EXPLANATION OF PLATES 



595 



78. 

 77. 

 76. 

 75. 

 74. 

 73. 

 72. 

 71. 

 70. 

 69. 

 68. 

 67. 

 66. 

 65. 

 64. 

 63. 

 62. 

 61. 

 60. 

 59. 

 58. 

 57. 

 56. 

 55. 



54. 



Oo. 



52. 



51. 



50. 



49. 

 48. 

 47. 

 46. 

 45. 



44. 

 43. 



42. 

 41. 



40. 



Pittsburgh coal. 



Morantown coal. 



Upper Pittsburgh limestone. 



Lower Pittsburgh sandstone. 



Little Pittsburgh coal. 



Lower Pittsburgh limestone. 



Second Little Pittsburgh coal. 



Third Little Pittsburgh coal. 



Summerfield limestone. 



Connellsville red bed. 



Connellsville sandstone. 



Franklin rider coal. 



Franklin coal. 



Lonaconing sandstone. 



Upper bench of Lonaconing coal. 



Lower bench of Lonaconing coal. 



Hoffman sandstone. 



Upper Hoffman coal. 



Middle Hoffman coal. 



Hoffman limestone. 



Lower Hoffman coal. 



Clarysville sandstone. 



Little Clarksburg coal. 



Upper bench of Clarksburg lime- 

 stone in Maryland, Clarksburg 

 limestone elsewhere. 



Upper Clarksburg red bed in 

 Maryland, Clarksburg red bed 

 elsewhere. 



Upper Clarysville coal. 



Lower Clarysville coal, upper 

 bench. 



Lower Clarysville coal, lower 

 bench. 



Lower bench of Clarksburg lime- 

 stone. 



Lower Clarksburg red bed. 



Morgantown sandstone. 



Morgantown red bed. 



Wellersburg rider coal. 



Wellersburg coal in Maryland, 

 "Elklick coal" near Somerset, 

 Pennsylvania. 



Wellersburg limestone. 



Barton rider coal. 



Barton sandstone. 



Barton coal in Maryland, "Elk- 

 lick coal" in West Virginia. 



Barton limestone. 



39. 

 38, 

 37, 

 36, 

 35, 

 34. 

 33. 



31, 

 30. 



29. 

 28. 

 27. 

 26. 

 25. 

 24. 

 23. 



West Millford coal. 



Upper Grafton sandstone. 



Birmingham red bed. 



Federal Hill coal. 



Duquesne coal. 



Lower Grafton sandstone. 



Skelley limestone in Ohio, Upper 



Ames eastward. 

 Harlem rider coal. 

 Ames red bed. 

 Ames limestone and fauna. 

 Harlem coal. 

 Ewing limestone. 

 Pittsburgh red bed. 

 Woods Run limestone and fauna. 

 Saltsburg sandstone. 

 Portersville limetsone and fauna. 

 Upper Bakerstown coal (May- 



nadier coal in Maryland), An- 

 derson coal in Ohio. 

 Albright limestone. 

 Cambridge red bed. 

 Cambridge limestone and fauna. 



Friend sville shale and fauna in 



Maryland. 

 Thomas sandstone. 

 Lower Bakerstown coal — Thoma.'^ 



coal in Maryland, Wilgus coal 



in Ohio. 

 Thomas limestone. 

 Meyersdale red bed. 

 Buffalo sandstone. 

 Brush Creek rider coal. 

 Brush Creek red bed. 

 Brush Creek limestone and fauna. 

 Brush Creek coal. 

 Irondale limestone. 

 Corinth sandstone in Maryland. 

 Gallitzin coal — Mahoning coal m 



Ohio. 

 Thornton clay. 

 Mahoning red bed, 



lower benches. 

 Mahoning limestone. 

 Piedmont coal. 

 Mahoning sandstone. 

 Upper Freeport rider 

 Upper Freeport coal. 



upper and 



coal. 



Note. — The correlation of the upper members is tentative. Their lenticulai- 

 and variable character forbids confident correlation by data now available. 



