson's upper con- 

 glomerate occupies approximately the position of White's Allegrippus 

 conglomerate, in Fulton County, while his lower conglomerate is probably 



Town Creek 



Allegany Co., Md. 



Swartz 



Huntingdon Co., Pa. 

 White. 



Thompson Twp. 



Fulton Co., Pa. 



Swartz 



Fulton Co., Pa. 

 Stevenson 



Fig. 2. — Diagram showing the correlation of Marine Upper Devonian of 

 Maryland and Pennsylvania. 



the upper conglomerate of the Parkhead sandstone member, illustrating 

 the difiSculty of correlating the strata over large areas by the use of the 

 conglomerates. 



The relation of the Maryland section to those of "White and Stevenson 

 is suggested tentatively in the preceding diagram, although fuller paleon- 

 tological data are needed before confident conclusions can be drawn. 



