CARBONIFEROUS AGE. 165 



Now the thirty fossils in bed 3, and the sixty-six in bed B, of this 

 section are all of them in the Illinois, Indiana, and Missouri coal 

 fields characteristic of the Upper Carboniferous and not of the 

 Permian, though some of the genera are known to pass into it. 

 They cannot therefore be Permian, as Marco u and Geinitz supposed. 

 The beds, on the other hand, at Bellevue and Omaha which they re- 

 ferred to the Sub-carboniferous, contained the characteristic organic 

 forms that characterize the true Upper Carboniferous everywhere 

 else in this country. These distinguished foreign geologists at- 

 .tempted to generalize on American rocks by the principles that 

 interpret aright European geology, and hence they were led into a 

 blunder. Here, almost universally the vertical range of species is 

 much greater than in Europe. American geology must be studied 

 independently of European systems, or at least cannot be interpreted 

 by them. 



Coal. Thus far no thick workable beds of Coal have been found 

 in our carboniferous measures. The question rises whether there 

 is any probability of any valuable beds being found anywhere in 

 the State. Truth compels the admission that such a result is un- 

 certain and even doubtful. 



Mr. Broadhead, one of the State Geologists of Missouri, has long 

 since reached that conclusion with reference to the Upper Carbon- 

 iferous measures of that State, where, owing to changes of level and 

 numerous natural exposures a great thickness of these beds had 

 early and easily been examined by him. He gives sections through 

 these rocks extending to a depth of nearly two thousand feet before 

 reaching coal two and a half feet thick, all above being only from 

 a few inches to two feet in thickness. Dr. White's numerous sec- 

 tions observed in many places west of Winterset to the Missouri 

 show clearly that the upper series thicken westward and south- 

 westward, and not by the super-position of newer beds, but simply 

 by the thickening of those seen at that place. At a few places a 

 considerable thickness of these upper beds have also been examined 

 in Nebraska along the Missouri, and with the same result as in 

 Missouri and Iowa. Mr. Croxton, as early as 1865, made an arte- 

 sian boring near Nebraska City, to the depth of three hundred and 

 forty-four feet. Shales, limestones, micaceous sandstones and cal- 

 careous sandstones constituted the materials passed through, but no 

 indications of coal were met until at the depth of one hundred and 

 eighty-nine feet, a bed fifteen inches thick was struck. None was 



