This paper deals with research results of the inocerams from the Upper Cretaceous borehole sections of the Western-Siberian depression. The Lower and Upper Turonian inocerams – Inoceramus (Mytiloides) labiatus Schloth., I. (M.) hercynicus Petr., I. cuvieri Sow., I. lamarcki Woods (non Park.) var II Renng., I. cf. schulyinae Efrem. are described and figured. Questions of the Turonian stage stratigraphy and its dismemberment in France, Germany, USA, Canada and the former USSR are discussed.
