88 BuLi^ETiN 12 2l6 



PART IV. 



-t- 



Discussion and Correlation of Faunas. 



Bocarboniferous Faunas. 



Review of Previous Correlations. 



Very diverse conclusions have been reached as to the proper 

 correlation of these faunas in the Mississippi valley by paleontol- 

 ogists. The controversy relative to the age of the beds variously 

 referred to the Waverly, the Marshall group, the Kinderhook, 

 and the Chemung is one of long standing. The history of these 

 discussions has been well presented by Winchell* and more re- 

 cently by Williamsf. It seems unnecessary therefore to review 

 the history of opinion on this question except in so far as it relates 

 diredlly to the faunas in Indiana and Kentucky. 



In 1 84 1 Prof. James Hall made a brief examination of the beds 

 in Indiana between the Black shale and the Carboniferous lime- 

 stone. He identified the green shales of the Knobstone (New 

 Providence shale) with the Portage of New York. Of the fossils 

 in the sandstones above these shales he says: "I found shells 

 with close analogy, if not absolute identity, with Chemung spe- 

 cies. "| But the discovery of other shells of Carboniferous type 



*Proc. Am. Phil. Soc, vol. 11, pp. 57-83. 

 fBull. U. S. Geol. Surv., No. 80, pp. 173-192. 

 JTrans. Am. Assoc. Geol. and Nat., 1840-42, p. 280. 



