Carhonifenm^ 2'rilobites. 73 



(Irah-culorcd litliogrjipliic liniestoiu' ; below these beds ii dark- 

 bine fetid limestone cii)pears. In Hardin and Grayson Counties, 

 between Cecilia Junction and East View, the rocks of this series 

 consist of a mass of coarse gray limestone, fine grained limestone, 

 oolitic and arenaceous limestones and shales. Throughout its 

 entii-e extent in Kentucdvy the series has a cavernous character 

 and may be identified by its topography of sinkhole and semi- 

 circular valleys. 



CiiKSTER Series. — These rocks were first described by Dr. 

 Shumard in Marcy^s Ex]->1. Red Eiver, p. 156, without naming 

 the group ; afterwards by Dr. Hall (Trans. Alb. Inst., 185G, 

 Vol. 4), as the Kaskaskia limestone ; and by the Geological Sur- 

 vey of Illinois (Vol. 1, p. 77), as the Chester grou}). 



In Arkansas, in Washington County, the series consists of 

 beds of dark-gray and bluish limestone, surmounted by massive, 

 coarse and fine-graiiied quartzose sandstone. In Illinois it com- 

 })rises three or more beds of limestone, with intercalated beds of 

 sandy and argillaceous shales and sandstones, the whole attaining 

 a thickness, in Raiidolph County, of at least 600 feet. At its 

 typical locality, the rock forms the cliff Ijordering the American 

 Bottom from Kaskaskia to Chester, and thence southward, hav- 

 ing a continuous exposure of more than ten miles. The lower 

 j)orti()n is composed of a compact ai-enaceous limestone, with 

 shaly partings. Its cenlral and npper beds include a thick bed 

 of sandstone; towards the top there is a mass of green shale or 

 marl 60 feet thick, overlain by a heavy bed of limestone. In 

 Kentucky, this series appears on the Louisville, Paducah and S. 

 W. E. R., above the St. Louis beds. These rocks consist of 

 limestone, sandstone and shale, and constitute a bed of passage 

 from the massive limestones of the Lower Carboniferous to the 

 coal measures. 



The members of this series occur at intervals from East View, 

 Hardin Co., to Litchfield, Grayson Co., and beyond; and also 

 at points between Scottsburg, Caldwell Co., and Trade water 

 River. 



The Chester series contains Pliillijjsia Stevensoni and Grif- 

 fitli ides granulata. 



