U.S. NATIONAL MUSEUM 



S 1 L U R I A N 



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GENERAL TIME SCALE 



Northern Arkansas 



EastMissouriand Illinois 



Centra) ' L 



DEVONIAN 



(HELDERBERGIAN) 



Becraft (NX) 



New Scotland (NY.) 



Coeymans (NY) 



Keyser (W.Va.) 



Bailey Is. 



Haragan 



z 



< 





 D 

 >- 



< 

 O 



Manlius (NY.) 



Tonoloway (Md) 



Wills Creek (Md) 



Bloomsburg (Pa..) 



Sa.lina- M-Kenzie 

 (NY.) (Md.) 



Z 

 < 

 PC 



< 



< 



z 



< 



z 



D 

 UJ 



Louisville (Ky.) 



Guelph (Canada) 



Bcb (Tenn.) 



Beech River (Tenn) 



Racine (Wis.) 



Waukesha (Wis) 



Waldron (Ind.) 



Laurel (Ind) 



Rochester (N.Y) 



Irondequoit (N.Y) 



Williamson (N.Y.) 



Wolcott (N.Y.) 



Sodus (N.Y.) 



Thoro!d(Arthraphycus ss) 



Brassfield (Ky) 



ORDOVICIAN 

 (CINClNNATlAtH) 



Noix (Mo.) 



Edgewood (Mo.) 



Whiteoak (Tenn. 



Girardeau (Mo) 



Elkhorn (Ind.) 



Whitewater (Ind.) 



Maquoketa (Iowa) 



Liberty (Ind.) 



Waynesville (Ohio) 



Fernvale QVestTenn.) 



Arnheim (Ohio) 

 Dubuque (Iowa) 

 Maysville 



Bainbridee Is 

 (East of 

 St. Louis) 



St.Clair Is.(L)pper) 



St Clair Is.(Middle) 



'V- 



Henry hoU: 



St.Clair la (Lower) Brassfield (Sexton Creek) 



Cason shale 



Fernvale shale 

 (Upper Polk Bayou) 



mm 



!^^3 D?s!^etiaS€il 



-n,j~*™Sss. member 

 T>wte ^""{shale'Maquoketa" 



Fernvale shale 



St.Clair 



Chimney H 



Sylvan 



Fernvale 



