Geological Papers, 251 



The portion of the tabulation containing the faunal character- 

 istics and general thicknesses is here omitted. 



In a tabulated section of the Kansas Permian rocks published 

 later* he did not differentiate the Marion formation, and let it, with 

 the Wellington shales of Cragin, go to make up the Sumner stage 

 of this author. I am in part at least responsible for this classifica- 

 'tion, and at the time doubted the advisability of subdividing the 

 Marion. Much additional study has convinced me of the advis- 

 ability of subdividing it, not to say the necessity of it. The Marion 

 will have to go back to its original rank of a stage. The further 

 discussion of the classification of the section into stages and larger 

 groupings must await the working out of the paleontology of the 

 beds. 



THE SECTION. 



In order to give an idea of the section as a whole and the rela- 

 tion of the Marion stage to that of the Chase, the formations of the 

 latter are enumerated from below upward: Wreford limestone, Mat- 

 field shales or formation, Florence flint, Fort Riley limestone, Doyle 

 shales, and Winfield limestone. The first, third and fifth of these 

 formations carry very large amounts of chert, which give rise to the 

 term "Flint Hills" for the rugged country of their outcrop. The 

 outcrop of the Marion rocks does not produce a rugged topography 

 and the flint is nearly absent. The faunal distinctions between the 

 two stages is quite as sharp as is the lithological or physiograph- 

 ical differences. 



TAe Luta limestone. — Over a very considerable portion of cen- 

 tral Kansas the Luta limestone forms the basal member of the 

 Marion stage. It is well exposed in the city of Marion on Main 

 •street, east of the bridge, by the church. The limestone at the 

 spring in the park is probably the Winfield. The Luta limestone 

 as a whole is a more or less cellular, soft, gray stone thirty feet in 

 thickness, with siliceous and other geodes scattered through it, and 

 layers of more or less abundant chert concretions. The type ex- 

 posure is taken at the crusher quarry about five miles northeast of 

 Marion, on the Chicago, Rock Island & Pacific railroad. Here the 

 total thickness is exposed, together with the top of the Winfield 

 limestone. This section is given below. From observations at 

 Arkansas City it seems that this limestone is very thin if it is not 

 wanting there, and it is absent from the section east of Newkirk, 

 Okla. It is exposed in a quarry along the railroad just north of 

 Herington, and seems to be but ten or fifteen feet thick. It is 



4. Prosser, Revised Classification of the Upper Paleozoic Rocks of Kansas, Jour. Geol.. X, p. 

 718, 1902. 



