3G-i The Upper Devonian Deposits of Maryland 



blocky and contain, though rarely, a few fossils. About 600 feet above 

 the second turn there are fossils in rather blocky shales which are 

 brownish-gray in color, break into irregular pieces, and a little coarser 

 than most of those in this section. Specimens of Tropidoleptus carinatus 

 (Conrad) occur and a few other species. The lithologic characters of this 

 band are more like the Eomney than is generally the case in the Jennings 

 formation and the fauna is perhaps a recurrent one of that formation. 



No. 7. At the third turn on the road are gi-eenish shales alternating 

 with thin sandstones and near the base is a sandstone of greenish-gray 

 color 2 feet in thickness. Some of the thin, blocky sandstone layers 

 contain fossils and two specimens of Spirifcr disjunct us Sowerby were 

 found as well as others of Liorliynchiis mesacostale Hall, Ambocoelia 

 umhonata (Conrad), Cypricardella and layers composed of small crinoid 

 segments. 



This zone is very similar in appearance to many in the Chemung of 

 southwestern New York to which stage it is referred. The presence of 

 Spirifer disjunctus Sowerby a characteristic species of the Chemung 

 stage is regarded as proving the correctness of this con-elation. Some 

 of the thin sandstones are quite micaceous and split into rather smooth, 

 layers. A little higher in green argillaceous shales is a slightly irregular 

 layer in which are numerous specimens of Amhocoelia umhon-ata (Con- 

 rad). The exposed rocks from Town Creek up the lower part of Polish 

 Mountain are mainly greenish argillaceous and arenaceous shales alter- 

 nating with, thin sandstones of similar color. There is no sharp line 

 separating the rocks which are referred to the Woodmont and Parkhead 

 and those of the Chemung; but a gradual transition from the lower to 

 the upper members. Eocks containing Spirifer disjunctus Sowerby are 

 referred to the Chemung stage and the line of separation between the 

 Chemung and Parkhead is considered as below tliis zone. The average 

 dip of the rocks is 29°. 



No. 8. A little below the fifth turn on the road in somewhat blocky 

 shales, fossils are rare but a few small pelecypods were found. At 

 the sixth turn on the road are fine olive non-fossiliferous argillaceous 

 shales. 



