Traces of the Late Bathonian sea transgression have been discovered on Kote
l'nyi Island. The age of the transgression is evident from findings of two
ammonite species of the Cadoceras (Catacadoceras) group belonging to the Ca
doceras barnstoni Zone - C. (C.) barnstoni (Meek) and C. (C.) perrarum Voro
nez - in redeposited nodules. A detailed description of the species is prov
ided.