632 STUART WELLER 



characteristic fauna, extends from near Hannibal, Missouri, nearly 

 60 miles to Hamburg, Illinois, where there are about four feet of 

 strata referable to this formation, carrying the typical fauna as seen 

 at Louisiana. The entire distribution, therefore, of both the arena- 

 ceous and calcareous facies of this Kinderhook fauna extends along 

 a comparatively straight line for 200 or 250 miles. 



The distribution of the beds carrying the fauna, which at Burling- 

 ton and Louisiana is confined to the higher beds of the Kinderhook 

 section, is quite different from the distribution of the beds just dis- 

 cussed. This fauna has its most characteristic expression in the 

 Chouteau Limestone of central Missouri, especially in Pettis and 

 Cooper Counties. At Pin Hook Bridge over Muddy Creek, 10 miles 

 northeast of Sedalia in Pettis County, there are 60 feet or more of 

 Chouteau Limestone, usually of a bluish-gray color, sometimes yellow- 

 ish, and sometimes arenaceous or cherty. This limestone rests with 

 apparent conformity upon limestones which are of Devonian age, as 

 indicated by the fossils. Lying above the Chouteau Limestone is 

 the Burlington Limestone, whose lower beds in this county contain 

 a fauna identical with the lower beds of the same formation at Bur- 

 lington, Iowa. At Sweney, 15 miles north of Sedalia on the Missouri, 

 Kansas & Texas Railroad, a large quarry has been opened in the 

 Chouteau Limestone, exposing about 60 feet, with probably the same 

 Devonian limestone beneath it, and the Lower Burlington Limestone 

 above it, as at the Pin Hook section. At neither of these sections have 

 the details of the distribution of faunules been studied out, but the 

 fauna as a whole bears the same expression as the fauna of the upper- 

 most beds at Burlington and Louisiana, although at Burlington the 

 beds bearing this fauna do not exceed 1 1 feet in thickness, more than 

 half of which is a yellow sandstone, 1 and at Louisiana the fauna, 

 so far as observed, is restricted to Keyes bed No. 8, 12 feet of brown 

 sandv shale. 2 Furthermore, at no locality in central or southern 

 Missouri has any trace of the Chonopectus fauna of the Burlington 

 section been observed, nor of the fauna of the Louisiana Limestone. 



In southwestern Missouri the same Chouteau fauna occurs that 



1 Bed No. 7, the soft, buff, gritty limestone at Burlington, is not Here included, 

 as its fauna is much more closely related to that of the overlying Burlington Limestone. 



2 Missouri Geological Survey, Vol. IV, p. 47. 



