Uranoceras
Introduction '''''Uranoceras''''' is a barrandeocerid genus from the Middle Silurian belonging to the family Uranoceratidae, characterized by  its loosely coiled, gyroconic shell of 1.5 to 2 subquadrate whorls.The shell of ''Uranoceras'' is typically smooth but may have growth lines that form a hyponomic sinus on the venter. The Siphuncle is large, displaced slightly ventral from the center. Septal necks are straight; connecting rings cylindrical,  thin, and strongly contracted where they meet the necks. ''Uranoceras'' has been found in Indiana, Illinois, and Wisconsin in the United States; Anticosti Island in Canada; and in both central and northern Europe.
See also * List of nautiloids
References * Sweet, Walter C. 1964.Nautiloidea-Barrandeocerida. Treatise on Invertebrate Paleontology, Part K. Geol Soc of America and Univ Kansas Press. * Sepkoski, J.J. Jr. 2002.A compendium of fossil marine animal genera. D.J. Jablonski & M.L. Foote (eds.). ''Bulletins of American Paleontology'' '''363''': 1–560.Sepkoski's Online Genus Database (CEPHALOPODA)