Published online by Cambridge University Press: 14 July 2015
Crinoids flourished during the Early Mississippian, with late Osagean crinoids being among the most diverse and well studied. Among others, late Osagean crinoid faunas include the well-known Crawfordsville and Indian Creek localities in Montgomery County, Indiana (Van Sant and Lane, 1964; Lane, 1973), and the Keokuk Limestone in the Mississippi River valley stratotype region. the late Osagean faunas in North America have been comprehensively revised recently in a series of studies (Ausich and Kammer, 1990, 1991a, 1991b, 1992; Ausich and Meyer, 1992; Kammer and Ausich, 1992, 1993, 1994, 1996; Ausich et al., 1997, 2000; Meyer and Ausich, 1997).