A DEVONIAN OUTLIER OF THE OZARK UPLIFT 455 



pseudomorphous after pyrite. The quartzite is somewhat frac- 

 tured, and these fractures are filled with a soft, yellow, non- 

 fossiliferous, somewhat conglomeratic sandstone. 



From the structure and secondary growth it seems evident that 

 the rock was originally a calcareous sandstone, laid down by an 

 advancing sea against an old land mass. The calcareous matter 

 has been completely leached out, and much of it replaced by silica. 

 The soft, yellow sandstone is of later age, either basal Mississippian 

 or Pennsylvanian. 



PALEONTOLOGY 



Fossils are abundant in the quartzite. They are not evenly 

 distributed, but are most abundant at the base. At first glance, 

 parts of the stratum appear to be barren, but careful search of 

 almost any fragment will reveal fossils. The fossils all occur as 

 external and internal molds, and in most cases the preservation 

 is excellent. Corals and MoUusca dominate the fauna. Other 

 forms are not common, though individuals of a given species may 

 be very abundant. 



The following table gives a list of the species which have been 

 obained from this quartzite, and also their occurrence at other 

 locaHties. Column i shows species occurring in the Grand Tower 

 formation in southern Illinois; column 2, species occurring in the 

 Jeffersonville beds at Louisville,. Kentucky; column 3, species 

 occurring in Michigan; column 4, species occurring in Ohio; 

 and column 5, species occurring in New York.^ 



' Faunal lists : 



1. Illinois: S. Weller, "Correlation of the Devonian Faunas in Southern Illinois," 

 Jour. Geol., Vol. V (1897), pp. 625-35. 



T. E. Savage, "The Grand Tower (Onondaga) Formation of Illinois and Its 

 Relation to the Jeffersonville Beds of Indiana," Trans. III. Acad. Set., Vol. Ill (1910). 



2. Indiana, Kentucky: E. M. Kindle, "The Devonian Fossils and Stratigraphy 

 of Indiana," Ind. Dept. of Geol. a?td Nat. Res., Twenty-fifth Ann. Rept. (1900), pp. 529- 



758. ' . ^ 



H. Nettleroth, Kentucky Fossil Shells. Monograph, Kentucky Geological 



Survey, 1889. 



W. J. Davis, Kentucky Fossil Corals. Monograph, Kentucky Geological Survey, 

 1885. 



3. Michigan: C. Rominger, Geol. Stirv. Mich., Vol. Ill, 1876. 



4. Ohio: F. B. Meek, Pal. Ohio, Vol. I, 1873. 

 H. A. Nicholson, ibid., Vol. II, 1875. 



5. New York: James Hall, Paleontology of New York, Vol. IV, 1867, and Vol. V, 

 Part II, 1879. 



General: Grabau and Shimer, North American Index Fossils, 19 10. 



