Examining the Molluscan Biostratigraphy of the Upper Cretaceous Judith River Formation, Montana

The Judith River beds were discovered by F.V. Hayden in 1855. F.B. Meek helped classified the specimens that Hayden had collected. In the documentations Meek and Hayden, the specimens were collected from the “Judith River Badlands.”\u27 There was no documentation on where in the Judith River Formation the specimens were collected by Hayden. Subsequently, Stanton and Hatcher (1905) collected specimens from the Judith River Formation and documented where in the formation the specimens were located. Correlating the distribution of the species identified by Stanton and Hatcher could lead to a hypothesis of where in the Judith River Formation Hayden had collected what became type specimens. Examining the published literature on the Judith River Formation was Phase 1 of this project. Phase 2 consisted mainly of field work in the Judith River Formation in north-central Montana. Phase 3 was the examination of fossil specimens brought back to the lab. A new species was discovered on the 2010 expedition. Tables were created based on available data from Stanton and Hatcher (1905) and Russell (1964). Meek (1876) and White (1883) drawings (compiled in Hartman 1987) and photographs of the new specimen were assembled into plates. This study indicates that Meek and Hayden\u27s fauna have a discrete biostratigraphic pattern within the Judith River Formation. There are key species that help establish the biostratigraphic framework