The suggestion by Sanford (1967, p. 994) that the Bedford Shale, Berea Sandstone, and Sunbury Shale of the Michigan basin are of Late Devonian age because these strata contain Hymenozonotriletes lepidophytus Kedo is invalid for these formations in the Appalachian basin, the area of their type localities. Endosporites lacunosus Winslow, a synonym of Hymenozonotriletes lepidophytus Kedo, occurs in upper Chautauqua (Upper Devonian) rocks through much of the Kinderhook (Lower Mississippian) strata in Ohio. The Sunbury Shale, the Sunbury Member of the Orangeville Shale in part of northern Ohio, contains a Siplionodella fauna which clearly demonstrates the Kinderhook age of the unit. The basal strata of the Bedford Shale contain Spathoffnathodus anteposlcornis which suggests a very Late Devonian or very Early Mississippian age for this part of the Bedford. Except for the basal fossil zone, most of the Bedford Shale and the younger Berea Sandstone overlie the Murrysville sand, which along the Allegheny Front in central Pennsylvania contains an Adiantites flora of Early Mississippian (Kinderhook) age. The presence of Adiantites in the Murrysville sand indicates that most of the Bedford Shale and all the Berea Sandstone are of Early Mississippian age. Lithostratigraphic evidence suggests that the Berea Sandstone of Ohio may be a temporal equivalent of the basal Beckville Member of the Pocono Formation of the Anthracite region of Pennsylvania.
The clearly demonstrable Kinderhook age of the Sunbury, Berea, and most of the Bedford in the Appalachian basin strongly indicates a similar age for the same units in the Michigan basin.
