Pinna peracuta Shumard.
Pinna subspatulata Worthen?
Bellerophon crassus Meek and Worthen.
Trachydomia wheeleri (Swallow) Keyes.
Pleurotomaria tabulata Hall.
Conularia crustula White? (Very large for this species.)
24. Calhoun Shales. This formation is fifty to sixty-five feet in thickness. The lower part is a layer of soft argillaceous sandstone from twelve to twenty feet thick. The upper portion of the formation is a bluish shale, arenaceous below, clayey above, and of comparatively fine texture. No fossils have been collected from this formation, except a few fragments of Calamites and Cordaites in a soft sandstone immediately beneath the Topeka limestone, in the eastern part of that city. The type exposure is at Calhoun’s Bluffs, three miles northeast of Topeka.
25. Hartford (Topeka) Limestone. (Adams’s MSS., by permission of U. S. Geological Survey.) The following section of the rocks is about as given by Doctor Bennett when he first described them:
| ft. | in. | ||
|---|---|---|---|
| g. | Limestone weathering buff | 2 | 0 |
| f. | Drab shales | 3 | 0 |
| e. | Limestone weathering buff | 1 | 6 |
| d. | Buff calcareous shales with abundant fossils | 2 | 0 |
| c. | Blue to brown limestone, always weathering to a brown buff, cherty near the top, fossiliferous | 5 | 8 |
| b. | Blue shales | 1 | 6 |
| a. | Blue limestone, weathering dark buff | 6 | 0 |
| Total thickness of formation | 21 | 8 | |
Most of the fossils enumerated below were taken from layers c and d, though the entire set is more or less fossiliferous, with about the same species running through them.