abstract:An orthocone is a usually long straight shell of a nautiloid cephalopod. During the 18th and 19th centuries, all shells of this type were named Orthoceras, but it is now known that many groups of nautiloids developed or retained this type of shell.
Studyof the attitudes of the fossilorthocone nautiloids indicate that the paleocurrentswerefromnorth to south during the deposition of the Sandaokan Formation.