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tion of 2 to 5 feet of shale, with an irregular thin bedded seam of Coal A 
and the Millstone Grit. Some of the layers contain a few fossils. The 
following comprise all that could be recognized: Orthis umbraculum, 
Archimides wortheni, Athyris subtilita, Pentremites obessus, P. pyriformis, 
Spirifer incrassatus, Productus carbonarius, P. cora, and an abundance of 
encrinite stems. It belongs to the upper member of the sub-carboniferous 
limestone, and is designated by Prof. A. H. Worthen in the Geological 
Report of Illinois as the Chester Group. 
“The greatest development of this limestone seen in Greene County, is 
on Beech Creek, a branch of Richland Creek, on section 12, township 7, 
range 4, where it forms a great mural precipice, capped with sandstone of 
the Millstone Grit series. The following section was obtained at this 
locality : 
“Brownish-gray sandstone, in thick beds which has the ap- 
pearance of being most excellent building stone............ 25 feet O in. 
Shale, which thickens up to many feet and in places contains 
(CHOSILSS, a eta aen ce heuear prc ORCI Des rata) atconsa aceon sercusheuate ale auras eee 1 in. 
Buff colored limestone in which I saw Pentremites obessus, 
P. pyriformis, and Archimides wortheni............ Styne 20 feet 
ayes GlOUSESMAlen Pact) ya COVERCOe ye ae) a eters) olololeral cle ele aleleisiene 25 feet 
Bluish limestone (in which I saw no fossils, with intercala- 
tions of sandstone, mostly covered by talus............... . 50 feet 
MIRO TERNS cy atcv ens sievel sConereraus elena <i AoE A A OO ORG c 120 feet 1 in. 
“At the junction of the sandstone and limestone at this locality, there 
gushes forth a mammoth spring of good cool water. . . . . . 
“The sub-carboniferous limestone makes its appearance at the base of 
the hills along this creek for a distance of several miles, and is overlaid 
by a few feet of shales and the massive sandstone at the base of the Mill- 
stone Grit. It also makes its appearance at the ore banks on Ore Branch 
of Richland Creek in section 28, township 7, range 4, and on the eastern 
border of the county line near the Virginia blast furnace along Richland 
Creek.” 
Professor Cox has probably mistaken the heavy sandstone above the 
middle limestone for the Millstone Grit (Mansfield sandstone), and has con- 
fused the limestones. 
