Walcottoceras
Walcottoceras is a genus of cephalopods from the Lower Ordovician included in the ellesmerocerid family Protocycloceratidae according to Rousseau Flower in 1964.
The shell of Walcottoceras is small, slender, compressed, with prominent annuli ; may be straight or slightly endogastric.
Could be said to be an annulate Ectenolites.
Walcottoceras has been found in the Lower Ordovician of British Columbia, Alberta, Utah, and New York.