PENNSYLVANIC-PERMIC PERIOD 571 



of West Virginia. This series begins with the Waynesburg coal, and 

 White has always regarded it as recording the time of the Permic. 



Case 207 has recently reviewed the vertebrate evidence on which Ameri- 

 cans have placed such dependence as proving the Permic age of the Wich- 

 ita red beds of Texas. Since Raymond found reptiles in the middle Cone- 

 maugh, which is even below the Monongahela, the uppermost series of the 

 Pennsylvania reliance can no longer be placed on the mere presence of 

 reptiles as positive proof for Permic age. This discovery led to Case's 

 review, and he concludes as follows : "The evidence from vertebrates is not 

 sufficient to demonstrate the Permian age of the beds in Illinois and 

 Texas ; they may reach down into the Carboniferous." 



It is now fairly well established that the Wichita and its fauna and 

 flora are not of true Permic time, but belong to the older Permic, the 

 so-called Permo-Carboniferous or Oklahomian, or the European Artinsk. 

 The Wichita flora correlates with the Dunkard, and the latter with the 

 European continental deposits, the Atunian and Cuseler, or the Eothlie- 

 gende. It is even possible that the Wichita is slightly older than the 

 latter, but in any event the ammonites correlate best with the Artinsk. 



Throughout the Mississippian sea the Oklahomian deposits are those of 

 a vanishing sea with abnormal marine conditions. Vast areas consist of 

 nothing but red beds, with here and there thin dolomite layers, and in 

 many places gypsum occurs in quantity, especially in Oklahoma, the 

 Jf G}^psum State." In Kansas the earliest Oklahomian deposits are still 

 those of normal marine waters, and this condition probably continues 

 longest in the Albany of Texas. 



Calif omian sea. — In California the equivalent of the Pennsylvanic has 

 at its base the Bragdon "shales, sandstones, and tuffs, with siliceous con- 

 glomerates (of Devonian pebbles) increasing in number and size from the 

 top toward the bottom." 208 The thickness is estimated at 2,900 feet, and 

 may attain to 6,000 feet. The fossils of this formation are very few, but 

 these link it directly with the overlying Baird. Among other forms were 

 found a Glyphioceras similar to sphcericus and Lithostrotion sublceve. 

 Diller refers this formation to the Mississippian. It may be that this 

 zone is older than the Pottsvillian, in which case it is of late Tennesseic 

 time. All depends on the age of the following Baird, which Diller 209 also 

 refers to the Mississippian, but which the writer regards as very early 

 Pennsylvanic — that is, Lower Pottsvillian. 



The Baird "reddish shales and sandstones with much volcanic mate- 



207 Case : Journal of Geology, 1908, p. 580. 



208 Diller : American Journal of Science, vol. 19, 1905, p. 383. 



209 Diller: Folio 138, U. S. Geological Survey, 1906. 



