THE GEOLOGICAL SECTIONS 26? 



7. Red calcareous shales, highly fossiliferous, with some chert in 

 bands toward the summit. This bed is identical, faunally 

 and lithologically, with the typical shaly Fern Glen bed 

 number 3 in the last section described Thickness, 15 feet 



6. Hard, tough limestone of a yellowish or buff color, sometimes 

 a little greenish, exactly similar to bed number 1 of the 

 Fern Glen section Thickness, 4% to 6 feet 



5. Greenish sandstone with numerous waterworn black pebbles. 

 Some of the pebbles show the structure of fish teeth of the 

 genus Ptyctodus. This bed exhibits many of the character- 

 istics of the Phelps sandstone at the base of the Kinderhook 

 in southwestern and central Missouri, and while it may not 

 be strictly contemporaneous with that formation, it is per- 

 haps homotaxial with it Thickness, to 1 foot 



4. Fissile shale, brownish in color when fresh and damp, weather- 

 ing to light yellow, greenish, or gray. No fossils observed 

 except at about one foot below the top, where an abundance 

 of Graptolites occur. This bed remfsents a portion of the 

 Maquoketa shale of Upper Ordowlan age, and the line be- 

 tween it and the bed above is a flk- of unconformity. Thickness, 15 feel 



3. Yellowish shale with harder, grrny, apparently magnesian 



bands 2 to 3 inches in thickness. About one foot from the 

 bottom is a thin layer with irregular, phosphatic nodules 

 and numerous diminutive pelecypod shells of the typical 

 basal Maquoketa fauna Thickness, 10 feet 



2. Hard, more or less impure limestone, darker than that below, 

 with the typical Rhynchotrema capax fauna of the Rich- 

 mond beds. This bed lies unconformably on the subjacent 

 limestone Thickness, ± 2 feet 



1. Light colored, nearly white or flesh colored, highly crystalline 

 limestone, some beds highly fossiliferous — the Kimmswick 

 limestone of Trenton age Thickness, 40 feet 



In this section the total thickness of beds which can be referred to the 

 Fern Glen formation is probably about 30 feet, including the whole of 

 bed number 7 and the lower portion of bed number 8. The limestone 

 bed number 6 is apparently the same as bed number 1 in the Fern Glen 

 section, the lower, more calcareous red member of the Fern Glen forma- 

 tion at its typical locality not being developed in this Kimmswick section. 



In Monroe county, Illinois, nearly opposite the Kimmswick locality in 

 Missouri, the Fern Glen beds are well exposed in the bluffs at Salt Lick 

 point, opposite Valmeyer. At this locality a large quarry has been oper- 

 ated in the Kimmswick limestone in the lower portion of the bluff, the 

 beds under consideration being exposed near the summit. The section 

 at this locality is as follows : 



4. Red limestone, with red calcareous partings — the Fern Glen for- 



mation Thickness, 23 feet 



