Highest of all the Portage rocks are the Oneonta shales and 

 sandstones in the east, the Upper Portage sandstones of Caynga 

 section and to the west; 500 feet thick; fossils scarce. 



The Chemung Group. — The rocks of this group are so 

 named from Chemung Narrows, Chemung county. (See Frontis- 

 piece, PL I). They are at least 1,200 feet thick and consist of 

 gray shales and shaly sandstones often replete with large, well- 

 preserved fossils, especially brachiopods. (See PL IX-XIII). 

 In the western part of the state there are several "Rock cities" 

 or outcrops of coarse conglomerates belonging to this group: the 

 Salamanca, the Pope Hollow, the Panama and Charlotte con- 

 glomerates. These coarser layers when struck in oil wells in 

 northwestern Pennsylvania are termed oil sands, since they are 

 loose and porous and are veritable reservoirs of oil. 



In the Catskills the Chemung rocks consist of red and green 

 shales, sandstones and conglomerates, and form a part of what 

 was once known as the Catskill group. Fossils rare, mostly land 

 and fresh water species. See Fig. 124. 



The above statements may be expressed briefly as follows: 



Western N. Y. 



Chemung ( Shales, sand- 



group « stones and 



( conglomerates. 



f Upper Portage 

 I sandstones 

 Portage | Naples beds 



group \ Cashaqua and 

 Gardeau shales 

 and sandstones. 



Central N. Y. Eastern N. Y. 



Typical Che- 

 mung shales 

 and sandstones. 



Upper Portage 

 sandstones 

 Ithaca beds 

 Sherburne or 

 Lower Portage 

 shales and 

 sandstones. 



Catskill shales, 

 sandstones and 

 conglomerates. 



Oneonta shales 

 and sandstones 

 Ithaca beds 

 Sherburne 

 shales and 

 sandstones. 



Kinds of Life Represented by the Fossils of Southern 



New York. 



Though the Devonian may be called the Age of Fishes on 

 account of the considerable development of that class of animals 

 in certain localities at that time, it does not necessarily follow that 

 the young collector in this part of New York is going to fill at 



