CORRELATION OF CARBONIFEROUS ROCKS 347 



quite closely with my earlier one, for it was stated in that paper 

 that: " The writer is not confident whether the Nebraska City 

 beds should be referred to the upper part of the Missouri forma- 

 tion, 1 or to the Wabaunsee formation of the Missourian series. 

 However, the faunal and lithologic characters of the beds 

 near Nebraska City agree quite closely with those of the lower 

 half of the Wabaunsee formation as shown along the Kansas 

 River above Topeka, and so the writer refers them provisionally 

 to it." 2 



The distribution of the carboniferous rocks in southeastern 

 Nebraska has been given by Mr. N. H. Darton, on a "Prelimi- 

 nary Geologic Map of Nebraska," 3 where they are represented 

 under the legend of the "Cottonwood and Wabaunsee forma- 

 tions." On the same map, a part, at least, of the rocks mapped 

 in the Big Blue valley as "Permian limestone" may be corre- 

 lated with the Chase formation of Kansas. 



It will be remembered that Marcou referred the Nebraska 

 City beds to the Permian, and in this correlation he was sup- 

 ported by Geinitz, who described the fossils collected by Mar- 

 cou, and strongly opposed by Meek, who referred the rocks to 

 the Upper Coal Measures. This difference of opinion led to a 

 sharp controversy, the essential features of which were noted 

 in my former paper. 4 There is now no question but that Meek 

 was correct in referring these rocks to the Coal Measures, as 

 was noted in the writer's former paper, and is now stated by Mr. 

 Beede. 



It seems important, however, to again call attention to the 

 fact that Meek in correlating these rocks along the Missouri 

 River in southeastern Nebraska with the Upper Coal Measures 



1 At the time the above article was written I understood that Dr. Keyes intended 

 to retain the above name for that division of the Missourian series next older than the 

 Wabaunsee formation. It was not used, however, and now Professor Haworth's Shaw- 

 nee formation includes that part of the series. 



a JouR. Geol., Vol. V, p. 151. 



3 Nineteenth Ann. Rep. U. S. Geol. Surv., Pt. IV, PI. LXXXII. 



4 Of>. citi, pp. 12-16. 



