638 NORTH AMERICAN INDEX FOSSILS. 



" Greenbrier " limestone 1,500 ft. 



Pulaski red shale 20- 300 ft. 



{Section probably incomplete.) 



Lower Mississippic. 



Price sandstone 200- 300 ft. 



(Possible hiatus.) 



SUBFORMATION. 



Devonic — Kimberling shale. 



The value of the Greenbrier limestone of this section is probably 

 quite different from that of the limestone known by the same 

 name in southern Pennsylvania. 



In southern Virginia and in eastern Tennessee, the partly 

 Devonic Grainger shale (1,000-1,500 ft.) represents also the lower 

 Mississippic: the Nezvman limestone (1,000 ft.) represents approx- 

 imately the middle Mississippic and the Pennington shale (1,040- 

 1,100 ft.) approximately the upper. The last two are united by 

 Ulrich as his Tennesseean division, while the Mississippic part of 

 the Grainger is referred to the Waverlyan. Elsewhere in eastern 

 Tennessee^^ the base of the section is formed by the Chattanooga 

 black shale (often referred to the Devonic) which rests discon- 

 formably upon the Siluric or Ordovicic and is succeeded by the 

 Fort Payne Chert of Keokuk or even St. Louis age. Above this 

 rests the Bangor limestone in part, probably, representing the upper 

 Mississippic and disconformably succeeded by the Lookout sand- 

 stone of Pottsville age. In Alabama and northern Georgia^^ the 

 Floyd shale replaces the lower part, if not the whole, of the Bangor 

 limestone, the two, when occurring together being often separated 

 by the Oxmoor sandstone and conglomerate, and perhaps a dis- 

 conformity. In Nova Scotia the H or ton beds and the River dale 

 and Unio'n formations are referred to the Mississippic. 



VI AND VII. The Carbonic and Permic Systems. 



These two systems are not fully differentiated in North America, 

 and so are best treated together. In the east, the deposits are 

 mostly of the continental type ; in the middle country alternating 



^^ Pikeville, Chattanooga, etc., folios. 

 ^^ Rome folio. 



