The Mississippian (Osage) camerate crinoid Steganocrinus is divided into three species-groups on the basis of material from the Lake Valley Limestone, New Mexico, the Fern Glen Limestone, Missouri, and the Burlington Limestone, Missouri and Iowa. S. araneolus (Meek and Warthen) is a growth variant of S. pentagonus (Hall). Six new species are S. altus, S. longus, S. multistriatus, S. robustus, S. planus, and S. burlingtonensis. Synonymies of species previously assigned to the genus are included.