52 aEOLOGICAL FORMATIONS 



have not been made out very satisfactorily. At every locality 

 where it has been reported in this region, its lithological char- 

 acters are very different from those in the more northern dis- 

 tricts, and its stratigraphic relations are for the most part 

 somewhat uncertain. However, Shumard reports it capping 

 hills of the Magnesian limestone series in Ozark, Douglas and 

 Wright counties, and overlaid by sandy shales containing typi- 

 cal Kinderhook fossils. Broadhead also believes it to be 

 recognizable in Oedar and Saint Clair counties ; while Swallow 

 states that 30 feet of it, preserving its characteristic texture, are 

 exposed in Jasper county. 



Although for many years past the Kinderhook beds have 

 been regarded as the basal part of the Lower Carboniferous 

 (or Mississippian ) series in the upper Mississippi valley, a de- 

 cided Devonian facies of the contained fossils has always 

 been observed. This peculiar faunal aspect has occasioned 

 much comment, and has attracted wide notice. So much were 

 some of the earlier geologists impressed with this character 

 of the organic remains, that they hesitated but little in refer- 

 ring the beds in question to the upper Devonian. 



The best exposures of Kinderhook rocks are found along 

 the Mississippi river at Burlington, Iowa, Kinderhook, Illinois, 

 Hannibal and Louisiana, Missouri. At all of these places the 

 lithological characters are practically the same, except perhaps 

 toward the more northern part of the exposed range, where 

 the upper part is changed somewhat, and the lower portion 

 does not rise above the water-level. At Louisiana the expos- 

 ures are perhaps more open to observation than elsewhere ; 

 though for 70 miles along the river the outcrop is practically 

 continuous. The vertical section has already been given in 

 another place. 



In 1852 * Owen, who was the first to give attention to 

 the geological details of the rocks as exposed along the " Fa- 

 ther of Waters " above the mouth of the Missouri, limited, as 

 already stated, the term " Subcarboniferous," which hitherto 

 had long been applied to all the strata below the Coal Meas- 



*U. S. Geol. Sar. WisconBin, Iowa and Minnesota, p. 92. 1852. 



